* rewrites.
*
* Other credits:
- * o_addchr() derived from similar w_addchar function in glibc-2.2.
- * setup_redirect(), redirect_opt_num(), and big chunks of main()
+ * o_addchr derived from similar w_addchar function in glibc-2.2.
+ * setup_redirect, redirect_opt_num, and big chunks of main
* and many builtins derived from contributions by Erik Andersen.
* Miscellaneous bugfixes from Matt Kraai.
*
#define SPECIAL_VAR_SYMBOL 3
typedef enum redir_type {
+ REDIRECT_INVALID = 0,
REDIRECT_INPUT = 1,
REDIRECT_OVERWRITE = 2,
REDIRECT_APPEND = 3,
- REDIRECT_HEREIS = 4,
- REDIRECT_IO = 5
+ REDIRECT_HEREDOC = 4,
+ REDIRECT_IO = 5,
+ REDIRECT_HEREDOC2 = 6, /* REDIRECT_HEREDOC after heredoc load */
} redir_type;
/* The descrip member of this structure is only used to make
signed char default_fd;
char descrip[3];
} redir_table[] = {
- { 0, 0, "()" },
+ { 0, 0, "??" },
{ O_RDONLY, 0, "<" },
{ O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
{ O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
- { O_RDONLY, -1, "<<" },
- { O_RDWR, 1, "<>" }
+ { O_RDONLY, 0, "<<" },
+ { O_CREAT|O_RDWR, 1, "<>" },
+/* Should not be needed. Bogus default_fd helps in debugging */
+/* { O_RDONLY, 77, "<<" }, */
};
typedef enum reserved_style {
}
+//TODO: fix big string case!
+static void setup_heredoc(int fd, const char *heredoc)
+{
+ struct fd_pair pair;
+ pid_t pid;
+
+ xpiped_pair(pair);
+ pid = vfork();
+ if (pid < 0)
+ bb_perror_msg_and_die("vfork");
+ if (pid == 0) { /* child */
+ die_sleep = 0;
+ close(pair.rd);
+ xwrite_str(pair.wr, heredoc);
+ _exit(0);
+ }
+ /* parent */
+ die_sleep = -1;
+ close(pair.wr);
+ xmove_fd(pair.rd, fd);
+}
+
/* 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[])
{
+//TODO: no callers ever check return value - ?!
int openfd, mode;
struct redir_struct *redir;
for (redir = prog->redirects; redir; redir = redir->next) {
- if (redir->dup == -1 && redir->rd_filename == NULL) {
- /* something went wrong in the parse. Pretend it didn't happen */
+ if (redir->rd_type == REDIRECT_HEREDOC2) {
+ if (squirrel && redir->fd < 3) {
+ squirrel[redir->fd] = dup(redir->fd);
+ }
+ /* for REDIRECT_HEREDOC2, rd_filename holds _contents_
+ * of the heredoc */
+ debug_printf_parse("set heredoc '%s'\n",
+ redir->rd_filename);
+ setup_heredoc(redir->fd, redir->rd_filename);
continue;
}
+
if (redir->dup == -1) {
char *p;
+ if (redir->rd_filename == NULL) {
+ /* Something went wrong in the parse.
+ * Pretend it didn't happen */
+ continue;
+ }
mode = redir_table[redir->rd_type].mode;
//TODO: check redir for names like '\\'
p = expand_string_to_string(redir->rd_filename);
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!) */
+ * bash and ash both lose it as well (though zsh doesn't!) */
+//what the above comment tries to say?
return 1;
}
} else {
}
-/* Peek ahead in the in_str to find out if we have a "&n" construct,
- * as in "2>&1", that represents duplicating a file descriptor.
- * Return either -2 (syntax error), -1 (no &), or the number found.
- */
-static int redirect_dup_num(struct in_str *input)
-{
- int ch, d = 0, ok = 0;
- ch = i_peek(input);
- if (ch != '&') return -1;
-
- i_getch(input); /* get the & */
- ch = i_peek(input);
- if (ch == '-') {
- i_getch(input);
- return -3; /* "-" represents "close me" */
- }
- while (isdigit(ch)) {
- d = d*10 + (ch-'0');
- ok = 1;
- i_getch(input);
- ch = i_peek(input);
- }
- if (ok) return d;
-
- bb_error_msg("ambiguous redirect");
- return -2;
-}
-
-/* The src parameter allows us to peek forward to a possible &n syntax
- * for file descriptor duplication, e.g., "2>&1".
