2 * sh.c -- a prototype Bourne shell grammar parser
3 * Intended to follow the original Thompson and Ritchie
4 * "small and simple is beautiful" philosophy, which
5 * incidentally is a good match to today's BusyBox.
7 * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
10 * The parser routines proper are all original material, first
11 * written Dec 2000 and Jan 2001 by Larry Doolittle.
12 * The execution engine, the builtins, and much of the underlying
13 * support has been adapted from busybox-0.49pre's lash,
14 * which is Copyright (C) 2000 by Lineo, Inc., and
15 * written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
16 * That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
17 * Erik W. Troan, which they placed in the public domain. I don't know
18 * how much of the Johnson/Troan code has survived the repeated rewrites.
20 * b_addchr() derived from similar w_addchar function in glibc-2.2
21 * setup_redirect(), redirect_opt_num(), and big chunks of main()
22 * and many builtins derived from contributions by Erik Andersen
23 * miscellaneous bugfixes from Matt Kraai
25 * There are two big (and related) architecture differences between
26 * this parser and the lash parser. One is that this version is
27 * actually designed from the ground up to understand nearly all
28 * of the Bourne grammar. The second, consequential change is that
29 * the parser and input reader have been turned inside out. Now,
30 * the parser is in control, and asks for input as needed. The old
31 * way had the input reader in control, and it asked for parsing to
32 * take place as needed. The new way makes it much easier to properly
33 * handle the recursion implicit in the various substitutions, especially
34 * across continuation lines.
36 * Bash grammar not implemented: (how many of these were in original sh?)
37 * $@ (those sure look like weird quoting rules)
39 * ! negation operator for pipes
40 * &> and >& redirection of stdout+stderr
43 * fancy forms of Parameter Expansion
45 * Arithmetic Expansion
46 * <(list) and >(list) Process Substitution
47 * reserved words: case, esac, select, function
48 * Here Documents ( << word )
51 * job handling woefully incomplete and buggy
52 * reserved word execution woefully incomplete and buggy
54 * port selected bugfixes from post-0.49 busybox lash - done?
55 * finish implementing reserved words: for, while, until, do, done
56 * change { and } from special chars to reserved words
57 * builtins: break, continue, eval, return, set, trap, ulimit
59 * handle children going into background
60 * clean up recognition of null pipes
61 * check setting of global_argc and global_argv
62 * control-C handling, probably with longjmp
63 * follow IFS rules more precisely, including update semantics
64 * figure out what to do with backslash-newline
65 * explain why we use signal instead of sigaction
66 * propagate syntax errors, die on resource errors?
67 * continuation lines, both explicit and implicit - done?
68 * memory leak finding and plugging - done?
69 * more testing, especially quoting rules and redirection
70 * document how quoting rules not precisely followed for variable assignments
71 * maybe change map[] to use 2-bit entries
72 * (eventually) remove all the printf's
74 * This program is free software; you can redistribute it and/or modify
75 * it under the terms of the GNU General Public License as published by
76 * the Free Software Foundation; either version 2 of the License, or
77 * (at your option) any later version.
79 * This program is distributed in the hope that it will be useful,
80 * but WITHOUT ANY WARRANTY; without even the implied warranty of
81 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
82 * General Public License for more details.
84 * You should have received a copy of the GNU General Public License
85 * along with this program; if not, write to the Free Software
86 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
90 #include <malloc.h> /* malloc, free, realloc*/
91 #include <linux/ctype.h> /* isalpha, isdigit */
92 #include <common.h> /* readline */
94 #include <command.h> /* find_cmd */
97 #include <ctype.h> /* isalpha, isdigit */
98 #include <unistd.h> /* getpid */
99 #include <stdlib.h> /* getenv, atoi */
100 #include <string.h> /* strchr */
101 #include <stdio.h> /* popen etc. */
102 #include <glob.h> /* glob, of course */
103 #include <stdarg.h> /* va_list */
106 #include <getopt.h> /* should be pretty obvious */
108 #include <sys/stat.h> /* ulimit */
109 #include <sys/types.h>
110 #include <sys/wait.h>
113 /* #include <dmalloc.h> */
119 #define applet_name "hush"
120 #include "standalone.h"
121 #define hush_main main
122 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
126 #define SPECIAL_VAR_SYMBOL 03
128 #define FLAG_EXIT_FROM_LOOP 1
129 #define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
130 #define FLAG_REPARSING (1 << 2) /* >= 2nd pass */
135 DECLARE_GLOBAL_DATA_PTR;
137 #define EXIT_SUCCESS 0
139 #define syntax() syntax_err()
140 #define xstrdup strdup
141 #define error_msg printf
145 REDIRECT_OVERWRITE = 2,
151 /* The descrip member of this structure is only used to make debugging
153 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
155 { O_RDONLY, 0, "<" },
156 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
157 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
158 { O_RDONLY, -1, "<<" },
170 /* might eventually control execution */
187 #define FLAG_END (1<<RES_NONE)
188 #define FLAG_IF (1<<RES_IF)
189 #define FLAG_THEN (1<<RES_THEN)
190 #define FLAG_ELIF (1<<RES_ELIF)
191 #define FLAG_ELSE (1<<RES_ELSE)
192 #define FLAG_FI (1<<RES_FI)
193 #define FLAG_FOR (1<<RES_FOR)
194 #define FLAG_WHILE (1<<RES_WHILE)
195 #define FLAG_UNTIL (1<<RES_UNTIL)
196 #define FLAG_DO (1<<RES_DO)
197 #define FLAG_DONE (1<<RES_DONE)
198 #define FLAG_IN (1<<RES_IN)
199 #define FLAG_START (1<<RES_XXXX)
201 /* This holds pointers to the various results of parsing */
203 struct child_prog *child;
204 struct pipe *list_head;
207 struct redir_struct *pending_redirect;
210 int old_flag; /* for figuring out valid reserved words */
211 struct p_context *stack;
212 int type; /* define type of parser : ";$" common or special symbol */
213 /* How about quoting status? */
217 struct redir_struct {
218 redir_type type; /* type of redirection */
219 int fd; /* file descriptor being redirected */
220 int dup; /* -1, or file descriptor being duplicated */
221 struct redir_struct *next; /* pointer to the next redirect in the list */
222 glob_t word; /* *word.gl_pathv is the filename */
228 pid_t pid; /* 0 if exited */
230 char **argv; /* program name and arguments */
232 int argc; /* number of program arguments */
234 struct pipe *group; /* if non-NULL, first in group or subshell */
236 int subshell; /* flag, non-zero if group must be forked */
237 struct redir_struct *redirects; /* I/O redirections */
238 glob_t glob_result; /* result of parameter globbing */
239 int is_stopped; /* is the program currently running? */
240 struct pipe *family; /* pointer back to the child's parent pipe */
242 int sp; /* number of SPECIAL_VAR_SYMBOL */
248 int jobid; /* job number */
250 int num_progs; /* total number of programs in job */
252 int running_progs; /* number of programs running */
253 char *text; /* name of job */
254 char *cmdbuf; /* buffer various argv's point into */
255 pid_t pgrp; /* process group ID for the job */
257 struct child_prog *progs; /* array of commands in pipe */
258 struct pipe *next; /* to track background commands */
260 int stopped_progs; /* number of programs alive, but stopped */
261 int job_context; /* bitmask defining current context */
263 pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
264 reserved_style r_mode; /* supports if, for, while, until */
270 struct close_me *next;
279 struct variables *next;
282 /* globals, connect us to the outside world
283 * the first three support $?, $#, and $1 */
286 unsigned int global_argc;
288 unsigned int last_return_code;
291 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
294 /* "globals" within this file */
296 static char map[256];
298 static int fake_mode;
299 static int interactive;
300 static struct close_me *close_me_head;
301 static const char *cwd;
302 static struct pipe *job_list;
303 static unsigned int last_bg_pid;
304 static unsigned int last_jobid;
305 static unsigned int shell_terminal;
308 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
309 struct variables *top_vars = &shell_ver;
311 static int flag_repeat = 0;
312 static int do_repeat = 0;
313 static struct variables *top_vars = NULL ;
314 #endif /*__U_BOOT__ */
316 #define B_CHUNK (100)
326 #define NULL_O_STRING {NULL,0,0,0,0}
327 /* used for initialization:
328 o_string foo = NULL_O_STRING; */
330 /* I can almost use ordinary FILE *. Is open_memstream() universally
331 * available? Where is it documented? */
342 int (*get) (struct in_str *);
343 int (*peek) (struct in_str *);
345 #define b_getch(input) ((input)->get(input))
346 #define b_peek(input) ((input)->peek(input))
349 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
351 struct built_in_command {
352 char *cmd; /* name */
353 char *descr; /* description */
354 int (*function) (struct child_prog *); /* function ptr */
358 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
363 /* This should be in utility.c */
366 static void debug_printf(const char *format, ...)
