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 {
113 { O_RDONLY, 0, "<" },
114 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
115 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
116 { O_RDONLY, -1, "<<" },
127 /* might eventually control execution */
144 #define FLAG_END (1<<RES_NONE)
145 #define FLAG_IF (1<<RES_IF)
146 #define FLAG_THEN (1<<RES_THEN)
147 #define FLAG_ELIF (1<<RES_ELIF)
148 #define FLAG_ELSE (1<<RES_ELSE)
149 #define FLAG_FI (1<<RES_FI)
150 #define FLAG_FOR (1<<RES_FOR)
151 #define FLAG_WHILE (1<<RES_WHILE)
152 #define FLAG_UNTIL (1<<RES_UNTIL)
153 #define FLAG_DO (1<<RES_DO)
154 #define FLAG_DONE (1<<RES_DONE)
155 #define FLAG_IN (1<<RES_IN)
156 #define FLAG_START (1<<RES_XXXX)
158 /* This holds pointers to the various results of parsing */
160 struct child_prog *child;
161 struct pipe *list_head;
163 struct redir_struct *pending_redirect;
165 int old_flag; /* for figuring out valid reserved words */
166 struct p_context *stack;
167 int type; /* define type of parser : ";$" common or special symbol */
168 /* How about quoting status? */
171 struct redir_struct {
172 redir_type type; /* type of redirection */
173 int fd; /* file descriptor being redirected */
174 int dup; /* -1, or file descriptor being duplicated */
175 struct redir_struct *next; /* pointer to the next redirect in the list */
176 glob_t word; /* *word.gl_pathv is the filename */
180 pid_t pid; /* 0 if exited */
181 char **argv; /* program name and arguments */
182 struct pipe *group; /* if non-NULL, first in group or subshell */
183 int subshell; /* flag, non-zero if group must be forked */
184 struct redir_struct *redirects; /* I/O redirections */
185 glob_t glob_result; /* result of parameter globbing */
186 int is_stopped; /* is the program currently running? */
187 struct pipe *family; /* pointer back to the child's parent pipe */
188 int sp; /* number of SPECIAL_VAR_SYMBOL */
193 int jobid; /* job number */
194 int num_progs; /* total number of programs in job */
195 int running_progs; /* number of programs running */
196 char *text; /* name of job */
197 char *cmdbuf; /* buffer various argv's point into */
198 pid_t pgrp; /* process group ID for the job */
199 struct child_prog *progs; /* array of commands in pipe */
200 struct pipe *next; /* to track background commands */
201 int stopped_progs; /* number of programs alive, but stopped */
202 int job_context; /* bitmask defining current context */
203 pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
204 reserved_style r_mode; /* supports if, for, while, until */
209 struct close_me *next;
217 struct variables *next;
220 /* globals, connect us to the outside world
221 * the first three support $?, $#, and $1 */
222 static char **global_argv;
223 static int global_argc;
224 static int last_return_code;
225 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
227 /* "globals" within this file */
228 static const char *ifs;
229 static unsigned char map[256];
230 static int fake_mode;
231 static int interactive;
232 static struct close_me *close_me_head;
233 static const char *cwd;
234 static struct pipe *job_list;
235 static unsigned last_bg_pid;
236 static int last_jobid;
237 static unsigned shell_terminal;
238 static const char *PS1;
239 static const char *PS2;
240 static struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
241 static struct variables *top_vars = &shell_ver;
244 #define B_CHUNK (100)
254 #define NULL_O_STRING {NULL,0,0,0,0}
255 /* used for initialization:
256 o_string foo = NULL_O_STRING; */
258 /* I can almost use ordinary FILE *. Is open_memstream() universally
259 * available? Where is it documented? */
266 int (*get) (struct in_str *);
267 int (*peek) (struct in_str *);
269 #define b_getch(input) ((input)->get(input))
270 #define b_peek(input) ((input)->peek(input))
272 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
274 struct built_in_command {
275 const char *cmd; /* name */
276 const char *descr; /* description */
277 int (*function) (struct child_prog *); /* function ptr */
280 /* belongs in busybox.h */
281 static int max(int a, int b)
286 /* This should be in utility.c */
288 static void debug_printf(const char *format, ...)
291 va_start(args, format);
292 vfprintf(stderr, format, args);
295 /* broken, of course, but OK for testing */
296 static char *indenter(int i)
298 static char blanks[] = " ";
299 return &blanks[sizeof(blanks)-i-1];
302 #define debug_printf(...) do {;} while (0);
304 #define final_printf debug_printf
306 static void __syntax(const char *file, int line)
308 bb_error_msg("syntax error %s:%d", file, line);
310 // NB: was __FILE__, but that produces full path sometimess, so...
311 #define syntax() __syntax("hush.c", __LINE__)
313 /* Index of subroutines: */
314 /* function prototypes for builtins */
315 static int builtin_cd(struct child_prog *child);
316 static int builtin_env(struct child_prog *child);
317 static int builtin_eval(struct child_prog *child);
318 static int builtin_exec(struct child_prog *child);
319 static int builtin_exit(struct child_prog *child);
320 static int builtin_export(struct child_prog *child);
321 static int builtin_fg_bg(struct child_prog *child);
322 static int builtin_help(struct child_prog *child);
323 static int builtin_jobs(struct child_prog *child);
324 static int builtin_pwd(struct child_prog *child);
325 static int builtin_read(struct child_prog *child);
326 static int builtin_set(struct child_prog *child);
327 static int builtin_shift(struct child_prog *child);
328 static int builtin_source(struct child_prog *child);
329 static int builtin_umask(struct child_prog *child);
330 static int builtin_unset(struct child_prog *child);
331 static int builtin_not_written(struct child_prog *child);
332 /* o_string manipulation: */
333 static int b_check_space(o_string *o, int len);
334 static int b_addchr(o_string *o, int ch);
335 static void b_reset(o_string *o);
336 static int b_addqchr(o_string *o, int ch, int quote);
337 static int b_adduint(o_string *o, unsigned i);
338 /* in_str manipulations: */
339 static int static_get(struct in_str *i);
340 static int static_peek(struct in_str *i);
341 static int file_get(struct in_str *i);
342 static int file_peek(struct in_str *i);
343 static void setup_file_in_str(struct in_str *i, FILE *f);
344 static void setup_string_in_str(struct in_str *i, const char *s);
345 /* close_me manipulations: */
346 static void mark_open(int fd);
347 static void mark_closed(int fd);
348 static void close_all(void);
349 /* "run" the final data structures: */
350 static int free_pipe_list(struct pipe *head, int indent);
351 static int free_pipe(struct pipe *pi, int indent);
352 /* really run the final data structures: */
353 static int setup_redirects(struct child_prog *prog, int squirrel[]);
354 static int run_list_real(struct pipe *pi);
355 static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN;
356 static int run_pipe_real(struct pipe *pi);
357 /* extended glob support: */
358 static int globhack(const char *src, int flags, glob_t *pglob);
359 static int glob_needed(const char *s);
360 static int xglob(o_string *dest, int flags, glob_t *pglob);
361 /* variable assignment: */
362 static int is_assignment(const char *s);
363 /* data structure manipulation: */
364 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
365 static void initialize_context(struct p_context *ctx);
366 static int done_word(o_string *dest, struct p_context *ctx);
367 static int done_command(struct p_context *ctx);
368 static int done_pipe(struct p_context *ctx, pipe_style type);
369 /* primary string parsing: */
370 static int redirect_dup_num(struct in_str *input);
371 static int redirect_opt_num(o_string *o);
372 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
373 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
374 static const char *lookup_param(const char *src);
375 static char *make_string(char **inp);
376 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
377 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
378 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
380 static int parse_stream_outer(struct in_str *inp, int flag);
381 static int parse_string_outer(const char *s, int flag);
382 static int parse_file_outer(FILE *f);
383 /* job management: */
384 static int checkjobs(struct pipe* fg_pipe);
385 static void insert_bg_job(struct pipe *pi);
386 static void remove_bg_job(struct pipe *pi);
387 /* local variable support */
388 static char **make_list_in(char **inp, char *name);
389 static char *insert_var_value(char *inp);
390 static const char *get_local_var(const char *var);
391 static void unset_local_var(const char *name);
392 static int set_local_var(const char *s, int flg_export);
394 /* Table of built-in functions. They can be forked or not, depending on
395 * context: within pipes, they fork. As simple commands, they do not.
