*
* Bash compat TODO:
* redirection of stdout+stderr: &> and >&
- * subst operator: ${var/[/]expr/expr}
* brace expansion: one/{two,three,four}
* reserved words: function select
* advanced test: [[ ]]
* $ "export" i=`echo 'aaa bbb'`; echo "$i"
* aaa
*
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
#include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */
#include <malloc.h> /* for malloc_trim */
# define PIPE_BUF 4096 /* amount of buffering in a pipe */
#endif
+//applet:IF_HUSH(APPLET(hush, _BB_DIR_BIN, _BB_SUID_DROP))
+//applet:IF_MSH(APPLET(msh, _BB_DIR_BIN, _BB_SUID_DROP))
+//applet:IF_FEATURE_SH_IS_HUSH(APPLET_ODDNAME(sh, hush, _BB_DIR_BIN, _BB_SUID_DROP, sh))
+//applet:IF_FEATURE_BASH_IS_HUSH(APPLET_ODDNAME(bash, hush, _BB_DIR_BIN, _BB_SUID_DROP, bash))
+
+//kbuild:lib-$(CONFIG_HUSH) += hush.o match.o shell_common.o
+//kbuild:lib-$(CONFIG_HUSH_RANDOM_SUPPORT) += random.o
+
+//config:config HUSH
+//config: bool "hush"
+//config: default y
+//config: help
+//config: hush is a small shell (25k). It handles the normal flow control
+//config: constructs such as if/then/elif/else/fi, for/in/do/done, while loops,
+//config: case/esac. Redirections, here documents, $((arithmetic))
+//config: and functions are supported.
+//config:
+//config: It will compile and work on no-mmu systems.
+//config:
+//config: It does not handle select, aliases, brace expansion,
+//config: tilde expansion, &>file and >&file redirection of stdout+stderr.
+//config:
+//config:config HUSH_BASH_COMPAT
+//config: bool "bash-compatible extensions"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable bash-compatible extensions.
+//config:
+//config:config HUSH_HELP
+//config: bool "help builtin"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable help builtin in hush. Code size + ~1 kbyte.
+//config:
+//config:config HUSH_INTERACTIVE
+//config: bool "Interactive mode"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable interactive mode (prompt and command editing).
+//config: Without this, hush simply reads and executes commands
+//config: from stdin just like a shell script from a file.
+//config: No prompt, no PS1/PS2 magic shell variables.
+//config:
+//config:config HUSH_JOB
+//config: bool "Job control"
+//config: default y
+//config: depends on HUSH_INTERACTIVE
+//config: help
+//config: Enable job control: Ctrl-Z backgrounds, Ctrl-C interrupts current
+//config: command (not entire shell), fg/bg builtins work. Without this option,
+//config: "cmd &" still works by simply spawning a process and immediately
+//config: prompting for next command (or executing next command in a script),
+//config: but no separate process group is formed.
+//config:
+//config:config HUSH_TICK
+//config: bool "Process substitution"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable process substitution `command` and $(command) in hush.
+//config:
+//config:config HUSH_IF
+//config: bool "Support if/then/elif/else/fi"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable if/then/elif/else/fi in hush.
+//config:
+//config:config HUSH_LOOPS
+//config: bool "Support for, while and until loops"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable for, while and until loops in hush.
+//config:
+//config:config HUSH_CASE
+//config: bool "Support case ... esac statement"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable case ... esac statement in hush. +400 bytes.
+//config:
+//config:config HUSH_FUNCTIONS
+//config: bool "Support funcname() { commands; } syntax"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable support for shell functions in hush. +800 bytes.
+//config:
+//config:config HUSH_LOCAL
+//config: bool "Support local builtin"
+//config: default y
+//config: depends on HUSH_FUNCTIONS
+//config: help
+//config: Enable support for local variables in functions.
+//config:
+//config:config HUSH_RANDOM_SUPPORT
+//config: bool "Pseudorandom generator and $RANDOM variable"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: Enable pseudorandom generator and dynamic variable "$RANDOM".
+//config: Each read of "$RANDOM" will generate a new pseudorandom value.
+//config:
+//config:config HUSH_EXPORT_N
+//config: bool "Support 'export -n' option"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: export -n unexports variables. It is a bash extension.
+//config:
+//config:config HUSH_MODE_X
+//config: bool "Support 'hush -x' option and 'set -x' command"
+//config: default y
+//config: depends on HUSH
+//config: help
+//config: This instructs hush to print commands before execution.
+//config: Adds ~300 bytes.
+//config:
+//config:config MSH
+//config: bool "msh (deprecated: aliased to hush)"
+//config: default n
+//config: select HUSH
+//config: help
+//config: msh is deprecated and will be removed, please migrate to hush.
+//config:
+
+//usage:#define hush_trivial_usage NOUSAGE_STR
+//usage:#define hush_full_usage ""
+//usage:#define msh_trivial_usage NOUSAGE_STR
+//usage:#define msh_full_usage ""
+
/* Build knobs */
#define LEAK_HUNTING 0
#define _SPECIAL_VARS_STR "_*@$!?#"
#define SPECIAL_VARS_STR ("_*@$!?#" + 1)
#define NUMERIC_SPECVARS_STR ("_*@$!?#" + 3)
+#if ENABLE_HUSH_BASH_COMPAT
+/* Support / and // replace ops */
+/* Note that // is stored as \ in "encoded" string representation */
+# define VAR_ENCODED_SUBST_OPS "\\/%#:-=+?"
+# define VAR_SUBST_OPS ("\\/%#:-=+?" + 1)
+# define MINUS_PLUS_EQUAL_QUESTION ("\\/%#:-=+?" + 5)
+#else
+# define VAR_ENCODED_SUBST_OPS "%#:-=+?"
+# define VAR_SUBST_OPS "%#:-=+?"
+# define MINUS_PLUS_EQUAL_QUESTION ("%#:-=+?" + 3)
+#endif
#define SPECIAL_VAR_SYMBOL 3
} nommu_save_t;
#endif
-typedef enum reserved_style {
+enum {
RES_NONE = 0,
#if ENABLE_HUSH_IF
RES_IF ,
#endif
RES_XXXX ,
RES_SNTX
-} reserved_style;
+};
+
+enum {
+ EXP_FLAG_GLOB = 0x200,
+ EXP_FLAG_ESC_GLOB_CHARS = 0x100,
+ EXP_FLAG_SINGLEWORD = 0x80, /* must be 0x80 */
+};
typedef struct o_string {
char *data;
int maxlen;
/* Protect newly added chars against globbing
* (by prepending \ to *, ?, [, \) */
- smallint o_escape;
- smallint o_glob;
+ int o_expflags;
/* At least some part of the string was inside '' or "",
* possibly empty one: word"", wo''rd etc. */
- smallint o_quoted;
+ smallint has_quoted_part;
smallint has_empty_slot;
smallint o_assignment; /* 0:maybe, 1:yes, 2:no */
} o_string;
smallint cmd_type; /* CMD_xxx */
#define CMD_NORMAL 0
#define CMD_SUBSHELL 1
-
-/* used for "[[ EXPR ]]" */
#if ENABLE_HUSH_BASH_COMPAT
+/* used for "[[ EXPR ]]" */
# define CMD_SINGLEWORD_NOGLOB 2
#endif
-
-/* used for "export noglob=* glob* a=`echo a b`" */
-//#define CMD_SINGLEWORD_NOGLOB_COND 3
-// It is hard to implement correctly, it adds significant amounts of tricky code,
-// and all this is only useful for really obscure export statements
-// almost nobody would use anyway. #ifdef CMD_SINGLEWORD_NOGLOB_COND
-// guards the code which implements it, but I have doubts it works
-// in all cases (especially with mixed globbed/non-globbed arguments)
-
#if ENABLE_HUSH_FUNCTIONS
# define CMD_FUNCDEF 3
#endif
*/
smallint flag_return_in_progress;
#endif
- smallint fake_mode;
+ smallint n_mode;
+#if ENABLE_HUSH_MODE_X
smallint x_mode;
+# define G_x_mode (G.x_mode)
+#else
+# define G_x_mode 0
+#endif
smallint exiting; /* used to prevent EXIT trap recursion */
/* These four support $?, $#, and $1 */
smalluint last_exitcode;
const char *cwd;
struct variable *top_var; /* = &G.shell_ver (set in main()) */
struct variable shell_ver;
+ char **expanded_assignments;
#if ENABLE_HUSH_FUNCTIONS
struct function *top_func;
# if ENABLE_HUSH_LOCAL
/* Prevent recursion:
* trap "echo Hi; exit" EXIT; exit
*/
- char *argv[] = { NULL, G.traps[0], NULL };
+ char *argv[3];
+ /* argv[0] is unused */
+ argv[1] = G.traps[0];
+ argv[2] = NULL;
G.traps[0] = NULL;
G.exiting = 1;
builtin_eval(argv);
- free(argv[1]);
+ /* free(argv[1]); - why bother */
}
#if ENABLE_HUSH_JOB
if (G.traps && G.traps[sig]) {
if (G.traps[sig][0]) {
/* We have user-defined handler */
- char *argv[] = { NULL, xstrdup(G.traps[sig]), NULL };
+ char *argv[3];
+ /* argv[0] is unused */
+ argv[1] = G.traps[sig];
+ argv[2] = NULL;
save_rcode = G.last_exitcode;
builtin_eval(argv);
- free(argv[1]);
G.last_exitcode = save_rcode;
} /* else: "" trap, ignoring signal */
continue;
/*
* Shell and environment variable support
*/
-static struct variable **get_ptr_to_local_var(const char *name)
+static struct variable **get_ptr_to_local_var(const char *name, unsigned len)
{
struct variable **pp;
struct variable *cur;
- int len;
- len = strlen(name);
pp = &G.top_var;
while ((cur = *pp) != NULL) {
if (strncmp(cur->varstr, name, len) == 0 && cur->varstr[len] == '=')
return NULL;
}
-static struct variable *get_local_var(const char *name)
-{
- struct variable **pp = get_ptr_to_local_var(name);
- if (pp)
- return *pp;
- return NULL;
-}
-
static const char* FAST_FUNC get_local_var_value(const char *name)
{
- struct variable **pp = get_ptr_to_local_var(name);
- if (pp)
- return strchr((*pp)->varstr, '=') + 1;
+ struct variable **vpp;
+ unsigned len = strlen(name);
+
+ if (G.expanded_assignments) {
+ char **cpp = G.expanded_assignments;
+ while (*cpp) {
+ char *cp = *cpp;
+ if (strncmp(cp, name, len) == 0 && cp[len] == '=')
+ return cp + len + 1;
+ cpp++;
+ }
+ }
+
+ vpp = get_ptr_to_local_var(name, len);
+ if (vpp)
+ return (*vpp)->varstr + len + 1;
+
if (strcmp(name, "PPID") == 0)
return utoa(G.root_ppid);
// bash compat: UID? EUID?
#if ENABLE_HUSH_RANDOM_SUPPORT
- if (strcmp(name, "RANDOM") == 0) {
+ if (strcmp(name, "RANDOM") == 0)
return utoa(next_random(&G.random_gen));
- }
#endif
return NULL;
}
free(strings);
}
-#if ENABLE_SH_MATH_SUPPORT
-# define is_name(c) ((c) == '_' || isalpha((unsigned char)(c)))
-# define is_in_name(c) ((c) == '_' || isalnum((unsigned char)(c)))
-static char* FAST_FUNC endofname(const char *name)
-{
- char *p;
-
- p = (char *) name;
- if (!is_name(*p))
- return p;
- while (*++p) {
- if (!is_in_name(*p))
- break;
- }
- return p;
-}
-#endif
-
static void FAST_FUNC set_local_var_from_halves(const char *name, const char *val)
{
char *var = xasprintf("%s=%s", name, val);
eq = strchr(*s, '=');
if (eq) {
- *eq = '\0';
- var_pp = get_ptr_to_local_var(*s);
- *eq = '=';
+ var_pp = get_ptr_to_local_var(*s, eq - *s);
if (var_pp) {
/* Remove variable from global linked list */
var_p = *var_pp;
G.PS2 = "> ";
}
-static const char* setup_prompt_string(int promptmode)
+static const char *setup_prompt_string(int promptmode)
{
const char *prompt_str;
debug_printf("setup_prompt_string %d ", promptmode);
static void o_reset_to_empty_unquoted(o_string *o)
{
o->length = 0;
- o->o_quoted = 0;
+ o->has_quoted_part = 0;
if (o->data)
o->data[0] = '\0';
}
static void o_addblock_duplicate_backslash(o_string *o, const char *str, int len)
{
while (len) {
+ len--;
o_addchr(o, *str);
- if (*str++ == '\\'
- && (*str != '*' && *str != '?' && *str != '[')
- ) {
+ if (*str++ == '\\') {
+ /* \z -> \\\z; \<eol> -> \\<eol> */
o_addchr(o, '\\');
+ if (len) {
+ len--;
+ o_addchr(o, '\\');
+ o_addchr(o, *str++);
+ }
}
- len--;
}
}
static void o_addQchr(o_string *o, int ch)
{
int sz = 1;
- if (o->o_escape && strchr("*?[\\" MAYBE_BRACES, ch)) {
+ if ((o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)
+ && strchr("*?[\\" MAYBE_BRACES, ch)
+ ) {
sz++;
o->data[o->length] = '\\';
o->length++;
o->data[o->length] = '\0';
}
-static void o_addQstr(o_string *o, const char *str, int len)
+static void o_addqblock(o_string *o, const char *str, int len)
{
- if (!o->o_escape) {
- o_addblock(o, str, len);
- return;
- }
while (len) {
char ch;
int sz;
}
}
+static void o_addQblock(o_string *o, const char *str, int len)
+{
+ if (!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)) {
+ o_addblock(o, str, len);
+ return;
+ }
+ o_addqblock(o, str, len);
+}
+
+static void o_addQstr(o_string *o, const char *str)
+{
+ o_addQblock(o, str, strlen(str));
+}
+
/* A special kind of o_string for $VAR and `cmd` expansion.
* It contains char* list[] at the beginning, which is grown in 16 element
* increments. Actual string data starts at the next multiple of 16 * (char*).
int i = 0;
indent();
- fprintf(stderr, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d\n",
- prefix, list, n, string_start, o->length, o->maxlen);
+ fprintf(stderr, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d glob:%d quoted:%d escape:%d\n",
+ prefix, list, n, string_start, o->length, o->maxlen,
+ !!(o->o_expflags & EXP_FLAG_GLOB),
+ o->has_quoted_part,
+ !!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
while (i < n) {
indent();
fprintf(stderr, " list[%d]=%d '%s' %p\n", i, (int)list[i],
n, string_len, string_start);
o->has_empty_slot = 0;
}
- list[n] = (char*)(ptrdiff_t)string_len;
+ list[n] = (char*)(uintptr_t)string_len;
return n + 1;
}
char **list = (char**)o->data;
int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
- return ((int)(ptrdiff_t)list[n-1]) + string_start;
+ return ((int)(uintptr_t)list[n-1]) + string_start;
}
#ifdef HUSH_BRACE_EXP
cp++;
continue;
}
- /*{*/ if ((*cp == '}' && depth-- == 0) || (*cp == ',' && depth == 0))
+ if ((*cp == '}' && depth-- == 0) || (*cp == ',' && depth == 0))
break;
- if (*cp++ == '{') /*}*/
+ if (*cp++ == '{')
depth++;
}
while (1) {
if (*begin == '\0')
goto simple_glob;
- if (*begin == '{') /*}*/ {
+ if (*begin == '{') {
/* Find the first sub-pattern and at the same time
* find the rest after the closing brace */
next = next_brace_sub(begin);
/* An illegal expression */
goto simple_glob;
}
- /*{*/ if (*next == '}') {
+ if (*next == '}') {
/* "{abc}" with no commas - illegal
* brace expr, disregard and skip it */
begin = next + 1;
/* Now find the end of the whole brace expression */
rest = next;
- /*{*/ while (*rest != '}') {
+ while (*rest != '}') {
rest = next_brace_sub(rest);
if (rest == NULL) {
/* An illegal expression */
* That's why we re-copy prefix every time (1st memcpy above).
*/
n = glob_brace(new_pattern_buf, o, n);
- /*{*/ if (*next == '}') {
+ if (*next == '}') {
/* We saw the last entry */
break;
}
/* Performs globbing on last list[],
* saving each result as a new list[].
*/
-static int o_glob(o_string *o, int n)
+static int perform_glob(o_string *o, int n)
{
char *pattern, *copy;
- debug_printf_glob("start o_glob: n:%d o->data:%p\n", n, o->data);
+ debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data);
if (!o->data)
return o_save_ptr_helper(o, n);
pattern = o->data + o_get_last_ptr(o, n);
n = glob_brace(copy, o, n);
free(copy);
if (DEBUG_GLOB)
- debug_print_list("o_glob returning", o, n);
+ debug_print_list("perform_glob returning", o, n);
return n;
}
/* Performs globbing on last list[],
* saving each result as a new list[].
*/
-static int o_glob(o_string *o, int n)
+static int perform_glob(o_string *o, int n)
{
glob_t globdata;
int gr;
char *pattern;
- debug_printf_glob("start o_glob: n:%d o->data:%p\n", n, o->data);
+ debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data);
if (!o->data)
return o_save_ptr_helper(o, n);
pattern = o->data + o_get_last_ptr(o, n);
}
globfree(&globdata);
if (DEBUG_GLOB)
- debug_print_list("o_glob returning", o, n);
+ debug_print_list("perform_glob returning", o, n);
return n;
}
#endif /* !HUSH_BRACE_EXP */
-/* If o->o_glob == 1, glob the string so far remembered.
+/* If o->o_expflags & EXP_FLAG_GLOB, glob the string so far remembered.
* Otherwise, just finish current list[] and start new */
static int o_save_ptr(o_string *o, int n)
{
- if (o->o_glob) { /* if globbing is requested */
+ if (o->o_expflags & EXP_FLAG_GLOB) {
/* If o->has_empty_slot, list[n] was already globbed
* (if it was requested back then when it was filled)
* so don't do that again! */
if (!o->has_empty_slot)
- return o_glob(o, n); /* o_save_ptr_helper is inside */
+ return perform_glob(o, n); /* o_save_ptr_helper is inside */
}
return o_save_ptr_helper(o, n);
}
list[--n] = NULL;
while (n) {
n--;
- list[n] = o->data + (int)(ptrdiff_t)list[n] + string_start;
+ list[n] = o->data + (int)(uintptr_t)list[n] + string_start;
}
return list;
}
+static void free_pipe_list(struct pipe *pi);
-/* Expansion can recurse */
-#if ENABLE_HUSH_TICK
-static int process_command_subs(o_string *dest, const char *s);
-#endif
-static char *expand_string_to_string(const char *str);
-#if BB_MMU
-#define parse_stream_dquoted(as_string, dest, input, dquote_end) \
- parse_stream_dquoted(dest, input, dquote_end)
-#endif
-static int parse_stream_dquoted(o_string *as_string,
- o_string *dest,
- struct in_str *input,
- int dquote_end);
+/* Returns pi->next - next pipe in the list */
+static struct pipe *free_pipe(struct pipe *pi)
+{
+ struct pipe *next;
+ int i;
-/* expand_strvec_to_strvec() takes a list of strings, expands
- * all variable references within and returns a pointer to
- * a list of expanded strings, possibly with larger number
- * of strings. (Think VAR="a b"; echo $VAR).
- * This new list is allocated as a single malloc block.
- * NULL-terminated list of char* pointers is at the beginning of it,
- * followed by strings themself.
- * Caller can deallocate entire list by single free(list). */
+ debug_printf_clean("free_pipe (pid %d)\n", getpid());
+ for (i = 0; i < pi->num_cmds; i++) {
+ struct command *command;
+ struct redir_struct *r, *rnext;
-/* Store given string, finalizing the word and starting new one whenever
- * we encounter IFS char(s). This is used for expanding variable values.
- * End-of-string does NOT finalize word: think about 'echo -$VAR-' */
-static int expand_on_ifs(o_string *output, int n, const char *str)
-{
- while (1) {
- int word_len = strcspn(str, G.ifs);
- if (word_len) {
- if (output->o_escape || !output->o_glob)
- o_addQstr(output, str, word_len);
- else /* protect backslashes against globbing up :) */
- o_addblock_duplicate_backslash(output, str, word_len);
- str += word_len;
+ command = &pi->cmds[i];
+ debug_printf_clean(" command %d:\n", i);
+ if (command->argv) {
+ if (DEBUG_CLEAN) {
+ int a;
+ char **p;
+ for (a = 0, p = command->argv; *p; a++, p++) {
+ debug_printf_clean(" argv[%d] = %s\n", a, *p);
+ }
+ }
+ free_strings(command->argv);
+ //command->argv = NULL;
}
- if (!*str) /* EOL - do not finalize word */
- break;
- o_addchr(output, '\0');
- debug_print_list("expand_on_ifs", output, n);
- n = o_save_ptr(output, n);
- str += strspn(str, G.ifs); /* skip ifs chars */
+ /* not "else if": on syntax error, we may have both! */
+ if (command->group) {
+ debug_printf_clean(" begin group (cmd_type:%d)\n",
+ command->cmd_type);
+ free_pipe_list(command->group);
+ debug_printf_clean(" end group\n");
+ //command->group = NULL;
+ }
+ /* else is crucial here.
+ * If group != NULL, child_func is meaningless */
+#if ENABLE_HUSH_FUNCTIONS
+ else if (command->child_func) {
+ debug_printf_exec("cmd %p releases child func at %p\n", command, command->child_func);
+ command->child_func->parent_cmd = NULL;
+ }
+#endif
+#if !BB_MMU
+ free(command->group_as_string);
+ //command->group_as_string = NULL;
+#endif
+ for (r = command->redirects; r; r = rnext) {
+ debug_printf_clean(" redirect %d%s",
+ r->rd_fd, redir_table[r->rd_type].descrip);
+ /* guard against the case >$FOO, where foo is unset or blank */
+ if (r->rd_filename) {
+ debug_printf_clean(" fname:'%s'\n", r->rd_filename);
+ free(r->rd_filename);
+ //r->rd_filename = NULL;
+ }
+ debug_printf_clean(" rd_dup:%d\n", r->rd_dup);
+ rnext = r->next;
+ free(r);
+ }
+ //command->redirects = NULL;
}
- debug_print_list("expand_on_ifs[1]", output, n);
- return n;
+ free(pi->cmds); /* children are an array, they get freed all at once */
+ //pi->cmds = NULL;
+#if ENABLE_HUSH_JOB
+ free(pi->cmdtext);
+ //pi->cmdtext = NULL;
+#endif
+
+ next = pi->next;
+ free(pi);
+ return next;
}
-/* Helper to expand $((...)) and heredoc body. These act as if
- * they are in double quotes, with the exception that they are not :).
- * Just the rules are similar: "expand only $var and `cmd`"
- *
- * Returns malloced string.
- * As an optimization, we return NULL if expansion is not needed.
- */
-static char *expand_pseudo_dquoted(const char *str)
+static void free_pipe_list(struct pipe *pi)
{
- char *exp_str;
- struct in_str input;
- o_string dest = NULL_O_STRING;
-
- if (strchr(str, '$') == NULL
-#if ENABLE_HUSH_TICK
- && strchr(str, '`') == NULL
+ while (pi) {
+#if HAS_KEYWORDS
+ debug_printf_clean("pipe reserved word %d\n", pi->res_word);
#endif
- ) {
- return NULL;
+ debug_printf_clean("pipe followup code %d\n", pi->followup);
+ pi = free_pipe(pi);
}
+}
- /* We need to expand. Example:
- * echo $(($a + `echo 1`)) $((1 + $((2)) ))
- */
- setup_string_in_str(&input, str);
- parse_stream_dquoted(NULL, &dest, &input, EOF);
- //bb_error_msg("'%s' -> '%s'", str, dest.data);
- exp_str = expand_string_to_string(dest.data);
- //bb_error_msg("'%s' -> '%s'", dest.data, exp_str);
- o_free_unsafe(&dest);
- return exp_str;
+
+/*** Parsing routines ***/
+
+static struct pipe *new_pipe(void)
+{
+ struct pipe *pi;
+ pi = xzalloc(sizeof(struct pipe));
+ /*pi->followup = 0; - deliberately invalid value */
+ /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */
+ return pi;
}
-#if ENABLE_SH_MATH_SUPPORT
-static arith_t expand_and_evaluate_arith(const char *arg, int *errcode_p)
+/* Command (member of a pipe) is complete, or we start a new pipe
+ * if ctx->command is NULL.
+ * No errors possible here.
+ */
+static int done_command(struct parse_context *ctx)
{
- arith_eval_hooks_t hooks;
- arith_t res;
- char *exp_str;
+ /* The command is really already in the pipe structure, so
+ * advance the pipe counter and make a new, null command. */
+ struct pipe *pi = ctx->pipe;
+ struct command *command = ctx->command;
- hooks.lookupvar = get_local_var_value;
- hooks.setvar = set_local_var_from_halves;
- hooks.endofname = endofname;
- exp_str = expand_pseudo_dquoted(arg);
- res = arith(exp_str ? exp_str : arg, errcode_p, &hooks);
- free(exp_str);
- return res;
+ if (command) {
+ if (IS_NULL_CMD(command)) {
+ debug_printf_parse("done_command: skipping null cmd, num_cmds=%d\n", pi->num_cmds);
+ goto clear_and_ret;
+ }
+ pi->num_cmds++;
+ debug_printf_parse("done_command: ++num_cmds=%d\n", pi->num_cmds);
+ //debug_print_tree(ctx->list_head, 20);
+ } else {
+ debug_printf_parse("done_command: initializing, num_cmds=%d\n", pi->num_cmds);
+ }
+
+ /* Only real trickiness here is that the uncommitted
+ * command structure is not counted in pi->num_cmds. */
+ pi->cmds = xrealloc(pi->cmds, sizeof(*pi->cmds) * (pi->num_cmds+1));
+ ctx->command = command = &pi->cmds[pi->num_cmds];
+ clear_and_ret:
+ memset(command, 0, sizeof(*command));
+ return pi->num_cmds; /* used only for 0/nonzero check */
}
-#endif
-/* Expand all variable references in given string, adding words to list[]
- * at n, n+1,... positions. Return updated n (so that list[n] is next one
- * to be filled). This routine is extremely tricky: has to deal with
- * variables/parameters with whitespace, $* and $@, and constructs like
- * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
-static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
+static void done_pipe(struct parse_context *ctx, pipe_style type)
{
- /* or_mask is either 0 (normal case) or 0x80 -
- * expansion of right-hand side of assignment == 1-element expand.
- * It will also do no globbing, and thus we must not backslash-quote!
- */
- char ored_ch;
- char *p;
-
- ored_ch = 0;
+ int not_null;
- debug_printf_expand("expand_vars_to_list: arg:'%s' or_mask:%x\n", arg, or_mask);
- debug_print_list("expand_vars_to_list", output, n);
- n = o_save_ptr(output, n);
- debug_print_list("expand_vars_to_list[0]", output, n);
+ debug_printf_parse("done_pipe entered, followup %d\n", type);
+ /* Close previous command */
+ not_null = done_command(ctx);
+ ctx->pipe->followup = type;
+#if HAS_KEYWORDS
+ ctx->pipe->pi_inverted = ctx->ctx_inverted;
+ ctx->ctx_inverted = 0;
+ ctx->pipe->res_word = ctx->ctx_res_w;
+#endif
- while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) {
- char first_ch;
- int i;
- char *to_be_freed = NULL;
- const char *val = NULL;
-#if ENABLE_HUSH_TICK
- o_string subst_result = NULL_O_STRING;
+ /* Without this check, even just <enter> on command line generates
+ * tree of three NOPs (!). Which is harmless but annoying.
+ * IOW: it is safe to do it unconditionally. */
+ if (not_null
+#if ENABLE_HUSH_IF
+ || ctx->ctx_res_w == RES_FI
#endif
-#if ENABLE_SH_MATH_SUPPORT
- char arith_buf[sizeof(arith_t)*3 + 2];
-#endif
- o_addblock(output, arg, p - arg);
- debug_print_list("expand_vars_to_list[1]", output, n);
- arg = ++p;
- p = strchr(p, SPECIAL_VAR_SYMBOL);
-
- first_ch = arg[0] | or_mask; /* forced to "quoted" if or_mask = 0x80 */
- /* "$@" is special. Even if quoted, it can still
- * expand to nothing (not even an empty string) */
- if ((first_ch & 0x7f) != '@')
- ored_ch |= first_ch;
-
- switch (first_ch & 0x7f) {
- /* Highest bit in first_ch indicates that var is double-quoted */
- case '*':
- case '@':
- i = 1;
- if (!G.global_argv[i])
- break;
- ored_ch |= first_ch; /* do it for "$@" _now_, when we know it's not empty */
- if (!(first_ch & 0x80)) { /* unquoted $* or $@ */
- smallint sv = output->o_escape;
- /* unquoted var's contents should be globbed, so don't escape */
- output->o_escape = 0;
- while (G.global_argv[i]) {
- n = expand_on_ifs(output, n, G.global_argv[i]);
- debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1);
- if (G.global_argv[i++][0] && G.global_argv[i]) {
- /* this argv[] is not empty and not last:
- * put terminating NUL, start new word */
- o_addchr(output, '\0');
- debug_print_list("expand_vars_to_list[2]", output, n);
- n = o_save_ptr(output, n);
- debug_print_list("expand_vars_to_list[3]", output, n);
- }
- }
- output->o_escape = sv;
- } else
- /* If or_mask is nonzero, we handle assignment 'a=....$@.....'
- * and in this case should treat it like '$*' - see 'else...' below */
- if (first_ch == ('@'|0x80) && !or_mask) { /* quoted $@ */
- while (1) {
- o_addQstr(output, G.global_argv[i], strlen(G.global_argv[i]));
- if (++i >= G.global_argc)
- break;
- o_addchr(output, '\0');
- debug_print_list("expand_vars_to_list[4]", output, n);
- n = o_save_ptr(output, n);
- }
- } else { /* quoted $*: add as one word */
- while (1) {
- o_addQstr(output, G.global_argv[i], strlen(G.global_argv[i]));
- if (!G.global_argv[++i])
- break;
- if (G.ifs[0])
- o_addchr(output, G.ifs[0]);
- }
- }
- break;
- case SPECIAL_VAR_SYMBOL: /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */
- /* "Empty variable", used to make "" etc to not disappear */
- arg++;
- ored_ch = 0x80;
- break;
-#if ENABLE_HUSH_TICK
- case '`': /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */
- *p = '\0';
- arg++;
- /* Can't just stuff it into output o_string,
- * expanded result may need to be globbed
- * and $IFS-splitted */
- debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch);
- G.last_exitcode = process_command_subs(&subst_result, arg);
- debug_printf_subst("SUBST RES:%d '%s'\n", G.last_exitcode, subst_result.data);
- val = subst_result.data;
- goto store_val;
-#endif
-#if ENABLE_SH_MATH_SUPPORT
- case '+': { /* <SPECIAL_VAR_SYMBOL>+cmd<SPECIAL_VAR_SYMBOL> */
- arith_t res;
- int errcode;
-
- arg++; /* skip '+' */
- *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
- debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch);
- res = expand_and_evaluate_arith(arg, &errcode);
-
- if (errcode < 0) {
- const char *msg = "error in arithmetic";
- switch (errcode) {
- case -3:
- msg = "exponent less than 0";
- break;
- case -2:
- msg = "divide by 0";
- break;
- case -5:
- msg = "expression recursion loop detected";
- break;
- }
- die_if_script(msg);
- }
- debug_printf_subst("ARITH RES '"arith_t_fmt"'\n", res);
- sprintf(arith_buf, arith_t_fmt, res);
- val = arith_buf;
- break;
- }
+#if ENABLE_HUSH_LOOPS
+ || ctx->ctx_res_w == RES_DONE
+ || ctx->ctx_res_w == RES_FOR
+ || ctx->ctx_res_w == RES_IN
#endif
- default: { /* <SPECIAL_VAR_SYMBOL>varname<SPECIAL_VAR_SYMBOL> */
- char *var;
- char first_char;
- char exp_op;
- char exp_save = exp_save; /* for compiler */
- char *exp_saveptr; /* points to expansion operator */
- char *exp_word = exp_word; /* for compiler */
-
- var = arg;
- *p = '\0';
- exp_saveptr = arg[1] ? strchr("%#:-=+?", arg[1]) : NULL;
- first_char = arg[0] = first_ch & 0x7f;
- exp_op = 0;
-
- if (first_char == '#' && arg[1] && !exp_saveptr) {
- /* handle length expansion ${#var} */
- var++;
- exp_op = 'L';
- } else {
- /* maybe handle parameter expansion */
- if (exp_saveptr /* if 2nd char is one of expansion operators */
- && strchr(NUMERIC_SPECVARS_STR, first_char) /* 1st char is special variable */
- ) {
- /* ${?:0}, ${#[:]%0} etc */
- exp_saveptr = var + 1;
- } else {
- /* ${?}, ${var}, ${var:0}, ${var[:]%0} etc */
- exp_saveptr = var+1 + strcspn(var+1, "%#:-=+?");
- }
- exp_op = exp_save = *exp_saveptr;
- if (exp_op) {
- exp_word = exp_saveptr + 1;
- if (exp_op == ':') {
- exp_op = *exp_word++;
- if (ENABLE_HUSH_BASH_COMPAT
- && (exp_op == '\0' || !strchr("%#:-=+?"+3, exp_op))
- ) {
- /* oops... it's ${var:N[:M]}, not ${var:?xxx} or some such */
- exp_op = ':';
- exp_word--;
- }
- }
- *exp_saveptr = '\0';
- } /* else: it's not an expansion op, but bare ${var} */
- }
-
- /* lookup the variable in question */
- if (isdigit(var[0])) {
- /* parse_dollar() should have vetted var for us */
- i = xatoi_u(var);
- if (i < G.global_argc)
- val = G.global_argv[i];
- /* else val remains NULL: $N with too big N */
- } else {
- switch (var[0]) {
- case '$': /* pid */
- val = utoa(G.root_pid);
- break;
- case '!': /* bg pid */
- val = G.last_bg_pid ? utoa(G.last_bg_pid) : (char*)"";
- break;
- case '?': /* exitcode */
- val = utoa(G.last_exitcode);
- break;
- case '#': /* argc */
- val = utoa(G.global_argc ? G.global_argc-1 : 0);
- break;
- default:
- val = get_local_var_value(var);
- }
- }
-
- /* handle any expansions */
- if (exp_op == 'L') {
- debug_printf_expand("expand: length(%s)=", val);
- val = utoa(val ? strlen(val) : 0);
- debug_printf_expand("%s\n", val);
- } else if (exp_op) {
- if (exp_op == '%' || exp_op == '#') {
- /* Standard-mandated substring removal ops:
- * ${parameter%word} - remove smallest suffix pattern
- * ${parameter%%word} - remove largest suffix pattern
- * ${parameter#word} - remove smallest prefix pattern
- * ${parameter##word} - remove largest prefix pattern
- *
- * Word is expanded to produce a glob pattern.
- * Then var's value is matched to it and matching part removed.
- */
- if (val) {
- bool match_at_left;
- char *loc;
- scan_t scan = pick_scan(exp_op, *exp_word, &match_at_left);
- if (exp_op == *exp_word) /* ## or %% */
- exp_word++;
- val = to_be_freed = xstrdup(val);
- {
- char *exp_exp_word = expand_pseudo_dquoted(exp_word);
- if (exp_exp_word)
- exp_word = exp_exp_word;
- loc = scan(to_be_freed, exp_word, match_at_left);
- //bb_error_msg("op:%c str:'%s' pat:'%s' res:'%s'",
- // exp_op, to_be_freed, exp_word, loc);
- free(exp_exp_word);
- }
- if (loc) { /* match was found */
- if (match_at_left) /* # or ## */
- val = loc;
- else /* % or %% */
- *loc = '\0';
- }
- }
- } else if (exp_op == ':') {
-#if ENABLE_HUSH_BASH_COMPAT && ENABLE_SH_MATH_SUPPORT
- /* It's ${var:N[:M]} bashism.
- * Note that in encoded form it has TWO parts:
- * var:N<SPECIAL_VAR_SYMBOL>M<SPECIAL_VAR_SYMBOL>
- */
- arith_t beg, len;
- int errcode = 0;
-
- beg = expand_and_evaluate_arith(exp_word, &errcode);
- debug_printf_varexp("beg:'%s'=%lld\n", exp_word, (long long)beg);
- *p++ = SPECIAL_VAR_SYMBOL;
- exp_word = p;
- p = strchr(p, SPECIAL_VAR_SYMBOL);
- *p = '\0';
- len = expand_and_evaluate_arith(exp_word, &errcode);
- debug_printf_varexp("len:'%s'=%lld\n", exp_word, (long long)len);
-
- if (errcode >= 0 && len >= 0) { /* bash compat: len < 0 is illegal */
- if (beg < 0) /* bash compat */
- beg = 0;
- debug_printf_varexp("from val:'%s'\n", val);
- if (len == 0 || !val || beg >= strlen(val))
- val = "";
- else {
- /* Paranoia. What if user entered 9999999999999
- * which fits in arith_t but not int? */
- if (len >= INT_MAX)
- len = INT_MAX;
- val = to_be_freed = xstrndup(val + beg, len);
- }
- debug_printf_varexp("val:'%s'\n", val);
- } else
+#if ENABLE_HUSH_CASE
+ || ctx->ctx_res_w == RES_ESAC
#endif
- {
- die_if_script("malformed ${%s:...}", var);
- val = "";
- }
- } else { /* one of "-=+?" */
- /* Standard-mandated substitution ops:
- * ${var?word} - indicate error if unset
- * If var is unset, word (or a message indicating it is unset
- * if word is null) is written to standard error
- * and the shell exits with a non-zero exit status.
- * Otherwise, the value of var is substituted.
- * ${var-word} - use default value
- * If var is unset, word is substituted.
- * ${var=word} - assign and use default value
- * If var is unset, word is assigned to var.
- * In all cases, final value of var is substituted.
- * ${var+word} - use alternative value
- * If var is unset, null is substituted.
- * Otherwise, word is substituted.
- *
- * Word is subjected to tilde expansion, parameter expansion,
- * command substitution, and arithmetic expansion.
- * If word is not needed, it is not expanded.
- *
- * Colon forms (${var:-word}, ${var:=word} etc) do the same,
- * but also treat null var as if it is unset.
- */
- int use_word = (!val || ((exp_save == ':') && !val[0]));
- if (exp_op == '+')
- use_word = !use_word;
- debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op,
- (exp_save == ':') ? "true" : "false", use_word);
- if (use_word) {
- to_be_freed = expand_pseudo_dquoted(exp_word);
- if (to_be_freed)
- exp_word = to_be_freed;
- if (exp_op == '?') {
- /* mimic bash message */
- die_if_script("%s: %s",
- var,
- exp_word[0] ? exp_word : "parameter null or not set"
- );
-//TODO: how interactive bash aborts expansion mid-command?
- } else {
- val = exp_word;
- }
-
- if (exp_op == '=') {
- /* ${var=[word]} or ${var:=[word]} */
- if (isdigit(var[0]) || var[0] == '#') {
- /* mimic bash message */
- die_if_script("$%s: cannot assign in this way", var);
- val = NULL;
- } else {
- char *new_var = xasprintf("%s=%s", var, val);
- set_local_var(new_var, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
- }
- }
- }
- } /* one of "-=+?" */
-
- *exp_saveptr = exp_save;
- } /* if (exp_op) */
-
- arg[0] = first_ch;
-#if ENABLE_HUSH_TICK
- store_val:
+ ) {
+ struct pipe *new_p;
+ debug_printf_parse("done_pipe: adding new pipe: "
+ "not_null:%d ctx->ctx_res_w:%d\n",
+ not_null, ctx->ctx_res_w);
+ new_p = new_pipe();
+ ctx->pipe->next = new_p;
+ ctx->pipe = new_p;
+ /* RES_THEN, RES_DO etc are "sticky" -
+ * they remain set for pipes inside if/while.
+ * This is used to control execution.
