1 /* vi: set sw=4 ts=4: */
3 * sh.c -- a prototype Bourne shell grammar parser
4 * Intended to follow the original Thompson and Ritchie
5 * "small and simple is beautiful" philosophy, which
6 * incidentally is a good match to today's BusyBox.
8 * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
11 * The parser routines proper are all original material, first
12 * written Dec 2000 and Jan 2001 by Larry Doolittle. The
13 * execution engine, the builtins, and much of the underlying
14 * support has been adapted from busybox-0.49pre's lash, which is
15 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
16 * written by Erik Andersen <andersen@codepoet.org>. That, in turn,
17 * is based in part on ladsh.c, by Michael K. Johnson and Erik W.
18 * Troan, which they placed in the public domain. I don't know
19 * how much of the Johnson/Troan code has survived the repeated
23 * simple_itoa() was lifted from boa-0.93.15
24 * b_addchr() derived from similar w_addchar function in glibc-2.2
25 * setup_redirect(), redirect_opt_num(), and big chunks of main()
26 * and many builtins derived from contributions by Erik Andersen
27 * miscellaneous bugfixes from Matt Kraai
29 * There are two big (and related) architecture differences between
30 * this parser and the lash parser. One is that this version is
31 * actually designed from the ground up to understand nearly all
32 * of the Bourne grammar. The second, consequential change is that
33 * the parser and input reader have been turned inside out. Now,
34 * the parser is in control, and asks for input as needed. The old
35 * way had the input reader in control, and it asked for parsing to
36 * take place as needed. The new way makes it much easier to properly
37 * handle the recursion implicit in the various substitutions, especially
38 * across continuation lines.
40 * Bash grammar not implemented: (how many of these were in original sh?)
41 * $@ (those sure look like weird quoting rules)
43 * ! negation operator for pipes
44 * &> and >& redirection of stdout+stderr
47 * fancy forms of Parameter Expansion
49 * Arithmetic Expansion
50 * <(list) and >(list) Process Substitution
51 * reserved words: case, esac, select, function
52 * Here Documents ( << word )
55 * job handling woefully incomplete and buggy
56 * reserved word execution woefully incomplete and buggy
58 * port selected bugfixes from post-0.49 busybox lash - done?
59 * finish implementing reserved words: for, while, until, do, done
60 * change { and } from special chars to reserved words
61 * builtins: break, continue, eval, return, set, trap, ulimit
63 * handle children going into background
64 * clean up recognition of null pipes
65 * check setting of global_argc and global_argv
66 * control-C handling, probably with longjmp
67 * follow IFS rules more precisely, including update semantics
68 * figure out what to do with backslash-newline
69 * explain why we use signal instead of sigaction
70 * propagate syntax errors, die on resource errors?
71 * continuation lines, both explicit and implicit - done?
72 * memory leak finding and plugging - done?
73 * more testing, especially quoting rules and redirection
74 * document how quoting rules not precisely followed for variable assignments
75 * maybe change map[] to use 2-bit entries
76 * (eventually) remove all the printf's
78 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
80 #include <ctype.h> /* isalpha, isdigit */
81 #include <unistd.h> /* getpid */
82 #include <stdlib.h> /* getenv, atoi */
83 #include <string.h> /* strchr */
84 #include <stdio.h> /* popen etc. */
85 #include <glob.h> /* glob, of course */
86 #include <stdarg.h> /* va_list */
89 #include <getopt.h> /* should be pretty obvious */
91 #include <sys/stat.h> /* ulimit */
92 #include <sys/types.h>
96 /* #include <dmalloc.h> */
97 /* #define DEBUG_SHELL */
103 #define bb_applet_name "hush"
104 #include "standalone.h"
105 #define hush_main main
106 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
109 #define SPECIAL_VAR_SYMBOL 03
110 #define FLAG_EXIT_FROM_LOOP 1
111 #define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
112 #define FLAG_REPARSING (1 << 2) /* >=2nd pass */
116 REDIRECT_OVERWRITE = 2,
122 /* The descrip member of this structure is only used to make debugging
124 static const struct {int mode; int default_fd; const char *descrip;} redir_table[] = {
126 { O_RDONLY, 0, "<" },
127 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
128 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
129 { O_RDONLY, -1, "<<" },
140 /* might eventually control execution */
157 #define FLAG_END (1<<RES_NONE)
158 #define FLAG_IF (1<<RES_IF)
159 #define FLAG_THEN (1<<RES_THEN)
160 #define FLAG_ELIF (1<<RES_ELIF)
161 #define FLAG_ELSE (1<<RES_ELSE)
162 #define FLAG_FI (1<<RES_FI)
163 #define FLAG_FOR (1<<RES_FOR)
164 #define FLAG_WHILE (1<<RES_WHILE)
165 #define FLAG_UNTIL (1<<RES_UNTIL)
166 #define FLAG_DO (1<<RES_DO)
167 #define FLAG_DONE (1<<RES_DONE)
168 #define FLAG_IN (1<<RES_IN)
169 #define FLAG_START (1<<RES_XXXX)
171 /* This holds pointers to the various results of parsing */
173 struct child_prog *child;
174 struct pipe *list_head;
176 struct redir_struct *pending_redirect;
178 int old_flag; /* for figuring out valid reserved words */
179 struct p_context *stack;
180 int type; /* define type of parser : ";$" common or special symbol */
181 /* How about quoting status? */
184 struct redir_struct {
185 redir_type type; /* type of redirection */
186 int fd; /* file descriptor being redirected */
187 int dup; /* -1, or file descriptor being duplicated */
188 struct redir_struct *next; /* pointer to the next redirect in the list */
189 glob_t word; /* *word.gl_pathv is the filename */
193 pid_t pid; /* 0 if exited */
194 char **argv; /* program name and arguments */
195 struct pipe *group; /* if non-NULL, first in group or subshell */
196 int subshell; /* flag, non-zero if group must be forked */
197 struct redir_struct *redirects; /* I/O redirections */
198 glob_t glob_result; /* result of parameter globbing */
199 int is_stopped; /* is the program currently running? */
200 struct pipe *family; /* pointer back to the child's parent pipe */
201 int sp; /* number of SPECIAL_VAR_SYMBOL */
206 int jobid; /* job number */
207 int num_progs; /* total number of programs in job */
208 int running_progs; /* number of programs running */
209 char *text; /* name of job */
210 char *cmdbuf; /* buffer various argv's point into */
211 pid_t pgrp; /* process group ID for the job */
212 struct child_prog *progs; /* array of commands in pipe */
213 struct pipe *next; /* to track background commands */
214 int stopped_progs; /* number of programs alive, but stopped */
215 int job_context; /* bitmask defining current context */
216 pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
217 reserved_style r_mode; /* supports if, for, while, until */
222 struct close_me *next;
230 struct variables *next;
233 /* globals, connect us to the outside world
234 * the first three support $?, $#, and $1 */
235 static char **global_argv;
236 static int global_argc;
237 static int last_return_code;
238 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
240 /* "globals" within this file */
242 static unsigned char map[256];
243 static int fake_mode;
244 static int interactive;
245 static struct close_me *close_me_head;
246 static const char *cwd;
247 static struct pipe *job_list;
248 static unsigned int last_bg_pid;
249 static int last_jobid;
250 static unsigned int shell_terminal;
253 static struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
254 static struct variables *top_vars = &shell_ver;
257 #define B_CHUNK (100)
267 #define NULL_O_STRING {NULL,0,0,0,0}
268 /* used for initialization:
269 o_string foo = NULL_O_STRING; */
271 /* I can almost use ordinary FILE *. Is open_memstream() universally
272 * available? Where is it documented? */
279 int (*get) (struct in_str *);
280 int (*peek) (struct in_str *);
282 #define b_getch(input) ((input)->get(input))
283 #define b_peek(input) ((input)->peek(input))
285 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
287 struct built_in_command {
288 const char *cmd; /* name */
289 const char *descr; /* description */
290 int (*function) (struct child_prog *); /* function ptr */
293 /* belongs in busybox.h */
294 static inline int max(int a, int b) {
298 /* This should be in utility.c */
300 static void debug_printf(const char *format, ...)
