* Brace Expansion
* Tilde Expansion
* fancy forms of Parameter Expansion
+ * aliases
* Arithmetic Expansion
* <(list) and >(list) Process Substitution
- * reserved words: case, esac, function
+ * reserved words: case, esac, select, function
* Here Documents ( << word )
* Functions
* Major bugs:
* job handling woefully incomplete and buggy
* reserved word execution woefully incomplete and buggy
* to-do:
- * port selected bugfixes from post-0.49 busybox lash
- * finish implementing reserved words
+ * port selected bugfixes from post-0.49 busybox lash - done?
+ * finish implementing reserved words: for, while, until, do, done
+ * change { and } from special chars to reserved words
+ * builtins: break, continue, eval, return, set, trap, ulimit
+ * test magic exec
* handle children going into background
* clean up recognition of null pipes
- * have builtin_exec set flag to avoid restore_redirects
- * figure out if "echo foo}" is fixable
* check setting of global_argc and global_argv
* control-C handling, probably with longjmp
- * VAR=value prefix for simple commands
* follow IFS rules more precisely, including update semantics
- * write builtin_eval, builtin_ulimit, builtin_umask
* figure out what to do with backslash-newline
* explain why we use signal instead of sigaction
* propagate syntax errors, die on resource errors?
* continuation lines, both explicit and implicit - done?
* memory leak finding and plugging - done?
* more testing, especially quoting rules and redirection
+ * document how quoting rules not precisely followed for variable assignments
* maybe change map[] to use 2-bit entries
* (eventually) remove all the printf's
*
#include <fcntl.h>
#include <getopt.h> /* should be pretty obvious */
+#include <sys/stat.h> /* ulimit */
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#define applet_name "hush"
#include "standalone.h"
#define shell_main main
-#define BB_FEATURE_SH_SIMPLE_PROMPT
+#undef BB_FEATURE_SH_FANCY_PROMPT
#endif
typedef enum {
struct close_me *next;
};
+struct variables {
+ char *name;
+ char *value;
+ int flg_export;
+ int flg_read_only;
+ struct variables *next;
+};
+
/* globals, connect us to the outside world
* the first three support $?, $#, and $1 */
char **global_argv;
* context when someone hits ^C */
/* "globals" within this file */
-static char *ifs=NULL;
+static char *ifs;
static char map[256];
-static int fake_mode=0;
-static int interactive=0;
-static struct close_me *close_me_head = NULL;
-static char *cwd;
+static int fake_mode;
+static int interactive;
+static struct close_me *close_me_head;
+static const char *cwd;
static struct jobset *job_list;
-static unsigned int last_bg_pid=0;
+static unsigned int last_bg_pid;
static char *PS1;
-static char *PS2 = "> ";
+static char *PS2;
+struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
+struct variables *top_vars = &shell_ver;
#define B_CHUNK (100)
#define B_NOSPAC 1
-#define MAX_LINE 256 /* for cwd */
-#define MAX_READ 256 /* for builtin_read */
typedef struct {
char *data;
va_end(args);
}
#else
-static void debug_printf(const char *format, ...) { }
+static inline void debug_printf(const char *format, ...) { }
#endif
#define final_printf debug_printf
-void __syntax(char *file, int line) {
- fprintf(stderr,"syntax error %s:%d\n",file,line);
+static void __syntax(char *file, int line) {
+ error_msg("syntax error %s:%d", file, line);
}
#define syntax() __syntax(__FILE__, __LINE__)
static int builtin_jobs(struct child_prog *child);
static int builtin_pwd(struct child_prog *child);
static int builtin_read(struct child_prog *child);
+static int builtin_set(struct child_prog *child);
static int builtin_shift(struct child_prog *child);
static int builtin_source(struct child_prog *child);
-static int builtin_ulimit(struct child_prog *child);
static int builtin_umask(struct child_prog *child);
static int builtin_unset(struct child_prog *child);
+static int builtin_not_written(struct child_prog *child);
/* o_string manipulation: */
static int b_check_space(o_string *o, int len);
static int b_addchr(o_string *o, int ch);
static int pipe_wait(struct pipe *pi);
static int run_list_real(struct pipe *pi);
static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
+int controlling_tty(int check_pgrp);
static int run_pipe_real(struct pipe *pi);
/* extended glob support: */
static int globhack(const char *src, int flags, glob_t *pglob);
static int glob_needed(const char *s);
static int xglob(o_string *dest, int flags, glob_t *pglob);
+/* variable assignment: */
+static int is_assignment(const char *s);
/* data structure manipulation: */
static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
static void initialize_context(struct p_context *ctx);
static void insert_bg_job(struct pipe *pi);
static void remove_bg_job(struct pipe *pi);
static void free_pipe(struct pipe *pi);
+/* local variable support */
+static char *get_local_var(const char *var);
+static void unset_local_var(const char *name);
+static int set_local_var(const char *s, int flg_export);
+
/* Table of built-in functions. They can be forked or not, depending on
* context: within pipes, they fork. As simple commands, they do not.
