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.
82 #include <glob.h> /* glob, of course */
83 #include <getopt.h> /* should be pretty obvious */
85 //#include <sys/wait.h>
88 /* #include <dmalloc.h> */
89 /* #define DEBUG_SHELL */
92 #define SPECIAL_VAR_SYMBOL 03
93 #define FLAG_EXIT_FROM_LOOP 1
94 #define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
95 #define FLAG_REPARSING (1 << 2) /* >=2nd pass */
99 REDIRECT_OVERWRITE = 2,
105 /* The descrip member of this structure is only used to make debugging
107 static const struct {int mode; int default_fd; const char *descrip;} redir_table[] = {
109 { O_RDONLY, 0, "<" },
110 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
111 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
112 { O_RDONLY, -1, "<<" },
123 /* might eventually control execution */
140 #define FLAG_END (1<<RES_NONE)
141 #define FLAG_IF (1<<RES_IF)
142 #define FLAG_THEN (1<<RES_THEN)
143 #define FLAG_ELIF (1<<RES_ELIF)
144 #define FLAG_ELSE (1<<RES_ELSE)
145 #define FLAG_FI (1<<RES_FI)
146 #define FLAG_FOR (1<<RES_FOR)
147 #define FLAG_WHILE (1<<RES_WHILE)
148 #define FLAG_UNTIL (1<<RES_UNTIL)
149 #define FLAG_DO (1<<RES_DO)
150 #define FLAG_DONE (1<<RES_DONE)
151 #define FLAG_IN (1<<RES_IN)
152 #define FLAG_START (1<<RES_XXXX)
154 /* This holds pointers to the various results of parsing */
156 struct child_prog *child;
157 struct pipe *list_head;
159 struct redir_struct *pending_redirect;
161 int old_flag; /* for figuring out valid reserved words */
162 struct p_context *stack;
163 int type; /* define type of parser : ";$" common or special symbol */
164 /* How about quoting status? */
167 struct redir_struct {
168 redir_type type; /* type of redirection */
169 int fd; /* file descriptor being redirected */
170 int dup; /* -1, or file descriptor being duplicated */
171 struct redir_struct *next; /* pointer to the next redirect in the list */
172 glob_t word; /* *word.gl_pathv is the filename */
176 pid_t pid; /* 0 if exited */
177 char **argv; /* program name and arguments */
178 struct pipe *group; /* if non-NULL, first in group or subshell */
179 int subshell; /* flag, non-zero if group must be forked */
180 struct redir_struct *redirects; /* I/O redirections */
181 glob_t glob_result; /* result of parameter globbing */
182 int is_stopped; /* is the program currently running? */
183 struct pipe *family; /* pointer back to the child's parent pipe */
184 int sp; /* number of SPECIAL_VAR_SYMBOL */
189 int jobid; /* job number */
190 int num_progs; /* total number of programs in job */
191 int running_progs; /* number of programs running */
192 char *text; /* name of job */
193 char *cmdbuf; /* buffer various argv's point into */
194 pid_t pgrp; /* process group ID for the job */
195 struct child_prog *progs; /* array of commands in pipe */
196 struct pipe *next; /* to track background commands */
197 int stopped_progs; /* number of programs alive, but stopped */
198 int job_context; /* bitmask defining current context */
199 pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
200 reserved_style r_mode; /* supports if, for, while, until */
205 struct close_me *next;
213 struct variables *next;
216 /* globals, connect us to the outside world
217 * the first three support $?, $#, and $1 */
218 static char **global_argv;
219 static int global_argc;
220 static int last_return_code;
221 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
223 /* "globals" within this file */
225 static unsigned char map[256];
226 static int fake_mode;
227 static int interactive;
228 static struct close_me *close_me_head;
229 static const char *cwd;
230 static struct pipe *job_list;
231 static unsigned last_bg_pid;
232 static int last_jobid;
233 static unsigned shell_terminal;
236 static struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
237 static struct variables *top_vars = &shell_ver;
240 #define B_CHUNK (100)
250 #define NULL_O_STRING {NULL,0,0,0,0}
251 /* used for initialization:
252 o_string foo = NULL_O_STRING; */
254 /* I can almost use ordinary FILE *. Is open_memstream() universally
255 * available? Where is it documented? */
262 int (*get) (struct in_str *);
263 int (*peek) (struct in_str *);
265 #define b_getch(input) ((input)->get(input))
266 #define b_peek(input) ((input)->peek(input))
268 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
270 struct built_in_command {
271 const char *cmd; /* name */
272 const char *descr; /* description */
273 int (*function) (struct child_prog *); /* function ptr */
276 /* belongs in busybox.h */
277 static int max(int a, int b)
282 /* This should be in utility.c */
284 static void debug_printf(const char *format, ...)
287 va_start(args, format);
288 vfprintf(stderr, format, args);
291 /* broken, of course, but OK for testing */
292 static char *indenter(int i)
294 static char blanks[] = " ";
295 return &blanks[sizeof(blanks)-i-1];
298 #define debug_printf(...) do {;} while (0);
300 #define final_printf debug_printf
302 static void __syntax(const char *file, int line)
304 bb_error_msg("syntax error %s:%d", file, line);
306 // NB: was __FILE__, but that produces full path sometimess, so...
307 #define syntax() __syntax("hush.c", __LINE__)
309 /* Index of subroutines: */
310 /* function prototypes for builtins */
311 static int builtin_cd(struct child_prog *child);
312 static int builtin_env(struct child_prog *child);
313 static int builtin_eval(struct child_prog *child);
314 static int builtin_exec(struct child_prog *child);
315 static int builtin_exit(struct child_prog *child);
316 static int builtin_export(struct child_prog *child);
317 static int builtin_fg_bg(struct child_prog *child);
318 static int builtin_help(struct child_prog *child);
319 static int builtin_jobs(struct child_prog *child);
320 static int builtin_pwd(struct child_prog *child);
321 static int builtin_read(struct child_prog *child);
322 static int builtin_set(struct child_prog *child);
323 static int builtin_shift(struct child_prog *child);
324 static int builtin_source(struct child_prog *child);
325 static int builtin_umask(struct child_prog *child);
326 static int builtin_unset(struct child_prog *child);
327 static int builtin_not_written(struct child_prog *child);
328 /* o_string manipulation: */
329 static int b_check_space(o_string *o, int len);
330 static int b_addchr(o_string *o, int ch);
331 static void b_reset(o_string *o);
332 static int b_addqchr(o_string *o, int ch, int quote);
333 static int b_adduint(o_string *o, unsigned i);
334 /* in_str manipulations: */
335 static int static_get(struct in_str *i);
336 static int static_peek(struct in_str *i);
337 static int file_get(struct in_str *i);
338 static int file_peek(struct in_str *i);
339 static void setup_file_in_str(struct in_str *i, FILE *f);
340 static void setup_string_in_str(struct in_str *i, const char *s);
341 /* close_me manipulations: */
342 static void mark_open(int fd);
343 static void mark_closed(int fd);
344 static void close_all(void);
345 /* "run" the final data structures: */
346 static int free_pipe_list(struct pipe *head, int indent);
347 static int free_pipe(struct pipe *pi, int indent);
348 /* really run the final data structures: */
349 static int setup_redirects(struct child_prog *prog, int squirrel[]);
350 static int run_list_real(struct pipe *pi);
351 static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN;
352 static int run_pipe_real(struct pipe *pi);
353 /* extended glob support: */
354 static int globhack(const char *src, int flags, glob_t *pglob);
355 static int glob_needed(const char *s);
356 static int xglob(o_string *dest, int flags, glob_t *pglob);
357 /* variable assignment: */
358 static int is_assignment(const char *s);
359 /* data structure manipulation: */
360 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
361 static void initialize_context(struct p_context *ctx);
362 static int done_word(o_string *dest, struct p_context *ctx);
363 static int done_command(struct p_context *ctx);
364 static int done_pipe(struct p_context *ctx, pipe_style type);
365 /* primary string parsing: */
366 static int redirect_dup_num(struct in_str *input);
367 static int redirect_opt_num(o_string *o);
368 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
369 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
370 static const char *lookup_param(const char *src);
371 static char *make_string(char **inp);
372 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
373 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
374 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
376 static int parse_stream_outer(struct in_str *inp, int flag);
377 static int parse_string_outer(const char *s, int flag);
378 static int parse_file_outer(FILE *f);
379 /* job management: */
380 static int checkjobs(struct pipe* fg_pipe);
381 static void insert_bg_job(struct pipe *pi);
382 static void remove_bg_job(struct pipe *pi);
383 /* local variable support */
384 static char **make_list_in(char **inp, char *name);
385 static char *insert_var_value(char *inp);
386 static const char *get_local_var(const char *var);
387 static void unset_local_var(const char *name);
388 static int set_local_var(const char *s, int flg_export);
390 /* Table of built-in functions. They can be forked or not, depending on
391 * context: within pipes, they fork. As simple commands, they do not.