+ * RES_FOR and RES_IN are NOT sticky (needed to support
+ * cases where variable or value happens to match a keyword):
+ */
+#if ENABLE_HUSH_LOOPS
+ if (ctx->ctx_res_w == RES_FOR
+ || ctx->ctx_res_w == RES_IN)
+ ctx->ctx_res_w = RES_NONE;
#endif
- if (!(first_ch & 0x80)) { /* unquoted $VAR */
- debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val, output->o_escape);
- if (val) {
- /* unquoted var's contents should be globbed, so don't escape */
- smallint sv = output->o_escape;
- output->o_escape = 0;
- n = expand_on_ifs(output, n, val);
- val = NULL;
- output->o_escape = sv;
- }
- } else { /* quoted $VAR, val will be appended below */
- debug_printf_expand("quoted '%s', output->o_escape:%d\n", val, output->o_escape);
- }
- } /* default: */
- } /* switch (char after <SPECIAL_VAR_SYMBOL>) */
-
- if (val) {
- o_addQstr(output, val, strlen(val));
- }
- free(to_be_freed);
- /* Do the check to avoid writing to a const string */
- if (*p != SPECIAL_VAR_SYMBOL)
- *p = SPECIAL_VAR_SYMBOL;
-
-#if ENABLE_HUSH_TICK
- o_free(&subst_result);
+#if ENABLE_HUSH_CASE
+ if (ctx->ctx_res_w == RES_MATCH)
+ ctx->ctx_res_w = RES_CASE_BODY;
+ if (ctx->ctx_res_w == RES_CASE)
+ ctx->ctx_res_w = RES_CASE_IN;
#endif
- arg = ++p;
- } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */
-
- if (arg[0]) {
- debug_print_list("expand_vars_to_list[a]", output, n);
- /* this part is literal, and it was already pre-quoted
- * if needed (much earlier), do not use o_addQstr here! */
- o_addstr_with_NUL(output, arg);
- debug_print_list("expand_vars_to_list[b]", output, n);
- } else if (output->length == o_get_last_ptr(output, n) /* expansion is empty */
- && !(ored_ch & 0x80) /* and all vars were not quoted. */
- ) {
- n--;
- /* allow to reuse list[n] later without re-growth */
- output->has_empty_slot = 1;
- } else {
- o_addchr(output, '\0');
- }
- return n;
-}
-
-static char **expand_variables(char **argv, int or_mask)
-{
- int n;
- char **list;
- char **v;
- o_string output = NULL_O_STRING;
-
- if (or_mask & 0x100) {
- output.o_escape = 1; /* protect against globbing for "$var" */
- /* (unquoted $var will temporarily switch it off) */
- output.o_glob = 1;
- }
-
- n = 0;
- v = argv;
- while (*v) {
- n = expand_vars_to_list(&output, n, *v, (unsigned char)or_mask);
- v++;
+ ctx->command = NULL; /* trick done_command below */
+ /* Create the memory for command, roughly:
+ * ctx->pipe->cmds = new struct command;
+ * ctx->command = &ctx->pipe->cmds[0];
+ */
+ done_command(ctx);
+ //debug_print_tree(ctx->list_head, 10);
}
- debug_print_list("expand_variables", &output, n);
-
- /* output.data (malloced in one block) gets returned in "list" */
- list = o_finalize_list(&output, n);
- debug_print_strings("expand_variables[1]", list);
- return list;
-}
-
-static char **expand_strvec_to_strvec(char **argv)
-{
- return expand_variables(argv, 0x100);
+ debug_printf_parse("done_pipe return\n");
}
-#if ENABLE_HUSH_BASH_COMPAT
-static char **expand_strvec_to_strvec_singleword_noglob(char **argv)
+static void initialize_context(struct parse_context *ctx)
{
- return expand_variables(argv, 0x80);
+ memset(ctx, 0, sizeof(*ctx));
+ ctx->pipe = ctx->list_head = new_pipe();
+ /* Create the memory for command, roughly:
+ * ctx->pipe->cmds = new struct command;
+ * ctx->command = &ctx->pipe->cmds[0];
+ */
+ done_command(ctx);
}
-#endif
-
-#ifdef CMD_SINGLEWORD_NOGLOB_COND
-static char **expand_strvec_to_strvec_singleword_noglob_cond(char **argv)
-{
- int n;
- char **list;
- char **v;
- o_string output = NULL_O_STRING;
-
- n = 0;
- v = argv;
- while (*v) {
- int is_var = is_well_formed_var_name(*v, '=');
- /* is_var * 0x80: singleword expansion for vars */
- n = expand_vars_to_list(&output, n, *v, is_var * 0x80);
- /* Subtle! expand_vars_to_list did not glob last word yet.
- * It does this only when fed with further data.
- * Therefore we set globbing flags AFTER it, not before:
- */
-
- /* if it is not recognizably abc=...; then: */
- output.o_escape = !is_var; /* protect against globbing for "$var" */
- /* (unquoted $var will temporarily switch it off) */
- output.o_glob = !is_var; /* and indeed do globbing */
- v++;
- }
- debug_print_list("expand_cond", &output, n);
-
- /* output.data (malloced in one block) gets returned in "list" */
- list = o_finalize_list(&output, n);
- debug_print_strings("expand_cond[1]", list);
- return list;
-}
-#endif
+/* If a reserved word is found and processed, parse context is modified
+ * and 1 is returned.
+ */
+#if HAS_KEYWORDS
+struct reserved_combo {
+ char literal[6];
+ unsigned char res;
+ unsigned char assignment_flag;
+ int flag;
+};
+enum {
+ FLAG_END = (1 << RES_NONE ),
+# if ENABLE_HUSH_IF
+ FLAG_IF = (1 << RES_IF ),
+ FLAG_THEN = (1 << RES_THEN ),
+ FLAG_ELIF = (1 << RES_ELIF ),
+ FLAG_ELSE = (1 << RES_ELSE ),
+ FLAG_FI = (1 << RES_FI ),
+# endif
+# if ENABLE_HUSH_LOOPS
+ FLAG_FOR = (1 << RES_FOR ),
+ FLAG_WHILE = (1 << RES_WHILE),
+ FLAG_UNTIL = (1 << RES_UNTIL),
+ FLAG_DO = (1 << RES_DO ),
+ FLAG_DONE = (1 << RES_DONE ),
+ FLAG_IN = (1 << RES_IN ),
+# endif
+# if ENABLE_HUSH_CASE
+ FLAG_MATCH = (1 << RES_MATCH),
+ FLAG_ESAC = (1 << RES_ESAC ),
+# endif
+ FLAG_START = (1 << RES_XXXX ),
+};
-/* Used for expansion of right hand of assignments */
-/* NB: should NOT do globbing! "export v=/bin/c*; env | grep ^v=" outputs
- * "v=/bin/c*" */
-static char *expand_string_to_string(const char *str)
+static const struct reserved_combo* match_reserved_word(o_string *word)
{
- char *argv[2], **list;
+ /* Mostly a list of accepted follow-up reserved words.
+ * FLAG_END means we are done with the sequence, and are ready
+ * to turn the compound list into a command.
+ * FLAG_START means the word must start a new compound list.
+ */
+ static const struct reserved_combo reserved_list[] = {
+# if ENABLE_HUSH_IF
+ { "!", RES_NONE, NOT_ASSIGNMENT , 0 },
+ { "if", RES_IF, WORD_IS_KEYWORD, FLAG_THEN | FLAG_START },
+ { "then", RES_THEN, WORD_IS_KEYWORD, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
+ { "elif", RES_ELIF, WORD_IS_KEYWORD, FLAG_THEN },
+ { "else", RES_ELSE, WORD_IS_KEYWORD, FLAG_FI },
+ { "fi", RES_FI, NOT_ASSIGNMENT , FLAG_END },
+# endif
+# if ENABLE_HUSH_LOOPS
+ { "for", RES_FOR, NOT_ASSIGNMENT , FLAG_IN | FLAG_DO | FLAG_START },
+ { "while", RES_WHILE, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
+ { "until", RES_UNTIL, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
+ { "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO },
+ { "do", RES_DO, WORD_IS_KEYWORD, FLAG_DONE },
+ { "done", RES_DONE, NOT_ASSIGNMENT , FLAG_END },
+# endif
+# if ENABLE_HUSH_CASE
+ { "case", RES_CASE, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_START },
+ { "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END },
+# endif
+ };
+ const struct reserved_combo *r;
- argv[0] = (char*)str;
- argv[1] = NULL;
- list = expand_variables(argv, 0x80); /* 0x80: singleword expansion */
- if (HUSH_DEBUG)
- if (!list[0] || list[1])
- bb_error_msg_and_die("BUG in varexp2");
- /* actually, just move string 2*sizeof(char*) bytes back */
- overlapping_strcpy((char*)list, list[0]);
- unbackslash((char*)list);
- debug_printf_expand("string_to_string='%s'\n", (char*)list);
- return (char*)list;
+ for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) {
+ if (strcmp(word->data, r->literal) == 0)
+ return r;
+ }
+ return NULL;
}
-
-/* Used for "eval" builtin */
-static char* expand_strvec_to_string(char **argv)
+/* Return 0: not a keyword, 1: keyword
+ */
+static int reserved_word(o_string *word, struct parse_context *ctx)
{
- char **list;
+# if ENABLE_HUSH_CASE
+ static const struct reserved_combo reserved_match = {
+ "", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC
+ };
+# endif
+ const struct reserved_combo *r;
- list = expand_variables(argv, 0x80);
- /* Convert all NULs to spaces */
- if (list[0]) {
- int n = 1;
- while (list[n]) {
- if (HUSH_DEBUG)
- if (list[n-1] + strlen(list[n-1]) + 1 != list[n])
- bb_error_msg_and_die("BUG in varexp3");
- /* bash uses ' ' regardless of $IFS contents */
- list[n][-1] = ' ';
- n++;
+ if (word->has_quoted_part)
+ return 0;
+ r = match_reserved_word(word);
+ if (!r)
+ return 0;
+
+ debug_printf("found reserved word %s, res %d\n", r->literal, r->res);
+# if ENABLE_HUSH_CASE
+ if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE_IN) {
+ /* "case word IN ..." - IN part starts first MATCH part */
+ r = &reserved_match;
+ } else
+# endif
+ if (r->flag == 0) { /* '!' */
+ if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */
+ syntax_error("! ! command");
+ ctx->ctx_res_w = RES_SNTX;
}
+ ctx->ctx_inverted = 1;
+ return 1;
}
- overlapping_strcpy((char*)list, list[0]);
- debug_printf_expand("strvec_to_string='%s'\n", (char*)list);
- return (char*)list;
-}
+ if (r->flag & FLAG_START) {
+ struct parse_context *old;
-static char **expand_assignments(char **argv, int count)
-{
- int i;
- char **p = NULL;
- /* Expand assignments into one string each */
- for (i = 0; i < count; i++) {
- p = add_string_to_strings(p, expand_string_to_string(argv[i]));
+ old = xmalloc(sizeof(*old));
+ debug_printf_parse("push stack %p\n", old);
+ *old = *ctx; /* physical copy */
+ initialize_context(ctx);
+ ctx->stack = old;
+ } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) {
+ syntax_error_at(word->data);
+ ctx->ctx_res_w = RES_SNTX;
+ return 1;
+ } else {
+ /* "{...} fi" is ok. "{...} if" is not
+ * Example:
+ * if { echo foo; } then { echo bar; } fi */
+ if (ctx->command->group)
+ done_pipe(ctx, PIPE_SEQ);
}
- return p;
-}
-
-
-#if BB_MMU
-/* never called */
-void re_execute_shell(char ***to_free, const char *s,
- char *g_argv0, char **g_argv,
- char **builtin_argv) NORETURN;
-
-static void reset_traps_to_defaults(void)
-{
- /* This function is always called in a child shell
- * after fork (not vfork, NOMMU doesn't use this function).
- */
- unsigned sig;
- unsigned mask;
- /* Child shells are not interactive.
- * SIGTTIN/SIGTTOU/SIGTSTP should not have special handling.
- * Testcase: (while :; do :; done) + ^Z should background.
- * Same goes for SIGTERM, SIGHUP, SIGINT.
- */
- if (!G.traps && !(G.non_DFL_mask & SPECIAL_INTERACTIVE_SIGS))
- return; /* already no traps and no SPECIAL_INTERACTIVE_SIGS */
+ ctx->ctx_res_w = r->res;
+ ctx->old_flag = r->flag;
+ word->o_assignment = r->assignment_flag;
- /* Switching off SPECIAL_INTERACTIVE_SIGS.
- * Stupid. It can be done with *single* &= op, but we can't use
- * the fact that G.blocked_set is implemented as a bitmask
- * in libc... */
- mask = (SPECIAL_INTERACTIVE_SIGS >> 1);
- sig = 1;
- while (1) {
- if (mask & 1) {
- /* Careful. Only if no trap or trap is not "" */
- if (!G.traps || !G.traps[sig] || G.traps[sig][0])
- sigdelset(&G.blocked_set, sig);
- }
- mask >>= 1;
- if (!mask)
- break;
- sig++;
- }
- /* Our homegrown sig mask is saner to work with :) */
- G.non_DFL_mask &= ~SPECIAL_INTERACTIVE_SIGS;
+ if (ctx->old_flag & FLAG_END) {
+ struct parse_context *old;
- /* Resetting all traps to default except empty ones */
- mask = G.non_DFL_mask;
- if (G.traps) for (sig = 0; sig < NSIG; sig++, mask >>= 1) {
- if (!G.traps[sig] || !G.traps[sig][0])
- continue;
- free(G.traps[sig]);
- G.traps[sig] = NULL;
- /* There is no signal for 0 (EXIT) */
- if (sig == 0)
- continue;
- /* There was a trap handler, we just removed it.
- * But if sig still has non-DFL handling,
- * we should not unblock the sig. */
- if (mask & 1)
- continue;
- sigdelset(&G.blocked_set, sig);
+ done_pipe(ctx, PIPE_SEQ);
+ debug_printf_parse("pop stack %p\n", ctx->stack);
+ old = ctx->stack;
+ old->command->group = ctx->list_head;
+ old->command->cmd_type = CMD_NORMAL;
+# if !BB_MMU
+ o_addstr(&old->as_string, ctx->as_string.data);
+ o_free_unsafe(&ctx->as_string);
+ old->command->group_as_string = xstrdup(old->as_string.data);
+ debug_printf_parse("pop, remembering as:'%s'\n",
+ old->command->group_as_string);
+# endif
+ *ctx = *old; /* physical copy */
+ free(old);
}
- sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
+ return 1;
}
+#endif /* HAS_KEYWORDS */
-#else /* !BB_MMU */
-
-static void re_execute_shell(char ***to_free, const char *s,
- char *g_argv0, char **g_argv,
- char **builtin_argv) NORETURN;
-static void re_execute_shell(char ***to_free, const char *s,
- char *g_argv0, char **g_argv,
- char **builtin_argv)
+/* Word is complete, look at it and update parsing context.
+ * Normal return is 0. Syntax errors return 1.
+ * Note: on return, word is reset, but not o_free'd!
+ */
+static int done_word(o_string *word, struct parse_context *ctx)
{
-# define NOMMU_HACK_FMT ("-$%x:%x:%x:%x:%x:%llx" IF_HUSH_LOOPS(":%x"))
- /* delims + 2 * (number of bytes in printed hex numbers) */
- char param_buf[sizeof(NOMMU_HACK_FMT) + 2 * (sizeof(int)*6 + sizeof(long long)*1)];
- char *heredoc_argv[4];
- struct variable *cur;
-# if ENABLE_HUSH_FUNCTIONS
- struct function *funcp;
-# endif
- char **argv, **pp;
- unsigned cnt;
- unsigned long long empty_trap_mask;
+ struct command *command = ctx->command;
- if (!g_argv0) { /* heredoc */
- argv = heredoc_argv;
- argv[0] = (char *) G.argv0_for_re_execing;
- argv[1] = (char *) "-<";
- argv[2] = (char *) s;
- argv[3] = NULL;
- pp = &argv[3]; /* used as pointer to empty environment */
- goto do_exec;
+ debug_printf_parse("done_word entered: '%s' %p\n", word->data, command);
+ if (word->length == 0 && !word->has_quoted_part) {
+ debug_printf_parse("done_word return 0: true null, ignored\n");
+ return 0;
}
- cnt = 0;
- pp = builtin_argv;
- if (pp) while (*pp++)
- cnt++;
-
- empty_trap_mask = 0;
- if (G.traps) {
- int sig;
- for (sig = 1; sig < NSIG; sig++) {
- if (G.traps[sig] && !G.traps[sig][0])
- empty_trap_mask |= 1LL << sig;
+ if (ctx->pending_redirect) {
+ /* We do not glob in e.g. >*.tmp case. bash seems to glob here
+ * only if run as "bash", not "sh" */
+ /* http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
+ * "2.7 Redirection
+ * ...the word that follows the redirection operator
+ * shall be subjected to tilde expansion, parameter expansion,
+ * command substitution, arithmetic expansion, and quote
+ * removal. Pathname expansion shall not be performed
+ * on the word by a non-interactive shell; an interactive
+ * shell may perform it, but shall do so only when
+ * the expansion would result in one word."
+ */
+ ctx->pending_redirect->rd_filename = xstrdup(word->data);
+ /* Cater for >\file case:
+ * >\a creates file a; >\\a, >"\a", >"\\a" create file \a
+ * Same with heredocs:
+ * for <<\H delim is H; <<\\H, <<"\H", <<"\\H" - \H
+ */
+ if (ctx->pending_redirect->rd_type == REDIRECT_HEREDOC) {
+ unbackslash(ctx->pending_redirect->rd_filename);
+ /* Is it <<"HEREDOC"? */
+ if (word->has_quoted_part) {
+ ctx->pending_redirect->rd_dup |= HEREDOC_QUOTED;
+ }
+ }
+ debug_printf_parse("word stored in rd_filename: '%s'\n", word->data);
+ ctx->pending_redirect = NULL;
+ } else {
+ /* If this word wasn't an assignment, next ones definitely
+ * can't be assignments. Even if they look like ones. */
+ if (word->o_assignment != DEFINITELY_ASSIGNMENT
+ && word->o_assignment != WORD_IS_KEYWORD
+ ) {
+ word->o_assignment = NOT_ASSIGNMENT;
+ } else {
+ if (word->o_assignment == DEFINITELY_ASSIGNMENT)
+ command->assignment_cnt++;
+ word->o_assignment = MAYBE_ASSIGNMENT;
}
- }
- sprintf(param_buf, NOMMU_HACK_FMT
- , (unsigned) G.root_pid
- , (unsigned) G.root_ppid
- , (unsigned) G.last_bg_pid
- , (unsigned) G.last_exitcode
- , cnt
- , empty_trap_mask
- IF_HUSH_LOOPS(, G.depth_of_loop)
- );
-# undef NOMMU_HACK_FMT
- /* 1:hush 2:-$<pid>:<pid>:<exitcode>:<etc...> <vars...> <funcs...>
- * 3:-c 4:<cmd> 5:<arg0> <argN...> 6:NULL
- */
- cnt += 6;
- for (cur = G.top_var; cur; cur = cur->next) {
- if (!cur->flg_export || cur->flg_read_only)
- cnt += 2;
- }
-# if ENABLE_HUSH_FUNCTIONS
- for (funcp = G.top_func; funcp; funcp = funcp->next)
- cnt += 3;
+#if HAS_KEYWORDS
+# if ENABLE_HUSH_CASE
+ if (ctx->ctx_dsemicolon
+ && strcmp(word->data, "esac") != 0 /* not "... pattern) cmd;; esac" */
+ ) {
+ /* already done when ctx_dsemicolon was set to 1: */
+ /* ctx->ctx_res_w = RES_MATCH; */
+ ctx->ctx_dsemicolon = 0;
+ } else
# endif
- pp = g_argv;
- while (*pp++)
- cnt++;
- *to_free = argv = pp = xzalloc(sizeof(argv[0]) * cnt);
- *pp++ = (char *) G.argv0_for_re_execing;
- *pp++ = param_buf;
- for (cur = G.top_var; cur; cur = cur->next) {
- if (cur->varstr == hush_version_str)
- continue;
- if (cur->flg_read_only) {
- *pp++ = (char *) "-R";
- *pp++ = cur->varstr;
- } else if (!cur->flg_export) {
- *pp++ = (char *) "-V";
- *pp++ = cur->varstr;
+ if (!command->argv /* if it's the first word... */
+# if ENABLE_HUSH_LOOPS
+ && ctx->ctx_res_w != RES_FOR /* ...not after FOR or IN */
+ && ctx->ctx_res_w != RES_IN
+# endif
+# if ENABLE_HUSH_CASE
+ && ctx->ctx_res_w != RES_CASE
+# endif
+ ) {
+ debug_printf_parse("checking '%s' for reserved-ness\n", word->data);
+ if (reserved_word(word, ctx)) {
+ o_reset_to_empty_unquoted(word);
+ debug_printf_parse("done_word return %d\n",
+ (ctx->ctx_res_w == RES_SNTX));
+ return (ctx->ctx_res_w == RES_SNTX);
+ }
+# if ENABLE_HUSH_BASH_COMPAT
+ if (strcmp(word->data, "[[") == 0) {
+ command->cmd_type = CMD_SINGLEWORD_NOGLOB;
+ }
+ /* fall through */
+# endif
+ }
+#endif
+ if (command->group) {
+ /* "{ echo foo; } echo bar" - bad */
+ syntax_error_at(word->data);
+ debug_printf_parse("done_word return 1: syntax error, "
+ "groups and arglists don't mix\n");
+ return 1;
+ }
+ if (word->has_quoted_part
+ /* optimization: and if it's ("" or '') or ($v... or `cmd`...): */
+ && (word->data[0] == '\0' || word->data[0] == SPECIAL_VAR_SYMBOL)
+ /* (otherwise it's known to be not empty and is already safe) */
+ ) {
+ /* exclude "$@" - it can expand to no word despite "" */
+ char *p = word->data;
+ while (p[0] == SPECIAL_VAR_SYMBOL
+ && (p[1] & 0x7f) == '@'
+ && p[2] == SPECIAL_VAR_SYMBOL
+ ) {
+ p += 3;
+ }
+ if (p == word->data || p[0] != '\0') {
+ /* saw no "$@", or not only "$@" but some
+ * real text is there too */
+ /* insert "empty variable" reference, this makes
+ * e.g. "", $empty"" etc to not disappear */
+ o_addchr(word, SPECIAL_VAR_SYMBOL);
+ o_addchr(word, SPECIAL_VAR_SYMBOL);
+ }
}
+ command->argv = add_string_to_strings(command->argv, xstrdup(word->data));
+ debug_print_strings("word appended to argv", command->argv);
}
-# if ENABLE_HUSH_FUNCTIONS
- for (funcp = G.top_func; funcp; funcp = funcp->next) {
- *pp++ = (char *) "-F";
- *pp++ = funcp->name;
- *pp++ = funcp->body_as_string;
+
+#if ENABLE_HUSH_LOOPS
+ if (ctx->ctx_res_w == RES_FOR) {
+ if (word->has_quoted_part
+ || !is_well_formed_var_name(command->argv[0], '\0')
+ ) {
+ /* bash says just "not a valid identifier" */
+ syntax_error("not a valid identifier in for");
+ return 1;
+ }
+ /* Force FOR to have just one word (variable name) */
+ /* NB: basically, this makes hush see "for v in ..."
+ * syntax as if it is "for v; in ...". FOR and IN become
+ * two pipe structs in parse tree. */
+ done_pipe(ctx, PIPE_SEQ);
}
-# endif
- /* We can pass activated traps here. Say, -Tnn:trap_string
- *
- * However, POSIX says that subshells reset signals with traps
- * to SIG_DFL.
- * I tested bash-3.2 and it not only does that with true subshells
- * of the form ( list ), but with any forked children shells.
- * I set trap "echo W" WINCH; and then tried:
- *
- * { echo 1; sleep 20; echo 2; } &
- * while true; do echo 1; sleep 20; echo 2; break; done &
- * true | { echo 1; sleep 20; echo 2; } | cat
- *
- * In all these cases sending SIGWINCH to the child shell
- * did not run the trap. If I add trap "echo V" WINCH;
- * _inside_ group (just before echo 1), it works.
- *
- * I conclude it means we don't need to pass active traps here.
- * Even if we would use signal handlers instead of signal masking
- * in order to implement trap handling,
- * exec syscall below resets signals to SIG_DFL for us.
- */
- *pp++ = (char *) "-c";
- *pp++ = (char *) s;
- if (builtin_argv) {
- while (*++builtin_argv)
- *pp++ = *builtin_argv;
- *pp++ = (char *) "";
+#endif
+#if ENABLE_HUSH_CASE
+ /* Force CASE to have just one word */
+ if (ctx->ctx_res_w == RES_CASE) {
+ done_pipe(ctx, PIPE_SEQ);
}
- *pp++ = g_argv0;
- while (*g_argv)
- *pp++ = *g_argv++;
- /* *pp = NULL; - is already there */
- pp = environ;
+#endif
- do_exec:
- debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s);
- sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
- execve(bb_busybox_exec_path, argv, pp);
- /* Fallback. Useful for init=/bin/hush usage etc */
- if (argv[0][0] == '/')
- execve(argv[0], argv, pp);
- xfunc_error_retval = 127;
- bb_error_msg_and_die("can't re-execute the shell");
+ o_reset_to_empty_unquoted(word);
+
+ debug_printf_parse("done_word return 0\n");
+ return 0;
}
-#endif /* !BB_MMU */
-static void setup_heredoc(struct redir_struct *redir)
+/* Peek ahead in the input to find out if we have a "&n" construct,
+ * as in "2>&1", that represents duplicating a file descriptor.
+ * Return:
+ * REDIRFD_CLOSE if >&- "close fd" construct is seen,
+ * REDIRFD_SYNTAX_ERR if syntax error,
+ * REDIRFD_TO_FILE if no & was seen,
+ * or the number found.
+ */
+#if BB_MMU
+#define parse_redir_right_fd(as_string, input) \
+ parse_redir_right_fd(input)
+#endif
+static int parse_redir_right_fd(o_string *as_string, struct in_str *input)
{
- struct fd_pair pair;
- pid_t pid;
- int len, written;
- /* the _body_ of heredoc (misleading field name) */
- const char *heredoc = redir->rd_filename;
- char *expanded;
-#if !BB_MMU
- char **to_free;
-#endif
-
- expanded = NULL;
- if (!(redir->rd_dup & HEREDOC_QUOTED)) {
- expanded = expand_pseudo_dquoted(heredoc);
- if (expanded)
- heredoc = expanded;
- }
- len = strlen(heredoc);
+ int ch, d, ok;
- close(redir->rd_fd); /* often saves dup2+close in xmove_fd */
- xpiped_pair(pair);
- xmove_fd(pair.rd, redir->rd_fd);
+ ch = i_peek(input);
+ if (ch != '&')
+ return REDIRFD_TO_FILE;
- /* Try writing without forking. Newer kernels have
- * dynamically growing pipes. Must use non-blocking write! */
- ndelay_on(pair.wr);
- while (1) {
- written = write(pair.wr, heredoc, len);
- if (written <= 0)
- break;
- len -= written;
- if (len == 0) {
- close(pair.wr);
- free(expanded);
- return;
- }
- heredoc += written;
+ ch = i_getch(input); /* get the & */
+ nommu_addchr(as_string, ch);
+ ch = i_peek(input);
+ if (ch == '-') {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ return REDIRFD_CLOSE;
}
- ndelay_off(pair.wr);
-
- /* Okay, pipe buffer was not big enough */
- /* Note: we must not create a stray child (bastard? :)
- * for the unsuspecting parent process. Child creates a grandchild
- * and exits before parent execs the process which consumes heredoc
- * (that exec happens after we return from this function) */
-#if !BB_MMU
- to_free = NULL;
-#endif
- pid = xvfork();
- if (pid == 0) {
- /* child */
- disable_restore_tty_pgrp_on_exit();
- pid = BB_MMU ? xfork() : xvfork();
- if (pid != 0)
- _exit(0);
- /* grandchild */
- close(redir->rd_fd); /* read side of the pipe */
-#if BB_MMU
- full_write(pair.wr, heredoc, len); /* may loop or block */
- _exit(0);
-#else
- /* Delegate blocking writes to another process */
- xmove_fd(pair.wr, STDOUT_FILENO);
- re_execute_shell(&to_free, heredoc, NULL, NULL, NULL);
-#endif
+ d = 0;
+ ok = 0;
+ while (ch != EOF && isdigit(ch)) {
+ d = d*10 + (ch-'0');
+ ok = 1;
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ ch = i_peek(input);
}
- /* parent */
-#if ENABLE_HUSH_FAST
- G.count_SIGCHLD++;
-//bb_error_msg("[%d] fork in setup_heredoc: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
-#endif
- enable_restore_tty_pgrp_on_exit();
-#if !BB_MMU
- free(to_free);
-#endif
- close(pair.wr);
- free(expanded);
- wait(NULL); /* wait till child has died */
+ if (ok) return d;
+
+//TODO: this is the place to catch ">&file" bashism (redirect both fd 1 and 2)
+
+ bb_error_msg("ambiguous redirect");
+ return REDIRFD_SYNTAX_ERR;
}
-/* squirrel != NULL means we squirrel away copies of stdin, stdout,
- * and stderr if they are redirected. */
-static int setup_redirects(struct command *prog, int squirrel[])
+/* Return code is 0 normal, 1 if a syntax error is detected
+ */
+static int parse_redirect(struct parse_context *ctx,
+ int fd,
+ redir_type style,
+ struct in_str *input)
{
- int openfd, mode;
+ struct command *command = ctx->command;
struct redir_struct *redir;
+ struct redir_struct **redirp;
+ int dup_num;
- for (redir = prog->redirects; redir; redir = redir->next) {
- if (redir->rd_type == REDIRECT_HEREDOC2) {
- /* rd_fd<<HERE case */
- if (squirrel && redir->rd_fd < 3
- && squirrel[redir->rd_fd] < 0
- ) {
- squirrel[redir->rd_fd] = dup(redir->rd_fd);
- }
- /* for REDIRECT_HEREDOC2, rd_filename holds _contents_
- * of the heredoc */
- debug_printf_parse("set heredoc '%s'\n",
- redir->rd_filename);
- setup_heredoc(redir);
- continue;
+ dup_num = REDIRFD_TO_FILE;
+ if (style != REDIRECT_HEREDOC) {
+ /* Check for a '>&1' type redirect */
+ dup_num = parse_redir_right_fd(&ctx->as_string, input);
+ if (dup_num == REDIRFD_SYNTAX_ERR)
+ return 1;
+ } else {
+ int ch = i_peek(input);
+ dup_num = (ch == '-'); /* HEREDOC_SKIPTABS bit is 1 */
+ if (dup_num) { /* <<-... */
+ ch = i_getch(input);
+ nommu_addchr(&ctx->as_string, ch);
+ ch = i_peek(input);
}
+ }
- if (redir->rd_dup == REDIRFD_TO_FILE) {
- /* rd_fd<*>file case (<*> is <,>,>>,<>) */
- char *p;
- if (redir->rd_filename == NULL) {
- /* Something went wrong in the parse.
- * Pretend it didn't happen */
- bb_error_msg("bug in redirect parse");
- continue;
- }
- mode = redir_table[redir->rd_type].mode;
- p = expand_string_to_string(redir->rd_filename);
- openfd = open_or_warn(p, mode);
- free(p);
- if (openfd < 0) {
- /* this could get lost if stderr has been redirected, but
- * bash and ash both lose it as well (though zsh doesn't!) */
-//what the above comment tries to say?
- return 1;
- }
- } else {
- /* rd_fd<*>rd_dup or rd_fd<*>- cases */
- openfd = redir->rd_dup;
+ if (style == REDIRECT_OVERWRITE && dup_num == REDIRFD_TO_FILE) {
+ int ch = i_peek(input);
+ if (ch == '|') {
+ /* >|FILE redirect ("clobbering" >).
+ * Since we do not support "set -o noclobber" yet,
+ * >| and > are the same for now. Just eat |.
+ */
+ ch = i_getch(input);
+ nommu_addchr(&ctx->as_string, ch);
}
+ }
- if (openfd != redir->rd_fd) {
- if (squirrel && redir->rd_fd < 3
- && squirrel[redir->rd_fd] < 0
- ) {
- squirrel[redir->rd_fd] = dup(redir->rd_fd);
- }
- if (openfd == REDIRFD_CLOSE) {
- /* "n>-" means "close me" */
- close(redir->rd_fd);
- } else {
- xdup2(openfd, redir->rd_fd);
- if (redir->rd_dup == REDIRFD_TO_FILE)
- close(openfd);
- }
- }
+ /* Create a new redir_struct and append it to the linked list */
+ redirp = &command->redirects;
+ while ((redir = *redirp) != NULL) {
+ redirp = &(redir->next);
}
- return 0;
-}
+ *redirp = redir = xzalloc(sizeof(*redir));
+ /* redir->next = NULL; */
+ /* redir->rd_filename = NULL; */
+ redir->rd_type = style;
+ redir->rd_fd = (fd == -1) ? redir_table[style].default_fd : fd;
-static void restore_redirects(int squirrel[])
-{
- int i, fd;
- for (i = 0; i < 3; i++) {
- fd = squirrel[i];
- if (fd != -1) {
- /* We simply die on error */
- xmove_fd(fd, i);
- }
+ debug_printf_parse("redirect type %d %s\n", redir->rd_fd,
+ redir_table[style].descrip);
+
+ redir->rd_dup = dup_num;
+ if (style != REDIRECT_HEREDOC && dup_num != REDIRFD_TO_FILE) {
+ /* Erik had a check here that the file descriptor in question
+ * is legit; I postpone that to "run time"
+ * A "-" representation of "close me" shows up as a -3 here */
+ debug_printf_parse("duplicating redirect '%d>&%d'\n",
+ redir->rd_fd, redir->rd_dup);
+ } else {
+ /* Set ctx->pending_redirect, so we know what to do at the
+ * end of the next parsed word. */
+ ctx->pending_redirect = redir;
}
+ return 0;
}
+/* If a redirect is immediately preceded by a number, that number is
+ * supposed to tell which file descriptor to redirect. This routine
+ * looks for such preceding numbers. In an ideal world this routine
+ * needs to handle all the following classes of redirects...
+ * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
+ * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
+ * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
+ * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
+ *
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
+ * "2.7 Redirection
+ * ... If n is quoted, the number shall not be recognized as part of
+ * the redirection expression. For example:
+ * echo \2>a
+ * writes the character 2 into file a"
+ * We are getting it right by setting ->has_quoted_part on any \<char>
+ *
+ * A -1 return means no valid number was found,
+ * the caller should use the appropriate default for this redirection.
+ */
+static int redirect_opt_num(o_string *o)
+{
+ int num;
-static void free_pipe_list(struct pipe *head);
+ if (o->data == NULL)
+ return -1;
+ num = bb_strtou(o->data, NULL, 10);
+ if (errno || num < 0)
+ return -1;
+ o_reset_to_empty_unquoted(o);
+ return num;
+}
-/* Return code is the exit status of the pipe */
-static void free_pipe(struct pipe *pi)
+#if BB_MMU
+#define fetch_till_str(as_string, input, word, skip_tabs) \
+ fetch_till_str(input, word, skip_tabs)
+#endif
+static char *fetch_till_str(o_string *as_string,
+ struct in_str *input,
+ const char *word,
+ int heredoc_flags)
{
- char **p;
- struct command *command;
- struct redir_struct *r, *rnext;
- int a, i;
-
- if (pi->stopped_cmds > 0) /* why? */
- return;
- debug_printf_clean("run pipe: (pid %d)\n", getpid());
- for (i = 0; i < pi->num_cmds; i++) {
- command = &pi->cmds[i];
- debug_printf_clean(" command %d:\n", i);
- if (command->argv) {
- for (a = 0, p = command->argv; *p; a++, p++) {
- debug_printf_clean(" argv[%d] = %s\n", a, *p);
+ o_string heredoc = NULL_O_STRING;
+ int past_EOL = 0;
+ int prev = 0; /* not \ */
+ int ch;
+
+ goto jump_in;
+ while (1) {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ if (ch == '\n'
+ /* TODO: or EOF? (heredoc delimiter may end with <eof>, not only <eol>) */
+ && ((heredoc_flags & HEREDOC_QUOTED) || prev != '\\')
+ ) {
+ if (strcmp(heredoc.data + past_EOL, word) == 0) {
+ heredoc.data[past_EOL] = '\0';
+ debug_printf_parse("parsed heredoc '%s'\n", heredoc.data);
+ return heredoc.data;
}
- free_strings(command->argv);
- command->argv = NULL;
- }
- /* not "else if": on syntax error, we may have both! */
- if (command->group) {
- debug_printf_clean(" begin group (cmd_type:%d)\n",
- command->cmd_type);
- free_pipe_list(command->group);
- debug_printf_clean(" end group\n");
- command->group = NULL;
- }
- /* else is crucial here.
- * If group != NULL, child_func is meaningless */
-#if ENABLE_HUSH_FUNCTIONS
- else if (command->child_func) {
- debug_printf_exec("cmd %p releases child func at %p\n", command, command->child_func);
- command->child_func->parent_cmd = NULL;
+ do {
+ o_addchr(&heredoc, '\n');
+ prev = 0; /* not \ */
+ past_EOL = heredoc.length;
+ jump_in:
+ do {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ } while ((heredoc_flags & HEREDOC_SKIPTABS) && ch == '\t');
+ } while (ch == '\n');
}
-#endif
-#if !BB_MMU
- free(command->group_as_string);
- command->group_as_string = NULL;
-#endif
- for (r = command->redirects; r; r = rnext) {
- debug_printf_clean(" redirect %d%s",
- r->rd_fd, redir_table[r->rd_type].descrip);
- /* guard against the case >$FOO, where foo is unset or blank */
- if (r->rd_filename) {
- debug_printf_clean(" fname:'%s'\n", r->rd_filename);
- free(r->rd_filename);
- r->rd_filename = NULL;
- }
- debug_printf_clean(" rd_dup:%d\n", r->rd_dup);
- rnext = r->next;
- free(r);
+ if (ch == EOF) {
+ o_free_unsafe(&heredoc);
+ return NULL;
}
- command->redirects = NULL;
+ o_addchr(&heredoc, ch);
+ if (prev == '\\' && ch == '\\')
+ /* Correctly handle foo\\<eol> (not a line cont.) */
+ prev = 0; /* not \ */
+ else
+ prev = ch;
+ nommu_addchr(as_string, ch);
}
- free(pi->cmds); /* children are an array, they get freed all at once */
- pi->cmds = NULL;
-#if ENABLE_HUSH_JOB
- free(pi->cmdtext);
- pi->cmdtext = NULL;
-#endif
}
-static void free_pipe_list(struct pipe *head)
+/* Look at entire parse tree for not-yet-loaded REDIRECT_HEREDOCs
+ * and load them all. There should be exactly heredoc_cnt of them.
+ */
+static int fetch_heredocs(int heredoc_cnt, struct parse_context *ctx, struct in_str *input)
{
- struct pipe *pi, *next;
+ struct pipe *pi = ctx->list_head;
- for (pi = head; pi; pi = next) {
-#if HAS_KEYWORDS
- debug_printf_clean(" pipe reserved word %d\n", pi->res_word);
-#endif
- free_pipe(pi);
- debug_printf_clean("pipe followup code %d\n", pi->followup);
- next = pi->next;
- /*pi->next = NULL;*/
- free(pi);
+ while (pi && heredoc_cnt) {
+ int i;
+ struct command *cmd = pi->cmds;
+
+ debug_printf_parse("fetch_heredocs: num_cmds:%d cmd argv0:'%s'\n",
+ pi->num_cmds,
+ cmd->argv ? cmd->argv[0] : "NONE");
+ for (i = 0; i < pi->num_cmds; i++) {
+ struct redir_struct *redir = cmd->redirects;
+
+ debug_printf_parse("fetch_heredocs: %d cmd argv0:'%s'\n",
+ i, cmd->argv ? cmd->argv[0] : "NONE");
+ while (redir) {
+ if (redir->rd_type == REDIRECT_HEREDOC) {
+ char *p;
+
+ redir->rd_type = REDIRECT_HEREDOC2;
+ /* redir->rd_dup is (ab)used to indicate <<- */
+ p = fetch_till_str(&ctx->as_string, input,
+ redir->rd_filename, redir->rd_dup);
+ if (!p) {
+ syntax_error("unexpected EOF in here document");
+ return 1;
+ }
+ free(redir->rd_filename);
+ redir->rd_filename = p;
+ heredoc_cnt--;
+ }
+ redir = redir->next;
+ }
+ cmd++;
+ }
+ pi = pi->next;
}
+#if 0
+ /* Should be 0. If it isn't, it's a parse error */
+ if (heredoc_cnt)
+ bb_error_msg_and_die("heredoc BUG 2");
+#endif
+ return 0;
}
static struct pipe *parse_stream(char **pstring,
struct in_str *input,
int end_trigger);
-static void parse_and_run_string(const char *s);
-static char *find_in_path(const char *arg)
+#if !ENABLE_HUSH_FUNCTIONS
+#define parse_group(dest, ctx, input, ch) \
+ parse_group(ctx, input, ch)
+#endif
+static int parse_group(o_string *dest, struct parse_context *ctx,
+ struct in_str *input, int ch)
{
- char *ret = NULL;
- const char *PATH = get_local_var_value("PATH");
+ /* dest contains characters seen prior to ( or {.