369 va_start(args, format);
370 vfprintf(stderr, format, args);
374 #define debug_printf(fmt,args...) printf (fmt ,##args)
377 static inline void debug_printf(const char *format, ...) { }
379 #define final_printf debug_printf
382 static void syntax_err(void) {
383 printf("syntax error\n");
386 static void __syntax(char *file, int line) {
387 error_msg("syntax error %s:%d", file, line);
389 #define syntax() __syntax(__FILE__, __LINE__)
393 static void *xmalloc(size_t size);
394 static void *xrealloc(void *ptr, size_t size);
396 /* Index of subroutines: */
397 /* function prototypes for builtins */
398 static int builtin_cd(struct child_prog *child);
399 static int builtin_env(struct child_prog *child);
400 static int builtin_eval(struct child_prog *child);
401 static int builtin_exec(struct child_prog *child);
402 static int builtin_exit(struct child_prog *child);
403 static int builtin_export(struct child_prog *child);
404 static int builtin_fg_bg(struct child_prog *child);
405 static int builtin_help(struct child_prog *child);
406 static int builtin_jobs(struct child_prog *child);
407 static int builtin_pwd(struct child_prog *child);
408 static int builtin_read(struct child_prog *child);
409 static int builtin_set(struct child_prog *child);
410 static int builtin_shift(struct child_prog *child);
411 static int builtin_source(struct child_prog *child);
412 static int builtin_umask(struct child_prog *child);
413 static int builtin_unset(struct child_prog *child);
414 static int builtin_not_written(struct child_prog *child);
416 /* o_string manipulation: */
417 static int b_check_space(o_string *o, int len);
418 static int b_addchr(o_string *o, int ch);
419 static void b_reset(o_string *o);
420 static int b_addqchr(o_string *o, int ch, int quote);
422 static int b_adduint(o_string *o, unsigned int i);
424 /* in_str manipulations: */
425 static int static_get(struct in_str *i);
426 static int static_peek(struct in_str *i);
427 static int file_get(struct in_str *i);
428 static int file_peek(struct in_str *i);
430 static void setup_file_in_str(struct in_str *i, FILE *f);
432 static void setup_file_in_str(struct in_str *i);
434 static void setup_string_in_str(struct in_str *i, const char *s);
436 /* close_me manipulations: */
437 static void mark_open(int fd);
438 static void mark_closed(int fd);
439 static void close_all(void);
441 /* "run" the final data structures: */
442 static char *indenter(int i);
443 static int free_pipe_list(struct pipe *head, int indent);
444 static int free_pipe(struct pipe *pi, int indent);
445 /* really run the final data structures: */
447 static int setup_redirects(struct child_prog *prog, int squirrel[]);
449 static int run_list_real(struct pipe *pi);
451 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
453 static int run_pipe_real(struct pipe *pi);
454 /* extended glob support: */
456 static int globhack(const char *src, int flags, glob_t *pglob);
457 static int glob_needed(const char *s);
458 static int xglob(o_string *dest, int flags, glob_t *pglob);
460 /* variable assignment: */
461 static int is_assignment(const char *s);
462 /* data structure manipulation: */
464 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
466 static void initialize_context(struct p_context *ctx);
467 static int done_word(o_string *dest, struct p_context *ctx);
468 static int done_command(struct p_context *ctx);
469 static int done_pipe(struct p_context *ctx, pipe_style type);
470 /* primary string parsing: */
472 static int redirect_dup_num(struct in_str *input);
473 static int redirect_opt_num(o_string *o);
474 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
475 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
477 static char *lookup_param(char *src);
478 static char *make_string(char **inp);
479 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
481 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
483 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
485 static int parse_stream_outer(struct in_str *inp, int flag);
487 static int parse_string_outer(const char *s, int flag);
488 static int parse_file_outer(FILE *f);
491 /* job management: */
492 static int checkjobs(struct pipe* fg_pipe);
493 static void insert_bg_job(struct pipe *pi);
494 static void remove_bg_job(struct pipe *pi);
496 /* local variable support */
497 static char **make_list_in(char **inp, char *name);
498 static char *insert_var_value(char *inp);
501 /* Table of built-in functions. They can be forked or not, depending on
502 * context: within pipes, they fork. As simple commands, they do not.
503 * When used in non-forking context, they can change global variables
504 * in the parent shell process. If forked, of course they can not.
505 * For example, 'unset foo | whatever' will parse and run, but foo will
506 * still be set at the end. */
507 static struct built_in_command bltins[] = {
508 {"bg", "Resume a job in the background", builtin_fg_bg},
509 {"break", "Exit for, while or until loop", builtin_not_written},
510 {"cd", "Change working directory", builtin_cd},
511 {"continue", "Continue for, while or until loop", builtin_not_written},
512 {"env", "Print all environment variables", builtin_env},
513 {"eval", "Construct and run shell command", builtin_eval},
514 {"exec", "Exec command, replacing this shell with the exec'd process",
516 {"exit", "Exit from shell()", builtin_exit},
517 {"export", "Set environment variable", builtin_export},
518 {"fg", "Bring job into the foreground", builtin_fg_bg},
519 {"jobs", "Lists the active jobs", builtin_jobs},
520 {"pwd", "Print current directory", builtin_pwd},
521 {"read", "Input environment variable", builtin_read},
522 {"return", "Return from a function", builtin_not_written},
523 {"set", "Set/unset shell local variables", builtin_set},
524 {"shift", "Shift positional parameters", builtin_shift},
525 {"trap", "Trap signals", builtin_not_written},
526 {"ulimit","Controls resource limits", builtin_not_written},
527 {"umask","Sets file creation mask", builtin_umask},
528 {"unset", "Unset environment variable", builtin_unset},
529 {".", "Source-in and run commands in a file", builtin_source},
530 {"help", "List shell built-in commands", builtin_help},
534 static const char *set_cwd(void)
537 cwd = NULL; /* xgetcwd(arg) called free(arg) */
538 cwd = xgetcwd((char *)cwd);
544 /* built-in 'eval' handler */
545 static int builtin_eval(struct child_prog *child)
548 int rcode = EXIT_SUCCESS;
550 if (child->argv[1]) {
551 str = make_string(child->argv + 1);
552 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
553 FLAG_PARSE_SEMICOLON);
555 rcode = last_return_code;
560 /* built-in 'cd <path>' handler */
561 static int builtin_cd(struct child_prog *child)
564 if (child->argv[1] == NULL)
565 newdir = getenv("HOME");
567 newdir = child->argv[1];
569 printf("cd: %s: %s\n", newdir, strerror(errno));
576 /* built-in 'env' handler */
577 static int builtin_env(struct child_prog *dummy)
580 if (e == NULL) return EXIT_FAILURE;
587 /* built-in 'exec' handler */
588 static int builtin_exec(struct child_prog *child)
590 if (child->argv[1] == NULL)
591 return EXIT_SUCCESS; /* Really? */
597 /* built-in 'exit' handler */
598 static int builtin_exit(struct child_prog *child)
600 if (child->argv[1] == NULL)
601 exit(last_return_code);
602 exit (atoi(child->argv[1]));
605 /* built-in 'export VAR=value' handler */
606 static int builtin_export(struct child_prog *child)
609 char *name = child->argv[1];
612 return (builtin_env(child));
618 char *value = strchr(name, '=');
622 /* They are exporting something without an =VALUE */
624 value = get_local_var(name);
626 size_t ln = strlen(name);
628 tmp = realloc(name, ln+strlen(value)+2);
632 sprintf(tmp+ln, "=%s", value);
636 /* bash does not return an error when trying to export
637 * an undefined variable. Do likewise. */
643 perror_msg("export");
645 res = set_local_var(name, 1);
652 /* built-in 'fg' and 'bg' handler */
653 static int builtin_fg_bg(struct child_prog *child)
656 struct pipe *pi=NULL;