303 va_start(args, format);
304 vfprintf(stderr, format, args);
308 static inline void debug_printf(const char *format ATTRIBUTE_UNUSED, ...) { }
310 #define final_printf debug_printf
312 static void __syntax(char *file, int line) {
313 bb_error_msg("syntax error %s:%d", file, line);
315 #define syntax() __syntax(__FILE__, __LINE__)
317 /* Index of subroutines: */
318 /* function prototypes for builtins */
319 static int builtin_cd(struct child_prog *child);
320 static int builtin_env(struct child_prog *child);
321 static int builtin_eval(struct child_prog *child);
322 static int builtin_exec(struct child_prog *child);
323 static int builtin_exit(struct child_prog *child);
324 static int builtin_export(struct child_prog *child);
325 static int builtin_fg_bg(struct child_prog *child);
326 static int builtin_help(struct child_prog *child);
327 static int builtin_jobs(struct child_prog *child);
328 static int builtin_pwd(struct child_prog *child);
329 static int builtin_read(struct child_prog *child);
330 static int builtin_set(struct child_prog *child);
331 static int builtin_shift(struct child_prog *child);
332 static int builtin_source(struct child_prog *child);
333 static int builtin_umask(struct child_prog *child);
334 static int builtin_unset(struct child_prog *child);
335 static int builtin_not_written(struct child_prog *child);
336 /* o_string manipulation: */
337 static int b_check_space(o_string *o, int len);
338 static int b_addchr(o_string *o, int ch);
339 static void b_reset(o_string *o);
340 static int b_addqchr(o_string *o, int ch, int quote);
341 static int b_adduint(o_string *o, unsigned int i);
342 /* in_str manipulations: */
343 static int static_get(struct in_str *i);
344 static int static_peek(struct in_str *i);
345 static int file_get(struct in_str *i);
346 static int file_peek(struct in_str *i);
347 static void setup_file_in_str(struct in_str *i, FILE *f);
348 static void setup_string_in_str(struct in_str *i, const char *s);
349 /* close_me manipulations: */
350 static void mark_open(int fd);
351 static void mark_closed(int fd);
352 static void close_all(void);
353 /* "run" the final data structures: */
354 static char *indenter(int i);
355 static int free_pipe_list(struct pipe *head, int indent);
356 static int free_pipe(struct pipe *pi, int indent);
357 /* really run the final data structures: */
358 static int setup_redirects(struct child_prog *prog, int squirrel[]);
359 static int run_list_real(struct pipe *pi);
360 static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN;
361 static int run_pipe_real(struct pipe *pi);
362 /* extended glob support: */
363 static int globhack(const char *src, int flags, glob_t *pglob);
364 static int glob_needed(const char *s);
365 static int xglob(o_string *dest, int flags, glob_t *pglob);
366 /* variable assignment: */
367 static int is_assignment(const char *s);
368 /* data structure manipulation: */
369 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
370 static void initialize_context(struct p_context *ctx);
371 static int done_word(o_string *dest, struct p_context *ctx);
372 static int done_command(struct p_context *ctx);
373 static int done_pipe(struct p_context *ctx, pipe_style type);
374 /* primary string parsing: */
375 static int redirect_dup_num(struct in_str *input);
376 static int redirect_opt_num(o_string *o);
377 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
378 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
379 static char *lookup_param(char *src);
380 static char *make_string(char **inp);
381 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
382 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
383 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
385 static int parse_stream_outer(struct in_str *inp, int flag);
386 static int parse_string_outer(const char *s, int flag);
387 static int parse_file_outer(FILE *f);
388 /* job management: */
389 static int checkjobs(struct pipe* fg_pipe);
390 static void insert_bg_job(struct pipe *pi);
391 static void remove_bg_job(struct pipe *pi);
392 /* local variable support */
393 static char **make_list_in(char **inp, char *name);
394 static char *insert_var_value(char *inp);
395 static char *get_local_var(const char *var);
396 static void unset_local_var(const char *name);
397 static int set_local_var(const char *s, int flg_export);
399 /* Table of built-in functions. They can be forked or not, depending on
400 * context: within pipes, they fork. As simple commands, they do not.
401 * When used in non-forking context, they can change global variables
402 * in the parent shell process. If forked, of course they can not.
403 * For example, 'unset foo | whatever' will parse and run, but foo will
404 * still be set at the end. */
405 static const struct built_in_command bltins[] = {
406 {"bg", "Resume a job in the background", builtin_fg_bg},
407 {"break", "Exit for, while or until loop", builtin_not_written},
408 {"cd", "Change working directory", builtin_cd},
409 {"continue", "Continue for, while or until loop", builtin_not_written},
410 {"env", "Print all environment variables", builtin_env},
411 {"eval", "Construct and run shell command", builtin_eval},
412 {"exec", "Exec command, replacing this shell with the exec'd process",
414 {"exit", "Exit from shell()", builtin_exit},
415 {"export", "Set environment variable", builtin_export},
416 {"fg", "Bring job into the foreground", builtin_fg_bg},
417 {"jobs", "Lists the active jobs", builtin_jobs},
418 {"pwd", "Print current directory", builtin_pwd},
419 {"read", "Input environment variable", builtin_read},
420 {"return", "Return from a function", builtin_not_written},
421 {"set", "Set/unset shell local variables", builtin_set},
422 {"shift", "Shift positional parameters", builtin_shift},
423 {"trap", "Trap signals", builtin_not_written},
424 {"ulimit","Controls resource limits", builtin_not_written},
425 {"umask","Sets file creation mask", builtin_umask},
426 {"unset", "Unset environment variable", builtin_unset},
427 {".", "Source-in and run commands in a file", builtin_source},
428 {"help", "List shell built-in commands", builtin_help},
432 static const char *set_cwd(void)
434 if(cwd==bb_msg_unknown)
435 cwd = NULL; /* xgetcwd(arg) called free(arg) */
436 cwd = xgetcwd((char *)cwd);
438 cwd = bb_msg_unknown;
442 /* built-in 'eval' handler */
443 static int builtin_eval(struct child_prog *child)
446 int rcode = EXIT_SUCCESS;
448 if (child->argv[1]) {
449 str = make_string(child->argv + 1);
450 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
451 FLAG_PARSE_SEMICOLON);
453 rcode = last_return_code;
458 /* built-in 'cd <path>' handler */
459 static int builtin_cd(struct child_prog *child)
462 if (child->argv[1] == NULL)
463 newdir = getenv("HOME");
465 newdir = child->argv[1];
467 printf("cd: %s: %s\n", newdir, strerror(errno));
474 /* built-in 'env' handler */
475 static int builtin_env(struct child_prog *dummy ATTRIBUTE_UNUSED)
478 if (e == NULL) return EXIT_FAILURE;
485 /* built-in 'exec' handler */
486 static int builtin_exec(struct child_prog *child)
488 if (child->argv[1] == NULL)
489 return EXIT_SUCCESS; /* Really? */
495 /* built-in 'exit' handler */
496 static int builtin_exit(struct child_prog *child)
498 if (child->argv[1] == NULL)
499 exit(last_return_code);
500 exit (atoi(child->argv[1]));
503 /* built-in 'export VAR=value' handler */
504 static int builtin_export(struct child_prog *child)
507 char *name = child->argv[1];
510 return (builtin_env(child));
516 char *value = strchr(name, '=');
520 /* They are exporting something without an =VALUE */
522 value = get_local_var(name);
524 size_t ln = strlen(name);
526 tmp = realloc(name, ln+strlen(value)+2);
530 sprintf(tmp+ln, "=%s", value);
534 /* bash does not return an error when trying to export
535 * an undefined variable. Do likewise. */
541 bb_perror_msg("export");
543 res = set_local_var(name, 1);
550 /* built-in 'fg' and 'bg' handler */
551 static int builtin_fg_bg(struct child_prog *child)
554 struct pipe *pi=NULL;
558 /* If they gave us no args, assume they want the last backgrounded task */
559 if (!child->argv[1]) {
560 for (pi = job_list; pi; pi = pi->next) {
561 if (pi->jobid == last_jobid) {
566 bb_error_msg("%s: no current job", child->argv[0]);
570 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
571 bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
574 for (pi = job_list; pi; pi = pi->next) {
575 if (pi->jobid == jobnum) {
580 bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
585 if (*child->argv[0] == 'f') {
586 /* Put the job into the foreground. */
587 tcsetpgrp(shell_terminal, pi->pgrp);
590 /* Restart the processes in the job */
591 for (i = 0; i < pi->num_progs; i++)
592 pi->progs[i].is_stopped = 0;
594 if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
598 bb_perror_msg("kill (SIGCONT)");
602 pi->stopped_progs = 0;