392 * When used in non-forking context, they can change global variables
393 * in the parent shell process. If forked, of course they cannot.
394 * For example, 'unset foo | whatever' will parse and run, but foo will
395 * still be set at the end. */
396 static const struct built_in_command bltins[] = {
397 { "bg", "Resume a job in the background", builtin_fg_bg },
398 { "break", "Exit for, while or until loop", builtin_not_written },
399 { "cd", "Change working directory", builtin_cd },
400 { "continue", "Continue for, while or until loop", builtin_not_written },
401 { "env", "Print all environment variables", builtin_env },
402 { "eval", "Construct and run shell command", builtin_eval },
403 { "exec", "Exec command, replacing this shell with the exec'd process",
405 { "exit", "Exit from shell()", builtin_exit },
406 { "export", "Set environment variable", builtin_export },
407 { "fg", "Bring job into the foreground", builtin_fg_bg },
408 { "jobs", "Lists the active jobs", builtin_jobs },
409 { "pwd", "Print current directory", builtin_pwd },
410 { "read", "Input environment variable", builtin_read },
411 { "return", "Return from a function", builtin_not_written },
412 { "set", "Set/unset shell local variables", builtin_set },
413 { "shift", "Shift positional parameters", builtin_shift },
414 { "trap", "Trap signals", builtin_not_written },
415 { "ulimit","Controls resource limits", builtin_not_written },
416 { "umask","Sets file creation mask", builtin_umask },
417 { "unset", "Unset environment variable", builtin_unset },
418 { ".", "Source-in and run commands in a file", builtin_source },
419 { "help", "List shell built-in commands", builtin_help },
423 static const char *set_cwd(void)
425 if (cwd == bb_msg_unknown)
426 cwd = NULL; /* xgetcwd(arg) called free(arg) */
427 cwd = xgetcwd((char *)cwd);
429 cwd = bb_msg_unknown;
433 /* built-in 'eval' handler */
434 static int builtin_eval(struct child_prog *child)
437 int rcode = EXIT_SUCCESS;
439 if (child->argv[1]) {
440 str = make_string(child->argv + 1);
441 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
442 FLAG_PARSE_SEMICOLON);
444 rcode = last_return_code;
449 /* built-in 'cd <path>' handler */
450 static int builtin_cd(struct child_prog *child)
453 if (child->argv[1] == NULL)
454 newdir = getenv("HOME");
456 newdir = child->argv[1];
458 printf("cd: %s: %s\n", newdir, strerror(errno));
465 /* built-in 'env' handler */
466 static int builtin_env(struct child_prog *dummy ATTRIBUTE_UNUSED)
469 if (e == NULL) return EXIT_FAILURE;
476 /* built-in 'exec' handler */
477 static int builtin_exec(struct child_prog *child)
479 if (child->argv[1] == NULL)
480 return EXIT_SUCCESS; /* Really? */
486 /* built-in 'exit' handler */
487 static int builtin_exit(struct child_prog *child)
489 if (child->argv[1] == NULL)
490 exit(last_return_code);
491 exit (atoi(child->argv[1]));
494 /* built-in 'export VAR=value' handler */
495 static int builtin_export(struct child_prog *child)
498 char *name = child->argv[1];
501 return builtin_env(child);
507 const char *value = strchr(name, '=');
511 /* They are exporting something without an =VALUE */
513 value = get_local_var(name);
515 size_t ln = strlen(name);
517 tmp = realloc(name, ln+strlen(value)+2);
521 sprintf(tmp+ln, "=%s", value);
525 /* bash does not return an error when trying to export
526 * an undefined variable. Do likewise. */
532 bb_perror_msg("export");
534 res = set_local_var(name, 1);
541 /* built-in 'fg' and 'bg' handler */
542 static int builtin_fg_bg(struct child_prog *child)
545 struct pipe *pi = NULL;
549 /* If they gave us no args, assume they want the last backgrounded task */
550 if (!child->argv[1]) {
551 for (pi = job_list; pi; pi = pi->next) {
552 if (pi->jobid == last_jobid) {
557 bb_error_msg("%s: no current job", child->argv[0]);
561 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
562 bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
565 for (pi = job_list; pi; pi = pi->next) {
566 if (pi->jobid == jobnum) {
571 bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
576 if (*child->argv[0] == 'f') {
577 /* Put the job into the foreground. */
578 tcsetpgrp(shell_terminal, pi->pgrp);
581 /* Restart the processes in the job */
582 for (i = 0; i < pi->num_progs; i++)
583 pi->progs[i].is_stopped = 0;
585 if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
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);
631 /* built-in 'pwd' handler */
632 static int builtin_pwd(struct child_prog *dummy ATTRIBUTE_UNUSED)
638 /* built-in 'read VAR' handler */
639 static int builtin_read(struct child_prog *child)
643 if (child->argv[1]) {
647 string[0] = '\0'; /* In case stdin has only EOF */
649 fgets(string, sizeof(string), stdin);
651 var = malloc(strlen(child->argv[1]) + strlen(string) + 2);
653 sprintf(var, "%s=%s", child->argv[1], string);
654 res = set_local_var(var, 0);
658 bb_perror_msg("read");
659 free(var); /* So not move up to avoid breaking errno */
662 do res = getchar(); while (res != '\n' && res != EOF);
666 /* built-in 'set VAR=value' handler */
667 static int builtin_set(struct child_prog *child)
669 char *temp = child->argv[1];
673 for (e = top_vars; e; e = e->next)
674 printf("%s=%s\n", e->name, e->value);
676 set_local_var(temp, 0);
682 /* Built-in 'shift' handler */
683 static int builtin_shift(struct child_prog *child)
686 if (child->argv[1]) {
687 n = atoi(child->argv[1]);
689 if (n >= 0 && n < global_argc) {
690 /* XXX This probably breaks $0 */
699 /* Built-in '.' handler (read-in and execute commands from file) */
700 static int builtin_source(struct child_prog *child)
705 if (child->argv[1] == NULL)
708 /* XXX search through $PATH is missing */
709 input = fopen(child->argv[1], "r");
711 bb_error_msg("cannot open '%s'", child->argv[1]);
715 /* Now run the file */
716 /* XXX argv and argc are broken; need to save old global_argv
717 * (pointer only is OK!) on this stack frame,
718 * set global_argv=child->argv+1, recurse, and restore. */
719 mark_open(fileno(input));
720 status = parse_file_outer(input);
721 mark_closed(fileno(input));
726 static int builtin_umask(struct child_prog *child)
729 const char *arg = child->argv[1];
732 new_umask = strtoul(arg, &end, 8);
733 if (*end != '\0' || end == arg) {
737 new_umask = umask(0);
738 printf("%.3o\n", (unsigned) new_umask);
744 /* built-in 'unset VAR' handler */
745 static int builtin_unset(struct child_prog *child)
747 /* bash returned already true */
748 unset_local_var(child->argv[1]);
752 static int builtin_not_written(struct child_prog *child)
754 printf("builtin_%s not written\n", child->argv[0]);
758 static int b_check_space(o_string *o, int len)
760 /* It would be easy to drop a more restrictive policy
761 * in here, such as setting a maximum string length */
762 if (o->length + len > o->maxlen) {
763 char *old_data = o->data;
764 /* assert (data == NULL || o->maxlen != 0); */
765 o->maxlen += max(2*len, B_CHUNK);
766 o->data = realloc(o->data, 1 + o->maxlen);
767 if (o->data == NULL) {
771 return o->data == NULL;
774 static int b_addchr(o_string *o, int ch)
776 debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
777 if (b_check_space(o, 1))
779 o->data[o->length] = ch;
781 o->data[o->length] = '\0';
785 static void b_reset(o_string *o)
793 static void b_free(o_string *o)
801 /* My analysis of quoting semantics tells me that state information
802 * is associated with a destination, not a source.
