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 * b_addchr() derived from similar w_addchar function in glibc-2.2
24 * setup_redirect(), redirect_opt_num(), and big chunks of main()
25 * and many builtins derived from contributions by Erik Andersen
26 * miscellaneous bugfixes from Matt Kraai
28 * There are two big (and related) architecture differences between
29 * this parser and the lash parser. One is that this version is
30 * actually designed from the ground up to understand nearly all
31 * of the Bourne grammar. The second, consequential change is that
32 * the parser and input reader have been turned inside out. Now,
33 * the parser is in control, and asks for input as needed. The old
34 * way had the input reader in control, and it asked for parsing to
35 * take place as needed. The new way makes it much easier to properly
36 * handle the recursion implicit in the various substitutions, especially
37 * across continuation lines.
39 * Bash grammar not implemented: (how many of these were in original sh?)
40 * $@ (those sure look like weird quoting rules)
42 * ! negation operator for pipes
43 * &> and >& redirection of stdout+stderr
46 * fancy forms of Parameter Expansion
48 * Arithmetic Expansion
49 * <(list) and >(list) Process Substitution
50 * reserved words: case, esac, select, function
51 * Here Documents ( << word )
54 * job handling woefully incomplete and buggy
55 * reserved word execution woefully incomplete and buggy
57 * port selected bugfixes from post-0.49 busybox lash - done?
58 * finish implementing reserved words: for, while, until, do, done
59 * change { and } from special chars to reserved words
60 * builtins: break, continue, eval, return, set, trap, ulimit
62 * handle children going into background
63 * clean up recognition of null pipes
64 * check setting of global_argc and global_argv
65 * control-C handling, probably with longjmp
66 * follow IFS rules more precisely, including update semantics
67 * figure out what to do with backslash-newline
68 * explain why we use signal instead of sigaction
69 * propagate syntax errors, die on resource errors?
70 * continuation lines, both explicit and implicit - done?
71 * memory leak finding and plugging - done?
72 * more testing, especially quoting rules and redirection
73 * document how quoting rules not precisely followed for variable assignments
74 * maybe change map[] to use 2-bit entries
75 * (eventually) remove all the printf's
77 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
81 #include <glob.h> /* glob, of course */
82 #include <getopt.h> /* should be pretty obvious */
84 //#include <sys/wait.h>
87 /* #include <dmalloc.h> */
88 /* #define DEBUG_SHELL */
91 #define SPECIAL_VAR_SYMBOL 03
92 #define FLAG_EXIT_FROM_LOOP 1
93 #define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
94 #define FLAG_REPARSING (1 << 2) /* >=2nd pass */
98 REDIRECT_OVERWRITE = 2,
104 /* The descrip member of this structure is only used to make debugging
106 static const struct {
112 { O_RDONLY, 0, "<" },
113 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
114 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
115 { O_RDONLY, -1, "<<" },
126 /* might eventually control execution */
143 #define FLAG_END (1<<RES_NONE)
144 #define FLAG_IF (1<<RES_IF)
145 #define FLAG_THEN (1<<RES_THEN)
146 #define FLAG_ELIF (1<<RES_ELIF)
147 #define FLAG_ELSE (1<<RES_ELSE)
148 #define FLAG_FI (1<<RES_FI)
149 #define FLAG_FOR (1<<RES_FOR)
150 #define FLAG_WHILE (1<<RES_WHILE)
151 #define FLAG_UNTIL (1<<RES_UNTIL)
152 #define FLAG_DO (1<<RES_DO)
153 #define FLAG_DONE (1<<RES_DONE)
154 #define FLAG_IN (1<<RES_IN)
155 #define FLAG_START (1<<RES_XXXX)
157 /* This holds pointers to the various results of parsing */
159 struct child_prog *child;
160 struct pipe *list_head;
162 struct redir_struct *pending_redirect;
164 int old_flag; /* for figuring out valid reserved words */
165 struct p_context *stack;
166 int type; /* define type of parser : ";$" common or special symbol */
167 /* How about quoting status? */
170 struct redir_struct {
171 redir_type type; /* type of redirection */
172 int fd; /* file descriptor being redirected */
173 int dup; /* -1, or file descriptor being duplicated */
174 struct redir_struct *next; /* pointer to the next redirect in the list */
175 glob_t word; /* *word.gl_pathv is the filename */
179 pid_t pid; /* 0 if exited */
180 char **argv; /* program name and arguments */
181 struct pipe *group; /* if non-NULL, first in group or subshell */
182 int subshell; /* flag, non-zero if group must be forked */
183 struct redir_struct *redirects; /* I/O redirections */
184 glob_t glob_result; /* result of parameter globbing */
185 int is_stopped; /* is the program currently running? */
186 struct pipe *family; /* pointer back to the child's parent pipe */
187 int sp; /* number of SPECIAL_VAR_SYMBOL */
192 int jobid; /* job number */
193 int num_progs; /* total number of programs in job */
194 int running_progs; /* number of programs running */
195 char *text; /* name of job */
196 char *cmdbuf; /* buffer various argv's point into */
197 pid_t pgrp; /* process group ID for the job */
198 struct child_prog *progs; /* array of commands in pipe */
199 struct pipe *next; /* to track background commands */
200 int stopped_progs; /* number of programs alive, but stopped */
201 int job_context; /* bitmask defining current context */
202 pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
203 reserved_style r_mode; /* supports if, for, while, until */
208 struct close_me *next;
216 struct variables *next;
219 /* globals, connect us to the outside world
220 * the first three support $?, $#, and $1 */
221 static char **global_argv;
222 static int global_argc;
223 static int last_return_code;
224 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
226 /* "globals" within this file */
227 static const char *ifs;
228 static unsigned char map[256];
229 static int fake_mode;
230 static int interactive;
231 static struct close_me *close_me_head;
232 static const char *cwd;
233 static struct pipe *job_list;
234 static unsigned last_bg_pid;
235 static int last_jobid;
236 static unsigned shell_terminal;
237 static const char *PS1;
238 static const char *PS2;
239 static struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
240 static struct variables *top_vars = &shell_ver;
243 #define B_CHUNK (100)
253 #define NULL_O_STRING {NULL,0,0,0,0}
254 /* used for initialization:
255 o_string foo = NULL_O_STRING; */
257 /* I can almost use ordinary FILE *. Is open_memstream() universally
258 * available? Where is it documented? */
265 int (*get) (struct in_str *);
266 int (*peek) (struct in_str *);
268 #define b_getch(input) ((input)->get(input))
269 #define b_peek(input) ((input)->peek(input))
271 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
273 struct built_in_command {
274 const char *cmd; /* name */
275 const char *descr; /* description */
276 int (*function) (struct child_prog *); /* function ptr */
279 /* belongs in busybox.h */
280 static int max(int a, int b)
282 return (a > b) ? a : b;
285 /* This should be in utility.c */
287 static void debug_printf(const char *format, ...)
290 va_start(args, format);
291 vfprintf(stderr, format, args);
294 /* broken, of course, but OK for testing */
295 static char *indenter(int i)
297 static char blanks[] = " ";
298 return &blanks[sizeof(blanks)-i-1];
301 #define debug_printf(...) do {} while (0)
303 #define final_printf debug_printf
305 static void __syntax(const char *file, int line)
307 bb_error_msg("syntax error %s:%d", file, line);
309 // NB: was __FILE__, but that produces full path sometimess, so...