+ * Typically it's empty, but for function defs,
+ * it contains function name (without '()'). */
+ struct pipe *pipe_list;
+ int endch;
+ struct command *command = ctx->command;
- if (!PATH)
- return NULL;
+ debug_printf_parse("parse_group entered\n");
+#if ENABLE_HUSH_FUNCTIONS
+ if (ch == '(' && !dest->has_quoted_part) {
+ if (dest->length)
+ if (done_word(dest, ctx))
+ return 1;
+ if (!command->argv)
+ goto skip; /* (... */
+ if (command->argv[1]) { /* word word ... (... */
+ syntax_error_unexpected_ch('(');
+ return 1;
+ }
+ /* it is "word(..." or "word (..." */
+ do
+ ch = i_getch(input);
+ while (ch == ' ' || ch == '\t');
+ if (ch != ')') {
+ syntax_error_unexpected_ch(ch);
+ return 1;
+ }
+ nommu_addchr(&ctx->as_string, ch);
+ do
+ ch = i_getch(input);
+ while (ch == ' ' || ch == '\t' || ch == '\n');
+ if (ch != '{') {
+ syntax_error_unexpected_ch(ch);
+ return 1;
+ }
+ nommu_addchr(&ctx->as_string, ch);
+ command->cmd_type = CMD_FUNCDEF;
+ goto skip;
+ }
+#endif
- while (1) {
- const char *end = strchrnul(PATH, ':');
- int sz = end - PATH; /* must be int! */
+#if 0 /* Prevented by caller */
+ if (command->argv /* word [word]{... */
+ || dest->length /* word{... */
+ || dest->has_quoted_part /* ""{... */
+ ) {
+ syntax_error(NULL);
+ debug_printf_parse("parse_group return 1: "
+ "syntax error, groups and arglists don't mix\n");
+ return 1;
+ }
+#endif
- free(ret);
- if (sz != 0) {
- ret = xasprintf("%.*s/%s", sz, PATH, arg);
- } else {
- /* We have xxx::yyyy in $PATH,
- * it means "use current dir" */
- ret = xstrdup(arg);
+#if ENABLE_HUSH_FUNCTIONS
+ skip:
+#endif
+ endch = '}';
+ if (ch == '(') {
+ endch = ')';
+ command->cmd_type = CMD_SUBSHELL;
+ } else {
+ /* bash does not allow "{echo...", requires whitespace */
+ ch = i_getch(input);
+ if (ch != ' ' && ch != '\t' && ch != '\n') {
+ syntax_error_unexpected_ch(ch);
+ return 1;
}
- if (access(ret, F_OK) == 0)
- break;
+ nommu_addchr(&ctx->as_string, ch);
+ }
- if (*end == '\0') {
- free(ret);
- return NULL;
+ {
+#if BB_MMU
+# define as_string NULL
+#else
+ char *as_string = NULL;
+#endif
+ pipe_list = parse_stream(&as_string, input, endch);
+#if !BB_MMU
+ if (as_string)
+ o_addstr(&ctx->as_string, as_string);
+#endif
+ /* empty ()/{} or parse error? */
+ if (!pipe_list || pipe_list == ERR_PTR) {
+ /* parse_stream already emitted error msg */
+ if (!BB_MMU)
+ free(as_string);
+ debug_printf_parse("parse_group return 1: "
+ "parse_stream returned %p\n", pipe_list);
+ return 1;
}
- PATH = end + 1;
+ command->group = pipe_list;
+#if !BB_MMU
+ as_string[strlen(as_string) - 1] = '\0'; /* plink ')' or '}' */
+ command->group_as_string = as_string;
+ debug_printf_parse("end of group, remembering as:'%s'\n",
+ command->group_as_string);
+#endif
+#undef as_string
}
-
- return ret;
+ debug_printf_parse("parse_group return 0\n");
+ return 0;
+ /* command remains "open", available for possible redirects */
}
-static const struct built_in_command* find_builtin_helper(const char *name,
- const struct built_in_command *x,
- const struct built_in_command *end)
+#if ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_DOLLAR_OPS
+/* Subroutines for copying $(...) and `...` things */
+static void add_till_backquote(o_string *dest, struct in_str *input);
+/* '...' */
+static void add_till_single_quote(o_string *dest, struct in_str *input)
{
- while (x != end) {
- if (strcmp(name, x->b_cmd) != 0) {
- x++;
- continue;
+ while (1) {
+ int ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('\'');
+ /*xfunc_die(); - redundant */
}
- debug_printf_exec("found builtin '%s'\n", name);
- return x;
+ if (ch == '\'')
+ return;
+ o_addchr(dest, ch);
}
- return NULL;
}
-static const struct built_in_command* find_builtin1(const char *name)
-{
- return find_builtin_helper(name, bltins1, &bltins1[ARRAY_SIZE(bltins1)]);
-}
-static const struct built_in_command* find_builtin(const char *name)
-{
- const struct built_in_command *x = find_builtin1(name);
- if (x)
- return x;
- return find_builtin_helper(name, bltins2, &bltins2[ARRAY_SIZE(bltins2)]);
-}
-
-#if ENABLE_HUSH_FUNCTIONS
-static struct function **find_function_slot(const char *name)
+/* "...\"...`..`...." - do we need to handle "...$(..)..." too? */
+static void add_till_double_quote(o_string *dest, struct in_str *input)
{
- struct function **funcpp = &G.top_func;
- while (*funcpp) {
- if (strcmp(name, (*funcpp)->name) == 0) {
- break;
+ while (1) {
+ int ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('"');
+ /*xfunc_die(); - redundant */
}
- funcpp = &(*funcpp)->next;
+ if (ch == '"')
+ return;
+ if (ch == '\\') { /* \x. Copy both chars. */
+ o_addchr(dest, ch);
+ ch = i_getch(input);
+ }
+ o_addchr(dest, ch);
+ if (ch == '`') {
+ add_till_backquote(dest, input);
+ o_addchr(dest, ch);
+ continue;
+ }
+ //if (ch == '$') ...
}
- return funcpp;
-}
-
-static const struct function *find_function(const char *name)
-{
- const struct function *funcp = *find_function_slot(name);
- if (funcp)
- debug_printf_exec("found function '%s'\n", name);
- return funcp;
}
-
-/* Note: takes ownership on name ptr */
-static struct function *new_function(char *name)
+/* Process `cmd` - copy contents until "`" is seen. Complicated by
+ * \` quoting.
+ * "Within the backquoted style of command substitution, backslash
+ * shall retain its literal meaning, except when followed by: '$', '`', or '\'.
+ * The search for the matching backquote shall be satisfied by the first
+ * backquote found without a preceding backslash; during this search,
+ * if a non-escaped backquote is encountered within a shell comment,
+ * a here-document, an embedded command substitution of the $(command)
+ * form, or a quoted string, undefined results occur. A single-quoted
+ * or double-quoted string that begins, but does not end, within the
+ * "`...`" sequence produces undefined results."
+ * Example Output
+ * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST
+ */
+static void add_till_backquote(o_string *dest, struct in_str *input)
{
- struct function **funcpp = find_function_slot(name);
- struct function *funcp = *funcpp;
-
- if (funcp != NULL) {
- struct command *cmd = funcp->parent_cmd;
- debug_printf_exec("func %p parent_cmd %p\n", funcp, cmd);
- if (!cmd) {
- debug_printf_exec("freeing & replacing function '%s'\n", funcp->name);
- free(funcp->name);
- /* Note: if !funcp->body, do not free body_as_string!
- * This is a special case of "-F name body" function:
- * body_as_string was not malloced! */
- if (funcp->body) {
- free_pipe_list(funcp->body);
-# if !BB_MMU
- free(funcp->body_as_string);
-# endif
+ while (1) {
+ int ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('`');
+ /*xfunc_die(); - redundant */
+ }
+ if (ch == '`')
+ return;
+ if (ch == '\\') {
+ /* \x. Copy both chars unless it is \` */
+ int ch2 = i_getch(input);
+ if (ch2 == EOF) {
+ syntax_error_unterm_ch('`');
+ /*xfunc_die(); - redundant */
}
- } else {
- debug_printf_exec("reinserting in tree & replacing function '%s'\n", funcp->name);
- cmd->argv[0] = funcp->name;
- cmd->group = funcp->body;
-# if !BB_MMU
- cmd->group_as_string = funcp->body_as_string;
-# endif
+ if (ch2 != '`' && ch2 != '$' && ch2 != '\\')
+ o_addchr(dest, ch);
+ ch = ch2;
}
- } else {
- debug_printf_exec("remembering new function '%s'\n", name);
- funcp = *funcpp = xzalloc(sizeof(*funcp));
- /*funcp->next = NULL;*/
+ o_addchr(dest, ch);
}
-
- funcp->name = name;
- return funcp;
}
-
-static void unset_func(const char *name)
+/* Process $(cmd) - copy contents until ")" is seen. Complicated by
+ * quoting and nested ()s.
+ * "With the $(command) style of command substitution, all characters
+ * following the open parenthesis to the matching closing parenthesis
+ * constitute the command. Any valid shell script can be used for command,
+ * except a script consisting solely of redirections which produces
+ * unspecified results."
+ * Example Output
+ * echo $(echo '(TEST)' BEST) (TEST) BEST
+ * echo $(echo 'TEST)' BEST) TEST) BEST
+ * echo $(echo \(\(TEST\) BEST) ((TEST) BEST
+ *
+ * Also adapted to eat ${var%...} and $((...)) constructs, since ... part
+ * can contain arbitrary constructs, just like $(cmd).
+ * In bash compat mode, it needs to also be able to stop on ':' or '/'
+ * for ${var:N[:M]} and ${var/P[/R]} parsing.
+ */
+#define DOUBLE_CLOSE_CHAR_FLAG 0x80
+static int add_till_closing_bracket(o_string *dest, struct in_str *input, unsigned end_ch)
{
- struct function **funcpp = find_function_slot(name);
- struct function *funcp = *funcpp;
-
- if (funcp != NULL) {
- debug_printf_exec("freeing function '%s'\n", funcp->name);
- *funcpp = funcp->next;
- /* funcp is unlinked now, deleting it.
- * Note: if !funcp->body, the function was created by
- * "-F name body", do not free ->body_as_string
- * and ->name as they were not malloced. */
- if (funcp->body) {
- free_pipe_list(funcp->body);
- free(funcp->name);
-# if !BB_MMU
- free(funcp->body_as_string);
+ int ch;
+ char dbl = end_ch & DOUBLE_CLOSE_CHAR_FLAG;
+# if ENABLE_HUSH_BASH_COMPAT
+ char end_char2 = end_ch >> 8;
# endif
+ end_ch &= (DOUBLE_CLOSE_CHAR_FLAG - 1);
+
+ while (1) {
+ ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch(end_ch);
+ /*xfunc_die(); - redundant */
+ }
+ if (ch == end_ch IF_HUSH_BASH_COMPAT( || ch == end_char2)) {
+ if (!dbl)
+ break;
+ /* we look for closing )) of $((EXPR)) */
+ if (i_peek(input) == end_ch) {
+ i_getch(input); /* eat second ')' */
+ break;
+ }
+ }
+ o_addchr(dest, ch);
+ if (ch == '(' || ch == '{') {
+ ch = (ch == '(' ? ')' : '}');
+ add_till_closing_bracket(dest, input, ch);
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '\'') {
+ add_till_single_quote(dest, input);
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '"') {
+ add_till_double_quote(dest, input);
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '`') {
+ add_till_backquote(dest, input);
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '\\') {
+ /* \x. Copy verbatim. Important for \(, \) */
+ ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch(')');
+ /*xfunc_die(); - redundant */
+ }
+ o_addchr(dest, ch);
+ continue;
}
- free(funcp);
}
+ return ch;
}
+#endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_DOLLAR_OPS */
-# if BB_MMU
-#define exec_function(to_free, funcp, argv) \
- exec_function(funcp, argv)
-# endif
-static void exec_function(char ***to_free,
- const struct function *funcp,
- char **argv) NORETURN;
-static void exec_function(char ***to_free,
- const struct function *funcp,
- char **argv)
-{
-# if BB_MMU
- int n = 1;
-
- argv[0] = G.global_argv[0];
- G.global_argv = argv;
- while (*++argv)
- n++;
- G.global_argc = n;
- /* On MMU, funcp->body is always non-NULL */
- n = run_list(funcp->body);
- fflush_all();
- _exit(n);
-# else
- re_execute_shell(to_free,
- funcp->body_as_string,
- G.global_argv[0],
- argv + 1,
- NULL);
-# endif
-}
-
-static int run_function(const struct function *funcp, char **argv)
+/* Return code: 0 for OK, 1 for syntax error */
+#if BB_MMU
+#define parse_dollar(as_string, dest, input) \
+ parse_dollar(dest, input)
+#define as_string NULL
+#endif
+static int parse_dollar(o_string *as_string,
+ o_string *dest,
+ struct in_str *input)
{
- int rc;
- save_arg_t sv;
- smallint sv_flg;
-
- save_and_replace_G_args(&sv, argv);
-
- /* "we are in function, ok to use return" */
- sv_flg = G.flag_return_in_progress;
- G.flag_return_in_progress = -1;
-# if ENABLE_HUSH_LOCAL
- G.func_nest_level++;
-# endif
+ int ch = i_peek(input); /* first character after the $ */
+ unsigned char quote_mask = (dest->o_expflags & EXP_FLAG_ESC_GLOB_CHARS) ? 0x80 : 0;
- /* On MMU, funcp->body is always non-NULL */
-# if !BB_MMU
- if (!funcp->body) {
- /* Function defined by -F */
- parse_and_run_string(funcp->body_as_string);
- rc = G.last_exitcode;
- } else
-# endif
- {
- rc = run_list(funcp->body);
- }
+ debug_printf_parse("parse_dollar entered: ch='%c'\n", ch);
+ if (isalpha(ch)) {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ make_var:
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ while (1) {
+ debug_printf_parse(": '%c'\n", ch);
+ o_addchr(dest, ch | quote_mask);
+ quote_mask = 0;
+ ch = i_peek(input);
+ if (!isalnum(ch) && ch != '_')
+ break;
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ } else if (isdigit(ch)) {
+ make_one_char_var:
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ debug_printf_parse(": '%c'\n", ch);
+ o_addchr(dest, ch | quote_mask);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ } else switch (ch) {
+ case '$': /* pid */
+ case '!': /* last bg pid */
+ case '?': /* last exit code */
+ case '#': /* number of args */
+ case '*': /* args */
+ case '@': /* args */
+ goto make_one_char_var;
+ case '{': {
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
-# if ENABLE_HUSH_LOCAL
- {
- struct variable *var;
- struct variable **var_pp;
+ ch = i_getch(input); /* eat '{' */
+ nommu_addchr(as_string, ch);
- var_pp = &G.top_var;
- while ((var = *var_pp) != NULL) {
- if (var->func_nest_level < G.func_nest_level) {
- var_pp = &var->next;
- continue;
- }
- /* Unexport */
- if (var->flg_export)
- bb_unsetenv(var->varstr);
- /* Remove from global list */
- *var_pp = var->next;
- /* Free */
- if (!var->max_len)
- free(var->varstr);
- free(var);
+ ch = i_getch(input); /* first char after '{' */
+ nommu_addchr(as_string, ch);
+ /* It should be ${?}, or ${#var},
+ * or even ${?+subst} - operator acting on a special variable,
+ * or the beginning of variable name.
+ */
+ if (!strchr(_SPECIAL_VARS_STR, ch) && !isalnum(ch)) { /* not one of those */
+ bad_dollar_syntax:
+ syntax_error_unterm_str("${name}");
+ debug_printf_parse("parse_dollar return 1: unterminated ${name}\n");
+ return 1;
}
- G.func_nest_level--;
- }
-# endif
- G.flag_return_in_progress = sv_flg;
+ ch |= quote_mask;
- restore_G_args(&sv, argv);
+ /* It's possible to just call add_till_closing_bracket() at this point.
+ * However, this regresses some of our testsuite cases
+ * which check invalid constructs like ${%}.
+ * Oh well... let's check that the var name part is fine... */
- return rc;
-}
-#endif /* ENABLE_HUSH_FUNCTIONS */
+ while (1) {
+ unsigned pos;
+ o_addchr(dest, ch);
+ debug_printf_parse(": '%c'\n", ch);
-#if BB_MMU
-#define exec_builtin(to_free, x, argv) \
- exec_builtin(x, argv)
-#else
-#define exec_builtin(to_free, x, argv) \
- exec_builtin(to_free, argv)
-#endif
-static void exec_builtin(char ***to_free,
- const struct built_in_command *x,
- char **argv) NORETURN;
-static void exec_builtin(char ***to_free,
- const struct built_in_command *x,
- char **argv)
-{
-#if BB_MMU
- int rcode = x->b_function(argv);
- fflush_all();
- _exit(rcode);
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ if (ch == '}')
+ break;
+
+ if (!isalnum(ch) && ch != '_') {
+ unsigned end_ch;
+ unsigned char last_ch;
+ /* handle parameter expansions
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02
+ */
+ if (!strchr(VAR_SUBST_OPS, ch)) /* ${var<bad_char>... */
+ goto bad_dollar_syntax;
+
+ /* Eat everything until closing '}' (or ':') */
+ end_ch = '}';
+ if (ENABLE_HUSH_BASH_COMPAT
+ && ch == ':'
+ && !strchr(MINUS_PLUS_EQUAL_QUESTION, i_peek(input))
+ ) {
+ /* It's ${var:N[:M]} thing */
+ end_ch = '}' * 0x100 + ':';
+ }
+ if (ENABLE_HUSH_BASH_COMPAT
+ && ch == '/'
+ ) {
+ /* It's ${var/[/]pattern[/repl]} thing */
+ if (i_peek(input) == '/') { /* ${var//pattern[/repl]}? */
+ i_getch(input);
+ nommu_addchr(as_string, '/');
+ ch = '\\';
+ }
+ end_ch = '}' * 0x100 + '/';
+ }
+ o_addchr(dest, ch);
+ again:
+ if (!BB_MMU)
+ pos = dest->length;
+#if ENABLE_HUSH_DOLLAR_OPS
+ last_ch = add_till_closing_bracket(dest, input, end_ch);
#else
- /* On NOMMU, we must never block!
- * Example: { sleep 99 | read line; } & echo Ok
- */
- re_execute_shell(to_free,
- argv[0],
- G.global_argv[0],
- G.global_argv + 1,
- argv);
+#error Simple code to only allow ${var} is not implemented
#endif
-}
+ if (as_string) {
+ o_addstr(as_string, dest->data + pos);
+ o_addchr(as_string, last_ch);
+ }
+ if (ENABLE_HUSH_BASH_COMPAT && (end_ch & 0xff00)) {
+ /* close the first block: */
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ /* while parsing N from ${var:N[:M]}
+ * or pattern from ${var/[/]pattern[/repl]} */
+ if ((end_ch & 0xff) == last_ch) {
+ /* got ':' or '/'- parse the rest */
+ end_ch = '}';
+ goto again;
+ }
+ /* got '}' */
+ if (end_ch == '}' * 0x100 + ':') {
+ /* it's ${var:N} - emulate :999999999 */
+ o_addstr(dest, "999999999");
+ } /* else: it's ${var/[/]pattern} */
+ }
+ break;
+ }
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ break;
+ }
+#if ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_TICK
+ case '(': {
+ unsigned pos;
-static void execvp_or_die(char **argv) NORETURN;
-static void execvp_or_die(char **argv)
-{
- debug_printf_exec("execing '%s'\n", argv[0]);
- sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
- execvp(argv[0], argv);
- bb_perror_msg("can't execute '%s'", argv[0]);
- _exit(127); /* bash compat */
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+# if ENABLE_SH_MATH_SUPPORT
+ if (i_peek(input) == '(') {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, /*quote_mask |*/ '+');
+ if (!BB_MMU)
+ pos = dest->length;
+ add_till_closing_bracket(dest, input, ')' | DOUBLE_CLOSE_CHAR_FLAG);
+ if (as_string) {
+ o_addstr(as_string, dest->data + pos);
+ o_addchr(as_string, ')');
+ o_addchr(as_string, ')');
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ break;
+ }
+# endif
+# if ENABLE_HUSH_TICK
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, quote_mask | '`');
+ if (!BB_MMU)
+ pos = dest->length;
+ add_till_closing_bracket(dest, input, ')');
+ if (as_string) {
+ o_addstr(as_string, dest->data + pos);
+ o_addchr(as_string, ')');
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+# endif
+ break;
+ }
+#endif
+ case '_':
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ ch = i_peek(input);
+ if (isalnum(ch)) { /* it's $_name or $_123 */
+ ch = '_';
+ goto make_var;
+ }
+ /* else: it's $_ */
+ /* TODO: $_ and $-: */
+ /* $_ Shell or shell script name; or last argument of last command
+ * (if last command wasn't a pipe; if it was, bash sets $_ to "");
+ * but in command's env, set to full pathname used to invoke it */
+ /* $- Option flags set by set builtin or shell options (-i etc) */
+ default:
+ o_addQchr(dest, '$');
+ }
+ debug_printf_parse("parse_dollar return 0\n");
+ return 0;
+#undef as_string
}
-static void dump_cmd_in_x_mode(char **argv)
+#if BB_MMU
+#define parse_stream_dquoted(as_string, dest, input, dquote_end) \
+ parse_stream_dquoted(dest, input, dquote_end)
+#define as_string NULL
+#endif
+static int parse_stream_dquoted(o_string *as_string,
+ o_string *dest,
+ struct in_str *input,
+ int dquote_end)
{
- if (G.x_mode && argv) {
- /* We want to output the line in one write op */
- char *buf, *p;
- int len;
- int n;
+ int ch;
+ int next;
- len = 3;
- n = 0;
- while (argv[n])
- len += strlen(argv[n++]) + 1;
- buf = xmalloc(len);
- buf[0] = '+';
- p = buf + 1;
- n = 0;
- while (argv[n])
- p += sprintf(p, " %s", argv[n++]);
- *p++ = '\n';
- *p = '\0';
- fputs(buf, stderr);
- free(buf);
+ again:
+ ch = i_getch(input);
+ if (ch != EOF)
+ nommu_addchr(as_string, ch);
+ if (ch == dquote_end) { /* may be only '"' or EOF */
+ if (dest->o_assignment == NOT_ASSIGNMENT)
+ dest->o_expflags ^= EXP_FLAG_ESC_GLOB_CHARS;
+ debug_printf_parse("parse_stream_dquoted return 0\n");
+ return 0;
}
-}
-
-#if BB_MMU
-#define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \
- pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
-#define pseudo_exec(nommu_save, command, argv_expanded) \
- pseudo_exec(command, argv_expanded)
-#endif
-
-/* Called after [v]fork() in run_pipe, or from builtin_exec.
- * Never returns.
- * Don't exit() here. If you don't exec, use _exit instead.
- * The at_exit handlers apparently confuse the calling process,
- * in particular stdin handling. Not sure why? -- because of vfork! (vda) */
-static void pseudo_exec_argv(nommu_save_t *nommu_save,
- char **argv, int assignment_cnt,
- char **argv_expanded) NORETURN;
-static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
- char **argv, int assignment_cnt,
- char **argv_expanded)
-{
- char **new_env;
-
- new_env = expand_assignments(argv, assignment_cnt);
- dump_cmd_in_x_mode(new_env);
-
- if (!argv[assignment_cnt]) {
- /* Case when we are here: ... | var=val | ...
- * (note that we do not exit early, i.e., do not optimize out
- * expand_assignments(): think about ... | var=`sleep 1` | ...
- */
- free_strings(new_env);
- _exit(EXIT_SUCCESS);
+ /* note: can't move it above ch == dquote_end check! */
+ if (ch == EOF) {
+ syntax_error_unterm_ch('"');
+ /*xfunc_die(); - redundant */
}
-
-#if BB_MMU
- set_vars_and_save_old(new_env);
- free(new_env); /* optional */
- /* we can also destroy set_vars_and_save_old's return value,
- * to save memory */
-#else
- nommu_save->new_env = new_env;
- nommu_save->old_vars = set_vars_and_save_old(new_env);
-#endif
-
- if (argv_expanded) {
- argv = argv_expanded;
- } else {
- argv = expand_strvec_to_strvec(argv + assignment_cnt);
-#if !BB_MMU
- nommu_save->argv = argv;
-#endif
+ next = '\0';
+ if (ch != '\n') {
+ next = i_peek(input);
}
- dump_cmd_in_x_mode(argv);
-
-#if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
- if (strchr(argv[0], '/') != NULL)
- goto skip;
-#endif
-
- /* Check if the command matches any of the builtins.
- * Depending on context, this might be redundant. But it's
- * easier to waste a few CPU cycles than it is to figure out
- * if this is one of those cases.
- */
- {
- /* On NOMMU, it is more expensive to re-execute shell
- * just in order to run echo or test builtin.
- * It's better to skip it here and run corresponding
- * non-builtin later. */
- const struct built_in_command *x;
- x = BB_MMU ? find_builtin(argv[0]) : find_builtin1(argv[0]);
- if (x) {
- exec_builtin(&nommu_save->argv_from_re_execing, x, argv);
+ debug_printf_parse("\" ch=%c (%d) escape=%d\n",
+ ch, ch, !!(dest->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ if (ch == '\\') {
+ if (next == EOF) {
+ syntax_error("\\<eof>");
+ xfunc_die();
}
- }
-#if ENABLE_HUSH_FUNCTIONS
- /* Check if the command matches any functions */
- {
- const struct function *funcp = find_function(argv[0]);
- if (funcp) {
- exec_function(&nommu_save->argv_from_re_execing, funcp, argv);
+ /* bash:
+ * "The backslash retains its special meaning [in "..."]
+ * only when followed by one of the following characters:
+ * $, `, ", \, or <newline>. A double quote may be quoted
+ * within double quotes by preceding it with a backslash."
+ * NB: in (unquoted) heredoc, above does not apply to ".
+ */
+ if (next == dquote_end || strchr("$`\\\n", next) != NULL) {
+ ch = i_getch(input);
+ if (ch != '\n') {
+ o_addqchr(dest, ch);
+ nommu_addchr(as_string, ch);
+ }
+ } else {
+ o_addqchr(dest, '\\');
+ nommu_addchr(as_string, '\\');
}
+ goto again;
}
-#endif
-
-#if ENABLE_FEATURE_SH_STANDALONE
- /* Check if the command matches any busybox applets */
- {
- int a = find_applet_by_name(argv[0]);
- if (a >= 0) {
-# if BB_MMU /* see above why on NOMMU it is not allowed */
- if (APPLET_IS_NOEXEC(a)) {
- debug_printf_exec("running applet '%s'\n", argv[0]);
- run_applet_no_and_exit(a, argv);
- }
-# endif
- /* Re-exec ourselves */
- debug_printf_exec("re-execing applet '%s'\n", argv[0]);
- sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
- execv(bb_busybox_exec_path, argv);
- /* If they called chroot or otherwise made the binary no longer
- * executable, fall through */
+ if (ch == '$') {
+ if (parse_dollar(as_string, dest, input) != 0) {
+ debug_printf_parse("parse_stream_dquoted return 1: "
+ "parse_dollar returned non-0\n");
+ return 1;
}
+ goto again;
}
-#endif
-
-#if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
- skip:
-#endif
- execvp_or_die(argv);
-}
-
-/* Called after [v]fork() in run_pipe
- */
-static void pseudo_exec(nommu_save_t *nommu_save,
- struct command *command,
- char **argv_expanded) NORETURN;
-static void pseudo_exec(nommu_save_t *nommu_save,
- struct command *command,
- char **argv_expanded)
-{
- if (command->argv) {
- pseudo_exec_argv(nommu_save, command->argv,
- command->assignment_cnt, argv_expanded);
+#if ENABLE_HUSH_TICK
+ if (ch == '`') {
+ //unsigned pos = dest->length;
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, 0x80 | '`');
+ add_till_backquote(dest, input);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
+ goto again;
}
-
- if (command->group) {
- /* Cases when we are here:
- * ( list )
- * { list } &
- * ... | ( list ) | ...
- * ... | { list } | ...
- */
-#if BB_MMU
- int rcode;
- debug_printf_exec("pseudo_exec: run_list\n");
- reset_traps_to_defaults();
- rcode = run_list(command->group);
- /* OK to leak memory by not calling free_pipe_list,
- * since this process is about to exit */
- _exit(rcode);
-#else
- re_execute_shell(&nommu_save->argv_from_re_execing,
- command->group_as_string,
- G.global_argv[0],
- G.global_argv + 1,
- NULL);
#endif
+ o_addQchr(dest, ch);
+ if (ch == '='
+ && (dest->o_assignment == MAYBE_ASSIGNMENT
+ || dest->o_assignment == WORD_IS_KEYWORD)
+ && is_well_formed_var_name(dest->data, '=')
+ ) {
+ dest->o_assignment = DEFINITELY_ASSIGNMENT;
}
-
- /* Case when we are here: ... | >file */
- debug_printf_exec("pseudo_exec'ed null command\n");
- _exit(EXIT_SUCCESS);
+ goto again;
+#undef as_string
}
-#if ENABLE_HUSH_JOB
-static const char *get_cmdtext(struct pipe *pi)
+/*
+ * Scan input until EOF or end_trigger char.
+ * Return a list of pipes to execute, or NULL on EOF
+ * or if end_trigger character is met.
+ * On syntax error, exit is shell is not interactive,
+ * reset parsing machinery and start parsing anew,
+ * or return ERR_PTR.
+ */
+static struct pipe *parse_stream(char **pstring,
+ struct in_str *input,
+ int end_trigger)
{
- char **argv;
- char *p;
- int len;
+ struct parse_context ctx;
+ o_string dest = NULL_O_STRING;
+ int is_in_dquote;
+ int heredoc_cnt;
- /* This is subtle. ->cmdtext is created only on first backgrounding.
- * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...)
- * On subsequent bg argv is trashed, but we won't use it */
- if (pi->cmdtext)
- return pi->cmdtext;
- argv = pi->cmds[0].argv;
- if (!argv || !argv[0]) {
- pi->cmdtext = xzalloc(1);
- return pi->cmdtext;
- }
+ /* Double-quote state is handled in the state variable is_in_dquote.
+ * A single-quote triggers a bypass of the main loop until its mate is
+ * found. When recursing, quote state is passed in via dest->o_expflags.
+ */
+ debug_printf_parse("parse_stream entered, end_trigger='%c'\n",
+ end_trigger ? end_trigger : 'X');
+ debug_enter();
- len = 0;
- do {
- len += strlen(*argv) + 1;
- } while (*++argv);
- p = xmalloc(len);
- pi->cmdtext = p;
- argv = pi->cmds[0].argv;
- do {
- len = strlen(*argv);
- memcpy(p, *argv, len);
- p += len;
- *p++ = ' ';
- } while (*++argv);
- p[-1] = '\0';
- return pi->cmdtext;
-}
-
-static void insert_bg_job(struct pipe *pi)
-{
- struct pipe *job, **jobp;
- int i;
-
- /* Linear search for the ID of the job to use */
- pi->jobid = 1;
- for (job = G.job_list; job; job = job->next)
- if (job->jobid >= pi->jobid)
- pi->jobid = job->jobid + 1;
-
- /* Add job to the list of running jobs */
- jobp = &G.job_list;
- while ((job = *jobp) != NULL)
- jobp = &job->next;
- job = *jobp = xmalloc(sizeof(*job));
-
- *job = *pi; /* physical copy */
- job->next = NULL;
- job->cmds = xzalloc(sizeof(pi->cmds[0]) * pi->num_cmds);
- /* Cannot copy entire pi->cmds[] vector! This causes double frees */
- for (i = 0; i < pi->num_cmds; i++) {
- job->cmds[i].pid = pi->cmds[i].pid;
- /* all other fields are not used and stay zero */
- }
- job->cmdtext = xstrdup(get_cmdtext(pi));
-
- if (G_interactive_fd)
- printf("[%d] %d %s\n", job->jobid, job->cmds[0].pid, job->cmdtext);
- /* Last command's pid goes to $! */
- G.last_bg_pid = job->cmds[job->num_cmds - 1].pid;
- G.last_jobid = job->jobid;
-}
+ /* If very first arg is "" or '', dest.data may end up NULL.
+ * Preventing this: */
+ o_addchr(&dest, '\0');
+ dest.length = 0;
-static void remove_bg_job(struct pipe *pi)
-{
- struct pipe *prev_pipe;
+ /* We used to separate words on $IFS here. This was wrong.
+ * $IFS is used only for word splitting when $var is expanded,
+ * here we should use blank chars as separators, not $iFS
+ */
+ reset:
+#if ENABLE_HUSH_INTERACTIVE
+ input->promptmode = 0; /* PS1 */
+#endif
+ /* dest.o_assignment = MAYBE_ASSIGNMENT; - already is */
+ initialize_context(&ctx);
+ is_in_dquote = 0;
+ heredoc_cnt = 0;
+ while (1) {
+ const char *is_blank;
+ const char *is_special;
+ int ch;
+ int next;
+ int redir_fd;
+ redir_type redir_style;
- if (pi == G.job_list) {
- G.job_list = pi->next;
- } else {
- prev_pipe = G.job_list;
- while (prev_pipe->next != pi)
- prev_pipe = prev_pipe->next;
- prev_pipe->next = pi->next;
- }
- if (G.job_list)
- G.last_jobid = G.job_list->jobid;
- else
- G.last_jobid = 0;
-}
+ if (is_in_dquote) {
+ /* dest.has_quoted_part = 1; - already is (see below) */
+ if (parse_stream_dquoted(&ctx.as_string, &dest, input, '"')) {
+ goto parse_error;
+ }
+ /* We reached closing '"' */
+ is_in_dquote = 0;
+ }
+ ch = i_getch(input);
+ debug_printf_parse(": ch=%c (%d) escape=%d\n",
+ ch, ch, !!(dest.o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ if (ch == EOF) {
+ struct pipe *pi;
-/* Remove a backgrounded job */
-static void delete_finished_bg_job(struct pipe *pi)
-{
- remove_bg_job(pi);
- pi->stopped_cmds = 0;
- free_pipe(pi);
- free(pi);
-}
-#endif /* JOB */
+ if (heredoc_cnt) {
+ syntax_error_unterm_str("here document");
+ goto parse_error;
+ }
+ /* end_trigger == '}' case errors out earlier,
+ * checking only ')' */
+ if (end_trigger == ')') {
+ syntax_error_unterm_ch('('); /* exits */
+ /* goto parse_error; */
+ }
-/* Check to see if any processes have exited -- if they
- * have, figure out why and see if a job has completed */
-static int checkjobs(struct pipe* fg_pipe)
-{
- int attributes;
- int status;
-#if ENABLE_HUSH_JOB
- struct pipe *pi;
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
+ }
+ o_free(&dest);
+ done_pipe(&ctx, PIPE_SEQ);
+ pi = ctx.list_head;
+ /* If we got nothing... */
+ /* (this makes bare "&" cmd a no-op.
+ * bash says: "syntax error near unexpected token '&'") */
+ if (pi->num_cmds == 0
+ IF_HAS_KEYWORDS( && pi->res_word == RES_NONE)
+ ) {
+ free_pipe_list(pi);
+ pi = NULL;
+ }
+#if !BB_MMU
+ debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
+ if (pstring)
+ *pstring = ctx.as_string.data;
+ else
+ o_free_unsafe(&ctx.as_string);
#endif
- pid_t childpid;
- int rcode = 0;
-
- debug_printf_jobs("checkjobs %p\n", fg_pipe);
+ debug_leave();
+ debug_printf_parse("parse_stream return %p\n", pi);
+ return pi;
+ }
+ nommu_addchr(&ctx.as_string, ch);
- attributes = WUNTRACED;
- if (fg_pipe == NULL)
- attributes |= WNOHANG;
+ next = '\0';
+ if (ch != '\n')
+ next = i_peek(input);
- errno = 0;
-#if ENABLE_HUSH_FAST
- if (G.handled_SIGCHLD == G.count_SIGCHLD) {
-//bb_error_msg("[%d] checkjobs: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d children?:%d fg_pipe:%p",
-//getpid(), G.count_SIGCHLD, G.handled_SIGCHLD, G.we_have_children, fg_pipe);
- /* There was neither fork nor SIGCHLD since last waitpid */
- /* Avoid doing waitpid syscall if possible */
- if (!G.we_have_children) {
- errno = ECHILD;
- return -1;
- }
- if (fg_pipe == NULL) { /* is WNOHANG set? */
- /* We have children, but they did not exit
- * or stop yet (we saw no SIGCHLD) */
- return 0;
+ is_special = "{}<>;&|()#'" /* special outside of "str" */
+ "\\$\"" IF_HUSH_TICK("`"); /* always special */
+ /* Are { and } special here? */
+ if (ctx.command->argv /* word [word]{... - non-special */
+ || dest.length /* word{... - non-special */
+ || dest.has_quoted_part /* ""{... - non-special */
+ || (next != ';' /* }; - special */
+ && next != ')' /* }) - special */
+ && next != '&' /* }& and }&& ... - special */
+ && next != '|' /* }|| ... - special */
+ && !strchr(defifs, next) /* {word - non-special */
+ )
+ ) {
+ /* They are not special, skip "{}" */
+ is_special += 2;
}
- /* else: !WNOHANG, waitpid will block, can't short-circuit */
- }
-#endif
+ is_special = strchr(is_special, ch);
+ is_blank = strchr(defifs, ch);
-/* Do we do this right?
- * bash-3.00# sleep 20 | false
- * <ctrl-Z pressed>
- * [3]+ Stopped sleep 20 | false
- * bash-3.00# echo $?
- * 1 <========== bg pipe is not fully done, but exitcode is already known!
- * [hush 1.14.0: yes we do it right]
- */
- wait_more:
- while (1) {
- int i;
- int dead;
+ if (!is_special && !is_blank) { /* ordinary char */
+ ordinary_char:
+ o_addQchr(&dest, ch);
+ if ((dest.o_assignment == MAYBE_ASSIGNMENT
+ || dest.o_assignment == WORD_IS_KEYWORD)
+ && ch == '='
+ && is_well_formed_var_name(dest.data, '=')
+ ) {
+ dest.o_assignment = DEFINITELY_ASSIGNMENT;
+ }
+ continue;
+ }
-#if ENABLE_HUSH_FAST
- i = G.count_SIGCHLD;
-#endif
- childpid = waitpid(-1, &status, attributes);
- if (childpid <= 0) {
- if (childpid && errno != ECHILD)
- bb_perror_msg("waitpid");
-#if ENABLE_HUSH_FAST
- else { /* Until next SIGCHLD, waitpid's are useless */
- G.we_have_children = (childpid == 0);
- G.handled_SIGCHLD = i;
-//bb_error_msg("[%d] checkjobs: waitpid returned <= 0, G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+ if (is_blank) {
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
}
+ if (ch == '\n') {
+#if ENABLE_HUSH_CASE
+ /* "case ... in <newline> word) ..." -
+ * newlines are ignored (but ';' wouldn't be) */
+ if (ctx.command->argv == NULL
+ && ctx.ctx_res_w == RES_MATCH
+ ) {
+ continue;
+ }
#endif
- break;
+ /* Treat newline as a command separator. */
+ done_pipe(&ctx, PIPE_SEQ);
+ debug_printf_parse("heredoc_cnt:%d\n", heredoc_cnt);
+ if (heredoc_cnt) {
+ if (fetch_heredocs(heredoc_cnt, &ctx, input)) {
+ goto parse_error;
+ }
+ heredoc_cnt = 0;
+ }
+ dest.o_assignment = MAYBE_ASSIGNMENT;
+ ch = ';';
+ /* note: if (is_blank) continue;
+ * will still trigger for us */
+ }
}
- dead = WIFEXITED(status) || WIFSIGNALED(status);
-#if DEBUG_JOBS
- if (WIFSTOPPED(status))
- debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n",
- childpid, WSTOPSIG(status), WEXITSTATUS(status));
- if (WIFSIGNALED(status))
- debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n",
- childpid, WTERMSIG(status), WEXITSTATUS(status));
- if (WIFEXITED(status))
- debug_printf_jobs("pid %d exited, exitcode %d\n",
- childpid, WEXITSTATUS(status));
-#endif
- /* Were we asked to wait for fg pipe? */
- if (fg_pipe) {
- for (i = 0; i < fg_pipe->num_cmds; i++) {
- debug_printf_jobs("check pid %d\n", fg_pipe->cmds[i].pid);
- if (fg_pipe->cmds[i].pid != childpid)
- continue;
- if (dead) {
- fg_pipe->cmds[i].pid = 0;
- fg_pipe->alive_cmds--;
- if (i == fg_pipe->num_cmds - 1) {
- /* last process gives overall exitstatus */
- rcode = WEXITSTATUS(status);
- /* bash prints killer signal's name for *last*
- * process in pipe (prints just newline for SIGINT).