804 static int b_addqchr(o_string *o, int ch, int quote)
806 if (quote && strchr("*?[\\",ch)) {
808 rc = b_addchr(o, '\\');
812 return b_addchr(o, ch);
815 /* belongs in utility.c */
816 static char *simple_itoa(unsigned i)
818 static char local[sizeof(int)*3 + 2];
819 char *p = &local[sizeof(int)*3 + 2 - 1];
828 static int b_adduint(o_string *o, unsigned i)
831 char *p = simple_itoa(i);
832 /* no escape checking necessary */
833 do r = b_addchr(o, *p++); while (r==0 && *p);
837 static int static_get(struct in_str *i)
840 if (ch == '\0') return EOF;
844 static int static_peek(struct in_str *i)
849 static void cmdedit_set_initial_prompt(void)
851 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
860 static void setup_prompt_string(int promptmode, char **prompt_str)
862 debug_printf("setup_prompt_string %d ",promptmode);
863 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
864 /* Set up the prompt */
865 if (promptmode == 1) {
867 PS1 = xmalloc(strlen(cwd)+4);
868 sprintf(PS1, "%s %s", cwd, (geteuid() != 0) ? "$ " : "# ");
874 *prompt_str = (promptmode == 1) ? PS1 : PS2;
876 debug_printf("result %s\n", *prompt_str);
879 #if ENABLE_FEATURE_EDITING
880 static line_input_t *line_input_state;
883 static void get_user_input(struct in_str *i)
886 static char the_command[BUFSIZ];
888 setup_prompt_string(i->promptmode, &prompt_str);
889 #if ENABLE_FEATURE_EDITING
891 ** enable command line editing only while a command line
892 ** is actually being read; otherwise, we'll end up bequeathing
893 ** atexit() handlers and other unwanted stuff to our
894 ** child processes (rob@sysgo.de)
896 read_line_input(prompt_str, the_command, BUFSIZ, line_input_state);
898 fputs(prompt_str, stdout);
900 the_command[0] = fgetc(i->file);
901 the_command[1] = '\0';
907 /* This is the magic location that prints prompts
908 * and gets data back from the user */
909 static int file_get(struct in_str *i)
914 /* If there is data waiting, eat it up */
918 /* need to double check i->file because we might be doing something
919 * more complicated by now, like sourcing or substituting. */
920 if (i->__promptme && interactive && i->file == stdin) {
921 while (!i->p || !(interactive && strlen(i->p))) {
933 debug_printf("b_getch: got a %d\n", ch);
940 /* All the callers guarantee this routine will never be
941 * used right after a newline, so prompting is not needed.
943 static int file_peek(struct in_str *i)
948 i->peek_buf[0] = fgetc(i->file);
949 i->peek_buf[1] = '\0';
951 debug_printf("b_peek: got a %d\n", *i->p);
956 static void setup_file_in_str(struct in_str *i, FILE *f)
966 static void setup_string_in_str(struct in_str *i, const char *s)
968 i->peek = static_peek;
975 static void mark_open(int fd)
977 struct close_me *new = xmalloc(sizeof(struct close_me));
979 new->next = close_me_head;
983 static void mark_closed(int fd)
985 struct close_me *tmp;
986 if (close_me_head == NULL || close_me_head->fd != fd)
987 bb_error_msg_and_die("corrupt close_me");
989 close_me_head = close_me_head->next;
993 static void close_all(void)
996 for (c = close_me_head; c; c = c->next) {
999 close_me_head = NULL;
1002 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1003 * and stderr if they are redirected. */
1004 static int setup_redirects(struct child_prog *prog, int squirrel[])
1007 struct redir_struct *redir;
1009 for (redir = prog->redirects; redir; redir = redir->next) {
1010 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1011 /* something went wrong in the parse. Pretend it didn't happen */
1014 if (redir->dup == -1) {
1015 mode = redir_table[redir->type].mode;
1016 openfd = open(redir->word.gl_pathv[0], mode, 0666);
1018 /* this could get lost if stderr has been redirected, but
1019 bash and ash both lose it as well (though zsh doesn't!) */
1020 bb_perror_msg("error opening %s", redir->word.gl_pathv[0]);
1024 openfd = redir->dup;
1027 if (openfd != redir->fd) {
1028 if (squirrel && redir->fd < 3) {
1029 squirrel[redir->fd] = dup(redir->fd);
1034 dup2(openfd, redir->fd);
1035 if (redir->dup == -1)
1043 static void restore_redirects(int squirrel[])
1046 for (i = 0; i < 3; i++) {
1049 /* No error checking. I sure wouldn't know what
1050 * to do with an error if I found one! */
1058 /* XXX no exit() here. If you don't exec, use _exit instead.
1059 * The at_exit handlers apparently confuse the calling process,
1060 * in particular stdin handling. Not sure why? */
1061 static void pseudo_exec(struct child_prog *child)
1065 const struct built_in_command *x;
1067 for (i = 0; is_assignment(child->argv[i]); i++) {
1068 debug_printf("pid %d environment modification: %s\n",
1069 getpid(), child->argv[i]);
1070 p = insert_var_value(child->argv[i]);
1072 if (p != child->argv[i])
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 #if ENABLE_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; argv_l++, argc_l++)
1119 debug_printf("running applet %s\n", name);
1120 run_applet_by_name(name, argc_l, child->argv);
1123 debug_printf("exec of %s\n", child->argv[0]);
1124 execvp(child->argv[0], child->argv);
1125 bb_perror_msg("cannot exec: %s", child->argv[0]);
1127 } else if (child->group) {
1128 debug_printf("runtime nesting to group\n");
1129 interactive = 0; /* crucial!!!! */
1130 rcode = run_list_real(child->group);
1131 /* OK to leak memory by not calling free_pipe_list,
1132 * since this process is about to exit */
1135 /* Can happen. See what bash does with ">foo" by itself. */
1136 debug_printf("trying to pseudo_exec null command\n");
1137 _exit(EXIT_SUCCESS);
1141 static void insert_bg_job(struct pipe *pi)
1143 struct pipe *thejob;
1145 /* Linear search for the ID of the job to use */
1147 for (thejob = job_list; thejob; thejob = thejob->next)
1148 if (thejob->jobid >= pi->jobid)
1149 pi->jobid = thejob->jobid + 1;
1151 /* add thejob to the list of running jobs */
1153 thejob = job_list = xmalloc(sizeof(*thejob));
1155 for (thejob = job_list; thejob->next; thejob = thejob->next)
1157 thejob->next = xmalloc(sizeof(*thejob));
1158 thejob = thejob->next;
1161 /* physically copy the struct job */
1162 memcpy(thejob, pi, sizeof(struct pipe));
1163 thejob->next = NULL;
1164 thejob->running_progs = thejob->num_progs;
1165 thejob->stopped_progs = 0;
1166 thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1168 //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0])
1170 char *bar = thejob->text;
1171 char **foo = pi->progs[0].argv;
1174 bar += sprintf(bar, "%s ", *foo++);
1177 /* we don't wait for background thejobs to return -- append it
1178 to the list of backgrounded thejobs and leave it alone */
1179 printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1180 last_bg_pid = thejob->progs[0].pid;
1181 last_jobid = thejob->jobid;
1184 /* remove a backgrounded job */
1185 static void remove_bg_job(struct pipe *pi)
1187 struct pipe *prev_pipe;
1189 if (pi == job_list) {
1190 job_list = pi->next;
1192 prev_pipe = job_list;
1193 while (prev_pipe->next != pi)
1194 prev_pipe = prev_pipe->next;
1195 prev_pipe->next = pi->next;
1198 last_jobid = job_list->jobid;
1202 pi->stopped_progs = 0;
1207 /* Checks to see if any processes have exited -- if they
1208 have, figure out why and see if a job has completed */
1209 static int checkjobs(struct pipe* fg_pipe)
1217 attributes = WUNTRACED;
1218 if (fg_pipe == NULL) {
1219 attributes |= WNOHANG;
1222 while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1225 for (i = 0; i < fg_pipe->num_progs; i++) {
1226 if (fg_pipe->progs[i].pid == childpid) {
1227 if (i == fg_pipe->num_progs-1)
1228 rcode = WEXITSTATUS(status);
1229 fg_pipe->num_progs--;
1235 for (pi = job_list; pi; pi = pi->next) {
1237 while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1240 if (prognum < pi->num_progs)
1245 debug_printf("checkjobs: pid %d was not in our list!\n",
1250 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1252 pi->running_progs--;
1253 pi->progs[prognum].pid = 0;
1255 if (!pi->running_progs) {
1256 printf(JOB_STATUS_FORMAT, pi->jobid,
1262 pi->stopped_progs++;
1263 pi->progs[prognum].is_stopped = 1;
1267 if (childpid == -1 && errno != ECHILD)
1268 bb_perror_msg("waitpid");
1270 /* move the shell to the foreground */
1271 //if (interactive && tcsetpgrp(shell_terminal, getpgid(0)))
1272 // bb_perror_msg("tcsetpgrp-2");
1276 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1277 * to finish. See checkjobs().