396 * When used in non-forking context, they can change global variables
397 * in the parent shell process. If forked, of course they cannot.
398 * For example, 'unset foo | whatever' will parse and run, but foo will
399 * still be set at the end. */
400 static const struct built_in_command bltins[] = {
401 { "bg", "Resume a job in the background", builtin_fg_bg },
402 { "break", "Exit for, while or until loop", builtin_not_written },
403 { "cd", "Change working directory", builtin_cd },
404 { "continue", "Continue for, while or until loop", builtin_not_written },
405 { "env", "Print all environment variables", builtin_env },
406 { "eval", "Construct and run shell command", builtin_eval },
407 { "exec", "Exec command, replacing this shell with the exec'd process",
409 { "exit", "Exit from shell()", builtin_exit },
410 { "export", "Set environment variable", builtin_export },
411 { "fg", "Bring job into the foreground", builtin_fg_bg },
412 { "jobs", "Lists the active jobs", builtin_jobs },
413 { "pwd", "Print current directory", builtin_pwd },
414 { "read", "Input environment variable", builtin_read },
415 { "return", "Return from a function", builtin_not_written },
416 { "set", "Set/unset shell local variables", builtin_set },
417 { "shift", "Shift positional parameters", builtin_shift },
418 { "trap", "Trap signals", builtin_not_written },
419 { "ulimit","Controls resource limits", builtin_not_written },
420 { "umask","Sets file creation mask", builtin_umask },
421 { "unset", "Unset environment variable", builtin_unset },
422 { ".", "Source-in and run commands in a file", builtin_source },
423 { "help", "List shell built-in commands", builtin_help },
427 static const char *set_cwd(void)
429 if (cwd == bb_msg_unknown)
430 cwd = NULL; /* xrealloc_getcwd_or_warn(arg) calls free(arg)! */
431 cwd = xrealloc_getcwd_or_warn((char *)cwd);
433 cwd = bb_msg_unknown;
437 /* built-in 'eval' handler */
438 static int builtin_eval(struct child_prog *child)
441 int rcode = EXIT_SUCCESS;
443 if (child->argv[1]) {
444 str = make_string(child->argv + 1);
445 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
446 FLAG_PARSE_SEMICOLON);
448 rcode = last_return_code;
453 /* built-in 'cd <path>' handler */
454 static int builtin_cd(struct child_prog *child)
457 if (child->argv[1] == NULL)
458 newdir = getenv("HOME");
460 newdir = child->argv[1];
462 printf("cd: %s: %s\n", newdir, strerror(errno));
469 /* built-in 'env' handler */
470 static int builtin_env(struct child_prog *dummy ATTRIBUTE_UNUSED)
481 /* built-in 'exec' handler */
482 static int builtin_exec(struct child_prog *child)
484 if (child->argv[1] == NULL)
485 return EXIT_SUCCESS; /* Really? */
491 /* built-in 'exit' handler */
492 static int builtin_exit(struct child_prog *child)
494 if (child->argv[1] == NULL)
495 exit(last_return_code);
496 exit(atoi(child->argv[1]));
499 /* built-in 'export VAR=value' handler */
500 static int builtin_export(struct child_prog *child)
503 char *name = child->argv[1];
506 return builtin_env(child);
512 const char *value = strchr(name, '=');
516 /* They are exporting something without an =VALUE */
518 value = get_local_var(name);
520 size_t ln = strlen(name);
522 tmp = realloc(name, ln+strlen(value)+2);
526 sprintf(tmp+ln, "=%s", value);
530 /* bash does not return an error when trying to export
531 * an undefined variable. Do likewise. */
537 bb_perror_msg("export");
539 res = set_local_var(name, 1);
546 /* built-in 'fg' and 'bg' handler */
547 static int builtin_fg_bg(struct child_prog *child)
554 /* If they gave us no args, assume they want the last backgrounded task */
555 if (!child->argv[1]) {
556 for (pi = job_list; pi; pi = pi->next) {
557 if (pi->jobid == last_jobid) {
561 bb_error_msg("%s: no current job", child->argv[0]);
564 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
565 bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
568 for (pi = job_list; pi; pi = pi->next) {
569 if (pi->jobid == jobnum) {
573 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 i = kill(- pi->pgrp, SIGCONT);
587 if (errno == ESRCH) {
590 bb_perror_msg("kill (SIGCONT)");
594 pi->stopped_progs = 0;
598 /* built-in 'help' handler */
599 static int builtin_help(struct child_prog *dummy ATTRIBUTE_UNUSED)
601 const struct built_in_command *x;
603 printf("\nBuilt-in commands:\n");
604 printf("-------------------\n");
605 for (x = bltins; x->cmd; x++) {
606 if (x->descr == NULL)
608 printf("%s\t%s\n", x->cmd, x->descr);
614 /* built-in 'jobs' handler */
615 static int builtin_jobs(struct child_prog *child ATTRIBUTE_UNUSED)
618 const char *status_string;
620 for (job = job_list; job; job = job->next) {
621 if (job->running_progs == job->stopped_progs)
622 status_string = "Stopped";
624 status_string = "Running";
626 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 */
698 /* Built-in '.' handler (read-in and execute commands from file) */
699 static int builtin_source(struct child_prog *child)
704 if (child->argv[1] == NULL)
707 /* XXX search through $PATH is missing */
708 input = fopen(child->argv[1], "r");
710 bb_error_msg("cannot open '%s'", child->argv[1]);
714 /* Now run the file */
715 /* XXX argv and argc are broken; need to save old global_argv
716 * (pointer only is OK!) on this stack frame,
717 * set global_argv=child->argv+1, recurse, and restore. */
718 mark_open(fileno(input));
719 status = parse_file_outer(input);
720 mark_closed(fileno(input));
725 static int builtin_umask(struct child_prog *child)
728 const char *arg = child->argv[1];
731 new_umask = strtoul(arg, &end, 8);
732 if (*end != '\0' || end == arg) {
736 new_umask = umask(0);
737 printf("%.3o\n", (unsigned) new_umask);
743 /* built-in 'unset VAR' handler */
744 static int builtin_unset(struct child_prog *child)
746 /* bash returned already true */
747 unset_local_var(child->argv[1]);
751 static int builtin_not_written(struct child_prog *child)
753 printf("builtin_%s not written\n", child->argv[0]);
757 static int b_check_space(o_string *o, int len)
759 /* It would be easy to drop a more restrictive policy
760 * in here, such as setting a maximum string length */
761 if (o->length + len > o->maxlen) {
762 char *old_data = o->data;
763 /* assert(data == NULL || o->maxlen != 0); */
764 o->maxlen += max(2*len, B_CHUNK);
765 o->data = realloc(o->data, 1 + o->maxlen);
766 if (o->data == NULL) {
770 return o->data == NULL;
773 static int b_addchr(o_string *o, int ch)
775 debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
776 if (b_check_space(o, 1))
778 o->data[o->length] = ch;
780 o->data[o->length] = '\0';
784 static void b_reset(o_string *o)
792 static void b_free(o_string *o)
800 /* My analysis of quoting semantics tells me that state information
801 * is associated with a destination, not a source.
803 static int b_addqchr(o_string *o, int ch, int quote)
805 if (quote && strchr("*?[\\", ch)) {
807 rc = b_addchr(o, '\\');
811 return b_addchr(o, ch);
814 /* belongs in utility.c */
815 static char *simple_itoa(unsigned i)
817 static char local[sizeof(int)*3 + 2];
818 char *p = &local[sizeof(int)*3 + 2 - 1];
827 static int b_adduint(o_string *o, unsigned i)
830 char *p = simple_itoa(i);
831 /* no escape checking necessary */
832 do r = b_addchr(o, *p++); while (r == 0 && *p);
836 static int static_get(struct in_str *i)
839 if (ch == '\0') return EOF;
843 static int static_peek(struct in_str *i)
848 static void cmdedit_set_initial_prompt(void)
850 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
859 static const char* setup_prompt_string(int promptmode)
861 const 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) {
868 ns = xmalloc(strlen(cwd)+4);
869 sprintf(ns, "%s %s", cwd, (geteuid() != 0) ? "$ " : "# ");
876 prompt_str = (promptmode == 1) ? PS1 : PS2;
878 debug_printf("result %s\n", prompt_str);
882 #if ENABLE_FEATURE_EDITING
883 static line_input_t *line_input_state;
886 static void get_user_input(struct in_str *i)
888 const char *prompt_str;
889 static char the_command[BUFSIZ];
891 prompt_str = setup_prompt_string(i->promptmode);
892 #if ENABLE_FEATURE_EDITING
894 ** enable command line editing only while a command line
895 ** is actually being read; otherwise, we'll end up bequeathing
896 ** atexit() handlers and other unwanted stuff to our
897 ** child processes (rob@sysgo.de)
899 read_line_input(prompt_str, the_command, BUFSIZ, line_input_state);
901 fputs(prompt_str, stdout);
903 the_command[0] = fgetc(i->file);
904 the_command[1] = '\0';
910 /* This is the magic location that prints prompts
911 * and gets data back from the user */
912 static int file_get(struct in_str *i)
917 /* If there is data waiting, eat it up */
921 /* need to double check i->file because we might be doing something
922 * more complicated by now, like sourcing or substituting. */
923 if (i->__promptme && interactive && i->file == stdin) {
924 while (!i->p || !(interactive && strlen(i->p))) {
936 debug_printf("b_getch: got a %d\n", ch);
943 /* All the callers guarantee this routine will never be
944 * used right after a newline, so prompting is not needed.