660 /* If they gave us no args, assume they want the last backgrounded task */
661 if (!child->argv[1]) {
662 for (pi = job_list; pi; pi = pi->next) {
663 if (pi->jobid == last_jobid) {
668 error_msg("%s: no current job", child->argv[0]);
672 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
673 error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
676 for (pi = job_list; pi; pi = pi->next) {
677 if (pi->jobid == jobnum) {
682 error_msg("%s: %d: no such job", child->argv[0], jobnum);
687 if (*child->argv[0] == 'f') {
688 /* Put the job into the foreground. */
689 tcsetpgrp(shell_terminal, pi->pgrp);
692 /* Restart the processes in the job */
693 for (i = 0; i < pi->num_progs; i++)
694 pi->progs[i].is_stopped = 0;
696 if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
700 perror_msg("kill (SIGCONT)");
704 pi->stopped_progs = 0;
708 /* built-in 'help' handler */
709 static int builtin_help(struct child_prog *dummy)
711 struct built_in_command *x;
713 printf("\nBuilt-in commands:\n");
714 printf("-------------------\n");
715 for (x = bltins; x->cmd; x++) {
718 printf("%s\t%s\n", x->cmd, x->descr);
724 /* built-in 'jobs' handler */
725 static int builtin_jobs(struct child_prog *child)
730 for (job = job_list; job; job = job->next) {
731 if (job->running_progs == job->stopped_progs)
732 status_string = "Stopped";
734 status_string = "Running";
736 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
742 /* built-in 'pwd' handler */
743 static int builtin_pwd(struct child_prog *dummy)
749 /* built-in 'read VAR' handler */
750 static int builtin_read(struct child_prog *child)
754 if (child->argv[1]) {
758 string[0] = 0; /* In case stdin has only EOF */
760 fgets(string, sizeof(string), stdin);
762 var = malloc(strlen(child->argv[1])+strlen(string)+2);
764 sprintf(var, "%s=%s", child->argv[1], string);
765 res = set_local_var(var, 0);
769 fprintf(stderr, "read: %m\n");
770 free(var); /* So not move up to avoid breaking errno */
773 do res=getchar(); while(res!='\n' && res!=EOF);
778 /* built-in 'set VAR=value' handler */
779 static int builtin_set(struct child_prog *child)
781 char *temp = child->argv[1];
785 for(e = top_vars; e; e=e->next)
786 printf("%s=%s\n", e->name, e->value);
788 set_local_var(temp, 0);
794 /* Built-in 'shift' handler */
795 static int builtin_shift(struct child_prog *child)
798 if (child->argv[1]) {
799 n=atoi(child->argv[1]);
801 if (n>=0 && n<global_argc) {
802 /* XXX This probably breaks $0 */
811 /* Built-in '.' handler (read-in and execute commands from file) */
812 static int builtin_source(struct child_prog *child)
817 if (child->argv[1] == NULL)
820 /* XXX search through $PATH is missing */
821 input = fopen(child->argv[1], "r");
823 error_msg("Couldn't open file '%s'", child->argv[1]);
827 /* Now run the file */
828 /* XXX argv and argc are broken; need to save old global_argv
829 * (pointer only is OK!) on this stack frame,
830 * set global_argv=child->argv+1, recurse, and restore. */
831 mark_open(fileno(input));
832 status = parse_file_outer(input);
833 mark_closed(fileno(input));
838 static int builtin_umask(struct child_prog *child)
841 const char *arg = child->argv[1];
844 new_umask=strtoul(arg, &end, 8);
845 if (*end!='\0' || end == arg) {
849 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
855 /* built-in 'unset VAR' handler */
856 static int builtin_unset(struct child_prog *child)
858 /* bash returned already true */
859 unset_local_var(child->argv[1]);
863 static int builtin_not_written(struct child_prog *child)
865 printf("builtin_%s not written\n",child->argv[0]);
870 static int b_check_space(o_string *o, int len)
872 /* It would be easy to drop a more restrictive policy
873 * in here, such as setting a maximum string length */
874 if (o->length + len > o->maxlen) {
875 char *old_data = o->data;
876 /* assert (data == NULL || o->maxlen != 0); */
877 o->maxlen += max(2*len, B_CHUNK);
878 o->data = realloc(o->data, 1 + o->maxlen);
879 if (o->data == NULL) {
883 return o->data == NULL;
886 static int b_addchr(o_string *o, int ch)
888 debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
889 if (b_check_space(o, 1)) return B_NOSPAC;
890 o->data[o->length] = ch;
892 o->data[o->length] = '\0';
896 static void b_reset(o_string *o)
900 if (o->data != NULL) *o->data = '\0';
903 static void b_free(o_string *o)
911 /* My analysis of quoting semantics tells me that state information
912 * is associated with a destination, not a source.
914 static int b_addqchr(o_string *o, int ch, int quote)
916 if (quote && strchr("*?[\\",ch)) {
918 rc = b_addchr(o, '\\');
921 return b_addchr(o, ch);
925 static int b_adduint(o_string *o, unsigned int i)
928 char *p = simple_itoa(i);
929 /* no escape checking necessary */
930 do r=b_addchr(o, *p++); while (r==0 && *p);
935 static int static_get(struct in_str *i)
938 if (ch=='\0') return EOF;
942 static int static_peek(struct in_str *i)
948 static inline void cmdedit_set_initial_prompt(void)
950 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
959 static inline void setup_prompt_string(int promptmode, char **prompt_str)
961 debug_printf("setup_prompt_string %d ",promptmode);
962 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
963 /* Set up the prompt */
964 if (promptmode == 1) {
966 PS1=xmalloc(strlen(cwd)+4);
967 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# ");
973 *prompt_str = (promptmode==1)? PS1 : PS2;
975 debug_printf("result %s\n",*prompt_str);
979 static void get_user_input(struct in_str *i)
983 static char the_command[BUFSIZ];
985 setup_prompt_string(i->promptmode, &prompt_str);
986 #ifdef CONFIG_FEATURE_COMMAND_EDITING
988 ** enable command line editing only while a command line
989 ** is actually being read; otherwise, we'll end up bequeathing
990 ** atexit() handlers and other unwanted stuff to our
991 ** child processes (rob@sysgo.de)
993 cmdedit_read_input(prompt_str, the_command);
995 fputs(prompt_str, stdout);
997 the_command[0]=fgetc(i->file);
1004 static char the_command[CONFIG_SYS_CBSIZE];
1006 #ifdef CONFIG_BOOT_RETRY_TIME
1007 # ifndef CONFIG_RESET_TO_RETRY
1008 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1010 reset_cmd_timeout();
1013 if (i->promptmode == 1) {
1014 n = readline(CONFIG_SYS_PROMPT);
1016 n = readline(CONFIG_SYS_PROMPT_HUSH_PS2);
1018 #ifdef CONFIG_BOOT_RETRY_TIME
1020 puts("\nTimeout waiting for command\n");
1021 # ifdef CONFIG_RESET_TO_RETRY
1022 do_reset(NULL, 0, 0, NULL);
1024 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1032 n = strlen(console_buffer);
1033 console_buffer[n] = '\n';
1034 console_buffer[n+1]= '\0';
1035 if (had_ctrlc()) flag_repeat = 0;
1038 if (i->promptmode == 1) {
1039 if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1040 strcpy(the_command,console_buffer);
1043 if (console_buffer[0] != '\n') {
1044 strcpy(the_command,console_buffer);
1054 if (console_buffer[0] != '\n') {
1055 if (strlen(the_command) + strlen(console_buffer)
1056 < CONFIG_SYS_CBSIZE) {
1057 n = strlen(the_command);
1058 the_command[n-1] = ' ';
1059 strcpy(&the_command[n],console_buffer);
1062 the_command[0] = '\n';
1063 the_command[1] = '\0';
1067 if (i->__promptme == 0) {
1068 the_command[0] = '\n';
1069 the_command[1] = '\0';
1071 i->p = console_buffer;
1076 /* This is the magic location that prints prompts
1077 * and gets data back from the user */
1078 static int file_get(struct in_str *i)
1083 /* If there is data waiting, eat it up */
1084 if (i->p && *i->p) {
1087 /* need to double check i->file because we might be doing something
1088 * more complicated by now, like sourcing or substituting. */
1090 if (i->__promptme && interactive && i->file == stdin) {
1091 while(! i->p || (interactive && strlen(i->p)==0) ) {
1093 while(! i->p || strlen(i->p)==0 ) {
1101 if (i->p && *i->p) {
1106 ch = fgetc(i->file);
1110 debug_printf("b_getch: got a %d\n", ch);
1113 if (ch == '\n') i->__promptme=1;
1118 /* All the callers guarantee this routine will never be
1119 * used right after a newline, so prompting is not needed.