1279 * return code is normally -1, when the caller has to wait for children
1280 * to finish to determine the exit status of the pipe. If the pipe
1281 * is a simple builtin command, however, the action is done by the
1282 * time run_pipe_real returns, and the exit code is provided as the
1285 * The input of the pipe is always stdin, the output is always
1286 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1287 * because it tries to avoid running the command substitution in
1288 * subshell, when that is in fact necessary. The subshell process
1289 * now has its stdout directed to the input of the appropriate pipe,
1290 * so this routine is noticeably simpler.
1292 static int run_pipe_real(struct pipe *pi)
1295 int nextin, nextout;
1296 int pipefds[2]; /* pipefds[0] is for reading */
1297 struct child_prog *child;
1298 const struct built_in_command *x;
1304 /* Check if this is a simple builtin (not part of a pipe).
1305 * Builtins within pipes have to fork anyway, and are handled in
1306 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1308 child = &(pi->progs[0]);
1309 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1310 int squirrel[] = { -1, -1, -1 };
1312 debug_printf("non-subshell grouping\n");
1313 setup_redirects(child, squirrel);
1314 /* XXX could we merge code with following builtin case,
1315 * by creating a pseudo builtin that calls run_list_real? */
1316 rcode = run_list_real(child->group);
1317 restore_redirects(squirrel);
1319 } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1320 for (i = 0; is_assignment(child->argv[i]); i++)
1322 if (i != 0 && child->argv[i] == NULL) {
1323 /* assignments, but no command: set the local environment */
1324 for (i = 0; child->argv[i] != NULL; i++) {
1325 /* Ok, this case is tricky. We have to decide if this is a
1326 * local variable, or an already exported variable. If it is
1327 * already exported, we have to export the new value. If it is
1328 * not exported, we need only set this as a local variable.
1329 * This junk is all to decide whether or not to export this
1333 name = xstrdup(child->argv[i]);
1334 debug_printf("Local environment set: %s\n", name);
1335 value = strchr(name, '=');
1338 if (get_local_var(name)) {
1342 p = insert_var_value(child->argv[i]);
1343 set_local_var(p, export_me);
1344 if (p != child->argv[i])
1347 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1349 for (i = 0; is_assignment(child->argv[i]); i++) {
1350 p = insert_var_value(child->argv[i]);
1352 if (p != child->argv[i]) {
1360 str = make_string((child->argv + i));
1361 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1363 return last_return_code;
1365 for (x = bltins; x->cmd; x++) {
1366 if (strcmp(child->argv[i], x->cmd) == 0 ) {
1367 int squirrel[] = { -1, -1, -1 };
1369 if (x->function == builtin_exec && child->argv[i+1] == NULL) {
1370 debug_printf("magic exec\n");
1371 setup_redirects(child,NULL);
1372 return EXIT_SUCCESS;
1374 debug_printf("builtin inline %s\n", child->argv[0]);
1375 /* XXX setup_redirects acts on file descriptors, not FILEs.
1376 * This is perfect for work that comes after exec().
1377 * Is it really safe for inline use? Experimentally,
1378 * things seem to work with glibc. */
1379 setup_redirects(child, squirrel);
1380 child->argv += i; /* XXX horrible hack */
1381 rcode = x->function(child);
1382 child->argv -= i; /* XXX restore hack so free() can work right */
1383 restore_redirects(squirrel);
1389 for (i = 0; i < pi->num_progs; i++) {
1390 child = &(pi->progs[i]);
1392 /* pipes are inserted between pairs of commands */
1393 if ((i + 1) < pi->num_progs) {
1394 if (pipe(pipefds) < 0)
1395 bb_perror_msg_and_die("pipe");
1396 nextout = pipefds[1];
1402 /* XXX test for failed fork()? */
1403 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
1404 child->pid = fork();
1406 child->pid = vfork();
1409 /* Set the handling for job control signals back to the default. */
1410 signal(SIGINT, SIG_DFL);
1411 signal(SIGQUIT, SIG_DFL);
1412 signal(SIGTERM, SIG_DFL);
1413 signal(SIGTSTP, SIG_DFL);
1414 signal(SIGTTIN, SIG_DFL);
1415 signal(SIGTTOU, SIG_DFL);
1416 signal(SIGCHLD, SIG_DFL);
1428 if (pipefds[0]!=-1) {
1429 close(pipefds[0]); /* opposite end of our output pipe */
1432 /* Like bash, explicit redirects override pipes,
1433 * and the pipe fd is available for dup'ing. */
1434 setup_redirects(child,NULL);
1436 if (interactive && pi->followup!=PIPE_BG) {
1437 /* If we (the child) win the race, put ourselves in the process
1438 * group whose leader is the first process in this pipe. */
1440 pi->pgrp = getpid();
1442 if (setpgid(0, pi->pgrp) == 0) {
1443 tcsetpgrp(2, pi->pgrp);
1450 /* put our child in the process group whose leader is the
1451 first process in this pipe */
1453 pi->pgrp = child->pid;
1455 /* Don't check for errors. The child may be dead already,
1456 * in which case setpgid returns error code EACCES. */
1457 setpgid(child->pid, pi->pgrp);
1464 /* If there isn't another process, nextin is garbage
1465 but it doesn't matter */
1466 nextin = pipefds[0];
1471 static int run_list_real(struct pipe *pi)
1473 char *save_name = NULL;
1475 char **save_list = NULL;
1479 int rcode = 0, flag_skip = 1;
1480 int flag_restore = 0;
1481 int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
1482 reserved_style rmode, skip_more_in_this_rmode = RES_XXXX;
1483 /* check syntax for "for" */
1484 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1485 if ((rpipe->r_mode == RES_IN || rpipe->r_mode == RES_FOR)
1486 && (rpipe->next == NULL)
1491 if ((rpipe->r_mode == RES_IN && rpipe->next->r_mode == RES_IN && rpipe->next->progs->argv != NULL)
1492 || (rpipe->r_mode == RES_FOR && rpipe->next->r_mode != RES_IN)
1498 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1499 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL
1500 || pi->r_mode == RES_FOR
1509 debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n",
1510 rmode, if_code, next_if_code, skip_more_in_this_rmode);
1511 if (rmode == skip_more_in_this_rmode && flag_skip) {
1512 if (pi->followup == PIPE_SEQ)
1517 skip_more_in_this_rmode = RES_XXXX;
1518 if (rmode == RES_THEN || rmode == RES_ELSE)
1519 if_code = next_if_code;
1520 if (rmode == RES_THEN && if_code)
1522 if (rmode == RES_ELSE && !if_code)
1524 if (rmode == RES_ELIF && !if_code)
1526 if (rmode == RES_FOR && pi->num_progs) {
1528 /* if no variable values after "in" we skip "for" */
1529 if (!pi->next->progs->argv)
1531 /* create list of variable values */
1532 list = make_list_in(pi->next->progs->argv,
1533 pi->progs->argv[0]);
1535 save_name = pi->progs->argv[0];
1536 pi->progs->argv[0] = NULL;
1540 free(pi->progs->argv[0]);
1544 pi->progs->argv[0] = save_name;
1545 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1548 /* insert new value from list for variable */
1549 if (pi->progs->argv[0])
1550 free(pi->progs->argv[0]);
1551 pi->progs->argv[0] = *list++;
1552 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1555 if (rmode == RES_IN)
1557 if (rmode == RES_DO) {
1561 if ((rmode == RES_DONE)) {
1568 if (pi->num_progs == 0)
1570 save_num_progs = pi->num_progs; /* save number of programs */
1571 rcode = run_pipe_real(pi);
1572 debug_printf("run_pipe_real returned %d\n",rcode);
1574 /* We only ran a builtin: rcode was set by the return value
1575 * of run_pipe_real(), and we don't need to wait for anything. */
1576 } else if (pi->followup == PIPE_BG) {
1577 /* XXX check bash's behavior with nontrivial pipes */
1578 /* XXX compute jobid */