* still be set at the end. */
static struct built_in_command bltins[] = {
{"bg", "Resume a job in the background", builtin_fg_bg},
+ {"break", "Exit for, while or until loop", builtin_not_written},
{"cd", "Change working directory", builtin_cd},
+ {"continue", "Continue for, while or until loop", builtin_not_written},
{"env", "Print all environment variables", builtin_env},
- {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec},
+ {"eval", "Construct and run shell command", builtin_not_written},
+ {"exec", "Exec command, replacing this shell with the exec'd process",
+ builtin_exec},
{"exit", "Exit from shell()", builtin_exit},
{"export", "Set environment variable", builtin_export},
{"fg", "Bring job into the foreground", builtin_fg_bg},
{"jobs", "Lists the active jobs", builtin_jobs},
{"pwd", "Print current directory", builtin_pwd},
{"read", "Input environment variable", builtin_read},
+ {"return", "Return from a function", builtin_not_written},
+ {"set", "Set/unset shell local variables", builtin_set},
{"shift", "Shift positional parameters", builtin_shift},
- {"ulimit","Controls resource limits", builtin_ulimit},
+ {"trap", "Trap signals", builtin_not_written},
+ {"ulimit","Controls resource limits", builtin_not_written},
{"umask","Sets file creation mask", builtin_umask},
{"unset", "Unset environment variable", builtin_unset},
{".", "Source-in and run commands in a file", builtin_source},
{NULL, NULL, NULL}
};
+static const char *set_cwd(void)
+{
+ if(cwd==unknown)
+ cwd = NULL; /* xgetcwd(arg) called free(arg) */
+ cwd = xgetcwd((char *)cwd);
+ if (!cwd)
+ cwd = unknown;
+ return cwd;
+}
+
+
/* built-in 'cd <path>' handler */
static int builtin_cd(struct child_prog *child)
{
printf("cd: %s: %s\n", newdir, strerror(errno));
return EXIT_FAILURE;
}
- getcwd(cwd, sizeof(char)*MAX_LINE);
+ set_cwd();
return EXIT_SUCCESS;
}
/* built-in 'export VAR=value' handler */
static int builtin_export(struct child_prog *child)
{
- int res;
+ int res = 0;
+ char *name = child->argv[1];
- if (child->argv[1] == NULL) {
+ if (name == NULL) {
return (builtin_env(child));
}
- res = putenv(child->argv[1]);
- if (res)
- fprintf(stderr, "export: %s\n", strerror(errno));
- return (res);
+
+ name = strdup(name);
+
+ if(name) {
+ char *value = strchr(name, '=');
+
+ if (!value) {
+ char *tmp;
+ /* They are exporting something without an =VALUE */
+
+ value = get_local_var(name);
+ if (value) {
+ size_t ln = strlen(name);
+
+ tmp = realloc(name, ln+strlen(value)+2);
+ if(tmp==NULL)
+ res = -1;
+ else {
+ sprintf(tmp+ln, "=%s", value);
+ name = tmp;
+ }
+ } else {
+ /* bash does not return an error when trying to export
+ * an undefined variable. Do likewise. */
+ res = 1;
+ }
+ }
+ }
+ if (res<0)
+ perror_msg("export");
+ else if(res==0)
+ res = set_local_var(name, 1);
+ else
+ res = 0;
+ free(name);
+ return res;
}
/* built-in 'fg' and 'bg' handler */
signal(SIGTTOU, SIG_IGN);