1121 static int file_peek(struct in_str *i)
1124 if (i->p && *i->p) {
1129 i->peek_buf[0] = fgetc(i->file);
1130 i->peek_buf[1] = '\0';
1132 debug_printf("b_peek: got a %d\n", *i->p);
1139 static void setup_file_in_str(struct in_str *i, FILE *f)
1141 static void setup_file_in_str(struct in_str *i)
1144 i->peek = file_peek;
1154 static void setup_string_in_str(struct in_str *i, const char *s)
1156 i->peek = static_peek;
1157 i->get = static_get;
1164 static void mark_open(int fd)
1166 struct close_me *new = xmalloc(sizeof(struct close_me));
1168 new->next = close_me_head;
1169 close_me_head = new;
1172 static void mark_closed(int fd)
1174 struct close_me *tmp;
1175 if (close_me_head == NULL || close_me_head->fd != fd)
1176 error_msg_and_die("corrupt close_me");
1177 tmp = close_me_head;
1178 close_me_head = close_me_head->next;
1182 static void close_all(void)
1185 for (c=close_me_head; c; c=c->next) {
1188 close_me_head = NULL;
1191 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1192 * and stderr if they are redirected. */
1193 static int setup_redirects(struct child_prog *prog, int squirrel[])
1196 struct redir_struct *redir;
1198 for (redir=prog->redirects; redir; redir=redir->next) {
1199 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1200 /* something went wrong in the parse. Pretend it didn't happen */
1203 if (redir->dup == -1) {
1204 mode=redir_table[redir->type].mode;
1205 openfd = open(redir->word.gl_pathv[0], mode, 0666);
1207 /* this could get lost if stderr has been redirected, but
1208 bash and ash both lose it as well (though zsh doesn't!) */
1209 perror_msg("error opening %s", redir->word.gl_pathv[0]);
1213 openfd = redir->dup;
1216 if (openfd != redir->fd) {
1217 if (squirrel && redir->fd < 3) {
1218 squirrel[redir->fd] = dup(redir->fd);
1223 dup2(openfd, redir->fd);
1224 if (redir->dup == -1)
1232 static void restore_redirects(int squirrel[])
1235 for (i=0; i<3; i++) {
1238 /* No error checking. I sure wouldn't know what
1239 * to do with an error if I found one! */
1247 /* XXX no exit() here. If you don't exec, use _exit instead.
1248 * The at_exit handlers apparently confuse the calling process,
1249 * in particular stdin handling. Not sure why? */
1250 static void pseudo_exec(struct child_prog *child)
1254 struct built_in_command *x;
1256 for (i=0; is_assignment(child->argv[i]); i++) {
1257 debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1258 p = insert_var_value(child->argv[i]);
1260 if (p != child->argv[i]) free(p);
1262 child->argv+=i; /* XXX this hack isn't so horrible, since we are about
1263 to exit, and therefore don't need to keep data
1264 structures consistent for free() use. */
1265 /* If a variable is assigned in a forest, and nobody listens,
1266 * was it ever really set?
1268 if (child->argv[0] == NULL) {
1269 _exit(EXIT_SUCCESS);
1273 * Check if the command matches any of the builtins.
1274 * Depending on context, this might be redundant. But it's
1275 * easier to waste a few CPU cycles than it is to figure out
1276 * if this is one of those cases.
1278 for (x = bltins; x->cmd; x++) {
1279 if (strcmp(child->argv[0], x->cmd) == 0 ) {
1280 debug_printf("builtin exec %s\n", child->argv[0]);
1281 rcode = x->function(child);
1287 /* Check if the command matches any busybox internal commands
1289 * FIXME: This feature is not 100% safe, since
1290 * BusyBox is not fully reentrant, so we have no guarantee the things
1291 * from the .bss are still zeroed, or that things from .data are still
1292 * at their defaults. We could exec ourself from /proc/self/exe, but I
1293 * really dislike relying on /proc for things. We could exec ourself
1294 * from global_argv[0], but if we are in a chroot, we may not be able
1295 * to find ourself... */
1296 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1299 char** argv_l=child->argv;
1300 char *name = child->argv[0];
1302 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1303 /* Following discussions from November 2000 on the busybox mailing
1304 * list, the default configuration, (without
1305 * get_last_path_component()) lets the user force use of an
1306 * external command by specifying the full (with slashes) filename.
1307 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1308 * _aways_ override external commands, so if you want to run
1309 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1310 * filesystem and is _not_ busybox. Some systems may want this,
1312 name = get_last_path_component(name);
1314 /* Count argc for use in a second... */
1315 for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1317 debug_printf("running applet %s\n", name);
1318 run_applet_by_name(name, argc_l, child->argv);
1321 debug_printf("exec of %s\n",child->argv[0]);
1322 execvp(child->argv[0],child->argv);
1323 perror_msg("couldn't exec: %s",child->argv[0]);
1325 } else if (child->group) {
1326 debug_printf("runtime nesting to group\n");
1327 interactive=0; /* crucial!!!! */
1328 rcode = run_list_real(child->group);
1329 /* OK to leak memory by not calling free_pipe_list,
1330 * since this process is about to exit */
1333 /* Can happen. See what bash does with ">foo" by itself. */
1334 debug_printf("trying to pseudo_exec null command\n");
1335 _exit(EXIT_SUCCESS);
1339 static void insert_bg_job(struct pipe *pi)
1341 struct pipe *thejob;
1343 /* Linear search for the ID of the job to use */
1345 for (thejob = job_list; thejob; thejob = thejob->next)
1346 if (thejob->jobid >= pi->jobid)
1347 pi->jobid = thejob->jobid + 1;
1349 /* add thejob to the list of running jobs */
1351 thejob = job_list = xmalloc(sizeof(*thejob));
1353 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1354 thejob->next = xmalloc(sizeof(*thejob));
1355 thejob = thejob->next;
1358 /* physically copy the struct job */
1359 memcpy(thejob, pi, sizeof(struct pipe));
1360 thejob->next = NULL;
1361 thejob->running_progs = thejob->num_progs;
1362 thejob->stopped_progs = 0;
1363 thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1365 /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1367 char *bar=thejob->text;
1368 char **foo=pi->progs[0].argv;
1369 while(foo && *foo) {
1370 bar += sprintf(bar, "%s ", *foo++);
1374 /* we don't wait for background thejobs to return -- append it
1375 to the list of backgrounded thejobs and leave it alone */
1376 printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1377 last_bg_pid = thejob->progs[0].pid;
1378 last_jobid = thejob->jobid;
1381 /* remove a backgrounded job */
1382 static void remove_bg_job(struct pipe *pi)
1384 struct pipe *prev_pipe;
1386 if (pi == job_list) {
1387 job_list = pi->next;
1389 prev_pipe = job_list;
1390 while (prev_pipe->next != pi)
1391 prev_pipe = prev_pipe->next;
1392 prev_pipe->next = pi->next;
1395 last_jobid = job_list->jobid;
1399 pi->stopped_progs = 0;
1404 /* Checks to see if any processes have exited -- if they
1405 have, figure out why and see if a job has completed */
1406 static int checkjobs(struct pipe* fg_pipe)
1414 attributes = WUNTRACED;
1415 if (fg_pipe==NULL) {
1416 attributes |= WNOHANG;
1419 while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1422 for (i=0; i < fg_pipe->num_progs; i++) {
1423 if (fg_pipe->progs[i].pid == childpid) {
1424 if (i==fg_pipe->num_progs-1)
1425 rcode=WEXITSTATUS(status);
1426 (fg_pipe->num_progs)--;
1432 for (pi = job_list; pi; pi = pi->next) {
1434 while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1437 if (prognum < pi->num_progs)
1442 debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1446 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1448 pi->running_progs--;
1449 pi->progs[prognum].pid = 0;
1451 if (!pi->running_progs) {
1452 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1457 pi->stopped_progs++;
1458 pi->progs[prognum].is_stopped = 1;
1461 /* Printing this stuff is a pain, since it tends to
1462 * overwrite the prompt an inconveinient moments. So
1464 if (pi->stopped_progs == pi->num_progs) {
1465 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1471 if (childpid == -1 && errno != ECHILD)
1472 perror_msg("waitpid");
1474 /* move the shell to the foreground */
1475 /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1476 /* perror_msg("tcsetpgrp-2"); */
1480 /* Figure out our controlling tty, checking in order stderr,
1481 * stdin, and stdout. If check_pgrp is set, also check that
1482 * we belong to the foreground process group associated with
1483 * that tty. The value of shell_terminal is needed in order to call
1484 * tcsetpgrp(shell_terminal, ...); */
1485 void controlling_tty(int check_pgrp)
1489 if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1490 && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1491 && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1492 goto shell_terminal_error;
1494 if (check_pgrp && curpgrp != getpgid(0))
1495 goto shell_terminal_error;
1499 shell_terminal_error:
1500 shell_terminal = -1;
1505 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1506 * to finish. See checkjobs().