606 /* built-in 'help' handler */
607 static int builtin_help(struct child_prog *dummy ATTRIBUTE_UNUSED)
609 const struct built_in_command *x;
611 printf("\nBuilt-in commands:\n");
612 printf("-------------------\n");
613 for (x = bltins; x->cmd; x++) {
616 printf("%s\t%s\n", x->cmd, x->descr);
622 /* built-in 'jobs' handler */
623 static int builtin_jobs(struct child_prog *child ATTRIBUTE_UNUSED)
628 for (job = job_list; job; job = job->next) {
629 if (job->running_progs == job->stopped_progs)
630 status_string = "Stopped";
632 status_string = "Running";
634 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
640 /* built-in 'pwd' handler */
641 static int builtin_pwd(struct child_prog *dummy ATTRIBUTE_UNUSED)
647 /* built-in 'read VAR' handler */
648 static int builtin_read(struct child_prog *child)
652 if (child->argv[1]) {
656 string[0] = 0; /* In case stdin has only EOF */
658 fgets(string, sizeof(string), stdin);
660 var = malloc(strlen(child->argv[1])+strlen(string)+2);
662 sprintf(var, "%s=%s", child->argv[1], string);
663 res = set_local_var(var, 0);
667 fprintf(stderr, "read: %m\n");
668 free(var); /* So not move up to avoid breaking errno */
671 do res=getchar(); while(res!='\n' && res!=EOF);
676 /* built-in 'set VAR=value' handler */
677 static int builtin_set(struct child_prog *child)
679 char *temp = child->argv[1];
683 for(e = top_vars; e; e=e->next)
684 printf("%s=%s\n", e->name, e->value);
686 set_local_var(temp, 0);
692 /* Built-in 'shift' handler */
693 static int builtin_shift(struct child_prog *child)
696 if (child->argv[1]) {
697 n=atoi(child->argv[1]);
699 if (n>=0 && n<global_argc) {
700 /* XXX This probably breaks $0 */
709 /* Built-in '.' handler (read-in and execute commands from file) */
710 static int builtin_source(struct child_prog *child)
715 if (child->argv[1] == NULL)
718 /* XXX search through $PATH is missing */
719 input = fopen(child->argv[1], "r");
721 bb_error_msg("Couldn't open file '%s'", child->argv[1]);
725 /* Now run the file */
726 /* XXX argv and argc are broken; need to save old global_argv
727 * (pointer only is OK!) on this stack frame,
728 * set global_argv=child->argv+1, recurse, and restore. */
729 mark_open(fileno(input));
730 status = parse_file_outer(input);
731 mark_closed(fileno(input));
736 static int builtin_umask(struct child_prog *child)
739 const char *arg = child->argv[1];
742 new_umask=strtoul(arg, &end, 8);
743 if (*end!='\0' || end == arg) {
747 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
753 /* built-in 'unset VAR' handler */
754 static int builtin_unset(struct child_prog *child)
756 /* bash returned already true */
757 unset_local_var(child->argv[1]);
761 static int builtin_not_written(struct child_prog *child)
763 printf("builtin_%s not written\n",child->argv[0]);
767 static int b_check_space(o_string *o, int len)
769 /* It would be easy to drop a more restrictive policy
770 * in here, such as setting a maximum string length */
771 if (o->length + len > o->maxlen) {
772 char *old_data = o->data;
773 /* assert (data == NULL || o->maxlen != 0); */
774 o->maxlen += max(2*len, B_CHUNK);
775 o->data = realloc(o->data, 1 + o->maxlen);
776 if (o->data == NULL) {
780 return o->data == NULL;
783 static int b_addchr(o_string *o, int ch)
785 debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
786 if (b_check_space(o, 1)) return B_NOSPAC;
787 o->data[o->length] = ch;
789 o->data[o->length] = '\0';
793 static void b_reset(o_string *o)
797 if (o->data != NULL) *o->data = '\0';
800 static void b_free(o_string *o)
808 /* My analysis of quoting semantics tells me that state information
809 * is associated with a destination, not a source.
811 static int b_addqchr(o_string *o, int ch, int quote)
813 if (quote && strchr("*?[\\",ch)) {
815 rc = b_addchr(o, '\\');
818 return b_addchr(o, ch);
821 /* belongs in utility.c */
822 static char *simple_itoa(unsigned int i)
824 /* 21 digits plus null terminator, good for 64-bit or smaller ints */
825 static char local[22];
826 char *p = &local[21];
835 static int b_adduint(o_string *o, unsigned int i)
838 char *p = simple_itoa(i);
839 /* no escape checking necessary */
840 do r=b_addchr(o, *p++); while (r==0 && *p);
844 static int static_get(struct in_str *i)
847 if (ch=='\0') return EOF;
851 static int static_peek(struct in_str *i)
856 static inline void cmdedit_set_initial_prompt(void)
858 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
867 static inline void setup_prompt_string(int promptmode, char **prompt_str)
869 debug_printf("setup_prompt_string %d ",promptmode);
870 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
871 /* Set up the prompt */
872 if (promptmode == 1) {
874 PS1=xmalloc(strlen(cwd)+4);
875 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# ");
881 *prompt_str = (promptmode==1)? PS1 : PS2;
883 debug_printf("result %s\n",*prompt_str);
886 static void get_user_input(struct in_str *i)
889 static char the_command[BUFSIZ];
891 setup_prompt_string(i->promptmode, &prompt_str);
892 #ifdef CONFIG_FEATURE_COMMAND_EDITING
894 ** enable command line editing only while a command line
895 ** is actually being read; otherwise, we'll end up bequeathing
896 ** atexit() handlers and other unwanted stuff to our
897 ** child processes (rob@sysgo.de)
899 cmdedit_read_input(prompt_str, the_command);
901 fputs(prompt_str, stdout);
903 the_command[0]=fgetc(i->file);
910 /* This is the magic location that prints prompts
911 * and gets data back from the user */
912 static int file_get(struct in_str *i)
917 /* If there is data waiting, eat it up */
921 /* need to double check i->file because we might be doing something
922 * more complicated by now, like sourcing or substituting. */
923 if (i->__promptme && interactive && i->file == stdin) {
924 while(! i->p || (interactive && strlen(i->p)==0) ) {
936 debug_printf("b_getch: got a %d\n", ch);
938 if (ch == '\n') i->__promptme=1;
942 /* All the callers guarantee this routine will never be
943 * used right after a newline, so prompting is not needed.
945 static int file_peek(struct in_str *i)
950 i->peek_buf[0] = fgetc(i->file);
951 i->peek_buf[1] = '\0';
953 debug_printf("b_peek: got a %d\n", *i->p);
958 static void setup_file_in_str(struct in_str *i, FILE *f)
968 static void setup_string_in_str(struct in_str *i, const char *s)
970 i->peek = static_peek;
977 static void mark_open(int fd)
979 struct close_me *new = xmalloc(sizeof(struct close_me));
981 new->next = close_me_head;
985 static void mark_closed(int fd)
987 struct close_me *tmp;
988 if (close_me_head == NULL || close_me_head->fd != fd)
989 bb_error_msg_and_die("corrupt close_me");
991 close_me_head = close_me_head->next;
995 static void close_all(void)
998 for (c=close_me_head; c; c=c->next) {
1001 close_me_head = NULL;
1004 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1005 * and stderr if they are redirected. */
1006 static int setup_redirects(struct child_prog *prog, int squirrel[])
1009 struct redir_struct *redir;
1011 for (redir=prog->redirects; redir; redir=redir->next) {
1012 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1013 /* something went wrong in the parse. Pretend it didn't happen */
1016 if (redir->dup == -1) {
1017 mode=redir_table[redir->type].mode;
1018 openfd = open(redir->word.gl_pathv[0], mode, 0666);
1020 /* this could get lost if stderr has been redirected, but
1021 bash and ash both lose it as well (though zsh doesn't!) */
1022 bb_perror_msg("error opening %s", redir->word.gl_pathv[0]);
1026 openfd = redir->dup;
1029 if (openfd != redir->fd) {
1030 if (squirrel && redir->fd < 3) {
1031 squirrel[redir->fd] = dup(redir->fd);
1036 dup2(openfd, redir->fd);
1037 if (redir->dup == -1)
1045 static void restore_redirects(int squirrel[])
1048 for (i=0; i<3; i++) {
1051 /* No error checking. I sure wouldn't know what
1052 * to do with an error if I found one! */
1060 /* XXX no exit() here. If you don't exec, use _exit instead.
1061 * The at_exit handlers apparently confuse the calling process,
1062 * in particular stdin handling. Not sure why? */
1063 static void pseudo_exec(struct child_prog *child)
1067 const struct built_in_command *x;
1069 for (i=0; is_assignment(child->argv[i]); i++) {
1070 debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1071 p = insert_var_value(child->argv[i]);
1073 if (p != child->argv[i]) free(p);
1075 child->argv+=i; /* XXX this hack isn't so horrible, since we are about
1076 to exit, and therefore don't need to keep data
1077 structures consistent for free() use. */
1078 /* If a variable is assigned in a forest, and nobody listens,
1079 * was it ever really set?
1081 if (child->argv[0] == NULL) {
1082 _exit(EXIT_SUCCESS);
1086 * Check if the command matches any of the builtins.
1087 * Depending on context, this might be redundant. But it's
1088 * easier to waste a few CPU cycles than it is to figure out
1089 * if this is one of those cases.