946 static int file_peek(struct in_str *i)
951 i->peek_buf[0] = fgetc(i->file);
952 i->peek_buf[1] = '\0';
954 debug_printf("b_peek: got a %d\n", *i->p);
958 static void setup_file_in_str(struct in_str *i, FILE *f)
968 static void setup_string_in_str(struct in_str *i, const char *s)
970 i->peek = static_peek;
977 static void mark_open(int fd)
979 struct close_me *new = xmalloc(sizeof(struct close_me));
981 new->next = close_me_head;
985 static void mark_closed(int fd)
987 struct close_me *tmp;
988 if (close_me_head == NULL || close_me_head->fd != fd)
989 bb_error_msg_and_die("corrupt close_me");
991 close_me_head = close_me_head->next;
995 static void close_all(void)
998 for (c = close_me_head; c; c = c->next) {
1001 close_me_head = NULL;
1004 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1005 * and stderr if they are redirected. */
1006 static int setup_redirects(struct child_prog *prog, int squirrel[])
1009 struct redir_struct *redir;
1011 for (redir = prog->redirects; redir; redir = redir->next) {
1012 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1013 /* something went wrong in the parse. Pretend it didn't happen */
1016 if (redir->dup == -1) {
1017 mode = redir_table[redir->type].mode;
1018 openfd = open_or_warn(redir->word.gl_pathv[0], mode);
1020 /* this could get lost if stderr has been redirected, but
1021 bash and ash both lose it as well (though zsh doesn't!) */
1025 openfd = redir->dup;
1028 if (openfd != redir->fd) {
1029 if (squirrel && redir->fd < 3) {
1030 squirrel[redir->fd] = dup(redir->fd);
1035 dup2(openfd, redir->fd);
1036 if (redir->dup == -1)
1044 static void restore_redirects(int squirrel[])
1047 for (i = 0; i < 3; i++) {
1050 /* No error checking. I sure wouldn't know what
1051 * to do with an error if I found one! */
1059 /* XXX no exit() here. If you don't exec, use _exit instead.
1060 * The at_exit handlers apparently confuse the calling process,
1061 * in particular stdin handling. Not sure why? */
1062 static void pseudo_exec(struct child_prog *child)
1066 const struct built_in_command *x;
1068 for (i = 0; is_assignment(child->argv[i]); i++) {
1069 debug_printf("pid %d environment modification: %s\n",
1070 getpid(), child->argv[i]);
1071 p = insert_var_value(child->argv[i]);
1073 if (p != child->argv[i])
1076 child->argv += i; /* XXX this hack isn't so horrible, since we are about
1077 to exit, and therefore don't need to keep data
1078 structures consistent for free() use. */
1079 /* If a variable is assigned in a forest, and nobody listens,
1080 * was it ever really set?
1082 if (child->argv[0] == NULL) {
1083 _exit(EXIT_SUCCESS);
1087 * Check if the command matches any of the builtins.
1088 * Depending on context, this might be redundant. But it's
1089 * easier to waste a few CPU cycles than it is to figure out
1090 * if this is one of those cases.
1092 for (x = bltins; x->cmd; x++) {
1093 if (strcmp(child->argv[0], x->cmd) == 0) {
1094 debug_printf("builtin exec %s\n", child->argv[0]);
1095 rcode = x->function(child);
1101 /* Check if the command matches any busybox internal commands
1103 * FIXME: This feature is not 100% safe, since
1104 * BusyBox is not fully reentrant, so we have no guarantee the things
1105 * from the .bss are still zeroed, or that things from .data are still
1106 * at their defaults. We could exec ourself from /proc/self/exe, but I
1107 * really dislike relying on /proc for things. We could exec ourself
1108 * from global_argv[0], but if we are in a chroot, we may not be able
1109 * to find ourself... */
1110 #if ENABLE_FEATURE_SH_STANDALONE
1111 debug_printf("running applet %s\n", child->argv[0]);
1112 run_applet_and_exit(child->argv[0], child->argv);
1113 // is it ok that run_applet_and_exit() does exit(), not _exit()?
1114 // NB: IIRC on NOMMU we are after _vfork_, not fork!
1116 debug_printf("exec of %s\n", child->argv[0]);
1117 execvp(child->argv[0], child->argv);
1118 bb_perror_msg("cannot exec: %s", child->argv[0]);
1123 debug_printf("runtime nesting to group\n");
1124 interactive = 0; /* crucial!!!! */
1125 rcode = run_list_real(child->group);
1126 /* OK to leak memory by not calling free_pipe_list,
1127 * since this process is about to exit */
1131 /* Can happen. See what bash does with ">foo" by itself. */
1132 debug_printf("trying to pseudo_exec null command\n");
1133 _exit(EXIT_SUCCESS);
1136 static void insert_bg_job(struct pipe *pi)
1138 struct pipe *thejob;
1140 /* Linear search for the ID of the job to use */
1142 for (thejob = job_list; thejob; thejob = thejob->next)
1143 if (thejob->jobid >= pi->jobid)
1144 pi->jobid = thejob->jobid + 1;
1146 /* add thejob to the list of running jobs */
1148 thejob = job_list = xmalloc(sizeof(*thejob));
1150 for (thejob = job_list; thejob->next; thejob = thejob->next)
1152 thejob->next = xmalloc(sizeof(*thejob));
1153 thejob = thejob->next;
1156 /* physically copy the struct job */
1157 memcpy(thejob, pi, sizeof(struct pipe));
1158 thejob->next = NULL;
1159 thejob->running_progs = thejob->num_progs;
1160 thejob->stopped_progs = 0;
1161 thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1163 //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0])
1165 char *bar = thejob->text;
1166 char **foo = pi->progs[0].argv;
1169 bar += sprintf(bar, "%s ", *foo++);
1172 /* we don't wait for background thejobs to return -- append it
1173 to the list of backgrounded thejobs and leave it alone */
1174 printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1175 last_bg_pid = thejob->progs[0].pid;
1176 last_jobid = thejob->jobid;
1179 /* remove a backgrounded job */
1180 static void remove_bg_job(struct pipe *pi)
1182 struct pipe *prev_pipe;
1184 if (pi == job_list) {
1185 job_list = pi->next;
1187 prev_pipe = job_list;
1188 while (prev_pipe->next != pi)
1189 prev_pipe = prev_pipe->next;
1190 prev_pipe->next = pi->next;
1193 last_jobid = job_list->jobid;
1197 pi->stopped_progs = 0;
1202 /* Checks to see if any processes have exited -- if they
1203 have, figure out why and see if a job has completed */
1204 static int checkjobs(struct pipe* fg_pipe)
1212 attributes = WUNTRACED;
1213 if (fg_pipe == NULL) {
1214 attributes |= WNOHANG;
1217 while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1220 for (i = 0; i < fg_pipe->num_progs; i++) {
1221 if (fg_pipe->progs[i].pid == childpid) {
1222 if (i == fg_pipe->num_progs-1)
1223 rcode = WEXITSTATUS(status);
1224 fg_pipe->num_progs--;
1230 for (pi = job_list; pi; pi = pi->next) {
1232 while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1235 if (prognum < pi->num_progs)
1240 debug_printf("checkjobs: pid %d was not in our list!\n",
1245 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1247 pi->running_progs--;
1248 pi->progs[prognum].pid = 0;
1250 if (!pi->running_progs) {
1251 printf(JOB_STATUS_FORMAT, pi->jobid,
1257 pi->stopped_progs++;
1258 pi->progs[prognum].is_stopped = 1;
1262 if (childpid == -1 && errno != ECHILD)
1263 bb_perror_msg("waitpid");
1265 /* move the shell to the foreground */
1266 //if (interactive && tcsetpgrp(shell_terminal, getpgid(0)))
1267 // bb_perror_msg("tcsetpgrp-2");
1271 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1272 * to finish. See checkjobs().