1508 * return code is normally -1, when the caller has to wait for children
1509 * to finish to determine the exit status of the pipe. If the pipe
1510 * is a simple builtin command, however, the action is done by the
1511 * time run_pipe_real returns, and the exit code is provided as the
1514 * The input of the pipe is always stdin, the output is always
1515 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1516 * because it tries to avoid running the command substitution in
1517 * subshell, when that is in fact necessary. The subshell process
1518 * now has its stdout directed to the input of the appropriate pipe,
1519 * so this routine is noticeably simpler.
1521 static int run_pipe_real(struct pipe *pi)
1525 int nextin, nextout;
1526 int pipefds[2]; /* pipefds[0] is for reading */
1527 struct child_prog *child;
1528 struct built_in_command *x;
1531 /* Avoid longjmp clobbering */
1539 int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1540 struct child_prog *child;
1544 /* Avoid longjmp clobbering */
1549 #endif /* __U_BOOT__ */
1556 /* Check if this is a simple builtin (not part of a pipe).
1557 * Builtins within pipes have to fork anyway, and are handled in
1558 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1560 if (pi->num_progs == 1) child = & (pi->progs[0]);
1562 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1563 int squirrel[] = {-1, -1, -1};
1565 debug_printf("non-subshell grouping\n");
1566 setup_redirects(child, squirrel);
1567 /* XXX could we merge code with following builtin case,
1568 * by creating a pseudo builtin that calls run_list_real? */
1569 rcode = run_list_real(child->group);
1570 restore_redirects(squirrel);
1572 if (pi->num_progs == 1 && child->group) {
1574 debug_printf("non-subshell grouping\n");
1575 rcode = run_list_real(child->group);
1578 } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1579 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1580 if (i!=0 && child->argv[i]==NULL) {
1581 /* assignments, but no command: set the local environment */
1582 for (i=0; child->argv[i]!=NULL; i++) {
1584 /* Ok, this case is tricky. We have to decide if this is a
1585 * local variable, or an already exported variable. If it is
1586 * already exported, we have to export the new value. If it is
1587 * not exported, we need only set this as a local variable.
1588 * This junk is all to decide whether or not to export this
1592 name = xstrdup(child->argv[i]);
1593 debug_printf("Local environment set: %s\n", name);
1594 value = strchr(name, '=');
1598 if ( get_local_var(name)) {
1603 p = insert_var_value(child->argv[i]);
1604 set_local_var(p, export_me);
1605 if (p != child->argv[i]) free(p);
1607 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1609 for (i = 0; is_assignment(child->argv[i]); i++) {
1610 p = insert_var_value(child->argv[i]);
1614 set_local_var(p, 0);
1616 if (p != child->argv[i]) {
1624 str = make_string((child->argv + i));
1625 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1627 return last_return_code;
1630 for (x = bltins; x->cmd; x++) {
1631 if (strcmp(child->argv[i], x->cmd) == 0 ) {
1632 int squirrel[] = {-1, -1, -1};
1634 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1635 debug_printf("magic exec\n");
1636 setup_redirects(child,NULL);
1637 return EXIT_SUCCESS;
1639 debug_printf("builtin inline %s\n", child->argv[0]);
1640 /* XXX setup_redirects acts on file descriptors, not FILEs.
1641 * This is perfect for work that comes after exec().
1642 * Is it really safe for inline use? Experimentally,
1643 * things seem to work with glibc. */
1644 setup_redirects(child, squirrel);
1646 child->argv += i; /* XXX horrible hack */
1647 rcode = x->function(child);
1648 /* XXX restore hack so free() can work right */
1650 restore_redirects(squirrel);
1655 /* check ";", because ,example , argv consist from
1656 * "help;flinfo" must not execute
1658 if (strchr(child->argv[i], ';')) {
1659 printf ("Unknown command '%s' - try 'help' or use 'run' command\n",
1663 /* Look up command in command table */
1666 if ((cmdtp = find_cmd(child->argv[i])) == NULL) {
1667 printf ("Unknown command '%s' - try 'help'\n", child->argv[i]);
1668 return -1; /* give up after bad command */
1671 #if defined(CONFIG_CMD_BOOTD)
1672 /* avoid "bootd" recursion */
1673 if (cmdtp->cmd == do_bootd) {
1674 if (flag & CMD_FLAG_BOOTD) {
1675 printf ("'bootd' recursion detected\n");
1679 flag |= CMD_FLAG_BOOTD;
1682 /* found - check max args */
1683 if ((child->argc - i) > cmdtp->maxargs)
1684 return cmd_usage(cmdtp);
1686 /* OK - call function to do the command */
1687 rcode = cmd_call(cmdtp, flag, child->argc,
1689 if (!cmdtp->repeatable)
1697 for (i = 0; i < pi->num_progs; i++) {
1698 child = & (pi->progs[i]);
1700 /* pipes are inserted between pairs of commands */
1701 if ((i + 1) < pi->num_progs) {
1702 if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1703 nextout = pipefds[1];
1709 /* XXX test for failed fork()? */
1710 if (!(child->pid = fork())) {
1711 /* Set the handling for job control signals back to the default. */
1712 signal(SIGINT, SIG_DFL);
1713 signal(SIGQUIT, SIG_DFL);
1714 signal(SIGTERM, SIG_DFL);
1715 signal(SIGTSTP, SIG_DFL);
1716 signal(SIGTTIN, SIG_DFL);
1717 signal(SIGTTOU, SIG_DFL);
1718 signal(SIGCHLD, SIG_DFL);
1730 if (pipefds[0]!=-1) {
1731 close(pipefds[0]); /* opposite end of our output pipe */
1734 /* Like bash, explicit redirects override pipes,
1735 * and the pipe fd is available for dup'ing. */
1736 setup_redirects(child,NULL);
1738 if (interactive && pi->followup!=PIPE_BG) {
1739 /* If we (the child) win the race, put ourselves in the process
1740 * group whose leader is the first process in this pipe. */
1742 pi->pgrp = getpid();
1744 if (setpgid(0, pi->pgrp) == 0) {
1745 tcsetpgrp(2, pi->pgrp);
1753 /* put our child in the process group whose leader is the
1754 first process in this pipe */
1756 pi->pgrp = child->pid;
1758 /* Don't check for errors. The child may be dead already,
1759 * in which case setpgid returns error code EACCES. */
1760 setpgid(child->pid, pi->pgrp);
1767 /* If there isn't another process, nextin is garbage
1768 but it doesn't matter */
1769 nextin = pipefds[0];
