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)
550 struct pipe *pi = NULL;
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) {
562 bb_error_msg("%s: no current job", child->argv[0]);
566 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
567 bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
570 for (pi = job_list; pi; pi = pi->next) {
571 if (pi->jobid == jobnum) {
576 bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
581 if (*child->argv[0] == 'f') {
582 /* Put the job into the foreground. */
583 tcsetpgrp(shell_terminal, pi->pgrp);
586 /* Restart the processes in the job */
587 for (i = 0; i < pi->num_progs; i++)
588 pi->progs[i].is_stopped = 0;
590 i = kill(- pi->pgrp, SIGCONT);
595 bb_perror_msg("kill (SIGCONT)");
599 pi->stopped_progs = 0;
603 /* built-in 'help' handler */
604 static int builtin_help(struct child_prog *dummy ATTRIBUTE_UNUSED)
606 const struct built_in_command *x;
608 printf("\nBuilt-in commands:\n");
609 printf("-------------------\n");
610 for (x = bltins; x->cmd; x++) {
611 if (x->descr == NULL)
613 printf("%s\t%s\n", x->cmd, x->descr);
619 /* built-in 'jobs' handler */
620 static int builtin_jobs(struct child_prog *child ATTRIBUTE_UNUSED)
623 const char *status_string;
625 for (job = job_list; job; job = job->next) {
626 if (job->running_progs == job->stopped_progs)
627 status_string = "Stopped";
629 status_string = "Running";
631 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
636 /* built-in 'pwd' handler */
637 static int builtin_pwd(struct child_prog *dummy ATTRIBUTE_UNUSED)
643 /* built-in 'read VAR' handler */
644 static int builtin_read(struct child_prog *child)
648 if (child->argv[1]) {
652 string[0] = '\0'; /* In case stdin has only EOF */
654 fgets(string, sizeof(string), stdin);
656 var = malloc(strlen(child->argv[1]) + strlen(string) + 2);
658 sprintf(var, "%s=%s", child->argv[1], string);
659 res = set_local_var(var, 0);
663 bb_perror_msg("read");
664 free(var); /* So not move up to avoid breaking errno */
667 do res = getchar(); while (res != '\n' && res != EOF);
671 /* built-in 'set VAR=value' handler */
672 static int builtin_set(struct child_prog *child)
674 char *temp = child->argv[1];
678 for (e = top_vars; e; e = e->next)
679 printf("%s=%s\n", e->name, e->value);
681 set_local_var(temp, 0);
687 /* Built-in 'shift' handler */
688 static int builtin_shift(struct child_prog *child)
691 if (child->argv[1]) {
692 n = atoi(child->argv[1]);
694 if (n >= 0 && n < global_argc) {
695 /* XXX This probably breaks $0 */
703 /* Built-in '.' handler (read-in and execute commands from file) */
704 static int builtin_source(struct child_prog *child)
709 if (child->argv[1] == NULL)
712 /* XXX search through $PATH is missing */
713 input = fopen(child->argv[1], "r");
715 bb_error_msg("cannot open '%s'", child->argv[1]);
719 /* Now run the file */
720 /* XXX argv and argc are broken; need to save old global_argv
721 * (pointer only is OK!) on this stack frame,
722 * set global_argv=child->argv+1, recurse, and restore. */
723 mark_open(fileno(input));
724 status = parse_file_outer(input);
725 mark_closed(fileno(input));
730 static int builtin_umask(struct child_prog *child)
733 const char *arg = child->argv[1];
736 new_umask = strtoul(arg, &end, 8);
737 if (*end != '\0' || end == arg) {
741 new_umask = umask(0);
742 printf("%.3o\n", (unsigned) new_umask);
748 /* built-in 'unset VAR' handler */
749 static int builtin_unset(struct child_prog *child)
751 /* bash returned already true */
752 unset_local_var(child->argv[1]);
756 static int builtin_not_written(struct child_prog *child)
758 printf("builtin_%s not written\n", child->argv[0]);
762 static int b_check_space(o_string *o, int len)
764 /* It would be easy to drop a more restrictive policy
765 * in here, such as setting a maximum string length */
766 if (o->length + len > o->maxlen) {
767 char *old_data = o->data;
768 /* assert(data == NULL || o->maxlen != 0); */
769 o->maxlen += max(2*len, B_CHUNK);
770 o->data = realloc(o->data, 1 + o->maxlen);
771 if (o->data == NULL) {
775 return o->data == NULL;
778 static int b_addchr(o_string *o, int ch)
780 debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
781 if (b_check_space(o, 1))
783 o->data[o->length] = ch;
785 o->data[o->length] = '\0';
789 static void b_reset(o_string *o)
797 static void b_free(o_string *o)
805 /* My analysis of quoting semantics tells me that state information
806 * is associated with a destination, not a source.
808 static int b_addqchr(o_string *o, int ch, int quote)
810 if (quote && strchr("*?[\\", ch)) {
812 rc = b_addchr(o, '\\');
816 return b_addchr(o, ch);
819 /* belongs in utility.c */
820 static char *simple_itoa(unsigned i)
822 static char local[sizeof(int)*3 + 2];
823 char *p = &local[sizeof(int)*3 + 2 - 1];
832 static int b_adduint(o_string *o, unsigned i)
835 char *p = simple_itoa(i);
836 /* no escape checking necessary */
837 do r = b_addchr(o, *p++); while (r == 0 && *p);
841 static int static_get(struct in_str *i)
844 if (ch == '\0') return EOF;
848 static int static_peek(struct in_str *i)
853 static void cmdedit_set_initial_prompt(void)
855 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
864 static const char* setup_prompt_string(int promptmode)
866 const char *prompt_str;
867 debug_printf("setup_prompt_string %d ", promptmode);
868 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
869 /* Set up the prompt */
870 if (promptmode == 1) {
873 ns = xmalloc(strlen(cwd)+4);
874 sprintf(ns, "%s %s", cwd, (geteuid() != 0) ? "$ " : "# ");
881 prompt_str = (promptmode == 1) ? PS1 : PS2;
883 debug_printf("result %s\n", prompt_str);
887 #if ENABLE_FEATURE_EDITING
888 static line_input_t *line_input_state;
891 static void get_user_input(struct in_str *i)
893 const char *prompt_str;
894 static char the_command[BUFSIZ];
896 prompt_str = setup_prompt_string(i->promptmode);
897 #if ENABLE_FEATURE_EDITING
899 ** enable command line editing only while a command line
900 ** is actually being read; otherwise, we'll end up bequeathing
901 ** atexit() handlers and other unwanted stuff to our
902 ** child processes (rob@sysgo.de)
904 read_line_input(prompt_str, the_command, BUFSIZ, line_input_state);
906 fputs(prompt_str, stdout);
908 the_command[0] = fgetc(i->file);
909 the_command[1] = '\0';
915 /* This is the magic location that prints prompts
916 * and gets data back from the user */
917 static int file_get(struct in_str *i)
922 /* If there is data waiting, eat it up */
926 /* need to double check i->file because we might be doing something
927 * more complicated by now, like sourcing or substituting. */
928 if (i->__promptme && interactive && i->file == stdin) {
929 while (!i->p || !(interactive && strlen(i->p))) {
941 debug_printf("b_getch: got a %d\n", ch);
948 /* All the callers guarantee this routine will never be
949 * used right after a newline, so prompting is not needed.