310 #define syntax() __syntax("hush.c", __LINE__)
312 /* Index of subroutines: */
313 /* function prototypes for builtins */
314 static int builtin_cd(struct child_prog *child);
315 static int builtin_env(struct child_prog *child);
316 static int builtin_eval(struct child_prog *child);
317 static int builtin_exec(struct child_prog *child);
318 static int builtin_exit(struct child_prog *child);
319 static int builtin_export(struct child_prog *child);
320 static int builtin_fg_bg(struct child_prog *child);
321 static int builtin_help(struct child_prog *child);
322 static int builtin_jobs(struct child_prog *child);
323 static int builtin_pwd(struct child_prog *child);
324 static int builtin_read(struct child_prog *child);
325 static int builtin_set(struct child_prog *child);
326 static int builtin_shift(struct child_prog *child);
327 static int builtin_source(struct child_prog *child);
328 static int builtin_umask(struct child_prog *child);
329 static int builtin_unset(struct child_prog *child);
330 static int builtin_not_written(struct child_prog *child);
331 /* o_string manipulation: */
332 static int b_check_space(o_string *o, int len);
333 static int b_addchr(o_string *o, int ch);
334 static void b_reset(o_string *o);
335 static int b_addqchr(o_string *o, int ch, int quote);
336 static int b_adduint(o_string *o, unsigned i);
337 /* in_str manipulations: */
338 static int static_get(struct in_str *i);
339 static int static_peek(struct in_str *i);
340 static int file_get(struct in_str *i);
341 static int file_peek(struct in_str *i);
342 static void setup_file_in_str(struct in_str *i, FILE *f);
343 static void setup_string_in_str(struct in_str *i, const char *s);
344 /* close_me manipulations: */
345 static void mark_open(int fd);
346 static void mark_closed(int fd);
347 static void close_all(void);
348 /* "run" the final data structures: */
349 static int free_pipe_list(struct pipe *head, int indent);
350 static int free_pipe(struct pipe *pi, int indent);
351 /* really run the final data structures: */
352 static int setup_redirects(struct child_prog *prog, int squirrel[]);
353 static int run_list_real(struct pipe *pi);
354 static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN;
355 static int run_pipe_real(struct pipe *pi);
356 /* extended glob support: */
357 static int globhack(const char *src, int flags, glob_t *pglob);
358 static int glob_needed(const char *s);
359 static int xglob(o_string *dest, int flags, glob_t *pglob);
360 /* variable assignment: */
361 static int is_assignment(const char *s);
362 /* data structure manipulation: */
363 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
364 static void initialize_context(struct p_context *ctx);
365 static int done_word(o_string *dest, struct p_context *ctx);
366 static int done_command(struct p_context *ctx);
367 static int done_pipe(struct p_context *ctx, pipe_style type);
368 /* primary string parsing: */
369 static int redirect_dup_num(struct in_str *input);
370 static int redirect_opt_num(o_string *o);
371 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
372 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
373 static const char *lookup_param(const char *src);
374 static char *make_string(char **inp);
375 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
376 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
377 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
379 static int parse_stream_outer(struct in_str *inp, int flag);
380 static int parse_string_outer(const char *s, int flag);
381 static int parse_file_outer(FILE *f);
382 /* job management: */
383 static int checkjobs(struct pipe* fg_pipe);
384 static void insert_bg_job(struct pipe *pi);
385 static void remove_bg_job(struct pipe *pi);
386 /* local variable support */
387 static char **make_list_in(char **inp, char *name);
388 static char *insert_var_value(char *inp);
389 static const char *get_local_var(const char *var);
390 static void unset_local_var(const char *name);
391 static int set_local_var(const char *s, int flg_export);
393 /* Table of built-in functions. They can be forked or not, depending on
394 * context: within pipes, they fork. As simple commands, they do not.
395 * When used in non-forking context, they can change global variables
396 * in the parent shell process. If forked, of course they cannot.
397 * For example, 'unset foo | whatever' will parse and run, but foo will
398 * still be set at the end. */
399 static const struct built_in_command bltins[] = {
400 { "bg", "Resume a job in the background", builtin_fg_bg },
401 { "break", "Exit for, while or until loop", builtin_not_written },
402 { "cd", "Change working directory", builtin_cd },
403 { "continue", "Continue for, while or until loop", builtin_not_written },
404 { "env", "Print all environment variables", builtin_env },
405 { "eval", "Construct and run shell command", builtin_eval },
406 { "exec", "Exec command, replacing this shell with the exec'd process",
408 { "exit", "Exit from shell()", builtin_exit },
409 { "export", "Set environment variable", builtin_export },
410 { "fg", "Bring job into the foreground", builtin_fg_bg },
411 { "jobs", "Lists the active jobs", builtin_jobs },
412 { "pwd", "Print current directory", builtin_pwd },
413 { "read", "Input environment variable", builtin_read },
414 { "return", "Return from a function", builtin_not_written },
415 { "set", "Set/unset shell local variables", builtin_set },
416 { "shift", "Shift positional parameters", builtin_shift },
417 { "trap", "Trap signals", builtin_not_written },
418 { "ulimit","Controls resource limits", builtin_not_written },
419 { "umask","Sets file creation mask", builtin_umask },
420 { "unset", "Unset environment variable", builtin_unset },
421 { ".", "Source-in and run commands in a file", builtin_source },
422 { "help", "List shell built-in commands", builtin_help },
426 static const char *set_cwd(void)
428 if (cwd == bb_msg_unknown)
429 cwd = NULL; /* xrealloc_getcwd_or_warn(arg) calls free(arg)! */
430 cwd = xrealloc_getcwd_or_warn((char *)cwd);
432 cwd = bb_msg_unknown;
436 /* built-in 'eval' handler */
437 static int builtin_eval(struct child_prog *child)
440 int rcode = EXIT_SUCCESS;
442 if (child->argv[1]) {
443 str = make_string(child->argv + 1);
444 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
445 FLAG_PARSE_SEMICOLON);
447 rcode = last_return_code;
452 /* built-in 'cd <path>' handler */
453 static int builtin_cd(struct child_prog *child)
456 if (child->argv[1] == NULL)
457 newdir = getenv("HOME");
459 newdir = child->argv[1];
461 printf("cd: %s: %s\n", newdir, strerror(errno));
468 /* built-in 'env' handler */
469 static int builtin_env(struct child_prog *dummy ATTRIBUTE_UNUSED)
480 /* built-in 'exec' handler */
481 static int builtin_exec(struct child_prog *child)
483 if (child->argv[1] == NULL)
484 return EXIT_SUCCESS; /* Really? */
490 /* built-in 'exit' handler */
491 static int builtin_exit(struct child_prog *child)
493 if (child->argv[1] == NULL)
494 exit(last_return_code);
495 exit(atoi(child->argv[1]));
498 /* built-in 'export VAR=value' handler */
499 static int builtin_export(struct child_prog *child)
502 char *name = child->argv[1];
505 return builtin_env(child);
511 const char *value = strchr(name, '=');
515 /* They are exporting something without an =VALUE */
517 value = get_local_var(name);
519 size_t ln = strlen(name);
521 tmp = realloc(name, ln+strlen(value)+2);
525 sprintf(tmp+ln, "=%s", value);
529 /* bash does not return an error when trying to export
530 * an undefined variable. Do likewise. */
536 bb_perror_msg("export");
538 res = set_local_var(name, 1);
545 /* built-in 'fg' and 'bg' handler */
546 static int builtin_fg_bg(struct child_prog *child)
553 /* If they gave us no args, assume they want the last backgrounded task */
554 if (!child->argv[1]) {
555 for (pi = job_list; pi; pi = pi->next) {
556 if (pi->jobid == last_jobid) {
560 bb_error_msg("%s: no current job", child->argv[0]);
563 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
564 bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
567 for (pi = job_list; pi; pi = pi->next) {
568 if (pi->jobid == jobnum) {
572 bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
575 if (*child->argv[0] == 'f') {
576 /* Put the job into the foreground. */
577 tcsetpgrp(shell_terminal, pi->pgrp);
580 /* Restart the processes in the job */
581 for (i = 0; i < pi->num_progs; i++)
582 pi->progs[i].is_stopped = 0;
584 i = kill(- pi->pgrp, SIGCONT);
586 if (errno == ESRCH) {
589 bb_perror_msg("kill (SIGCONT)");
593 pi->stopped_progs = 0;
597 /* built-in 'help' handler */
598 static int builtin_help(struct child_prog *dummy ATTRIBUTE_UNUSED)
600 const struct built_in_command *x;
602 printf("\nBuilt-in commands:\n");
603 printf("-------------------\n");
604 for (x = bltins; x->cmd; x++) {
605 if (x->descr == NULL)
607 printf("%s\t%s\n", x->cmd, x->descr);
613 /* built-in 'jobs' handler */
614 static int builtin_jobs(struct child_prog *child ATTRIBUTE_UNUSED)
617 const char *status_string;
619 for (job = job_list; job; job = job->next) {
620 if (job->running_progs == job->stopped_progs)
621 status_string = "Stopped";
623 status_string = "Running";
625 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
630 /* built-in 'pwd' handler */
631 static int builtin_pwd(struct child_prog *dummy ATTRIBUTE_UNUSED)
637 /* built-in 'read VAR' handler */
638 static int builtin_read(struct child_prog *child)
642 if (child->argv[1]) {
646 string[0] = '\0'; /* In case stdin has only EOF */
648 fgets(string, sizeof(string), stdin);
650 var = malloc(strlen(child->argv[1]) + strlen(string) + 2);
652 sprintf(var, "%s=%s", child->argv[1], string);
653 res = set_local_var(var, 0);
657 bb_perror_msg("read");
658 free(var); /* So not move up to avoid breaking errno */
661 do res = getchar(); while (res != '\n' && res != EOF);
665 /* built-in 'set VAR=value' handler */
666 static int builtin_set(struct child_prog *child)
668 char *temp = child->argv[1];
672 for (e = top_vars; e; e = e->next)
673 printf("%s=%s\n", e->name, e->value);
675 set_local_var(temp, 0);
681 /* Built-in 'shift' handler */
682 static int builtin_shift(struct child_prog *child)
685 if (child->argv[1]) {
686 n = atoi(child->argv[1]);
688 if (n >= 0 && n < global_argc) {
689 /* XXX This probably breaks $0 */
697 /* Built-in '.' handler (read-in and execute commands from file) */
698 static int builtin_source(struct child_prog *child)
703 if (child->argv[1] == NULL)
706 /* XXX search through $PATH is missing */
707 input = fopen(child->argv[1], "r");
709 bb_error_msg("cannot open '%s'", child->argv[1]);
713 /* Now run the file */
714 /* XXX argv and argc are broken; need to save old global_argv
715 * (pointer only is OK!) on this stack frame,
716 * set global_argv=child->argv+1, recurse, and restore. */
717 mark_open(fileno(input));
718 status = parse_file_outer(input);
719 mark_closed(fileno(input));
724 static int builtin_umask(struct child_prog *child)
727 const char *arg = child->argv[1];
730 new_umask = strtoul(arg, &end, 8);
731 if (*end != '\0' || end == arg) {
735 new_umask = umask(0);
736 printf("%.3o\n", (unsigned) new_umask);
742 /* built-in 'unset VAR' handler */
743 static int builtin_unset(struct child_prog *child)
745 /* bash returned already true */
746 unset_local_var(child->argv[1]);
750 static int builtin_not_written(struct child_prog *child)
752 printf("builtin_%s not written\n", child->argv[0]);
756 static int b_check_space(o_string *o, int len)
758 /* It would be easy to drop a more restrictive policy
759 * in here, such as setting a maximum string length */
760 if (o->length + len > o->maxlen) {
761 char *old_data = o->data;
762 /* assert(data == NULL || o->maxlen != 0); */
763 o->maxlen += max(2*len, B_CHUNK);
764 o->data = realloc(o->data, 1 + o->maxlen);
765 if (o->data == NULL) {
769 return o->data == NULL;
772 static int b_addchr(o_string *o, int ch)
774 debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
775 if (b_check_space(o, 1))
777 o->data[o->length] = ch;
779 o->data[o->length] = '\0';
783 static void b_reset(o_string *o)
791 static void b_free(o_string *o)
799 /* My analysis of quoting semantics tells me that state information
800 * is associated with a destination, not a source.