- * Mimic this. Example: "sleep 5" + (^\ or kill -QUIT)
- */
- if (WIFSIGNALED(status)) {
- int sig = WTERMSIG(status);
- printf("%s\n", sig == SIGINT ? "" : get_signame(sig));
- /* TODO: MIPS has 128 sigs (1..128), what if sig==128 here?
- * Maybe we need to use sig | 128? */
- rcode = sig + 128;
- }
- IF_HAS_KEYWORDS(if (fg_pipe->pi_inverted) rcode = !rcode;)
- }
- } else {
- fg_pipe->cmds[i].is_stopped = 1;
- fg_pipe->stopped_cmds++;
- }
- debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n",
- fg_pipe->alive_cmds, fg_pipe->stopped_cmds);
- if (fg_pipe->alive_cmds - fg_pipe->stopped_cmds <= 0) {
- /* All processes in fg pipe have exited or stopped */
-/* Note: *non-interactive* bash does not continue if all processes in fg pipe
- * are stopped. Testcase: "cat | cat" in a script (not on command line!)
- * and "killall -STOP cat" */
- if (G_interactive_fd) {
-#if ENABLE_HUSH_JOB
- if (fg_pipe->alive_cmds)
- insert_bg_job(fg_pipe);
-#endif
- return rcode;
- }
- if (!fg_pipe->alive_cmds)
- return rcode;
- }
- /* There are still running processes in the fg pipe */
- goto wait_more; /* do waitpid again */
+ /* "cmd}" or "cmd }..." without semicolon or &:
+ * } is an ordinary char in this case, even inside { cmd; }
+ * Pathological example: { ""}; } should exec "}" cmd
+ */
+ if (ch == '}') {
+ if (!IS_NULL_CMD(ctx.command) /* cmd } */
+ || dest.length != 0 /* word} */
+ || dest.has_quoted_part /* ""} */
+ ) {
+ goto ordinary_char;
}
- /* it wasnt fg_pipe, look for process in bg pipes */
+ if (!IS_NULL_PIPE(ctx.pipe)) /* cmd | } */
+ goto skip_end_trigger;
+ /* else: } does terminate a group */
}
-#if ENABLE_HUSH_JOB
- /* We asked to wait for bg or orphaned children */
- /* No need to remember exitcode in this case */
- for (pi = G.job_list; pi; pi = pi->next) {
- for (i = 0; i < pi->num_cmds; i++) {
- if (pi->cmds[i].pid == childpid)
- goto found_pi_and_prognum;
+ if (end_trigger && end_trigger == ch
+ && (ch != ';' || heredoc_cnt == 0)
+#if ENABLE_HUSH_CASE
+ && (ch != ')'
+ || ctx.ctx_res_w != RES_MATCH
+ || (!dest.has_quoted_part && strcmp(dest.data, "esac") == 0)
+ )
+#endif
+ ) {
+ if (heredoc_cnt) {
+ /* This is technically valid:
+ * { cat <<HERE; }; echo Ok
+ * heredoc
+ * heredoc
+ * HERE
+ * but we don't support this.
+ * We require heredoc to be in enclosing {}/(),
+ * if any.
+ */
+ syntax_error_unterm_str("here document");
+ goto parse_error;
+ }
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
+ }
+ done_pipe(&ctx, PIPE_SEQ);
+ dest.o_assignment = MAYBE_ASSIGNMENT;
+ /* Do we sit outside of any if's, loops or case's? */
+ if (!HAS_KEYWORDS
+ IF_HAS_KEYWORDS(|| (ctx.ctx_res_w == RES_NONE && ctx.old_flag == 0))
+ ) {
+ o_free(&dest);
+#if !BB_MMU
+ debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
+ if (pstring)
+ *pstring = ctx.as_string.data;
+ else
+ o_free_unsafe(&ctx.as_string);
+#endif
+ debug_leave();
+ debug_printf_parse("parse_stream return %p: "
+ "end_trigger char found\n",
+ ctx.list_head);
+ return ctx.list_head;
}
}
- /* Happens when shell is used as init process (init=/bin/sh) */
- debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
- continue; /* do waitpid again */
+ skip_end_trigger:
+ if (is_blank)
+ continue;
- found_pi_and_prognum:
- if (dead) {
- /* child exited */
- pi->cmds[i].pid = 0;
- pi->alive_cmds--;
- if (!pi->alive_cmds) {
- if (G_interactive_fd)
- printf(JOB_STATUS_FORMAT, pi->jobid,
- "Done", pi->cmdtext);
- delete_finished_bg_job(pi);
+ /* Catch <, > before deciding whether this word is
+ * an assignment. a=1 2>z b=2: b=2 is still assignment */
+ switch (ch) {
+ case '>':
+ redir_fd = redirect_opt_num(&dest);
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
+ }
+ redir_style = REDIRECT_OVERWRITE;
+ if (next == '>') {
+ redir_style = REDIRECT_APPEND;
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ }
+#if 0
+ else if (next == '(') {
+ syntax_error(">(process) not supported");
+ goto parse_error;
}
- } else {
- /* child stopped */
- pi->cmds[i].is_stopped = 1;
- pi->stopped_cmds++;
- }
#endif
- } /* while (waitpid succeeds)... */
-
- return rcode;
-}
-
-#if ENABLE_HUSH_JOB
-static int checkjobs_and_fg_shell(struct pipe* fg_pipe)
-{
- pid_t p;
- int rcode = checkjobs(fg_pipe);
- if (G_saved_tty_pgrp) {
- /* Job finished, move the shell to the foreground */
- p = getpgrp(); /* our process group id */
- debug_printf_jobs("fg'ing ourself: getpgrp()=%d\n", (int)p);
- tcsetpgrp(G_interactive_fd, p);
- }
- return rcode;
-}
+ if (parse_redirect(&ctx, redir_fd, redir_style, input))
+ goto parse_error;
+ continue; /* back to top of while (1) */
+ case '<':
+ redir_fd = redirect_opt_num(&dest);
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
+ }
+ redir_style = REDIRECT_INPUT;
+ if (next == '<') {
+ redir_style = REDIRECT_HEREDOC;
+ heredoc_cnt++;
+ debug_printf_parse("++heredoc_cnt=%d\n", heredoc_cnt);
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ } else if (next == '>') {
+ redir_style = REDIRECT_IO;
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ }
+#if 0
+ else if (next == '(') {
+ syntax_error("<(process) not supported");
+ goto parse_error;
+ }
#endif
+ if (parse_redirect(&ctx, redir_fd, redir_style, input))
+ goto parse_error;
+ continue; /* back to top of while (1) */
+ }
-/* Start all the jobs, but don't wait for anything to finish.
- * See checkjobs().
- *
- * Return code is normally -1, when the caller has to wait for children
- * to finish to determine the exit status of the pipe. If the pipe
- * is a simple builtin command, however, the action is done by the
- * time run_pipe returns, and the exit code is provided as the
- * return value.
- *
- * Returns -1 only if started some children. IOW: we have to
- * mask out retvals of builtins etc with 0xff!
- *
- * The only case when we do not need to [v]fork is when the pipe
- * is single, non-backgrounded, non-subshell command. Examples:
- * cmd ; ... { list } ; ...
- * cmd && ... { list } && ...
- * cmd || ... { list } || ...
- * If it is, then we can run cmd as a builtin, NOFORK [do we do this?],
- * or (if SH_STANDALONE) an applet, and we can run the { list }
- * with run_list. If it isn't one of these, we fork and exec cmd.
- *
- * Cases when we must fork:
- * non-single: cmd | cmd
- * backgrounded: cmd & { list } &
- * subshell: ( list ) [&]
- */
-static NOINLINE int run_pipe(struct pipe *pi)
-{
- static const char *const null_ptr = NULL;
-
- int cmd_no;
- int next_infd;
- struct command *command;
- char **argv_expanded;
- char **argv;
- char *p;
- /* it is not always needed, but we aim to smaller code */
- int squirrel[] = { -1, -1, -1 };
- int rcode;
-
- debug_printf_exec("run_pipe start: members:%d\n", pi->num_cmds);
- debug_enter();
-
- IF_HUSH_JOB(pi->pgrp = -1;)
- pi->stopped_cmds = 0;
- command = &pi->cmds[0];
- argv_expanded = NULL;
-
- if (pi->num_cmds != 1
- || pi->followup == PIPE_BG
- || command->cmd_type == CMD_SUBSHELL
- ) {
- goto must_fork;
- }
+ if (dest.o_assignment == MAYBE_ASSIGNMENT
+ /* check that we are not in word in "a=1 2>word b=1": */
+ && !ctx.pending_redirect
+ ) {
+ /* ch is a special char and thus this word
+ * cannot be an assignment */
+ dest.o_assignment = NOT_ASSIGNMENT;
+ }
- pi->alive_cmds = 1;
+ /* Note: nommu_addchr(&ctx.as_string, ch) is already done */
- debug_printf_exec(": group:%p argv:'%s'\n",
- command->group, command->argv ? command->argv[0] : "NONE");
-
- if (command->group) {
-#if ENABLE_HUSH_FUNCTIONS
- if (command->cmd_type == CMD_FUNCDEF) {
- /* "executing" func () { list } */
- struct function *funcp;
+ switch (ch) {
+ case '#':
+ if (dest.length == 0) {
+ while (1) {
+ ch = i_peek(input);
+ if (ch == EOF || ch == '\n')
+ break;
+ i_getch(input);
+ /* note: we do not add it to &ctx.as_string */
+ }
+ nommu_addchr(&ctx.as_string, '\n');
+ } else {
+ o_addQchr(&dest, ch);
+ }
+ break;
+ case '\\':
+ if (next == EOF) {
+ syntax_error("\\<eof>");
+ xfunc_die();
+ }
+ ch = i_getch(input);
+ if (ch != '\n') {
+ o_addchr(&dest, '\\');
+ /*nommu_addchr(&ctx.as_string, '\\'); - already done */
+ o_addchr(&dest, ch);
+ nommu_addchr(&ctx.as_string, ch);
+ /* Example: echo Hello \2>file
+ * we need to know that word 2 is quoted */
+ dest.has_quoted_part = 1;
+ }
+#if !BB_MMU
+ else {
+ /* It's "\<newline>". Remove trailing '\' from ctx.as_string */
+ ctx.as_string.data[--ctx.as_string.length] = '\0';
+ }
+#endif
+ break;
+ case '$':
+ if (parse_dollar(&ctx.as_string, &dest, input) != 0) {
+ debug_printf_parse("parse_stream parse error: "
+ "parse_dollar returned non-0\n");
+ goto parse_error;
+ }
+ break;
+ case '\'':
+ dest.has_quoted_part = 1;
+ while (1) {
+ ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('\'');
+ /*xfunc_die(); - redundant */
+ }
+ nommu_addchr(&ctx.as_string, ch);
+ if (ch == '\'')
+ break;
+ o_addqchr(&dest, ch);
+ }
+ break;
+ case '"':
+ dest.has_quoted_part = 1;
+ is_in_dquote ^= 1; /* invert */
+ if (dest.o_assignment == NOT_ASSIGNMENT)
+ dest.o_expflags ^= EXP_FLAG_ESC_GLOB_CHARS;
+ break;
+#if ENABLE_HUSH_TICK
+ case '`': {
+ unsigned pos;
- funcp = new_function(command->argv[0]);
- /* funcp->name is already set to argv[0] */
- funcp->body = command->group;
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(&dest, '`');
+ pos = dest.length;
+ add_till_backquote(&dest, input);
# if !BB_MMU
- funcp->body_as_string = command->group_as_string;
- command->group_as_string = NULL;
+ o_addstr(&ctx.as_string, dest.data + pos);
+ o_addchr(&ctx.as_string, '`');
# endif
- command->group = NULL;
- command->argv[0] = NULL;
- debug_printf_exec("cmd %p has child func at %p\n", command, funcp);
- funcp->parent_cmd = command;
- command->child_func = funcp;
-
- debug_printf_exec("run_pipe: return EXIT_SUCCESS\n");
- debug_leave();
- return EXIT_SUCCESS;
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ //debug_printf_subst("SUBST RES3 '%s'\n", dest.data + pos);
+ break;
}
#endif
- /* { list } */
- debug_printf("non-subshell group\n");
- rcode = 1; /* exitcode if redir failed */
- if (setup_redirects(command, squirrel) == 0) {
- debug_printf_exec(": run_list\n");
- rcode = run_list(command->group) & 0xff;
- }
- restore_redirects(squirrel);
- IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
- debug_leave();
- debug_printf_exec("run_pipe: return %d\n", rcode);
- return rcode;
- }
-
- argv = command->argv ? command->argv : (char **) &null_ptr;
- {
- const struct built_in_command *x;
-#if ENABLE_HUSH_FUNCTIONS
- const struct function *funcp;
-#else
- enum { funcp = 0 };
+ case ';':
+#if ENABLE_HUSH_CASE
+ case_semi:
#endif
- char **new_env = NULL;
- struct variable *old_vars = NULL;
-
- if (argv[command->assignment_cnt] == NULL) {
- /* Assignments, but no command */
- /* Ensure redirects take effect (that is, create files).
- * Try "a=t >file": */
- rcode = setup_redirects(command, squirrel);
- restore_redirects(squirrel);
- /* Set shell variables */
- if (G.x_mode)
- bb_putchar_stderr('+');
- while (*argv) {
- p = expand_string_to_string(*argv);
- if (G.x_mode)
- fprintf(stderr, " %s", p);
- debug_printf_exec("set shell var:'%s'->'%s'\n",
- *argv, p);
- set_local_var(p, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
- argv++;
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
}
- if (G.x_mode)
- bb_putchar_stderr('\n');
- /* Redirect error sets $? to 1. Otherwise,
- * if evaluating assignment value set $?, retain it.
- * Try "false; q=`exit 2`; echo $?" - should print 2: */
- if (rcode == 0)
- rcode = G.last_exitcode;
- /* Do we need to flag set_local_var() errors?
- * "assignment to readonly var" and "putenv error"
- */
- IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
- debug_leave();
- debug_printf_exec("run_pipe: return %d\n", rcode);
- return rcode;
- }
-
- /* Expand the rest into (possibly) many strings each */
- if (0) {}
-#if ENABLE_HUSH_BASH_COMPAT
- else if (command->cmd_type == CMD_SINGLEWORD_NOGLOB) {
- argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt);
- }
-#endif
-#ifdef CMD_SINGLEWORD_NOGLOB_COND
- else if (command->cmd_type == CMD_SINGLEWORD_NOGLOB_COND) {
- argv_expanded = expand_strvec_to_strvec_singleword_noglob_cond(argv + command->assignment_cnt);
-
- }
-#endif
- else {
- argv_expanded = expand_strvec_to_strvec(argv + command->assignment_cnt);
- }
-
- /* if someone gives us an empty string: `cmd with empty output` */
- if (!argv_expanded[0]) {
- free(argv_expanded);
- debug_leave();
- return G.last_exitcode;
- }
-
- x = find_builtin(argv_expanded[0]);
-#if ENABLE_HUSH_FUNCTIONS
- funcp = NULL;
- if (!x)
- funcp = find_function(argv_expanded[0]);
-#endif
- if (x || funcp) {
- if (!funcp) {
- if (x->b_function == builtin_exec && argv_expanded[1] == NULL) {
- debug_printf("exec with redirects only\n");
- rcode = setup_redirects(command, NULL);
- goto clean_up_and_ret1;
+ done_pipe(&ctx, PIPE_SEQ);
+#if ENABLE_HUSH_CASE
+ /* Eat multiple semicolons, detect
+ * whether it means something special */
+ while (1) {
+ ch = i_peek(input);
+ if (ch != ';')
+ break;
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ if (ctx.ctx_res_w == RES_CASE_BODY) {
+ ctx.ctx_dsemicolon = 1;
+ ctx.ctx_res_w = RES_MATCH;
+ break;
}
}
- /* setup_redirects acts on file descriptors, not FILEs.
- * This is perfect for work that comes after exec().
- * Is it really safe for inline use? Experimentally,
- * things seem to work. */
- rcode = setup_redirects(command, squirrel);
- if (rcode == 0) {
- new_env = expand_assignments(argv, command->assignment_cnt);
- dump_cmd_in_x_mode(new_env);
- dump_cmd_in_x_mode(argv_expanded);
- old_vars = set_vars_and_save_old(new_env);
- if (!funcp) {
- debug_printf_exec(": builtin '%s' '%s'...\n",
- x->b_cmd, argv_expanded[1]);
- rcode = x->b_function(argv_expanded) & 0xff;
- fflush_all();
- }
-#if ENABLE_HUSH_FUNCTIONS
- else {
-# if ENABLE_HUSH_LOCAL
- struct variable **sv;
- sv = G.shadowed_vars_pp;
- G.shadowed_vars_pp = &old_vars;
-# endif
- debug_printf_exec(": function '%s' '%s'...\n",
- funcp->name, argv_expanded[1]);
- rcode = run_function(funcp, argv_expanded) & 0xff;
-# if ENABLE_HUSH_LOCAL
- G.shadowed_vars_pp = sv;
-# endif
- }
#endif
+ new_cmd:
+ /* We just finished a cmd. New one may start
+ * with an assignment */
+ dest.o_assignment = MAYBE_ASSIGNMENT;
+ break;
+ case '&':
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
}
- clean_up_and_ret:
- restore_redirects(squirrel);
- unset_vars(new_env);
- add_vars(old_vars);
- clean_up_and_ret1:
- free(argv_expanded);
- IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
- debug_leave();
- debug_printf_exec("run_pipe return %d\n", rcode);
- return rcode;
- }
-
- if (ENABLE_FEATURE_SH_STANDALONE) {
- int n = find_applet_by_name(argv_expanded[0]);
- if (n >= 0 && APPLET_IS_NOFORK(n)) {
- rcode = setup_redirects(command, squirrel);
- if (rcode == 0) {
- new_env = expand_assignments(argv, command->assignment_cnt);
- dump_cmd_in_x_mode(new_env);
- dump_cmd_in_x_mode(argv_expanded);
- old_vars = set_vars_and_save_old(new_env);
- debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
- argv_expanded[0], argv_expanded[1]);
- rcode = run_nofork_applet(n, argv_expanded);
- }
- goto clean_up_and_ret;
+ if (next == '&') {
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ done_pipe(&ctx, PIPE_AND);
+ } else {
+ done_pipe(&ctx, PIPE_BG);
}
- }
- /* It is neither builtin nor applet. We must fork. */
- }
-
- must_fork:
- /* NB: argv_expanded may already be created, and that
- * might include `cmd` runs! Do not rerun it! We *must*
- * use argv_expanded if it's non-NULL */
-
- /* Going to fork a child per each pipe member */
- pi->alive_cmds = 0;
- next_infd = 0;
-
- cmd_no = 0;
- while (cmd_no < pi->num_cmds) {
- struct fd_pair pipefds;
+ goto new_cmd;
+ case '|':
+ if (done_word(&dest, &ctx)) {
+ goto parse_error;
+ }
+#if ENABLE_HUSH_CASE
+ if (ctx.ctx_res_w == RES_MATCH)
+ break; /* we are in case's "word | word)" */
+#endif
+ if (next == '|') { /* || */
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ done_pipe(&ctx, PIPE_OR);
+ } else {
+ /* we could pick up a file descriptor choice here
+ * with redirect_opt_num(), but bash doesn't do it.
+ * "echo foo 2| cat" yields "foo 2". */
+ done_command(&ctx);
#if !BB_MMU
- volatile nommu_save_t nommu_save;
- nommu_save.new_env = NULL;
- nommu_save.old_vars = NULL;
- nommu_save.argv = NULL;
- nommu_save.argv_from_re_execing = NULL;
+ o_reset_to_empty_unquoted(&ctx.as_string);
#endif
- command = &pi->cmds[cmd_no];
- cmd_no++;
- if (command->argv) {
- debug_printf_exec(": pipe member '%s' '%s'...\n",
- command->argv[0], command->argv[1]);
- } else {
- debug_printf_exec(": pipe member with no argv\n");
- }
-
- /* pipes are inserted between pairs of commands */
- pipefds.rd = 0;
- pipefds.wr = 1;
- if (cmd_no < pi->num_cmds)
- xpiped_pair(pipefds);
-
- command->pid = BB_MMU ? fork() : vfork();
- if (!command->pid) { /* child */
-#if ENABLE_HUSH_JOB
- disable_restore_tty_pgrp_on_exit();
- CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
-
- /* Every child adds itself to new process group
- * with pgid == pid_of_first_child_in_pipe */
- if (G.run_list_level == 1 && G_interactive_fd) {
- pid_t pgrp;
- pgrp = pi->pgrp;
- if (pgrp < 0) /* true for 1st process only */
- pgrp = getpid();
- if (setpgid(0, pgrp) == 0
- && pi->followup != PIPE_BG
- && G_saved_tty_pgrp /* we have ctty */
- ) {
- /* We do it in *every* child, not just first,
- * to avoid races */
- tcsetpgrp(G_interactive_fd, pgrp);
- }
+ }
+ goto new_cmd;
+ case '(':
+#if ENABLE_HUSH_CASE
+ /* "case... in [(]word)..." - skip '(' */
+ if (ctx.ctx_res_w == RES_MATCH
+ && ctx.command->argv == NULL /* not (word|(... */
+ && dest.length == 0 /* not word(... */
+ && dest.has_quoted_part == 0 /* not ""(... */
+ ) {
+ continue;
}
#endif
- if (pi->alive_cmds == 0 && pi->followup == PIPE_BG) {
- /* 1st cmd in backgrounded pipe
- * should have its stdin /dev/null'ed */
- close(0);
- if (open(bb_dev_null, O_RDONLY))
- xopen("/", O_RDONLY);
- } else {
- xmove_fd(next_infd, 0);
+ case '{':
+ if (parse_group(&dest, &ctx, input, ch) != 0) {
+ goto parse_error;
}
- xmove_fd(pipefds.wr, 1);
- if (pipefds.rd > 1)
- close(pipefds.rd);
- /* Like bash, explicit redirects override pipes,
- * and the pipe fd is available for dup'ing. */
- if (setup_redirects(command, NULL))
- _exit(1);
-
- /* Restore default handlers just prior to exec */
- /*signal(SIGCHLD, SIG_DFL); - so far we don't have any handlers */
-
- /* Stores to nommu_save list of env vars putenv'ed
- * (NOMMU, on MMU we don't need that) */
- /* cast away volatility... */
- pseudo_exec((nommu_save_t*) &nommu_save, command, argv_expanded);
- /* pseudo_exec() does not return */
+ goto new_cmd;
+ case ')':
+#if ENABLE_HUSH_CASE
+ if (ctx.ctx_res_w == RES_MATCH)
+ goto case_semi;
+#endif
+ case '}':
+ /* proper use of this character is caught by end_trigger:
+ * if we see {, we call parse_group(..., end_trigger='}')
+ * and it will match } earlier (not here). */
+ syntax_error_unexpected_ch(ch);
+ goto parse_error;
+ default:
+ if (HUSH_DEBUG)
+ bb_error_msg_and_die("BUG: unexpected %c\n", ch);
}
+ } /* while (1) */
- /* parent or error */
-#if ENABLE_HUSH_FAST
- G.count_SIGCHLD++;
-//bb_error_msg("[%d] fork in run_pipe: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
-#endif
- enable_restore_tty_pgrp_on_exit();
+ parse_error:
+ {
+ struct parse_context *pctx;
+ IF_HAS_KEYWORDS(struct parse_context *p2;)
+
+ /* Clean up allocated tree.
+ * Sample for finding leaks on syntax error recovery path.
+ * Run it from interactive shell, watch pmap `pidof hush`.
+ * while if false; then false; fi; do break; fi
+ * Samples to catch leaks at execution:
+ * while if (true | {true;}); then echo ok; fi; do break; done
+ * while if (true | {true;}); then echo ok; fi; do (if echo ok; break; then :; fi) | cat; break; done
+ */
+ pctx = &ctx;
+ do {
+ /* Update pipe/command counts,
+ * otherwise freeing may miss some */
+ done_pipe(pctx, PIPE_SEQ);
+ debug_printf_clean("freeing list %p from ctx %p\n",
+ pctx->list_head, pctx);
+ debug_print_tree(pctx->list_head, 0);
+ free_pipe_list(pctx->list_head);
+ debug_printf_clean("freed list %p\n", pctx->list_head);
#if !BB_MMU
- /* Clean up after vforked child */
- free(nommu_save.argv);
- free(nommu_save.argv_from_re_execing);
- unset_vars(nommu_save.new_env);
- add_vars(nommu_save.old_vars);
+ o_free_unsafe(&pctx->as_string);
#endif
- free(argv_expanded);
- argv_expanded = NULL;
- if (command->pid < 0) { /* [v]fork failed */
- /* Clearly indicate, was it fork or vfork */
- bb_perror_msg(BB_MMU ? "vfork"+1 : "vfork");
- } else {
- pi->alive_cmds++;
-#if ENABLE_HUSH_JOB
- /* Second and next children need to know pid of first one */
- if (pi->pgrp < 0)
- pi->pgrp = command->pid;
+ IF_HAS_KEYWORDS(p2 = pctx->stack;)
+ if (pctx != &ctx) {
+ free(pctx);
+ }
+ IF_HAS_KEYWORDS(pctx = p2;)
+ } while (HAS_KEYWORDS && pctx);
+ /* Free text, clear all dest fields */
+ o_free(&dest);
+ /* If we are not in top-level parse, we return,
+ * our caller will propagate error.
+ */
+ if (end_trigger != ';') {
+#if !BB_MMU
+ if (pstring)
+ *pstring = NULL;
#endif
+ debug_leave();
+ return ERR_PTR;
}
-
- if (cmd_no > 1)
- close(next_infd);
- if (cmd_no < pi->num_cmds)
- close(pipefds.wr);
- /* Pass read (output) pipe end to next iteration */
- next_infd = pipefds.rd;
+ /* Discard cached input, force prompt */
+ input->p = NULL;
+ IF_HUSH_INTERACTIVE(input->promptme = 1;)
+ goto reset;
}
+}
- if (!pi->alive_cmds) {
- debug_leave();
- debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n");
- return 1;
- }
- debug_leave();
- debug_printf_exec("run_pipe return -1 (%u children started)\n", pi->alive_cmds);
- return -1;
+/*** Execution routines ***/
+
+/* Expansion can recurse, need forward decls: */
+static char *expand_string_to_string(const char *str);
+static int process_command_subs(o_string *dest, const char *s);
+
+/* expand_strvec_to_strvec() takes a list of strings, expands
+ * all variable references within and returns a pointer to
+ * a list of expanded strings, possibly with larger number
+ * of strings. (Think VAR="a b"; echo $VAR).
+ * This new list is allocated as a single malloc block.
+ * NULL-terminated list of char* pointers is at the beginning of it,
+ * followed by strings themselves.
+ * Caller can deallocate entire list by single free(list). */
+
+/* Store given string, finalizing the word and starting new one whenever
+ * we encounter IFS char(s). This is used for expanding variable values.
+ * End-of-string does NOT finalize word: think about 'echo -$VAR-' */
+static int expand_on_ifs(o_string *output, int n, const char *str)
+{
+ while (1) {
+ int word_len = strcspn(str, G.ifs);
+ if (word_len) {
+ if (output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)
+ o_addqblock(output, str, word_len);
+ else if (!(output->o_expflags & EXP_FLAG_GLOB))
+ o_addblock(output, str, word_len);
+ else /* if (!escape && glob) */ {
+ /* Protect backslashes against globbing up :)
+ * Example: "v='\*'; echo b$v"
+ */
+ o_addblock_duplicate_backslash(output, str, word_len);
+ /*/ Why can't we do it easier? */
+ /*o_addblock(output, str, word_len); - WRONG: "v='\*'; echo Z$v" prints "Z*" instead of "Z\*" */
+ /*o_addqblock(output, str, word_len); - WRONG: "v='*'; echo Z$v" prints "Z*" instead of Z* files */
+ }
+ str += word_len;
+ }
+ if (!*str) /* EOL - do not finalize word */
+ break;
+ o_addchr(output, '\0');
+ debug_print_list("expand_on_ifs", output, n);
+ n = o_save_ptr(output, n);
+ str += strspn(str, G.ifs); /* skip ifs chars */
+ }
+ debug_print_list("expand_on_ifs[1]", output, n);
+ return n;
}
-#ifndef debug_print_tree
-static void debug_print_tree(struct pipe *pi, int lvl)
+/* Helper to expand $((...)) and heredoc body. These act as if
+ * they are in double quotes, with the exception that they are not :).
+ * Just the rules are similar: "expand only $var and `cmd`"
+ *
+ * Returns malloced string.
+ * As an optimization, we return NULL if expansion is not needed.
+ */
+static char *expand_pseudo_dquoted(const char *str)
{
- static const char *const PIPE[] = {
- [PIPE_SEQ] = "SEQ",
- [PIPE_AND] = "AND",
- [PIPE_OR ] = "OR" ,
- [PIPE_BG ] = "BG" ,
- };
- static const char *RES[] = {
- [RES_NONE ] = "NONE" ,
-# if ENABLE_HUSH_IF
- [RES_IF ] = "IF" ,
- [RES_THEN ] = "THEN" ,
- [RES_ELIF ] = "ELIF" ,
- [RES_ELSE ] = "ELSE" ,
- [RES_FI ] = "FI" ,
-# endif
-# if ENABLE_HUSH_LOOPS
- [RES_FOR ] = "FOR" ,
- [RES_WHILE] = "WHILE",
- [RES_UNTIL] = "UNTIL",
- [RES_DO ] = "DO" ,
- [RES_DONE ] = "DONE" ,
-# endif
-# if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
- [RES_IN ] = "IN" ,
-# endif
-# if ENABLE_HUSH_CASE
- [RES_CASE ] = "CASE" ,
- [RES_CASE_IN ] = "CASE_IN" ,
- [RES_MATCH] = "MATCH",
- [RES_CASE_BODY] = "CASE_BODY",
- [RES_ESAC ] = "ESAC" ,
-# endif
- [RES_XXXX ] = "XXXX" ,
- [RES_SNTX ] = "SNTX" ,
- };
- static const char *const CMDTYPE[] = {
- "{}",
- "()",
- "[noglob]",
-# if ENABLE_HUSH_FUNCTIONS
- "func()",
-# endif
- };
-
- int pin, prn;
-
- pin = 0;
- while (pi) {
- fprintf(stderr, "%*spipe %d res_word=%s followup=%d %s\n", lvl*2, "",
- pin, RES[pi->res_word], pi->followup, PIPE[pi->followup]);
- prn = 0;
- while (prn < pi->num_cmds) {
- struct command *command = &pi->cmds[prn];
- char **argv = command->argv;
+ char *exp_str;
+ struct in_str input;
+ o_string dest = NULL_O_STRING;
- fprintf(stderr, "%*s cmd %d assignment_cnt:%d",
- lvl*2, "", prn,
- command->assignment_cnt);
- if (command->group) {
- fprintf(stderr, " group %s: (argv=%p)%s%s\n",
- CMDTYPE[command->cmd_type],
- argv
-# if !BB_MMU
- , " group_as_string:", command->group_as_string
-# else
- , "", ""
-# endif
- );
- debug_print_tree(command->group, lvl+1);
- prn++;
- continue;
- }
- if (argv) while (*argv) {
- fprintf(stderr, " '%s'", *argv);
- argv++;
- }
- fprintf(stderr, "\n");
- prn++;
- }
- pi = pi->next;
- pin++;
+ if (!strchr(str, '$')
+ && !strchr(str, '\\')
+#if ENABLE_HUSH_TICK
+ && !strchr(str, '`')
+#endif
+ ) {
+ return NULL;
}
+
+ /* We need to expand. Example:
+ * echo $(($a + `echo 1`)) $((1 + $((2)) ))
+ */
+ setup_string_in_str(&input, str);
+ parse_stream_dquoted(NULL, &dest, &input, EOF);
+ //bb_error_msg("'%s' -> '%s'", str, dest.data);
+ exp_str = expand_string_to_string(dest.data);
+ //bb_error_msg("'%s' -> '%s'", dest.data, exp_str);
+ o_free_unsafe(&dest);
+ return exp_str;
}
-#endif /* debug_print_tree */
-/* NB: called by pseudo_exec, and therefore must not modify any
- * global data until exec/_exit (we can be a child after vfork!) */
-static int run_list(struct pipe *pi)
+#if ENABLE_SH_MATH_SUPPORT
+static arith_t expand_and_evaluate_arith(const char *arg, int *errcode_p)
{
-#if ENABLE_HUSH_CASE
- char *case_word = NULL;
-#endif
-#if ENABLE_HUSH_LOOPS
- struct pipe *loop_top = NULL;
- char **for_lcur = NULL;
- char **for_list = NULL;
-#endif
- smallint last_followup;
- smalluint rcode;
-#if ENABLE_HUSH_IF || ENABLE_HUSH_CASE
- smalluint cond_code = 0;
-#else
- enum { cond_code = 0 };
-#endif
-#if HAS_KEYWORDS
- smallint rword; /* enum reserved_style */
- smallint last_rword; /* ditto */
-#endif
+ arith_eval_hooks_t hooks;
+ arith_t res;
+ char *exp_str;
- debug_printf_exec("run_list start lvl %d\n", G.run_list_level);
- debug_enter();
+ hooks.lookupvar = get_local_var_value;
+ hooks.setvar = set_local_var_from_halves;
+ //hooks.endofname = endofname;
+ exp_str = expand_pseudo_dquoted(arg);
+ res = arith(exp_str ? exp_str : arg, errcode_p, &hooks);
+ free(exp_str);
+ return res;
+}
+#endif
-#if ENABLE_HUSH_LOOPS
- /* Check syntax for "for" */
- for (struct pipe *cpipe = pi; cpipe; cpipe = cpipe->next) {
- if (cpipe->res_word != RES_FOR && cpipe->res_word != RES_IN)
- continue;
- /* current word is FOR or IN (BOLD in comments below) */
- if (cpipe->next == NULL) {
- syntax_error("malformed for");
- debug_leave();
- debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
- return 1;
- }
- /* "FOR v; do ..." and "for v IN a b; do..." are ok */
- if (cpipe->next->res_word == RES_DO)
- continue;
- /* next word is not "do". It must be "in" then ("FOR v in ...") */
- if (cpipe->res_word == RES_IN /* "for v IN a b; not_do..."? */
- || cpipe->next->res_word != RES_IN /* FOR v not_do_and_not_in..."? */
- ) {
- syntax_error("malformed for");
- debug_leave();
- debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
- return 1;
+#if ENABLE_HUSH_BASH_COMPAT
+/* ${var/[/]pattern[/repl]} helpers */
+static char *strstr_pattern(char *val, const char *pattern, int *size)
+{
+ while (1) {
+ char *end = scan_and_match(val, pattern, SCAN_MOVE_FROM_RIGHT + SCAN_MATCH_LEFT_HALF);
+ debug_printf_varexp("val:'%s' pattern:'%s' end:'%s'\n", val, pattern, end);
+ if (end) {
+ *size = end - val;
+ return val;
}
+ if (*val == '\0')
+ return NULL;
+ /* Optimization: if "*pat" did not match the start of "string",
+ * we know that "tring", "ring" etc will not match too:
+ */
+ if (pattern[0] == '*')
+ return NULL;
+ val++;
}
-#endif
-
- /* Past this point, all code paths should jump to ret: label
- * in order to return, no direct "return" statements please.
- * This helps to ensure that no memory is leaked. */
+}
+static char *replace_pattern(char *val, const char *pattern, const char *repl, char exp_op)
+{
+ char *result = NULL;
+ unsigned res_len = 0;
+ unsigned repl_len = strlen(repl);
-#if ENABLE_HUSH_JOB
- G.run_list_level++;
-#endif
+ while (1) {
+ int size;
+ char *s = strstr_pattern(val, pattern, &size);
+ if (!s)
+ break;
-#if HAS_KEYWORDS
- rword = RES_NONE;
- last_rword = RES_XXXX;
-#endif
- last_followup = PIPE_SEQ;
- rcode = G.last_exitcode;
+ result = xrealloc(result, res_len + (s - val) + repl_len + 1);
+ memcpy(result + res_len, val, s - val);
+ res_len += s - val;
+ strcpy(result + res_len, repl);
+ res_len += repl_len;
+ debug_printf_varexp("val:'%s' s:'%s' result:'%s'\n", val, s, result);
- /* Go through list of pipes, (maybe) executing them. */
- for (; pi; pi = IF_HUSH_LOOPS(rword == RES_DONE ? loop_top : ) pi->next) {
- if (G.flag_SIGINT)
+ val = s + size;
+ if (exp_op == '/')
break;
+ }
+ if (val[0] && result) {
+ result = xrealloc(result, res_len + strlen(val) + 1);
+ strcpy(result + res_len, val);
+ debug_printf_varexp("val:'%s' result:'%s'\n", val, result);
+ }
+ debug_printf_varexp("result:'%s'\n", result);
+ return result;
+}
+#endif
- IF_HAS_KEYWORDS(rword = pi->res_word;)
- debug_printf_exec(": rword=%d cond_code=%d last_rword=%d\n",
- rword, cond_code, last_rword);
-#if ENABLE_HUSH_LOOPS
- if ((rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR)
- && loop_top == NULL /* avoid bumping G.depth_of_loop twice */
+/* Helper:
+ * Handles <SPECIAL_VAR_SYMBOL>varname...<SPECIAL_VAR_SYMBOL> construct.
+ */
+static NOINLINE const char *expand_one_var(char **to_be_freed_pp, char *arg, char **pp, char first_ch)
+{
+ const char *val = NULL;
+ char *to_be_freed = NULL;
+ char *p = *pp;
+ char *var;
+ char first_char;
+ char exp_op;
+ char exp_save = exp_save; /* for compiler */
+ char *exp_saveptr; /* points to expansion operator */
+ char *exp_word = exp_word; /* for compiler */
+
+ *p = '\0'; /* replace trailing SPECIAL_VAR_SYMBOL */
+ var = arg;
+ exp_saveptr = arg[1] ? strchr(VAR_ENCODED_SUBST_OPS, arg[1]) : NULL;
+ first_char = arg[0] = first_ch & 0x7f;
+ exp_op = 0;
+
+ if (first_char == '#' /* ${#... */
+ && arg[1] && !exp_saveptr /* not ${#} and not ${#<op_char>...} */
+ ) {
+ /* It must be length operator: ${#var} */
+ var++;
+ exp_op = 'L';
+ } else {
+ /* Maybe handle parameter expansion */
+ if (exp_saveptr /* if 2nd char is one of expansion operators */
+ && strchr(NUMERIC_SPECVARS_STR, first_char) /* 1st char is special variable */
) {
- /* start of a loop: remember where loop starts */
- loop_top = pi;
- G.depth_of_loop++;
- }
-#endif
- /* Still in the same "if...", "then..." or "do..." branch? */
- if (IF_HAS_KEYWORDS(rword == last_rword &&) 1) {
- if ((rcode == 0 && last_followup == PIPE_OR)
- || (rcode != 0 && last_followup == PIPE_AND)
- ) {
- /* It is "<true> || CMD" or "<false> && CMD"
- * and we should not execute CMD */
- debug_printf_exec("skipped cmd because of || or &&\n");
- last_followup = pi->followup;
- continue;
+ /* ${?:0}, ${#[:]%0} etc */
+ exp_saveptr = var + 1;
+ } else {
+ /* ${?}, ${var}, ${var:0}, ${var[:]%0} etc */
+ exp_saveptr = var+1 + strcspn(var+1, VAR_ENCODED_SUBST_OPS);
+ }
+ exp_op = exp_save = *exp_saveptr;
+ if (exp_op) {
+ exp_word = exp_saveptr + 1;
+ if (exp_op == ':') {
+ exp_op = *exp_word++;
+//TODO: try ${var:} and ${var:bogus} in non-bash config
+ if (ENABLE_HUSH_BASH_COMPAT
+ && (!exp_op || !strchr(MINUS_PLUS_EQUAL_QUESTION, exp_op))
+ ) {
+ /* oops... it's ${var:N[:M]}, not ${var:?xxx} or some such */
+ exp_op = ':';
+ exp_word--;
+ }
}
- }
- last_followup = pi->followup;
- IF_HAS_KEYWORDS(last_rword = rword;)
-#if ENABLE_HUSH_IF
- if (cond_code) {
- if (rword == RES_THEN) {
- /* if false; then ... fi has exitcode 0! */
- G.last_exitcode = rcode = EXIT_SUCCESS;
- /* "if <false> THEN cmd": skip cmd */
- continue;
+ *exp_saveptr = '\0';
+ } /* else: it's not an expansion op, but bare ${var} */
+ }
+
+ /* Look up the variable in question */
+ if (isdigit(var[0])) {
+ /* parse_dollar() should have vetted var for us */
+ int n = xatoi_positive(var);
+ if (n < G.global_argc)
+ val = G.global_argv[n];
+ /* else val remains NULL: $N with too big N */
+ } else {
+ switch (var[0]) {
+ case '$': /* pid */
+ val = utoa(G.root_pid);
+ break;
+ case '!': /* bg pid */
+ val = G.last_bg_pid ? utoa(G.last_bg_pid) : "";
+ break;
+ case '?': /* exitcode */
+ val = utoa(G.last_exitcode);
+ break;
+ case '#': /* argc */
+ val = utoa(G.global_argc ? G.global_argc-1 : 0);
+ break;
+ default:
+ val = get_local_var_value(var);
+ }
+ }
+
+ /* Handle any expansions */
+ if (exp_op == 'L') {
+ debug_printf_expand("expand: length(%s)=", val);
+ val = utoa(val ? strlen(val) : 0);
+ debug_printf_expand("%s\n", val);
+ } else if (exp_op) {
+ if (exp_op == '%' || exp_op == '#') {
+ /* Standard-mandated substring removal ops:
+ * ${parameter%word} - remove smallest suffix pattern
+ * ${parameter%%word} - remove largest suffix pattern
+ * ${parameter#word} - remove smallest prefix pattern
+ * ${parameter##word} - remove largest prefix pattern
+ *
+ * Word is expanded to produce a glob pattern.