1274 * return code is normally -1, when the caller has to wait for children
1275 * to finish to determine the exit status of the pipe. If the pipe
1276 * is a simple builtin command, however, the action is done by the
1277 * time run_pipe_real returns, and the exit code is provided as the
1280 * The input of the pipe is always stdin, the output is always
1281 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1282 * because it tries to avoid running the command substitution in
1283 * subshell, when that is in fact necessary. The subshell process
1284 * now has its stdout directed to the input of the appropriate pipe,
1285 * so this routine is noticeably simpler.
1287 static int run_pipe_real(struct pipe *pi)
1290 int nextin, nextout;
1291 int pipefds[2]; /* pipefds[0] is for reading */
1292 struct child_prog *child;
1293 const struct built_in_command *x;
1295 /* it is not always needed, but we aim to smaller code */
1296 int squirrel[] = { -1, -1, -1 };
1302 /* Check if this is a simple builtin (not part of a pipe).
1303 * Builtins within pipes have to fork anyway, and are handled in
1304 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1306 child = &(pi->progs[0]);
1307 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1308 debug_printf("non-subshell grouping\n");
1309 setup_redirects(child, squirrel);
1310 /* XXX could we merge code with following builtin case,
1311 * by creating a pseudo builtin that calls run_list_real? */
1312 rcode = run_list_real(child->group);
1313 restore_redirects(squirrel);
1317 if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1318 for (i = 0; is_assignment(child->argv[i]); i++)
1320 if (i != 0 && child->argv[i] == NULL) {
1321 /* assignments, but no command: set the local environment */
1322 for (i = 0; child->argv[i] != NULL; i++) {
1323 /* Ok, this case is tricky. We have to decide if this is a
1324 * local variable, or an already exported variable. If it is
1325 * already exported, we have to export the new value. If it is
1326 * not exported, we need only set this as a local variable.
1327 * This junk is all to decide whether or not to export this
1331 name = xstrdup(child->argv[i]);
1332 debug_printf("Local environment set: %s\n", name);
1333 value = strchr(name, '=');
1336 if (get_local_var(name)) {
1340 p = insert_var_value(child->argv[i]);
1341 set_local_var(p, export_me);
1342 if (p != child->argv[i])
1345 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1347 for (i = 0; is_assignment(child->argv[i]); i++) {
1348 p = insert_var_value(child->argv[i]);
1350 if (p != child->argv[i]) {
1358 str = make_string(child->argv + i);
1359 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1361 return last_return_code;
1363 for (x = bltins; x->cmd; x++) {
1364 if (strcmp(child->argv[i], x->cmd) == 0) {
1365 if (x->function == builtin_exec && child->argv[i+1] == NULL) {
1366 debug_printf("magic exec\n");
1367 setup_redirects(child, NULL);
1368 return EXIT_SUCCESS;
1370 debug_printf("builtin inline %s\n", child->argv[0]);
1371 /* XXX setup_redirects acts on file descriptors, not FILEs.
1372 * This is perfect for work that comes after exec().
1373 * Is it really safe for inline use? Experimentally,
1374 * things seem to work with glibc. */
1375 setup_redirects(child, squirrel);
1376 child->argv += i; /* XXX horrible hack */
1377 rcode = x->function(child);
1378 child->argv -= i; /* XXX restore hack so free() can work right */
1379 restore_redirects(squirrel);
1383 #if ENABLE_FEATURE_SH_STANDALONE
1385 const struct bb_applet *a = find_applet_by_name(child->argv[i]);
1386 if (a && a->nofork) {
1387 setup_redirects(child, squirrel);
1388 rcode = run_nofork_applet(a, child->argv + i);
1389 restore_redirects(squirrel);
1396 for (i = 0; i < pi->num_progs; i++) {
1397 child = &(pi->progs[i]);
1399 /* pipes are inserted between pairs of commands */
1400 if ((i + 1) < pi->num_progs) {
1401 if (pipe(pipefds) < 0)
1402 bb_perror_msg_and_die("pipe");
1403 nextout = pipefds[1];
1409 /* XXX test for failed fork()? */
1411 child->pid = fork();
1413 child->pid = vfork();
1416 /* Set the handling for job control signals back to the default. */
1417 signal(SIGINT, SIG_DFL);
1418 signal(SIGQUIT, SIG_DFL);
1419 signal(SIGTERM, SIG_DFL);
1420 signal(SIGTSTP, SIG_DFL);
1421 signal(SIGTTIN, SIG_DFL);
1422 signal(SIGTTOU, SIG_DFL);
1423 signal(SIGCHLD, SIG_DFL);
1435 if (pipefds[0] != -1) {
1436 close(pipefds[0]); /* opposite end of our output pipe */
1439 /* Like bash, explicit redirects override pipes,
1440 * and the pipe fd is available for dup'ing. */
1441 setup_redirects(child, NULL);
1443 if (interactive && pi->followup != PIPE_BG) {
1444 /* If we (the child) win the race, put ourselves in the process
1445 * group whose leader is the first process in this pipe. */
1447 pi->pgrp = getpid();
1449 if (setpgid(0, pi->pgrp) == 0) {
1450 tcsetpgrp(2, pi->pgrp);
1457 /* put our child in the process group whose leader is the
1458 first process in this pipe */
1460 pi->pgrp = child->pid;
1462 /* Don't check for errors. The child may be dead already,
1463 * in which case setpgid returns error code EACCES. */
1464 setpgid(child->pid, pi->pgrp);
1471 /* If there isn't another process, nextin is garbage
1472 but it doesn't matter */
1473 nextin = pipefds[0];
1478 static int run_list_real(struct pipe *pi)
1480 char *save_name = NULL;
1482 char **save_list = NULL;
1486 int rcode = 0, flag_skip = 1;
1487 int flag_restore = 0;
1488 int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
1489 reserved_style rmode, skip_more_in_this_rmode = RES_XXXX;
1490 /* check syntax for "for" */
1491 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1492 if ((rpipe->r_mode == RES_IN || rpipe->r_mode == RES_FOR)
1493 && (rpipe->next == NULL)
1498 if ((rpipe->r_mode == RES_IN && rpipe->next->r_mode == RES_IN && rpipe->next->progs->argv != NULL)
1499 || (rpipe->r_mode == RES_FOR && rpipe->next->r_mode != RES_IN)
1505 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1506 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL
1507 || pi->r_mode == RES_FOR
1516 debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n",
1517 rmode, if_code, next_if_code, skip_more_in_this_rmode);
1518 if (rmode == skip_more_in_this_rmode && flag_skip) {
1519 if (pi->followup == PIPE_SEQ)
1524 skip_more_in_this_rmode = RES_XXXX;
1525 if (rmode == RES_THEN || rmode == RES_ELSE)
1526 if_code = next_if_code;
1527 if (rmode == RES_THEN && if_code)
1529 if (rmode == RES_ELSE && !if_code)
1531 if (rmode == RES_ELIF && !if_code)
1533 if (rmode == RES_FOR && pi->num_progs) {
1535 /* if no variable values after "in" we skip "for" */
1536 if (!pi->next->progs->argv)
1538 /* create list of variable values */
1539 list = make_list_in(pi->next->progs->argv,
1540 pi->progs->argv[0]);
1542 save_name = pi->progs->argv[0];
1543 pi->progs->argv[0] = NULL;
1547 free(pi->progs->argv[0]);
1551 pi->progs->argv[0] = save_name;
1552 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1555 /* insert new value from list for variable */
1556 if (pi->progs->argv[0])
1557 free(pi->progs->argv[0]);
1558 pi->progs->argv[0] = *list++;
1559 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1562 if (rmode == RES_IN)
1564 if (rmode == RES_DO) {
1568 if ((rmode == RES_DONE)) {
1575 if (pi->num_progs == 0)
1577 save_num_progs = pi->num_progs; /* save number of programs */
1578 rcode = run_pipe_real(pi);
1579 debug_printf("run_pipe_real returned %d\n", rcode);
1581 /* We only ran a builtin: rcode was set by the return value
1582 * of run_pipe_real(), and we don't need to wait for anything. */
1583 } else if (pi->followup == PIPE_BG) {
1584 /* XXX check bash's behavior with nontrivial pipes */