1775 static int run_list_real(struct pipe *pi)
1777 char *save_name = NULL;
1779 char **save_list = NULL;
1785 int rcode=0, flag_skip=1;
1786 int flag_restore = 0;
1787 int if_code=0, next_if_code=0; /* need double-buffer to handle elif */
1788 reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1789 /* check syntax for "for" */
1790 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1791 if ((rpipe->r_mode == RES_IN ||
1792 rpipe->r_mode == RES_FOR) &&
1793 (rpipe->next == NULL)) {
1800 if ((rpipe->r_mode == RES_IN &&
1801 (rpipe->next->r_mode == RES_IN &&
1802 rpipe->next->progs->argv != NULL))||
1803 (rpipe->r_mode == RES_FOR &&
1804 rpipe->next->r_mode != RES_IN)) {
1812 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1813 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1814 pi->r_mode == RES_FOR) {
1818 if ((had_ctrlc())) {
1829 debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n", rmode, if_code, next_if_code, skip_more_in_this_rmode);
1830 if (rmode == skip_more_in_this_rmode && flag_skip) {
1831 if (pi->followup == PIPE_SEQ) flag_skip=0;
1835 skip_more_in_this_rmode = RES_XXXX;
1836 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1837 if (rmode == RES_THEN && if_code) continue;
1838 if (rmode == RES_ELSE && !if_code) continue;
1839 if (rmode == RES_ELIF && !if_code) break;
1840 if (rmode == RES_FOR && pi->num_progs) {
1842 /* if no variable values after "in" we skip "for" */
1843 if (!pi->next->progs->argv) continue;
1844 /* create list of variable values */
1845 list = make_list_in(pi->next->progs->argv,
1846 pi->progs->argv[0]);
1848 save_name = pi->progs->argv[0];
1849 pi->progs->argv[0] = NULL;
1853 free(pi->progs->argv[0]);
1857 pi->progs->argv[0] = save_name;
1859 pi->progs->glob_result.gl_pathv[0] =
1864 /* insert new value from list for variable */
1865 if (pi->progs->argv[0])
1866 free(pi->progs->argv[0]);
1867 pi->progs->argv[0] = *list++;
1869 pi->progs->glob_result.gl_pathv[0] =
1874 if (rmode == RES_IN) continue;
1875 if (rmode == RES_DO) {
1876 if (!flag_rep) continue;
1878 if ((rmode == RES_DONE)) {
1885 if (pi->num_progs == 0) continue;
1887 save_num_progs = pi->num_progs; /* save number of programs */
1889 rcode = run_pipe_real(pi);
1890 debug_printf("run_pipe_real returned %d\n",rcode);
1893 /* We only ran a builtin: rcode was set by the return value
1894 * of run_pipe_real(), and we don't need to wait for anything. */
1895 } else if (pi->followup==PIPE_BG) {
1896 /* XXX check bash's behavior with nontrivial pipes */
1897 /* XXX compute jobid */
1898 /* XXX what does bash do with attempts to background builtins? */
1900 rcode = EXIT_SUCCESS;
1903 /* move the new process group into the foreground */
1904 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1905 perror_msg("tcsetpgrp-3");
1906 rcode = checkjobs(pi);
1907 /* move the shell to the foreground */
1908 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1909 perror_msg("tcsetpgrp-4");
1911 rcode = checkjobs(pi);
1913 debug_printf("checkjobs returned %d\n",rcode);
1915 last_return_code=rcode;
1918 last_return_code = -rcode - 2;
1919 return -2; /* exit */
1921 last_return_code=(rcode == 0) ? 0 : 1;
1924 pi->num_progs = save_num_progs; /* restore number of programs */
1926 if ( rmode == RES_IF || rmode == RES_ELIF )
1927 next_if_code=rcode; /* can be overwritten a number of times */
1928 if (rmode == RES_WHILE)
1929 flag_rep = !last_return_code;
1930 if (rmode == RES_UNTIL)
1931 flag_rep = last_return_code;
1932 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1933 (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1934 skip_more_in_this_rmode=rmode;
1942 /* broken, of course, but OK for testing */
1943 static char *indenter(int i)
1945 static char blanks[]=" ";
1946 return &blanks[sizeof(blanks)-i-1];
1949 /* return code is the exit status of the pipe */
1950 static int free_pipe(struct pipe *pi, int indent)
1953 struct child_prog *child;
1955 struct redir_struct *r, *rnext;
1957 int a, i, ret_code=0;
1958 char *ind = indenter(indent);
1961 if (pi->stopped_progs > 0)
1963 final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1965 for (i=0; i<pi->num_progs; i++) {
1966 child = &pi->progs[i];
1967 final_printf("%s command %d:\n",ind,i);
1969 for (a=0,p=child->argv; *p; a++,p++) {
1970 final_printf("%s argv[%d] = %s\n",ind,a,*p);
1973 globfree(&child->glob_result);
1975 for (a = 0; a < child->argc; a++) {
1976 free(child->argv[a]);
1982 } else if (child->group) {
1984 final_printf("%s begin group (subshell:%d)\n",ind, child->subshell);
1986 ret_code = free_pipe_list(child->group,indent+3);
1987 final_printf("%s end group\n",ind);
1989 final_printf("%s (nil)\n",ind);
1992 for (r=child->redirects; r; r=rnext) {
1993 final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1995 /* guard against the case >$FOO, where foo is unset or blank */
1996 if (r->word.gl_pathv) {
1997 final_printf(" %s\n", *r->word.gl_pathv);
2001 final_printf("&%d\n", r->dup);
2006 child->redirects=NULL;
2009 free(pi->progs); /* children are an array, they get freed all at once */
2014 static int free_pipe_list(struct pipe *head, int indent)
2016 int rcode=0; /* if list has no members */
2017 struct pipe *pi, *next;
2018 char *ind = indenter(indent);
2019 for (pi=head; pi; pi=next) {
2020 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
2021 rcode = free_pipe(pi, indent);
2022 final_printf("%s pipe followup code %d\n", ind, pi->followup);
2030 /* Select which version we will use */
2031 static int run_list(struct pipe *pi)
2037 rcode = run_list_real(pi);
2041 /* free_pipe_list has the side effect of clearing memory
2042 * In the long run that function can be merged with run_list_real,
2043 * but doing that now would hobble the debugging effort. */
2044 free_pipe_list(pi,0);
2048 /* The API for glob is arguably broken. This routine pushes a non-matching
2049 * string into the output structure, removing non-backslashed backslashes.
2050 * If someone can prove me wrong, by performing this function within the
2051 * original glob(3) api, feel free to rewrite this routine into oblivion.
2052 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2053 * XXX broken if the last character is '\\', check that before calling.