1091 for (x = bltins; x->cmd; x++) {
1092 if (strcmp(child->argv[0], x->cmd) == 0 ) {
1093 debug_printf("builtin exec %s\n", child->argv[0]);
1094 rcode = x->function(child);
1100 /* Check if the command matches any busybox internal commands
1102 * FIXME: This feature is not 100% safe, since
1103 * BusyBox is not fully reentrant, so we have no guarantee the things
1104 * from the .bss are still zeroed, or that things from .data are still
1105 * at their defaults. We could exec ourself from /proc/self/exe, but I
1106 * really dislike relying on /proc for things. We could exec ourself
1107 * from global_argv[0], but if we are in a chroot, we may not be able
1108 * to find ourself... */
1109 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1112 char** argv_l=child->argv;
1113 char *name = child->argv[0];
1115 /* Count argc for use in a second... */
1116 for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1118 debug_printf("running applet %s\n", name);
1119 run_applet_by_name(name, argc_l, child->argv);
1122 debug_printf("exec of %s\n",child->argv[0]);
1123 execvp(child->argv[0],child->argv);
1124 bb_perror_msg("couldn't exec: %s",child->argv[0]);
1126 } else if (child->group) {
1127 debug_printf("runtime nesting to group\n");
1128 interactive=0; /* crucial!!!! */
1129 rcode = run_list_real(child->group);
1130 /* OK to leak memory by not calling free_pipe_list,
1131 * since this process is about to exit */
1134 /* Can happen. See what bash does with ">foo" by itself. */
1135 debug_printf("trying to pseudo_exec null command\n");
1136 _exit(EXIT_SUCCESS);
1140 static void insert_bg_job(struct pipe *pi)
1142 struct pipe *thejob;
1144 /* Linear search for the ID of the job to use */
1146 for (thejob = job_list; thejob; thejob = thejob->next)
1147 if (thejob->jobid >= pi->jobid)
1148 pi->jobid = thejob->jobid + 1;
1150 /* add thejob to the list of running jobs */
1152 thejob = job_list = xmalloc(sizeof(*thejob));
1154 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1155 thejob->next = xmalloc(sizeof(*thejob));
1156 thejob = thejob->next;
1159 /* physically copy the struct job */
1160 memcpy(thejob, pi, sizeof(struct pipe));
1161 thejob->next = NULL;
1162 thejob->running_progs = thejob->num_progs;
1163 thejob->stopped_progs = 0;
1164 thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1166 //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0])
1168 char *bar=thejob->text;
1169 char **foo=pi->progs[0].argv;
1170 while(foo && *foo) {
1171 bar += sprintf(bar, "%s ", *foo++);
1175 /* we don't wait for background thejobs to return -- append it
1176 to the list of backgrounded thejobs and leave it alone */
1177 printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1178 last_bg_pid = thejob->progs[0].pid;
1179 last_jobid = thejob->jobid;
1182 /* remove a backgrounded job */
1183 static void remove_bg_job(struct pipe *pi)
1185 struct pipe *prev_pipe;
1187 if (pi == job_list) {
1188 job_list = pi->next;
1190 prev_pipe = job_list;
1191 while (prev_pipe->next != pi)
1192 prev_pipe = prev_pipe->next;
1193 prev_pipe->next = pi->next;
1196 last_jobid = job_list->jobid;
1200 pi->stopped_progs = 0;
1205 /* Checks to see if any processes have exited -- if they
1206 have, figure out why and see if a job has completed */
1207 static int checkjobs(struct pipe* fg_pipe)
1215 attributes = WUNTRACED;
1216 if (fg_pipe==NULL) {
1217 attributes |= WNOHANG;
1220 while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1223 for (i=0; i < fg_pipe->num_progs; i++) {
1224 if (fg_pipe->progs[i].pid == childpid) {
1225 if (i==fg_pipe->num_progs-1)
1226 rcode=WEXITSTATUS(status);
1227 (fg_pipe->num_progs)--;
1233 for (pi = job_list; pi; pi = pi->next) {
1235 while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1238 if (prognum < pi->num_progs)
1243 debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1247 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1249 pi->running_progs--;
1250 pi->progs[prognum].pid = 0;
1252 if (!pi->running_progs) {
1253 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1258 pi->stopped_progs++;
1259 pi->progs[prognum].is_stopped = 1;
1262 /* Printing this stuff is a pain, since it tends to
1263 * overwrite the prompt an inconveinient moments. So
1265 if (pi->stopped_progs == pi->num_progs) {
1266 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1272 if (childpid == -1 && errno != ECHILD)
1273 bb_perror_msg("waitpid");
1275 /* move the shell to the foreground */
1276 //if (interactive && tcsetpgrp(shell_terminal, getpgid(0)))
1277 // bb_perror_msg("tcsetpgrp-2");
1281 /* Figure out our controlling tty, checking in order stderr,
1282 * stdin, and stdout. If check_pgrp is set, also check that
1283 * we belong to the foreground process group associated with
1284 * that tty. The value of shell_terminal is needed in order to call
1285 * tcsetpgrp(shell_terminal, ...); */
1287 static void controlling_tty(int check_pgrp)
1291 if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1292 && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1293 && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1294 goto shell_terminal_error;
1296 if (check_pgrp && curpgrp != getpgid(0))
1297 goto shell_terminal_error;
1301 shell_terminal_error:
1302 shell_terminal = -1;
1307 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1308 * to finish. See checkjobs().
1310 * return code is normally -1, when the caller has to wait for children
1311 * to finish to determine the exit status of the pipe. If the pipe
1312 * is a simple builtin command, however, the action is done by the
1313 * time run_pipe_real returns, and the exit code is provided as the
1316 * The input of the pipe is always stdin, the output is always
1317 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1318 * because it tries to avoid running the command substitution in
1319 * subshell, when that is in fact necessary. The subshell process
1320 * now has its stdout directed to the input of the appropriate pipe,
1321 * so this routine is noticeably simpler.
1323 static int run_pipe_real(struct pipe *pi)
1326 int nextin, nextout;
1327 int pipefds[2]; /* pipefds[0] is for reading */
1328 struct child_prog *child;
1329 const struct built_in_command *x;
1335 /* Check if this is a simple builtin (not part of a pipe).
1336 * Builtins within pipes have to fork anyway, and are handled in
1337 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1339 if (pi->num_progs == 1) child = & (pi->progs[0]);
1340 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1341 int squirrel[] = {-1, -1, -1};
1343 debug_printf("non-subshell grouping\n");
1344 setup_redirects(child, squirrel);
1345 /* XXX could we merge code with following builtin case,
1346 * by creating a pseudo builtin that calls run_list_real? */
1347 rcode = run_list_real(child->group);
1348 restore_redirects(squirrel);
1350 } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1351 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1352 if (i!=0 && child->argv[i]==NULL) {
1353 /* assignments, but no command: set the local environment */
1354 for (i=0; child->argv[i]!=NULL; i++) {
1356 /* Ok, this case is tricky. We have to decide if this is a
1357 * local variable, or an already exported variable. If it is
1358 * already exported, we have to export the new value. If it is
1359 * not exported, we need only set this as a local variable.
1360 * This junk is all to decide whether or not to export this
1364 name = bb_xstrdup(child->argv[i]);
1365 debug_printf("Local environment set: %s\n", name);
1366 value = strchr(name, '=');
1369 if ( get_local_var(name)) {
1373 p = insert_var_value(child->argv[i]);
1374 set_local_var(p, export_me);
1375 if (p != child->argv[i]) free(p);
1377 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1379 for (i = 0; is_assignment(child->argv[i]); i++) {
1380 p = insert_var_value(child->argv[i]);
1382 if (p != child->argv[i]) {
1390 str = make_string((child->argv + i));
1391 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1393 return last_return_code;
1395 for (x = bltins; x->cmd; x++) {
1396 if (strcmp(child->argv[i], x->cmd) == 0 ) {
1397 int squirrel[] = {-1, -1, -1};
1399 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1400 debug_printf("magic exec\n");
1401 setup_redirects(child,NULL);
1402 return EXIT_SUCCESS;
1404 debug_printf("builtin inline %s\n", child->argv[0]);
1405 /* XXX setup_redirects acts on file descriptors, not FILEs.
1406 * This is perfect for work that comes after exec().