1585 /* XXX compute jobid */
1586 /* XXX what does bash do with attempts to background builtins? */
1588 rcode = EXIT_SUCCESS;
1591 /* move the new process group into the foreground */
1592 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1593 bb_perror_msg("tcsetpgrp-3");
1594 rcode = checkjobs(pi);
1595 /* move the shell to the foreground */
1596 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1597 bb_perror_msg("tcsetpgrp-4");
1599 rcode = checkjobs(pi);
1601 debug_printf("checkjobs returned %d\n", rcode);
1603 last_return_code = rcode;
1604 pi->num_progs = save_num_progs; /* restore number of programs */
1605 if ( rmode == RES_IF || rmode == RES_ELIF )
1606 next_if_code = rcode; /* can be overwritten a number of times */
1607 if (rmode == RES_WHILE)
1608 flag_rep = !last_return_code;
1609 if (rmode == RES_UNTIL)
1610 flag_rep = last_return_code;
1611 if ((rcode == EXIT_SUCCESS && pi->followup == PIPE_OR)
1612 || (rcode != EXIT_SUCCESS && pi->followup == PIPE_AND)
1614 skip_more_in_this_rmode = rmode;
1621 /* return code is the exit status of the pipe */
1622 static int free_pipe(struct pipe *pi, int indent)
1625 struct child_prog *child;
1626 struct redir_struct *r, *rnext;
1627 int a, i, ret_code = 0;
1629 if (pi->stopped_progs > 0)
1631 final_printf("%s run pipe: (pid %d)\n", indenter(indent), getpid());
1632 for (i = 0; i < pi->num_progs; i++) {
1633 child = &pi->progs[i];
1634 final_printf("%s command %d:\n", indenter(indent), i);
1636 for (a = 0, p = child->argv; *p; a++, p++) {
1637 final_printf("%s argv[%d] = %s\n", indenter(indent), a, *p);
1639 globfree(&child->glob_result);
1641 } else if (child->group) {
1642 final_printf("%s begin group (subshell:%d)\n", indenter(indent), child->subshell);
1643 ret_code = free_pipe_list(child->group, indent+3);
1644 final_printf("%s end group\n", indenter(indent));
1646 final_printf("%s (nil)\n", indenter(indent));
1648 for (r = child->redirects; r; r = rnext) {
1649 final_printf("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip);
1651 /* guard against the case >$FOO, where foo is unset or blank */
1652 if (r->word.gl_pathv) {
1653 final_printf(" %s\n", *r->word.gl_pathv);
1657 final_printf("&%d\n", r->dup);
1662 child->redirects = NULL;
1664 free(pi->progs); /* children are an array, they get freed all at once */
1669 static int free_pipe_list(struct pipe *head, int indent)
1671 int rcode = 0; /* if list has no members */
1672 struct pipe *pi, *next;
1673 for (pi = head; pi; pi = next) {
1674 final_printf("%s pipe reserved mode %d\n", indenter(indent), pi->r_mode);
1675 rcode = free_pipe(pi, indent);
1676 final_printf("%s pipe followup code %d\n", indenter(indent), pi->followup);
1684 /* Select which version we will use */
1685 static int run_list(struct pipe *pi)
1688 if (fake_mode == 0) {
1689 rcode = run_list_real(pi);
1691 /* free_pipe_list has the side effect of clearing memory
1692 * In the long run that function can be merged with run_list_real,
1693 * but doing that now would hobble the debugging effort. */
1694 free_pipe_list(pi,0);
1698 /* The API for glob is arguably broken. This routine pushes a non-matching
1699 * string into the output structure, removing non-backslashed backslashes.
1700 * If someone can prove me wrong, by performing this function within the
1701 * original glob(3) api, feel free to rewrite this routine into oblivion.
1702 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
1703 * XXX broken if the last character is '\\', check that before calling.
1705 static int globhack(const char *src, int flags, glob_t *pglob)
1710 for (cnt = 1, s = src; s && *s; s++) {
1711 if (*s == '\\') s++;
1715 if (!dest) return GLOB_NOSPACE;
1716 if (!(flags & GLOB_APPEND)) {
1717 pglob->gl_pathv = NULL;
1718 pglob->gl_pathc = 0;
1722 pathc = ++pglob->gl_pathc;
1723 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
1724 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
1725 pglob->gl_pathv[pathc-1] = dest;
1726 pglob->gl_pathv[pathc] = NULL;
1727 for (s = src; s && *s; s++, dest++) {
1728 if (*s == '\\') s++;
1735 /* XXX broken if the last character is '\\', check that before calling */
1736 static int glob_needed(const char *s)
1739 if (*s == '\\') s++;
1740 if (strchr("*[?", *s)) return 1;
1745 static int xglob(o_string *dest, int flags, glob_t *pglob)
1749 /* short-circuit for null word */
1750 /* we can code this better when the debug_printf's are gone */
1751 if (dest->length == 0) {
1752 if (dest->nonnull) {
1753 /* bash man page calls this an "explicit" null */
1754 gr = globhack(dest->data, flags, pglob);
1755 debug_printf("globhack returned %d\n", gr);
1759 } else if (glob_needed(dest->data)) {
1760 gr = glob(dest->data, flags, NULL, pglob);
1761 debug_printf("glob returned %d\n", gr);
1762 if (gr == GLOB_NOMATCH) {
1763 /* quote removal, or more accurately, backslash removal */
1764 gr = globhack(dest->data, flags, pglob);
1765 debug_printf("globhack returned %d\n", gr);
1768 gr = globhack(dest->data, flags, pglob);
1769 debug_printf("globhack returned %d\n", gr);
1771 if (gr == GLOB_NOSPACE)
1772 bb_error_msg_and_die("out of memory during glob");
1773 if (gr != 0) { /* GLOB_ABORTED ? */
1774 bb_error_msg("glob(3) error %d", gr);
1776 /* globprint(glob_target); */
1780 /* This is used to get/check local shell variables */
1781 static const char *get_local_var(const char *s)
1783 struct variables *cur;
1787 for (cur = top_vars; cur; cur = cur->next)
1788 if (strcmp(cur->name, s) == 0)
1793 /* This is used to set local shell variables
1794 flg_export == 0 if only local (not exporting) variable
1795 flg_export == 1 if "new" exporting environ
1796 flg_export > 1 if current startup environ (not call putenv()) */
1797 static int set_local_var(const char *s, int flg_export)
1801 struct variables *cur;
1805 /* Assume when we enter this function that we are already in
1806 * NAME=VALUE format. So the first order of business is to
1807 * split 's' on the '=' into 'name' and 'value' */
1808 value = strchr(name, '=');
1809 /*if (value == 0 && ++value == 0) ??? -vda */
1810 if (value == NULL || value[1] == '\0') {
1816 for (cur = top_vars; cur; cur = cur->next) {
1817 if (strcmp(cur->name, name) == 0)
1822 if (strcmp(cur->value, value) == 0) {
1823 if (flg_export > 0 && cur->flg_export == 0)
1824 cur->flg_export = flg_export;
1827 } else if (cur->flg_read_only) {
1828 bb_error_msg("%s: readonly variable", name);
1831 if (flg_export > 0 || cur->flg_export > 1)
1832 cur->flg_export = 1;
1833 free((char*)cur->value);
1835 cur->value = strdup(value);
1838 cur = malloc(sizeof(struct variables));
1842 cur->name = strdup(name);
1847 struct variables *bottom = top_vars;
1848 cur->value = strdup(value);
1850 cur->flg_export = flg_export;
1851 cur->flg_read_only = 0;
1852 while (bottom->next)
1853 bottom = bottom->next;
1859 if (result == 0 && cur->flg_export == 1) {
1861 result = putenv(name);
1864 if (result > 0) /* equivalent to previous set */
1870 static void unset_local_var(const char *name)
1872 struct variables *cur;
1875 for (cur = top_vars; cur; cur = cur->next) {
1876 if (strcmp(cur->name, name) == 0)
1880 struct variables *next = top_vars;
1881 if (cur->flg_read_only) {
1882 bb_error_msg("%s: readonly variable", name);
1885 if (cur->flg_export)
1886 unsetenv(cur->name);
1887 free((char*)cur->name);
1888 free((char*)cur->value);
1889 while (next->next != cur)
1891 next->next = cur->next;
1897 static int is_assignment(const char *s)
1899 if (!s || !isalpha(*s))
1902 while (isalnum(*s) || *s == '_')
1907 /* the src parameter allows us to peek forward to a possible &n syntax
1908 * for file descriptor duplication, e.g., "2>&1".