951 static int file_peek(struct in_str *i)
956 i->peek_buf[0] = fgetc(i->file);
957 i->peek_buf[1] = '\0';
959 debug_printf("b_peek: got a %d\n", *i->p);
963 static void setup_file_in_str(struct in_str *i, FILE *f)
973 static void setup_string_in_str(struct in_str *i, const char *s)
975 i->peek = static_peek;
982 static void mark_open(int fd)
984 struct close_me *new = xmalloc(sizeof(struct close_me));
986 new->next = close_me_head;
990 static void mark_closed(int fd)
992 struct close_me *tmp;
993 if (close_me_head == NULL || close_me_head->fd != fd)
994 bb_error_msg_and_die("corrupt close_me");
996 close_me_head = close_me_head->next;
1000 static void close_all(void)
1003 for (c = close_me_head; c; c = c->next) {
1006 close_me_head = NULL;
1009 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1010 * and stderr if they are redirected. */
1011 static int setup_redirects(struct child_prog *prog, int squirrel[])
1014 struct redir_struct *redir;
1016 for (redir = prog->redirects; redir; redir = redir->next) {
1017 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1018 /* something went wrong in the parse. Pretend it didn't happen */
1021 if (redir->dup == -1) {
1022 mode = redir_table[redir->type].mode;
1023 openfd = open_or_warn(redir->word.gl_pathv[0], mode);
1025 /* this could get lost if stderr has been redirected, but
1026 bash and ash both lose it as well (though zsh doesn't!) */
1030 openfd = redir->dup;
1033 if (openfd != redir->fd) {
1034 if (squirrel && redir->fd < 3) {
1035 squirrel[redir->fd] = dup(redir->fd);
1040 dup2(openfd, redir->fd);
1041 if (redir->dup == -1)
1049 static void restore_redirects(int squirrel[])
1052 for (i = 0; i < 3; i++) {
1055 /* No error checking. I sure wouldn't know what
1056 * to do with an error if I found one! */
1064 /* XXX no exit() here. If you don't exec, use _exit instead.
1065 * The at_exit handlers apparently confuse the calling process,
1066 * in particular stdin handling. Not sure why? */
1067 static void pseudo_exec(struct child_prog *child)
1071 const struct built_in_command *x;
1073 for (i = 0; is_assignment(child->argv[i]); i++) {
1074 debug_printf("pid %d environment modification: %s\n",
1075 getpid(), child->argv[i]);
1076 p = insert_var_value(child->argv[i]);
1078 if (p != child->argv[i])
1081 child->argv += i; /* XXX this hack isn't so horrible, since we are about
1082 to exit, and therefore don't need to keep data
1083 structures consistent for free() use. */
1084 /* If a variable is assigned in a forest, and nobody listens,
1085 * was it ever really set?
1087 if (child->argv[0] == NULL) {
1088 _exit(EXIT_SUCCESS);
1092 * Check if the command matches any of the builtins.
1093 * Depending on context, this might be redundant. But it's
1094 * easier to waste a few CPU cycles than it is to figure out
1095 * if this is one of those cases.
1097 for (x = bltins; x->cmd; x++) {
1098 if (strcmp(child->argv[0], x->cmd) == 0) {
1099 debug_printf("builtin exec %s\n", child->argv[0]);
1100 rcode = x->function(child);
1106 /* Check if the command matches any busybox internal commands
1108 * FIXME: This feature is not 100% safe, since
1109 * BusyBox is not fully reentrant, so we have no guarantee the things
1110 * from the .bss are still zeroed, or that things from .data are still
1111 * at their defaults. We could exec ourself from /proc/self/exe, but I
1112 * really dislike relying on /proc for things. We could exec ourself
1113 * from global_argv[0], but if we are in a chroot, we may not be able
1114 * to find ourself... */
1115 #if ENABLE_FEATURE_SH_STANDALONE
1116 debug_printf("running applet %s\n", child->argv[0]);
1117 run_applet_and_exit(child->argv[0], child->argv);
1118 // is it ok that run_applet_and_exit() does exit(), not _exit()?
1119 // NB: IIRC on NOMMU we are after _vfork_, not fork!
1121 debug_printf("exec of %s\n", child->argv[0]);
1122 execvp(child->argv[0], child->argv);
1123 bb_perror_msg("cannot exec: %s", child->argv[0]);
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 */
1136 /* Can happen. See what bash does with ">foo" by itself. */
1137 debug_printf("trying to pseudo_exec null command\n");
1138 _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;
1300 /* it is not always needed, but we aim to smaller code */
1301 int squirrel[] = { -1, -1, -1 };
1307 /* Check if this is a simple builtin (not part of a pipe).
1308 * Builtins within pipes have to fork anyway, and are handled in
1309 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1311 child = &(pi->progs[0]);
1312 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1313 debug_printf("non-subshell grouping\n");
1314 setup_redirects(child, squirrel);
1315 /* XXX could we merge code with following builtin case,
1316 * by creating a pseudo builtin that calls run_list_real? */
1317 rcode = run_list_real(child->group);
1318 restore_redirects(squirrel);
1322 if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1323 for (i = 0; is_assignment(child->argv[i]); i++)
1325 if (i != 0 && child->argv[i] == NULL) {
1326 /* assignments, but no command: set the local environment */
1327 for (i = 0; child->argv[i] != NULL; i++) {
1328 /* Ok, this case is tricky. We have to decide if this is a
1329 * local variable, or an already exported variable. If it is
1330 * already exported, we have to export the new value. If it is
1331 * not exported, we need only set this as a local variable.