802 static int b_addqchr(o_string *o, int ch, int quote)
804 if (quote && strchr("*?[\\", ch)) {
806 rc = b_addchr(o, '\\');
810 return b_addchr(o, ch);
813 static int b_adduint(o_string *o, unsigned i)
816 char buf[sizeof(unsigned)*3 + 1];
818 *(utoa_to_buf(i, buf, sizeof(buf))) = '\0';
819 /* no escape checking necessary */
820 do r = b_addchr(o, *p++); while (r == 0 && *p);
824 static int static_get(struct in_str *i)
827 if (ch == '\0') return EOF;
831 static int static_peek(struct in_str *i)
836 static void cmdedit_set_initial_prompt(void)
838 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
847 static const char* setup_prompt_string(int promptmode)
849 const char *prompt_str;
850 debug_printf("setup_prompt_string %d ", promptmode);
851 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
852 /* Set up the prompt */
853 if (promptmode == 1) {
856 ns = xmalloc(strlen(cwd)+4);
857 sprintf(ns, "%s %s", cwd, (geteuid() != 0) ? "$ " : "# ");
864 prompt_str = (promptmode == 1) ? PS1 : PS2;
866 debug_printf("result %s\n", prompt_str);
870 #if ENABLE_FEATURE_EDITING
871 static line_input_t *line_input_state;
874 static void get_user_input(struct in_str *i)
876 const char *prompt_str;
877 static char the_command[BUFSIZ];
879 prompt_str = setup_prompt_string(i->promptmode);
880 #if ENABLE_FEATURE_EDITING
882 ** enable command line editing only while a command line
883 ** is actually being read; otherwise, we'll end up bequeathing
884 ** atexit() handlers and other unwanted stuff to our
885 ** child processes (rob@sysgo.de)
887 read_line_input(prompt_str, the_command, BUFSIZ, line_input_state);
889 fputs(prompt_str, stdout);
891 the_command[0] = fgetc(i->file);
892 the_command[1] = '\0';
898 /* This is the magic location that prints prompts
899 * and gets data back from the user */
900 static int file_get(struct in_str *i)
905 /* If there is data waiting, eat it up */
909 /* need to double check i->file because we might be doing something
910 * more complicated by now, like sourcing or substituting. */
911 if (i->__promptme && interactive && i->file == stdin) {
912 while (!i->p || !(interactive && strlen(i->p))) {
924 debug_printf("b_getch: got a %d\n", ch);
931 /* All the callers guarantee this routine will never be
932 * used right after a newline, so prompting is not needed.
934 static int file_peek(struct in_str *i)
939 i->peek_buf[0] = fgetc(i->file);
940 i->peek_buf[1] = '\0';
942 debug_printf("b_peek: got a %d\n", *i->p);
946 static void setup_file_in_str(struct in_str *i, FILE *f)
956 static void setup_string_in_str(struct in_str *i, const char *s)
958 i->peek = static_peek;
965 static void mark_open(int fd)
967 struct close_me *new = xmalloc(sizeof(struct close_me));
969 new->next = close_me_head;
973 static void mark_closed(int fd)
975 struct close_me *tmp;
976 if (close_me_head == NULL || close_me_head->fd != fd)
977 bb_error_msg_and_die("corrupt close_me");
979 close_me_head = close_me_head->next;
983 static void close_all(void)
986 for (c = close_me_head; c; c = c->next) {
989 close_me_head = NULL;
992 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
993 * and stderr if they are redirected. */
994 static int setup_redirects(struct child_prog *prog, int squirrel[])
997 struct redir_struct *redir;
999 for (redir = prog->redirects; redir; redir = redir->next) {
1000 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1001 /* something went wrong in the parse. Pretend it didn't happen */
1004 if (redir->dup == -1) {
1005 mode = redir_table[redir->type].mode;
1006 openfd = open_or_warn(redir->word.gl_pathv[0], mode);
1008 /* this could get lost if stderr has been redirected, but
1009 bash and ash both lose it as well (though zsh doesn't!) */
1013 openfd = redir->dup;
1016 if (openfd != redir->fd) {
1017 if (squirrel && redir->fd < 3) {
1018 squirrel[redir->fd] = dup(redir->fd);
1023 dup2(openfd, redir->fd);
1024 if (redir->dup == -1)
1032 static void restore_redirects(int squirrel[])
1035 for (i = 0; i < 3; i++) {
1038 /* No error checking. I sure wouldn't know what
1039 * to do with an error if I found one! */
1047 /* XXX no exit() here. If you don't exec, use _exit instead.
1048 * The at_exit handlers apparently confuse the calling process,
1049 * in particular stdin handling. Not sure why? */
1050 static void pseudo_exec(struct child_prog *child)
1054 const struct built_in_command *x;
1056 for (i = 0; is_assignment(child->argv[i]); i++) {
1057 debug_printf("pid %d environment modification: %s\n",
1058 getpid(), child->argv[i]);
1059 p = insert_var_value(child->argv[i]);
1061 if (p != child->argv[i])
1064 child->argv += i; /* XXX this hack isn't so horrible, since we are about
1065 to exit, and therefore don't need to keep data
1066 structures consistent for free() use. */
1067 /* If a variable is assigned in a forest, and nobody listens,
1068 * was it ever really set?
1070 if (child->argv[0] == NULL) {
1071 _exit(EXIT_SUCCESS);
1075 * Check if the command matches any of the builtins.
1076 * Depending on context, this might be redundant. But it's
1077 * easier to waste a few CPU cycles than it is to figure out
1078 * if this is one of those cases.
1080 for (x = bltins; x->cmd; x++) {
1081 if (strcmp(child->argv[0], x->cmd) == 0) {
1082 debug_printf("builtin exec %s\n", child->argv[0]);
1083 rcode = x->function(child);
1089 /* Check if the command matches any busybox internal commands
1091 * FIXME: This feature is not 100% safe, since
1092 * BusyBox is not fully reentrant, so we have no guarantee the things
1093 * from the .bss are still zeroed, or that things from .data are still
1094 * at their defaults. We could exec ourself from /proc/self/exe, but I
1095 * really dislike relying on /proc for things. We could exec ourself
1096 * from global_argv[0], but if we are in a chroot, we may not be able
1097 * to find ourself... */
1098 #if ENABLE_FEATURE_SH_STANDALONE
1099 debug_printf("running applet %s\n", child->argv[0]);
1100 run_applet_and_exit(child->argv[0], child->argv);
1101 // is it ok that run_applet_and_exit() does exit(), not _exit()?
1102 // NB: IIRC on NOMMU we are after _vfork_, not fork!