1909 * Return code is 0 normally, 1 if a syntax error is detected in src.
1910 * Resource errors (in xmalloc) cause the process to exit */
1911 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
1912 struct in_str *input)
1914 struct child_prog *child = ctx->child;
1915 struct redir_struct *redir = child->redirects;
1916 struct redir_struct *last_redir = NULL;
1918 /* Create a new redir_struct and drop it onto the end of the linked list */
1921 redir = redir->next;
1923 redir = xmalloc(sizeof(struct redir_struct));
1925 redir->word.gl_pathv = NULL;
1927 last_redir->next = redir;
1929 child->redirects = redir;
1932 redir->type = style;
1933 redir->fd = (fd == -1) ? redir_table[style].default_fd : fd;
1935 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
1937 /* Check for a '2>&1' type redirect */
1938 redir->dup = redirect_dup_num(input);
1939 if (redir->dup == -2) return 1; /* syntax error */
1940 if (redir->dup != -1) {
1941 /* Erik had a check here that the file descriptor in question
1942 * is legit; I postpone that to "run time"
1943 * A "-" representation of "close me" shows up as a -3 here */
1944 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
1946 /* We do _not_ try to open the file that src points to,
1947 * since we need to return and let src be expanded first.
1948 * Set ctx->pending_redirect, so we know what to do at the
1949 * end of the next parsed word.
1951 ctx->pending_redirect = redir;
1956 static struct pipe *new_pipe(void)
1959 pi = xmalloc(sizeof(struct pipe));
1963 pi->followup = 0; /* invalid */
1964 pi->r_mode = RES_NONE;
1968 static void initialize_context(struct p_context *ctx)
1971 ctx->pending_redirect = NULL;
1973 ctx->list_head = new_pipe();
1974 ctx->pipe = ctx->list_head;
1978 done_command(ctx); /* creates the memory for working child */
1981 /* normal return is 0
1982 * if a reserved word is found, and processed, return 1
1983 * should handle if, then, elif, else, fi, for, while, until, do, done.
1984 * case, function, and select are obnoxious, save those for later.
1986 static int reserved_word(o_string *dest, struct p_context *ctx)
1988 struct reserved_combo {
1989 const char *literal;
1993 /* Mostly a list of accepted follow-up reserved words.
1994 * FLAG_END means we are done with the sequence, and are ready
1995 * to turn the compound list into a command.
1996 * FLAG_START means the word must start a new compound list.
1998 static const struct reserved_combo reserved_list[] = {
1999 { "if", RES_IF, FLAG_THEN | FLAG_START },
2000 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2001 { "elif", RES_ELIF, FLAG_THEN },
2002 { "else", RES_ELSE, FLAG_FI },
2003 { "fi", RES_FI, FLAG_END },
2004 { "for", RES_FOR, FLAG_IN | FLAG_START },
2005 { "while", RES_WHILE, FLAG_DO | FLAG_START },
2006 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
2007 { "in", RES_IN, FLAG_DO },
2008 { "do", RES_DO, FLAG_DONE },
2009 { "done", RES_DONE, FLAG_END }
2011 const struct reserved_combo *r;
2012 #define NRES sizeof(reserved_list)/sizeof(reserved_list[0])
2014 for (r = reserved_list; r < reserved_list+NRES; r++) {
2015 if (strcmp(dest->data, r->literal) == 0) {
2016 debug_printf("found reserved word %s, code %d\n", r->literal, r->code);
2017 if (r->flag & FLAG_START) {
2018 struct p_context *new = xmalloc(sizeof(struct p_context));
2019 debug_printf("push stack\n");
2020 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2027 *new = *ctx; /* physical copy */
2028 initialize_context(ctx);
2030 } else if (ctx->w == RES_NONE || !(ctx->old_flag & (1 << r->code))) {
2037 ctx->old_flag = r->flag;
2038 if (ctx->old_flag & FLAG_END) {
2039 struct p_context *old;
2040 debug_printf("pop stack\n");
2041 done_pipe(ctx, PIPE_SEQ);
2043 old->child->group = ctx->list_head;
2044 old->child->subshell = 0;
2045 *ctx = *old; /* physical copy */
2055 /* normal return is 0.
2056 * Syntax or xglob errors return 1. */
2057 static int done_word(o_string *dest, struct p_context *ctx)
2059 struct child_prog *child = ctx->child;
2060 glob_t *glob_target;
2063 debug_printf("done_word: %s %p\n", dest->data, child);
2064 if (dest->length == 0 && !dest->nonnull) {
2065 debug_printf(" true null, ignored\n");
2068 if (ctx->pending_redirect) {
2069 glob_target = &ctx->pending_redirect->word;
2073 return 1; /* syntax error, groups and arglists don't mix */
2075 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2076 debug_printf("checking %s for reserved-ness\n", dest->data);
2077 if (reserved_word(dest, ctx))
2078 return (ctx->w == RES_SNTX);
2080 glob_target = &child->glob_result;
2081 if (child->argv) flags |= GLOB_APPEND;
2083 gr = xglob(dest, flags, glob_target);
2084 if (gr != 0) return 1;
2087 if (ctx->pending_redirect) {
2088 ctx->pending_redirect = NULL;
2089 if (glob_target->gl_pathc != 1) {
2090 bb_error_msg("ambiguous redirect");
2094 child->argv = glob_target->gl_pathv;
2096 if (ctx->w == RES_FOR) {
2097 done_word(dest, ctx);
2098 done_pipe(ctx, PIPE_SEQ);
2103 /* The only possible error here is out of memory, in which case
2105 static int done_command(struct p_context *ctx)
2107 /* The child is really already in the pipe structure, so
2108 * advance the pipe counter and make a new, null child.
2109 * Only real trickiness here is that the uncommitted
2110 * child structure, to which ctx->child points, is not
2111 * counted in pi->num_progs. */
2112 struct pipe *pi = ctx->pipe;
2113 struct child_prog *prog = ctx->child;
2115 if (prog && prog->group == NULL
2116 && prog->argv == NULL
2117 && prog->redirects == NULL) {
2118 debug_printf("done_command: skipping null command\n");
2122 debug_printf("done_command: num_progs incremented to %d\n", pi->num_progs);
2124 debug_printf("done_command: initializing\n");
2126 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2128 prog = pi->progs + pi->num_progs;
2129 prog->redirects = NULL;
2131 prog->is_stopped = 0;
2133 prog->glob_result.gl_pathv = NULL;
2137 prog->type = ctx->type;
2139 /* but ctx->pipe and ctx->list_head remain unchanged */
2143 static int done_pipe(struct p_context *ctx, pipe_style type)
2146 done_command(ctx); /* implicit closure of previous command */
2147 debug_printf("done_pipe, type %d\n", type);
2148 ctx->pipe->followup = type;
2149 ctx->pipe->r_mode = ctx->w;
2151 ctx->pipe->next = new_p;
2154 done_command(ctx); /* set up new pipe to accept commands */
2158 /* peek ahead in the in_str to find out if we have a "&n" construct,
2159 * as in "2>&1", that represents duplicating a file descriptor.
2160 * returns either -2 (syntax error), -1 (no &), or the number found.
2162 static int redirect_dup_num(struct in_str *input)
2164 int ch, d = 0, ok = 0;
2166 if (ch != '&') return -1;
2168 b_getch(input); /* get the & */
2172 return -3; /* "-" represents "close me" */
2174 while (isdigit(ch)) {
2182 bb_error_msg("ambiguous redirect");
2186 /* If a redirect is immediately preceded by a number, that number is
2187 * supposed to tell which file descriptor to redirect. This routine
2188 * looks for such preceding numbers. In an ideal world this routine
2189 * needs to handle all the following classes of redirects...
2190 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2191 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2192 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2193 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2194 * A -1 output from this program means no valid number was found, so the
2195 * caller should use the appropriate default for this redirection.