1332 * This junk is all to decide whether or not to export this
1336 name = xstrdup(child->argv[i]);
1337 debug_printf("Local environment set: %s\n", name);
1338 value = strchr(name, '=');
1341 if (get_local_var(name)) {
1345 p = insert_var_value(child->argv[i]);
1346 set_local_var(p, export_me);
1347 if (p != child->argv[i])
1350 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1352 for (i = 0; is_assignment(child->argv[i]); i++) {
1353 p = insert_var_value(child->argv[i]);
1355 if (p != child->argv[i]) {
1363 str = make_string(child->argv + i);
1364 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1366 return last_return_code;
1368 for (x = bltins; x->cmd; x++) {
1369 if (strcmp(child->argv[i], x->cmd) == 0) {
1370 if (x->function == builtin_exec && child->argv[i+1] == NULL) {
1371 debug_printf("magic exec\n");
1372 setup_redirects(child, NULL);
1373 return EXIT_SUCCESS;
1375 debug_printf("builtin inline %s\n", child->argv[0]);
1376 /* XXX setup_redirects acts on file descriptors, not FILEs.
1377 * This is perfect for work that comes after exec().
1378 * Is it really safe for inline use? Experimentally,
1379 * things seem to work with glibc. */
1380 setup_redirects(child, squirrel);
1381 child->argv += i; /* XXX horrible hack */
1382 rcode = x->function(child);
1383 child->argv -= i; /* XXX restore hack so free() can work right */
1384 restore_redirects(squirrel);
1388 #if ENABLE_FEATURE_SH_STANDALONE
1390 const struct bb_applet *a = find_applet_by_name(child->argv[i]);
1391 if (a && a->nofork) {
1392 setup_redirects(child, squirrel);
1393 rcode = run_nofork_applet(a, child->argv + i);
1394 restore_redirects(squirrel);
1401 for (i = 0; i < pi->num_progs; i++) {
1402 child = &(pi->progs[i]);
1404 /* pipes are inserted between pairs of commands */
1405 if ((i + 1) < pi->num_progs) {
1406 if (pipe(pipefds) < 0)
1407 bb_perror_msg_and_die("pipe");
1408 nextout = pipefds[1];
1414 /* XXX test for failed fork()? */
1416 child->pid = fork();
1418 child->pid = vfork();
1421 /* Set the handling for job control signals back to the default. */
1422 signal(SIGINT, SIG_DFL);
1423 signal(SIGQUIT, SIG_DFL);
1424 signal(SIGTERM, SIG_DFL);
1425 signal(SIGTSTP, SIG_DFL);
1426 signal(SIGTTIN, SIG_DFL);
1427 signal(SIGTTOU, SIG_DFL);
1428 signal(SIGCHLD, SIG_DFL);
1440 if (pipefds[0] != -1) {
1441 close(pipefds[0]); /* opposite end of our output pipe */
1444 /* Like bash, explicit redirects override pipes,
1445 * and the pipe fd is available for dup'ing. */
1446 setup_redirects(child, NULL);
1448 if (interactive && pi->followup != PIPE_BG) {
1449 /* If we (the child) win the race, put ourselves in the process
1450 * group whose leader is the first process in this pipe. */
1452 pi->pgrp = getpid();
1454 if (setpgid(0, pi->pgrp) == 0) {
1455 tcsetpgrp(2, pi->pgrp);
1462 /* put our child in the process group whose leader is the
1463 first process in this pipe */
1465 pi->pgrp = child->pid;
1467 /* Don't check for errors. The child may be dead already,
1468 * in which case setpgid returns error code EACCES. */
1469 setpgid(child->pid, pi->pgrp);
1476 /* If there isn't another process, nextin is garbage
1477 but it doesn't matter */
1478 nextin = pipefds[0];
1483 static int run_list_real(struct pipe *pi)
1485 char *save_name = NULL;
1487 char **save_list = NULL;
1491 int rcode = 0, flag_skip = 1;
1492 int flag_restore = 0;
1493 int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
1494 reserved_style rmode, skip_more_in_this_rmode = RES_XXXX;
1495 /* check syntax for "for" */
1496 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1497 if ((rpipe->r_mode == RES_IN || rpipe->r_mode == RES_FOR)
1498 && (rpipe->next == NULL)
1503 if ((rpipe->r_mode == RES_IN && rpipe->next->r_mode == RES_IN && rpipe->next->progs->argv != NULL)
1504 || (rpipe->r_mode == RES_FOR && rpipe->next->r_mode != RES_IN)
1510 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1511 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL
1512 || pi->r_mode == RES_FOR
1521 debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n",
1522 rmode, if_code, next_if_code, skip_more_in_this_rmode);
1523 if (rmode == skip_more_in_this_rmode && flag_skip) {
1524 if (pi->followup == PIPE_SEQ)
1529 skip_more_in_this_rmode = RES_XXXX;
1530 if (rmode == RES_THEN || rmode == RES_ELSE)
1531 if_code = next_if_code;
1532 if (rmode == RES_THEN && if_code)
1534 if (rmode == RES_ELSE && !if_code)
1536 if (rmode == RES_ELIF && !if_code)
1538 if (rmode == RES_FOR && pi->num_progs) {
1540 /* if no variable values after "in" we skip "for" */
1541 if (!pi->next->progs->argv)
1543 /* create list of variable values */
1544 list = make_list_in(pi->next->progs->argv,
1545 pi->progs->argv[0]);
1547 save_name = pi->progs->argv[0];
1548 pi->progs->argv[0] = NULL;
1552 free(pi->progs->argv[0]);
1556 pi->progs->argv[0] = save_name;
1557 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1560 /* insert new value from list for variable */
1561 if (pi->progs->argv[0])
1562 free(pi->progs->argv[0]);
1563 pi->progs->argv[0] = *list++;
1564 pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
1567 if (rmode == RES_IN)
1569 if (rmode == RES_DO) {
1573 if ((rmode == RES_DONE)) {
1580 if (pi->num_progs == 0)
1582 save_num_progs = pi->num_progs; /* save number of programs */
1583 rcode = run_pipe_real(pi);
1584 debug_printf("run_pipe_real returned %d\n", rcode);
1586 /* We only ran a builtin: rcode was set by the return value
1587 * of run_pipe_real(), and we don't need to wait for anything. */
1588 } else if (pi->followup == PIPE_BG) {
1589 /* XXX check bash's behavior with nontrivial pipes */
1590 /* XXX compute jobid */
1591 /* XXX what does bash do with attempts to background builtins? */
1593 rcode = EXIT_SUCCESS;
1596 /* move the new process group into the foreground */
1597 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1598 bb_perror_msg("tcsetpgrp-3");
1599 rcode = checkjobs(pi);
1600 /* move the shell to the foreground */
1601 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1602 bb_perror_msg("tcsetpgrp-4");
1604 rcode = checkjobs(pi);
1606 debug_printf("checkjobs returned %d\n", rcode);
1608 last_return_code = rcode;
1609 pi->num_progs = save_num_progs; /* restore number of programs */
1610 if ( rmode == RES_IF || rmode == RES_ELIF )
1611 next_if_code = rcode; /* can be overwritten a number of times */
1612 if (rmode == RES_WHILE)
1613 flag_rep = !last_return_code;
1614 if (rmode == RES_UNTIL)
1615 flag_rep = last_return_code;
1616 if ((rcode == EXIT_SUCCESS && pi->followup == PIPE_OR)
1617 || (rcode != EXIT_SUCCESS && pi->followup == PIPE_AND)
1619 skip_more_in_this_rmode = rmode;