/* suppress messages when run from /linuxrc mag@sysgo.de */
if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-1");
signal(SIGTTOU, SIG_DFL);
job_list->fg = pi;
}
/* built-in 'pwd' handler */
static int builtin_pwd(struct child_prog *dummy)
{
- getcwd(cwd, MAX_LINE);
- puts(cwd);
+ puts(set_cwd());
return EXIT_SUCCESS;
}
/* built-in 'read VAR' handler */
static int builtin_read(struct child_prog *child)
{
- int res = 0, len, newlen;
- char *s;
- char string[MAX_READ];
+ int res;
if (child->argv[1]) {
- /* argument (VAR) given: put "VAR=" into buffer */
- strcpy(string, child->argv[1]);
- len = strlen(string);
- string[len++] = '=';
- string[len] = '\0';
- /* XXX would it be better to go through in_str? */
- fgets(&string[len], sizeof(string) - len, stdin); /* read string */
- newlen = strlen(string);
- if(newlen > len)
- string[--newlen] = '\0'; /* chomp trailing newline */
- /*
- ** string should now contain "VAR=<value>"
- ** copy it (putenv() won't do that, so we must make sure
- ** the string resides in a static buffer!)
- */
- res = -1;
- if((s = strdup(string)))
- res = putenv(s);
+ char string[BUFSIZ];
+ char *var = 0;
+
+ string[0] = 0; /* In case stdin has only EOF */
+ /* read string */
+ fgets(string, sizeof(string), stdin);
+ chomp(string);
+ var = malloc(strlen(child->argv[1])+strlen(string)+2);
+ if(var) {
+ sprintf(var, "%s=%s", child->argv[1], string);
+ res = set_local_var(var, 0);
+ } else
+ res = -1;
if (res)
- fprintf(stderr, "read: %s\n", strerror(errno));
+ fprintf(stderr, "read: %m\n");
+ free(var); /* So not move up to avoid breaking errno */
+ return res;
+ } else {
+ do res=getchar(); while(res!='\n' && res!=EOF);
+ return 0;
}
+}
+
+/* built-in 'set VAR=value' handler */
+static int builtin_set(struct child_prog *child)
+{
+ char *temp = child->argv[1];
+ struct variables *e;
+
+ if (temp == NULL)
+ for(e = top_vars; e; e=e->next)
+ printf("%s=%s\n", e->name, e->value);
else
- fgets(string, sizeof(string), stdin);
+ set_local_var(temp, 0);
- return (res);
+ return EXIT_SUCCESS;
}
+
/* Built-in 'shift' handler */
static int builtin_shift(struct child_prog *child)
{
/* XXX search through $PATH is missing */
input = fopen(child->argv[1], "r");
if (!input) {
- fprintf(stderr, "Couldn't open file '%s'\n", child->argv[1]);
+ error_msg("Couldn't open file '%s'", child->argv[1]);
return EXIT_FAILURE;
}
return (status);
}
-static int builtin_ulimit(struct child_prog *child)
-{
- printf("builtin_ulimit not written\n");
- return EXIT_FAILURE;
-}
-
static int builtin_umask(struct child_prog *child)
{
- printf("builtin_umask not written\n");
- return EXIT_FAILURE;
+ mode_t new_umask;
+ const char *arg = child->argv[1];
+ char *end;
+ if (arg) {
+ new_umask=strtoul(arg, &end, 8);
+ if (*end!='\0' || end == arg) {
+ return EXIT_FAILURE;
+ }
+ } else {
+ printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
+ }
+ umask(new_umask);
+ return EXIT_SUCCESS;
}
/* built-in 'unset VAR' handler */