1407 * Is it really safe for inline use? Experimentally,
1408 * things seem to work with glibc. */
1409 setup_redirects(child, squirrel);
1410 child->argv+=i; /* XXX horrible hack */
1411 rcode = x->function(child);
1412 child->argv-=i; /* XXX restore hack so free() can work right */
1413 restore_redirects(squirrel);
1419 for (i = 0; i < pi->num_progs; i++) {
1420 child = & (pi->progs[i]);
1422 /* pipes are inserted between pairs of commands */
1423 if ((i + 1) < pi->num_progs) {
1424 if (pipe(pipefds)<0) bb_perror_msg_and_die("pipe");
1425 nextout = pipefds[1];
1431 /* XXX test for failed fork()? */
1432 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
1433 if (!(child->pid = fork()))
1435 if (!(child->pid = vfork()))
1438 /* Set the handling for job control signals back to the default. */
1439 signal(SIGINT, SIG_DFL);
1440 signal(SIGQUIT, SIG_DFL);
1441 signal(SIGTERM, SIG_DFL);
1442 signal(SIGTSTP, SIG_DFL);
1443 signal(SIGTTIN, SIG_DFL);
1444 signal(SIGTTOU, SIG_DFL);
1445 signal(SIGCHLD, SIG_DFL);
1457 if (pipefds[0]!=-1) {
1458 close(pipefds[0]); /* opposite end of our output pipe */
1461 /* Like bash, explicit redirects override pipes,
1462 * and the pipe fd is available for dup'ing. */
1463 setup_redirects(child,NULL);
1465 if (interactive && pi->followup!=PIPE_BG) {
1466 /* If we (the child) win the race, put ourselves in the process
1467 * group whose leader is the first process in this pipe. */
1469 pi->pgrp = getpid();
1471 if (setpgid(0, pi->pgrp) == 0) {
1472 tcsetpgrp(2, pi->pgrp);
1480 /* put our child in the process group whose leader is the
1481 first process in this pipe */
1483 pi->pgrp = child->pid;
1485 /* Don't check for errors. The child may be dead already,
1486 * in which case setpgid returns error code EACCES. */
1487 setpgid(child->pid, pi->pgrp);
1494 /* If there isn't another process, nextin is garbage
1495 but it doesn't matter */
1496 nextin = pipefds[0];
1501 static int run_list_real(struct pipe *pi)
1503 char *save_name = NULL;
1505 char **save_list = NULL;
1509 int rcode=0, flag_skip=1;
1510 int flag_restore = 0;
1511 int if_code=0, next_if_code=0; /* need double-buffer to handle elif */
1512 reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1513 /* check syntax for "for" */
1514 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1515 if ((rpipe->r_mode == RES_IN ||
1516 rpipe->r_mode == RES_FOR) &&
1517 (rpipe->next == NULL)) {
1521 if ((rpipe->r_mode == RES_IN &&
1522 (rpipe->next->r_mode == RES_IN &&
1523 rpipe->next->progs->argv != NULL))||
1524 (rpipe->r_mode == RES_FOR &&
1525 rpipe->next->r_mode != RES_IN)) {
1530 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1531 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1532 pi->r_mode == RES_FOR) {
1540 debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n", rmode, if_code, next_if_code, skip_more_in_this_rmode);
1541 if (rmode == skip_more_in_this_rmode && flag_skip) {
1542 if (pi->followup == PIPE_SEQ) flag_skip=0;
1546 skip_more_in_this_rmode = RES_XXXX;
1547 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1548 if (rmode == RES_THEN && if_code) continue;
1549 if (rmode == RES_ELSE && !if_code) continue;
1550 if (rmode == RES_ELIF && !if_code) break;
1551 if (rmode == RES_FOR && pi->num_progs) {
1553 /* if no variable values after "in" we skip "for" */
1554 if (!pi->next->progs->argv) continue;
1555 /* create list of variable values */
1556 list = make_list_in(pi->next->progs->argv,
1557 pi->progs->argv[0]);
1559 save_name = pi->progs->argv[0];
1560 pi->progs->argv[0] = NULL;
1564 free(pi->progs->argv[0]);
1568 pi->progs->argv[0] = save_name;
1569 pi->progs->glob_result.gl_pathv[0] =
1573 /* insert new value from list for variable */
1574 if (pi->progs->argv[0])
1575 free(pi->progs->argv[0]);
1576 pi->progs->argv[0] = *list++;
1577 pi->progs->glob_result.gl_pathv[0] =
1581 if (rmode == RES_IN) continue;
1582 if (rmode == RES_DO) {
1583 if (!flag_rep) continue;
1585 if ((rmode == RES_DONE)) {
1592 if (pi->num_progs == 0) continue;
1593 save_num_progs = pi->num_progs; /* save number of programs */
1594 rcode = run_pipe_real(pi);
1595 debug_printf("run_pipe_real returned %d\n",rcode);
1597 /* We only ran a builtin: rcode was set by the return value
1598 * of run_pipe_real(), and we don't need to wait for anything. */
1599 } else if (pi->followup==PIPE_BG) {
1600 /* XXX check bash's behavior with nontrivial pipes */
1601 /* XXX compute jobid */
1602 /* XXX what does bash do with attempts to background builtins? */
1604 rcode = EXIT_SUCCESS;
1607 /* move the new process group into the foreground */
1608 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1609 bb_perror_msg("tcsetpgrp-3");
1610 rcode = checkjobs(pi);
1611 /* move the shell to the foreground */
1612 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1613 bb_perror_msg("tcsetpgrp-4");
1615 rcode = checkjobs(pi);
1617 debug_printf("checkjobs returned %d\n",rcode);
1619 last_return_code=rcode;
1620 pi->num_progs = save_num_progs; /* restore number of programs */
1621 if ( rmode == RES_IF || rmode == RES_ELIF )
1622 next_if_code=rcode; /* can be overwritten a number of times */
1623 if (rmode == RES_WHILE)
1624 flag_rep = !last_return_code;
1625 if (rmode == RES_UNTIL)
1626 flag_rep = last_return_code;
1627 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1628 (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1629 skip_more_in_this_rmode=rmode;
1635 /* broken, of course, but OK for testing */
1636 static char *indenter(int i)
1638 static char blanks[]=" ";
1639 return &blanks[sizeof(blanks)-i-1];
1642 /* return code is the exit status of the pipe */
1643 static int free_pipe(struct pipe *pi, int indent)
1646 struct child_prog *child;
1647 struct redir_struct *r, *rnext;
1648 int a, i, ret_code=0;
1649 char *ind = indenter(indent);
1651 if (pi->stopped_progs > 0)
1653 final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1654 for (i=0; i<pi->num_progs; i++) {
1655 child = &pi->progs[i];
1656 final_printf("%s command %d:\n",ind,i);
1658 for (a=0,p=child->argv; *p; a++,p++) {
1659 final_printf("%s argv[%d] = %s\n",ind,a,*p);
1661 globfree(&child->glob_result);
1663 } else if (child->group) {
1664 final_printf("%s begin group (subshell:%d)\n",ind, child->subshell);
1665 ret_code = free_pipe_list(child->group,indent+3);
1666 final_printf("%s end group\n",ind);
1668 final_printf("%s (nil)\n",ind);
1670 for (r=child->redirects; r; r=rnext) {
1671 final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1673 /* guard against the case >$FOO, where foo is unset or blank */
1674 if (r->word.gl_pathv) {
1675 final_printf(" %s\n", *r->word.gl_pathv);
1679 final_printf("&%d\n", r->dup);
1684 child->redirects=NULL;
1686 free(pi->progs); /* children are an array, they get freed all at once */
1691 static int free_pipe_list(struct pipe *head, int indent)
1693 int rcode=0; /* if list has no members */
1694 struct pipe *pi, *next;
1695 char *ind = indenter(indent);
1696 for (pi=head; pi; pi=next) {
1697 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
1698 rcode = free_pipe(pi, indent);
1699 final_printf("%s pipe followup code %d\n", ind, pi->followup);
1707 /* Select which version we will use */
1708 static int run_list(struct pipe *pi)
1712 rcode = run_list_real(pi);
1714 /* free_pipe_list has the side effect of clearing memory
1715 * In the long run that function can be merged with run_list_real,
1716 * but doing that now would hobble the debugging effort. */
1717 free_pipe_list(pi,0);
1721 /* The API for glob is arguably broken. This routine pushes a non-matching
1722 * string into the output structure, removing non-backslashed backslashes.
1723 * If someone can prove me wrong, by performing this function within the
1724 * original glob(3) api, feel free to rewrite this routine into oblivion.
1725 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
1726 * XXX broken if the last character is '\\', check that before calling.