1626 /* return code is the exit status of the pipe */
1627 static int free_pipe(struct pipe *pi, int indent)
1630 struct child_prog *child;
1631 struct redir_struct *r, *rnext;
1632 int a, i, ret_code = 0;
1634 if (pi->stopped_progs > 0)
1636 final_printf("%s run pipe: (pid %d)\n", indenter(indent), getpid());
1637 for (i = 0; i < pi->num_progs; i++) {
1638 child = &pi->progs[i];
1639 final_printf("%s command %d:\n", indenter(indent), i);
1641 for (a = 0, p = child->argv; *p; a++, p++) {
1642 final_printf("%s argv[%d] = %s\n", indenter(indent), a, *p);
1644 globfree(&child->glob_result);
1646 } else if (child->group) {
1647 final_printf("%s begin group (subshell:%d)\n", indenter(indent), child->subshell);
1648 ret_code = free_pipe_list(child->group, indent+3);
1649 final_printf("%s end group\n", indenter(indent));
1651 final_printf("%s (nil)\n", indenter(indent));
1653 for (r = child->redirects; r; r = rnext) {
1654 final_printf("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip);
1656 /* guard against the case >$FOO, where foo is unset or blank */
1657 if (r->word.gl_pathv) {
1658 final_printf(" %s\n", *r->word.gl_pathv);
1662 final_printf("&%d\n", r->dup);
1667 child->redirects = NULL;
1669 free(pi->progs); /* children are an array, they get freed all at once */
1674 static int free_pipe_list(struct pipe *head, int indent)
1676 int rcode = 0; /* if list has no members */
1677 struct pipe *pi, *next;
1678 for (pi = head; pi; pi = next) {
1679 final_printf("%s pipe reserved mode %d\n", indenter(indent), pi->r_mode);
1680 rcode = free_pipe(pi, indent);
1681 final_printf("%s pipe followup code %d\n", indenter(indent), pi->followup);
1689 /* Select which version we will use */
1690 static int run_list(struct pipe *pi)
1693 if (fake_mode == 0) {
1694 rcode = run_list_real(pi);
1696 /* free_pipe_list has the side effect of clearing memory
1697 * In the long run that function can be merged with run_list_real,
1698 * but doing that now would hobble the debugging effort. */
1699 free_pipe_list(pi,0);
1703 /* The API for glob is arguably broken. This routine pushes a non-matching
1704 * string into the output structure, removing non-backslashed backslashes.
1705 * If someone can prove me wrong, by performing this function within the
1706 * original glob(3) api, feel free to rewrite this routine into oblivion.
1707 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
1708 * XXX broken if the last character is '\\', check that before calling.
1710 static int globhack(const char *src, int flags, glob_t *pglob)
1715 for (cnt = 1, s = src; s && *s; s++) {
1716 if (*s == '\\') s++;
1720 if (!dest) return GLOB_NOSPACE;
1721 if (!(flags & GLOB_APPEND)) {
1722 pglob->gl_pathv = NULL;
1723 pglob->gl_pathc = 0;
1727 pathc = ++pglob->gl_pathc;
1728 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
1729 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
1730 pglob->gl_pathv[pathc-1] = dest;
1731 pglob->gl_pathv[pathc] = NULL;
1732 for (s = src; s && *s; s++, dest++) {
1733 if (*s == '\\') s++;
1740 /* XXX broken if the last character is '\\', check that before calling */
1741 static int glob_needed(const char *s)
1744 if (*s == '\\') s++;
1745 if (strchr("*[?", *s)) return 1;
1750 static int xglob(o_string *dest, int flags, glob_t *pglob)
1754 /* short-circuit for null word */
1755 /* we can code this better when the debug_printf's are gone */
1756 if (dest->length == 0) {
1757 if (dest->nonnull) {
1758 /* bash man page calls this an "explicit" null */
1759 gr = globhack(dest->data, flags, pglob);
1760 debug_printf("globhack returned %d\n", gr);
1764 } else if (glob_needed(dest->data)) {
1765 gr = glob(dest->data, flags, NULL, pglob);
1766 debug_printf("glob returned %d\n", gr);
1767 if (gr == GLOB_NOMATCH) {
1768 /* quote removal, or more accurately, backslash removal */
1769 gr = globhack(dest->data, flags, pglob);
1770 debug_printf("globhack returned %d\n", gr);
1773 gr = globhack(dest->data, flags, pglob);
1774 debug_printf("globhack returned %d\n", gr);
1776 if (gr == GLOB_NOSPACE)
1777 bb_error_msg_and_die("out of memory during glob");
1778 if (gr != 0) { /* GLOB_ABORTED ? */
1779 bb_error_msg("glob(3) error %d", gr);
1781 /* globprint(glob_target); */
1785 /* This is used to get/check local shell variables */
1786 static const char *get_local_var(const char *s)
1788 struct variables *cur;
1792 for (cur = top_vars; cur; cur = cur->next)
1793 if (strcmp(cur->name, s) == 0)
1798 /* This is used to set local shell variables
1799 flg_export == 0 if only local (not exporting) variable
1800 flg_export == 1 if "new" exporting environ
1801 flg_export > 1 if current startup environ (not call putenv()) */
1802 static int set_local_var(const char *s, int flg_export)
1806 struct variables *cur;
1810 /* Assume when we enter this function that we are already in
1811 * NAME=VALUE format. So the first order of business is to
1812 * split 's' on the '=' into 'name' and 'value' */
1813 value = strchr(name, '=');
1814 /*if (value == 0 && ++value == 0) ??? -vda */
1815 if (value == NULL || value[1] == '\0') {
1821 for (cur = top_vars; cur; cur = cur->next) {
1822 if (strcmp(cur->name, name) == 0)
1827 if (strcmp(cur->value, value) == 0) {
1828 if (flg_export > 0 && cur->flg_export == 0)
1829 cur->flg_export = flg_export;
1832 } else if (cur->flg_read_only) {
1833 bb_error_msg("%s: readonly variable", name);
1836 if (flg_export > 0 || cur->flg_export > 1)
1837 cur->flg_export = 1;
1838 free((char*)cur->value);
1840 cur->value = strdup(value);
1843 cur = malloc(sizeof(struct variables));
1847 cur->name = strdup(name);
1852 struct variables *bottom = top_vars;
1853 cur->value = strdup(value);
1855 cur->flg_export = flg_export;
1856 cur->flg_read_only = 0;
1857 while (bottom->next)
1858 bottom = bottom->next;
1864 if (result == 0 && cur->flg_export == 1) {
1866 result = putenv(name);
1869 if (result > 0) /* equivalent to previous set */
1875 static void unset_local_var(const char *name)
1877 struct variables *cur;
1880 for (cur = top_vars; cur; cur = cur->next) {
1881 if (strcmp(cur->name, name) == 0)
1885 struct variables *next = top_vars;
1886 if (cur->flg_read_only) {
1887 bb_error_msg("%s: readonly variable", name);
1890 if (cur->flg_export)
1891 unsetenv(cur->name);
1892 free((char*)cur->name);
1893 free((char*)cur->value);
1894 while (next->next != cur)
1896 next->next = cur->next;
1902 static int is_assignment(const char *s)
1904 if (!s || !isalpha(*s))
1907 while (isalnum(*s) || *s == '_')
1912 /* the src parameter allows us to peek forward to a possible &n syntax
1913 * for file descriptor duplication, e.g., "2>&1".