static int builtin_unset(struct child_prog *child)
{
- if (child->argv[1] == NULL) {
- fprintf(stderr, "unset: parameter required.\n");
- return EXIT_FAILURE;
- }
- unsetenv(child->argv[1]);
+ /* bash returned already true */
+ unset_local_var(child->argv[1]);
return EXIT_SUCCESS;
}
+static int builtin_not_written(struct child_prog *child)
+{
+ printf("builtin_%s not written\n",child->argv[0]);
+ return EXIT_FAILURE;
+}
+
static int b_check_space(o_string *o, int len)
{
/* It would be easy to drop a more restrictive policy
static inline void cmdedit_set_initial_prompt(void)
{
-#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
+#ifndef BB_FEATURE_SH_FANCY_PROMPT
PS1 = NULL;
#else
PS1 = getenv("PS1");
static inline void setup_prompt_string(int promptmode, char **prompt_str)
{
debug_printf("setup_prompt_string %d ",promptmode);
-#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
+#ifndef BB_FEATURE_SH_FANCY_PROMPT
/* Set up the prompt */
if (promptmode == 1) {
if (PS1)
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!) */
- fprintf(stderr,"error opening %s: %s\n", redir->word.gl_pathv[0],
- strerror(errno));
+ perror_msg("error opening %s", redir->word.gl_pathv[0]);
return 1;
}
} else {
if (squirrel && redir->fd < 3) {
squirrel[redir->fd] = dup(redir->fd);
}
- dup2(openfd, redir->fd);
- close(openfd);
+ if (openfd == -3) {
+ close(openfd);
+ } else {
+ dup2(openfd, redir->fd);
+ close(openfd);
+ }
}
}
return 0;
return rcode;
}
-/* very simple version for testing */
+/* never returns */
+/* XXX no 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? */
static void pseudo_exec(struct child_prog *child)
{
- int rcode;
+ int i, rcode;
struct built_in_command *x;
if (child->argv) {
+ for (i=0; is_assignment(child->argv[i]); i++) {
+ debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
+ putenv(strdup(child->argv[i]));
+ }
+ child->argv+=i; /* XXX this hack isn't so horrible, since we are about
+ to exit, and therefore don't need to keep data
+ structures consistent for free() use. */
+ /* If a variable is assigned in a forest, and nobody listens,
+ * was it ever really set?
+ */
+ if (child->argv[0] == NULL) {
+ _exit(EXIT_SUCCESS);
+ }
+
/*
* Check if the command matches any of the builtins.
* Depending on context, this might be redundant. But it's
for (x = bltins; x->cmd; x++) {
if (strcmp(child->argv[0], x->cmd) == 0 ) {
debug_printf("builtin exec %s\n", child->argv[0]);
- exit(x->function(child));
+ _exit(x->function(child));
}
}
#endif
debug_printf("exec of %s\n",child->argv[0]);
execvp(child->argv[0],child->argv);
- perror("execvp");
- exit(1);
+ perror_msg("couldn't exec: %s",child->argv[0]);
+ _exit(1);
} else if (child->group) {
debug_printf("runtime nesting to group\n");
interactive=0; /* crucial!!!! */
rcode = run_list_real(child->group);
/* OK to leak memory by not calling run_list_test,
* since this process is about to exit */
- exit(rcode);
+ _exit(rcode);