2197 static int redirect_opt_num(o_string *o)
2203 for (num = 0; num < o->length; num++) {
2204 if (!isdigit(*(o->data + num))) {
2208 /* reuse num (and save an int) */
2209 num = atoi(o->data);
2214 static FILE *generate_stream_from_list(struct pipe *head)
2217 int pid, channel[2];
2218 if (pipe(channel) < 0) bb_perror_msg_and_die("pipe");
2225 bb_perror_msg_and_die("fork");
2226 } else if (pid == 0) {
2228 if (channel[1] != 1) {
2232 _exit(run_list_real(head)); /* leaks memory */
2234 debug_printf("forked child %d\n", pid);
2236 pf = fdopen(channel[0],"r");
2237 debug_printf("pipe on FILE *%p\n", pf);
2241 /* this version hacked for testing purposes */
2242 /* return code is exit status of the process that is run. */
2243 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2246 o_string result = NULL_O_STRING;
2247 struct p_context inner;
2249 struct in_str pipe_str;
2250 initialize_context(&inner);
2252 /* recursion to generate command */
2253 retcode = parse_stream(&result, &inner, input, subst_end);
2254 if (retcode != 0) return retcode; /* syntax error or EOF */
2255 done_word(&result, &inner);
2256 done_pipe(&inner, PIPE_SEQ);
2259 p = generate_stream_from_list(inner.list_head);
2260 if (p == NULL) return 1;
2261 mark_open(fileno(p));
2262 setup_file_in_str(&pipe_str, p);
2264 /* now send results of command back into original context */
2265 retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2266 /* XXX In case of a syntax error, should we try to kill the child?
2267 * That would be tough to do right, so just read until EOF. */
2269 while (b_getch(&pipe_str) != EOF)
2273 debug_printf("done reading from pipe, pclose()ing\n");
2274 /* This is the step that wait()s for the child. Should be pretty
2275 * safe, since we just read an EOF from its stdout. We could try
2276 * to better, by using wait(), and keeping track of background jobs
2277 * at the same time. That would be a lot of work, and contrary
2278 * to the KISS philosophy of this program. */
2279 mark_closed(fileno(p));
2280 retcode = pclose(p);
2281 free_pipe_list(inner.list_head, 0);
2282 debug_printf("pclosed, retcode=%d\n", retcode);
2283 /* XXX this process fails to trim a single trailing newline */
2287 static int parse_group(o_string *dest, struct p_context *ctx,
2288 struct in_str *input, int ch)
2290 int rcode, endch = 0;
2291 struct p_context sub;
2292 struct child_prog *child = ctx->child;
2295 return 1; /* syntax error, groups and arglists don't mix */
2297 initialize_context(&sub);
2301 child->subshell = 1;
2307 syntax(); /* really logic error */
2309 rcode = parse_stream(dest, &sub, input, endch);
2310 done_word(dest, &sub); /* finish off the final word in the subcontext */
2311 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2312 child->group = sub.list_head;
2314 /* child remains "open", available for possible redirects */
2317 /* basically useful version until someone wants to get fancier,
2318 * see the bash man page under "Parameter Expansion" */
2319 static const char *lookup_param(const char *src)
2321 const char *p = NULL;
2325 p = get_local_var(src);
2330 /* return code: 0 for OK, 1 for syntax error */
2331 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2335 int ch = input->peek(input); /* first character after the $ */
2336 debug_printf("handle_dollar: ch=%c\n", ch);
2338 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2340 while (ch = b_peek(input), isalnum(ch) || ch == '_') {
2344 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2345 } else if (isdigit(ch)) {
2346 i = ch-'0'; /* XXX is $0 special? */
2347 if (i < global_argc) {
2348 parse_string(dest, ctx, global_argv[i]); /* recursion */
2351 } else switch (ch) {
2353 b_adduint(dest, getpid());
2357 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2361 b_adduint(dest, last_return_code);
2365 b_adduint(dest, global_argc ? global_argc-1 : 0);
2369 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2372 /* XXX maybe someone will try to escape the '}' */
2374 ch = b_getch(input);
2375 if (ch == EOF || ch == '}')
2383 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2387 process_command_subs(dest, ctx, input, ')');
2391 for (i = 1; i < global_argc; i++) {
2392 parse_string(dest, ctx, global_argv[i]);
2393 if (i+1 < global_argc)
2394 parse_string(dest, ctx, sep);
2400 /* still unhandled, but should be eventually */
2401 bb_error_msg("unhandled syntax: $%c", ch);
2405 b_addqchr(dest,'$', dest->quote);
2407 /* Eat the character if the flag was set. If the compiler
2408 * is smart enough, we could substitute "b_getch(input);"
2409 * for all the "advance = 1;" above, and also end up with
2410 * a nice size-optimized program. Hah! That'll be the day.
2412 if (advance) b_getch(input);
2416 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2419 setup_string_in_str(&foo, src);
2420 return parse_stream(dest, ctx, &foo, '\0');
2423 /* return code is 0 for normal exit, 1 for syntax error */
2424 int parse_stream(o_string *dest, struct p_context *ctx,
2425 struct in_str *input, int end_trigger)
2429 redir_type redir_style;
2432 /* Only double-quote state is handled in the state variable dest->quote.
2433 * A single-quote triggers a bypass of the main loop until its mate is
2434 * found. When recursing, quote state is passed in via dest->quote. */
2436 debug_printf("parse_stream, end_trigger=%d\n", end_trigger);
2437 while ((ch = b_getch(input)) != EOF) {
2439 next = (ch == '\n') ? 0 : b_peek(input);
2440 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
2441 ch, ch, m, dest->quote);
2442 if (m == 0 || ((m == 1 || m == 2) && dest->quote)) {
2443 b_addqchr(dest, ch, dest->quote);
2446 if (m == 2) { /* unquoted IFS */
2447 if (done_word(dest, ctx)) {
2450 /* If we aren't performing a substitution, treat a newline as a
2451 * command separator. */
2452 if (end_trigger != '\0' && ch == '\n')
2453 done_pipe(ctx, PIPE_SEQ);
2455 if (ch == end_trigger && !dest->quote && ctx->w == RES_NONE) {
2456 debug_printf("leaving parse_stream (triggered)\n");
2463 if (dest->length == 0 && !dest->quote) {
2466 if (ch == EOF || ch == '\n')
2471 b_addqchr(dest, ch, dest->quote);
2479 b_addqchr(dest, '\\', dest->quote);
2480 b_addqchr(dest, b_getch(input), dest->quote);
2483 if (handle_dollar(dest, ctx, input) != 0) return 1;
2488 ch = b_getch(input);
2489 if (ch == EOF || ch == '\'')
2500 dest->quote = !dest->quote;
2503 process_command_subs(dest, ctx, input, '`');
2506 redir_fd = redirect_opt_num(dest);
2507 done_word(dest, ctx);
2508 redir_style = REDIRECT_OVERWRITE;
2510 redir_style = REDIRECT_APPEND;
2512 } else if (next == '(') {
2513 syntax(); /* until we support >(list) Process Substitution */
2516 setup_redirect(ctx, redir_fd, redir_style, input);
2519 redir_fd = redirect_opt_num(dest);
2520 done_word(dest, ctx);
2521 redir_style = REDIRECT_INPUT;
2523 redir_style = REDIRECT_HEREIS;
2525 } else if (next == '>') {
2526 redir_style = REDIRECT_IO;
2528 } else if (next == '(') {
2529 syntax(); /* until we support <(list) Process Substitution */
2532 setup_redirect(ctx, redir_fd, redir_style, input);
2535 done_word(dest, ctx);
2536 done_pipe(ctx, PIPE_SEQ);
2539 done_word(dest, ctx);
2542 done_pipe(ctx, PIPE_AND);
2544 done_pipe(ctx, PIPE_BG);
2548 done_word(dest, ctx);
2551 done_pipe(ctx, PIPE_OR);
2553 /* we could pick up a file descriptor choice here
2554 * with redirect_opt_num(), but bash doesn't do it.