1914 * Return code is 0 normally, 1 if a syntax error is detected in src.
1915 * Resource errors (in xmalloc) cause the process to exit */
1916 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
1917 struct in_str *input)
1919 struct child_prog *child = ctx->child;
1920 struct redir_struct *redir = child->redirects;
1921 struct redir_struct *last_redir = NULL;
1923 /* Create a new redir_struct and drop it onto the end of the linked list */
1926 redir = redir->next;
1928 redir = xmalloc(sizeof(struct redir_struct));
1930 redir->word.gl_pathv = NULL;
1932 last_redir->next = redir;
1934 child->redirects = redir;
1937 redir->type = style;
1938 redir->fd = (fd == -1) ? redir_table[style].default_fd : fd;
1940 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
1942 /* Check for a '2>&1' type redirect */
1943 redir->dup = redirect_dup_num(input);
1944 if (redir->dup == -2) return 1; /* syntax error */
1945 if (redir->dup != -1) {
1946 /* Erik had a check here that the file descriptor in question
1947 * is legit; I postpone that to "run time"
1948 * A "-" representation of "close me" shows up as a -3 here */
1949 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
1951 /* We do _not_ try to open the file that src points to,
1952 * since we need to return and let src be expanded first.
1953 * Set ctx->pending_redirect, so we know what to do at the
1954 * end of the next parsed word.
1956 ctx->pending_redirect = redir;
1961 static struct pipe *new_pipe(void) {
1963 pi = xmalloc(sizeof(struct pipe));
1967 pi->followup = 0; /* invalid */
1968 pi->r_mode = RES_NONE;
1972 static void initialize_context(struct p_context *ctx)
1975 ctx->pending_redirect = NULL;
1977 ctx->list_head = new_pipe();
1978 ctx->pipe = ctx->list_head;
1982 done_command(ctx); /* creates the memory for working child */
1985 /* normal return is 0
1986 * if a reserved word is found, and processed, return 1
1987 * should handle if, then, elif, else, fi, for, while, until, do, done.
1988 * case, function, and select are obnoxious, save those for later.
1990 static int reserved_word(o_string *dest, struct p_context *ctx)
1992 struct reserved_combo {
1993 const char *literal;
1997 /* Mostly a list of accepted follow-up reserved words.
1998 * FLAG_END means we are done with the sequence, and are ready
1999 * to turn the compound list into a command.
2000 * FLAG_START means the word must start a new compound list.
2002 static const struct reserved_combo reserved_list[] = {
2003 { "if", RES_IF, FLAG_THEN | FLAG_START },
2004 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2005 { "elif", RES_ELIF, FLAG_THEN },
2006 { "else", RES_ELSE, FLAG_FI },
2007 { "fi", RES_FI, FLAG_END },
2008 { "for", RES_FOR, FLAG_IN | FLAG_START },
2009 { "while", RES_WHILE, FLAG_DO | FLAG_START },
2010 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
2011 { "in", RES_IN, FLAG_DO },
2012 { "do", RES_DO, FLAG_DONE },
2013 { "done", RES_DONE, FLAG_END }
2015 const struct reserved_combo *r;
2016 #define NRES sizeof(reserved_list)/sizeof(reserved_list[0])
2018 for (r = reserved_list; r < reserved_list+NRES; r++) {
2019 if (strcmp(dest->data, r->literal) == 0) {
2020 debug_printf("found reserved word %s, code %d\n", r->literal, r->code);
2021 if (r->flag & FLAG_START) {
2022 struct p_context *new = xmalloc(sizeof(struct p_context));
2023 debug_printf("push stack\n");
2024 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2031 *new = *ctx; /* physical copy */
2032 initialize_context(ctx);
2034 } else if (ctx->w == RES_NONE || !(ctx->old_flag & (1 << r->code))) {
2041 ctx->old_flag = r->flag;
2042 if (ctx->old_flag & FLAG_END) {
2043 struct p_context *old;
2044 debug_printf("pop stack\n");
2045 done_pipe(ctx, PIPE_SEQ);
2047 old->child->group = ctx->list_head;
2048 old->child->subshell = 0;
2049 *ctx = *old; /* physical copy */
2059 /* normal return is 0.
2060 * Syntax or xglob errors return 1. */
2061 static int done_word(o_string *dest, struct p_context *ctx)
2063 struct child_prog *child = ctx->child;
2064 glob_t *glob_target;
2067 debug_printf("done_word: %s %p\n", dest->data, child);
2068 if (dest->length == 0 && !dest->nonnull) {
2069 debug_printf(" true null, ignored\n");
2072 if (ctx->pending_redirect) {
2073 glob_target = &ctx->pending_redirect->word;
2077 return 1; /* syntax error, groups and arglists don't mix */
2079 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2080 debug_printf("checking %s for reserved-ness\n", dest->data);
2081 if (reserved_word(dest, ctx))
2082 return (ctx->w == RES_SNTX);
2084 glob_target = &child->glob_result;
2085 if (child->argv) flags |= GLOB_APPEND;
2087 gr = xglob(dest, flags, glob_target);
2088 if (gr != 0) return 1;
2091 if (ctx->pending_redirect) {
2092 ctx->pending_redirect = NULL;
2093 if (glob_target->gl_pathc != 1) {
2094 bb_error_msg("ambiguous redirect");
2098 child->argv = glob_target->gl_pathv;
2100 if (ctx->w == RES_FOR) {
2101 done_word(dest, ctx);
2102 done_pipe(ctx, PIPE_SEQ);
2107 /* The only possible error here is out of memory, in which case
2109 static int done_command(struct p_context *ctx)
2111 /* The child is really already in the pipe structure, so
2112 * advance the pipe counter and make a new, null child.