1579 /* XXX what does bash do with attempts to background builtins? */
1581 rcode = EXIT_SUCCESS;
1584 /* move the new process group into the foreground */
1585 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1586 bb_perror_msg("tcsetpgrp-3");
1587 rcode = checkjobs(pi);
1588 /* move the shell to the foreground */
1589 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1590 bb_perror_msg("tcsetpgrp-4");
1592 rcode = checkjobs(pi);
1594 debug_printf("checkjobs returned %d\n",rcode);
1596 last_return_code = rcode;
1597 pi->num_progs = save_num_progs; /* restore number of programs */
1598 if ( rmode == RES_IF || rmode == RES_ELIF )
1599 next_if_code = rcode; /* can be overwritten a number of times */
1600 if (rmode == RES_WHILE)
1601 flag_rep = !last_return_code;
1602 if (rmode == RES_UNTIL)
1603 flag_rep = last_return_code;
1604 if ((rcode == EXIT_SUCCESS && pi->followup == PIPE_OR)
1605 || (rcode != EXIT_SUCCESS && pi->followup == PIPE_AND)
1607 skip_more_in_this_rmode = rmode;
1614 /* return code is the exit status of the pipe */
1615 static int free_pipe(struct pipe *pi, int indent)
1618 struct child_prog *child;
1619 struct redir_struct *r, *rnext;
1620 int a, i, ret_code = 0;
1622 if (pi->stopped_progs > 0)
1624 final_printf("%s run pipe: (pid %d)\n", indenter(indent), getpid());
1625 for (i = 0; i < pi->num_progs; i++) {
1626 child = &pi->progs[i];
1627 final_printf("%s command %d:\n", indenter(indent), i);
1629 for (a = 0, p = child->argv; *p; a++, p++) {
1630 final_printf("%s argv[%d] = %s\n", indenter(indent), a, *p);
1632 globfree(&child->glob_result);
1634 } else if (child->group) {
1635 final_printf("%s begin group (subshell:%d)\n", indenter(indent), child->subshell);
1636 ret_code = free_pipe_list(child->group, indent+3);
1637 final_printf("%s end group\n", indenter(indent));
1639 final_printf("%s (nil)\n", indenter(indent));
1641 for (r = child->redirects; r; r = rnext) {
1642 final_printf("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip);
1644 /* guard against the case >$FOO, where foo is unset or blank */
1645 if (r->word.gl_pathv) {
1646 final_printf(" %s\n", *r->word.gl_pathv);
1650 final_printf("&%d\n", r->dup);
1655 child->redirects = NULL;
1657 free(pi->progs); /* children are an array, they get freed all at once */
1662 static int free_pipe_list(struct pipe *head, int indent)
1664 int rcode = 0; /* if list has no members */
1665 struct pipe *pi, *next;
1666 for (pi = head; pi; pi = next) {
1667 final_printf("%s pipe reserved mode %d\n", indenter(indent), pi->r_mode);
1668 rcode = free_pipe(pi, indent);
1669 final_printf("%s pipe followup code %d\n", indenter(indent), pi->followup);
1677 /* Select which version we will use */
1678 static int run_list(struct pipe *pi)
1681 if (fake_mode == 0) {
1682 rcode = run_list_real(pi);
1684 /* free_pipe_list has the side effect of clearing memory
1685 * In the long run that function can be merged with run_list_real,
1686 * but doing that now would hobble the debugging effort. */
1687 free_pipe_list(pi,0);
1691 /* The API for glob is arguably broken. This routine pushes a non-matching
1692 * string into the output structure, removing non-backslashed backslashes.
1693 * If someone can prove me wrong, by performing this function within the
1694 * original glob(3) api, feel free to rewrite this routine into oblivion.
1695 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
1696 * XXX broken if the last character is '\\', check that before calling.
1698 static int globhack(const char *src, int flags, glob_t *pglob)
1703 for (cnt = 1, s = src; s && *s; s++) {
1704 if (*s == '\\') s++;
1708 if (!dest) return GLOB_NOSPACE;
1709 if (!(flags & GLOB_APPEND)) {
1710 pglob->gl_pathv = NULL;
1711 pglob->gl_pathc = 0;
1715 pathc = ++pglob->gl_pathc;
1716 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
1717 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
1718 pglob->gl_pathv[pathc-1] = dest;
1719 pglob->gl_pathv[pathc] = NULL;
1720 for (s = src; s && *s; s++, dest++) {
1721 if (*s == '\\') s++;
1728 /* XXX broken if the last character is '\\', check that before calling */
1729 static int glob_needed(const char *s)
1732 if (*s == '\\') s++;
1733 if (strchr("*[?", *s)) return 1;
1738 static int xglob(o_string *dest, int flags, glob_t *pglob)
1742 /* short-circuit for null word */
1743 /* we can code this better when the debug_printf's are gone */
1744 if (dest->length == 0) {
1745 if (dest->nonnull) {
1746 /* bash man page calls this an "explicit" null */
1747 gr = globhack(dest->data, flags, pglob);
1748 debug_printf("globhack returned %d\n", gr);
1752 } else if (glob_needed(dest->data)) {
1753 gr = glob(dest->data, flags, NULL, pglob);
1754 debug_printf("glob returned %d\n", gr);
1755 if (gr == GLOB_NOMATCH) {
1756 /* quote removal, or more accurately, backslash removal */
1757 gr = globhack(dest->data, flags, pglob);
1758 debug_printf("globhack returned %d\n", gr);
1761 gr = globhack(dest->data, flags, pglob);
1762 debug_printf("globhack returned %d\n", gr);
1764 if (gr == GLOB_NOSPACE)
1765 bb_error_msg_and_die("out of memory during glob");
1766 if (gr != 0) { /* GLOB_ABORTED ? */
1767 bb_error_msg("glob(3) error %d", gr);
1769 /* globprint(glob_target); */
1773 /* This is used to get/check local shell variables */
1774 static const char *get_local_var(const char *s)
1776 struct variables *cur;
1780 for (cur = top_vars; cur; cur = cur->next)
1781 if (strcmp(cur->name, s) == 0)
1786 /* This is used to set local shell variables
1787 flg_export==0 if only local (not exporting) variable
1788 flg_export==1 if "new" exporting environ
1789 flg_export>1 if current startup environ (not call putenv()) */
1790 static int set_local_var(const char *s, int flg_export)
1794 struct variables *cur;
1798 /* Assume when we enter this function that we are already in
1799 * NAME=VALUE format. So the first order of business is to
1800 * split 's' on the '=' into 'name' and 'value' */
1801 value = strchr(name, '=');
1802 if (value == 0 && ++value == 0) {
1808 for (cur = top_vars; cur; cur = cur->next) {
1809 if (strcmp(cur->name, name) == 0)
1814 if (strcmp(cur->value, value) == 0) {
1815 if (flg_export>0 && cur->flg_export == 0)
1816 cur->flg_export = flg_export;
1820 if (cur->flg_read_only) {
1821 bb_error_msg("%s: readonly variable", name);
1824 if (flg_export > 0 || cur->flg_export>1)
1825 cur->flg_export = 1;
1826 free((char*)cur->value);
1828 cur->value = strdup(value);
1832 cur = malloc(sizeof(struct variables));
1836 cur->name = strdup(name);
1841 struct variables *bottom = top_vars;
1842 cur->value = strdup(value);
1844 cur->flg_export = flg_export;
1845 cur->flg_read_only = 0;
1846 while (bottom->next)
1847 bottom = bottom->next;
1853 if (result == 0 && cur->flg_export == 1) {
1855 result = putenv(name);
1858 if (result > 0) /* equivalent to previous set */
1864 static void unset_local_var(const char *name)
1866 struct variables *cur;
1869 for (cur = top_vars; cur; cur = cur->next) {
1870 if (strcmp(cur->name, name) == 0)
1874 struct variables *next = top_vars;
1875 if (cur->flg_read_only) {
1876 bb_error_msg("%s: readonly variable", name);
1879 if (cur->flg_export)
1880 unsetenv(cur->name);
1881 free((char*)cur->name);
1882 free((char*)cur->value);
1883 while (next->next != cur)
1885 next->next = cur->next;
1891 static int is_assignment(const char *s)
1893 if (!s || !isalpha(*s))
1896 while (isalnum(*s) || *s == '_')
1901 /* the src parameter allows us to peek forward to a possible &n syntax
1902 * for file descriptor duplication, e.g., "2>&1".