1728 static int globhack(const char *src, int flags, glob_t *pglob)
1733 for (cnt=1, s=src; s && *s; s++) {
1734 if (*s == '\\') s++;
1738 if (!dest) return GLOB_NOSPACE;
1739 if (!(flags & GLOB_APPEND)) {
1740 pglob->gl_pathv=NULL;
1745 pathc = ++pglob->gl_pathc;
1746 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
1747 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
1748 pglob->gl_pathv[pathc-1]=dest;
1749 pglob->gl_pathv[pathc]=NULL;
1750 for (s=src; s && *s; s++, dest++) {
1751 if (*s == '\\') s++;
1758 /* XXX broken if the last character is '\\', check that before calling */
1759 static int glob_needed(const char *s)
1762 if (*s == '\\') s++;
1763 if (strchr("*[?",*s)) return 1;
1769 static void globprint(glob_t *pglob)
1772 debug_printf("glob_t at %p:\n", pglob);
1773 debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
1774 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
1775 for (i=0; i<pglob->gl_pathc; i++)
1776 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
1777 pglob->gl_pathv[i], pglob->gl_pathv[i]);
1781 static int xglob(o_string *dest, int flags, glob_t *pglob)
1785 /* short-circuit for null word */
1786 /* we can code this better when the debug_printf's are gone */
1787 if (dest->length == 0) {
1788 if (dest->nonnull) {
1789 /* bash man page calls this an "explicit" null */
1790 gr = globhack(dest->data, flags, pglob);
1791 debug_printf("globhack returned %d\n",gr);
1795 } else if (glob_needed(dest->data)) {
1796 gr = glob(dest->data, flags, NULL, pglob);
1797 debug_printf("glob returned %d\n",gr);
1798 if (gr == GLOB_NOMATCH) {
1799 /* quote removal, or more accurately, backslash removal */
1800 gr = globhack(dest->data, flags, pglob);
1801 debug_printf("globhack returned %d\n",gr);
1804 gr = globhack(dest->data, flags, pglob);
1805 debug_printf("globhack returned %d\n",gr);
1807 if (gr == GLOB_NOSPACE)
1808 bb_error_msg_and_die("out of memory during glob");
1809 if (gr != 0) { /* GLOB_ABORTED ? */
1810 bb_error_msg("glob(3) error %d",gr);
1812 /* globprint(glob_target); */
1816 /* This is used to get/check local shell variables */
1817 static char *get_local_var(const char *s)
1819 struct variables *cur;
1823 for (cur = top_vars; cur; cur=cur->next)
1824 if(strcmp(cur->name, s)==0)
1829 /* This is used to set local shell variables
1830 flg_export==0 if only local (not exporting) variable
1831 flg_export==1 if "new" exporting environ
1832 flg_export>1 if current startup environ (not call putenv()) */
1833 static int set_local_var(const char *s, int flg_export)
1837 struct variables *cur;
1841 /* Assume when we enter this function that we are already in
1842 * NAME=VALUE format. So the first order of business is to
1843 * split 's' on the '=' into 'name' and 'value' */
1844 value = strchr(name, '=');
1845 if (value==0 && ++value==0) {
1851 for(cur = top_vars; cur; cur = cur->next) {
1852 if(strcmp(cur->name, name)==0)
1857 if(strcmp(cur->value, value)==0) {
1858 if(flg_export>0 && cur->flg_export==0)
1859 cur->flg_export=flg_export;
1863 if(cur->flg_read_only) {
1864 bb_error_msg("%s: readonly variable", name);
1867 if(flg_export>0 || cur->flg_export>1)
1871 cur->value = strdup(value);
1875 cur = malloc(sizeof(struct variables));
1879 cur->name = strdup(name);
1880 if(cur->name == 0) {
1884 struct variables *bottom = top_vars;
1885 cur->value = strdup(value);
1887 cur->flg_export = flg_export;
1888 cur->flg_read_only = 0;
1889 while(bottom->next) bottom=bottom->next;
1895 if(result==0 && cur->flg_export==1) {
1897 result = putenv(name);
1900 if(result>0) /* equivalent to previous set */
1906 static void unset_local_var(const char *name)
1908 struct variables *cur;
1911 for (cur = top_vars; cur; cur=cur->next) {
1912 if(strcmp(cur->name, name)==0)
1916 struct variables *next = top_vars;
1917 if(cur->flg_read_only) {
1918 bb_error_msg("%s: readonly variable", name);
1922 unsetenv(cur->name);
1925 while (next->next != cur)
1927 next->next = cur->next;
1934 static int is_assignment(const char *s)
1936 if (s==NULL || !isalpha(*s)) return 0;
1938 while(isalnum(*s) || *s=='_') ++s;
1942 /* the src parameter allows us to peek forward to a possible &n syntax
1943 * for file descriptor duplication, e.g., "2>&1".
1944 * Return code is 0 normally, 1 if a syntax error is detected in src.
1945 * Resource errors (in xmalloc) cause the process to exit */
1946 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
1947 struct in_str *input)
1949 struct child_prog *child=ctx->child;
1950 struct redir_struct *redir = child->redirects;
1951 struct redir_struct *last_redir=NULL;
1953 /* Create a new redir_struct and drop it onto the end of the linked list */
1958 redir = xmalloc(sizeof(struct redir_struct));
1960 redir->word.gl_pathv=NULL;
1962 last_redir->next=redir;
1964 child->redirects=redir;
1968 redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
1970 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
1972 /* Check for a '2>&1' type redirect */
1973 redir->dup = redirect_dup_num(input);
1974 if (redir->dup == -2) return 1; /* syntax error */
1975 if (redir->dup != -1) {
1976 /* Erik had a check here that the file descriptor in question
1977 * is legit; I postpone that to "run time"
1978 * A "-" representation of "close me" shows up as a -3 here */
1979 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
1981 /* We do _not_ try to open the file that src points to,
1982 * since we need to return and let src be expanded first.
1983 * Set ctx->pending_redirect, so we know what to do at the
1984 * end of the next parsed word.
1986 ctx->pending_redirect = redir;
1991 static struct pipe *new_pipe(void) {
1993 pi = xmalloc(sizeof(struct pipe));
1997 pi->followup = 0; /* invalid */
1998 pi->r_mode = RES_NONE;
2002 static void initialize_context(struct p_context *ctx)
2005 ctx->pending_redirect=NULL;
2007 ctx->list_head=new_pipe();
2008 ctx->pipe=ctx->list_head;
2012 done_command(ctx); /* creates the memory for working child */
2015 /* normal return is 0
2016 * if a reserved word is found, and processed, return 1
2017 * should handle if, then, elif, else, fi, for, while, until, do, done.
2018 * case, function, and select are obnoxious, save those for later.
2020 static int reserved_word(o_string *dest, struct p_context *ctx)
2022 struct reserved_combo {
2027 /* Mostly a list of accepted follow-up reserved words.
2028 * FLAG_END means we are done with the sequence, and are ready
2029 * to turn the compound list into a command.
2030 * FLAG_START means the word must start a new compound list.
2032 static struct reserved_combo reserved_list[] = {
2033 { "if", RES_IF, FLAG_THEN | FLAG_START },
2034 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2035 { "elif", RES_ELIF, FLAG_THEN },
2036 { "else", RES_ELSE, FLAG_FI },
2037 { "fi", RES_FI, FLAG_END },
2038 { "for", RES_FOR, FLAG_IN | FLAG_START },
2039 { "while", RES_WHILE, FLAG_DO | FLAG_START },
2040 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
2041 { "in", RES_IN, FLAG_DO },
2042 { "do", RES_DO, FLAG_DONE },
2043 { "done", RES_DONE, FLAG_END }
2045 struct reserved_combo *r;
2046 for (r=reserved_list;
2047 #define NRES sizeof(reserved_list)/sizeof(struct reserved_combo)
2048 r<reserved_list+NRES; r++) {
2049 if (strcmp(dest->data, r->literal) == 0) {
2050 debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2051 if (r->flag & FLAG_START) {
2052 struct p_context *new = xmalloc(sizeof(struct p_context));
2053 debug_printf("push stack\n");
2054 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2061 *new = *ctx; /* physical copy */
2062 initialize_context(ctx);
2064 } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2071 ctx->old_flag = r->flag;
2072 if (ctx->old_flag & FLAG_END) {
2073 struct p_context *old;
2074 debug_printf("pop stack\n");
2075 done_pipe(ctx,PIPE_SEQ);
2077 old->child->group = ctx->list_head;
2078 old->child->subshell = 0;
2079 *ctx = *old; /* physical copy */
2089 /* normal return is 0.
2090 * Syntax or xglob errors return 1. */
2091 static int done_word(o_string *dest, struct p_context *ctx)
2093 struct child_prog *child=ctx->child;
2094 glob_t *glob_target;
2097 debug_printf("done_word: %s %p\n", dest->data, child);
2098 if (dest->length == 0 && !dest->nonnull) {
2099 debug_printf(" true null, ignored\n");
2102 if (ctx->pending_redirect) {
2103 glob_target = &ctx->pending_redirect->word;
2107 return 1; /* syntax error, groups and arglists don't mix */
2109 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2110 debug_printf("checking %s for reserved-ness\n",dest->data);
2111 if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2113 glob_target = &child->glob_result;
2114 if (child->argv) flags |= GLOB_APPEND;
2116 gr = xglob(dest, flags, glob_target);
2117 if (gr != 0) return 1;
2120 if (ctx->pending_redirect) {
2121 ctx->pending_redirect=NULL;
2122 if (glob_target->gl_pathc != 1) {
2123 bb_error_msg("ambiguous redirect");
2127 child->argv = glob_target->gl_pathv;
2129 if (ctx->w == RES_FOR) {
2130 done_word(dest,ctx);
2131 done_pipe(ctx,PIPE_SEQ);
2136 /* The only possible error here is out of memory, in which case
2138 static int done_command(struct p_context *ctx)
2140 /* The child is really already in the pipe structure, so
2141 * advance the pipe counter and make a new, null child.