+ * Then var's value is matched to it and matching part removed.
+ */
+ if (val && val[0]) {
+ char *exp_exp_word;
+ char *loc;
+ unsigned scan_flags = pick_scan(exp_op, *exp_word);
+ if (exp_op == *exp_word) /* ## or %% */
+ exp_word++;
+//TODO: avoid xstrdup unless needed
+// (see HACK ALERT below for an example)
+ val = to_be_freed = xstrdup(val);
+//TODO: fix expansion rules:
+ exp_exp_word = expand_pseudo_dquoted(exp_word);
+ if (exp_exp_word)
+ exp_word = exp_exp_word;
+ loc = scan_and_match(to_be_freed, exp_word, scan_flags);
+ //bb_error_msg("op:%c str:'%s' pat:'%s' res:'%s'",
+ // exp_op, to_be_freed, exp_word, loc);
+ free(exp_exp_word);
+ if (loc) { /* match was found */
+ if (scan_flags & SCAN_MATCH_LEFT_HALF) /* #[#] */
+ val = loc;
+ else /* %[%] */
+ *loc = '\0';
+ }
}
- } else {
- if (rword == RES_ELSE || rword == RES_ELIF) {
- /* "if <true> then ... ELSE/ELIF cmd":
- * skip cmd and all following ones */
- break;
+ }
+#if ENABLE_HUSH_BASH_COMPAT
+ else if (exp_op == '/' || exp_op == '\\') {
+ /* It's ${var/[/]pattern[/repl]} thing.
+ * Note that in encoded form it has TWO parts:
+ * var/pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL>
+ */
+ /* Empty variable always gives nothing: */
+ // "v=''; echo ${v/*/w}" prints "", not "w"
+ if (val && val[0]) {
+ /* It's ${var/[/]pattern[/repl]} thing */
+ /*
+ * Pattern is taken literally, while
+ * repl should be unbackslashed and globbed
+ * by the usual expansion rules:
+ * >az; >bz;
+ * v='a bz'; echo "${v/a*z/a*z}" prints "a*z"
+ * v='a bz'; echo "${v/a*z/\z}" prints "\z"
+ * v='a bz'; echo ${v/a*z/a*z} prints "az"
+ * v='a bz'; echo ${v/a*z/\z} prints "z"
+ * (note that a*z _pattern_ is never globbed!)
+ */
+//TODO: fix expansion rules:
+ char *pattern, *repl, *t;
+ pattern = expand_pseudo_dquoted(exp_word);
+ if (!pattern)
+ pattern = xstrdup(exp_word);
+ debug_printf_varexp("pattern:'%s'->'%s'\n", exp_word, pattern);
+ *p++ = SPECIAL_VAR_SYMBOL;
+ exp_word = p;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+ *p = '\0';
+ repl = expand_pseudo_dquoted(exp_word);
+ debug_printf_varexp("repl:'%s'->'%s'\n", exp_word, repl);
+ /* HACK ALERT. We depend here on the fact that
+ * G.global_argv and results of utoa and get_local_var_value
+ * are actually in writable memory:
+ * replace_pattern momentarily stores NULs there. */
+ t = (char*)val;
+ to_be_freed = replace_pattern(t,
+ pattern,
+ (repl ? repl : exp_word),
+ exp_op);
+ if (to_be_freed) /* at least one replace happened */
+ val = to_be_freed;
+ free(pattern);
+ free(repl);
}
}
#endif
-#if ENABLE_HUSH_LOOPS
- if (rword == RES_FOR) { /* && pi->num_cmds - always == 1 */
- if (!for_lcur) {
- /* first loop through for */
-
- static const char encoded_dollar_at[] ALIGN1 = {
- SPECIAL_VAR_SYMBOL, '@' | 0x80, SPECIAL_VAR_SYMBOL, '\0'
- }; /* encoded representation of "$@" */
- static const char *const encoded_dollar_at_argv[] = {
- encoded_dollar_at, NULL
- }; /* argv list with one element: "$@" */
- char **vals;
-
- vals = (char**)encoded_dollar_at_argv;
- if (pi->next->res_word == RES_IN) {
- /* if no variable values after "in" we skip "for" */
- if (!pi->next->cmds[0].argv) {
- G.last_exitcode = rcode = EXIT_SUCCESS;
- debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n");
- break;
+ else if (exp_op == ':') {
+#if ENABLE_HUSH_BASH_COMPAT && ENABLE_SH_MATH_SUPPORT
+ /* It's ${var:N[:M]} bashism.
+ * Note that in encoded form it has TWO parts:
+ * var:N<SPECIAL_VAR_SYMBOL>M<SPECIAL_VAR_SYMBOL>
+ */
+ arith_t beg, len;
+ int errcode = 0;
+
+ beg = expand_and_evaluate_arith(exp_word, &errcode);
+ debug_printf_varexp("beg:'%s'=%lld\n", exp_word, (long long)beg);
+ *p++ = SPECIAL_VAR_SYMBOL;
+ exp_word = p;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+ *p = '\0';
+ len = expand_and_evaluate_arith(exp_word, &errcode);
+ debug_printf_varexp("len:'%s'=%lld\n", exp_word, (long long)len);
+
+ if (errcode >= 0 && len >= 0) { /* bash compat: len < 0 is illegal */
+ if (beg < 0) /* bash compat */
+ beg = 0;
+ debug_printf_varexp("from val:'%s'\n", val);
+ if (len == 0 || !val || beg >= strlen(val))
+ val = "";
+ else {
+ /* Paranoia. What if user entered 9999999999999
+ * which fits in arith_t but not int? */
+ if (len >= INT_MAX)
+ len = INT_MAX;
+ val = to_be_freed = xstrndup(val + beg, len);
+ }
+ debug_printf_varexp("val:'%s'\n", val);
+ } else
+#endif
+ {
+ die_if_script("malformed ${%s:...}", var);
+ val = "";
+ }
+ } else { /* one of "-=+?" */
+ /* Standard-mandated substitution ops:
+ * ${var?word} - indicate error if unset
+ * If var is unset, word (or a message indicating it is unset
+ * if word is null) is written to standard error
+ * and the shell exits with a non-zero exit status.
+ * Otherwise, the value of var is substituted.
+ * ${var-word} - use default value
+ * If var is unset, word is substituted.
+ * ${var=word} - assign and use default value
+ * If var is unset, word is assigned to var.
+ * In all cases, final value of var is substituted.
+ * ${var+word} - use alternative value
+ * If var is unset, null is substituted.
+ * Otherwise, word is substituted.
+ *
+ * Word is subjected to tilde expansion, parameter expansion,
+ * command substitution, and arithmetic expansion.
+ * If word is not needed, it is not expanded.
+ *
+ * Colon forms (${var:-word}, ${var:=word} etc) do the same,
+ * but also treat null var as if it is unset.
+ */
+ int use_word = (!val || ((exp_save == ':') && !val[0]));
+ if (exp_op == '+')
+ use_word = !use_word;
+ debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op,
+ (exp_save == ':') ? "true" : "false", use_word);
+ if (use_word) {
+ to_be_freed = expand_pseudo_dquoted(exp_word);
+ if (to_be_freed)
+ exp_word = to_be_freed;
+ if (exp_op == '?') {
+ /* mimic bash message */
+ die_if_script("%s: %s",
+ var,
+ exp_word[0] ? exp_word : "parameter null or not set"
+ );
+//TODO: how interactive bash aborts expansion mid-command?
+ } else {
+ val = exp_word;
+ }
+
+ if (exp_op == '=') {
+ /* ${var=[word]} or ${var:=[word]} */
+ if (isdigit(var[0]) || var[0] == '#') {
+ /* mimic bash message */
+ die_if_script("$%s: cannot assign in this way", var);
+ val = NULL;
+ } else {
+ char *new_var = xasprintf("%s=%s", var, val);
+ set_local_var(new_var, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
}
- vals = pi->next->cmds[0].argv;
- } /* else: "for var; do..." -> assume "$@" list */
- /* create list of variable values */
- debug_print_strings("for_list made from", vals);
- for_list = expand_strvec_to_strvec(vals);
- for_lcur = for_list;
- debug_print_strings("for_list", for_list);
+ }
}
- if (!*for_lcur) {
- /* "for" loop is over, clean up */
- free(for_list);
- for_list = NULL;
- for_lcur = NULL;
+ } /* one of "-=+?" */
+
+ *exp_saveptr = exp_save;
+ } /* if (exp_op) */
+
+ arg[0] = first_ch;
+
+ *pp = p;
+ *to_be_freed_pp = to_be_freed;
+ return val;
+}
+
+/* Expand all variable references in given string, adding words to list[]
+ * at n, n+1,... positions. Return updated n (so that list[n] is next one
+ * to be filled). This routine is extremely tricky: has to deal with
+ * variables/parameters with whitespace, $* and $@, and constructs like
+ * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
+static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
+{
+ /* or_mask is either 0 (normal case) or 0x80 -
+ * expansion of right-hand side of assignment == 1-element expand.
+ * It will also do no globbing, and thus we must not backslash-quote!
+ */
+ char ored_ch;
+ char *p;
+
+ ored_ch = 0;
+
+ debug_printf_expand("expand_vars_to_list: arg:'%s' or_mask:%x\n", arg, or_mask);
+ debug_print_list("expand_vars_to_list", output, n);
+ n = o_save_ptr(output, n);
+ debug_print_list("expand_vars_to_list[0]", output, n);
+
+ while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) {
+ char first_ch;
+ char *to_be_freed = NULL;
+ const char *val = NULL;
+#if ENABLE_HUSH_TICK
+ o_string subst_result = NULL_O_STRING;
+#endif
+#if ENABLE_SH_MATH_SUPPORT
+ char arith_buf[sizeof(arith_t)*3 + 2];
+#endif
+ o_addblock(output, arg, p - arg);
+ debug_print_list("expand_vars_to_list[1]", output, n);
+ arg = ++p;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+
+ first_ch = arg[0] | or_mask; /* forced to "quoted" if or_mask = 0x80 */
+ /* "$@" is special. Even if quoted, it can still
+ * expand to nothing (not even an empty string) */
+ if ((first_ch & 0x7f) != '@')
+ ored_ch |= first_ch;
+
+ switch (first_ch & 0x7f) {
+ /* Highest bit in first_ch indicates that var is double-quoted */
+ case '*':
+ case '@': {
+ int i;
+ if (!G.global_argv[1])
break;
+ i = 1;
+ ored_ch |= first_ch; /* do it for "$@" _now_, when we know it's not empty */
+ if (!(first_ch & 0x80)) { /* unquoted $* or $@ */
+ int sv = output->o_expflags;
+ /* unquoted var's contents should be globbed, so don't escape */
+ output->o_expflags &= ~EXP_FLAG_ESC_GLOB_CHARS;
+ while (G.global_argv[i]) {
+ n = expand_on_ifs(output, n, G.global_argv[i]);
+ debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1);
+ if (G.global_argv[i++][0] && G.global_argv[i]) {
+ /* this argv[] is not empty and not last:
+ * put terminating NUL, start new word */
+ o_addchr(output, '\0');
+ debug_print_list("expand_vars_to_list[2]", output, n);
+ n = o_save_ptr(output, n);
+ debug_print_list("expand_vars_to_list[3]", output, n);
+ }
+ }
+ output->o_expflags = sv;
+ } else
+ /* If or_mask is nonzero, we handle assignment 'a=....$@.....'
+ * and in this case should treat it like '$*' - see 'else...' below */
+ if (first_ch == ('@'|0x80) && !or_mask) { /* quoted $@ */
+ while (1) {
+ o_addQstr(output, G.global_argv[i]);
+ if (++i >= G.global_argc)
+ break;
+ o_addchr(output, '\0');
+ debug_print_list("expand_vars_to_list[4]", output, n);
+ n = o_save_ptr(output, n);
+ }
+ } else { /* quoted $*: add as one word */
+ while (1) {
+ o_addQstr(output, G.global_argv[i]);
+ if (!G.global_argv[++i])
+ break;
+ if (G.ifs[0])
+ o_addchr(output, G.ifs[0]);
+ }
}
- /* Insert next value from for_lcur */
- /* note: *for_lcur already has quotes removed, $var expanded, etc */
- set_local_var(xasprintf("%s=%s", pi->cmds[0].argv[0], *for_lcur++), /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
- continue;
- }
- if (rword == RES_IN) {
- continue; /* "for v IN list;..." - "in" has no cmds anyway */
- }
- if (rword == RES_DONE) {
- continue; /* "done" has no cmds too */
+ break;
}
+ case SPECIAL_VAR_SYMBOL: /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */
+ /* "Empty variable", used to make "" etc to not disappear */
+ arg++;
+ ored_ch = 0x80;
+ break;
+#if ENABLE_HUSH_TICK
+ case '`': /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */
+ *p = '\0';
+ arg++;
+ /* Can't just stuff it into output o_string,
+ * expanded result may need to be globbed
+ * and $IFS-splitted */
+ debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch);
+ G.last_exitcode = process_command_subs(&subst_result, arg);
+ debug_printf_subst("SUBST RES:%d '%s'\n", G.last_exitcode, subst_result.data);
+ val = subst_result.data;
+ goto store_val;
#endif
-#if ENABLE_HUSH_CASE
- if (rword == RES_CASE) {
- case_word = expand_strvec_to_string(pi->cmds->argv);
- continue;
- }
- if (rword == RES_MATCH) {
- char **argv;
+#if ENABLE_SH_MATH_SUPPORT
+ case '+': { /* <SPECIAL_VAR_SYMBOL>+cmd<SPECIAL_VAR_SYMBOL> */
+ arith_t res;
+ int errcode;
- if (!case_word) /* "case ... matched_word) ... WORD)": we executed selected branch, stop */
- break;
- /* all prev words didn't match, does this one match? */
- argv = pi->cmds->argv;
- while (*argv) {
- char *pattern = expand_string_to_string(*argv);
- /* TODO: which FNM_xxx flags to use? */
- cond_code = (fnmatch(pattern, case_word, /*flags:*/ 0) != 0);
- free(pattern);
- if (cond_code == 0) { /* match! we will execute this branch */
- free(case_word); /* make future "word)" stop */
- case_word = NULL;
+ arg++; /* skip '+' */
+ *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
+ debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch);
+ res = expand_and_evaluate_arith(arg, &errcode);
+
+ if (errcode < 0) {
+ const char *msg = "error in arithmetic";
+ switch (errcode) {
+ case -3:
+ msg = "exponent less than 0";
+ break;
+ case -2:
+ msg = "divide by 0";
+ break;
+ case -5:
+ msg = "expression recursion loop detected";
break;
}
- argv++;
+ die_if_script(msg);
}
- continue;
- }
- if (rword == RES_CASE_BODY) { /* inside of a case branch */
- if (cond_code != 0)
- continue; /* not matched yet, skip this pipe */
+ debug_printf_subst("ARITH RES '"arith_t_fmt"'\n", res);
+ sprintf(arith_buf, arith_t_fmt, res);
+ val = arith_buf;
+ break;
}
#endif
- /* Just pressing <enter> in shell should check for jobs.
- * OTOH, in non-interactive shell this is useless
- * and only leads to extra job checks */
- if (pi->num_cmds == 0) {
- if (G_interactive_fd)
- goto check_jobs_and_continue;
- continue;
+ default:
+ val = expand_one_var(&to_be_freed, arg, &p, first_ch);
+ IF_HUSH_TICK(store_val:)
+ if (!(first_ch & 0x80)) { /* unquoted $VAR */
+ debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val,
+ !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ if (val && val[0]) {
+ /* unquoted var's contents should be globbed, so don't escape */
+ int sv = output->o_expflags;
+ output->o_expflags &= ~EXP_FLAG_ESC_GLOB_CHARS;
+ n = expand_on_ifs(output, n, val);
+ val = NULL;
+ output->o_expflags = sv;
+ }
+ } else { /* quoted $VAR, val will be appended below */
+ debug_printf_expand("quoted '%s', output->o_escape:%d\n", val,
+ !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ }
+ break;
+
+ } /* switch (char after <SPECIAL_VAR_SYMBOL>) */
+
+ if (val && val[0]) {
+ o_addQstr(output, val);
}
+ free(to_be_freed);
+ /* Do the check to avoid writing to a const string */
+ if (*p != SPECIAL_VAR_SYMBOL)
+ *p = SPECIAL_VAR_SYMBOL;
- /* After analyzing all keywords and conditions, we decided
- * to execute this pipe. NB: have to do checkjobs(NULL)
- * after run_pipe to collect any background children,
- * even if list execution is to be stopped. */
- debug_printf_exec(": run_pipe with %d members\n", pi->num_cmds);
- {
- int r;
-#if ENABLE_HUSH_LOOPS
- G.flag_break_continue = 0;
-#endif
- rcode = r = run_pipe(pi); /* NB: rcode is a smallint */
- if (r != -1) {
- /* We ran a builtin, function, or group.
- * rcode is already known
- * and we don't need to wait for anything. */
- G.last_exitcode = rcode;
- debug_printf_exec(": builtin/func exitcode %d\n", rcode);
- check_and_run_traps(0);
-#if ENABLE_HUSH_LOOPS
- /* Was it "break" or "continue"? */
- if (G.flag_break_continue) {
- smallint fbc = G.flag_break_continue;
- /* We might fall into outer *loop*,
- * don't want to break it too */
- if (loop_top) {
- G.depth_break_continue--;
- if (G.depth_break_continue == 0)
- G.flag_break_continue = 0;
- /* else: e.g. "continue 2" should *break* once, *then* continue */
- } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */
- if (G.depth_break_continue != 0 || fbc == BC_BREAK)
- goto check_jobs_and_break;
- /* "continue": simulate end of loop */
- rword = RES_DONE;
- continue;
- }
+#if ENABLE_HUSH_TICK
+ o_free(&subst_result);
#endif
-#if ENABLE_HUSH_FUNCTIONS
- if (G.flag_return_in_progress == 1) {
- /* same as "goto check_jobs_and_break" */
- checkjobs(NULL);
- break;
- }
-#endif
- } else if (pi->followup == PIPE_BG) {
- /* What does bash do with attempts to background builtins? */
- /* even bash 3.2 doesn't do that well with nested bg:
- * try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
- * I'm NOT treating inner &'s as jobs */
- check_and_run_traps(0);
-#if ENABLE_HUSH_JOB
- if (G.run_list_level == 1)
- insert_bg_job(pi);
-#endif
- G.last_exitcode = rcode = EXIT_SUCCESS;
- debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n");
- } else {
-#if ENABLE_HUSH_JOB
- if (G.run_list_level == 1 && G_interactive_fd) {
- /* Waits for completion, then fg's main shell */
- rcode = checkjobs_and_fg_shell(pi);
- debug_printf_exec(": checkjobs_and_fg_shell exitcode %d\n", rcode);
- check_and_run_traps(0);
- } else
-#endif
- { /* This one just waits for completion */
- rcode = checkjobs(pi);
- debug_printf_exec(": checkjobs exitcode %d\n", rcode);
- check_and_run_traps(0);
- }
- G.last_exitcode = rcode;
- }
- }
+ arg = ++p;
+ } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */
- /* Analyze how result affects subsequent commands */
-#if ENABLE_HUSH_IF
- if (rword == RES_IF || rword == RES_ELIF)
- cond_code = rcode;
+ if (arg[0]) {
+ debug_print_list("expand_vars_to_list[a]", output, n);
+ /* this part is literal, and it was already pre-quoted
+ * if needed (much earlier), do not use o_addQstr here! */
+ o_addstr_with_NUL(output, arg);
+ debug_print_list("expand_vars_to_list[b]", output, n);
+ } else if (output->length == o_get_last_ptr(output, n) /* expansion is empty */
+ && !(ored_ch & 0x80) /* and all vars were not quoted. */
+ ) {
+ n--;
+ /* allow to reuse list[n] later without re-growth */
+ output->has_empty_slot = 1;
+ } else {
+ o_addchr(output, '\0');
+ }
+
+ return n;
+}
+
+static char **expand_variables(char **argv, unsigned or_mask)
+{
+ int n;
+ char **list;
+ o_string output = NULL_O_STRING;
+
+ output.o_expflags = or_mask;
+
+ n = 0;
+ while (*argv) {
+ n = expand_vars_to_list(&output, n, *argv, (unsigned char)or_mask);
+ argv++;
+ }
+ debug_print_list("expand_variables", &output, n);
+
+ /* output.data (malloced in one block) gets returned in "list" */
+ list = o_finalize_list(&output, n);
+ debug_print_strings("expand_variables[1]", list);
+ return list;
+}
+
+static char **expand_strvec_to_strvec(char **argv)
+{
+ return expand_variables(argv, EXP_FLAG_GLOB | EXP_FLAG_ESC_GLOB_CHARS);
+}
+
+#if ENABLE_HUSH_BASH_COMPAT
+static char **expand_strvec_to_strvec_singleword_noglob(char **argv)
+{
+ return expand_variables(argv, EXP_FLAG_SINGLEWORD);
+}
#endif
-#if ENABLE_HUSH_LOOPS
- /* Beware of "while false; true; do ..."! */
- if (pi->next && pi->next->res_word == RES_DO) {
- if (rword == RES_WHILE) {
- if (rcode) {
- /* "while false; do...done" - exitcode 0 */
- G.last_exitcode = rcode = EXIT_SUCCESS;
- debug_printf_exec(": while expr is false: breaking (exitcode:EXIT_SUCCESS)\n");
- goto check_jobs_and_break;
- }
- }
- if (rword == RES_UNTIL) {
- if (!rcode) {
- debug_printf_exec(": until expr is true: breaking\n");
- check_jobs_and_break:
- checkjobs(NULL);
- break;
- }
- }
+
+/* Used for expansion of right hand of assignments,
+ * $((...)), heredocs, variable espansion parts.
+ *
+ * NB: should NOT do globbing!
+ * "export v=/bin/c*; env | grep ^v=" outputs "v=/bin/c*"
+ */
+static char *expand_string_to_string(const char *str)
+{
+ char *argv[2], **list;
+
+ /* This is generally an optimization, but it also
+ * handles "", which otherwise trips over !list[0] check below.
+ * (is this ever happens that we actually get str="" here?)
+ */
+ if (!strchr(str, SPECIAL_VAR_SYMBOL) && !strchr(str, '\\')) {
+ //TODO: Can use on strings with \ too, just unbackslash() them?
+ debug_printf_expand("string_to_string(fast)='%s'\n", str);
+ return xstrdup(str);
+ }
+
+ argv[0] = (char*)str;
+ argv[1] = NULL;
+ list = expand_variables(argv, EXP_FLAG_ESC_GLOB_CHARS | EXP_FLAG_SINGLEWORD);
+ if (HUSH_DEBUG)
+ if (!list[0] || list[1])
+ bb_error_msg_and_die("BUG in varexp2");
+ /* actually, just move string 2*sizeof(char*) bytes back */
+ overlapping_strcpy((char*)list, list[0]);
+ unbackslash((char*)list);
+ debug_printf_expand("string_to_string='%s'\n", (char*)list);
+ return (char*)list;
+}
+
+/* Used for "eval" builtin */
+static char* expand_strvec_to_string(char **argv)
+{
+ char **list;
+
+ list = expand_variables(argv, EXP_FLAG_SINGLEWORD);
+ /* Convert all NULs to spaces */
+ if (list[0]) {
+ int n = 1;
+ while (list[n]) {
+ if (HUSH_DEBUG)
+ if (list[n-1] + strlen(list[n-1]) + 1 != list[n])
+ bb_error_msg_and_die("BUG in varexp3");
+ /* bash uses ' ' regardless of $IFS contents */
+ list[n][-1] = ' ';
+ n++;
}
-#endif
+ }
+ overlapping_strcpy((char*)list, list[0]);
+ debug_printf_expand("strvec_to_string='%s'\n", (char*)list);
+ return (char*)list;
+}
- check_jobs_and_continue:
- checkjobs(NULL);
- } /* for (pi) */
+static char **expand_assignments(char **argv, int count)
+{
+ int i;
+ char **p;
-#if ENABLE_HUSH_JOB
- G.run_list_level--;
-#endif
-#if ENABLE_HUSH_LOOPS
- if (loop_top)
- G.depth_of_loop--;
- free(for_list);
-#endif
-#if ENABLE_HUSH_CASE
- free(case_word);
-#endif
- debug_leave();
- debug_printf_exec("run_list lvl %d return %d\n", G.run_list_level + 1, rcode);
- return rcode;
+ G.expanded_assignments = p = NULL;
+ /* Expand assignments into one string each */
+ for (i = 0; i < count; i++) {
+ G.expanded_assignments = p = add_string_to_strings(p, expand_string_to_string(argv[i]));
+ }
+ G.expanded_assignments = NULL;
+ return p;
}
-/* Select which version we will use */
-static int run_and_free_list(struct pipe *pi)
+
+#if BB_MMU
+/* never called */
+void re_execute_shell(char ***to_free, const char *s,
+ char *g_argv0, char **g_argv,
+ char **builtin_argv) NORETURN;
+
+static void reset_traps_to_defaults(void)
{
- int rcode = 0;
- debug_printf_exec("run_and_free_list entered\n");
- if (!G.fake_mode) {
- debug_printf_exec(": run_list: 1st pipe with %d cmds\n", pi->num_cmds);
- rcode = run_list(pi);
+ /* This function is always called in a child shell
+ * after fork (not vfork, NOMMU doesn't use this function).
+ */
+ unsigned sig;
+ unsigned mask;
+
+ /* Child shells are not interactive.
+ * SIGTTIN/SIGTTOU/SIGTSTP should not have special handling.
+ * Testcase: (while :; do :; done) + ^Z should background.
+ * Same goes for SIGTERM, SIGHUP, SIGINT.
+ */
+ if (!G.traps && !(G.non_DFL_mask & SPECIAL_INTERACTIVE_SIGS))
+ return; /* already no traps and no SPECIAL_INTERACTIVE_SIGS */
+
+ /* Switching off SPECIAL_INTERACTIVE_SIGS.
+ * Stupid. It can be done with *single* &= op, but we can't use
+ * the fact that G.blocked_set is implemented as a bitmask
+ * in libc... */
+ mask = (SPECIAL_INTERACTIVE_SIGS >> 1);
+ sig = 1;
+ while (1) {
+ if (mask & 1) {
+ /* Careful. Only if no trap or trap is not "" */
+ if (!G.traps || !G.traps[sig] || G.traps[sig][0])
+ sigdelset(&G.blocked_set, sig);
+ }
+ mask >>= 1;
+ if (!mask)
+ break;
+ sig++;
+ }
+ /* Our homegrown sig mask is saner to work with :) */
+ G.non_DFL_mask &= ~SPECIAL_INTERACTIVE_SIGS;
+
+ /* Resetting all traps to default except empty ones */
+ mask = G.non_DFL_mask;
+ if (G.traps) for (sig = 0; sig < NSIG; sig++, mask >>= 1) {
+ if (!G.traps[sig] || !G.traps[sig][0])
+ continue;
+ free(G.traps[sig]);
+ G.traps[sig] = NULL;
+ /* There is no signal for 0 (EXIT) */
+ if (sig == 0)
+ continue;
+ /* There was a trap handler, we just removed it.
+ * But if sig still has non-DFL handling,
+ * we should not unblock the sig. */
+ if (mask & 1)
+ continue;
+ sigdelset(&G.blocked_set, sig);
+ }
+ sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
+}
+
+#else /* !BB_MMU */
+
+static void re_execute_shell(char ***to_free, const char *s,
+ char *g_argv0, char **g_argv,
+ char **builtin_argv) NORETURN;
+static void re_execute_shell(char ***to_free, const char *s,
+ char *g_argv0, char **g_argv,
+ char **builtin_argv)
+{
+# define NOMMU_HACK_FMT ("-$%x:%x:%x:%x:%x:%llx" IF_HUSH_LOOPS(":%x"))
+ /* delims + 2 * (number of bytes in printed hex numbers) */
+ char param_buf[sizeof(NOMMU_HACK_FMT) + 2 * (sizeof(int)*6 + sizeof(long long)*1)];
+ char *heredoc_argv[4];
+ struct variable *cur;
+# if ENABLE_HUSH_FUNCTIONS
+ struct function *funcp;
+# endif
+ char **argv, **pp;
+ unsigned cnt;
+ unsigned long long empty_trap_mask;
+
+ if (!g_argv0) { /* heredoc */
+ argv = heredoc_argv;
+ argv[0] = (char *) G.argv0_for_re_execing;
+ argv[1] = (char *) "-<";
+ argv[2] = (char *) s;
+ argv[3] = NULL;
+ pp = &argv[3]; /* used as pointer to empty environment */
+ goto do_exec;
+ }
+
+ cnt = 0;
+ pp = builtin_argv;
+ if (pp) while (*pp++)
+ cnt++;
+
+ empty_trap_mask = 0;
+ if (G.traps) {
+ int sig;
+ for (sig = 1; sig < NSIG; sig++) {
+ if (G.traps[sig] && !G.traps[sig][0])
+ empty_trap_mask |= 1LL << sig;
+ }
+ }
+
+ sprintf(param_buf, NOMMU_HACK_FMT
+ , (unsigned) G.root_pid
+ , (unsigned) G.root_ppid
+ , (unsigned) G.last_bg_pid
+ , (unsigned) G.last_exitcode
+ , cnt
+ , empty_trap_mask
+ IF_HUSH_LOOPS(, G.depth_of_loop)
+ );
+# undef NOMMU_HACK_FMT
+ /* 1:hush 2:-$<pid>:<pid>:<exitcode>:<etc...> <vars...> <funcs...>
+ * 3:-c 4:<cmd> 5:<arg0> <argN...> 6:NULL
+ */
+ cnt += 6;
+ for (cur = G.top_var; cur; cur = cur->next) {
+ if (!cur->flg_export || cur->flg_read_only)
+ cnt += 2;
+ }
+# if ENABLE_HUSH_FUNCTIONS
+ for (funcp = G.top_func; funcp; funcp = funcp->next)
+ cnt += 3;
+# endif
+ pp = g_argv;
+ while (*pp++)
+ cnt++;
+ *to_free = argv = pp = xzalloc(sizeof(argv[0]) * cnt);
+ *pp++ = (char *) G.argv0_for_re_execing;
+ *pp++ = param_buf;
+ for (cur = G.top_var; cur; cur = cur->next) {
+ if (strcmp(cur->varstr, hush_version_str) == 0)
+ continue;
+ if (cur->flg_read_only) {
+ *pp++ = (char *) "-R";
+ *pp++ = cur->varstr;
+ } else if (!cur->flg_export) {
+ *pp++ = (char *) "-V";
+ *pp++ = cur->varstr;
+ }
+ }
+# if ENABLE_HUSH_FUNCTIONS
+ for (funcp = G.top_func; funcp; funcp = funcp->next) {
+ *pp++ = (char *) "-F";
+ *pp++ = funcp->name;
+ *pp++ = funcp->body_as_string;
+ }
+# endif
+ /* We can pass activated traps here. Say, -Tnn:trap_string
+ *
+ * However, POSIX says that subshells reset signals with traps
+ * to SIG_DFL.
+ * I tested bash-3.2 and it not only does that with true subshells
+ * of the form ( list ), but with any forked children shells.
+ * I set trap "echo W" WINCH; and then tried:
+ *
+ * { echo 1; sleep 20; echo 2; } &
+ * while true; do echo 1; sleep 20; echo 2; break; done &
+ * true | { echo 1; sleep 20; echo 2; } | cat
+ *
+ * In all these cases sending SIGWINCH to the child shell
+ * did not run the trap. If I add trap "echo V" WINCH;
+ * _inside_ group (just before echo 1), it works.
+ *
+ * I conclude it means we don't need to pass active traps here.
+ * Even if we would use signal handlers instead of signal masking
+ * in order to implement trap handling,
+ * exec syscall below resets signals to SIG_DFL for us.
+ */
+ *pp++ = (char *) "-c";
+ *pp++ = (char *) s;
+ if (builtin_argv) {
+ while (*++builtin_argv)
+ *pp++ = *builtin_argv;
+ *pp++ = (char *) "";
}
- /* free_pipe_list has the side effect of clearing memory.
- * In the long run that function can be merged with run_list,
- * but doing that now would hobble the debugging effort. */
- free_pipe_list(pi);
- debug_printf_exec("run_and_free_list return %d\n", rcode);
- return rcode;
+ *pp++ = g_argv0;
+ while (*g_argv)
+ *pp++ = *g_argv++;
+ /* *pp = NULL; - is already there */
+ pp = environ;
+
+ do_exec:
+ debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s);
+ sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
+ execve(bb_busybox_exec_path, argv, pp);
+ /* Fallback. Useful for init=/bin/hush usage etc */
+ if (argv[0][0] == '/')
+ execve(argv[0], argv, pp);
+ xfunc_error_retval = 127;
+ bb_error_msg_and_die("can't re-execute the shell");
}
+#endif /* !BB_MMU */
-static struct pipe *new_pipe(void)
-{
- struct pipe *pi;
- pi = xzalloc(sizeof(struct pipe));
- /*pi->followup = 0; - deliberately invalid value */
- /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */
- return pi;
-}
+static int run_and_free_list(struct pipe *pi);
-/* Command (member of a pipe) is complete, or we start a new pipe
- * if ctx->command is NULL.
- * No errors possible here.
+/* Executing from string: eval, sh -c '...'
+ * or from file: /etc/profile, . file, sh <script>, sh (intereactive)
+ * end_trigger controls how often we stop parsing
+ * NUL: parse all, execute, return
+ * ';': parse till ';' or newline, execute, repeat till EOF
*/
-static int done_command(struct parse_context *ctx)
+static void parse_and_run_stream(struct in_str *inp, int end_trigger)
{
- /* The command is really already in the pipe structure, so
- * advance the pipe counter and make a new, null command. */
- struct pipe *pi = ctx->pipe;
- struct command *command = ctx->command;
+ /* Why we need empty flag?
+ * An obscure corner case "false; ``; echo $?":
+ * empty command in `` should still set $? to 0.
+ * But we can't just set $? to 0 at the start,
+ * this breaks "false; echo `echo $?`" case.
+ */
+ bool empty = 1;
+ while (1) {
+ struct pipe *pipe_list;
- if (command) {
- if (IS_NULL_CMD(command)) {
- debug_printf_parse("done_command: skipping null cmd, num_cmds=%d\n", pi->num_cmds);
- goto clear_and_ret;
+ pipe_list = parse_stream(NULL, inp, end_trigger);
+ if (!pipe_list) { /* EOF */
+ if (empty)
+ G.last_exitcode = 0;
+ break;
}
- pi->num_cmds++;
- debug_printf_parse("done_command: ++num_cmds=%d\n", pi->num_cmds);
- //debug_print_tree(ctx->list_head, 20);
- } else {
- debug_printf_parse("done_command: initializing, num_cmds=%d\n", pi->num_cmds);
+ debug_print_tree(pipe_list, 0);
+ debug_printf_exec("parse_and_run_stream: run_and_free_list\n");
+ run_and_free_list(pipe_list);
+ empty = 0;
}
-
- /* Only real trickiness here is that the uncommitted
- * command structure is not counted in pi->num_cmds. */
- pi->cmds = xrealloc(pi->cmds, sizeof(*pi->cmds) * (pi->num_cmds+1));
- ctx->command = command = &pi->cmds[pi->num_cmds];
- clear_and_ret:
- memset(command, 0, sizeof(*command));
- return pi->num_cmds; /* used only for 0/nonzero check */
}
-static void done_pipe(struct parse_context *ctx, pipe_style type)
+static void parse_and_run_string(const char *s)
{
- int not_null;
-
- debug_printf_parse("done_pipe entered, followup %d\n", type);
- /* Close previous command */
- not_null = done_command(ctx);
- ctx->pipe->followup = type;
-#if HAS_KEYWORDS
- ctx->pipe->pi_inverted = ctx->ctx_inverted;
- ctx->ctx_inverted = 0;
- ctx->pipe->res_word = ctx->ctx_res_w;
-#endif
-
- /* Without this check, even just <enter> on command line generates
- * tree of three NOPs (!). Which is harmless but annoying.
- * IOW: it is safe to do it unconditionally. */
- if (not_null
-#if ENABLE_HUSH_IF
- || ctx->ctx_res_w == RES_FI
-#endif
-#if ENABLE_HUSH_LOOPS
- || ctx->ctx_res_w == RES_DONE
- || ctx->ctx_res_w == RES_FOR
- || ctx->ctx_res_w == RES_IN
-#endif
-#if ENABLE_HUSH_CASE
- || ctx->ctx_res_w == RES_ESAC
-#endif
- ) {
- struct pipe *new_p;
- debug_printf_parse("done_pipe: adding new pipe: "
- "not_null:%d ctx->ctx_res_w:%d\n",
- not_null, ctx->ctx_res_w);
- new_p = new_pipe();
- ctx->pipe->next = new_p;
- ctx->pipe = new_p;
- /* RES_THEN, RES_DO etc are "sticky" -
- * they remain set for pipes inside if/while.
- * This is used to control execution.
- * RES_FOR and RES_IN are NOT sticky (needed to support
- * cases where variable or value happens to match a keyword):
- */
-#if ENABLE_HUSH_LOOPS
- if (ctx->ctx_res_w == RES_FOR
- || ctx->ctx_res_w == RES_IN)
- ctx->ctx_res_w = RES_NONE;
-#endif
-#if ENABLE_HUSH_CASE
- if (ctx->ctx_res_w == RES_MATCH)
- ctx->ctx_res_w = RES_CASE_BODY;
- if (ctx->ctx_res_w == RES_CASE)
- ctx->ctx_res_w = RES_CASE_IN;
-#endif
- ctx->command = NULL; /* trick done_command below */
- /* Create the memory for command, roughly:
- * ctx->pipe->cmds = new struct command;
- * ctx->command = &ctx->pipe->cmds[0];
- */
- done_command(ctx);
- //debug_print_tree(ctx->list_head, 10);
- }
- debug_printf_parse("done_pipe return\n");
+ struct in_str input;
+ setup_string_in_str(&input, s);
+ parse_and_run_stream(&input, '\0');
}
-static void initialize_context(struct parse_context *ctx)
+static void parse_and_run_file(FILE *f)
{
- memset(ctx, 0, sizeof(*ctx));
- ctx->pipe = ctx->list_head = new_pipe();
- /* Create the memory for command, roughly:
- * ctx->pipe->cmds = new struct command;
- * ctx->command = &ctx->pipe->cmds[0];
- */
- done_command(ctx);
+ struct in_str input;
+ setup_file_in_str(&input, f);
+ parse_and_run_stream(&input, ';');
}
-/* If a reserved word is found and processed, parse context is modified
- * and 1 is returned.