1903 * Return code is 0 normally, 1 if a syntax error is detected in src.
1904 * Resource errors (in xmalloc) cause the process to exit */
1905 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
1906 struct in_str *input)
1908 struct child_prog *child = ctx->child;
1909 struct redir_struct *redir = child->redirects;
1910 struct redir_struct *last_redir = NULL;
1912 /* Create a new redir_struct and drop it onto the end of the linked list */
1915 redir = redir->next;
1917 redir = xmalloc(sizeof(struct redir_struct));
1919 redir->word.gl_pathv = NULL;
1921 last_redir->next = redir;
1923 child->redirects = redir;
1926 redir->type = style;
1927 redir->fd = (fd == -1) ? redir_table[style].default_fd : fd;
1929 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
1931 /* Check for a '2>&1' type redirect */
1932 redir->dup = redirect_dup_num(input);
1933 if (redir->dup == -2) return 1; /* syntax error */
1934 if (redir->dup != -1) {
1935 /* Erik had a check here that the file descriptor in question
1936 * is legit; I postpone that to "run time"
1937 * A "-" representation of "close me" shows up as a -3 here */
1938 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
1940 /* We do _not_ try to open the file that src points to,
1941 * since we need to return and let src be expanded first.
1942 * Set ctx->pending_redirect, so we know what to do at the
1943 * end of the next parsed word.
1945 ctx->pending_redirect = redir;
1950 static struct pipe *new_pipe(void) {
1952 pi = xmalloc(sizeof(struct pipe));
1956 pi->followup = 0; /* invalid */
1957 pi->r_mode = RES_NONE;
1961 static void initialize_context(struct p_context *ctx)
1964 ctx->pending_redirect = NULL;
1966 ctx->list_head = new_pipe();
1967 ctx->pipe = ctx->list_head;
1971 done_command(ctx); /* creates the memory for working child */
1974 /* normal return is 0
1975 * if a reserved word is found, and processed, return 1
1976 * should handle if, then, elif, else, fi, for, while, until, do, done.
1977 * case, function, and select are obnoxious, save those for later.
1979 static int reserved_word(o_string *dest, struct p_context *ctx)
1981 struct reserved_combo {
1986 /* Mostly a list of accepted follow-up reserved words.
1987 * FLAG_END means we are done with the sequence, and are ready
1988 * to turn the compound list into a command.
1989 * FLAG_START means the word must start a new compound list.
1991 static struct reserved_combo reserved_list[] = {
1992 { "if", RES_IF, FLAG_THEN | FLAG_START },
1993 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
1994 { "elif", RES_ELIF, FLAG_THEN },
1995 { "else", RES_ELSE, FLAG_FI },
1996 { "fi", RES_FI, FLAG_END },
1997 { "for", RES_FOR, FLAG_IN | FLAG_START },
1998 { "while", RES_WHILE, FLAG_DO | FLAG_START },
1999 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
2000 { "in", RES_IN, FLAG_DO },
2001 { "do", RES_DO, FLAG_DONE },
2002 { "done", RES_DONE, FLAG_END }
2004 struct reserved_combo *r;
2005 #define NRES sizeof(reserved_list)/sizeof(struct reserved_combo)
2006 for (r = reserved_list; r < reserved_list+NRES; r++) {
2007 if (strcmp(dest->data, r->literal) == 0) {
2008 debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2009 if (r->flag & FLAG_START) {
2010 struct p_context *new = xmalloc(sizeof(struct p_context));
2011 debug_printf("push stack\n");
2012 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2019 *new = *ctx; /* physical copy */
2020 initialize_context(ctx);
2022 } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2029 ctx->old_flag = r->flag;
2030 if (ctx->old_flag & FLAG_END) {
2031 struct p_context *old;
2032 debug_printf("pop stack\n");
2033 done_pipe(ctx,PIPE_SEQ);
2035 old->child->group = ctx->list_head;
2036 old->child->subshell = 0;
2037 *ctx = *old; /* physical copy */
2047 /* normal return is 0.
2048 * Syntax or xglob errors return 1. */
2049 static int done_word(o_string *dest, struct p_context *ctx)
2051 struct child_prog *child=ctx->child;
2052 glob_t *glob_target;
2055 debug_printf("done_word: %s %p\n", dest->data, child);
2056 if (dest->length == 0 && !dest->nonnull) {
2057 debug_printf(" true null, ignored\n");
2060 if (ctx->pending_redirect) {
2061 glob_target = &ctx->pending_redirect->word;
2065 return 1; /* syntax error, groups and arglists don't mix */
2067 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2068 debug_printf("checking %s for reserved-ness\n",dest->data);
2069 if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2071 glob_target = &child->glob_result;
2072 if (child->argv) flags |= GLOB_APPEND;
2074 gr = xglob(dest, flags, glob_target);
2075 if (gr != 0) return 1;
2078 if (ctx->pending_redirect) {
2079 ctx->pending_redirect=NULL;
2080 if (glob_target->gl_pathc != 1) {
2081 bb_error_msg("ambiguous redirect");
2085 child->argv = glob_target->gl_pathv;
2087 if (ctx->w == RES_FOR) {
2088 done_word(dest,ctx);
2089 done_pipe(ctx,PIPE_SEQ);
2094 /* The only possible error here is out of memory, in which case
2096 static int done_command(struct p_context *ctx)
2098 /* The child is really already in the pipe structure, so
2099 * advance the pipe counter and make a new, null child.
2100 * Only real trickiness here is that the uncommitted
2101 * child structure, to which ctx->child points, is not
2102 * counted in pi->num_progs. */
2103 struct pipe *pi=ctx->pipe;
2104 struct child_prog *prog=ctx->child;
2106 if (prog && prog->group == NULL
2107 && prog->argv == NULL
2108 && prog->redirects == NULL) {
2109 debug_printf("done_command: skipping null command\n");
2113 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2115 debug_printf("done_command: initializing\n");
2117 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2119 prog = pi->progs + pi->num_progs;
2120 prog->redirects = NULL;
2122 prog->is_stopped = 0;
2124 prog->glob_result.gl_pathv = NULL;
2128 prog->type = ctx->type;
2130 /* but ctx->pipe and ctx->list_head remain unchanged */
2134 static int done_pipe(struct p_context *ctx, pipe_style type)
2137 done_command(ctx); /* implicit closure of previous command */
2138 debug_printf("done_pipe, type %d\n", type);
2139 ctx->pipe->followup = type;
2140 ctx->pipe->r_mode = ctx->w;
2142 ctx->pipe->next = new_p;
2145 done_command(ctx); /* set up new pipe to accept commands */
2149 /* peek ahead in the in_str to find out if we have a "&n" construct,
2150 * as in "2>&1", that represents duplicating a file descriptor.