2113 * Only real trickiness here is that the uncommitted
2114 * child structure, to which ctx->child points, is not
2115 * counted in pi->num_progs. */
2116 struct pipe *pi = ctx->pipe;
2117 struct child_prog *prog = ctx->child;
2119 if (prog && prog->group == NULL
2120 && prog->argv == NULL
2121 && prog->redirects == NULL) {
2122 debug_printf("done_command: skipping null command\n");
2126 debug_printf("done_command: num_progs incremented to %d\n", pi->num_progs);
2128 debug_printf("done_command: initializing\n");
2130 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2132 prog = pi->progs + pi->num_progs;
2133 prog->redirects = NULL;
2135 prog->is_stopped = 0;
2137 prog->glob_result.gl_pathv = NULL;
2141 prog->type = ctx->type;
2143 /* but ctx->pipe and ctx->list_head remain unchanged */
2147 static int done_pipe(struct p_context *ctx, pipe_style type)
2150 done_command(ctx); /* implicit closure of previous command */
2151 debug_printf("done_pipe, type %d\n", type);
2152 ctx->pipe->followup = type;
2153 ctx->pipe->r_mode = ctx->w;
2155 ctx->pipe->next = new_p;
2158 done_command(ctx); /* set up new pipe to accept commands */
2162 /* peek ahead in the in_str to find out if we have a "&n" construct,
2163 * as in "2>&1", that represents duplicating a file descriptor.
2164 * returns either -2 (syntax error), -1 (no &), or the number found.
2166 static int redirect_dup_num(struct in_str *input)
2168 int ch, d = 0, ok = 0;
2170 if (ch != '&') return -1;
2172 b_getch(input); /* get the & */
2176 return -3; /* "-" represents "close me" */
2178 while (isdigit(ch)) {
2186 bb_error_msg("ambiguous redirect");
2190 /* If a redirect is immediately preceded by a number, that number is
2191 * supposed to tell which file descriptor to redirect. This routine
2192 * looks for such preceding numbers. In an ideal world this routine
2193 * needs to handle all the following classes of redirects...
2194 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2195 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2196 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2197 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2198 * A -1 output from this program means no valid number was found, so the
2199 * caller should use the appropriate default for this redirection.
2201 static int redirect_opt_num(o_string *o)
2207 for (num = 0; num < o->length; num++) {
2208 if (!isdigit(*(o->data + num))) {
2212 /* reuse num (and save an int) */
2213 num = atoi(o->data);
2218 static FILE *generate_stream_from_list(struct pipe *head)
2221 int pid, channel[2];
2222 if (pipe(channel) < 0) bb_perror_msg_and_die("pipe");
2229 bb_perror_msg_and_die("fork");
2230 } else if (pid == 0) {
2232 if (channel[1] != 1) {
2236 _exit(run_list_real(head)); /* leaks memory */
2238 debug_printf("forked child %d\n", pid);
2240 pf = fdopen(channel[0],"r");
2241 debug_printf("pipe on FILE *%p\n", pf);
2245 /* this version hacked for testing purposes */
2246 /* return code is exit status of the process that is run. */
2247 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2250 o_string result = NULL_O_STRING;
2251 struct p_context inner;
2253 struct in_str pipe_str;
2254 initialize_context(&inner);
2256 /* recursion to generate command */
2257 retcode = parse_stream(&result, &inner, input, subst_end);
2258 if (retcode != 0) return retcode; /* syntax error or EOF */
2259 done_word(&result, &inner);
2260 done_pipe(&inner, PIPE_SEQ);
2263 p = generate_stream_from_list(inner.list_head);
2264 if (p == NULL) return 1;
2265 mark_open(fileno(p));
2266 setup_file_in_str(&pipe_str, p);
2268 /* now send results of command back into original context */
2269 retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2270 /* XXX In case of a syntax error, should we try to kill the child?
2271 * That would be tough to do right, so just read until EOF. */
2273 while (b_getch(&pipe_str) != EOF)
2277 debug_printf("done reading from pipe, pclose()ing\n");
2278 /* This is the step that wait()s for the child. Should be pretty
2279 * safe, since we just read an EOF from its stdout. We could try
2280 * to better, by using wait(), and keeping track of background jobs
2281 * at the same time. That would be a lot of work, and contrary
2282 * to the KISS philosophy of this program. */
2283 mark_closed(fileno(p));
2284 retcode = pclose(p);
2285 free_pipe_list(inner.list_head, 0);
2286 debug_printf("pclosed, retcode=%d\n", retcode);
2287 /* XXX this process fails to trim a single trailing newline */
2291 static int parse_group(o_string *dest, struct p_context *ctx,
2292 struct in_str *input, int ch)
2294 int rcode, endch = 0;
2295 struct p_context sub;
2296 struct child_prog *child = ctx->child;
2299 return 1; /* syntax error, groups and arglists don't mix */
2301 initialize_context(&sub);
2305 child->subshell = 1;
2311 syntax(); /* really logic error */
2313 rcode = parse_stream(dest, &sub, input, endch);
2314 done_word(dest, &sub); /* finish off the final word in the subcontext */
2315 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2316 child->group = sub.list_head;
2318 /* child remains "open", available for possible redirects */
2321 /* basically useful version until someone wants to get fancier,
2322 * see the bash man page under "Parameter Expansion" */
2323 static const char *lookup_param(const char *src)
2325 const char *p = NULL;
2329 p = get_local_var(src);
2334 /* return code: 0 for OK, 1 for syntax error */
2335 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2339 int ch = input->peek(input); /* first character after the $ */
2340 debug_printf("handle_dollar: ch=%c\n", ch);
2342 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2344 while (ch = b_peek(input), isalnum(ch) || ch == '_') {
2348 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2349 } else if (isdigit(ch)) {
2350 i = ch-'0'; /* XXX is $0 special? */
2351 if (i < global_argc) {
2352 parse_string(dest, ctx, global_argv[i]); /* recursion */
2355 } else switch (ch) {
2357 b_adduint(dest, getpid());
2361 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2365 b_adduint(dest, last_return_code);
2369 b_adduint(dest, global_argc ? global_argc-1 : 0);
2373 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2376 /* XXX maybe someone will try to escape the '}' */
2378 ch = b_getch(input);
2379 if (ch == EOF || ch == '}')
2387 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2391 process_command_subs(dest, ctx, input, ')');
2395 for (i = 1; i < global_argc; i++) {
2396 parse_string(dest, ctx, global_argv[i]);
2397 if (i+1 < global_argc)
2398 parse_string(dest, ctx, sep);
2404 /* still unhandled, but should be eventually */
2405 bb_error_msg("unhandled syntax: $%c", ch);
2409 b_addqchr(dest,'$', dest->quote);
2411 /* Eat the character if the flag was set. If the compiler
2412 * is smart enough, we could substitute "b_getch(input);"
2413 * for all the "advance = 1;" above, and also end up with
2414 * a nice size-optimized program. Hah! That'll be the day.