1104 debug_printf("exec of %s\n", child->argv[0]);
1105 execvp(child->argv[0], child->argv);
1106 bb_perror_msg("cannot exec: %s", child->argv[0]);
1111 debug_printf("runtime nesting to group\n");
1112 interactive = 0; /* crucial!!!! */
1113 rcode = run_list_real(child->group);
1114 /* OK to leak memory by not calling free_pipe_list,
1115 * since this process is about to exit */
1119 /* Can happen. See what bash does with ">foo" by itself. */
1120 debug_printf("trying to pseudo_exec null command\n");
1121 _exit(EXIT_SUCCESS);
1124 static void insert_bg_job(struct pipe *pi)
1126 struct pipe *thejob;
1128 /* Linear search for the ID of the job to use */
1130 for (thejob = job_list; thejob; thejob = thejob->next)
1131 if (thejob->jobid >= pi->jobid)
1132 pi->jobid = thejob->jobid + 1;
1134 /* add thejob to the list of running jobs */
1136 thejob = job_list = xmalloc(sizeof(*thejob));
1138 for (thejob = job_list; thejob->next; thejob = thejob->next)
1140 thejob->next = xmalloc(sizeof(*thejob));
1141 thejob = thejob->next;
1144 /* physically copy the struct job */
1145 memcpy(thejob, pi, sizeof(struct pipe));
1146 thejob->next = NULL;
1147 thejob->running_progs = thejob->num_progs;
1148 thejob->stopped_progs = 0;
1149 thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1151 //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0])
1153 char *bar = thejob->text;
1154 char **foo = pi->progs[0].argv;
1157 bar += sprintf(bar, "%s ", *foo++);
1160 /* we don't wait for background thejobs to return -- append it
1161 to the list of backgrounded thejobs and leave it alone */
1162 printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1163 last_bg_pid = thejob->progs[0].pid;
1164 last_jobid = thejob->jobid;
1167 /* remove a backgrounded job */
1168 static void remove_bg_job(struct pipe *pi)
1170 struct pipe *prev_pipe;
1172 if (pi == job_list) {
1173 job_list = pi->next;
1175 prev_pipe = job_list;
1176 while (prev_pipe->next != pi)
1177 prev_pipe = prev_pipe->next;
1178 prev_pipe->next = pi->next;
1181 last_jobid = job_list->jobid;
1185 pi->stopped_progs = 0;
1190 /* Checks to see if any processes have exited -- if they
1191 have, figure out why and see if a job has completed */
1192 static int checkjobs(struct pipe* fg_pipe)
1200 attributes = WUNTRACED;
1201 if (fg_pipe == NULL) {
1202 attributes |= WNOHANG;
1205 while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1208 for (i = 0; i < fg_pipe->num_progs; i++) {
1209 if (fg_pipe->progs[i].pid == childpid) {
1210 if (i == fg_pipe->num_progs-1)
1211 rcode = WEXITSTATUS(status);
1212 fg_pipe->num_progs--;
1218 for (pi = job_list; pi; pi = pi->next) {
1220 while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1223 if (prognum < pi->num_progs)
1228 debug_printf("checkjobs: pid %d was not in our list!\n",
1233 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1235 pi->running_progs--;
1236 pi->progs[prognum].pid = 0;
1238 if (!pi->running_progs) {
1239 printf(JOB_STATUS_FORMAT, pi->jobid,
1245 pi->stopped_progs++;
1246 pi->progs[prognum].is_stopped = 1;
1250 if (childpid == -1 && errno != ECHILD)
1251 bb_perror_msg("waitpid");
1253 /* move the shell to the foreground */
1254 //if (interactive && tcsetpgrp(shell_terminal, getpgid(0)))
1255 // bb_perror_msg("tcsetpgrp-2");
1259 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1260 * to finish. See checkjobs().
1262 * return code is normally -1, when the caller has to wait for children
1263 * to finish to determine the exit status of the pipe. If the pipe
1264 * is a simple builtin command, however, the action is done by the
1265 * time run_pipe_real returns, and the exit code is provided as the
1268 * The input of the pipe is always stdin, the output is always
1269 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1270 * because it tries to avoid running the command substitution in
1271 * subshell, when that is in fact necessary. The subshell process
1272 * now has its stdout directed to the input of the appropriate pipe,
1273 * so this routine is noticeably simpler.
1275 static int run_pipe_real(struct pipe *pi)
1278 int nextin, nextout;
1279 int pipefds[2]; /* pipefds[0] is for reading */
1280 struct child_prog *child;
1281 const struct built_in_command *x;
1283 /* it is not always needed, but we aim to smaller code */
1284 int squirrel[] = { -1, -1, -1 };
1290 /* Check if this is a simple builtin (not part of a pipe).
1291 * Builtins within pipes have to fork anyway, and are handled in
1292 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1294 child = &(pi->progs[0]);
1295 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1296 debug_printf("non-subshell grouping\n");
1297 setup_redirects(child, squirrel);
1298 /* XXX could we merge code with following builtin case,
1299 * by creating a pseudo builtin that calls run_list_real? */
1300 rcode = run_list_real(child->group);
1301 restore_redirects(squirrel);
1305 if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1306 for (i = 0; is_assignment(child->argv[i]); i++)
1308 if (i != 0 && child->argv[i] == NULL) {
1309 /* assignments, but no command: set the local environment */
1310 for (i = 0; child->argv[i] != NULL; i++) {
1311 /* Ok, this case is tricky. We have to decide if this is a
1312 * local variable, or an already exported variable. If it is
1313 * already exported, we have to export the new value. If it is
1314 * not exported, we need only set this as a local variable.
1315 * This junk is all to decide whether or not to export this
1319 name = xstrdup(child->argv[i]);
1320 debug_printf("Local environment set: %s\n", name);
1321 value = strchr(name, '=');
1324 if (get_local_var(name)) {
1328 p = insert_var_value(child->argv[i]);
1329 set_local_var(p, export_me);
1330 if (p != child->argv[i])
1333 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1335 for (i = 0; is_assignment(child->argv[i]); i++) {
1336 p = insert_var_value(child->argv[i]);
1338 if (p != child->argv[i]) {
1346 str = make_string(child->argv + i);
1347 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1349 return last_return_code;
1351 for (x = bltins; x->cmd; x++) {
1352 if (strcmp(child->argv[i], x->cmd) == 0) {
1353 if (x->function == builtin_exec && child->argv[i+1] == NULL) {
1354 debug_printf("magic exec\n");
1355 setup_redirects(child, NULL);
1356 return EXIT_SUCCESS;
1358 debug_printf("builtin inline %s\n", child->argv[0]);
1359 /* XXX setup_redirects acts on file descriptors, not FILEs.
1360 * This is perfect for work that comes after exec().
1361 * Is it really safe for inline use? Experimentally,
1362 * things seem to work with glibc. */
1363 setup_redirects(child, squirrel);
1364 child->argv += i; /* XXX horrible hack */
1365 rcode = x->function(child);
1366 child->argv -= i; /* XXX restore hack so free() can work right */
1367 restore_redirects(squirrel);
1371 #if ENABLE_FEATURE_SH_STANDALONE
1373 const struct bb_applet *a = find_applet_by_name(child->argv[i]);
1374 if (a && a->nofork) {
1375 setup_redirects(child, squirrel);
1376 rcode = run_nofork_applet(a, child->argv + i);
1377 restore_redirects(squirrel);
1384 for (i = 0; i < pi->num_progs; i++) {
1385 child = &(pi->progs[i]);
1387 /* pipes are inserted between pairs of commands */
1388 if ((i + 1) < pi->num_progs) {
1389 if (pipe(pipefds) < 0)
1390 bb_perror_msg_and_die("pipe");
1391 nextout = pipefds[1];
1397 /* XXX test for failed fork()? */
1399 child->pid = fork();
1401 child->pid = vfork();
1404 /* Set the handling for job control signals back to the default. */
1405 signal(SIGINT, SIG_DFL);
1406 signal(SIGQUIT, SIG_DFL);
1407 signal(SIGTERM, SIG_DFL);
1408 signal(SIGTSTP, SIG_DFL);
1409 signal(SIGTTIN, SIG_DFL);
1410 signal(SIGTTOU, SIG_DFL);
1411 signal(SIGCHLD, SIG_DFL);
1423 if (pipefds[0] != -1) {
1424 close(pipefds[0]); /* opposite end of our output pipe */
1427 /* Like bash, explicit redirects override pipes,
1428 * and the pipe fd is available for dup'ing. */
1429 setup_redirects(child, NULL);
1431 if (interactive && pi->followup != PIPE_BG) {
1432 /* If we (the child) win the race, put ourselves in the process
1433 * group whose leader is the first process in this pipe. */
1435 pi->pgrp = getpid();
1437 if (setpgid(0, pi->pgrp) == 0) {
1438 tcsetpgrp(2, pi->pgrp);
1445 /* put our child in the process group whose leader is the
1446 first process in this pipe */
1448 pi->pgrp = child->pid;
1450 /* Don't check for errors. The child may be dead already,
1451 * in which case setpgid returns error code EACCES. */
1452 setpgid(child->pid, pi->pgrp);
1459 /* If there isn't another process, nextin is garbage
1460 but it doesn't matter */
1461 nextin = pipefds[0];
1466 static int run_list_real(struct pipe *pi)
1468 char *save_name = NULL;
1470 char **save_list = NULL;
1474 int rcode = 0, flag_skip = 1;
1475 int flag_restore = 0;
1476 int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
1477 reserved_style rmode, skip_more_in_this_rmode = RES_XXXX;
1478 /* check syntax for "for" */
1479 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1480 if ((rpipe->r_mode == RES_IN || rpipe->r_mode == RES_FOR)
1481 && (rpipe->next == NULL)
1486 if ((rpipe->r_mode == RES_IN && rpipe->next->r_mode == RES_IN && rpipe->next->progs->argv != NULL)
1487 || (rpipe->r_mode == RES_FOR && rpipe->next->r_mode != RES_IN)
1493 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1494 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL
1495 || pi->r_mode == RES_FOR
1504 debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n",
1505 rmode, if_code, next_if_code, skip_more_in_this_rmode);
1506 if (rmode == skip_more_in_this_rmode && flag_skip) {
1507 if (pi->followup == PIPE_SEQ)
1512 skip_more_in_this_rmode = RES_XXXX;
1513 if (rmode == RES_THEN || rmode == RES_ELSE)
1514 if_code = next_if_code;
1515 if (rmode == RES_THEN && if_code)
1517 if (rmode == RES_ELSE && !if_code)
1519 if (rmode == RES_ELIF && !if_code)
1521 if (rmode == RES_FOR && pi->num_progs) {
1523 /* if no variable values after "in" we skip "for" */
1524 if (!pi->next->progs->argv)
1526 /* create list of variable values */
1527 list = make_list_in(pi->next->progs->argv,
1528 pi->progs->argv[0]);
1530 save_name = pi->progs->argv[0];
1531 pi->progs->argv[0] = NULL;
1535 free(pi->progs->argv[0]);
1539 pi->progs->argv[0] = save_name;
1540 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1543 /* insert new value from list for variable */
1544 if (pi->progs->argv[0])
1545 free(pi->progs->argv[0]);
1546 pi->progs->argv[0] = *list++;
1547 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1550 if (rmode == RES_IN)
1552 if (rmode == RES_DO) {
1556 if ((rmode == RES_DONE)) {
1563 if (pi->num_progs == 0)
1565 save_num_progs = pi->num_progs; /* save number of programs */
1566 rcode = run_pipe_real(pi);
1567 debug_printf("run_pipe_real returned %d\n", rcode);
1569 /* We only ran a builtin: rcode was set by the return value
1570 * of run_pipe_real(), and we don't need to wait for anything. */
1571 } else if (pi->followup == PIPE_BG) {
1572 /* XXX check bash's behavior with nontrivial pipes */
1573 /* XXX compute jobid */
1574 /* XXX what does bash do with attempts to background builtins? */
1576 rcode = EXIT_SUCCESS;
1579 /* move the new process group into the foreground */
1580 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1581 bb_perror_msg("tcsetpgrp-3");
1582 rcode = checkjobs(pi);
1583 /* move the shell to the foreground */
1584 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1585 bb_perror_msg("tcsetpgrp-4");
1587 rcode = checkjobs(pi);
1589 debug_printf("checkjobs returned %d\n", rcode);
1591 last_return_code = rcode;
1592 pi->num_progs = save_num_progs; /* restore number of programs */
1593 if ( rmode == RES_IF || rmode == RES_ELIF )
1594 next_if_code = rcode; /* can be overwritten a number of times */
1595 if (rmode == RES_WHILE)
1596 flag_rep = !last_return_code;
1597 if (rmode == RES_UNTIL)
1598 flag_rep = last_return_code;
1599 if ((rcode == EXIT_SUCCESS && pi->followup == PIPE_OR)
1600 || (rcode != EXIT_SUCCESS && pi->followup == PIPE_AND)
1602 skip_more_in_this_rmode = rmode;
1609 /* return code is the exit status of the pipe */
1610 static int free_pipe(struct pipe *pi, int indent)
1613 struct child_prog *child;
1614 struct redir_struct *r, *rnext;
1615 int a, i, ret_code = 0;
1617 if (pi->stopped_progs > 0)
1619 final_printf("%s run pipe: (pid %d)\n", indenter(indent), getpid());
1620 for (i = 0; i < pi->num_progs; i++) {
1621 child = &pi->progs[i];
1622 final_printf("%s command %d:\n", indenter(indent), i);
1624 for (a = 0, p = child->argv; *p; a++, p++) {
1625 final_printf("%s argv[%d] = %s\n", indenter(indent), a, *p);
1627 globfree(&child->glob_result);
1629 } else if (child->group) {
1630 final_printf("%s begin group (subshell:%d)\n", indenter(indent), child->subshell);
1631 ret_code = free_pipe_list(child->group, indent+3);
1632 final_printf("%s end group\n", indenter(indent));
1634 final_printf("%s (nil)\n", indenter(indent));
1636 for (r = child->redirects; r; r = rnext) {
1637 final_printf("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip);
1639 /* guard against the case >$FOO, where foo is unset or blank */
1640 if (r->word.gl_pathv) {
1641 final_printf(" %s\n", *r->word.gl_pathv);
1645 final_printf("&%d\n", r->dup);
1650 child->redirects = NULL;
1652 free(pi->progs); /* children are an array, they get freed all at once */
1657 static int free_pipe_list(struct pipe *head, int indent)
1659 int rcode = 0; /* if list has no members */
1660 struct pipe *pi, *next;
1661 for (pi = head; pi; pi = next) {
1662 final_printf("%s pipe reserved mode %d\n", indenter(indent), pi->r_mode);
1663 rcode = free_pipe(pi, indent);
1664 final_printf("%s pipe followup code %d\n", indenter(indent), pi->followup);
1672 /* Select which version we will use */
1673 static int run_list(struct pipe *pi)
1676 if (fake_mode == 0) {
1677 rcode = run_list_real(pi);
1679 /* free_pipe_list has the side effect of clearing memory
1680 * In the long run that function can be merged with run_list_real,
1681 * but doing that now would hobble the debugging effort. */
1682 free_pipe_list(pi,0);
1686 /* The API for glob is arguably broken. This routine pushes a non-matching
1687 * string into the output structure, removing non-backslashed backslashes.
1688 * If someone can prove me wrong, by performing this function within the
1689 * original glob(3) api, feel free to rewrite this routine into oblivion.
1690 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
1691 * XXX broken if the last character is '\\', check that before calling.
1693 static int globhack(const char *src, int flags, glob_t *pglob)
1698 for (cnt = 1, s = src; s && *s; s++) {
1699 if (*s == '\\') s++;
1703 if (!dest) return GLOB_NOSPACE;
1704 if (!(flags & GLOB_APPEND)) {
1705 pglob->gl_pathv = NULL;
1706 pglob->gl_pathc = 0;
1710 pathc = ++pglob->gl_pathc;
1711 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
1712 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
1713 pglob->gl_pathv[pathc-1] = dest;
1714 pglob->gl_pathv[pathc] = NULL;
1715 for (s = src; s && *s; s++, dest++) {
1716 if (*s == '\\') s++;
1723 /* XXX broken if the last character is '\\', check that before calling */
1724 static int glob_needed(const char *s)
1727 if (*s == '\\') s++;
1728 if (strchr("*[?", *s)) return 1;
1733 static int xglob(o_string *dest, int flags, glob_t *pglob)
1737 /* short-circuit for null word */
1738 /* we can code this better when the debug_printf's are gone */
1739 if (dest->length == 0) {
1740 if (dest->nonnull) {
1741 /* bash man page calls this an "explicit" null */
1742 gr = globhack(dest->data, flags, pglob);
1743 debug_printf("globhack returned %d\n", gr);
1747 } else if (glob_needed(dest->data)) {
1748 gr = glob(dest->data, flags, NULL, pglob);
1749 debug_printf("glob returned %d\n", gr);
1750 if (gr == GLOB_NOMATCH) {
1751 /* quote removal, or more accurately, backslash removal */
1752 gr = globhack(dest->data, flags, pglob);
1753 debug_printf("globhack returned %d\n", gr);
1756 gr = globhack(dest->data, flags, pglob);
1757 debug_printf("globhack returned %d\n", gr);
1759 if (gr == GLOB_NOSPACE)
1760 bb_error_msg_and_die("out of memory during glob");
1761 if (gr != 0) { /* GLOB_ABORTED ? */
1762 bb_error_msg("glob(3) error %d", gr);
1764 /* globprint(glob_target); */
1768 /* This is used to get/check local shell variables */
1769 static const char *get_local_var(const char *s)
1771 struct variables *cur;
1775 for (cur = top_vars; cur; cur = cur->next)
1776 if (strcmp(cur->name, s) == 0)
1781 /* This is used to set local shell variables
1782 flg_export == 0 if only local (not exporting) variable
1783 flg_export == 1 if "new" exporting environ
1784 flg_export > 1 if current startup environ (not call putenv()) */
1785 static int set_local_var(const char *s, int flg_export)
1789 struct variables *cur;
1793 /* Assume when we enter this function that we are already in
1794 * NAME=VALUE format. So the first order of business is to
1795 * split 's' on the '=' into 'name' and 'value' */
1796 value = strchr(name, '=');
1797 /*if (value == 0 && ++value == 0) ??? -vda */
1798 if (value == NULL || value[1] == '\0') {
1804 for (cur = top_vars; cur; cur = cur->next) {
1805 if (strcmp(cur->name, name) == 0)
1810 if (strcmp(cur->value, value) == 0) {
1811 if (flg_export > 0 && cur->flg_export == 0)
1812 cur->flg_export = flg_export;
1815 } else if (cur->flg_read_only) {
1816 bb_error_msg("%s: readonly variable", name);
1819 if (flg_export > 0 || cur->flg_export > 1)
1820 cur->flg_export = 1;
1821 free((char*)cur->value);
1823 cur->value = strdup(value);
1826 cur = malloc(sizeof(struct variables));
1830 cur->name = strdup(name);
1835 struct variables *bottom = top_vars;
1836 cur->value = strdup(value);
1838 cur->flg_export = flg_export;
1839 cur->flg_read_only = 0;
1840 while (bottom->next)
1841 bottom = bottom->next;
1847 if (result == 0 && cur->flg_export == 1) {
1849 result = putenv(name);
1852 if (result > 0) /* equivalent to previous set */
1858 static void unset_local_var(const char *name)
1860 struct variables *cur;
1863 for (cur = top_vars; cur; cur = cur->next) {
1864 if (strcmp(cur->name, name) == 0)
1868 struct variables *next = top_vars;
1869 if (cur->flg_read_only) {
1870 bb_error_msg("%s: readonly variable", name);
1873 if (cur->flg_export)
1874 unsetenv(cur->name);
1875 free((char*)cur->name);
1876 free((char*)cur->value);
1877 while (next->next != cur)
1879 next->next = cur->next;
1885 static int is_assignment(const char *s)
1887 if (!s || !isalpha(*s))
1890 while (isalnum(*s) || *s == '_')
1895 /* the src parameter allows us to peek forward to a possible &n syntax
1896 * for file descriptor duplication, e.g., "2>&1".