- */
-#if HAS_KEYWORDS
-struct reserved_combo {
- char literal[6];
- unsigned char res;
- unsigned char assignment_flag;
- int flag;
-};
-enum {
- FLAG_END = (1 << RES_NONE ),
-# if ENABLE_HUSH_IF
- FLAG_IF = (1 << RES_IF ),
- FLAG_THEN = (1 << RES_THEN ),
- FLAG_ELIF = (1 << RES_ELIF ),
- FLAG_ELSE = (1 << RES_ELSE ),
- FLAG_FI = (1 << RES_FI ),
-# endif
-# if ENABLE_HUSH_LOOPS
- FLAG_FOR = (1 << RES_FOR ),
- FLAG_WHILE = (1 << RES_WHILE),
- FLAG_UNTIL = (1 << RES_UNTIL),
- FLAG_DO = (1 << RES_DO ),
- FLAG_DONE = (1 << RES_DONE ),
- FLAG_IN = (1 << RES_IN ),
-# endif
-# if ENABLE_HUSH_CASE
- FLAG_MATCH = (1 << RES_MATCH),
- FLAG_ESAC = (1 << RES_ESAC ),
+#if ENABLE_HUSH_TICK
+static FILE *generate_stream_from_string(const char *s, pid_t *pid_p)
+{
+ pid_t pid;
+ int channel[2];
+# if !BB_MMU
+ char **to_free = NULL;
# endif
- FLAG_START = (1 << RES_XXXX ),
-};
-static const struct reserved_combo* match_reserved_word(o_string *word)
-{
- /* Mostly a list of accepted follow-up reserved words.
- * FLAG_END means we are done with the sequence, and are ready
- * to turn the compound list into a command.
- * FLAG_START means the word must start a new compound list.
+ xpipe(channel);
+ pid = BB_MMU ? xfork() : xvfork();
+ if (pid == 0) { /* child */
+ disable_restore_tty_pgrp_on_exit();
+ /* Process substitution is not considered to be usual
+ * 'command execution'.
+ * SUSv3 says ctrl-Z should be ignored, ctrl-C should not.
+ */
+ bb_signals(0
+ + (1 << SIGTSTP)
+ + (1 << SIGTTIN)
+ + (1 << SIGTTOU)
+ , SIG_IGN);
+ CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
+ close(channel[0]); /* NB: close _first_, then move fd! */
+ xmove_fd(channel[1], 1);
+ /* Prevent it from trying to handle ctrl-z etc */
+ IF_HUSH_JOB(G.run_list_level = 1;)
+ /* Awful hack for `trap` or $(trap).
+ *
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/trap.html
+ * contains an example where "trap" is executed in a subshell:
+ *
+ * save_traps=$(trap)
+ * ...
+ * eval "$save_traps"
+ *
+ * Standard does not say that "trap" in subshell shall print
+ * parent shell's traps. It only says that its output
+ * must have suitable form, but then, in the above example
+ * (which is not supposed to be normative), it implies that.
+ *
+ * bash (and probably other shell) does implement it
+ * (traps are reset to defaults, but "trap" still shows them),
+ * but as a result, "trap" logic is hopelessly messed up:
+ *
+ * # trap
+ * trap -- 'echo Ho' SIGWINCH <--- we have a handler
+ * # (trap) <--- trap is in subshell - no output (correct, traps are reset)
+ * # true | trap <--- trap is in subshell - no output (ditto)
+ * # echo `true | trap` <--- in subshell - output (but traps are reset!)
+ * trap -- 'echo Ho' SIGWINCH
+ * # echo `(trap)` <--- in subshell in subshell - output
+ * trap -- 'echo Ho' SIGWINCH
+ * # echo `true | (trap)` <--- in subshell in subshell in subshell - output!
+ * trap -- 'echo Ho' SIGWINCH
+ *
+ * The rules when to forget and when to not forget traps
+ * get really complex and nonsensical.
+ *
+ * Our solution: ONLY bare $(trap) or `trap` is special.
+ */
+ s = skip_whitespace(s);
+ if (strncmp(s, "trap", 4) == 0
+ && skip_whitespace(s + 4)[0] == '\0'
+ ) {
+ static const char *const argv[] = { NULL, NULL };
+ builtin_trap((char**)argv);
+ exit(0); /* not _exit() - we need to fflush */
+ }
+# if BB_MMU
+ reset_traps_to_defaults();
+ parse_and_run_string(s);
+ _exit(G.last_exitcode);
+# else
+ /* We re-execute after vfork on NOMMU. This makes this script safe:
+ * yes "0123456789012345678901234567890" | dd bs=32 count=64k >BIG
+ * huge=`cat BIG` # was blocking here forever
+ * echo OK
*/
- static const struct reserved_combo reserved_list[] = {
-# if ENABLE_HUSH_IF
- { "!", RES_NONE, NOT_ASSIGNMENT , 0 },
- { "if", RES_IF, WORD_IS_KEYWORD, FLAG_THEN | FLAG_START },
- { "then", RES_THEN, WORD_IS_KEYWORD, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
- { "elif", RES_ELIF, WORD_IS_KEYWORD, FLAG_THEN },
- { "else", RES_ELSE, WORD_IS_KEYWORD, FLAG_FI },
- { "fi", RES_FI, NOT_ASSIGNMENT , FLAG_END },
+ re_execute_shell(&to_free,
+ s,
+ G.global_argv[0],
+ G.global_argv + 1,
+ NULL);
# endif
-# if ENABLE_HUSH_LOOPS
- { "for", RES_FOR, NOT_ASSIGNMENT , FLAG_IN | FLAG_DO | FLAG_START },
- { "while", RES_WHILE, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
- { "until", RES_UNTIL, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
- { "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO },
- { "do", RES_DO, WORD_IS_KEYWORD, FLAG_DONE },
- { "done", RES_DONE, NOT_ASSIGNMENT , FLAG_END },
+ }
+
+ /* parent */
+ *pid_p = pid;
+# if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] fork in generate_stream_from_string:"
+// " G.count_SIGCHLD:%d G.handled_SIGCHLD:%d",
+// getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
# endif
-# if ENABLE_HUSH_CASE
- { "case", RES_CASE, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_START },
- { "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END },
+ enable_restore_tty_pgrp_on_exit();
+# if !BB_MMU
+ free(to_free);
# endif
- };
- const struct reserved_combo *r;
-
- for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) {
- if (strcmp(word->data, r->literal) == 0)
- return r;
- }
- return NULL;
+ close(channel[1]);
+ close_on_exec_on(channel[0]);
+ return xfdopen_for_read(channel[0]);
}
-/* Return 0: not a keyword, 1: keyword
- */
-static int reserved_word(o_string *word, struct parse_context *ctx)
+
+/* Return code is exit status of the process that is run. */
+static int process_command_subs(o_string *dest, const char *s)
{
-# if ENABLE_HUSH_CASE
- static const struct reserved_combo reserved_match = {
- "", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC
- };
-# endif
- const struct reserved_combo *r;
+ FILE *fp;
+ struct in_str pipe_str;
+ pid_t pid;
+ int status, ch, eol_cnt;
- if (word->o_quoted)
- return 0;
- r = match_reserved_word(word);
- if (!r)
- return 0;
+ fp = generate_stream_from_string(s, &pid);
- debug_printf("found reserved word %s, res %d\n", r->literal, r->res);
-# if ENABLE_HUSH_CASE
- if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE_IN) {
- /* "case word IN ..." - IN part starts first MATCH part */
- r = &reserved_match;
- } else
-# endif
- if (r->flag == 0) { /* '!' */
- if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */
- syntax_error("! ! command");
- ctx->ctx_res_w = RES_SNTX;
+ /* Now send results of command back into original context */
+ setup_file_in_str(&pipe_str, fp);
+ eol_cnt = 0;
+ while ((ch = i_getch(&pipe_str)) != EOF) {
+ if (ch == '\n') {
+ eol_cnt++;
+ continue;
}
- ctx->ctx_inverted = 1;
- return 1;
+ while (eol_cnt) {
+ o_addchr(dest, '\n');
+ eol_cnt--;
+ }
+ o_addQchr(dest, ch);
}
- if (r->flag & FLAG_START) {
- struct parse_context *old;
- old = xmalloc(sizeof(*old));
- debug_printf_parse("push stack %p\n", old);
- *old = *ctx; /* physical copy */
- initialize_context(ctx);
- ctx->stack = old;
- } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) {
- syntax_error_at(word->data);
- ctx->ctx_res_w = RES_SNTX;
- return 1;
- } else {
- /* "{...} fi" is ok. "{...} if" is not
- * Example:
- * if { echo foo; } then { echo bar; } fi */
- if (ctx->command->group)
- done_pipe(ctx, PIPE_SEQ);
- }
+ debug_printf("done reading from `cmd` pipe, closing it\n");
+ fclose(fp);
+ /* We need to extract exitcode. Test case
+ * "true; echo `sleep 1; false` $?"
+ * should print 1 */
+ safe_waitpid(pid, &status, 0);
+ debug_printf("child exited. returning its exitcode:%d\n", WEXITSTATUS(status));
+ return WEXITSTATUS(status);
+}
+#endif /* ENABLE_HUSH_TICK */
- ctx->ctx_res_w = r->res;
- ctx->old_flag = r->flag;
- word->o_assignment = r->assignment_flag;
- if (ctx->old_flag & FLAG_END) {
- struct parse_context *old;
+static void setup_heredoc(struct redir_struct *redir)
+{
+ struct fd_pair pair;
+ pid_t pid;
+ int len, written;
+ /* the _body_ of heredoc (misleading field name) */
+ const char *heredoc = redir->rd_filename;
+ char *expanded;
+#if !BB_MMU
+ char **to_free;
+#endif
- done_pipe(ctx, PIPE_SEQ);
- debug_printf_parse("pop stack %p\n", ctx->stack);
- old = ctx->stack;
- old->command->group = ctx->list_head;
- old->command->cmd_type = CMD_NORMAL;
-# if !BB_MMU
- o_addstr(&old->as_string, ctx->as_string.data);
- o_free_unsafe(&ctx->as_string);
- old->command->group_as_string = xstrdup(old->as_string.data);
- debug_printf_parse("pop, remembering as:'%s'\n",
- old->command->group_as_string);
-# endif
- *ctx = *old; /* physical copy */
- free(old);
+ expanded = NULL;
+ if (!(redir->rd_dup & HEREDOC_QUOTED)) {
+ expanded = expand_pseudo_dquoted(heredoc);
+ if (expanded)
+ heredoc = expanded;
}
- return 1;
-}
-#endif /* HAS_KEYWORDS */
+ len = strlen(heredoc);
-/* Word is complete, look at it and update parsing context.
- * Normal return is 0. Syntax errors return 1.
- * Note: on return, word is reset, but not o_free'd!
- */
-static int done_word(o_string *word, struct parse_context *ctx)
-{
- struct command *command = ctx->command;
+ close(redir->rd_fd); /* often saves dup2+close in xmove_fd */
+ xpiped_pair(pair);
+ xmove_fd(pair.rd, redir->rd_fd);
- debug_printf_parse("done_word entered: '%s' %p\n", word->data, command);
- if (word->length == 0 && word->o_quoted == 0) {
- debug_printf_parse("done_word return 0: true null, ignored\n");
- return 0;
+ /* Try writing without forking. Newer kernels have
+ * dynamically growing pipes. Must use non-blocking write! */
+ ndelay_on(pair.wr);
+ while (1) {
+ written = write(pair.wr, heredoc, len);
+ if (written <= 0)
+ break;
+ len -= written;
+ if (len == 0) {
+ close(pair.wr);
+ free(expanded);
+ return;
+ }
+ heredoc += written;
+ }
+ ndelay_off(pair.wr);
+
+ /* Okay, pipe buffer was not big enough */
+ /* Note: we must not create a stray child (bastard? :)
+ * for the unsuspecting parent process. Child creates a grandchild
+ * and exits before parent execs the process which consumes heredoc
+ * (that exec happens after we return from this function) */
+#if !BB_MMU
+ to_free = NULL;
+#endif
+ pid = xvfork();
+ if (pid == 0) {
+ /* child */
+ disable_restore_tty_pgrp_on_exit();
+ pid = BB_MMU ? xfork() : xvfork();
+ if (pid != 0)
+ _exit(0);
+ /* grandchild */
+ close(redir->rd_fd); /* read side of the pipe */
+#if BB_MMU
+ full_write(pair.wr, heredoc, len); /* may loop or block */
+ _exit(0);
+#else
+ /* Delegate blocking writes to another process */
+ xmove_fd(pair.wr, STDOUT_FILENO);
+ re_execute_shell(&to_free, heredoc, NULL, NULL, NULL);
+#endif
}
+ /* parent */
+#if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] fork in setup_heredoc: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+#endif
+ enable_restore_tty_pgrp_on_exit();
+#if !BB_MMU
+ free(to_free);
+#endif
+ close(pair.wr);
+ free(expanded);
+ wait(NULL); /* wait till child has died */
+}
- if (ctx->pending_redirect) {
- /* We do not glob in e.g. >*.tmp case. bash seems to glob here
- * only if run as "bash", not "sh" */
- /* http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
- * "2.7 Redirection
- * ...the word that follows the redirection operator
- * shall be subjected to tilde expansion, parameter expansion,
- * command substitution, arithmetic expansion, and quote
- * removal. Pathname expansion shall not be performed
- * on the word by a non-interactive shell; an interactive
- * shell may perform it, but shall do so only when
- * the expansion would result in one word."
- */
- ctx->pending_redirect->rd_filename = xstrdup(word->data);
- /* Cater for >\file case:
- * >\a creates file a; >\\a, >"\a", >"\\a" create file \a
- * Same with heredocs:
- * for <<\H delim is H; <<\\H, <<"\H", <<"\\H" - \H
- */
- if (ctx->pending_redirect->rd_type == REDIRECT_HEREDOC) {
- unbackslash(ctx->pending_redirect->rd_filename);
- /* Is it <<"HEREDOC"? */
- if (word->o_quoted) {
- ctx->pending_redirect->rd_dup |= HEREDOC_QUOTED;
+/* squirrel != NULL means we squirrel away copies of stdin, stdout,
+ * and stderr if they are redirected. */
+static int setup_redirects(struct command *prog, int squirrel[])
+{
+ int openfd, mode;
+ struct redir_struct *redir;
+
+ for (redir = prog->redirects; redir; redir = redir->next) {
+ if (redir->rd_type == REDIRECT_HEREDOC2) {
+ /* rd_fd<<HERE case */
+ if (squirrel && redir->rd_fd < 3
+ && squirrel[redir->rd_fd] < 0
+ ) {
+ squirrel[redir->rd_fd] = dup(redir->rd_fd);
}
- }
- debug_printf_parse("word stored in rd_filename: '%s'\n", word->data);
- ctx->pending_redirect = NULL;
- } else {
- /* If this word wasn't an assignment, next ones definitely
- * can't be assignments. Even if they look like ones. */
- if (word->o_assignment != DEFINITELY_ASSIGNMENT
- && word->o_assignment != WORD_IS_KEYWORD
- ) {
- word->o_assignment = NOT_ASSIGNMENT;
- } else {
- if (word->o_assignment == DEFINITELY_ASSIGNMENT)
- command->assignment_cnt++;
- word->o_assignment = MAYBE_ASSIGNMENT;
+ /* for REDIRECT_HEREDOC2, rd_filename holds _contents_
+ * of the heredoc */
+ debug_printf_parse("set heredoc '%s'\n",
+ redir->rd_filename);
+ setup_heredoc(redir);
+ continue;
}
-#if HAS_KEYWORDS
-# if ENABLE_HUSH_CASE
- if (ctx->ctx_dsemicolon
- && strcmp(word->data, "esac") != 0 /* not "... pattern) cmd;; esac" */
- ) {
- /* already done when ctx_dsemicolon was set to 1: */
- /* ctx->ctx_res_w = RES_MATCH; */
- ctx->ctx_dsemicolon = 0;
- } else
-# endif
- if (!command->argv /* if it's the first word... */
-# if ENABLE_HUSH_LOOPS
- && ctx->ctx_res_w != RES_FOR /* ...not after FOR or IN */
- && ctx->ctx_res_w != RES_IN
-# endif
-# if ENABLE_HUSH_CASE
- && ctx->ctx_res_w != RES_CASE
-# endif
- ) {
- debug_printf_parse("checking '%s' for reserved-ness\n", word->data);
- if (reserved_word(word, ctx)) {
- o_reset_to_empty_unquoted(word);
- debug_printf_parse("done_word return %d\n",
- (ctx->ctx_res_w == RES_SNTX));
- return (ctx->ctx_res_w == RES_SNTX);
+ if (redir->rd_dup == REDIRFD_TO_FILE) {
+ /* rd_fd<*>file case (<*> is <,>,>>,<>) */
+ char *p;
+ if (redir->rd_filename == NULL) {
+ /* Something went wrong in the parse.
+ * Pretend it didn't happen */
+ bb_error_msg("bug in redirect parse");
+ continue;
}
-# ifdef CMD_SINGLEWORD_NOGLOB_COND
- if (strcmp(word->data, "export") == 0
-# if ENABLE_HUSH_LOCAL
- || strcmp(word->data, "local") == 0
-# endif
- ) {
- command->cmd_type = CMD_SINGLEWORD_NOGLOB_COND;
- } else
-# endif
-# if ENABLE_HUSH_BASH_COMPAT
- if (strcmp(word->data, "[[") == 0) {
- command->cmd_type = CMD_SINGLEWORD_NOGLOB;
+ mode = redir_table[redir->rd_type].mode;
+ p = expand_string_to_string(redir->rd_filename);
+ openfd = open_or_warn(p, mode);
+ free(p);
+ if (openfd < 0) {
+ /* this could get lost if stderr has been redirected, but
+ * bash and ash both lose it as well (though zsh doesn't!) */
+//what the above comment tries to say?
+ return 1;
}
- /* fall through */
-# endif
- }
-#endif
- if (command->group) {
- /* "{ echo foo; } echo bar" - bad */
- syntax_error_at(word->data);
- debug_printf_parse("done_word return 1: syntax error, "
- "groups and arglists don't mix\n");
- return 1;
+ } else {
+ /* rd_fd<*>rd_dup or rd_fd<*>- cases */
+ openfd = redir->rd_dup;
}
- if (word->o_quoted /* word had "xx" or 'xx' at least as part of it. */
- /* optimization: and if it's ("" or '') or ($v... or `cmd`...): */
- && (word->data[0] == '\0' || word->data[0] == SPECIAL_VAR_SYMBOL)
- /* (otherwise it's known to be not empty and is already safe) */
- ) {
- /* exclude "$@" - it can expand to no word despite "" */
- char *p = word->data;
- while (p[0] == SPECIAL_VAR_SYMBOL
- && (p[1] & 0x7f) == '@'
- && p[2] == SPECIAL_VAR_SYMBOL
+
+ if (openfd != redir->rd_fd) {
+ if (squirrel && redir->rd_fd < 3
+ && squirrel[redir->rd_fd] < 0
) {
- p += 3;
+ squirrel[redir->rd_fd] = dup(redir->rd_fd);
}
- if (p == word->data || p[0] != '\0') {
- /* saw no "$@", or not only "$@" but some
- * real text is there too */
- /* insert "empty variable" reference, this makes
- * e.g. "", $empty"" etc to not disappear */
- o_addchr(word, SPECIAL_VAR_SYMBOL);
- o_addchr(word, SPECIAL_VAR_SYMBOL);
+ if (openfd == REDIRFD_CLOSE) {
+ /* "n>-" means "close me" */
+ close(redir->rd_fd);
+ } else {
+ xdup2(openfd, redir->rd_fd);
+ if (redir->rd_dup == REDIRFD_TO_FILE)
+ close(openfd);
}
}
- command->argv = add_string_to_strings(command->argv, xstrdup(word->data));
- debug_print_strings("word appended to argv", command->argv);
}
+ return 0;
+}
-#if ENABLE_HUSH_LOOPS
- if (ctx->ctx_res_w == RES_FOR) {
- if (word->o_quoted
- || !is_well_formed_var_name(command->argv[0], '\0')
- ) {
- /* bash says just "not a valid identifier" */
- syntax_error("not a valid identifier in for");
- return 1;
+static void restore_redirects(int squirrel[])
+{
+ int i, fd;
+ for (i = 0; i < 3; i++) {
+ fd = squirrel[i];
+ if (fd != -1) {
+ /* We simply die on error */
+ xmove_fd(fd, i);
}
- /* Force FOR to have just one word (variable name) */
- /* NB: basically, this makes hush see "for v in ..."
- * syntax as if it is "for v; in ...". FOR and IN become
- * two pipe structs in parse tree. */
- done_pipe(ctx, PIPE_SEQ);
- }
-#endif
-#if ENABLE_HUSH_CASE
- /* Force CASE to have just one word */
- if (ctx->ctx_res_w == RES_CASE) {
- done_pipe(ctx, PIPE_SEQ);
}
-#endif
-
- o_reset_to_empty_unquoted(word);
-
- debug_printf_parse("done_word return 0\n");
- return 0;
}
-
-/* Peek ahead in the input to find out if we have a "&n" construct,
- * as in "2>&1", that represents duplicating a file descriptor.
- * Return:
- * REDIRFD_CLOSE if >&- "close fd" construct is seen,
- * REDIRFD_SYNTAX_ERR if syntax error,
- * REDIRFD_TO_FILE if no & was seen,
- * or the number found.
- */
-#if BB_MMU
-#define parse_redir_right_fd(as_string, input) \
- parse_redir_right_fd(input)
-#endif
-static int parse_redir_right_fd(o_string *as_string, struct in_str *input)
+static char *find_in_path(const char *arg)
{
- int ch, d, ok;
+ char *ret = NULL;
+ const char *PATH = get_local_var_value("PATH");
- ch = i_peek(input);
- if (ch != '&')
- return REDIRFD_TO_FILE;
+ if (!PATH)
+ return NULL;
- ch = i_getch(input); /* get the & */
- nommu_addchr(as_string, ch);
- ch = i_peek(input);
- if (ch == '-') {
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- return REDIRFD_CLOSE;
- }
- d = 0;
- ok = 0;
- while (ch != EOF && isdigit(ch)) {
- d = d*10 + (ch-'0');
- ok = 1;
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- ch = i_peek(input);
+ while (1) {
+ const char *end = strchrnul(PATH, ':');
+ int sz = end - PATH; /* must be int! */
+
+ free(ret);
+ if (sz != 0) {
+ ret = xasprintf("%.*s/%s", sz, PATH, arg);
+ } else {
+ /* We have xxx::yyyy in $PATH,
+ * it means "use current dir" */
+ ret = xstrdup(arg);
+ }
+ if (access(ret, F_OK) == 0)
+ break;
+
+ if (*end == '\0') {
+ free(ret);
+ return NULL;
+ }
+ PATH = end + 1;
}
- if (ok) return d;
-//TODO: this is the place to catch ">&file" bashism (redirect both fd 1 and 2)
+ return ret;
+}
- bb_error_msg("ambiguous redirect");
- return REDIRFD_SYNTAX_ERR;
+static const struct built_in_command *find_builtin_helper(const char *name,
+ const struct built_in_command *x,
+ const struct built_in_command *end)
+{
+ while (x != end) {
+ if (strcmp(name, x->b_cmd) != 0) {
+ x++;
+ continue;
+ }
+ debug_printf_exec("found builtin '%s'\n", name);
+ return x;
+ }
+ return NULL;
}
-
-/* Return code is 0 normal, 1 if a syntax error is detected
- */
-static int parse_redirect(struct parse_context *ctx,
- int fd,
- redir_type style,
- struct in_str *input)
+static const struct built_in_command *find_builtin1(const char *name)
{
- struct command *command = ctx->command;
- struct redir_struct *redir;
- struct redir_struct **redirp;
- int dup_num;
+ return find_builtin_helper(name, bltins1, &bltins1[ARRAY_SIZE(bltins1)]);
+}
+static const struct built_in_command *find_builtin(const char *name)
+{
+ const struct built_in_command *x = find_builtin1(name);
+ if (x)
+ return x;
+ return find_builtin_helper(name, bltins2, &bltins2[ARRAY_SIZE(bltins2)]);
+}
- dup_num = REDIRFD_TO_FILE;
- if (style != REDIRECT_HEREDOC) {
- /* Check for a '>&1' type redirect */
- dup_num = parse_redir_right_fd(&ctx->as_string, input);
- if (dup_num == REDIRFD_SYNTAX_ERR)
- return 1;
- } else {
- int ch = i_peek(input);
- dup_num = (ch == '-'); /* HEREDOC_SKIPTABS bit is 1 */
- if (dup_num) { /* <<-... */
- ch = i_getch(input);
- nommu_addchr(&ctx->as_string, ch);
- ch = i_peek(input);
+#if ENABLE_HUSH_FUNCTIONS
+static struct function **find_function_slot(const char *name)
+{
+ struct function **funcpp = &G.top_func;
+ while (*funcpp) {
+ if (strcmp(name, (*funcpp)->name) == 0) {
+ break;
}
+ funcpp = &(*funcpp)->next;
}
+ return funcpp;
+}
- if (style == REDIRECT_OVERWRITE && dup_num == REDIRFD_TO_FILE) {
- int ch = i_peek(input);
- if (ch == '|') {
- /* >|FILE redirect ("clobbering" >).
- * Since we do not support "set -o noclobber" yet,
- * >| and > are the same for now. Just eat |.
- */
- ch = i_getch(input);
- nommu_addchr(&ctx->as_string, ch);
+static const struct function *find_function(const char *name)
+{
+ const struct function *funcp = *find_function_slot(name);
+ if (funcp)
+ debug_printf_exec("found function '%s'\n", name);
+ return funcp;
+}
+
+/* Note: takes ownership on name ptr */
+static struct function *new_function(char *name)
+{
+ struct function **funcpp = find_function_slot(name);
+ struct function *funcp = *funcpp;
+
+ if (funcp != NULL) {
+ struct command *cmd = funcp->parent_cmd;
+ debug_printf_exec("func %p parent_cmd %p\n", funcp, cmd);
+ if (!cmd) {
+ debug_printf_exec("freeing & replacing function '%s'\n", funcp->name);
+ free(funcp->name);
+ /* Note: if !funcp->body, do not free body_as_string!
+ * This is a special case of "-F name body" function:
+ * body_as_string was not malloced! */
+ if (funcp->body) {
+ free_pipe_list(funcp->body);
+# if !BB_MMU
+ free(funcp->body_as_string);
+# endif
+ }
+ } else {
+ debug_printf_exec("reinserting in tree & replacing function '%s'\n", funcp->name);
+ cmd->argv[0] = funcp->name;
+ cmd->group = funcp->body;
+# if !BB_MMU
+ cmd->group_as_string = funcp->body_as_string;
+# endif
}
+ } else {
+ debug_printf_exec("remembering new function '%s'\n", name);
+ funcp = *funcpp = xzalloc(sizeof(*funcp));
+ /*funcp->next = NULL;*/
}
- /* Create a new redir_struct and append it to the linked list */
- redirp = &command->redirects;
- while ((redir = *redirp) != NULL) {
- redirp = &(redir->next);
- }
- *redirp = redir = xzalloc(sizeof(*redir));
- /* redir->next = NULL; */
- /* redir->rd_filename = NULL; */
- redir->rd_type = style;
- redir->rd_fd = (fd == -1) ? redir_table[style].default_fd : fd;
+ funcp->name = name;
+ return funcp;
+}
- debug_printf_parse("redirect type %d %s\n", redir->rd_fd,
- redir_table[style].descrip);
+static void unset_func(const char *name)
+{
+ struct function **funcpp = find_function_slot(name);
+ struct function *funcp = *funcpp;
- redir->rd_dup = dup_num;
- if (style != REDIRECT_HEREDOC && dup_num != REDIRFD_TO_FILE) {
- /* Erik had a check here that the file descriptor in question
- * is legit; I postpone that to "run time"
- * A "-" representation of "close me" shows up as a -3 here */
- debug_printf_parse("duplicating redirect '%d>&%d'\n",
- redir->rd_fd, redir->rd_dup);
- } else {
- /* Set ctx->pending_redirect, so we know what to do at the
- * end of the next parsed word. */
- ctx->pending_redirect = redir;
+ if (funcp != NULL) {
+ debug_printf_exec("freeing function '%s'\n", funcp->name);
+ *funcpp = funcp->next;
+ /* funcp is unlinked now, deleting it.
+ * Note: if !funcp->body, the function was created by
+ * "-F name body", do not free ->body_as_string
+ * and ->name as they were not malloced. */
+ if (funcp->body) {
+ free_pipe_list(funcp->body);
+ free(funcp->name);
+# if !BB_MMU
+ free(funcp->body_as_string);
+# endif
+ }
+ free(funcp);
}
- return 0;
}
-/* If a redirect is immediately preceded by a number, that number is
- * supposed to tell which file descriptor to redirect. This routine
- * looks for such preceding numbers. In an ideal world this routine
- * needs to handle all the following classes of redirects...
- * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
- * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
- * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
- * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
- *
- * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
- * "2.7 Redirection
- * ... If n is quoted, the number shall not be recognized as part of
- * the redirection expression. For example:
- * echo \2>a
- * writes the character 2 into file a"
- * We are getting it right by setting ->o_quoted on any \<char>
- *
- * A -1 return means no valid number was found,
- * the caller should use the appropriate default for this redirection.
- */
-static int redirect_opt_num(o_string *o)
+# if BB_MMU
+#define exec_function(to_free, funcp, argv) \
+ exec_function(funcp, argv)
+# endif
+static void exec_function(char ***to_free,
+ const struct function *funcp,
+ char **argv) NORETURN;
+static void exec_function(char ***to_free,
+ const struct function *funcp,
+ char **argv)
{
- int num;
+# if BB_MMU
+ int n = 1;
- if (o->data == NULL)
- return -1;
- num = bb_strtou(o->data, NULL, 10);
- if (errno || num < 0)
- return -1;
- o_reset_to_empty_unquoted(o);
- return num;
+ argv[0] = G.global_argv[0];
+ G.global_argv = argv;
+ while (*++argv)
+ n++;
+ G.global_argc = n;
+ /* On MMU, funcp->body is always non-NULL */
+ n = run_list(funcp->body);
+ fflush_all();
+ _exit(n);
+# else
+ re_execute_shell(to_free,
+ funcp->body_as_string,
+ G.global_argv[0],
+ argv + 1,
+ NULL);
+# endif
}
-#if BB_MMU
-#define fetch_till_str(as_string, input, word, skip_tabs) \
- fetch_till_str(input, word, skip_tabs)
-#endif
-static char *fetch_till_str(o_string *as_string,
- struct in_str *input,
- const char *word,
- int skip_tabs)
+static int run_function(const struct function *funcp, char **argv)
{
- o_string heredoc = NULL_O_STRING;
- int past_EOL = 0;
- int ch;
+ int rc;
+ save_arg_t sv;
+ smallint sv_flg;
- goto jump_in;
- while (1) {
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- if (ch == '\n') {
- if (strcmp(heredoc.data + past_EOL, word) == 0) {
- heredoc.data[past_EOL] = '\0';
- debug_printf_parse("parsed heredoc '%s'\n", heredoc.data);
- return heredoc.data;
- }
- do {
- o_addchr(&heredoc, ch);
- past_EOL = heredoc.length;
- jump_in:
- do {
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- } while (skip_tabs && ch == '\t');
- } while (ch == '\n');
- }
- if (ch == EOF) {
- o_free_unsafe(&heredoc);
- return NULL;
+ save_and_replace_G_args(&sv, argv);
+
+ /* "we are in function, ok to use return" */
+ sv_flg = G.flag_return_in_progress;
+ G.flag_return_in_progress = -1;
+# if ENABLE_HUSH_LOCAL
+ G.func_nest_level++;
+# endif
+
+ /* On MMU, funcp->body is always non-NULL */
+# if !BB_MMU
+ if (!funcp->body) {
+ /* Function defined by -F */
+ parse_and_run_string(funcp->body_as_string);
+ rc = G.last_exitcode;
+ } else
+# endif
+ {
+ rc = run_list(funcp->body);
+ }
+
+# if ENABLE_HUSH_LOCAL
+ {
+ struct variable *var;
+ struct variable **var_pp;
+
+ var_pp = &G.top_var;
+ while ((var = *var_pp) != NULL) {
+ if (var->func_nest_level < G.func_nest_level) {
+ var_pp = &var->next;
+ continue;
+ }
+ /* Unexport */
+ if (var->flg_export)
+ bb_unsetenv(var->varstr);
+ /* Remove from global list */
+ *var_pp = var->next;
+ /* Free */
+ if (!var->max_len)
+ free(var->varstr);
+ free(var);
}
- o_addchr(&heredoc, ch);
- nommu_addchr(as_string, ch);
+ G.func_nest_level--;
}
+# endif
+ G.flag_return_in_progress = sv_flg;
+
+ restore_G_args(&sv, argv);
+
+ return rc;
}
+#endif /* ENABLE_HUSH_FUNCTIONS */
-/* Look at entire parse tree for not-yet-loaded REDIRECT_HEREDOCs
- * and load them all. There should be exactly heredoc_cnt of them.
- */
-static int fetch_heredocs(int heredoc_cnt, struct parse_context *ctx, struct in_str *input)
+
+#if BB_MMU
+#define exec_builtin(to_free, x, argv) \
+ exec_builtin(x, argv)
+#else
+#define exec_builtin(to_free, x, argv) \
+ exec_builtin(to_free, argv)
+#endif
+static void exec_builtin(char ***to_free,
+ const struct built_in_command *x,
+ char **argv) NORETURN;
+static void exec_builtin(char ***to_free,
+ const struct built_in_command *x,
+ char **argv)
{
- struct pipe *pi = ctx->list_head;
+#if BB_MMU
+ int rcode = x->b_function(argv);
+ fflush_all();
+ _exit(rcode);
+#else
+ /* On NOMMU, we must never block!
+ * Example: { sleep 99 | read line; } & echo Ok
+ */
+ re_execute_shell(to_free,
+ argv[0],
+ G.global_argv[0],
+ G.global_argv + 1,
+ argv);
+#endif
+}
- while (pi && heredoc_cnt) {
- int i;
- struct command *cmd = pi->cmds;
- debug_printf_parse("fetch_heredocs: num_cmds:%d cmd argv0:'%s'\n",
- pi->num_cmds,
- cmd->argv ? cmd->argv[0] : "NONE");
- for (i = 0; i < pi->num_cmds; i++) {
- struct redir_struct *redir = cmd->redirects;
+static void execvp_or_die(char **argv) NORETURN;
+static void execvp_or_die(char **argv)
+{
+ debug_printf_exec("execing '%s'\n", argv[0]);
+ sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
+ execvp(argv[0], argv);
+ bb_perror_msg("can't execute '%s'", argv[0]);
+ _exit(127); /* bash compat */
+}
- debug_printf_parse("fetch_heredocs: %d cmd argv0:'%s'\n",
- i, cmd->argv ? cmd->argv[0] : "NONE");
- while (redir) {
- if (redir->rd_type == REDIRECT_HEREDOC) {
- char *p;
+#if ENABLE_HUSH_MODE_X
+static void dump_cmd_in_x_mode(char **argv)
+{
+ if (G_x_mode && argv) {
+ /* We want to output the line in one write op */
+ char *buf, *p;
+ int len;
+ int n;
- redir->rd_type = REDIRECT_HEREDOC2;
- /* redir->rd_dup is (ab)used to indicate <<- */
- p = fetch_till_str(&ctx->as_string, input,
- redir->rd_filename, redir->rd_dup & HEREDOC_SKIPTABS);
- if (!p) {
- syntax_error("unexpected EOF in here document");
- return 1;
- }
- free(redir->rd_filename);
- redir->rd_filename = p;
- heredoc_cnt--;
- }
- redir = redir->next;
- }
- cmd++;
- }
- pi = pi->next;
+ len = 3;
+ n = 0;
+ while (argv[n])
+ len += strlen(argv[n++]) + 1;
+ buf = xmalloc(len);
+ buf[0] = '+';
+ p = buf + 1;
+ n = 0;
+ while (argv[n])
+ p += sprintf(p, " %s", argv[n++]);
+ *p++ = '\n';
+ *p = '\0';
+ fputs(buf, stderr);
+ free(buf);
}
-#if 0
- /* Should be 0. If it isn't, it's a parse error */
- if (heredoc_cnt)
- bb_error_msg_and_die("heredoc BUG 2");
-#endif
- return 0;
}
+#else
+# define dump_cmd_in_x_mode(argv) ((void)0)
+#endif
+#if BB_MMU
+#define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \
+ pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
+#define pseudo_exec(nommu_save, command, argv_expanded) \
+ pseudo_exec(command, argv_expanded)
+#endif
-#if ENABLE_HUSH_TICK
-static FILE *generate_stream_from_string(const char *s, pid_t *pid_p)
+/* Called after [v]fork() in run_pipe, or from builtin_exec.
+ * Never returns.
+ * Don't exit() here. If you don't exec, use _exit instead.
+ * The at_exit handlers apparently confuse the calling process,
+ * in particular stdin handling. Not sure why? -- because of vfork! (vda) */
+static void pseudo_exec_argv(nommu_save_t *nommu_save,
+ char **argv, int assignment_cnt,
+ char **argv_expanded) NORETURN;
+static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
+ char **argv, int assignment_cnt,
+ char **argv_expanded)
{
- pid_t pid;
- int channel[2];
-# if !BB_MMU
- char **to_free = NULL;
-# endif
+ char **new_env;
- xpipe(channel);
- pid = BB_MMU ? xfork() : xvfork();
- if (pid == 0) { /* child */
- disable_restore_tty_pgrp_on_exit();
- /* Process substitution is not considered to be usual
- * 'command execution'.
- * SUSv3 says ctrl-Z should be ignored, ctrl-C should not.
- */
- bb_signals(0
- + (1 << SIGTSTP)
- + (1 << SIGTTIN)
- + (1 << SIGTTOU)
- , SIG_IGN);
- CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
- close(channel[0]); /* NB: close _first_, then move fd! */
- xmove_fd(channel[1], 1);
- /* Prevent it from trying to handle ctrl-z etc */
- IF_HUSH_JOB(G.run_list_level = 1;)
- /* Awful hack for `trap` or $(trap).
- *
- * http://www.opengroup.org/onlinepubs/009695399/utilities/trap.html
- * contains an example where "trap" is executed in a subshell:
- *
- * save_traps=$(trap)
- * ...
- * eval "$save_traps"
- *
- * Standard does not say that "trap" in subshell shall print
- * parent shell's traps. It only says that its output
- * must have suitable form, but then, in the above example
- * (which is not supposed to be normative), it implies that.
- *
- * bash (and probably other shell) does implement it
- * (traps are reset to defaults, but "trap" still shows them),
- * but as a result, "trap" logic is hopelessly messed up:
- *
- * # trap
- * trap -- 'echo Ho' SIGWINCH <--- we have a handler
- * # (trap) <--- trap is in subshell - no output (correct, traps are reset)
- * # true | trap <--- trap is in subshell - no output (ditto)
- * # echo `true | trap` <--- in subshell - output (but traps are reset!)
- * trap -- 'echo Ho' SIGWINCH
- * # echo `(trap)` <--- in subshell in subshell - output
- * trap -- 'echo Ho' SIGWINCH
- * # echo `true | (trap)` <--- in subshell in subshell in subshell - output!
- * trap -- 'echo Ho' SIGWINCH
- *
- * The rules when to forget and when to not forget traps
- * get really complex and nonsensical.
- *
- * Our solution: ONLY bare $(trap) or `trap` is special.
+ new_env = expand_assignments(argv, assignment_cnt);
+ dump_cmd_in_x_mode(new_env);
+
+ if (!argv[assignment_cnt]) {
+ /* Case when we are here: ... | var=val | ...
+ * (note that we do not exit early, i.e., do not optimize out
+ * expand_assignments(): think about ... | var=`sleep 1` | ...