} else {
/* Can happen. See what bash does with ">foo" by itself. */
debug_printf("trying to pseudo_exec null command\n");
- exit(EXIT_SUCCESS);
+ _exit(EXIT_SUCCESS);
}
}
thejob->next = NULL;
thejob->running_progs = thejob->num_progs;
thejob->stopped_progs = 0;
+ thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
+
+ //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0])
+ {
+ char *bar=thejob->text;
+ char **foo=pi->progs[0].argv;
+ while(foo && *foo) {
+ bar += sprintf(bar, "%s ", *foo++);
+ }
+ }
/* we don't wait for background thejobs to return -- append it
to the list of backgrounded thejobs and leave it alone */
- printf("[%d] %d\n", pi->jobid, pi->pgrp);
- last_bg_pid = pi->pgrp;
+ printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
+ last_bg_pid = thejob->progs[0].pid;
}
/* remove a backgrounded job from a jobset */
{
struct pipe *prev_pipe;
- free_pipe(pi);
if (pi == job_list->head) {
job_list->head = pi->next;
} else {
prev_pipe->next = pi->next;
}
+ free_pipe(pi);
free(pi);
}
have, figure out why and see if a job has completed */
static void checkjobs()
{
- int status;
+ int status, ctty;
int prognum = 0;
struct pipe *pi;
pid_t childpid;
remove_bg_job(pi);
}
} else {
+ if(pi==NULL)
+ break;
/* child stopped */
pi->stopped_progs++;
pi->progs[prognum].is_stopped = 1;
if (pi->stopped_progs == pi->num_progs) {
- printf(JOB_STATUS_FORMAT, pi->jobid, "Stopped",
- pi->text);
+ printf(JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
}
}
}
perror_msg("waitpid");
/* move the shell to the foreground */
- if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ if (interactive && (ctty=controlling_tty(0))!=-1) {
+ if (tcsetpgrp(ctty, getpgrp()))
+ perror_msg("tcsetpgrp-2");
+ }
+}
+
+/* Figure out our controlling tty, checking in order stderr,
+ * stdin, and stdout. If check_pgrp is set, also check that
+ * we belong to the foreground process group associated with
+ * that tty. The value of ctty is needed in order to call
+ * tcsetpgrp(ctty, ...); */
+int controlling_tty(int check_pgrp)
+{
+ pid_t curpgrp;
+ int ctty;
+
+ if ((curpgrp = tcgetpgrp(ctty = 2)) < 0
+ && (curpgrp = tcgetpgrp(ctty = 0)) < 0
+ && (curpgrp = tcgetpgrp(ctty = 1)) < 0)
+ return errno = ENOTTY, -1;
+
+ if (check_pgrp && curpgrp != getpgrp())
+ return errno = EPERM, -1;
+
+ return ctty;
}
/* run_pipe_real() starts all the jobs, but doesn't wait for anything
ctty = -1;
nextin = 0;
- pi->pgrp = 0;
+ pi->pgrp = -1;
/* Check if we are supposed to run in the foreground */
- if (pi->followup!=PIPE_BG) {
- if ((pi->pgrp = tcgetpgrp(ctty = 2)) < 0
- && (pi->pgrp = tcgetpgrp(ctty = 0)) < 0
- && (pi->pgrp = tcgetpgrp(ctty = 1)) < 0)
- return errno = ENOTTY, -1;
-
- if (pi->pgrp < 0 && pi->pgrp != getpgrp())
- return errno = EPERM, -1;
+ if (interactive && pi->followup!=PIPE_BG) {
+ if ((ctty = controlling_tty(pi->pgrp<0)) < 0) return -1;
}
/* Check if this is a simple builtin (not part of a pipe).