- * Return code is 0 normally, 1 if a syntax error is detected in src.
- * Resource errors (in xmalloc) cause the process to exit */
-static int setup_redirect(struct parse_context *ctx,
- int fd,
- redir_type style,
- struct in_str *input)
-{
- struct command *command = ctx->command;
- struct redir_struct *redir;
- struct redir_struct **redirp;
- int dup_num;
-
- /* Check for a '2>&1' type redirect */
- dup_num = redirect_dup_num(input);
- if (dup_num == -2)
- return 1; /* syntax error */
-
- /* Create a new redir_struct and drop it onto the end of 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->fd = (fd == -1) ? redir_table[style].default_fd : fd;
-
- debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
-
- redir->dup = dup_num;
- if (dup_num != -1) {
- /* 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("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
- } else {
- /* We do _not_ try to open the file that src points to,
- * since we need to return and let src be expanded first.
- * Set ctx->pending_redirect, so we know what to do at the
- * end of the next parsed word. */
- ctx->pending_redirect = redir;
- }
- return 0;
-}
-
-
static struct pipe *new_pipe(void)
{
struct pipe *pi;
done_command(ctx);
}
-
/* If a reserved word is found and processed, parse context is modified
* and 1 is returned.
*/
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);
word->o_assignment = NOT_ASSIGNMENT;
- debug_printf("word stored in rd_filename: '%s'\n", word->data);
+ debug_printf_parse("word stored in rd_filename: '%s'\n", word->data);
} else {
/* "{ echo foo; } echo bar" - bad */
/* NB: bash allows e.g.:
* if true; then { echo foo; } fi
* while if false; then false; fi do break; done
+ * and disallows:
+ * while if false; then false; fi; do; break; done
* TODO? */
if (command->group) {
syntax(word->data);
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: -3 if >&- "close fd" construct is seen,
+ * -2 (syntax error), -1 if no & was seen, or the number found.
+ */
+#if BB_MMU
+#define redirect_dup_num(as_string, input) \
+ redirect_dup_num(input)
+#endif
+static int redirect_dup_num(o_string *as_string, struct in_str *input)
+{
+ int ch, d, ok;
+
+ ch = i_peek(input);
+ if (ch != '&')
+ return -1;
+
+ ch = i_getch(input); /* get the & */
+#if !BB_MMU
+ o_addchr(as_string, ch);
+#endif
+ ch = i_peek(input);
+ if (ch == '-') {
+ ch = i_getch(input);
+#if !BB_MMU
+ o_addchr(as_string, ch);
+#endif
+ return -3; /* "-" represents "close me" */
+ }
+ d = 0;
+ ok = 0;
+ while (ch != EOF && isdigit(ch)) {
+ d = d*10 + (ch-'0');
+ ok = 1;
+ ch = i_getch(input);
+#if !BB_MMU
+ o_addchr(as_string, ch);
+#endif
+ ch = i_peek(input);
+ }
+ 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 -2;
+}
+
+/* Return code is 0 normally, 1 if a syntax error is detected
+ */
+static int parse_redirect(struct parse_context *ctx,
+ int fd,
+ redir_type style,
+ struct in_str *input)
+{
+ struct command *command = ctx->command;
+ struct redir_struct *redir;
+ struct redir_struct **redirp;
+ int dup_num;
+
+ dup_num = -1;
+ if (style != REDIRECT_HEREDOC) {
+ /* Check for a '2>&1' type redirect */
+ dup_num = redirect_dup_num(&ctx->as_string, input);
+ if (dup_num == -2)
+ return 1; /* syntax error */
+ }
+//TODO: else { check for <<-word }
+
+ if (style == REDIRECT_OVERWRITE && dup_num == -1) {
+ 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);
+#if !BB_MMU
+ o_addchr(&ctx->as_string, ch);
+#endif
+ }
+ }
+
+ /* 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->fd = (fd == -1) ? redir_table[style].default_fd : fd;
+
+ debug_printf_parse("redirect type %d %s\n", redir->fd, redir_table[style].descrip);
+
+ redir->dup = dup_num;
+ if (dup_num != -1) {
+ /* 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->fd, redir->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
* 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
- * A -1 output from this program means no valid number was found, so the
- * caller should use the appropriate default for this redirection.