2555 * "echo foo 2| cat" yields "foo 2". */
2561 if (parse_group(dest, ctx, input, ch) != 0)
2566 syntax(); /* Proper use of this character caught by end_trigger */
2569 syntax(); /* this is really an internal logic error */
2573 /* complain if quote? No, maybe we just finished a command substitution
2574 * that was quoted. Example:
2575 * $ echo "`cat foo` plus more"
2576 * and we just got the EOF generated by the subshell that ran "cat foo"
2577 * The only real complaint is if we got an EOF when end_trigger != '\0',
2578 * that is, we were really supposed to get end_trigger, and never got
2579 * one before the EOF. Can't use the standard "syntax error" return code,
2580 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
2581 debug_printf("leaving parse_stream (EOF)\n");
2582 if (end_trigger != '\0')
2587 static void mapset(const char *set, int code)
2590 map[(unsigned char)*set++] = code;
2593 static void update_ifs_map(void)
2595 /* char *ifs and char map[256] are both globals. */
2596 ifs = getenv("IFS");
2597 if (ifs == NULL) ifs = " \t\n";
2598 /* Precompute a list of 'flow through' behavior so it can be treated
2599 * quickly up front. Computation is necessary because of IFS.
2600 * Special case handling of IFS == " \t\n" is not implemented.
2601 * The map[] array only really needs two bits each, and on most machines
2602 * that would be faster because of the reduced L1 cache footprint.
2604 memset(map, 0, sizeof(map)); /* most characters flow through always */
2605 mapset("\\$'\"`", 3); /* never flow through */
2606 mapset("<>;&|(){}#", 1); /* flow through if quoted */
2607 mapset(ifs, 2); /* also flow through if quoted */
2610 /* most recursion does not come through here, the exception is
2611 * from builtin_source() */
2612 int parse_stream_outer(struct in_str *inp, int flag)
2614 struct p_context ctx;
2615 o_string temp = NULL_O_STRING;
2619 initialize_context(&ctx);
2621 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
2622 inp->promptmode = 1;
2623 rcode = parse_stream(&temp, &ctx, inp, '\n');
2624 if (rcode != 1 && ctx.old_flag != 0) {
2627 if (rcode != 1 && ctx.old_flag == 0) {
2628 done_word(&temp, &ctx);
2629 done_pipe(&ctx, PIPE_SEQ);
2630 run_list(ctx.list_head);
2632 if (ctx.old_flag != 0) {
2639 free_pipe_list(ctx.list_head,0);
2642 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
2646 static int parse_string_outer(const char *s, int flag)
2648 struct in_str input;
2649 setup_string_in_str(&input, s);
2650 return parse_stream_outer(&input, flag);
2653 static int parse_file_outer(FILE *f)
2656 struct in_str input;
2657 setup_file_in_str(&input, f);
2658 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
2662 /* Make sure we have a controlling tty. If we get started under a job
2663 * aware app (like bash for example), make sure we are now in charge so
2664 * we don't fight over who gets the foreground */
2665 static void setup_job_control(void)
2667 /*static --why?? */ pid_t shell_pgrp;
2669 /* Loop until we are in the foreground. */
2670 while (tcgetpgrp(shell_terminal) != (shell_pgrp = getpgrp()))
2671 kill(- shell_pgrp, SIGTTIN);
2673 /* Ignore interactive and job-control signals. */
2674 signal(SIGINT, SIG_IGN);
2675 signal(SIGQUIT, SIG_IGN);
2676 signal(SIGTERM, SIG_IGN);
2677 signal(SIGTSTP, SIG_IGN);
2678 signal(SIGTTIN, SIG_IGN);
2679 signal(SIGTTOU, SIG_IGN);
2680 signal(SIGCHLD, SIG_IGN);
2682 /* Put ourselves in our own process group. */
2684 shell_pgrp = getpid();
2685 setpgid(shell_pgrp, shell_pgrp);
2687 /* Grab control of the terminal. */
2688 tcsetpgrp(shell_terminal, shell_pgrp);
2691 int hush_main(int argc, char **argv);
2692 int hush_main(int argc, char **argv)
2698 #if ENABLE_FEATURE_EDITING
2699 line_input_state = new_line_input_t(FOR_SHELL);
2702 /* XXX what should these be while sourcing /etc/profile? */
2706 /* (re?) initialize globals. Sometimes hush_main() ends up calling
2707 * hush_main(), therefore we cannot rely on the BSS to zero out this
2708 * stuff. Reset these to 0 every time. */
2710 /* map[] is taken care of with call to update_ifs_map() */
2713 close_me_head = NULL;
2718 /* Initialize some more globals to non-zero values */
2720 if (ENABLE_FEATURE_EDITING)
2721 cmdedit_set_initial_prompt();
2725 /* initialize our shell local variables with the values
2726 * currently living in the environment */
2730 set_local_var(*e++, 2); /* without call putenv() */
2732 last_return_code = EXIT_SUCCESS;
2734 if (argv[0] && argv[0][0] == '-') {
2735 debug_printf("\nsourcing /etc/profile\n");
2736 input = fopen("/etc/profile", "r");
2737 if (input != NULL) {
2738 mark_open(fileno(input));
2739 parse_file_outer(input);
2740 mark_closed(fileno(input));
2746 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
2749 global_argv = argv+optind;
2750 global_argc = argc-optind;
2751 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
2761 fprintf(stderr, "Usage: sh [FILE]...\n"
2762 " or: sh -c command [args]...\n\n");
2769 /* A shell is interactive if the '-i' flag was given, or if all of
2770 * the following conditions are met:
2772 * no arguments remaining or the -s flag given
2773 * standard input is a terminal
2774 * standard output is a terminal
2775 * Refer to Posix.2, the description of the 'sh' utility. */
2776 if (argv[optind] == NULL && input == stdin
2777 && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
2782 debug_printf("\ninteractive=%d\n", interactive);
2784 /* Looks like they want an interactive shell */
2785 #if !ENABLE_FEATURE_SH_EXTRA_QUIET
2786 printf( "\n\n%s hush - the humble shell v0.01 (testing)\n",
2788 printf( "Enter 'help' for a list of built-in commands.\n\n");
2790 setup_job_control();
2793 if (argv[optind] == NULL) {
2794 opt = parse_file_outer(stdin);
2798 debug_printf("\nrunning script '%s'\n", argv[optind]);
2799 global_argv = argv + optind;
2800 global_argc = argc - optind;
2801 input = xfopen(argv[optind], "r");
2802 opt = parse_file_outer(input);
2804 #if ENABLE_FEATURE_CLEAN_UP
2806 if (cwd != bb_msg_unknown)
2809 struct variables *cur, *tmp;
2810 for (cur = top_vars; cur; cur = tmp) {
2812 if (!cur->flg_read_only) {
2813 free((char*)cur->name);
2814 free((char*)cur->value);
2822 return opt ? opt : last_return_code;
2825 static char *insert_var_value(char *inp)
2827 int res_str_len = 0;
2830 char *p, *res_str = NULL;
2833 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
2836 res_str = xrealloc(res_str, (res_str_len + len));
2837 strncpy((res_str + res_str_len), inp, len);
2841 p = strchr(inp, SPECIAL_VAR_SYMBOL);
2843 p1 = lookup_param(inp);
2845 len = res_str_len + strlen(p1);
2846 res_str = xrealloc(res_str, (1 + len));
2847 strcpy((res_str + res_str_len), p1);
2850 *p = SPECIAL_VAR_SYMBOL;
2855 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
2856 strcpy((res_str + res_str_len), inp);
2857 while ((p = strchr(res_str, '\n'))) {
2861 return (res_str == NULL) ? inp : res_str;
2864 static char **make_list_in(char **inp, char *name)
2867 int name_len = strlen(name);
2872 /* create list of variable values */
2873 list = xmalloc(sizeof(*list));
2874 for (i = 0; inp[i]; i++) {
2875 p3 = insert_var_value(inp[i]);
2882 p2 = strchr(p1, ' ');
2889 /* we use n + 2 in realloc for list, because we add
2890 * new element and then we will add NULL element */
2891 list = xrealloc(list, sizeof(*list) * (n + 2));
2892 list[n] = xmalloc(2 + name_len + len);
2893 strcpy(list[n], name);
2894 strcat(list[n], "=");
2895 strncat(list[n], p1, len);
2896 list[n++][name_len + len + 1] = '\0';
2899 if (p3 != inp[i]) free(p3);
2905 /* Make new string for parser */
2906 static char* make_string(char ** inp)
2913 for (n = 0; inp[n]; n++) {
2914 p = insert_var_value(inp[n]);
2915 str = xrealloc(str, (len + strlen(p)));
2922 len = strlen(str) + 3;
2923 if (p != inp[n]) free(p);