2142 * Only real trickiness here is that the uncommitted
2143 * child structure, to which ctx->child points, is not
2144 * counted in pi->num_progs. */
2145 struct pipe *pi=ctx->pipe;
2146 struct child_prog *prog=ctx->child;
2148 if (prog && prog->group == NULL
2149 && prog->argv == NULL
2150 && prog->redirects == NULL) {
2151 debug_printf("done_command: skipping null command\n");
2155 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2157 debug_printf("done_command: initializing\n");
2159 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2161 prog = pi->progs + pi->num_progs;
2162 prog->redirects = NULL;
2164 prog->is_stopped = 0;
2166 prog->glob_result.gl_pathv = NULL;
2170 prog->type = ctx->type;
2172 /* but ctx->pipe and ctx->list_head remain unchanged */
2176 static int done_pipe(struct p_context *ctx, pipe_style type)
2179 done_command(ctx); /* implicit closure of previous command */
2180 debug_printf("done_pipe, type %d\n", type);
2181 ctx->pipe->followup = type;
2182 ctx->pipe->r_mode = ctx->w;
2184 ctx->pipe->next = new_p;
2187 done_command(ctx); /* set up new pipe to accept commands */
2191 /* peek ahead in the in_str to find out if we have a "&n" construct,
2192 * as in "2>&1", that represents duplicating a file descriptor.
2193 * returns either -2 (syntax error), -1 (no &), or the number found.
2195 static int redirect_dup_num(struct in_str *input)
2199 if (ch != '&') return -1;
2201 b_getch(input); /* get the & */
2205 return -3; /* "-" represents "close me" */
2207 while (isdigit(ch)) {
2215 bb_error_msg("ambiguous redirect");
2219 /* If a redirect is immediately preceded by a number, that number is
2220 * supposed to tell which file descriptor to redirect. This routine
2221 * looks for such preceding numbers. In an ideal world this routine
2222 * needs to handle all the following classes of redirects...
2223 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2224 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2225 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2226 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2227 * A -1 output from this program means no valid number was found, so the
2228 * caller should use the appropriate default for this redirection.
2230 static int redirect_opt_num(o_string *o)
2234 if (o->length==0) return -1;
2235 for(num=0; num<o->length; num++) {
2236 if (!isdigit(*(o->data+num))) {
2240 /* reuse num (and save an int) */
2246 static FILE *generate_stream_from_list(struct pipe *head)
2250 int pid, channel[2];
2251 if (pipe(channel)<0) bb_perror_msg_and_die("pipe");
2252 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
2258 bb_perror_msg_and_die("fork");
2259 } else if (pid==0) {
2261 if (channel[1] != 1) {
2266 #define SURROGATE "surrogate response"
2267 write(1,SURROGATE,sizeof(SURROGATE));
2268 _exit(run_list(head));
2270 _exit(run_list_real(head)); /* leaks memory */
2273 debug_printf("forked child %d\n",pid);
2275 pf = fdopen(channel[0],"r");
2276 debug_printf("pipe on FILE *%p\n",pf);
2278 free_pipe_list(head,0);
2279 pf=popen("echo surrogate response","r");
2280 debug_printf("started fake pipe on FILE *%p\n",pf);
2285 /* this version hacked for testing purposes */
2286 /* return code is exit status of the process that is run. */
2287 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2290 o_string result=NULL_O_STRING;
2291 struct p_context inner;
2293 struct in_str pipe_str;
2294 initialize_context(&inner);
2296 /* recursion to generate command */
2297 retcode = parse_stream(&result, &inner, input, subst_end);
2298 if (retcode != 0) return retcode; /* syntax error or EOF */
2299 done_word(&result, &inner);
2300 done_pipe(&inner, PIPE_SEQ);
2303 p=generate_stream_from_list(inner.list_head);
2304 if (p==NULL) return 1;
2305 mark_open(fileno(p));
2306 setup_file_in_str(&pipe_str, p);
2308 /* now send results of command back into original context */
2309 retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2310 /* XXX In case of a syntax error, should we try to kill the child?
2311 * That would be tough to do right, so just read until EOF. */
2313 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2316 debug_printf("done reading from pipe, pclose()ing\n");
2317 /* This is the step that wait()s for the child. Should be pretty
2318 * safe, since we just read an EOF from its stdout. We could try
2319 * to better, by using wait(), and keeping track of background jobs
2320 * at the same time. That would be a lot of work, and contrary
2321 * to the KISS philosophy of this program. */
2322 mark_closed(fileno(p));
2324 free_pipe_list(inner.list_head,0);
2325 debug_printf("pclosed, retcode=%d\n",retcode);
2326 /* XXX this process fails to trim a single trailing newline */
2330 static int parse_group(o_string *dest, struct p_context *ctx,
2331 struct in_str *input, int ch)
2334 struct p_context sub;
2335 struct child_prog *child = ctx->child;
2338 return 1; /* syntax error, groups and arglists don't mix */
2340 initialize_context(&sub);
2342 case '(': endch=')'; child->subshell=1; break;
2343 case '{': endch='}'; break;
2344 default: syntax(); /* really logic error */
2346 rcode=parse_stream(dest,&sub,input,endch);
2347 done_word(dest,&sub); /* finish off the final word in the subcontext */
2348 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2349 child->group = sub.list_head;
2351 /* child remains "open", available for possible redirects */
2354 /* basically useful version until someone wants to get fancier,
2355 * see the bash man page under "Parameter Expansion" */
2356 static char *lookup_param(char *src)
2362 p = get_local_var(src);
2367 /* return code: 0 for OK, 1 for syntax error */
2368 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2372 int ch = input->peek(input); /* first character after the $ */
2373 debug_printf("handle_dollar: ch=%c\n",ch);
2375 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2377 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2381 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2382 } else if (isdigit(ch)) {
2383 i = ch-'0'; /* XXX is $0 special? */
2384 if (i<global_argc) {
2385 parse_string(dest, ctx, global_argv[i]); /* recursion */
2388 } else switch (ch) {
2390 b_adduint(dest,getpid());
2394 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2398 b_adduint(dest,last_return_code);
2402 b_adduint(dest,global_argc ? global_argc-1 : 0);
2406 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2409 /* XXX maybe someone will try to escape the '}' */
2410 while(ch=b_getch(input),ch!=EOF && ch!='}') {
2417 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2421 process_command_subs(dest, ctx, input, ')');
2425 for (i=1; i<global_argc; i++) {
2426 parse_string(dest, ctx, global_argv[i]);
2427 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2433 /* still unhandled, but should be eventually */
2434 bb_error_msg("unhandled syntax: $%c",ch);
2438 b_addqchr(dest,'$',dest->quote);
2440 /* Eat the character if the flag was set. If the compiler
2441 * is smart enough, we could substitute "b_getch(input);"
2442 * for all the "advance = 1;" above, and also end up with
2443 * a nice size-optimized program. Hah! That'll be the day.
2445 if (advance) b_getch(input);
2449 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2452 setup_string_in_str(&foo, src);
2453 return parse_stream(dest, ctx, &foo, '\0');
2456 /* return code is 0 for normal exit, 1 for syntax error */
2457 int parse_stream(o_string *dest, struct p_context *ctx,
2458 struct in_str *input, int end_trigger)
2462 redir_type redir_style;
2465 /* Only double-quote state is handled in the state variable dest->quote.
2466 * A single-quote triggers a bypass of the main loop until its mate is
2467 * found. When recursing, quote state is passed in via dest->quote. */
2469 debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2470 while ((ch=b_getch(input))!=EOF) {
2472 next = (ch == '\n') ? 0 : b_peek(input);
2473 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
2474 ch,ch,m,dest->quote);
2475 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2476 b_addqchr(dest, ch, dest->quote);
2478 if (m==2) { /* unquoted IFS */
2479 if (done_word(dest, ctx)) {
2482 /* If we aren't performing a substitution, treat a newline as a
2483 * command separator. */
2484 if (end_trigger != '\0' && ch=='\n')
2485 done_pipe(ctx,PIPE_SEQ);
2487 if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2488 debug_printf("leaving parse_stream (triggered)\n");
2493 /* Yahoo! Time to run with it! */
2494 done_pipe(ctx,PIPE_SEQ);
2495 run_list(ctx->list_head);
2496 initialize_context(ctx);
2499 if (m!=2) switch (ch) {
2501 if (dest->length == 0 && !dest->quote) {
2502 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2504 b_addqchr(dest, ch, dest->quote);
2512 b_addqchr(dest, '\\', dest->quote);
2513 b_addqchr(dest, b_getch(input), dest->quote);
2516 if (handle_dollar(dest, ctx, input)!=0) return 1;
2520 while(ch=b_getch(input),ch!=EOF && ch!='\'') {
2530 dest->quote = !dest->quote;
2533 process_command_subs(dest, ctx, input, '`');
2536 redir_fd = redirect_opt_num(dest);
2537 done_word(dest, ctx);
2538 redir_style=REDIRECT_OVERWRITE;
2540 redir_style=REDIRECT_APPEND;
2542 } else if (next == '(') {
2543 syntax(); /* until we support >(list) Process Substitution */
2546 setup_redirect(ctx, redir_fd, redir_style, input);
2549 redir_fd = redirect_opt_num(dest);
2550 done_word(dest, ctx);
2551 redir_style=REDIRECT_INPUT;
2553 redir_style=REDIRECT_HEREIS;
2555 } else if (next == '>') {
2556 redir_style=REDIRECT_IO;
2558 } else if (next == '(') {
2559 syntax(); /* until we support <(list) Process Substitution */
2562 setup_redirect(ctx, redir_fd, redir_style, input);
2565 done_word(dest, ctx);
2566 done_pipe(ctx,PIPE_SEQ);
2569 done_word(dest, ctx);
2572 done_pipe(ctx,PIPE_AND);
2574 done_pipe(ctx,PIPE_BG);
2578 done_word(dest, ctx);
2581 done_pipe(ctx,PIPE_OR);
2583 /* we could pick up a file descriptor choice here
2584 * with redirect_opt_num(), but bash doesn't do it.