+ *
+ * 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"
+ * I am not sure we do it right (and not sure we care)
+ *
+ * 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;
- if (o->length == 0)
+ if (o->data == NULL)
+ return -1;
+ num = bb_strtou(o->data, NULL, 10);
+ if (errno || num < 0)
return -1;
- for (num = 0; num < o->length; num++) {
- if (!isdigit(o->data[num])) {
- return -1;
- }
- }
- num = atoi(o->data);
o_reset(o);
return num;
}
+//TODO: add NOMMU as_string fill
+static char *fetch_till_str(struct in_str *input, const char *word)
+{
+ o_string heredoc = NULL_O_STRING;
+ int past_EOL = 0;
+ int ch;
+
+ while (1) {
+ ch = i_getch(input);
+ if (ch == EOF) {
+ o_free_unsafe(&heredoc);
+ return NULL;
+ }
+ 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;
+ }
+ past_EOL = heredoc.length + 1;
+ }
+ o_addchr(&heredoc, ch);
+ }
+}
+
+static int fetch_heredocs(int heredoc_cnt, struct parse_context *ctx, struct in_str *input)
+{
+ struct pipe *pi = ctx->list_head;
+
+ while (pi) {
+ 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 *redirect = cmd->redirects;
+
+ debug_printf_parse("fetch_heredocs: %d cmd argv0:'%s'\n",
+ i, cmd->argv ? cmd->argv[0] : "NONE");
+ while (redirect) {
+ if (redirect->rd_type == REDIRECT_HEREDOC) {
+ char *p;
+
+ if (heredoc_cnt <= 0)
+ return 1; /* error */
+ redirect->rd_type = REDIRECT_HEREDOC2;
+ p = fetch_till_str(input, redirect->rd_filename);
+ if (!p)
+ return 1; /* unexpected EOF */
+ free(redirect->rd_filename);
+ redirect->rd_filename = p;
+ heredoc_cnt--;
+ }
+ redirect = redirect->next;
+ }
+ cmd++;
+ }
+ pi = pi->next;
+ }
+ /* Should be 0. If it isn't, it's a parse error */
+ return heredoc_cnt;
+}
+
+
#if BB_MMU
#define parse_stream(pstring, input, end_trigger) \
parse_stream(input, end_trigger)
again:
ch = i_getch(input);
#if !BB_MMU
- if (as_string && ch != EOF)
- o_addchr(as_string, ch);
+ if (as_string && ch != EOF) o_addchr(as_string, ch);
#endif
if (ch == dquote_end) { /* may be only '"' or EOF */
dest->nonnull = 1;
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
/* 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;
ch, ch, dest.o_escape);
if (ch == EOF) {
struct pipe *pi;
+
+ if (heredoc_cnt) {
+ syntax("unterminated here document");
+ goto parse_error;
+ }
if (done_word(&dest, &ctx)) {
goto parse_error;
}
#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 */
}
}
- if (end_trigger && end_trigger == ch) {
+ if (end_trigger && end_trigger == ch
+ && (heredoc_cnt == 0 || end_trigger != ';')
+ ) {
//TODO: disallow "{ cmd }" without semicolon
+ if (heredoc_cnt) {
+ /* This is technically valid:
+ * { cat <<HERE; }; echo Ok
+ * heredoc
+ * heredoc
+ * heredoc
+ * HERE
+ * but we don't support this.
+ * We require heredoc to be in enclosing {}/(),
+ * if any.
+ */
+ syntax("unterminated here document");
+ goto parse_error;
+ }
if (done_word(&dest, &ctx)) {
goto parse_error;
}
goto parse_error;
}
#endif
- setup_redirect(&ctx, redir_fd, redir_style, input);
+ if (parse_redirect(&ctx, redir_fd, redir_style, input))
+ goto parse_error;
break;
case '<':
redir_fd = redirect_opt_num(&dest);
}
redir_style = REDIRECT_INPUT;
if (next == '<') {
- redir_style = REDIRECT_HEREIS;
+ redir_style = REDIRECT_HEREDOC;
+ heredoc_cnt++;
+ debug_printf_parse("++heredoc_cnt=%d\n", heredoc_cnt);
ch = i_getch(input);
#if !BB_MMU
o_addchr(&ctx.as_string, ch);
goto parse_error;
}
#endif
- setup_redirect(&ctx, redir_fd, redir_style, input);
+ if (parse_redirect(&ctx, redir_fd, redir_style, input))
+ goto parse_error;
break;
case ';':
#if ENABLE_HUSH_CASE
projects / oweals / busybox.git / commitdiff