1897 * Return code is 0 normally, 1 if a syntax error is detected in src.
1898 * Resource errors (in xmalloc) cause the process to exit */
1899 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
1900 struct in_str *input)
1902 struct child_prog *child = ctx->child;
1903 struct redir_struct *redir = child->redirects;
1904 struct redir_struct *last_redir = NULL;
1906 /* Create a new redir_struct and drop it onto the end of the linked list */
1909 redir = redir->next;
1911 redir = xmalloc(sizeof(struct redir_struct));
1913 redir->word.gl_pathv = NULL;
1915 last_redir->next = redir;
1917 child->redirects = redir;
1920 redir->type = style;
1921 redir->fd = (fd == -1) ? redir_table[style].default_fd : fd;
1923 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
1925 /* Check for a '2>&1' type redirect */
1926 redir->dup = redirect_dup_num(input);
1927 if (redir->dup == -2) return 1; /* syntax error */
1928 if (redir->dup != -1) {
1929 /* Erik had a check here that the file descriptor in question
1930 * is legit; I postpone that to "run time"
1931 * A "-" representation of "close me" shows up as a -3 here */
1932 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
1934 /* We do _not_ try to open the file that src points to,
1935 * since we need to return and let src be expanded first.
1936 * Set ctx->pending_redirect, so we know what to do at the
1937 * end of the next parsed word.
1939 ctx->pending_redirect = redir;
1944 static struct pipe *new_pipe(void)
1947 pi = xmalloc(sizeof(struct pipe));
1951 pi->followup = 0; /* invalid */
1952 pi->r_mode = RES_NONE;
1956 static void initialize_context(struct p_context *ctx)
1959 ctx->pending_redirect = NULL;
1961 ctx->list_head = new_pipe();
1962 ctx->pipe = ctx->list_head;
1966 done_command(ctx); /* creates the memory for working child */
1969 /* normal return is 0
1970 * if a reserved word is found, and processed, return 1
1971 * should handle if, then, elif, else, fi, for, while, until, do, done.
1972 * case, function, and select are obnoxious, save those for later.
1974 static int reserved_word(o_string *dest, struct p_context *ctx)
1976 struct reserved_combo {
1977 const char *literal;
1981 /* Mostly a list of accepted follow-up reserved words.
1982 * FLAG_END means we are done with the sequence, and are ready
1983 * to turn the compound list into a command.
1984 * FLAG_START means the word must start a new compound list.
1986 static const struct reserved_combo reserved_list[] = {
1987 { "if", RES_IF, FLAG_THEN | FLAG_START },
1988 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
1989 { "elif", RES_ELIF, FLAG_THEN },
1990 { "else", RES_ELSE, FLAG_FI },
1991 { "fi", RES_FI, FLAG_END },
1992 { "for", RES_FOR, FLAG_IN | FLAG_START },
1993 { "while", RES_WHILE, FLAG_DO | FLAG_START },
1994 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
1995 { "in", RES_IN, FLAG_DO },
1996 { "do", RES_DO, FLAG_DONE },
1997 { "done", RES_DONE, FLAG_END }
1999 enum { NRES = sizeof(reserved_list)/sizeof(reserved_list[0]) };
2000 const struct reserved_combo *r;
2002 for (r = reserved_list; r < reserved_list+NRES; r++) {
2003 if (strcmp(dest->data, r->literal) == 0) {
2004 debug_printf("found reserved word %s, code %d\n", r->literal, r->code);
2005 if (r->flag & FLAG_START) {
2006 struct p_context *new = xmalloc(sizeof(struct p_context));
2007 debug_printf("push stack\n");
2008 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2015 *new = *ctx; /* physical copy */
2016 initialize_context(ctx);
2018 } else if (ctx->w == RES_NONE || !(ctx->old_flag & (1 << r->code))) {
2025 ctx->old_flag = r->flag;
2026 if (ctx->old_flag & FLAG_END) {
2027 struct p_context *old;
2028 debug_printf("pop stack\n");
2029 done_pipe(ctx, PIPE_SEQ);
2031 old->child->group = ctx->list_head;
2032 old->child->subshell = 0;
2033 *ctx = *old; /* physical copy */
2043 /* normal return is 0.
2044 * Syntax or xglob errors return 1. */
2045 static int done_word(o_string *dest, struct p_context *ctx)
2047 struct child_prog *child = ctx->child;
2048 glob_t *glob_target;
2051 debug_printf("done_word: %s %p\n", dest->data, child);
2052 if (dest->length == 0 && !dest->nonnull) {
2053 debug_printf(" true null, ignored\n");
2056 if (ctx->pending_redirect) {
2057 glob_target = &ctx->pending_redirect->word;
2061 return 1; /* syntax error, groups and arglists don't mix */
2063 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2064 debug_printf("checking %s for reserved-ness\n", dest->data);
2065 if (reserved_word(dest, ctx))
2066 return (ctx->w == RES_SNTX);
2068 glob_target = &child->glob_result;
2069 if (child->argv) flags |= GLOB_APPEND;
2071 gr = xglob(dest, flags, glob_target);
2072 if (gr != 0) return 1;
2075 if (ctx->pending_redirect) {
2076 ctx->pending_redirect = NULL;
2077 if (glob_target->gl_pathc != 1) {
2078 bb_error_msg("ambiguous redirect");
2082 child->argv = glob_target->gl_pathv;
2084 if (ctx->w == RES_FOR) {
2085 done_word(dest, ctx);
2086 done_pipe(ctx, PIPE_SEQ);
2091 /* The only possible error here is out of memory, in which case
2093 static int done_command(struct p_context *ctx)
2095 /* The child is really already in the pipe structure, so
2096 * advance the pipe counter and make a new, null child.
2097 * Only real trickiness here is that the uncommitted
2098 * child structure, to which ctx->child points, is not
2099 * counted in pi->num_progs. */
2100 struct pipe *pi = ctx->pipe;
2101 struct child_prog *prog = ctx->child;
2103 if (prog && prog->group == NULL
2104 && prog->argv == NULL
2105 && prog->redirects == NULL
2107 debug_printf("done_command: skipping null command\n");
2112 debug_printf("done_command: num_progs incremented to %d\n", pi->num_progs);
2114 debug_printf("done_command: initializing\n");
2116 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2118 prog = pi->progs + pi->num_progs;
2119 prog->redirects = NULL;
2121 prog->is_stopped = 0;
2123 prog->glob_result.gl_pathv = NULL;
2127 prog->type = ctx->type;
2129 /* but ctx->pipe and ctx->list_head remain unchanged */
2133 static int done_pipe(struct p_context *ctx, pipe_style type)
2136 done_command(ctx); /* implicit closure of previous command */
2137 debug_printf("done_pipe, type %d\n", type);
2138 ctx->pipe->followup = type;
2139 ctx->pipe->r_mode = ctx->w;
2141 ctx->pipe->next = new_p;
2144 done_command(ctx); /* set up new pipe to accept commands */
2148 /* peek ahead in the in_str to find out if we have a "&n" construct,
2149 * as in "2>&1", that represents duplicating a file descriptor.