*/
- s = skip_whitespace(s);
- if (strncmp(s, "trap", 4) == 0 && (*skip_whitespace(s + 4) == '\0'))
- {
- static const char *const argv[] = { NULL, NULL };
- builtin_trap((char**)argv);
- exit(0); /* not _exit() - we need to fflush */
- }
-# if BB_MMU
- reset_traps_to_defaults();
- parse_and_run_string(s);
- _exit(G.last_exitcode);
-# else
- /* We re-execute after vfork on NOMMU. This makes this script safe:
- * yes "0123456789012345678901234567890" | dd bs=32 count=64k >BIG
- * huge=`cat BIG` # was blocking here forever
- * echo OK
- */
- re_execute_shell(&to_free,
- s,
- G.global_argv[0],
- G.global_argv + 1,
- NULL);
-# endif
+ free_strings(new_env);
+ _exit(EXIT_SUCCESS);
}
- /* parent */
- *pid_p = pid;
-# if ENABLE_HUSH_FAST
- G.count_SIGCHLD++;
-//bb_error_msg("[%d] fork in generate_stream_from_string: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
-# endif
- enable_restore_tty_pgrp_on_exit();
-# if !BB_MMU
- free(to_free);
-# endif
- close(channel[1]);
- close_on_exec_on(channel[0]);
- return xfdopen_for_read(channel[0]);
-}
-
-/* Return code is exit status of the process that is run. */
-static int process_command_subs(o_string *dest, const char *s)
-{
- FILE *fp;
- struct in_str pipe_str;
- pid_t pid;
- int status, ch, eol_cnt;
-
- fp = generate_stream_from_string(s, &pid);
+#if BB_MMU
+ set_vars_and_save_old(new_env);
+ free(new_env); /* optional */
+ /* we can also destroy set_vars_and_save_old's return value,
+ * to save memory */
+#else
+ nommu_save->new_env = new_env;
+ nommu_save->old_vars = set_vars_and_save_old(new_env);
+#endif
- /* Now send results of command back into original context */
- setup_file_in_str(&pipe_str, fp);
- eol_cnt = 0;
- while ((ch = i_getch(&pipe_str)) != EOF) {
- if (ch == '\n') {
- eol_cnt++;
- continue;
- }
- while (eol_cnt) {
- o_addchr(dest, '\n');
- eol_cnt--;
- }
- o_addQchr(dest, ch);
+ if (argv_expanded) {
+ argv = argv_expanded;
+ } else {
+ argv = expand_strvec_to_strvec(argv + assignment_cnt);
+#if !BB_MMU
+ nommu_save->argv = argv;
+#endif
}
+ dump_cmd_in_x_mode(argv);
- debug_printf("done reading from `cmd` pipe, closing it\n");
- fclose(fp);
- /* We need to extract exitcode. Test case
- * "true; echo `sleep 1; false` $?"
- * should print 1 */
- safe_waitpid(pid, &status, 0);
- debug_printf("child exited. returning its exitcode:%d\n", WEXITSTATUS(status));
- return WEXITSTATUS(status);
-}
-#endif /* ENABLE_HUSH_TICK */
-
-#if !ENABLE_HUSH_FUNCTIONS
-#define parse_group(dest, ctx, input, ch) \
- parse_group(ctx, input, ch)
+#if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
+ if (strchr(argv[0], '/') != NULL)
+ goto skip;
#endif
-static int parse_group(o_string *dest, struct parse_context *ctx,
- struct in_str *input, int ch)
-{
- /* dest contains characters seen prior to ( or {.
- * Typically it's empty, but for function defs,
- * it contains function name (without '()'). */
- struct pipe *pipe_list;
- int endch;
- struct command *command = ctx->command;
- debug_printf_parse("parse_group entered\n");
-#if ENABLE_HUSH_FUNCTIONS
- if (ch == '(' && !dest->o_quoted) {
- if (dest->length)
- if (done_word(dest, ctx))
- return 1;
- if (!command->argv)
- goto skip; /* (... */
- if (command->argv[1]) { /* word word ... (... */
- syntax_error_unexpected_ch('(');
- return 1;
- }
- /* it is "word(..." or "word (..." */
- do
- ch = i_getch(input);
- while (ch == ' ' || ch == '\t');
- if (ch != ')') {
- syntax_error_unexpected_ch(ch);
- return 1;
+ /* Check if the command matches any of the builtins.
+ * Depending on context, this might be redundant. But it's
+ * easier to waste a few CPU cycles than it is to figure out
+ * if this is one of those cases.
+ */
+ {
+ /* On NOMMU, it is more expensive to re-execute shell
+ * just in order to run echo or test builtin.
+ * It's better to skip it here and run corresponding
+ * non-builtin later. */
+ const struct built_in_command *x;
+ x = BB_MMU ? find_builtin(argv[0]) : find_builtin1(argv[0]);
+ if (x) {
+ exec_builtin(&nommu_save->argv_from_re_execing, x, argv);
}
- nommu_addchr(&ctx->as_string, ch);
- do
- ch = i_getch(input);
- while (ch == ' ' || ch == '\t' || ch == '\n');
- if (ch != '{') {
- syntax_error_unexpected_ch(ch);
- return 1;
+ }
+#if ENABLE_HUSH_FUNCTIONS
+ /* Check if the command matches any functions */
+ {
+ const struct function *funcp = find_function(argv[0]);
+ if (funcp) {
+ exec_function(&nommu_save->argv_from_re_execing, funcp, argv);
}
- nommu_addchr(&ctx->as_string, ch);
- command->cmd_type = CMD_FUNCDEF;
- goto skip;
}
#endif
-#if 0 /* Prevented by caller */
- if (command->argv /* word [word]{... */
- || dest->length /* word{... */
- || dest->o_quoted /* ""{... */
- ) {
- syntax_error(NULL);
- debug_printf_parse("parse_group return 1: "
- "syntax error, groups and arglists don't mix\n");
- return 1;
+#if ENABLE_FEATURE_SH_STANDALONE
+ /* Check if the command matches any busybox applets */
+ {
+ int a = find_applet_by_name(argv[0]);
+ if (a >= 0) {
+# if BB_MMU /* see above why on NOMMU it is not allowed */
+ if (APPLET_IS_NOEXEC(a)) {
+ debug_printf_exec("running applet '%s'\n", argv[0]);
+ run_applet_no_and_exit(a, argv);
+ }
+# endif
+ /* Re-exec ourselves */
+ debug_printf_exec("re-execing applet '%s'\n", argv[0]);
+ sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
+ execv(bb_busybox_exec_path, argv);
+ /* If they called chroot or otherwise made the binary no longer
+ * executable, fall through */
+ }
}
#endif
-#if ENABLE_HUSH_FUNCTIONS
+#if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
skip:
#endif
- endch = '}';
- if (ch == '(') {
- endch = ')';
- command->cmd_type = CMD_SUBSHELL;
- } else {
- /* bash does not allow "{echo...", requires whitespace */
- ch = i_getch(input);
- if (ch != ' ' && ch != '\t' && ch != '\n') {
- syntax_error_unexpected_ch(ch);
- return 1;
- }
- nommu_addchr(&ctx->as_string, ch);
+ execvp_or_die(argv);
+}
+
+/* Called after [v]fork() in run_pipe
+ */
+static void pseudo_exec(nommu_save_t *nommu_save,
+ struct command *command,
+ char **argv_expanded) NORETURN;
+static void pseudo_exec(nommu_save_t *nommu_save,
+ struct command *command,
+ char **argv_expanded)
+{
+ if (command->argv) {
+ pseudo_exec_argv(nommu_save, command->argv,
+ command->assignment_cnt, argv_expanded);
}
- {
+ if (command->group) {
+ /* Cases when we are here:
+ * ( list )
+ * { list } &
+ * ... | ( list ) | ...
+ * ... | { list } | ...
+ */
#if BB_MMU
-# define as_string NULL
+ int rcode;
+ debug_printf_exec("pseudo_exec: run_list\n");
+ reset_traps_to_defaults();
+ rcode = run_list(command->group);
+ /* OK to leak memory by not calling free_pipe_list,
+ * since this process is about to exit */
+ _exit(rcode);
#else
- char *as_string = NULL;
-#endif
- pipe_list = parse_stream(&as_string, input, endch);
-#if !BB_MMU
- if (as_string)
- o_addstr(&ctx->as_string, as_string);
-#endif
- /* empty ()/{} or parse error? */
- if (!pipe_list || pipe_list == ERR_PTR) {
- /* parse_stream already emitted error msg */
- if (!BB_MMU)
- free(as_string);
- debug_printf_parse("parse_group return 1: "
- "parse_stream returned %p\n", pipe_list);
- return 1;
- }
- command->group = pipe_list;
-#if !BB_MMU
- as_string[strlen(as_string) - 1] = '\0'; /* plink ')' or '}' */
- command->group_as_string = as_string;
- debug_printf_parse("end of group, remembering as:'%s'\n",
- command->group_as_string);
+ re_execute_shell(&nommu_save->argv_from_re_execing,
+ command->group_as_string,
+ G.global_argv[0],
+ G.global_argv + 1,
+ NULL);
#endif
-#undef as_string
}
- debug_printf_parse("parse_group return 0\n");
- return 0;
- /* command remains "open", available for possible redirects */
+
+ /* Case when we are here: ... | >file */
+ debug_printf_exec("pseudo_exec'ed null command\n");
+ _exit(EXIT_SUCCESS);
+}
+
+#if ENABLE_HUSH_JOB
+static const char *get_cmdtext(struct pipe *pi)
+{
+ char **argv;
+ char *p;
+ int len;
+
+ /* This is subtle. ->cmdtext is created only on first backgrounding.
+ * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...)
+ * On subsequent bg argv is trashed, but we won't use it */
+ if (pi->cmdtext)
+ return pi->cmdtext;
+ argv = pi->cmds[0].argv;
+ if (!argv || !argv[0]) {
+ pi->cmdtext = xzalloc(1);
+ return pi->cmdtext;
+ }
+
+ len = 0;
+ do {
+ len += strlen(*argv) + 1;
+ } while (*++argv);
+ p = xmalloc(len);
+ pi->cmdtext = p;
+ argv = pi->cmds[0].argv;
+ do {
+ len = strlen(*argv);
+ memcpy(p, *argv, len);
+ p += len;
+ *p++ = ' ';
+ } while (*++argv);
+ p[-1] = '\0';
+ return pi->cmdtext;
+}
+
+static void insert_bg_job(struct pipe *pi)
+{
+ struct pipe *job, **jobp;
+ int i;
+
+ /* Linear search for the ID of the job to use */
+ pi->jobid = 1;
+ for (job = G.job_list; job; job = job->next)
+ if (job->jobid >= pi->jobid)
+ pi->jobid = job->jobid + 1;
+
+ /* Add job to the list of running jobs */
+ jobp = &G.job_list;
+ while ((job = *jobp) != NULL)
+ jobp = &job->next;
+ job = *jobp = xmalloc(sizeof(*job));
+
+ *job = *pi; /* physical copy */
+ job->next = NULL;
+ job->cmds = xzalloc(sizeof(pi->cmds[0]) * pi->num_cmds);
+ /* Cannot copy entire pi->cmds[] vector! This causes double frees */
+ for (i = 0; i < pi->num_cmds; i++) {
+ job->cmds[i].pid = pi->cmds[i].pid;
+ /* all other fields are not used and stay zero */
+ }
+ job->cmdtext = xstrdup(get_cmdtext(pi));
+
+ if (G_interactive_fd)
+ printf("[%d] %d %s\n", job->jobid, job->cmds[0].pid, job->cmdtext);
+ G.last_jobid = job->jobid;
}
-#if ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_DOLLAR_OPS
-/* Subroutines for copying $(...) and `...` things */
-static void add_till_backquote(o_string *dest, struct in_str *input);
-/* '...' */
-static void add_till_single_quote(o_string *dest, struct in_str *input)
+static void remove_bg_job(struct pipe *pi)
{
- while (1) {
- int ch = i_getch(input);
- if (ch == EOF) {
- syntax_error_unterm_ch('\'');
- /*xfunc_die(); - redundant */
- }
- if (ch == '\'')
- return;
- o_addchr(dest, ch);
+ struct pipe *prev_pipe;
+
+ if (pi == G.job_list) {
+ G.job_list = pi->next;
+ } else {
+ prev_pipe = G.job_list;
+ while (prev_pipe->next != pi)
+ prev_pipe = prev_pipe->next;
+ prev_pipe->next = pi->next;
}
+ if (G.job_list)
+ G.last_jobid = G.job_list->jobid;
+ else
+ G.last_jobid = 0;
}
-/* "...\"...`..`...." - do we need to handle "...$(..)..." too? */
-static void add_till_double_quote(o_string *dest, struct in_str *input)
+
+/* Remove a backgrounded job */
+static void delete_finished_bg_job(struct pipe *pi)
{
- while (1) {
- int ch = i_getch(input);
- if (ch == EOF) {
- syntax_error_unterm_ch('"');
- /*xfunc_die(); - redundant */
- }
- if (ch == '"')
- return;
- if (ch == '\\') { /* \x. Copy both chars. */
- o_addchr(dest, ch);
- ch = i_getch(input);
- }
- o_addchr(dest, ch);
- if (ch == '`') {
- add_till_backquote(dest, input);
- o_addchr(dest, ch);
- continue;
- }
- //if (ch == '$') ...
- }
+ remove_bg_job(pi);
+ free_pipe(pi);
}
-/* Process `cmd` - copy contents until "`" is seen. Complicated by
- * \` quoting.
- * "Within the backquoted style of command substitution, backslash
- * shall retain its literal meaning, except when followed by: '$', '`', or '\'.
- * The search for the matching backquote shall be satisfied by the first
- * backquote found without a preceding backslash; during this search,
- * if a non-escaped backquote is encountered within a shell comment,
- * a here-document, an embedded command substitution of the $(command)
- * form, or a quoted string, undefined results occur. A single-quoted
- * or double-quoted string that begins, but does not end, within the
- * "`...`" sequence produces undefined results."
- * Example Output
- * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST
- */
-static void add_till_backquote(o_string *dest, struct in_str *input)
+#endif /* JOB */
+
+/* Check to see if any processes have exited -- if they
+ * have, figure out why and see if a job has completed */
+static int checkjobs(struct pipe *fg_pipe)
{
- while (1) {
- int ch = i_getch(input);
- if (ch == EOF) {
- syntax_error_unterm_ch('`');
- /*xfunc_die(); - redundant */
+ int attributes;
+ int status;
+#if ENABLE_HUSH_JOB
+ struct pipe *pi;
+#endif
+ pid_t childpid;
+ int rcode = 0;
+
+ debug_printf_jobs("checkjobs %p\n", fg_pipe);
+
+ attributes = WUNTRACED;
+ if (fg_pipe == NULL)
+ attributes |= WNOHANG;
+
+ errno = 0;
+#if ENABLE_HUSH_FAST
+ if (G.handled_SIGCHLD == G.count_SIGCHLD) {
+//bb_error_msg("[%d] checkjobs: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d children?:%d fg_pipe:%p",
+//getpid(), G.count_SIGCHLD, G.handled_SIGCHLD, G.we_have_children, fg_pipe);
+ /* There was neither fork nor SIGCHLD since last waitpid */
+ /* Avoid doing waitpid syscall if possible */
+ if (!G.we_have_children) {
+ errno = ECHILD;
+ return -1;
}
- if (ch == '`')
- return;
- if (ch == '\\') {
- /* \x. Copy both chars unless it is \` */
- int ch2 = i_getch(input);
- if (ch2 == EOF) {
- syntax_error_unterm_ch('`');
- /*xfunc_die(); - redundant */
- }
- if (ch2 != '`' && ch2 != '$' && ch2 != '\\')
- o_addchr(dest, ch);
- ch = ch2;
+ if (fg_pipe == NULL) { /* is WNOHANG set? */
+ /* We have children, but they did not exit
+ * or stop yet (we saw no SIGCHLD) */
+ return 0;
}
- o_addchr(dest, ch);
+ /* else: !WNOHANG, waitpid will block, can't short-circuit */
}
-}
-/* Process $(cmd) - copy contents until ")" is seen. Complicated by
- * quoting and nested ()s.
- * "With the $(command) style of command substitution, all characters
- * following the open parenthesis to the matching closing parenthesis
- * constitute the command. Any valid shell script can be used for command,
- * except a script consisting solely of redirections which produces
- * unspecified results."
- * Example Output
- * echo $(echo '(TEST)' BEST) (TEST) BEST
- * echo $(echo 'TEST)' BEST) TEST) BEST
- * echo $(echo \(\(TEST\) BEST) ((TEST) BEST
- *
- * Also adapted to eat ${var%...} and $((...)) constructs, since ... part
- * can contain arbitrary constructs, just like $(cmd).
- * In bash compat mode, it needs to also be able to stop on '}' or ':'
- * for ${var:N[:M]} parsing.
- */
-#define DOUBLE_CLOSE_CHAR_FLAG 0x80
-static int add_till_closing_bracket(o_string *dest, struct in_str *input, unsigned end_ch)
-{
- int ch;
- char dbl = end_ch & DOUBLE_CLOSE_CHAR_FLAG;
-# if ENABLE_HUSH_BASH_COMPAT
- char end_char2 = end_ch >> 8;
-# endif
- end_ch &= (DOUBLE_CLOSE_CHAR_FLAG - 1);
+#endif
+/* Do we do this right?
+ * bash-3.00# sleep 20 | false
+ * <ctrl-Z pressed>
+ * [3]+ Stopped sleep 20 | false
+ * bash-3.00# echo $?
+ * 1 <========== bg pipe is not fully done, but exitcode is already known!
+ * [hush 1.14.0: yes we do it right]
+ */
+ wait_more:
while (1) {
- ch = i_getch(input);
- if (ch == EOF) {
- syntax_error_unterm_ch(end_ch);
- /*xfunc_die(); - redundant */
+ int i;
+ int dead;
+
+#if ENABLE_HUSH_FAST
+ i = G.count_SIGCHLD;
+#endif
+ childpid = waitpid(-1, &status, attributes);
+ if (childpid <= 0) {
+ if (childpid && errno != ECHILD)
+ bb_perror_msg("waitpid");
+#if ENABLE_HUSH_FAST
+ else { /* Until next SIGCHLD, waitpid's are useless */
+ G.we_have_children = (childpid == 0);
+ G.handled_SIGCHLD = i;
+//bb_error_msg("[%d] checkjobs: waitpid returned <= 0, G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+ }
+#endif
+ break;
}
- if (ch == end_ch IF_HUSH_BASH_COMPAT( || ch == end_char2)) {
- if (!dbl)
- break;
- /* we look for closing )) of $((EXPR)) */
- if (i_peek(input) == end_ch) {
- i_getch(input); /* eat second ')' */
- break;
+ dead = WIFEXITED(status) || WIFSIGNALED(status);
+
+#if DEBUG_JOBS
+ if (WIFSTOPPED(status))
+ debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n",
+ childpid, WSTOPSIG(status), WEXITSTATUS(status));
+ if (WIFSIGNALED(status))
+ debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n",
+ childpid, WTERMSIG(status), WEXITSTATUS(status));
+ if (WIFEXITED(status))
+ debug_printf_jobs("pid %d exited, exitcode %d\n",
+ childpid, WEXITSTATUS(status));
+#endif
+ /* Were we asked to wait for fg pipe? */
+ if (fg_pipe) {
+ for (i = 0; i < fg_pipe->num_cmds; i++) {
+ debug_printf_jobs("check pid %d\n", fg_pipe->cmds[i].pid);
+ if (fg_pipe->cmds[i].pid != childpid)
+ continue;
+ if (dead) {
+ fg_pipe->cmds[i].pid = 0;
+ fg_pipe->alive_cmds--;
+ if (i == fg_pipe->num_cmds - 1) {
+ /* last process gives overall exitstatus */
+ rcode = WEXITSTATUS(status);
+ /* bash prints killer signal's name for *last*
+ * process in pipe (prints just newline for SIGINT).
+ * Mimic this. Example: "sleep 5" + (^\ or kill -QUIT)
+ */
+ if (WIFSIGNALED(status)) {
+ int sig = WTERMSIG(status);
+ printf("%s\n", sig == SIGINT ? "" : get_signame(sig));
+ /* TODO: MIPS has 128 sigs (1..128), what if sig==128 here?
+ * Maybe we need to use sig | 128? */
+ rcode = sig + 128;
+ }
+ IF_HAS_KEYWORDS(if (fg_pipe->pi_inverted) rcode = !rcode;)
+ }
+ } else {
+ fg_pipe->cmds[i].is_stopped = 1;
+ fg_pipe->stopped_cmds++;
+ }
+ debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n",
+ fg_pipe->alive_cmds, fg_pipe->stopped_cmds);
+ if (fg_pipe->alive_cmds - fg_pipe->stopped_cmds <= 0) {
+ /* All processes in fg pipe have exited or stopped */
+/* Note: *non-interactive* bash does not continue if all processes in fg pipe
+ * are stopped. Testcase: "cat | cat" in a script (not on command line!)
+ * and "killall -STOP cat" */
+ if (G_interactive_fd) {
+#if ENABLE_HUSH_JOB
+ if (fg_pipe->alive_cmds)
+ insert_bg_job(fg_pipe);
+#endif
+ return rcode;
+ }
+ if (!fg_pipe->alive_cmds)
+ return rcode;
+ }
+ /* There are still running processes in the fg pipe */
+ goto wait_more; /* do waitpid again */
}
+ /* it wasnt fg_pipe, look for process in bg pipes */
}
- o_addchr(dest, ch);
- if (ch == '(' || ch == '{') {
- ch = (ch == '(' ? ')' : '}');
- add_till_closing_bracket(dest, input, ch);
- o_addchr(dest, ch);
- continue;
- }
- if (ch == '\'') {
- add_till_single_quote(dest, input);
- o_addchr(dest, ch);
- continue;
- }
- if (ch == '"') {
- add_till_double_quote(dest, input);
- o_addchr(dest, ch);
- continue;
- }
- if (ch == '`') {
- add_till_backquote(dest, input);
- o_addchr(dest, ch);
- continue;
+
+#if ENABLE_HUSH_JOB
+ /* We asked to wait for bg or orphaned children */
+ /* No need to remember exitcode in this case */
+ for (pi = G.job_list; pi; pi = pi->next) {
+ for (i = 0; i < pi->num_cmds; i++) {
+ if (pi->cmds[i].pid == childpid)
+ goto found_pi_and_prognum;
+ }
}
- if (ch == '\\') {
- /* \x. Copy verbatim. Important for \(, \) */
- ch = i_getch(input);
- if (ch == EOF) {
- syntax_error_unterm_ch(')');
- /*xfunc_die(); - redundant */
+ /* Happens when shell is used as init process (init=/bin/sh) */
+ debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
+ continue; /* do waitpid again */
+
+ found_pi_and_prognum:
+ if (dead) {
+ /* child exited */
+ pi->cmds[i].pid = 0;
+ pi->alive_cmds--;
+ if (!pi->alive_cmds) {
+ if (G_interactive_fd)
+ printf(JOB_STATUS_FORMAT, pi->jobid,
+ "Done", pi->cmdtext);
+ delete_finished_bg_job(pi);
}
- o_addchr(dest, ch);
- continue;
+ } else {
+ /* child stopped */
+ pi->cmds[i].is_stopped = 1;
+ pi->stopped_cmds++;
}
+#endif
+ } /* while (waitpid succeeds)... */
+
+ return rcode;
+}
+
+#if ENABLE_HUSH_JOB
+static int checkjobs_and_fg_shell(struct pipe *fg_pipe)
+{
+ pid_t p;
+ int rcode = checkjobs(fg_pipe);
+ if (G_saved_tty_pgrp) {
+ /* Job finished, move the shell to the foreground */
+ p = getpgrp(); /* our process group id */
+ debug_printf_jobs("fg'ing ourself: getpgrp()=%d\n", (int)p);
+ tcsetpgrp(G_interactive_fd, p);
}
- return ch;
+ return rcode;
}
-#endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_DOLLAR_OPS */
+#endif
-/* Return code: 0 for OK, 1 for syntax error */
-#if BB_MMU
-#define parse_dollar(as_string, dest, input) \
- parse_dollar(dest, input)
-#define as_string NULL
+/* Start all the jobs, but don't wait for anything to finish.
+ * See checkjobs().
+ *
+ * Return code is normally -1, when the caller has to wait for children
+ * to finish to determine the exit status of the pipe. If the pipe
+ * is a simple builtin command, however, the action is done by the
+ * time run_pipe returns, and the exit code is provided as the
+ * return value.
+ *
+ * Returns -1 only if started some children. IOW: we have to
+ * mask out retvals of builtins etc with 0xff!
+ *
+ * The only case when we do not need to [v]fork is when the pipe
+ * is single, non-backgrounded, non-subshell command. Examples:
+ * cmd ; ... { list } ; ...
+ * cmd && ... { list } && ...
+ * cmd || ... { list } || ...
+ * If it is, then we can run cmd as a builtin, NOFORK [do we do this?],
+ * or (if SH_STANDALONE) an applet, and we can run the { list }
+ * with run_list. If it isn't one of these, we fork and exec cmd.
+ *
+ * Cases when we must fork:
+ * non-single: cmd | cmd
+ * backgrounded: cmd & { list } &
+ * subshell: ( list ) [&]
+ */
+#if !ENABLE_HUSH_MODE_X
+#define redirect_and_varexp_helper(new_env_p, old_vars_p, command, squirrel, char argv_expanded) \
+ redirect_and_varexp_helper(new_env_p, old_vars_p, command, squirrel)
#endif
-static int parse_dollar(o_string *as_string,
- o_string *dest,
- struct in_str *input)
+static int redirect_and_varexp_helper(char ***new_env_p,
+ struct variable **old_vars_p,
+ struct command *command,
+ int squirrel[3],
+ char **argv_expanded)
{
- int ch = i_peek(input); /* first character after the $ */
- unsigned char quote_mask = dest->o_escape ? 0x80 : 0;
+ /* setup_redirects acts on file descriptors, not FILEs.
+ * This is perfect for work that comes after exec().
+ * Is it really safe for inline use? Experimentally,
+ * things seem to work. */
+ int rcode = setup_redirects(command, squirrel);
+ if (rcode == 0) {
+ char **new_env = expand_assignments(command->argv, command->assignment_cnt);
+ *new_env_p = new_env;
+ dump_cmd_in_x_mode(new_env);
+ dump_cmd_in_x_mode(argv_expanded);
+ if (old_vars_p)
+ *old_vars_p = set_vars_and_save_old(new_env);
+ }
+ return rcode;
+}
+static NOINLINE int run_pipe(struct pipe *pi)
+{
+ static const char *const null_ptr = NULL;
- debug_printf_parse("parse_dollar entered: ch='%c'\n", ch);
- if (isalpha(ch)) {
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- make_var:
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- while (1) {
- debug_printf_parse(": '%c'\n", ch);
- o_addchr(dest, ch | quote_mask);
- quote_mask = 0;
- ch = i_peek(input);
- if (!isalnum(ch) && ch != '_')
- break;
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- }
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- } else if (isdigit(ch)) {
- make_one_char_var:
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- debug_printf_parse(": '%c'\n", ch);
- o_addchr(dest, ch | quote_mask);
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- } else switch (ch) {
- case '$': /* pid */
- case '!': /* last bg pid */
- case '?': /* last exit code */
- case '#': /* number of args */
- case '*': /* args */
- case '@': /* args */
- goto make_one_char_var;
- case '{': {
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ int cmd_no;
+ int next_infd;
+ struct command *command;
+ char **argv_expanded;
+ char **argv;
+ /* it is not always needed, but we aim to smaller code */
+ int squirrel[] = { -1, -1, -1 };
+ int rcode;
- ch = i_getch(input); /* eat '{' */
- nommu_addchr(as_string, ch);
+ debug_printf_exec("run_pipe start: members:%d\n", pi->num_cmds);
+ debug_enter();
- ch = i_getch(input); /* first char after '{' */
- nommu_addchr(as_string, ch);
- /* It should be ${?}, or ${#var},
- * or even ${?+subst} - operator acting on a special variable,
- * or the beginning of variable name.
- */
- if (!strchr(_SPECIAL_VARS_STR, ch) && !isalnum(ch)) { /* not one of those */
- bad_dollar_syntax:
- syntax_error_unterm_str("${name}");
- debug_printf_parse("parse_dollar return 1: unterminated ${name}\n");
- return 1;
+ /* Testcase: set -- q w e; (IFS='' echo "$*"; IFS=''; echo "$*"); echo "$*"
+ * Result should be 3 lines: q w e, qwe, q w e
+ */
+ G.ifs = get_local_var_value("IFS");
+ if (!G.ifs)
+ G.ifs = defifs;
+
+ IF_HUSH_JOB(pi->pgrp = -1;)
+ pi->stopped_cmds = 0;
+ command = &pi->cmds[0];
+ argv_expanded = NULL;
+
+ if (pi->num_cmds != 1
+ || pi->followup == PIPE_BG
+ || command->cmd_type == CMD_SUBSHELL
+ ) {
+ goto must_fork;
+ }
+
+ pi->alive_cmds = 1;
+
+ debug_printf_exec(": group:%p argv:'%s'\n",
+ command->group, command->argv ? command->argv[0] : "NONE");
+
+ if (command->group) {
+#if ENABLE_HUSH_FUNCTIONS
+ if (command->cmd_type == CMD_FUNCDEF) {
+ /* "executing" func () { list } */
+ struct function *funcp;
+
+ funcp = new_function(command->argv[0]);
+ /* funcp->name is already set to argv[0] */
+ funcp->body = command->group;
+# if !BB_MMU
+ funcp->body_as_string = command->group_as_string;
+ command->group_as_string = NULL;
+# endif
+ command->group = NULL;
+ command->argv[0] = NULL;
+ debug_printf_exec("cmd %p has child func at %p\n", command, funcp);
+ funcp->parent_cmd = command;
+ command->child_func = funcp;
+
+ debug_printf_exec("run_pipe: return EXIT_SUCCESS\n");
+ debug_leave();
+ return EXIT_SUCCESS;
}
- ch |= quote_mask;
+#endif
+ /* { list } */
+ debug_printf("non-subshell group\n");
+ rcode = 1; /* exitcode if redir failed */
+ if (setup_redirects(command, squirrel) == 0) {
+ debug_printf_exec(": run_list\n");
+ rcode = run_list(command->group) & 0xff;
+ }
+ restore_redirects(squirrel);
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ debug_leave();
+ debug_printf_exec("run_pipe: return %d\n", rcode);
+ return rcode;
+ }
+
+ argv = command->argv ? command->argv : (char **) &null_ptr;
+ {
+ const struct built_in_command *x;
+#if ENABLE_HUSH_FUNCTIONS
+ const struct function *funcp;
+#else
+ enum { funcp = 0 };
+#endif
+ char **new_env = NULL;
+ struct variable *old_vars = NULL;
- /* It's possible to just call add_till_closing_bracket() at this point.
- * However, this regresses some of our testsuite cases
- * which check invalid constructs like ${%}.
- * Oh well... let's check that the var name part is fine... */
+ if (argv[command->assignment_cnt] == NULL) {
+ /* Assignments, but no command */
+ /* Ensure redirects take effect (that is, create files).
+ * Try "a=t >file" */
+#if 0 /* A few cases in testsuite fail with this code. FIXME */
+ rcode = redirect_and_varexp_helper(&new_env, /*old_vars:*/ NULL, command, squirrel, /*argv_expanded:*/ NULL);
+ /* Set shell variables */
+ if (new_env) {
+ argv = new_env;
+ while (*argv) {
+ set_local_var(*argv, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
+ /* Do we need to flag set_local_var() errors?
+ * "assignment to readonly var" and "putenv error"
+ */
+ argv++;
+ }
+ }
+ /* Redirect error sets $? to 1. Otherwise,
+ * if evaluating assignment value set $?, retain it.
+ * Try "false; q=`exit 2`; echo $?" - should print 2: */
+ if (rcode == 0)
+ rcode = G.last_exitcode;
+ /* Exit, _skipping_ variable restoring code: */
+ goto clean_up_and_ret0;
- while (1) {
- unsigned pos;
+#else /* Older, bigger, but more correct code */
- o_addchr(dest, ch);
- debug_printf_parse(": '%c'\n", ch);
+ rcode = setup_redirects(command, squirrel);
+ restore_redirects(squirrel);
+ /* Set shell variables */
+ if (G_x_mode)
+ bb_putchar_stderr('+');
+ while (*argv) {
+ char *p = expand_string_to_string(*argv);
+ if (G_x_mode)
+ fprintf(stderr, " %s", p);
+ debug_printf_exec("set shell var:'%s'->'%s'\n",
+ *argv, p);
+ set_local_var(p, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
+ /* Do we need to flag set_local_var() errors?
+ * "assignment to readonly var" and "putenv error"
+ */
+ argv++;
+ }
+ if (G_x_mode)
+ bb_putchar_stderr('\n');
+ /* Redirect error sets $? to 1. Otherwise,
+ * if evaluating assignment value set $?, retain it.
+ * Try "false; q=`exit 2`; echo $?" - should print 2: */
+ if (rcode == 0)
+ rcode = G.last_exitcode;
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ debug_leave();
+ debug_printf_exec("run_pipe: return %d\n", rcode);
+ return rcode;
+#endif
+ }
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- if (ch == '}')
- break;
+ /* Expand the rest into (possibly) many strings each */
+ if (0) {}
+#if ENABLE_HUSH_BASH_COMPAT
+ else if (command->cmd_type == CMD_SINGLEWORD_NOGLOB) {
+ argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt);
+ }
+#endif
+ else {
+ argv_expanded = expand_strvec_to_strvec(argv + command->assignment_cnt);
+ }
- if (!isalnum(ch) && ch != '_') {
- unsigned end_ch;
- unsigned char last_ch;
- /* handle parameter expansions
- * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02
- */
- if (!strchr("%#:-=+?", ch)) /* ${var<bad_char>... */
- goto bad_dollar_syntax;
- o_addchr(dest, ch);
+ /* if someone gives us an empty string: `cmd with empty output` */
+ if (!argv_expanded[0]) {
+ free(argv_expanded);
+ debug_leave();
+ return G.last_exitcode;
+ }
- /* Eat everything until closing '}' (or ':') */
- end_ch = '}';
- if (ENABLE_HUSH_BASH_COMPAT
- && ch == ':'
- && !strchr("%#:-=+?"+3, i_peek(input))
- ) {
- /* It's ${var:N[:M]} thing */
- end_ch = '}' * 0x100 + ':';
- }
- again:
- if (!BB_MMU)
- pos = dest->length;
-#if ENABLE_HUSH_DOLLAR_OPS
- last_ch = add_till_closing_bracket(dest, input, end_ch);
-#else
-#error Simple code to only allow ${var} is not implemented
+ x = find_builtin(argv_expanded[0]);
+#if ENABLE_HUSH_FUNCTIONS
+ funcp = NULL;
+ if (!x)
+ funcp = find_function(argv_expanded[0]);
#endif
- if (as_string) {
- o_addstr(as_string, dest->data + pos);
- o_addchr(as_string, last_ch);
+ if (x || funcp) {
+ if (!funcp) {
+ if (x->b_function == builtin_exec && argv_expanded[1] == NULL) {
+ debug_printf("exec with redirects only\n");
+ rcode = setup_redirects(command, NULL);
+ goto clean_up_and_ret1;
}
-
- if (ENABLE_HUSH_BASH_COMPAT && (end_ch & 0xff00)) {
- /* close the first block: */
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- /* while parsing N from ${var:N[:M]}... */
- if ((end_ch & 0xff) == last_ch) {
- /* ...got ':' - parse the rest */
- end_ch = '}';
- goto again;
- }
- /* ...got '}', not ':' - it's ${var:N}! emulate :999999999 */
- o_addstr(dest, "999999999");
+ }
+ rcode = redirect_and_varexp_helper(&new_env, &old_vars, command, squirrel, argv_expanded);
+ if (rcode == 0) {
+ if (!funcp) {
+ debug_printf_exec(": builtin '%s' '%s'...\n",
+ x->b_cmd, argv_expanded[1]);
+ rcode = x->b_function(argv_expanded) & 0xff;
+ fflush_all();
}
- break;
+#if ENABLE_HUSH_FUNCTIONS
+ else {
+# if ENABLE_HUSH_LOCAL
+ struct variable **sv;
+ sv = G.shadowed_vars_pp;
+ G.shadowed_vars_pp = &old_vars;
+# endif
+ debug_printf_exec(": function '%s' '%s'...\n",
+ funcp->name, argv_expanded[1]);
+ rcode = run_function(funcp, argv_expanded) & 0xff;
+# if ENABLE_HUSH_LOCAL
+ G.shadowed_vars_pp = sv;
+# endif
+ }
+#endif
}
+ clean_up_and_ret:
+ unset_vars(new_env);
+ add_vars(old_vars);
+/* clean_up_and_ret0: */
+ restore_redirects(squirrel);
+ clean_up_and_ret1:
+ free(argv_expanded);
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ debug_leave();
+ debug_printf_exec("run_pipe return %d\n", rcode);
+ return rcode;
}
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- break;
- }
-#if ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_TICK
- case '(': {
- unsigned pos;
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
-# if ENABLE_SH_MATH_SUPPORT
- if (i_peek(input) == '(') {
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- o_addchr(dest, /*quote_mask |*/ '+');
- if (!BB_MMU)
- pos = dest->length;
- add_till_closing_bracket(dest, input, ')' | DOUBLE_CLOSE_CHAR_FLAG);
- if (as_string) {
- o_addstr(as_string, dest->data + pos);
- o_addchr(as_string, ')');
- o_addchr(as_string, ')');
+ if (ENABLE_FEATURE_SH_STANDALONE) {
+ int n = find_applet_by_name(argv_expanded[0]);
+ if (n >= 0 && APPLET_IS_NOFORK(n)) {
+ rcode = redirect_and_varexp_helper(&new_env, &old_vars, command, squirrel, argv_expanded);
+ if (rcode == 0) {
+ debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
+ argv_expanded[0], argv_expanded[1]);
+ rcode = run_nofork_applet(n, argv_expanded);
+ }
+ goto clean_up_and_ret;
}
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- break;
}
-# endif
-# if ENABLE_HUSH_TICK
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- o_addchr(dest, quote_mask | '`');
- if (!BB_MMU)
- pos = dest->length;
- add_till_closing_bracket(dest, input, ')');
- if (as_string) {
- o_addstr(as_string, dest->data + pos);
- o_addchr(as_string, ')');
- }
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
-# endif
- break;
+ /* It is neither builtin nor applet. We must fork. */
}
+
+ must_fork:
+ /* NB: argv_expanded may already be created, and that
+ * might include `cmd` runs! Do not rerun it! We *must*
+ * use argv_expanded if it's non-NULL */
+
+ /* Going to fork a child per each pipe member */
+ pi->alive_cmds = 0;
+ next_infd = 0;
+
+ cmd_no = 0;
+ while (cmd_no < pi->num_cmds) {
+ struct fd_pair pipefds;
+#if !BB_MMU
+ volatile nommu_save_t nommu_save;
+ nommu_save.new_env = NULL;
+ nommu_save.old_vars = NULL;
+ nommu_save.argv = NULL;
+ nommu_save.argv_from_re_execing = NULL;
#endif
- case '_':
- ch = i_getch(input);
- nommu_addchr(as_string, ch);
- ch = i_peek(input);
- if (isalnum(ch)) { /* it's $_name or $_123 */
- ch = '_';
- goto make_var;
+ command = &pi->cmds[cmd_no];
+ cmd_no++;
+ if (command->argv) {
+ debug_printf_exec(": pipe member '%s' '%s'...\n",
+ command->argv[0], command->argv[1]);
+ } else {
+ debug_printf_exec(": pipe member with no argv\n");
}
- /* else: it's $_ */
- /* TODO: $_ and $-: */
- /* $_ Shell or shell script name; or last argument of last command
- * (if last command wasn't a pipe; if it was, bash sets $_ to "");
- * but in command's env, set to full pathname used to invoke it */
- /* $- Option flags set by set builtin or shell options (-i etc) */
- default:
- o_addQchr(dest, '$');
- }
- debug_printf_parse("parse_dollar return 0\n");
- return 0;
-#undef as_string
-}
-#if BB_MMU
-#define parse_stream_dquoted(as_string, dest, input, dquote_end) \
- parse_stream_dquoted(dest, input, dquote_end)
-#define as_string NULL
+ /* pipes are inserted between pairs of commands */
+ pipefds.rd = 0;
+ pipefds.wr = 1;
+ if (cmd_no < pi->num_cmds)
+ xpiped_pair(pipefds);
+
+ command->pid = BB_MMU ? fork() : vfork();
+ if (!command->pid) { /* child */
+#if ENABLE_HUSH_JOB
+ disable_restore_tty_pgrp_on_exit();
+ CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
+
+ /* Every child adds itself to new process group
+ * with pgid == pid_of_first_child_in_pipe */
+ if (G.run_list_level == 1 && G_interactive_fd) {
+ pid_t pgrp;
+ pgrp = pi->pgrp;
+ if (pgrp < 0) /* true for 1st process only */
+ pgrp = getpid();
+ if (setpgid(0, pgrp) == 0
+ && pi->followup != PIPE_BG
+ && G_saved_tty_pgrp /* we have ctty */
+ ) {
+ /* We do it in *every* child, not just first,
+ * to avoid races */
+ tcsetpgrp(G_interactive_fd, pgrp);
+ }
+ }
#endif
-static int parse_stream_dquoted(o_string *as_string,
- o_string *dest,
- struct in_str *input,
- int dquote_end)
-{
- int ch;
- int next;
+ if (pi->alive_cmds == 0 && pi->followup == PIPE_BG) {
+ /* 1st cmd in backgrounded pipe
+ * should have its stdin /dev/null'ed */
+ close(0);
+ if (open(bb_dev_null, O_RDONLY))
+ xopen("/", O_RDONLY);
+ } else {
+ xmove_fd(next_infd, 0);
+ }
+ xmove_fd(pipefds.wr, 1);
+ if (pipefds.rd > 1)
+ close(pipefds.rd);
+ /* Like bash, explicit redirects override pipes,
+ * and the pipe fd is available for dup'ing. */
+ if (setup_redirects(command, NULL))
+ _exit(1);
- again:
- ch = i_getch(input);
- if (ch != EOF)
- nommu_addchr(as_string, ch);
- if (ch == dquote_end) { /* may be only '"' or EOF */
- if (dest->o_assignment == NOT_ASSIGNMENT)
- dest->o_escape ^= 1;
- debug_printf_parse("parse_stream_dquoted return 0\n");
- return 0;
- }
- /* note: can't move it above ch == dquote_end check! */
- if (ch == EOF) {
- syntax_error_unterm_ch('"');
- /*xfunc_die(); - redundant */
- }
- next = '\0';
- if (ch != '\n') {
- next = i_peek(input);
- }
- debug_printf_parse("\" ch=%c (%d) escape=%d\n",
- ch, ch, dest->o_escape);
- if (ch == '\\') {
- if (next == EOF) {
- syntax_error("\\<eof>");
- xfunc_die();
+ /* Restore default handlers just prior to exec */
+ /*signal(SIGCHLD, SIG_DFL); - so far we don't have any handlers */
+
+ /* Stores to nommu_save list of env vars putenv'ed
+ * (NOMMU, on MMU we don't need that) */
+ /* cast away volatility... */
+ pseudo_exec((nommu_save_t*) &nommu_save, command, argv_expanded);
+ /* pseudo_exec() does not return */
}
- /* bash:
- * "The backslash retains its special meaning [in "..."]