2416 if (advance) b_getch(input);
2420 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2423 setup_string_in_str(&foo, src);
2424 return parse_stream(dest, ctx, &foo, '\0');
2427 /* return code is 0 for normal exit, 1 for syntax error */
2428 int parse_stream(o_string *dest, struct p_context *ctx,
2429 struct in_str *input, int end_trigger)
2433 redir_type redir_style;
2436 /* Only double-quote state is handled in the state variable dest->quote.
2437 * A single-quote triggers a bypass of the main loop until its mate is
2438 * found. When recursing, quote state is passed in via dest->quote. */
2440 debug_printf("parse_stream, end_trigger=%d\n", end_trigger);
2441 while ((ch = b_getch(input)) != EOF) {
2443 next = (ch == '\n') ? 0 : b_peek(input);
2444 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
2445 ch, ch, m, dest->quote);
2446 if (m == 0 || ((m == 1 || m == 2) && dest->quote)) {
2447 b_addqchr(dest, ch, dest->quote);
2450 if (m == 2) { /* unquoted IFS */
2451 if (done_word(dest, ctx)) {
2454 /* If we aren't performing a substitution, treat a newline as a
2455 * command separator. */
2456 if (end_trigger != '\0' && ch == '\n')
2457 done_pipe(ctx, PIPE_SEQ);
2459 if (ch == end_trigger && !dest->quote && ctx->w == RES_NONE) {
2460 debug_printf("leaving parse_stream (triggered)\n");
2467 if (dest->length == 0 && !dest->quote) {
2470 if (ch == EOF || ch == '\n')
2475 b_addqchr(dest, ch, dest->quote);
2483 b_addqchr(dest, '\\', dest->quote);
2484 b_addqchr(dest, b_getch(input), dest->quote);
2487 if (handle_dollar(dest, ctx, input) != 0) return 1;
2492 ch = b_getch(input);
2493 if (ch == EOF || ch == '\'')
2504 dest->quote = !dest->quote;
2507 process_command_subs(dest, ctx, input, '`');
2510 redir_fd = redirect_opt_num(dest);
2511 done_word(dest, ctx);
2512 redir_style = REDIRECT_OVERWRITE;
2514 redir_style = REDIRECT_APPEND;
2516 } else if (next == '(') {
2517 syntax(); /* until we support >(list) Process Substitution */
2520 setup_redirect(ctx, redir_fd, redir_style, input);
2523 redir_fd = redirect_opt_num(dest);
2524 done_word(dest, ctx);
2525 redir_style = REDIRECT_INPUT;
2527 redir_style = REDIRECT_HEREIS;
2529 } else if (next == '>') {
2530 redir_style = REDIRECT_IO;
2532 } else if (next == '(') {
2533 syntax(); /* until we support <(list) Process Substitution */
2536 setup_redirect(ctx, redir_fd, redir_style, input);
2539 done_word(dest, ctx);
2540 done_pipe(ctx, PIPE_SEQ);
2543 done_word(dest, ctx);
2546 done_pipe(ctx, PIPE_AND);
2548 done_pipe(ctx, PIPE_BG);
2552 done_word(dest, ctx);
2555 done_pipe(ctx, PIPE_OR);
2557 /* we could pick up a file descriptor choice here
2558 * with redirect_opt_num(), but bash doesn't do it.
2559 * "echo foo 2| cat" yields "foo 2". */
2565 if (parse_group(dest, ctx, input, ch) != 0)
2570 syntax(); /* Proper use of this character caught by end_trigger */
2573 syntax(); /* this is really an internal logic error */
2577 /* complain if quote? No, maybe we just finished a command substitution
2578 * that was quoted. Example:
2579 * $ echo "`cat foo` plus more"
2580 * and we just got the EOF generated by the subshell that ran "cat foo"
2581 * The only real complaint is if we got an EOF when end_trigger != '\0',
2582 * that is, we were really supposed to get end_trigger, and never got
2583 * one before the EOF. Can't use the standard "syntax error" return code,
2584 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
2585 debug_printf("leaving parse_stream (EOF)\n");
2586 if (end_trigger != '\0')
2591 static void mapset(const char *set, int code)
2594 map[(unsigned char)*set++] = code;
2597 static void update_ifs_map(void)
2599 /* char *ifs and char map[256] are both globals. */
2600 ifs = getenv("IFS");
2601 if (ifs == NULL) ifs = " \t\n";
2602 /* Precompute a list of 'flow through' behavior so it can be treated
2603 * quickly up front. Computation is necessary because of IFS.
2604 * Special case handling of IFS == " \t\n" is not implemented.
2605 * The map[] array only really needs two bits each, and on most machines
2606 * that would be faster because of the reduced L1 cache footprint.