2150 * returns either -2 (syntax error), -1 (no &), or the number found.
2152 static int redirect_dup_num(struct in_str *input)
2154 int ch, d = 0, ok = 0;
2156 if (ch != '&') return -1;
2158 b_getch(input); /* get the & */
2162 return -3; /* "-" represents "close me" */
2164 while (isdigit(ch)) {
2165 d = d*10 + (ch-'0');
2172 bb_error_msg("ambiguous redirect");
2176 /* If a redirect is immediately preceded by a number, that number is
2177 * supposed to tell which file descriptor to redirect. This routine
2178 * looks for such preceding numbers. In an ideal world this routine
2179 * needs to handle all the following classes of redirects...
2180 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2181 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2182 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2183 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2184 * A -1 output from this program means no valid number was found, so the
2185 * caller should use the appropriate default for this redirection.
2187 static int redirect_opt_num(o_string *o)
2193 for (num = 0; num < o->length; num++) {
2194 if (!isdigit(*(o->data + num))) {
2198 /* reuse num (and save an int) */
2199 num = atoi(o->data);
2204 static FILE *generate_stream_from_list(struct pipe *head)
2207 int pid, channel[2];
2208 if (pipe(channel) < 0) bb_perror_msg_and_die("pipe");
2215 bb_perror_msg_and_die("fork");
2216 } else if (pid == 0) {
2218 if (channel[1] != 1) {
2219 dup2(channel[1], 1);
2222 _exit(run_list_real(head)); /* leaks memory */
2224 debug_printf("forked child %d\n", pid);
2226 pf = fdopen(channel[0],"r");
2227 debug_printf("pipe on FILE *%p\n", pf);
2231 /* this version hacked for testing purposes */
2232 /* return code is exit status of the process that is run. */
2233 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2236 o_string result = NULL_O_STRING;
2237 struct p_context inner;
2239 struct in_str pipe_str;
2240 initialize_context(&inner);
2242 /* recursion to generate command */
2243 retcode = parse_stream(&result, &inner, input, subst_end);
2244 if (retcode != 0) return retcode; /* syntax error or EOF */
2245 done_word(&result, &inner);
2246 done_pipe(&inner, PIPE_SEQ);
2249 p = generate_stream_from_list(inner.list_head);
2250 if (p == NULL) return 1;
2251 mark_open(fileno(p));
2252 setup_file_in_str(&pipe_str, p);
2254 /* now send results of command back into original context */
2255 retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2256 /* XXX In case of a syntax error, should we try to kill the child?
2257 * That would be tough to do right, so just read until EOF. */
2259 while (b_getch(&pipe_str) != EOF)
2263 debug_printf("done reading from pipe, pclose()ing\n");
2264 /* This is the step that wait()s for the child. Should be pretty
2265 * safe, since we just read an EOF from its stdout. We could try
2266 * to better, by using wait(), and keeping track of background jobs
2267 * at the same time. That would be a lot of work, and contrary
2268 * to the KISS philosophy of this program. */
2269 mark_closed(fileno(p));
2270 retcode = pclose(p);
2271 free_pipe_list(inner.list_head, 0);
2272 debug_printf("pclosed, retcode=%d\n", retcode);
2273 /* XXX this process fails to trim a single trailing newline */
2277 static int parse_group(o_string *dest, struct p_context *ctx,
2278 struct in_str *input, int ch)
2280 int rcode, endch = 0;
2281 struct p_context sub;
2282 struct child_prog *child = ctx->child;
2285 return 1; /* syntax error, groups and arglists don't mix */
2287 initialize_context(&sub);
2291 child->subshell = 1;
2297 syntax(); /* really logic error */
2299 rcode = parse_stream(dest, &sub, input, endch);
2300 done_word(dest, &sub); /* finish off the final word in the subcontext */
2301 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2302 child->group = sub.list_head;
2304 /* child remains "open", available for possible redirects */
2307 /* basically useful version until someone wants to get fancier,
2308 * see the bash man page under "Parameter Expansion" */
2309 static const char *lookup_param(const char *src)
2311 const char *p = NULL;
2315 p = get_local_var(src);
2320 /* return code: 0 for OK, 1 for syntax error */
2321 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2325 int ch = input->peek(input); /* first character after the $ */
2326 debug_printf("handle_dollar: ch=%c\n", ch);
2328 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2330 while (ch = b_peek(input), isalnum(ch) || ch == '_') {
2334 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2335 } else if (isdigit(ch)) {
2336 i = ch-'0'; /* XXX is $0 special? */
2337 if (i < global_argc) {
2338 parse_string(dest, ctx, global_argv[i]); /* recursion */
2341 } else switch (ch) {
2343 b_adduint(dest, getpid());
2347 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2351 b_adduint(dest, last_return_code);
2355 b_adduint(dest, global_argc ? global_argc-1 : 0);
2359 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2362 /* XXX maybe someone will try to escape the '}' */
2364 ch = b_getch(input);
2365 if (ch == EOF || ch == '}')
2373 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2377 process_command_subs(dest, ctx, input, ')');
2381 for (i = 1; i < global_argc; i++) {
2382 parse_string(dest, ctx, global_argv[i]);
2383 if (i+1 < global_argc)
2384 parse_string(dest, ctx, sep);
2390 /* still unhandled, but should be eventually */
2391 bb_error_msg("unhandled syntax: $%c", ch);
2395 b_addqchr(dest,'$', dest->quote);
2397 /* Eat the character if the flag was set. If the compiler
2398 * is smart enough, we could substitute "b_getch(input);"
2399 * for all the "advance = 1;" above, and also end up with
2400 * a nice size-optimized program. Hah! That'll be the day.
2402 if (advance) b_getch(input);
2406 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2409 setup_string_in_str(&foo, src);
2410 return parse_stream(dest, ctx, &foo, '\0');
2413 /* return code is 0 for normal exit, 1 for syntax error */
2414 int parse_stream(o_string *dest, struct p_context *ctx,
2415 struct in_str *input, int end_trigger)
2419 redir_type redir_style;
2422 /* Only double-quote state is handled in the state variable dest->quote.
2423 * A single-quote triggers a bypass of the main loop until its mate is
2424 * found. When recursing, quote state is passed in via dest->quote. */
2426 debug_printf("parse_stream, end_trigger=%d\n", end_trigger);
2427 while ((ch = b_getch(input)) != EOF) {
2429 next = (ch == '\n') ? 0 : b_peek(input);
2430 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
2431 ch, ch, m, dest->quote);
2432 if (m == 0 || ((m == 1 || m == 2) && dest->quote)) {
2433 b_addqchr(dest, ch, dest->quote);
2436 if (m == 2) { /* unquoted IFS */
2437 if (done_word(dest, ctx)) {
2440 /* If we aren't performing a substitution, treat a newline as a
2441 * command separator. */
2442 if (end_trigger != '\0' && ch == '\n')
2443 done_pipe(ctx, PIPE_SEQ);
2445 if (ch == end_trigger && !dest->quote && ctx->w == RES_NONE) {
2446 debug_printf("leaving parse_stream (triggered)\n");
2453 if (dest->length == 0 && !dest->quote) {
2456 if (ch == EOF || ch == '\n')
2461 b_addqchr(dest, ch, dest->quote);
2469 b_addqchr(dest, '\\', dest->quote);
2470 b_addqchr(dest, b_getch(input), dest->quote);
2473 if (handle_dollar(dest, ctx, input) != 0) return 1;
2478 ch = b_getch(input);
2479 if (ch == EOF || ch == '\'')
2490 dest->quote = !dest->quote;
2493 process_command_subs(dest, ctx, input, '`');
2496 redir_fd = redirect_opt_num(dest);
2497 done_word(dest, ctx);
2498 redir_style = REDIRECT_OVERWRITE;
2500 redir_style = REDIRECT_APPEND;
2502 } else if (next == '(') {
2503 syntax(); /* until we support >(list) Process Substitution */
2506 setup_redirect(ctx, redir_fd, redir_style, input);
2509 redir_fd = redirect_opt_num(dest);
2510 done_word(dest, ctx);
2511 redir_style = REDIRECT_INPUT;
2513 redir_style = REDIRECT_HEREIS;
2515 } else if (next == '>') {
2516 redir_style = REDIRECT_IO;
2518 } else if (next == '(') {
2519 syntax(); /* until we support <(list) Process Substitution */
2522 setup_redirect(ctx, redir_fd, redir_style, input);
2525 done_word(dest, ctx);
2526 done_pipe(ctx, PIPE_SEQ);
2529 done_word(dest, ctx);
2532 done_pipe(ctx, PIPE_AND);
2534 done_pipe(ctx, PIPE_BG);
2538 done_word(dest, ctx);
2541 done_pipe(ctx, PIPE_OR);
2543 /* we could pick up a file descriptor choice here
2544 * with redirect_opt_num(), but bash doesn't do it.