- * only when followed by one of the following characters:
- * $, `, ", \, or <newline>. A double quote may be quoted
- * within double quotes by preceding it with a backslash."
- */
- if (strchr("$`\"\\\n", next) != NULL) {
- ch = i_getch(input);
- if (ch != '\n') {
- o_addqchr(dest, ch);
- nommu_addchr(as_string, ch);
- }
+
+ /* parent or error */
+#if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] fork in run_pipe: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+#endif
+ enable_restore_tty_pgrp_on_exit();
+#if !BB_MMU
+ /* Clean up after vforked child */
+ free(nommu_save.argv);
+ free(nommu_save.argv_from_re_execing);
+ unset_vars(nommu_save.new_env);
+ add_vars(nommu_save.old_vars);
+#endif
+ free(argv_expanded);
+ argv_expanded = NULL;
+ if (command->pid < 0) { /* [v]fork failed */
+ /* Clearly indicate, was it fork or vfork */
+ bb_perror_msg(BB_MMU ? "vfork"+1 : "vfork");
} else {
- o_addqchr(dest, '\\');
- nommu_addchr(as_string, '\\');
- }
- goto again;
- }
- if (ch == '$') {
- if (parse_dollar(as_string, dest, input) != 0) {
- debug_printf_parse("parse_stream_dquoted return 1: "
- "parse_dollar returned non-0\n");
- return 1;
+ pi->alive_cmds++;
+#if ENABLE_HUSH_JOB
+ /* Second and next children need to know pid of first one */
+ if (pi->pgrp < 0)
+ pi->pgrp = command->pid;
+#endif
}
- goto again;
- }
-#if ENABLE_HUSH_TICK
- if (ch == '`') {
- //unsigned pos = dest->length;
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- o_addchr(dest, 0x80 | '`');
- add_till_backquote(dest, input);
- o_addchr(dest, SPECIAL_VAR_SYMBOL);
- //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
- goto again;
+
+ if (cmd_no > 1)
+ close(next_infd);
+ if (cmd_no < pi->num_cmds)
+ close(pipefds.wr);
+ /* Pass read (output) pipe end to next iteration */
+ next_infd = pipefds.rd;
}
-#endif
- o_addQchr(dest, ch);
- if (ch == '='
- && (dest->o_assignment == MAYBE_ASSIGNMENT
- || dest->o_assignment == WORD_IS_KEYWORD)
- && is_well_formed_var_name(dest->data, '=')
- ) {
- dest->o_assignment = DEFINITELY_ASSIGNMENT;
+
+ if (!pi->alive_cmds) {
+ debug_leave();
+ debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n");
+ return 1;
}
- goto again;
-#undef as_string
+
+ debug_leave();
+ debug_printf_exec("run_pipe return -1 (%u children started)\n", pi->alive_cmds);
+ return -1;
}
-/*
- * Scan input until EOF or end_trigger char.
- * Return a list of pipes to execute, or NULL on EOF
- * or if end_trigger character is met.
- * On syntax error, exit is shell is not interactive,
- * reset parsing machinery and start parsing anew,
- * or return ERR_PTR.
- */
-static struct pipe *parse_stream(char **pstring,
- struct in_str *input,
- int end_trigger)
+#ifndef debug_print_tree
+static void debug_print_tree(struct pipe *pi, int lvl)
{
- struct parse_context ctx;
- o_string dest = NULL_O_STRING;
- int is_in_dquote;
- int heredoc_cnt;
-
- /* Double-quote state is handled in the state variable is_in_dquote.
- * A single-quote triggers a bypass of the main loop until its mate is
- * found. When recursing, quote state is passed in via dest->o_escape.
- */
- debug_printf_parse("parse_stream entered, end_trigger='%c'\n",
- end_trigger ? end_trigger : 'X');
- debug_enter();
-
- /* If very first arg is "" or '', dest.data may end up NULL.
- * Preventing this: */
- o_addchr(&dest, '\0');
- dest.length = 0;
-
- G.ifs = get_local_var_value("IFS");
- if (G.ifs == NULL)
- G.ifs = defifs;
+ static const char *const PIPE[] = {
+ [PIPE_SEQ] = "SEQ",
+ [PIPE_AND] = "AND",
+ [PIPE_OR ] = "OR" ,
+ [PIPE_BG ] = "BG" ,
+ };
+ static const char *RES[] = {
+ [RES_NONE ] = "NONE" ,
+# if ENABLE_HUSH_IF
+ [RES_IF ] = "IF" ,
+ [RES_THEN ] = "THEN" ,
+ [RES_ELIF ] = "ELIF" ,
+ [RES_ELSE ] = "ELSE" ,
+ [RES_FI ] = "FI" ,
+# endif
+# if ENABLE_HUSH_LOOPS
+ [RES_FOR ] = "FOR" ,
+ [RES_WHILE] = "WHILE",
+ [RES_UNTIL] = "UNTIL",
+ [RES_DO ] = "DO" ,
+ [RES_DONE ] = "DONE" ,
+# endif
+# if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
+ [RES_IN ] = "IN" ,
+# endif
+# if ENABLE_HUSH_CASE
+ [RES_CASE ] = "CASE" ,
+ [RES_CASE_IN ] = "CASE_IN" ,
+ [RES_MATCH] = "MATCH",
+ [RES_CASE_BODY] = "CASE_BODY",
+ [RES_ESAC ] = "ESAC" ,
+# endif
+ [RES_XXXX ] = "XXXX" ,
+ [RES_SNTX ] = "SNTX" ,
+ };
+ static const char *const CMDTYPE[] = {
+ "{}",
+ "()",
+ "[noglob]",
+# if ENABLE_HUSH_FUNCTIONS
+ "func()",
+# endif
+ };
- reset:
-#if ENABLE_HUSH_INTERACTIVE
- input->promptmode = 0; /* PS1 */
-#endif
- /* dest.o_assignment = MAYBE_ASSIGNMENT; - already is */
- initialize_context(&ctx);
- is_in_dquote = 0;
- heredoc_cnt = 0;
- while (1) {
- const char *is_ifs;
- const char *is_special;
- int ch;
- int next;
- int redir_fd;
- redir_type redir_style;
+ int pin, prn;
- if (is_in_dquote) {
- /* dest.o_quoted = 1; - already is (see below) */
- if (parse_stream_dquoted(&ctx.as_string, &dest, input, '"')) {
- goto parse_error;
- }
- /* We reached closing '"' */
- is_in_dquote = 0;
- }
- ch = i_getch(input);
- debug_printf_parse(": ch=%c (%d) escape=%d\n",
- ch, ch, dest.o_escape);
- if (ch == EOF) {
- struct pipe *pi;
+ pin = 0;
+ while (pi) {
+ fprintf(stderr, "%*spipe %d res_word=%s followup=%d %s\n", lvl*2, "",
+ pin, RES[pi->res_word], pi->followup, PIPE[pi->followup]);
+ prn = 0;
+ while (prn < pi->num_cmds) {
+ struct command *command = &pi->cmds[prn];
+ char **argv = command->argv;
- if (heredoc_cnt) {
- syntax_error_unterm_str("here document");
- goto parse_error;
+ fprintf(stderr, "%*s cmd %d assignment_cnt:%d",
+ lvl*2, "", prn,
+ command->assignment_cnt);
+ if (command->group) {
+ fprintf(stderr, " group %s: (argv=%p)%s%s\n",
+ CMDTYPE[command->cmd_type],
+ argv
+# if !BB_MMU
+ , " group_as_string:", command->group_as_string
+# else
+ , "", ""
+# endif
+ );
+ debug_print_tree(command->group, lvl+1);
+ prn++;
+ continue;
}
- /* end_trigger == '}' case errors out earlier,
- * checking only ')' */
- if (end_trigger == ')') {
- syntax_error_unterm_ch('('); /* exits */
- /* goto parse_error; */
+ if (argv) while (*argv) {
+ fprintf(stderr, " '%s'", *argv);
+ argv++;
}
+ fprintf(stderr, "\n");
+ prn++;
+ }
+ pi = pi->next;
+ pin++;
+ }
+}
+#endif /* debug_print_tree */
- if (done_word(&dest, &ctx)) {
- goto parse_error;
- }
- o_free(&dest);
- done_pipe(&ctx, PIPE_SEQ);
- pi = ctx.list_head;
- /* If we got nothing... */
- /* (this makes bare "&" cmd a no-op.
- * bash says: "syntax error near unexpected token '&'") */
- if (pi->num_cmds == 0
- IF_HAS_KEYWORDS( && pi->res_word == RES_NONE)
- ) {
- free_pipe_list(pi);
- pi = NULL;
- }
-#if !BB_MMU
- debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
- if (pstring)
- *pstring = ctx.as_string.data;
- else
- o_free_unsafe(&ctx.as_string);
+/* NB: called by pseudo_exec, and therefore must not modify any
+ * global data until exec/_exit (we can be a child after vfork!) */
+static int run_list(struct pipe *pi)
+{
+#if ENABLE_HUSH_CASE
+ char *case_word = NULL;
+#endif
+#if ENABLE_HUSH_LOOPS
+ struct pipe *loop_top = NULL;
+ char **for_lcur = NULL;
+ char **for_list = NULL;
+#endif
+ smallint last_followup;
+ smalluint rcode;
+#if ENABLE_HUSH_IF || ENABLE_HUSH_CASE
+ smalluint cond_code = 0;
+#else
+ enum { cond_code = 0 };
+#endif
+#if HAS_KEYWORDS
+ smallint rword; /* RES_foo */
+ smallint last_rword; /* ditto */
#endif
- debug_leave();
- debug_printf_parse("parse_stream return %p\n", pi);
- return pi;
- }
- nommu_addchr(&ctx.as_string, ch);
- next = '\0';
- if (ch != '\n')
- next = i_peek(input);
+ debug_printf_exec("run_list start lvl %d\n", G.run_list_level);
+ debug_enter();
- is_special = "{}<>;&|()#'" /* special outside of "str" */
- "\\$\"" IF_HUSH_TICK("`"); /* always special */
- /* Are { and } special here? */
- if (ctx.command->argv /* word [word]{... - non-special */
- || dest.length /* word{... - non-special */
- || dest.o_quoted /* ""{... - non-special */
- || (next != ';' /* }; - special */
- && next != ')' /* }) - special */
- && next != '&' /* }& and }&& ... - special */
- && next != '|' /* }|| ... - special */
- && !strchr(G.ifs, next) /* {word - non-special */
- )
- ) {
- /* They are not special, skip "{}" */
- is_special += 2;
+#if ENABLE_HUSH_LOOPS
+ /* Check syntax for "for" */
+ for (struct pipe *cpipe = pi; cpipe; cpipe = cpipe->next) {
+ if (cpipe->res_word != RES_FOR && cpipe->res_word != RES_IN)
+ continue;
+ /* current word is FOR or IN (BOLD in comments below) */
+ if (cpipe->next == NULL) {
+ syntax_error("malformed for");
+ debug_leave();
+ debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
+ return 1;
}
- is_special = strchr(is_special, ch);
- is_ifs = strchr(G.ifs, ch);
-
- if (!is_special && !is_ifs) { /* ordinary char */
- ordinary_char:
- o_addQchr(&dest, ch);
- if ((dest.o_assignment == MAYBE_ASSIGNMENT
- || dest.o_assignment == WORD_IS_KEYWORD)
- && ch == '='
- && is_well_formed_var_name(dest.data, '=')
- ) {
- dest.o_assignment = DEFINITELY_ASSIGNMENT;
- }
+ /* "FOR v; do ..." and "for v IN a b; do..." are ok */
+ if (cpipe->next->res_word == RES_DO)
continue;
+ /* next word is not "do". It must be "in" then ("FOR v in ...") */
+ if (cpipe->res_word == RES_IN /* "for v IN a b; not_do..."? */
+ || cpipe->next->res_word != RES_IN /* FOR v not_do_and_not_in..."? */
+ ) {
+ syntax_error("malformed for");
+ debug_leave();
+ debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
+ return 1;
}
-
- if (is_ifs) {
- if (done_word(&dest, &ctx)) {
- goto parse_error;
- }
- if (ch == '\n') {
-#if ENABLE_HUSH_CASE
- /* "case ... in <newline> word) ..." -
- * newlines are ignored (but ';' wouldn't be) */
- if (ctx.command->argv == NULL
- && ctx.ctx_res_w == RES_MATCH
- ) {
- continue;
- }
+ }
#endif
- /* Treat newline as a command separator. */
- done_pipe(&ctx, PIPE_SEQ);
- debug_printf_parse("heredoc_cnt:%d\n", heredoc_cnt);
- if (heredoc_cnt) {
- if (fetch_heredocs(heredoc_cnt, &ctx, input)) {
- goto parse_error;
- }
- heredoc_cnt = 0;
- }
- dest.o_assignment = MAYBE_ASSIGNMENT;
- ch = ';';
- /* note: if (is_ifs) continue;
- * will still trigger for us */
- }
- }
- /* "cmd}" or "cmd }..." without semicolon or &:
- * } is an ordinary char in this case, even inside { cmd; }
- * Pathological example: { ""}; } should exec "}" cmd
- */
- if (ch == '}') {
- if (!IS_NULL_CMD(ctx.command) /* cmd } */
- || dest.length != 0 /* word} */
- || dest.o_quoted /* ""} */
- ) {
- goto ordinary_char;
- }
- if (!IS_NULL_PIPE(ctx.pipe)) /* cmd | } */
- goto skip_end_trigger;
- /* else: } does terminate a group */
- }
+ /* Past this point, all code paths should jump to ret: label
+ * in order to return, no direct "return" statements please.
+ * This helps to ensure that no memory is leaked. */
- if (end_trigger && end_trigger == ch
- && (ch != ';' || heredoc_cnt == 0)
-#if ENABLE_HUSH_CASE
- && (ch != ')'
- || ctx.ctx_res_w != RES_MATCH
- || (!dest.o_quoted && strcmp(dest.data, "esac") == 0)
- )
+#if ENABLE_HUSH_JOB
+ G.run_list_level++;
#endif
- ) {
- if (heredoc_cnt) {
- /* This is technically valid:
- * { cat <<HERE; }; echo Ok
- * heredoc
- * heredoc
- * HERE
- * but we don't support this.
- * We require heredoc to be in enclosing {}/(),
- * if any.
- */
- syntax_error_unterm_str("here document");
- goto parse_error;
- }
- if (done_word(&dest, &ctx)) {
- goto parse_error;
- }
- done_pipe(&ctx, PIPE_SEQ);
- dest.o_assignment = MAYBE_ASSIGNMENT;
- /* Do we sit outside of any if's, loops or case's? */
- if (!HAS_KEYWORDS
- IF_HAS_KEYWORDS(|| (ctx.ctx_res_w == RES_NONE && ctx.old_flag == 0))
- ) {
- o_free(&dest);
-#if !BB_MMU
- debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
- if (pstring)
- *pstring = ctx.as_string.data;
- else
- o_free_unsafe(&ctx.as_string);
+
+#if HAS_KEYWORDS
+ rword = RES_NONE;
+ last_rword = RES_XXXX;
#endif
- debug_leave();
- debug_printf_parse("parse_stream return %p: "
- "end_trigger char found\n",
- ctx.list_head);
- return ctx.list_head;
- }
- }
- skip_end_trigger:
- if (is_ifs)
- continue;
+ last_followup = PIPE_SEQ;
+ rcode = G.last_exitcode;
- /* Catch <, > before deciding whether this word is
- * an assignment. a=1 2>z b=2: b=2 is still assignment */
- switch (ch) {
- case '>':
- redir_fd = redirect_opt_num(&dest);
- if (done_word(&dest, &ctx)) {
- goto parse_error;
- }
- redir_style = REDIRECT_OVERWRITE;
- if (next == '>') {
- redir_style = REDIRECT_APPEND;
- ch = i_getch(input);
- nommu_addchr(&ctx.as_string, ch);
- }
-#if 0
- else if (next == '(') {
- syntax_error(">(process) not supported");
- goto parse_error;
- }
+ /* Go through list of pipes, (maybe) executing them. */
+ for (; pi; pi = IF_HUSH_LOOPS(rword == RES_DONE ? loop_top : ) pi->next) {
+ if (G.flag_SIGINT)
+ break;
+
+ IF_HAS_KEYWORDS(rword = pi->res_word;)
+ debug_printf_exec(": rword=%d cond_code=%d last_rword=%d\n",
+ rword, cond_code, last_rword);
+#if ENABLE_HUSH_LOOPS
+ if ((rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR)
+ && loop_top == NULL /* avoid bumping G.depth_of_loop twice */
+ ) {
+ /* start of a loop: remember where loop starts */
+ loop_top = pi;
+ G.depth_of_loop++;
+ }
#endif
- if (parse_redirect(&ctx, redir_fd, redir_style, input))
- goto parse_error;
- continue; /* back to top of while (1) */
- case '<':
- redir_fd = redirect_opt_num(&dest);
- if (done_word(&dest, &ctx)) {
- goto parse_error;
+ /* Still in the same "if...", "then..." or "do..." branch? */
+ if (IF_HAS_KEYWORDS(rword == last_rword &&) 1) {
+ if ((rcode == 0 && last_followup == PIPE_OR)
+ || (rcode != 0 && last_followup == PIPE_AND)
+ ) {
+ /* It is "<true> || CMD" or "<false> && CMD"
+ * and we should not execute CMD */
+ debug_printf_exec("skipped cmd because of || or &&\n");
+ last_followup = pi->followup;
+ continue;
}
- redir_style = REDIRECT_INPUT;
- if (next == '<') {
- redir_style = REDIRECT_HEREDOC;
- heredoc_cnt++;
- debug_printf_parse("++heredoc_cnt=%d\n", heredoc_cnt);
- ch = i_getch(input);
- nommu_addchr(&ctx.as_string, ch);
- } else if (next == '>') {
- redir_style = REDIRECT_IO;
- ch = i_getch(input);
- nommu_addchr(&ctx.as_string, ch);
+ }
+ last_followup = pi->followup;
+ IF_HAS_KEYWORDS(last_rword = rword;)
+#if ENABLE_HUSH_IF
+ if (cond_code) {
+ if (rword == RES_THEN) {
+ /* if false; then ... fi has exitcode 0! */
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ /* "if <false> THEN cmd": skip cmd */
+ continue;
}
-#if 0
- else if (next == '(') {
- syntax_error("<(process) not supported");
- goto parse_error;
+ } else {
+ if (rword == RES_ELSE || rword == RES_ELIF) {
+ /* "if <true> then ... ELSE/ELIF cmd":
+ * skip cmd and all following ones */
+ break;
}
-#endif
- if (parse_redirect(&ctx, redir_fd, redir_style, input))
- goto parse_error;
- continue; /* back to top of while (1) */
- }
-
- if (dest.o_assignment == MAYBE_ASSIGNMENT
- /* check that we are not in word in "a=1 2>word b=1": */
- && !ctx.pending_redirect
- ) {
- /* ch is a special char and thus this word
- * cannot be an assignment */
- dest.o_assignment = NOT_ASSIGNMENT;
}
+#endif
+#if ENABLE_HUSH_LOOPS
+ if (rword == RES_FOR) { /* && pi->num_cmds - always == 1 */
+ if (!for_lcur) {
+ /* first loop through for */
- /* Note: nommu_addchr(&ctx.as_string, ch) is already done */
+ static const char encoded_dollar_at[] ALIGN1 = {
+ SPECIAL_VAR_SYMBOL, '@' | 0x80, SPECIAL_VAR_SYMBOL, '\0'
+ }; /* encoded representation of "$@" */
+ static const char *const encoded_dollar_at_argv[] = {
+ encoded_dollar_at, NULL
+ }; /* argv list with one element: "$@" */
+ char **vals;
- switch (ch) {
- case '#':
- if (dest.length == 0) {
- while (1) {
- ch = i_peek(input);
- if (ch == EOF || ch == '\n')
+ vals = (char**)encoded_dollar_at_argv;
+ if (pi->next->res_word == RES_IN) {
+ /* if no variable values after "in" we skip "for" */
+ if (!pi->next->cmds[0].argv) {
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n");
break;
- i_getch(input);
- /* note: we do not add it to &ctx.as_string */
- }
- nommu_addchr(&ctx.as_string, '\n');
- } else {
- o_addQchr(&dest, ch);
- }
- break;
- case '\\':
- if (next == EOF) {
- syntax_error("\\<eof>");
- xfunc_die();
- }
- ch = i_getch(input);
- if (ch != '\n') {
- o_addchr(&dest, '\\');
- /*nommu_addchr(&ctx.as_string, '\\'); - already done */
- o_addchr(&dest, ch);
- nommu_addchr(&ctx.as_string, ch);
- /* Example: echo Hello \2>file
- * we need to know that word 2 is quoted */
- dest.o_quoted = 1;
+ }
+ vals = pi->next->cmds[0].argv;
+ } /* else: "for var; do..." -> assume "$@" list */
+ /* create list of variable values */
+ debug_print_strings("for_list made from", vals);
+ for_list = expand_strvec_to_strvec(vals);
+ for_lcur = for_list;
+ debug_print_strings("for_list", for_list);
}
-#if !BB_MMU
- else {
- /* It's "\<newline>". Remove trailing '\' from ctx.as_string */
- ctx.as_string.data[--ctx.as_string.length] = '\0';
+ if (!*for_lcur) {
+ /* "for" loop is over, clean up */
+ free(for_list);
+ for_list = NULL;
+ for_lcur = NULL;
+ break;
}
+ /* Insert next value from for_lcur */
+ /* note: *for_lcur already has quotes removed, $var expanded, etc */
+ set_local_var(xasprintf("%s=%s", pi->cmds[0].argv[0], *for_lcur++), /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
+ continue;
+ }
+ if (rword == RES_IN) {
+ continue; /* "for v IN list;..." - "in" has no cmds anyway */
+ }
+ if (rword == RES_DONE) {
+ continue; /* "done" has no cmds too */
+ }
#endif
- break;
- case '$':
- if (parse_dollar(&ctx.as_string, &dest, input) != 0) {
- debug_printf_parse("parse_stream parse error: "
- "parse_dollar returned non-0\n");
- goto parse_error;
- }
- break;
- case '\'':
- dest.o_quoted = 1;
- while (1) {
- ch = i_getch(input);
- if (ch == EOF) {
- syntax_error_unterm_ch('\'');
- /*xfunc_die(); - redundant */
- }
- nommu_addchr(&ctx.as_string, ch);
- if (ch == '\'')
+#if ENABLE_HUSH_CASE
+ if (rword == RES_CASE) {
+ case_word = expand_strvec_to_string(pi->cmds->argv);
+ continue;
+ }
+ if (rword == RES_MATCH) {
+ char **argv;
+
+ if (!case_word) /* "case ... matched_word) ... WORD)": we executed selected branch, stop */
+ break;
+ /* all prev words didn't match, does this one match? */
+ argv = pi->cmds->argv;
+ while (*argv) {
+ char *pattern = expand_string_to_string(*argv);
+ /* TODO: which FNM_xxx flags to use? */
+ cond_code = (fnmatch(pattern, case_word, /*flags:*/ 0) != 0);
+ free(pattern);
+ if (cond_code == 0) { /* match! we will execute this branch */
+ free(case_word); /* make future "word)" stop */
+ case_word = NULL;
break;
- o_addqchr(&dest, ch);
+ }
+ argv++;
}
- break;
- case '"':
- dest.o_quoted = 1;
- is_in_dquote ^= 1; /* invert */
- if (dest.o_assignment == NOT_ASSIGNMENT)
- dest.o_escape ^= 1;
- break;
-#if ENABLE_HUSH_TICK
- case '`': {
- unsigned pos;
-
- o_addchr(&dest, SPECIAL_VAR_SYMBOL);
- o_addchr(&dest, '`');
- pos = dest.length;
- add_till_backquote(&dest, input);
-# if !BB_MMU
- o_addstr(&ctx.as_string, dest.data + pos);
- o_addchr(&ctx.as_string, '`');
-# endif
- o_addchr(&dest, SPECIAL_VAR_SYMBOL);
- //debug_printf_subst("SUBST RES3 '%s'\n", dest.data + pos);
- break;
+ continue;
+ }
+ if (rword == RES_CASE_BODY) { /* inside of a case branch */
+ if (cond_code != 0)
+ continue; /* not matched yet, skip this pipe */
}
#endif
- case ';':
-#if ENABLE_HUSH_CASE
- case_semi:
+ /* Just pressing <enter> in shell should check for jobs.
+ * OTOH, in non-interactive shell this is useless
+ * and only leads to extra job checks */
+ if (pi->num_cmds == 0) {
+ if (G_interactive_fd)
+ goto check_jobs_and_continue;
+ continue;
+ }
+
+ /* After analyzing all keywords and conditions, we decided
+ * to execute this pipe. NB: have to do checkjobs(NULL)
+ * after run_pipe to collect any background children,
+ * even if list execution is to be stopped. */
+ debug_printf_exec(": run_pipe with %d members\n", pi->num_cmds);
+ {
+ int r;
+#if ENABLE_HUSH_LOOPS
+ G.flag_break_continue = 0;
+#endif
+ rcode = r = run_pipe(pi); /* NB: rcode is a smallint */
+ if (r != -1) {
+ /* We ran a builtin, function, or group.
+ * rcode is already known
+ * and we don't need to wait for anything. */
+ G.last_exitcode = rcode;
+ debug_printf_exec(": builtin/func exitcode %d\n", rcode);
+ check_and_run_traps(0);
+#if ENABLE_HUSH_LOOPS
+ /* Was it "break" or "continue"? */
+ if (G.flag_break_continue) {
+ smallint fbc = G.flag_break_continue;
+ /* We might fall into outer *loop*,
+ * don't want to break it too */
+ if (loop_top) {
+ G.depth_break_continue--;
+ if (G.depth_break_continue == 0)
+ G.flag_break_continue = 0;
+ /* else: e.g. "continue 2" should *break* once, *then* continue */
+ } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */
+ if (G.depth_break_continue != 0 || fbc == BC_BREAK)
+ goto check_jobs_and_break;
+ /* "continue": simulate end of loop */
+ rword = RES_DONE;
+ continue;
+ }
#endif
- if (done_word(&dest, &ctx)) {
- goto parse_error;
- }
- done_pipe(&ctx, PIPE_SEQ);
-#if ENABLE_HUSH_CASE
- /* Eat multiple semicolons, detect
- * whether it means something special */
- while (1) {
- ch = i_peek(input);
- if (ch != ';')
- break;
- ch = i_getch(input);
- nommu_addchr(&ctx.as_string, ch);
- if (ctx.ctx_res_w == RES_CASE_BODY) {
- ctx.ctx_dsemicolon = 1;
- ctx.ctx_res_w = RES_MATCH;
+#if ENABLE_HUSH_FUNCTIONS
+ if (G.flag_return_in_progress == 1) {
+ /* same as "goto check_jobs_and_break" */
+ checkjobs(NULL);
break;
}
- }
#endif
- new_cmd:
- /* We just finished a cmd. New one may start
- * with an assignment */
- dest.o_assignment = MAYBE_ASSIGNMENT;
- break;
- case '&':
- if (done_word(&dest, &ctx)) {
- goto parse_error;
- }
- if (next == '&') {
- ch = i_getch(input);
- nommu_addchr(&ctx.as_string, ch);
- done_pipe(&ctx, PIPE_AND);
- } else {
- done_pipe(&ctx, PIPE_BG);
- }
- goto new_cmd;
- case '|':
- if (done_word(&dest, &ctx)) {
- goto parse_error;
- }
-#if ENABLE_HUSH_CASE
- if (ctx.ctx_res_w == RES_MATCH)
- break; /* we are in case's "word | word)" */
+ } else if (pi->followup == PIPE_BG) {
+ /* What does bash do with attempts to background builtins? */
+ /* even bash 3.2 doesn't do that well with nested bg:
+ * try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
+ * I'm NOT treating inner &'s as jobs */
+ check_and_run_traps(0);
+#if ENABLE_HUSH_JOB
+ if (G.run_list_level == 1)
+ insert_bg_job(pi);
#endif
- if (next == '|') { /* || */
- ch = i_getch(input);
- nommu_addchr(&ctx.as_string, ch);
- done_pipe(&ctx, PIPE_OR);
+ /* Last command's pid goes to $! */
+ G.last_bg_pid = pi->cmds[pi->num_cmds - 1].pid;
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n");
} else {
- /* we could pick up a file descriptor choice here
- * with redirect_opt_num(), but bash doesn't do it.
- * "echo foo 2| cat" yields "foo 2". */
- done_command(&ctx);
-#if !BB_MMU
- o_reset_to_empty_unquoted(&ctx.as_string);
+#if ENABLE_HUSH_JOB
+ if (G.run_list_level == 1 && G_interactive_fd) {
+ /* Waits for completion, then fg's main shell */
+ rcode = checkjobs_and_fg_shell(pi);
+ debug_printf_exec(": checkjobs_and_fg_shell exitcode %d\n", rcode);
+ check_and_run_traps(0);
+ } else
#endif
+ { /* This one just waits for completion */
+ rcode = checkjobs(pi);
+ debug_printf_exec(": checkjobs exitcode %d\n", rcode);
+ check_and_run_traps(0);
+ }
+ G.last_exitcode = rcode;
}
- goto new_cmd;
- case '(':
-#if ENABLE_HUSH_CASE
- /* "case... in [(]word)..." - skip '(' */
- if (ctx.ctx_res_w == RES_MATCH
- && ctx.command->argv == NULL /* not (word|(... */
- && dest.length == 0 /* not word(... */
- && dest.o_quoted == 0 /* not ""(... */
- ) {
- continue;
- }
+ }
+
+ /* Analyze how result affects subsequent commands */
+#if ENABLE_HUSH_IF
+ if (rword == RES_IF || rword == RES_ELIF)
+ cond_code = rcode;
#endif
- case '{':
- if (parse_group(&dest, &ctx, input, ch) != 0) {
- goto parse_error;
+#if ENABLE_HUSH_LOOPS
+ /* Beware of "while false; true; do ..."! */
+ if (pi->next && pi->next->res_word == RES_DO) {
+ if (rword == RES_WHILE) {
+ if (rcode) {
+ /* "while false; do...done" - exitcode 0 */
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ debug_printf_exec(": while expr is false: breaking (exitcode:EXIT_SUCCESS)\n");
+ goto check_jobs_and_break;
+ }
+ }
+ if (rword == RES_UNTIL) {
+ if (!rcode) {
+ debug_printf_exec(": until expr is true: breaking\n");
+ check_jobs_and_break:
+ checkjobs(NULL);
+ break;
+ }
}
- goto new_cmd;
- case ')':
-#if ENABLE_HUSH_CASE
- if (ctx.ctx_res_w == RES_MATCH)
- goto case_semi;
-#endif
- case '}':
- /* proper use of this character is caught by end_trigger:
- * if we see {, we call parse_group(..., end_trigger='}')
- * and it will match } earlier (not here). */
- syntax_error_unexpected_ch(ch);
- goto parse_error;
- default:
- if (HUSH_DEBUG)
- bb_error_msg_and_die("BUG: unexpected %c\n", ch);
}
- } /* while (1) */
+#endif
- parse_error:
- {
- struct parse_context *pctx;
- IF_HAS_KEYWORDS(struct parse_context *p2;)
+ check_jobs_and_continue:
+ checkjobs(NULL);
+ } /* for (pi) */
- /* Clean up allocated tree.
- * Sample for finding leaks on syntax error recovery path.
- * Run it from interactive shell, watch pmap `pidof hush`.
- * while if false; then false; fi; do break; fi
- * Samples to catch leaks at execution:
- * while if (true | {true;}); then echo ok; fi; do break; done
- * while if (true | {true;}); then echo ok; fi; do (if echo ok; break; then :; fi) | cat; break; done
- */
- pctx = &ctx;
- do {
- /* Update pipe/command counts,
- * otherwise freeing may miss some */
- done_pipe(pctx, PIPE_SEQ);
- debug_printf_clean("freeing list %p from ctx %p\n",
- pctx->list_head, pctx);
- debug_print_tree(pctx->list_head, 0);
- free_pipe_list(pctx->list_head);
- debug_printf_clean("freed list %p\n", pctx->list_head);
-#if !BB_MMU
- o_free_unsafe(&pctx->as_string);
+#if ENABLE_HUSH_JOB
+ G.run_list_level--;
#endif
- IF_HAS_KEYWORDS(p2 = pctx->stack;)
- if (pctx != &ctx) {
- free(pctx);
- }
- IF_HAS_KEYWORDS(pctx = p2;)
- } while (HAS_KEYWORDS && pctx);
- /* Free text, clear all dest fields */
- o_free(&dest);
- /* If we are not in top-level parse, we return,
- * our caller will propagate error.
- */
- if (end_trigger != ';') {
-#if !BB_MMU
- if (pstring)
- *pstring = NULL;
+#if ENABLE_HUSH_LOOPS
+ if (loop_top)
+ G.depth_of_loop--;
+ free(for_list);
#endif
- debug_leave();
- return ERR_PTR;
- }
- /* Discard cached input, force prompt */
- input->p = NULL;
- IF_HUSH_INTERACTIVE(input->promptme = 1;)
- goto reset;
- }
+#if ENABLE_HUSH_CASE
+ free(case_word);
+#endif
+ debug_leave();
+ debug_printf_exec("run_list lvl %d return %d\n", G.run_list_level + 1, rcode);
+ return rcode;
}
-/* Executing from string: eval, sh -c '...'
- * or from file: /etc/profile, . file, sh <script>, sh (intereactive)
- * end_trigger controls how often we stop parsing
- * NUL: parse all, execute, return
- * ';': parse till ';' or newline, execute, repeat till EOF
- */
-static void parse_and_run_stream(struct in_str *inp, int end_trigger)
+/* Select which version we will use */
+static int run_and_free_list(struct pipe *pi)
{
- /* Why we need empty flag?
- * An obscure corner case "false; ``; echo $?":
- * empty command in `` should still set $? to 0.
- * But we can't just set $? to 0 at the start,
- * this breaks "false; echo `echo $?`" case.
- */
- bool empty = 1;
- while (1) {
- struct pipe *pipe_list;
-
- pipe_list = parse_stream(NULL, inp, end_trigger);
- if (!pipe_list) { /* EOF */
- if (empty)
- G.last_exitcode = 0;
- break;
- }
- debug_print_tree(pipe_list, 0);
- debug_printf_exec("parse_and_run_stream: run_and_free_list\n");
- run_and_free_list(pipe_list);
- empty = 0;
+ int rcode = 0;
+ debug_printf_exec("run_and_free_list entered\n");
+ if (!G.n_mode) {
+ debug_printf_exec(": run_list: 1st pipe with %d cmds\n", pi->num_cmds);
+ rcode = run_list(pi);
}
+ /* free_pipe_list has the side effect of clearing memory.
+ * In the long run that function can be merged with run_list,
+ * but doing that now would hobble the debugging effort. */
+ free_pipe_list(pi);
+ debug_printf_exec("run_and_free_list return %d\n", rcode);
+ return rcode;
}
-static void parse_and_run_string(const char *s)
-{
- struct in_str input;
- setup_string_in_str(&input, s);
- parse_and_run_stream(&input, '\0');
-}
-
-static void parse_and_run_file(FILE *f)
-{
- struct in_str input;
- setup_file_in_str(&input, f);
- parse_and_run_stream(&input, ';');
-}
/* Called a few times only (or even once if "sh -c") */
static void init_sigmasks(void)
{
int state = (cstate == '-' ? 1 : 0);
switch (mode) {
- case 'n': G.fake_mode = state; break;
- case 'x': G.x_mode = state; break;
+ case 'n': G.n_mode = state; break;
+ case 'x': IF_HUSH_MODE_X(G_x_mode = state;) break;
default: return EXIT_FAILURE;
}
return EXIT_SUCCESS;
int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int hush_main(int argc, char **argv)
{
- static const struct variable const_shell_ver = {
- .next = NULL,
- .varstr = (char*)hush_version_str,
- .max_len = 1, /* 0 can provoke free(name) */
- .flg_export = 1,
- .flg_read_only = 1,
- };
int opt;
unsigned builtin_argc;
char **e;
G.argv0_for_re_execing = argv[0];
#endif
/* Deal with HUSH_VERSION */
- G.shell_ver = const_shell_ver; /* copying struct here */
+ G.shell_ver.flg_export = 1;
+ G.shell_ver.flg_read_only = 1;
+ /* Code which handles ${var/P/R} needs writable values for all variables,
+ * therefore we xstrdup: */
+ G.shell_ver.varstr = xstrdup(hush_version_str),
G.top_var = &G.shell_ver;
+ /* Create shell local variables from the values
+ * currently living in the environment */
debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION");
unsetenv("HUSH_VERSION"); /* in case it exists in initial env */
- /* Initialize our shell local variables with the values
- * currently living in the environment */
cur_var = G.top_var;
e = environ;
if (e) while (*e) {
}
e++;
}
- /* reinstate HUSH_VERSION */
- debug_printf_env("putenv '%s'\n", hush_version_str);
- putenv((char *)hush_version_str);
+ /* (Re)insert HUSH_VERSION into env (AFTER we scanned the env!) */
+ debug_printf_env("putenv '%s'\n", G.shell_ver.varstr);
+ putenv(G.shell_ver.varstr);
/* Export PWD */
set_pwd_var(/*exp:*/ 1);
}
-#if ENABLE_LASH
-int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int lash_main(int argc, char **argv)
-{
- bb_error_msg("lash is deprecated, please use hush instead");
- return hush_main(argc, argv);
-}
-#endif
-
#if ENABLE_MSH
int msh_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int msh_main(int argc, char **argv)
{
do {
char *name = *argv;
+ char *name_end = strchrnul(name, '=');
/* So far we do not check that name is valid (TODO?) */
- if (strchr(name, '=') == NULL) {
- struct variable *var;
+ if (*name_end == '\0') {
+ struct variable *var, **vpp;
+
+ vpp = get_ptr_to_local_var(name, name_end - name);
+ var = vpp ? *vpp : NULL;
- var = get_local_var(name);
if (exp == -1) { /* unexporting? */
/* export -n NAME (without =VALUE) */
if (var) {
projects / oweals / busybox.git / blobdiff