2056 static int globhack(const char *src, int flags, glob_t *pglob)
2061 for (cnt=1, s=src; s && *s; s++) {
2062 if (*s == '\\') s++;
2066 if (!dest) return GLOB_NOSPACE;
2067 if (!(flags & GLOB_APPEND)) {
2068 pglob->gl_pathv=NULL;
2073 pathc = ++pglob->gl_pathc;
2074 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2075 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2076 pglob->gl_pathv[pathc-1]=dest;
2077 pglob->gl_pathv[pathc]=NULL;
2078 for (s=src; s && *s; s++, dest++) {
2079 if (*s == '\\') s++;
2086 /* XXX broken if the last character is '\\', check that before calling */
2087 static int glob_needed(const char *s)
2090 if (*s == '\\') s++;
2091 if (strchr("*[?",*s)) return 1;
2097 static void globprint(glob_t *pglob)
2100 debug_printf("glob_t at %p:\n", pglob);
2101 debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
2102 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2103 for (i=0; i<pglob->gl_pathc; i++)
2104 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2105 pglob->gl_pathv[i], pglob->gl_pathv[i]);
2109 static int xglob(o_string *dest, int flags, glob_t *pglob)
2113 /* short-circuit for null word */
2114 /* we can code this better when the debug_printf's are gone */
2115 if (dest->length == 0) {
2116 if (dest->nonnull) {
2117 /* bash man page calls this an "explicit" null */
2118 gr = globhack(dest->data, flags, pglob);
2119 debug_printf("globhack returned %d\n",gr);
2123 } else if (glob_needed(dest->data)) {
2124 gr = glob(dest->data, flags, NULL, pglob);
2125 debug_printf("glob returned %d\n",gr);
2126 if (gr == GLOB_NOMATCH) {
2127 /* quote removal, or more accurately, backslash removal */
2128 gr = globhack(dest->data, flags, pglob);
2129 debug_printf("globhack returned %d\n",gr);
2132 gr = globhack(dest->data, flags, pglob);
2133 debug_printf("globhack returned %d\n",gr);
2135 if (gr == GLOB_NOSPACE)
2136 error_msg_and_die("out of memory during glob");
2137 if (gr != 0) { /* GLOB_ABORTED ? */
2138 error_msg("glob(3) error %d",gr);
2140 /* globprint(glob_target); */
2146 static char *get_dollar_var(char ch);
2149 /* This is used to get/check local shell variables */
2150 char *get_local_var(const char *s)
2152 struct variables *cur;
2159 return get_dollar_var(s[1]);
2162 for (cur = top_vars; cur; cur=cur->next)
2163 if(strcmp(cur->name, s)==0)
2168 /* This is used to set local shell variables
2169 flg_export==0 if only local (not exporting) variable
2170 flg_export==1 if "new" exporting environ
2171 flg_export>1 if current startup environ (not call putenv()) */
2172 int set_local_var(const char *s, int flg_export)
2176 struct variables *cur;
2179 /* might be possible! */
2187 if (getenv(name) != NULL) {
2189 "There is a global environment variable with the same name.\n");
2194 /* Assume when we enter this function that we are already in
2195 * NAME=VALUE format. So the first order of business is to
2196 * split 's' on the '=' into 'name' and 'value' */
2197 value = strchr(name, '=');
2198 if (value==0 && ++value==0) {
2204 for(cur = top_vars; cur; cur = cur->next) {
2205 if(strcmp(cur->name, name)==0)
2210 if(strcmp(cur->value, value)==0) {
2211 if(flg_export>0 && cur->flg_export==0)
2212 cur->flg_export=flg_export;
2216 if(cur->flg_read_only) {
2217 error_msg("%s: readonly variable", name);
2220 if(flg_export>0 || cur->flg_export>1)
2224 cur->value = strdup(value);
2228 cur = malloc(sizeof(struct variables));
2232 cur->name = strdup(name);
2233 if(cur->name == 0) {
2237 struct variables *bottom = top_vars;
2238 cur->value = strdup(value);
2240 cur->flg_export = flg_export;
2241 cur->flg_read_only = 0;
2242 while(bottom->next) bottom=bottom->next;
2249 if(result==0 && cur->flg_export==1) {
2251 result = putenv(name);
2256 if(result>0) /* equivalent to previous set */
2263 void unset_local_var(const char *name)
2265 struct variables *cur;
2268 for (cur = top_vars; cur; cur=cur->next) {
2269 if(strcmp(cur->name, name)==0)
2273 struct variables *next = top_vars;
2274 if(cur->flg_read_only) {
2275 error_msg("%s: readonly variable", name);
2280 unsetenv(cur->name);
2284 while (next->next != cur)
2286 next->next = cur->next;
2293 static int is_assignment(const char *s)
2298 if (!isalpha(*s)) return 0;
2300 while(isalnum(*s) || *s=='_') ++s;
2305 /* the src parameter allows us to peek forward to a possible &n syntax
2306 * for file descriptor duplication, e.g., "2>&1".
2307 * Return code is 0 normally, 1 if a syntax error is detected in src.
2308 * Resource errors (in xmalloc) cause the process to exit */
2309 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2310 struct in_str *input)
2312 struct child_prog *child=ctx->child;
2313 struct redir_struct *redir = child->redirects;
2314 struct redir_struct *last_redir=NULL;
2316 /* Create a new redir_struct and drop it onto the end of the linked list */
2321 redir = xmalloc(sizeof(struct redir_struct));
2323 redir->word.gl_pathv=NULL;
2325 last_redir->next=redir;
2327 child->redirects=redir;
2331 redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2333 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2335 /* Check for a '2>&1' type redirect */
2336 redir->dup = redirect_dup_num(input);
2337 if (redir->dup == -2) return 1; /* syntax error */
2338 if (redir->dup != -1) {
2339 /* Erik had a check here that the file descriptor in question
2340 * is legit; I postpone that to "run time"
2341 * A "-" representation of "close me" shows up as a -3 here */
2342 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2344 /* We do _not_ try to open the file that src points to,
2345 * since we need to return and let src be expanded first.
2346 * Set ctx->pending_redirect, so we know what to do at the
2347 * end of the next parsed word.
2349 ctx->pending_redirect = redir;
2355 struct pipe *new_pipe(void) {
2357 pi = xmalloc(sizeof(struct pipe));
2361 pi->followup = 0; /* invalid */
2362 pi->r_mode = RES_NONE;
2366 static void initialize_context(struct p_context *ctx)
2370 ctx->pending_redirect=NULL;
2373 ctx->list_head=new_pipe();
2374 ctx->pipe=ctx->list_head;
2380 done_command(ctx); /* creates the memory for working child */
2383 /* normal return is 0
2384 * if a reserved word is found, and processed, return 1
2385 * should handle if, then, elif, else, fi, for, while, until, do, done.
2386 * case, function, and select are obnoxious, save those for later.
2388 struct reserved_combo {
2393 /* Mostly a list of accepted follow-up reserved words.
2394 * FLAG_END means we are done with the sequence, and are ready
2395 * to turn the compound list into a command.
2396 * FLAG_START means the word must start a new compound list.
2398 static struct reserved_combo reserved_list[] = {
2399 { "if", RES_IF, FLAG_THEN | FLAG_START },
2400 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2401 { "elif", RES_ELIF, FLAG_THEN },
2402 { "else", RES_ELSE, FLAG_FI },
2403 { "fi", RES_FI, FLAG_END },
2404 { "for", RES_FOR, FLAG_IN | FLAG_START },
2405 { "while", RES_WHILE, FLAG_DO | FLAG_START },
2406 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
2407 { "in", RES_IN, FLAG_DO },
2408 { "do", RES_DO, FLAG_DONE },
2409 { "done", RES_DONE, FLAG_END }
2411 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2413 int reserved_word(o_string *dest, struct p_context *ctx)
2415 struct reserved_combo *r;
2416 for (r=reserved_list;
2417 r<reserved_list+NRES; r++) {
2418 if (strcmp(dest->data, r->literal) == 0) {
2419 debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2420 if (r->flag & FLAG_START) {
2421 struct p_context *new = xmalloc(sizeof(struct p_context));
2422 debug_printf("push stack\n");
2423 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2430 *new = *ctx; /* physical copy */
2431 initialize_context(ctx);
2433 } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2440 ctx->old_flag = r->flag;
2441 if (ctx->old_flag & FLAG_END) {
2442 struct p_context *old;
2443 debug_printf("pop stack\n");
2444 done_pipe(ctx,PIPE_SEQ);
2446 old->child->group = ctx->list_head;
2448 old->child->subshell = 0;
2450 *ctx = *old; /* physical copy */
2460 /* normal return is 0.
2461 * Syntax or xglob errors return 1. */
2462 static int done_word(o_string *dest, struct p_context *ctx)
2464 struct child_prog *child=ctx->child;
2466 glob_t *glob_target;
2473 debug_printf("done_word: %s %p\n", dest->data, child);
2474 if (dest->length == 0 && !dest->nonnull) {
2475 debug_printf(" true null, ignored\n");
2479 if (ctx->pending_redirect) {
2480 glob_target = &ctx->pending_redirect->word;
2485 return 1; /* syntax error, groups and arglists don't mix */
2487 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2488 debug_printf("checking %s for reserved-ness\n",dest->data);
2489 if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2492 glob_target = &child->glob_result;
2493 if (child->argv) flags |= GLOB_APPEND;
2495 for (cnt = 1, s = dest->data; s && *s; s++) {
2496 if (*s == '\\') s++;
2501 if ( child->argv == NULL) {
2504 argc = ++child->argc;
2505 child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2506 if (child->argv == NULL) return 1;
2507 child->argv[argc-1]=str;
2508 child->argv[argc]=NULL;
2509 for (s = dest->data; s && *s; s++,str++) {
2510 if (*s == '\\') s++;
2517 gr = xglob(dest, flags, glob_target);
2518 if (gr != 0) return 1;
2523 if (ctx->pending_redirect) {
2524 ctx->pending_redirect=NULL;
2525 if (glob_target->gl_pathc != 1) {
2526 error_msg("ambiguous redirect");
2530 child->argv = glob_target->gl_pathv;
2533 if (ctx->w == RES_FOR) {
2534 done_word(dest,ctx);
2535 done_pipe(ctx,PIPE_SEQ);
2540 /* The only possible error here is out of memory, in which case
2542 static int done_command(struct p_context *ctx)
2544 /* The child is really already in the pipe structure, so
2545 * advance the pipe counter and make a new, null child.