2545 * "echo foo 2| cat" yields "foo 2". */
2551 if (parse_group(dest, ctx, input, ch) != 0)
2556 syntax(); /* Proper use of this character caught by end_trigger */
2559 syntax(); /* this is really an internal logic error */
2563 /* complain if quote? No, maybe we just finished a command substitution
2564 * that was quoted. Example:
2565 * $ echo "`cat foo` plus more"
2566 * and we just got the EOF generated by the subshell that ran "cat foo"
2567 * The only real complaint is if we got an EOF when end_trigger != '\0',
2568 * that is, we were really supposed to get end_trigger, and never got
2569 * one before the EOF. Can't use the standard "syntax error" return code,
2570 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
2571 debug_printf("leaving parse_stream (EOF)\n");
2572 if (end_trigger != '\0')
2577 static void mapset(const char *set, int code)
2580 map[(unsigned char)*set++] = code;
2583 static void update_ifs_map(void)
2585 /* char *ifs and char map[256] are both globals. */
2586 ifs = getenv("IFS");
2587 if (ifs == NULL) ifs = " \t\n";
2588 /* Precompute a list of 'flow through' behavior so it can be treated
2589 * quickly up front. Computation is necessary because of IFS.
2590 * Special case handling of IFS == " \t\n" is not implemented.
2591 * The map[] array only really needs two bits each, and on most machines
2592 * that would be faster because of the reduced L1 cache footprint.
2594 memset(map, 0, sizeof(map)); /* most characters flow through always */
2595 mapset("\\$'\"`", 3); /* never flow through */
2596 mapset("<>;&|(){}#", 1); /* flow through if quoted */
2597 mapset(ifs, 2); /* also flow through if quoted */
2600 /* most recursion does not come through here, the exception is
2601 * from builtin_source() */
2602 int parse_stream_outer(struct in_str *inp, int flag)
2604 struct p_context ctx;
2605 o_string temp = NULL_O_STRING;
2609 initialize_context(&ctx);
2611 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
2612 inp->promptmode = 1;
2613 rcode = parse_stream(&temp, &ctx, inp, '\n');
2614 if (rcode != 1 && ctx.old_flag != 0) {
2617 if (rcode != 1 && ctx.old_flag == 0) {
2618 done_word(&temp, &ctx);
2619 done_pipe(&ctx, PIPE_SEQ);
2620 run_list(ctx.list_head);
2622 if (ctx.old_flag != 0) {
2629 free_pipe_list(ctx.list_head,0);
2632 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
2636 static int parse_string_outer(const char *s, int flag)
2638 struct in_str input;
2639 setup_string_in_str(&input, s);
2640 return parse_stream_outer(&input, flag);
2643 static int parse_file_outer(FILE *f)
2646 struct in_str input;
2647 setup_file_in_str(&input, f);
2648 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
2652 /* Make sure we have a controlling tty. If we get started under a job
2653 * aware app (like bash for example), make sure we are now in charge so
2654 * we don't fight over who gets the foreground */
2655 static void setup_job_control(void)
2657 /*static --why?? */ pid_t shell_pgrp;
2659 /* Loop until we are in the foreground. */
2660 while (tcgetpgrp(shell_terminal) != (shell_pgrp = getpgrp()))
2661 kill(- shell_pgrp, SIGTTIN);
2663 /* Ignore interactive and job-control signals. */
2664 signal(SIGINT, SIG_IGN);
2665 signal(SIGQUIT, SIG_IGN);
2666 signal(SIGTERM, SIG_IGN);
2667 signal(SIGTSTP, SIG_IGN);
2668 signal(SIGTTIN, SIG_IGN);
2669 signal(SIGTTOU, SIG_IGN);
2670 signal(SIGCHLD, SIG_IGN);
2672 /* Put ourselves in our own process group. */
2674 shell_pgrp = getpid();
2675 setpgid(shell_pgrp, shell_pgrp);
2677 /* Grab control of the terminal. */
2678 tcsetpgrp(shell_terminal, shell_pgrp);
2681 int hush_main(int argc, char **argv);
2682 int hush_main(int argc, char **argv)
2688 #if ENABLE_FEATURE_EDITING
2689 line_input_state = new_line_input_t(FOR_SHELL);
2692 /* XXX what should these be while sourcing /etc/profile? */
2696 /* (re?) initialize globals. Sometimes hush_main() ends up calling
2697 * hush_main(), therefore we cannot rely on the BSS to zero out this
2698 * stuff. Reset these to 0 every time. */
2700 /* map[] is taken care of with call to update_ifs_map() */
2703 close_me_head = NULL;
2708 /* Initialize some more globals to non-zero values */
2710 if (ENABLE_FEATURE_EDITING)
2711 cmdedit_set_initial_prompt();
2715 /* initialize our shell local variables with the values
2716 * currently living in the environment */
2720 set_local_var(*e++, 2); /* without call putenv() */
2722 last_return_code = EXIT_SUCCESS;
2724 if (argv[0] && argv[0][0] == '-') {
2725 debug_printf("\nsourcing /etc/profile\n");
2726 input = fopen("/etc/profile", "r");
2727 if (input != NULL) {
2728 mark_open(fileno(input));
2729 parse_file_outer(input);
2730 mark_closed(fileno(input));
2736 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
2739 global_argv = argv+optind;
2740 global_argc = argc-optind;
2741 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
2751 fprintf(stderr, "Usage: sh [FILE]...\n"
2752 " or: sh -c command [args]...\n\n");
2759 /* A shell is interactive if the '-i' flag was given, or if all of
2760 * the following conditions are met:
2762 * no arguments remaining or the -s flag given
2763 * standard input is a terminal
2764 * standard output is a terminal
2765 * Refer to Posix.2, the description of the 'sh' utility. */
2766 if (argv[optind] == NULL && input == stdin
2767 && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
2772 debug_printf("\ninteractive=%d\n", interactive);
2774 /* Looks like they want an interactive shell */
2775 #if !ENABLE_FEATURE_SH_EXTRA_QUIET
2776 printf( "\n\n%s hush - the humble shell v0.01 (testing)\n",
2778 printf( "Enter 'help' for a list of built-in commands.\n\n");
2780 setup_job_control();
2783 if (argv[optind] == NULL) {
2784 opt = parse_file_outer(stdin);
2788 debug_printf("\nrunning script '%s'\n", argv[optind]);
2789 global_argv = argv + optind;
2790 global_argc = argc - optind;
2791 input = xfopen(argv[optind], "r");
2792 opt = parse_file_outer(input);
2794 #if ENABLE_FEATURE_CLEAN_UP
2796 if (cwd != bb_msg_unknown)
2799 struct variables *cur, *tmp;
2800 for (cur = top_vars; cur; cur = tmp) {
2802 if (!cur->flg_read_only) {
2803 free((char*)cur->name);
2804 free((char*)cur->value);
2812 return opt ? opt : last_return_code;
2815 static char *insert_var_value(char *inp)
2817 int res_str_len = 0;
2820 char *p, *res_str = NULL;
2823 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
2826 res_str = xrealloc(res_str, (res_str_len + len));
2827 strncpy((res_str + res_str_len), inp, len);
2831 p = strchr(inp, SPECIAL_VAR_SYMBOL);
2833 p1 = lookup_param(inp);
2835 len = res_str_len + strlen(p1);
2836 res_str = xrealloc(res_str, (1 + len));
2837 strcpy((res_str + res_str_len), p1);
2840 *p = SPECIAL_VAR_SYMBOL;
2845 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
2846 strcpy((res_str + res_str_len), inp);
2847 while ((p = strchr(res_str, '\n'))) {
2851 return (res_str == NULL) ? inp : res_str;
2854 static char **make_list_in(char **inp, char *name)
2857 int name_len = strlen(name);
2862 /* create list of variable values */
2863 list = xmalloc(sizeof(*list));
2864 for (i = 0; inp[i]; i++) {
2865 p3 = insert_var_value(inp[i]);
2872 p2 = strchr(p1, ' ');
2879 /* we use n + 2 in realloc for list, because we add
2880 * new element and then we will add NULL element */
2881 list = xrealloc(list, sizeof(*list) * (n + 2));
2882 list[n] = xmalloc(2 + name_len + len);
2883 strcpy(list[n], name);
2884 strcat(list[n], "=");
2885 strncat(list[n], p1, len);
2886 list[n++][name_len + len + 1] = '\0';
2889 if (p3 != inp[i]) free(p3);
2895 /* Make new string for parser */
2896 static char* make_string(char ** inp)
2903 for (n = 0; inp[n]; n++) {
2904 p = insert_var_value(inp[n]);
2905 str = xrealloc(str, (len + strlen(p)));
2912 len = strlen(str) + 3;
2913 if (p != inp[n]) free(p);