2608 memset(map, 0, sizeof(map)); /* most characters flow through always */
2609 mapset("\\$'\"`", 3); /* never flow through */
2610 mapset("<>;&|(){}#", 1); /* flow through if quoted */
2611 mapset(ifs, 2); /* also flow through if quoted */
2614 /* most recursion does not come through here, the exception is
2615 * from builtin_source() */
2616 int parse_stream_outer(struct in_str *inp, int flag)
2618 struct p_context ctx;
2619 o_string temp = NULL_O_STRING;
2623 initialize_context(&ctx);
2625 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
2626 inp->promptmode = 1;
2627 rcode = parse_stream(&temp, &ctx, inp, '\n');
2628 if (rcode != 1 && ctx.old_flag != 0) {
2631 if (rcode != 1 && ctx.old_flag == 0) {
2632 done_word(&temp, &ctx);
2633 done_pipe(&ctx, PIPE_SEQ);
2634 run_list(ctx.list_head);
2636 if (ctx.old_flag != 0) {
2643 free_pipe_list(ctx.list_head,0);
2646 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
2650 static int parse_string_outer(const char *s, int flag)
2652 struct in_str input;
2653 setup_string_in_str(&input, s);
2654 return parse_stream_outer(&input, flag);
2657 static int parse_file_outer(FILE *f)
2660 struct in_str input;
2661 setup_file_in_str(&input, f);
2662 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
2666 /* Make sure we have a controlling tty. If we get started under a job
2667 * aware app (like bash for example), make sure we are now in charge so
2668 * we don't fight over who gets the foreground */
2669 static void setup_job_control(void)
2671 /*static --why?? */ pid_t shell_pgrp;
2673 /* Loop until we are in the foreground. */
2674 while (tcgetpgrp(shell_terminal) != (shell_pgrp = getpgrp()))
2675 kill(- shell_pgrp, SIGTTIN);
2677 /* Ignore interactive and job-control signals. */
2678 signal(SIGINT, SIG_IGN);
2679 signal(SIGQUIT, SIG_IGN);
2680 signal(SIGTERM, SIG_IGN);
2681 signal(SIGTSTP, SIG_IGN);
2682 signal(SIGTTIN, SIG_IGN);
2683 signal(SIGTTOU, SIG_IGN);
2684 signal(SIGCHLD, SIG_IGN);
2686 /* Put ourselves in our own process group. */
2688 shell_pgrp = getpid();
2689 setpgid(shell_pgrp, shell_pgrp);
2691 /* Grab control of the terminal. */
2692 tcsetpgrp(shell_terminal, shell_pgrp);
2695 int hush_main(int argc, char **argv);
2696 int hush_main(int argc, char **argv)
2702 #if ENABLE_FEATURE_EDITING
2703 line_input_state = new_line_input_t(FOR_SHELL);
2706 /* XXX what should these be while sourcing /etc/profile? */
2710 /* (re?) initialize globals. Sometimes hush_main() ends up calling
2711 * hush_main(), therefore we cannot rely on the BSS to zero out this
2712 * stuff. Reset these to 0 every time. */
2714 /* map[] is taken care of with call to update_ifs_map() */
2717 close_me_head = NULL;
2722 /* Initialize some more globals to non-zero values */
2724 if (ENABLE_FEATURE_EDITING)
2725 cmdedit_set_initial_prompt();
2729 /* initialize our shell local variables with the values
2730 * currently living in the environment */
2734 set_local_var(*e++, 2); /* without call putenv() */
2736 last_return_code = EXIT_SUCCESS;
2738 if (argv[0] && argv[0][0] == '-') {
2739 debug_printf("\nsourcing /etc/profile\n");
2740 input = fopen("/etc/profile", "r");
2741 if (input != NULL) {
2742 mark_open(fileno(input));
2743 parse_file_outer(input);
2744 mark_closed(fileno(input));
2750 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
2753 global_argv = argv+optind;
2754 global_argc = argc-optind;
2755 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
2765 fprintf(stderr, "Usage: sh [FILE]...\n"
2766 " or: sh -c command [args]...\n\n");
2773 /* A shell is interactive if the '-i' flag was given, or if all of
2774 * the following conditions are met:
2776 * no arguments remaining or the -s flag given
2777 * standard input is a terminal
2778 * standard output is a terminal
2779 * Refer to Posix.2, the description of the 'sh' utility. */
2780 if (argv[optind] == NULL && input == stdin
2781 && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
2786 debug_printf("\ninteractive=%d\n", interactive);
2788 /* Looks like they want an interactive shell */
2789 #if !ENABLE_FEATURE_SH_EXTRA_QUIET
2790 printf( "\n\n%s hush - the humble shell v0.01 (testing)\n",
2792 printf( "Enter 'help' for a list of built-in commands.\n\n");
2794 setup_job_control();
2797 if (argv[optind] == NULL) {
2798 opt = parse_file_outer(stdin);
2802 debug_printf("\nrunning script '%s'\n", argv[optind]);
2803 global_argv = argv + optind;
2804 global_argc = argc - optind;
2805 input = xfopen(argv[optind], "r");
2806 opt = parse_file_outer(input);
2808 #if ENABLE_FEATURE_CLEAN_UP
2810 if (cwd != bb_msg_unknown)
2813 struct variables *cur, *tmp;
2814 for (cur = top_vars; cur; cur = tmp) {
2816 if (!cur->flg_read_only) {
2817 free((char*)cur->name);
2818 free((char*)cur->value);
2826 return opt ? opt : last_return_code;
2829 static char *insert_var_value(char *inp)
2831 int res_str_len = 0;
2834 char *p, *res_str = NULL;
2837 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
2840 res_str = xrealloc(res_str, (res_str_len + len));
2841 strncpy((res_str + res_str_len), inp, len);
2845 p = strchr(inp, SPECIAL_VAR_SYMBOL);
2847 p1 = lookup_param(inp);
2849 len = res_str_len + strlen(p1);
2850 res_str = xrealloc(res_str, (1 + len));
2851 strcpy((res_str + res_str_len), p1);
2854 *p = SPECIAL_VAR_SYMBOL;
2859 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
2860 strcpy((res_str + res_str_len), inp);
2861 while ((p = strchr(res_str, '\n'))) {
2865 return (res_str == NULL) ? inp : res_str;
2868 static char **make_list_in(char **inp, char *name)
2871 int name_len = strlen(name);
2876 /* create list of variable values */
2877 list = xmalloc(sizeof(*list));
2878 for (i = 0; inp[i]; i++) {
2879 p3 = insert_var_value(inp[i]);
2886 p2 = strchr(p1, ' ');
2893 /* we use n + 2 in realloc for list, because we add
2894 * new element and then we will add NULL element */
2895 list = xrealloc(list, sizeof(*list) * (n + 2));
2896 list[n] = xmalloc(2 + name_len + len);
2897 strcpy(list[n], name);
2898 strcat(list[n], "=");
2899 strncat(list[n], p1, len);
2900 list[n++][name_len + len + 1] = '\0';
2903 if (p3 != inp[i]) free(p3);
2909 /* Make new string for parser */
2910 static char* make_string(char ** inp)
2917 for (n = 0; inp[n]; n++) {
2918 p = insert_var_value(inp[n]);
2919 str = xrealloc(str, (len + strlen(p)));
2926 len = strlen(str) + 3;
2927 if (p != inp[n]) free(p);