restore_redirects(squirrel);
return rcode;
}
+ for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
+ if (i!=0 && child->argv[i]==NULL) {
+ /* assignments, but no command: set the local environment */
+ for (i=0; child->argv[i]!=NULL; i++) {
+ set_local_var(child->argv[i], 0);
+ }
+ return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
+ }
for (x = bltins; x->cmd; x++) {
- if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ if (strcmp(child->argv[i], x->cmd) == 0 ) {
int squirrel[] = {-1, -1, -1};
int rcode;
+ if (x->function == builtin_exec && child->argv[i+1]==NULL) {
+ debug_printf("magic exec\n");
+ setup_redirects(child,NULL);
+ return EXIT_SUCCESS;
+ }
debug_printf("builtin inline %s\n", child->argv[0]);
/* XXX 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 with glibc. */
setup_redirects(child, squirrel);
+ for (i=0; is_assignment(child->argv[i]); i++) {
+ putenv(strdup(child->argv[i]));
+ }
+ child->argv+=i; /* XXX horrible hack */
rcode = x->function(child);
+ child->argv-=i; /* XXX restore hack so free() can work right */
restore_redirects(squirrel);
return rcode;
}
* and the pipe fd is available for dup'ing. */
setup_redirects(child,NULL);
- if (pi->followup!=PIPE_BG) {
- /* Put our child in the process group whose leader is the
- * first process in this pipe. */
+ if (interactive && pi->followup!=PIPE_BG) {
+ /* If we (the child) win the race, put ourselves in the process
+ * group whose leader is the first process in this pipe. */
if (pi->pgrp < 0) {
- pi->pgrp = child->pid;
+ pi->pgrp = getpid();
}
- /* Don't check for errors. The child may be dead already,
- * in which case setpgid returns error code EACCES. */
if (setpgid(0, pi->pgrp) == 0) {
signal(SIGTTOU, SIG_IGN);
tcsetpgrp(ctty, pi->pgrp);
if (interactive) {
/* move the new process group into the foreground */
/* suppress messages when run from /linuxrc mag@sysgo.de */
- //signal(SIGTTIN, SIG_IGN);
- //signal(SIGTTOU, SIG_IGN);
+ /* XXX probably this "0" should come from controlling_tty() */
if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
+ perror_msg("tcsetpgrp-3");
rcode = pipe_wait(pi);
if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
- //signal(SIGTTIN, SIG_DFL);
- //signal(SIGTTOU, SIG_DFL);
+ perror_msg("tcsetpgrp-4");
} else {
rcode = pipe_wait(pi);
+ debug_printf("pipe_wait returned %d\n",rcode);
}
}
last_return_code=rcode;
if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
(rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
skip_more_in_this_rmode=rmode;
- /* return rcode; */ /* XXX broken if list is part of if/then/else */
}
checkjobs();
return rcode;
gr = globhack(dest->data, flags, pglob);
debug_printf("globhack returned %d\n",gr);
}
- if (gr == GLOB_NOSPACE) {
- fprintf(stderr,"out of memory during glob\n");
- exit(1);
- }
+ if (gr == GLOB_NOSPACE)
+ error_msg_and_die("out of memory during glob");
if (gr != 0) { /* GLOB_ABORTED ? */
- fprintf(stderr,"glob(3) error %d\n",gr);
+ error_msg("glob(3) error %d",gr);
}
/* globprint(glob_target); */
return gr;
}
+/* This is used to get/check local shell variables */
+static char *get_local_var(const char *s)
+{
+ struct variables *cur;
+
+ if (!s)
+ return NULL;
+ for (cur = top_vars; cur; cur=cur->next)
+ if(strcmp(cur->name, s)==0)
+ return cur->value;
+ return NULL;
+}
+
+/* This is used to set local shell variables
+ flg_export==0 if only local (not exporting) variable
+ flg_export==1 if "new" exporting environ