2585 * "echo foo 2| cat" yields "foo 2". */
2591 if (parse_group(dest, ctx, input, ch)!=0) return 1;
2595 syntax(); /* Proper use of this character caught by end_trigger */
2599 syntax(); /* this is really an internal logic error */
2604 /* complain if quote? No, maybe we just finished a command substitution
2605 * that was quoted. Example:
2606 * $ echo "`cat foo` plus more"
2607 * and we just got the EOF generated by the subshell that ran "cat foo"
2608 * The only real complaint is if we got an EOF when end_trigger != '\0',
2609 * that is, we were really supposed to get end_trigger, and never got
2610 * one before the EOF. Can't use the standard "syntax error" return code,
2611 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
2612 debug_printf("leaving parse_stream (EOF)\n");
2613 if (end_trigger != '\0') return -1;
2617 static void mapset(const char *set, int code)
2619 const unsigned char *s;
2620 for (s = (const unsigned char *)set; *s; s++) map[(int)*s] = code;
2623 static void update_ifs_map(void)
2625 /* char *ifs and char map[256] are both globals. */
2626 ifs = getenv("IFS");
2627 if (ifs == NULL) ifs=" \t\n";
2628 /* Precompute a list of 'flow through' behavior so it can be treated
2629 * quickly up front. Computation is necessary because of IFS.
2630 * Special case handling of IFS == " \t\n" is not implemented.
2631 * The map[] array only really needs two bits each, and on most machines
2632 * that would be faster because of the reduced L1 cache footprint.
2634 memset(map,0,sizeof(map)); /* most characters flow through always */
2635 mapset("\\$'\"`", 3); /* never flow through */
2636 mapset("<>;&|(){}#", 1); /* flow through if quoted */
2637 mapset(ifs, 2); /* also flow through if quoted */
2640 /* most recursion does not come through here, the exception is
2641 * from builtin_source() */
2642 int parse_stream_outer(struct in_str *inp, int flag)
2645 struct p_context ctx;
2646 o_string temp=NULL_O_STRING;
2650 initialize_context(&ctx);
2652 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
2654 rcode = parse_stream(&temp, &ctx, inp, '\n');
2655 if (rcode != 1 && ctx.old_flag != 0) {
2658 if (rcode != 1 && ctx.old_flag == 0) {
2659 done_word(&temp, &ctx);
2660 done_pipe(&ctx,PIPE_SEQ);
2661 run_list(ctx.list_head);
2663 if (ctx.old_flag != 0) {
2670 free_pipe_list(ctx.list_head,0);
2673 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
2677 static int parse_string_outer(const char *s, int flag)
2679 struct in_str input;
2680 setup_string_in_str(&input, s);
2681 return parse_stream_outer(&input, flag);
2684 static int parse_file_outer(FILE *f)
2687 struct in_str input;
2688 setup_file_in_str(&input, f);
2689 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
2693 /* Make sure we have a controlling tty. If we get started under a job
2694 * aware app (like bash for example), make sure we are now in charge so
2695 * we don't fight over who gets the foreground */
2696 static void setup_job_control(void)
2698 static pid_t shell_pgrp;
2699 /* Loop until we are in the foreground. */
2700 while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
2701 kill (- shell_pgrp, SIGTTIN);
2703 /* Ignore interactive and job-control signals. */
2704 signal(SIGINT, SIG_IGN);
2705 signal(SIGQUIT, SIG_IGN);
2706 signal(SIGTERM, SIG_IGN);
2707 signal(SIGTSTP, SIG_IGN);
2708 signal(SIGTTIN, SIG_IGN);
2709 signal(SIGTTOU, SIG_IGN);
2710 signal(SIGCHLD, SIG_IGN);
2712 /* Put ourselves in our own process group. */
2714 shell_pgrp = getpid ();
2715 setpgid (shell_pgrp, shell_pgrp);
2717 /* Grab control of the terminal. */
2718 tcsetpgrp(shell_terminal, shell_pgrp);
2721 int hush_main(int argc, char **argv)
2727 /* XXX what should these be while sourcing /etc/profile? */
2731 /* (re?) initialize globals. Sometimes hush_main() ends up calling
2732 * hush_main(), therefore we cannot rely on the BSS to zero out this
2733 * stuff. Reset these to 0 every time. */
2735 /* map[] is taken care of with call to update_ifs_map() */
2738 close_me_head = NULL;
2743 /* Initialize some more globals to non-zero values */
2745 #ifdef CONFIG_FEATURE_COMMAND_EDITING
2746 cmdedit_set_initial_prompt();
2752 /* initialize our shell local variables with the values
2753 * currently living in the environment */
2756 set_local_var(*e, 2); /* without call putenv() */
2759 last_return_code=EXIT_SUCCESS;
2762 if (argv[0] && argv[0][0] == '-') {
2763 debug_printf("\nsourcing /etc/profile\n");
2764 if ((input = fopen("/etc/profile", "r")) != NULL) {
2765 mark_open(fileno(input));
2766 parse_file_outer(input);
2767 mark_closed(fileno(input));
2773 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
2777 global_argv = argv+optind;
2778 global_argc = argc-optind;
2779 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
2791 fprintf(stderr, "Usage: sh [FILE]...\n"
2792 " or: sh -c command [args]...\n\n");
2799 /* A shell is interactive if the `-i' flag was given, or if all of
2800 * the following conditions are met:
2802 * no arguments remaining or the -s flag given
2803 * standard input is a terminal
2804 * standard output is a terminal
2805 * Refer to Posix.2, the description of the `sh' utility. */
2806 if (argv[optind]==NULL && input==stdin &&
2807 isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
2811 debug_printf("\ninteractive=%d\n", interactive);
2813 /* Looks like they want an interactive shell */
2814 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
2815 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
2816 printf( "Enter 'help' for a list of built-in commands.\n\n");
2818 setup_job_control();
2821 if (argv[optind]==NULL) {
2822 opt=parse_file_outer(stdin);
2826 debug_printf("\nrunning script '%s'\n", argv[optind]);
2827 global_argv = argv+optind;
2828 global_argc = argc-optind;
2829 input = bb_xfopen(argv[optind], "r");
2830 opt = parse_file_outer(input);
2832 #ifdef CONFIG_FEATURE_CLEAN_UP
2834 if (cwd && cwd != bb_msg_unknown)
2837 struct variables *cur, *tmp;
2838 for(cur = top_vars; cur; cur = tmp) {
2840 if (!cur->flg_read_only) {
2850 return(opt?opt:last_return_code);
2853 static char *insert_var_value(char *inp)
2855 int res_str_len = 0;
2858 char *p, *p1, *res_str = NULL;
2860 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
2863 res_str = xrealloc(res_str, (res_str_len + len));
2864 strncpy((res_str + res_str_len), inp, len);
2868 p = strchr(inp, SPECIAL_VAR_SYMBOL);
2870 if ((p1 = lookup_param(inp))) {
2871 len = res_str_len + strlen(p1);
2872 res_str = xrealloc(res_str, (1 + len));
2873 strcpy((res_str + res_str_len), p1);
2876 *p = SPECIAL_VAR_SYMBOL;
2881 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
2882 strcpy((res_str + res_str_len), inp);
2883 while ((p = strchr(res_str, '\n'))) {
2887 return (res_str == NULL) ? inp : res_str;
2890 static char **make_list_in(char **inp, char *name)
2893 int name_len = strlen(name);
2898 /* create list of variable values */
2899 list = xmalloc(sizeof(*list));
2900 for (i = 0; inp[i]; i++) {
2901 p3 = insert_var_value(inp[i]);
2908 if ((p2 = strchr(p1, ' '))) {
2914 /* we use n + 2 in realloc for list,because we add
2915 * new element and then we will add NULL element */
2916 list = xrealloc(list, sizeof(*list) * (n + 2));
2917 list[n] = xmalloc(2 + name_len + len);
2918 strcpy(list[n], name);
2919 strcat(list[n], "=");
2920 strncat(list[n], p1, len);
2921 list[n++][name_len + len + 1] = '\0';
2924 if (p3 != inp[i]) free(p3);
2930 /* Make new string for parser */
2931 static char * make_string(char ** inp)
2938 for (n = 0; inp[n]; n++) {
2939 p = insert_var_value(inp[n]);
2940 str = xrealloc(str, (len + strlen(p)));
2947 len = strlen(str) + 3;
2948 if (p != inp[n]) free(p);
2951 *(str + len) = '\n';
2952 *(str + len + 1) = '\0';