2151 * returns either -2 (syntax error), -1 (no &), or the number found.
2153 static int redirect_dup_num(struct in_str *input)
2157 if (ch != '&') return -1;
2159 b_getch(input); /* get the & */
2163 return -3; /* "-" represents "close me" */
2165 while (isdigit(ch)) {
2173 bb_error_msg("ambiguous redirect");
2177 /* If a redirect is immediately preceded by a number, that number is
2178 * supposed to tell which file descriptor to redirect. This routine
2179 * looks for such preceding numbers. In an ideal world this routine
2180 * needs to handle all the following classes of redirects...
2181 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2182 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2183 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2184 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2185 * A -1 output from this program means no valid number was found, so the
2186 * caller should use the appropriate default for this redirection.
2188 static int redirect_opt_num(o_string *o)
2192 if (o->length==0) return -1;
2193 for (num=0; num<o->length; num++) {
2194 if (!isdigit(*(o->data+num))) {
2198 /* reuse num (and save an int) */
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");
2209 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
2215 bb_perror_msg_and_die("fork");
2216 } else if (pid==0) {
2218 if (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) { /* discard */ };
2262 debug_printf("done reading from pipe, pclose()ing\n");
2263 /* This is the step that wait()s for the child. Should be pretty
2264 * safe, since we just read an EOF from its stdout. We could try
2265 * to better, by using wait(), and keeping track of background jobs
2266 * at the same time. That would be a lot of work, and contrary
2267 * to the KISS philosophy of this program. */
2268 mark_closed(fileno(p));
2270 free_pipe_list(inner.list_head,0);
2271 debug_printf("pclosed, retcode=%d\n",retcode);
2272 /* XXX this process fails to trim a single trailing newline */
2276 static int parse_group(o_string *dest, struct p_context *ctx,
2277 struct in_str *input, int ch)
2280 struct p_context sub;
2281 struct child_prog *child = ctx->child;
2284 return 1; /* syntax error, groups and arglists don't mix */
2286 initialize_context(&sub);
2288 case '(': endch=')'; child->subshell=1; break;
2289 case '{': endch='}'; break;
2290 default: syntax(); /* really logic error */
2292 rcode=parse_stream(dest,&sub,input,endch);
2293 done_word(dest,&sub); /* finish off the final word in the subcontext */
2294 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2295 child->group = sub.list_head;
2297 /* child remains "open", available for possible redirects */
2300 /* basically useful version until someone wants to get fancier,
2301 * see the bash man page under "Parameter Expansion" */
2302 static const char *lookup_param(const char *src)
2304 const char *p = NULL;
2308 p = get_local_var(src);
2313 /* return code: 0 for OK, 1 for syntax error */
2314 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2318 int ch = input->peek(input); /* first character after the $ */
2319 debug_printf("handle_dollar: ch=%c\n",ch);
2321 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2323 while (ch=b_peek(input),isalnum(ch) || ch=='_') {
2327 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2328 } else if (isdigit(ch)) {
2329 i = ch-'0'; /* XXX is $0 special? */
2330 if (i<global_argc) {
2331 parse_string(dest, ctx, global_argv[i]); /* recursion */
2334 } else switch (ch) {
2336 b_adduint(dest,getpid());
2340 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2344 b_adduint(dest,last_return_code);
2348 b_adduint(dest,global_argc ? global_argc-1 : 0);
2352 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2355 /* XXX maybe someone will try to escape the '}' */
2356 while (ch=b_getch(input),ch!=EOF && ch!='}') {
2363 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2367 process_command_subs(dest, ctx, input, ')');
2371 for (i=1; i<global_argc; i++) {
2372 parse_string(dest, ctx, global_argv[i]);
2373 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2379 /* still unhandled, but should be eventually */
2380 bb_error_msg("unhandled syntax: $%c",ch);
2384 b_addqchr(dest,'$',dest->quote);
2386 /* Eat the character if the flag was set. If the compiler
2387 * is smart enough, we could substitute "b_getch(input);"
2388 * for all the "advance = 1;" above, and also end up with
2389 * a nice size-optimized program. Hah! That'll be the day.
2391 if (advance) b_getch(input);
2395 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2398 setup_string_in_str(&foo, src);
2399 return parse_stream(dest, ctx, &foo, '\0');
2402 /* return code is 0 for normal exit, 1 for syntax error */
2403 int parse_stream(o_string *dest, struct p_context *ctx,
2404 struct in_str *input, int end_trigger)
2408 redir_type redir_style;
2411 /* Only double-quote state is handled in the state variable dest->quote.
2412 * A single-quote triggers a bypass of the main loop until its mate is
2413 * found. When recursing, quote state is passed in via dest->quote. */
2415 debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2416 while ((ch=b_getch(input))!=EOF) {
2418 next = (ch == '\n') ? 0 : b_peek(input);
2419 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
2420 ch,ch,m,dest->quote);
2421 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2422 b_addqchr(dest, ch, dest->quote);
2424 if (m==2) { /* unquoted IFS */
2425 if (done_word(dest, ctx)) {
2428 /* If we aren't performing a substitution, treat a newline as a
2429 * command separator. */
2430 if (end_trigger != '\0' && ch=='\n')
2431 done_pipe(ctx,PIPE_SEQ);
2433 if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2434 debug_printf("leaving parse_stream (triggered)\n");
2437 if (m!=2) switch (ch) {
2439 if (dest->length == 0 && !dest->quote) {
2442 if (ch == EOF || ch == '\n')
2447 b_addqchr(dest, ch, dest->quote);
2455 b_addqchr(dest, '\\', dest->quote);
2456 b_addqchr(dest, b_getch(input), dest->quote);
2459 if (handle_dollar(dest, ctx, input)!=0) return 1;
2464 ch = b_getch(input);
2465 if (ch == EOF || ch == '\'')
2476 dest->quote = !dest->quote;
2479 process_command_subs(dest, ctx, input, '`');
2482 redir_fd = redirect_opt_num(dest);
2483 done_word(dest, ctx);
2484 redir_style=REDIRECT_OVERWRITE;
2486 redir_style=REDIRECT_APPEND;
2488 } else if (next == '(') {
2489 syntax(); /* until we support >(list) Process Substitution */
2492 setup_redirect(ctx, redir_fd, redir_style, input);
2495 redir_fd = redirect_opt_num(dest);
2496 done_word(dest, ctx);
2497 redir_style=REDIRECT_INPUT;
2499 redir_style=REDIRECT_HEREIS;
2501 } else if (next == '>') {
2502 redir_style=REDIRECT_IO;
2504 } else if (next == '(') {
2505 syntax(); /* until we support <(list) Process Substitution */
2508 setup_redirect(ctx, redir_fd, redir_style, input);
2511 done_word(dest, ctx);
2512 done_pipe(ctx,PIPE_SEQ);
2515 done_word(dest, ctx);
2518 done_pipe(ctx,PIPE_AND);
2520 done_pipe(ctx,PIPE_BG);
2524 done_word(dest, ctx);
2527 done_pipe(ctx,PIPE_OR);
2529 /* we could pick up a file descriptor choice here
2530 * with redirect_opt_num(), but bash doesn't do it.