+ flg_export>1 if current startup environ (not call putenv()) */
+static int set_local_var(const char *s, int flg_export)
+{
+ char *name, *value;
+ int result=0;
+ struct variables *cur;
+ char *newval = 0;
+
+ name=strdup(s);
+
+ /* Assume when we enter this function that we are already in
+ * NAME=VALUE format. So the first order of business is to
+ * split 's' on the '=' into 'name' and 'value' */
+ value = strchr(name, '=');
+ if (value==0 || (newval = strdup(value+1))==0) {
+ result = -1;
+ } else {
+ *value++ = 0;
+
+ for(cur = top_vars; cur; cur = cur->next) {
+ if(strcmp(cur->name, name)==0)
+ break;
+ }
+
+ if(cur) {
+ if(strcmp(cur->value, value)==0) {
+ if(flg_export>0 && cur->flg_export==0)
+ cur->flg_export=flg_export;
+ else
+ result++;
+ } else {
+ if(cur->flg_read_only) {
+ result = -1;
+ error_msg("%s: readonly variable", name);
+ } else {
+ if(flg_export>0 || cur->flg_export>1)
+ cur->flg_export=1;
+ free(cur->value);
+ cur->value = newval;
+ newval = 0; /* protect free */
+ }
+ }
+ } else {
+ cur = malloc(sizeof(struct variables));
+ if(cur==0) {
+ result = -1;
+ } else {
+ cur->name = strdup(name);
+ if(cur->name == 0) {
+ free(cur);
+ result = -1;
+ } else {
+ struct variables *bottom = top_vars;
+ cur->value = newval;
+ newval = 0; /* protect free */
+ cur->next = 0;
+ cur->flg_export = flg_export;
+ cur->flg_read_only = 0;
+ while(bottom->next) bottom=bottom->next;
+ bottom->next = cur;
+ }
+ }
+ }
+ }
+
+ if(result==0 && cur->flg_export==1) {
+ *(value-1) = '=';
+ result = putenv(name);
+ } else {
+ free(name);
+ if(result>0) /* equivalent to previous set */
+ result = 0;
+ }
+ free(newval);
+ return result;
+}
+
+static void unset_local_var(const char *name)
+{
+ struct variables *cur;
+
+ if (name) {
+ for (cur = top_vars; cur; cur=cur->next) {
+ if(strcmp(cur->name, name)==0)
+ break;
+ }
+ if(cur!=0) {
+ struct variables *next = top_vars;
+ if(cur->flg_read_only) {
+ error_msg("%s: readonly variable", name);
+ return;
+ } else {
+ if(cur->flg_export)
+ unsetenv(cur->name);
+ free(cur->name);
+ free(cur->value);
+ while (next->next != cur)
+ next = next->next;
+ next->next = cur->next;
+ }
+ free(cur);
+ }
+ }
+}
+
+static int is_assignment(const char *s)
+{
+ if (s==NULL || !isalpha(*s)) return 0;
+ ++s;
+ while(isalnum(*s) || *s=='_') ++s;
+ return *s=='=';
+}
+
/* 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.
if (redir->dup == -2) return 1; /* syntax error */
if (redir->dup != -1) {
/* Erik had a check here that the file descriptor in question
- * is legit; I postpone that to "run time" */
+ * 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,
old->child->group = ctx->list_head;
*ctx = *old; /* physical copy */
free(old);
- ctx->w=RES_NONE;
}
b_reset (dest);
return 1;
if (ctx->pending_redirect) {
ctx->pending_redirect=NULL;
if (glob_target->gl_pathc != 1) {
- fprintf(stderr, "ambiguous redirect\n");
+ error_msg("ambiguous redirect");
return 1;
}
} else {
if (ch != '&') return -1;
b_getch(input); /* get the & */
- while (ch=b_peek(input),isdigit(ch)) {
+ ch=b_peek(input);
+ if (ch == '-') {
+ b_getch(input);
+ return -3; /* "-" represents "close me" */
+ }
+ while (isdigit(ch)) {
d = d*10+(ch-'0');
ok=1;
b_getch(input);
+ ch = b_peek(input);
}
if (ok) return d;
- fprintf(stderr, "ambiguous redirect\n");
+ error_msg("ambiguous redirect");
return -2;
}
#if 0
#define SURROGATE "surrogate response"
write(1,SURROGATE,sizeof(SURROGATE));
- exit(run_list(head));
+ _exit(run_list(head));
#else
- exit(run_list_real(head)); /* leaks memory */
+ _exit(run_list_real(head)); /* leaks memory */
#endif
}
debug_printf("forked child %d\n",pid);
static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src)
{
const char *p=NULL;
- if (src->data) p = getenv(src->data);
+ if (src->data) {
+ p = getenv(src->data);
+ if (!p)
+ p = get_local_var(src->data);
+ }
if (p) parse_string(dest, ctx, p); /* recursion */
b_free(src);
}
case '-':
case '_':
/* still unhandled, but should be eventually */
- fprintf(stderr,"unhandled syntax: $%c\n",ch);
+ error_msg("unhandled syntax: $%c",ch);
return 1;
break;
default:
return rcode;
}
+
+/* I think Erik wrote this. It looks imperfect at best */
+void grab_tty_control(void)
+{
+ pid_t initialpgrp;
+ do {
+ initialpgrp = tcgetpgrp(fileno(stderr));
+ if (initialpgrp < 0) {
+ error_msg("sh: can't access tty; job control disabled\n");
+ }
+ if (initialpgrp == -1)
+ initialpgrp = getpgrp();
+ else if (initialpgrp != getpgrp()) {
+ killpg(initialpgrp, SIGTTIN);
+ continue;
+ }
+ } while (0);
+}
+
int shell_main(int argc, char **argv)
{
int opt;
FILE *input;
struct jobset joblist_end = { NULL, NULL };
- job_list = &joblist_end;
+ char **e = environ;
+
+ /* FIXME */
+ fprintf(stderr, "sizeof(map)=%d\n", sizeof(map));
- last_return_code=EXIT_SUCCESS;
/* XXX what should these be while sourcing /etc/profile? */
global_argc = argc;
global_argv = argv;
+
+ /* (re?) initialize globals. Sometimes shell_main() ends up calling
+ * shell_main(), therefore we cannot rely on the BSS to zero out this
+ * stuff. Reset these to 0 every time. */
+ ifs = NULL;
+ memset(map,0,sizeof(map));
+ fake_mode = 0;
+ interactive = 0;
+ close_me_head = NULL;
+ last_bg_pid = 0;
+
+ /* Initialize some more globals to non-zero values */
+ set_cwd();
+ job_list = &joblist_end;
+#ifdef BB_FEATURE_COMMAND_EDITING
+ cmdedit_set_initial_prompt();
+#else
+ PS1 = NULL;
+#endif
+ PS2 = "> ";
+
+ /* initialize our shell local variables with the values
+ * currently living in the environment */
+ if (e) {
+ for (; *e; e++)
+ set_local_var(*e, 2); /* without call putenv() */
+ }
+
+ last_return_code=EXIT_SUCCESS;
+
+ /* If we get started under a job aware app (like bash
+ * for example), make sure we are now in charge so we
+ * don't fight over who gets the foreground */
/* don't pay any attention to this signal; it just confuses
things and isn't really meant for shells anyway */
signal(SIGTTOU, SIG_IGN);
+ setpgid(0, getpid());
+ tcsetpgrp(fileno(stderr), getpid());
if (argv[0] && argv[0][0] == '-') {
debug_printf("\nsourcing /etc/profile\n");
}
input=stdin;
- /* initialize the cwd -- this is never freed...*/
- cwd = xgetcwd(0);
-#ifdef BB_FEATURE_COMMAND_EDITING
- cmdedit_set_initial_prompt();
-#else
- PS1 = NULL;
-#endif
-
while ((opt = getopt(argc, argv, "c:xif")) > 0) {
switch (opt) {
case 'c':
fake_mode++;
break;
default:
+#ifndef BB_VER
fprintf(stderr, "Usage: sh [FILE]...\n"
" or: sh -c command [args]...\n\n");
exit(EXIT_FAILURE);
+#else
+ show_usage();
+#endif
}
}
/* A shell is interactive if the `-i' flag was given, or if all of
if (interactive) {
/* Looks like they want an interactive shell */
fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n");
+ grab_tty_control();
+ }
+ if (argv[optind]==NULL) {
opt=parse_file_outer(stdin);
goto final_return;
}
projects / oweals / busybox.git / blobdiff