2531 * "echo foo 2| cat" yields "foo 2". */
2537 if (parse_group(dest, ctx, input, ch)!=0) return 1;
2541 syntax(); /* Proper use of this character caught by end_trigger */
2545 syntax(); /* this is really an internal logic error */
2550 /* complain if quote? No, maybe we just finished a command substitution
2551 * that was quoted. Example:
2552 * $ echo "`cat foo` plus more"
2553 * and we just got the EOF generated by the subshell that ran "cat foo"
2554 * The only real complaint is if we got an EOF when end_trigger != '\0',
2555 * that is, we were really supposed to get end_trigger, and never got
2556 * one before the EOF. Can't use the standard "syntax error" return code,
2557 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
2558 debug_printf("leaving parse_stream (EOF)\n");
2559 if (end_trigger != '\0') return -1;
2563 static void mapset(const char *set, int code)
2565 const unsigned char *s;
2566 for (s = (const unsigned char *)set; *s; s++) map[(int)*s] = code;
2569 static void update_ifs_map(void)
2571 /* char *ifs and char map[256] are both globals. */
2572 ifs = getenv("IFS");
2573 if (ifs == NULL) ifs=" \t\n";
2574 /* Precompute a list of 'flow through' behavior so it can be treated
2575 * quickly up front. Computation is necessary because of IFS.
2576 * Special case handling of IFS == " \t\n" is not implemented.
2577 * The map[] array only really needs two bits each, and on most machines
2578 * that would be faster because of the reduced L1 cache footprint.
2580 memset(map,0,sizeof(map)); /* most characters flow through always */
2581 mapset("\\$'\"`", 3); /* never flow through */
2582 mapset("<>;&|(){}#", 1); /* flow through if quoted */
2583 mapset(ifs, 2); /* also flow through if quoted */
2586 /* most recursion does not come through here, the exception is
2587 * from builtin_source() */
2588 int parse_stream_outer(struct in_str *inp, int flag)
2591 struct p_context ctx;
2592 o_string temp=NULL_O_STRING;
2596 initialize_context(&ctx);
2598 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
2600 rcode = parse_stream(&temp, &ctx, inp, '\n');
2601 if (rcode != 1 && ctx.old_flag != 0) {
2604 if (rcode != 1 && ctx.old_flag == 0) {
2605 done_word(&temp, &ctx);
2606 done_pipe(&ctx,PIPE_SEQ);
2607 run_list(ctx.list_head);
2609 if (ctx.old_flag != 0) {
2616 free_pipe_list(ctx.list_head,0);
2619 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
2623 static int parse_string_outer(const char *s, int flag)
2625 struct in_str input;
2626 setup_string_in_str(&input, s);
2627 return parse_stream_outer(&input, flag);
2630 static int parse_file_outer(FILE *f)
2633 struct in_str input;
2634 setup_file_in_str(&input, f);
2635 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
2639 /* Make sure we have a controlling tty. If we get started under a job
2640 * aware app (like bash for example), make sure we are now in charge so
2641 * we don't fight over who gets the foreground */
2642 static void setup_job_control(void)
2644 static pid_t shell_pgrp;
2645 /* Loop until we are in the foreground. */
2646 while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
2647 kill (- shell_pgrp, SIGTTIN);
2649 /* Ignore interactive and job-control signals. */
2650 signal(SIGINT, SIG_IGN);
2651 signal(SIGQUIT, SIG_IGN);
2652 signal(SIGTERM, SIG_IGN);
2653 signal(SIGTSTP, SIG_IGN);
2654 signal(SIGTTIN, SIG_IGN);
2655 signal(SIGTTOU, SIG_IGN);
2656 signal(SIGCHLD, SIG_IGN);
2658 /* Put ourselves in our own process group. */
2660 shell_pgrp = getpid();
2661 setpgid(shell_pgrp, shell_pgrp);
2663 /* Grab control of the terminal. */
2664 tcsetpgrp(shell_terminal, shell_pgrp);
2667 int hush_main(int argc, char **argv)
2673 #if ENABLE_FEATURE_EDITING
2674 line_input_state = new_line_input_t(FOR_SHELL);
2677 /* XXX what should these be while sourcing /etc/profile? */
2681 /* (re?) initialize globals. Sometimes hush_main() ends up calling
2682 * hush_main(), therefore we cannot rely on the BSS to zero out this
2683 * stuff. Reset these to 0 every time. */
2685 /* map[] is taken care of with call to update_ifs_map() */
2688 close_me_head = NULL;
2693 /* Initialize some more globals to non-zero values */
2695 if (ENABLE_FEATURE_EDITING)
2696 cmdedit_set_initial_prompt();
2700 /* initialize our shell local variables with the values
2701 * currently living in the environment */
2704 set_local_var(*e, 2); /* without call putenv() */
2707 last_return_code=EXIT_SUCCESS;
2710 if (argv[0] && argv[0][0] == '-') {
2711 debug_printf("\nsourcing /etc/profile\n");
2712 if ((input = fopen("/etc/profile", "r")) != NULL) {
2713 mark_open(fileno(input));
2714 parse_file_outer(input);
2715 mark_closed(fileno(input));
2721 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
2725 global_argv = argv+optind;
2726 global_argc = argc-optind;
2727 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
2739 fprintf(stderr, "Usage: sh [FILE]...\n"
2740 " or: sh -c command [args]...\n\n");
2747 /* A shell is interactive if the `-i' flag was given, or if all of
2748 * the following conditions are met:
2750 * no arguments remaining or the -s flag given
2751 * standard input is a terminal
2752 * standard output is a terminal
2753 * Refer to Posix.2, the description of the `sh' utility. */
2754 if (argv[optind]==NULL && input==stdin &&
2755 isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
2759 debug_printf("\ninteractive=%d\n", interactive);
2761 /* Looks like they want an interactive shell */
2762 #if !ENABLE_FEATURE_SH_EXTRA_QUIET
2763 printf( "\n\n%s hush - the humble shell v0.01 (testing)\n",
2765 printf( "Enter 'help' for a list of built-in commands.\n\n");
2767 setup_job_control();
2770 if (argv[optind]==NULL) {
2771 opt=parse_file_outer(stdin);
2775 debug_printf("\nrunning script '%s'\n", argv[optind]);
2776 global_argv = argv+optind;
2777 global_argc = argc-optind;
2778 input = xfopen(argv[optind], "r");
2779 opt = parse_file_outer(input);
2781 #if ENABLE_FEATURE_CLEAN_UP
2783 if (cwd && cwd != bb_msg_unknown)
2786 struct variables *cur, *tmp;
2787 for (cur = top_vars; cur; cur = tmp) {
2789 if (!cur->flg_read_only) {
2799 return opt ? opt : last_return_code;
2802 static char *insert_var_value(char *inp)
2804 int res_str_len = 0;
2807 char *p, *res_str = NULL;
2810 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
2813 res_str = xrealloc(res_str, (res_str_len + len));
2814 strncpy((res_str + res_str_len), inp, len);
2818 p = strchr(inp, SPECIAL_VAR_SYMBOL);
2820 p1 = lookup_param(inp);
2822 len = res_str_len + strlen(p1);
2823 res_str = xrealloc(res_str, (1 + len));
2824 strcpy((res_str + res_str_len), p1);
2827 *p = SPECIAL_VAR_SYMBOL;
2832 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
2833 strcpy((res_str + res_str_len), inp);
2834 while ((p = strchr(res_str, '\n'))) {
2838 return (res_str == NULL) ? inp : res_str;
2841 static char **make_list_in(char **inp, char *name)
2844 int name_len = strlen(name);
2849 /* create list of variable values */
2850 list = xmalloc(sizeof(*list));
2851 for (i = 0; inp[i]; i++) {
2852 p3 = insert_var_value(inp[i]);
2859 if ((p2 = strchr(p1, ' '))) {
2865 /* we use n + 2 in realloc for list,because we add
2866 * new element and then we will add NULL element */
2867 list = xrealloc(list, sizeof(*list) * (n + 2));
2868 list[n] = xmalloc(2 + name_len + len);
2869 strcpy(list[n], name);
2870 strcat(list[n], "=");
2871 strncat(list[n], p1, len);
2872 list[n++][name_len + len + 1] = '\0';
2875 if (p3 != inp[i]) free(p3);
2881 /* Make new string for parser */
2882 static char * make_string(char ** inp)
2889 for (n = 0; inp[n]; n++) {
2890 p = insert_var_value(inp[n]);
2891 str = xrealloc(str, (len + strlen(p)));
2898 len = strlen(str) + 3;
2899 if (p != inp[n]) free(p);
2902 *(str + len) = '\n';
2903 *(str + len + 1) = '\0';