2546 * Only real trickiness here is that the uncommitted
2547 * child structure, to which ctx->child points, is not
2548 * counted in pi->num_progs. */
2549 struct pipe *pi=ctx->pipe;
2550 struct child_prog *prog=ctx->child;
2552 if (prog && prog->group == NULL
2553 && prog->argv == NULL
2555 && prog->redirects == NULL) {
2559 debug_printf("done_command: skipping null command\n");
2563 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2565 debug_printf("done_command: initializing\n");
2567 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2569 prog = pi->progs + pi->num_progs;
2571 prog->redirects = NULL;
2575 prog->is_stopped = 0;
2579 prog->glob_result.gl_pathv = NULL;
2584 prog->type = ctx->type;
2586 /* but ctx->pipe and ctx->list_head remain unchanged */
2590 static int done_pipe(struct p_context *ctx, pipe_style type)
2593 done_command(ctx); /* implicit closure of previous command */
2594 debug_printf("done_pipe, type %d\n", type);
2595 ctx->pipe->followup = type;
2596 ctx->pipe->r_mode = ctx->w;
2598 ctx->pipe->next = new_p;
2601 done_command(ctx); /* set up new pipe to accept commands */
2606 /* peek ahead in the in_str to find out if we have a "&n" construct,
2607 * as in "2>&1", that represents duplicating a file descriptor.
2608 * returns either -2 (syntax error), -1 (no &), or the number found.
2610 static int redirect_dup_num(struct in_str *input)
2614 if (ch != '&') return -1;
2616 b_getch(input); /* get the & */
2620 return -3; /* "-" represents "close me" */
2622 while (isdigit(ch)) {
2630 error_msg("ambiguous redirect");
2634 /* If a redirect is immediately preceded by a number, that number is
2635 * supposed to tell which file descriptor to redirect. This routine
2636 * looks for such preceding numbers. In an ideal world this routine
2637 * needs to handle all the following classes of redirects...
2638 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2639 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2640 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2641 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2642 * A -1 output from this program means no valid number was found, so the
2643 * caller should use the appropriate default for this redirection.
2645 static int redirect_opt_num(o_string *o)
2649 if (o->length==0) return -1;
2650 for(num=0; num<o->length; num++) {
2651 if (!isdigit(*(o->data+num))) {
2655 /* reuse num (and save an int) */
2661 FILE *generate_stream_from_list(struct pipe *head)
2665 int pid, channel[2];
2666 if (pipe(channel)<0) perror_msg_and_die("pipe");
2669 perror_msg_and_die("fork");
2670 } else if (pid==0) {
2672 if (channel[1] != 1) {
2677 #define SURROGATE "surrogate response"
2678 write(1,SURROGATE,sizeof(SURROGATE));
2679 _exit(run_list(head));
2681 _exit(run_list_real(head)); /* leaks memory */
2684 debug_printf("forked child %d\n",pid);
2686 pf = fdopen(channel[0],"r");
2687 debug_printf("pipe on FILE *%p\n",pf);
2689 free_pipe_list(head,0);
2690 pf=popen("echo surrogate response","r");
2691 debug_printf("started fake pipe on FILE *%p\n",pf);
2696 /* this version hacked for testing purposes */
2697 /* return code is exit status of the process that is run. */
2698 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2701 o_string result=NULL_O_STRING;
2702 struct p_context inner;
2704 struct in_str pipe_str;
2705 initialize_context(&inner);
2707 /* recursion to generate command */
2708 retcode = parse_stream(&result, &inner, input, subst_end);
2709 if (retcode != 0) return retcode; /* syntax error or EOF */
2710 done_word(&result, &inner);
2711 done_pipe(&inner, PIPE_SEQ);
2714 p=generate_stream_from_list(inner.list_head);
2715 if (p==NULL) return 1;
2716 mark_open(fileno(p));
2717 setup_file_in_str(&pipe_str, p);
2719 /* now send results of command back into original context */
2720 retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2721 /* XXX In case of a syntax error, should we try to kill the child?
2722 * That would be tough to do right, so just read until EOF. */
2724 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2727 debug_printf("done reading from pipe, pclose()ing\n");
2728 /* This is the step that wait()s for the child. Should be pretty
2729 * safe, since we just read an EOF from its stdout. We could try
2730 * to better, by using wait(), and keeping track of background jobs
2731 * at the same time. That would be a lot of work, and contrary
2732 * to the KISS philosophy of this program. */
2733 mark_closed(fileno(p));
2735 free_pipe_list(inner.list_head,0);
2736 debug_printf("pclosed, retcode=%d\n",retcode);
2737 /* XXX this process fails to trim a single trailing newline */
2741 static int parse_group(o_string *dest, struct p_context *ctx,
2742 struct in_str *input, int ch)
2745 struct p_context sub;
2746 struct child_prog *child = ctx->child;
2749 return 1; /* syntax error, groups and arglists don't mix */
2751 initialize_context(&sub);
2753 case '(': endch=')'; child->subshell=1; break;
2754 case '{': endch='}'; break;
2755 default: syntax(); /* really logic error */
2757 rcode=parse_stream(dest,&sub,input,endch);
2758 done_word(dest,&sub); /* finish off the final word in the subcontext */
2759 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2760 child->group = sub.list_head;
2762 /* child remains "open", available for possible redirects */
2766 /* basically useful version until someone wants to get fancier,
2767 * see the bash man page under "Parameter Expansion" */
2768 static char *lookup_param(char *src)
2777 p = get_local_var(src);
2783 static char *get_dollar_var(char ch)
2785 static char buf[40];
2790 sprintf(buf, "%u", (unsigned int)last_return_code);
2799 /* return code: 0 for OK, 1 for syntax error */
2800 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2810 int ch = input->peek(input); /* first character after the $ */
2811 debug_printf("handle_dollar: ch=%c\n",ch);
2813 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2815 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2819 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2821 } else if (isdigit(ch)) {
2822 i = ch-'0'; /* XXX is $0 special? */
2823 if (i<global_argc) {
2824 parse_string(dest, ctx, global_argv[i]); /* recursion */
2828 } else switch (ch) {
2831 b_adduint(dest,getpid());
2835 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2841 b_adduint(dest,last_return_code);
2844 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2845 b_addchr(dest, '$');
2846 b_addchr(dest, '?');
2847 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2853 b_adduint(dest,global_argc ? global_argc-1 : 0);
2858 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2861 /* XXX maybe someone will try to escape the '}' */
2862 while(ch=b_getch(input),ch!=EOF && ch!='}') {
2869 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2874 process_command_subs(dest, ctx, input, ')');
2878 for (i=1; i<global_argc; i++) {
2879 parse_string(dest, ctx, global_argv[i]);
2880 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2886 /* still unhandled, but should be eventually */
2887 error_msg("unhandled syntax: $%c",ch);
2892 b_addqchr(dest,'$',dest->quote);
2894 /* Eat the character if the flag was set. If the compiler
2895 * is smart enough, we could substitute "b_getch(input);"
2896 * for all the "advance = 1;" above, and also end up with
2897 * a nice size-optimized program. Hah! That'll be the day.
2899 if (advance) b_getch(input);
2904 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2907 setup_string_in_str(&foo, src);
2908 return parse_stream(dest, ctx, &foo, '\0');
2912 /* return code is 0 for normal exit, 1 for syntax error */
2913 int parse_stream(o_string *dest, struct p_context *ctx,
2914 struct in_str *input, int end_trigger)
2919 redir_type redir_style;
2923 /* Only double-quote state is handled in the state variable dest->quote.
2924 * A single-quote triggers a bypass of the main loop until its mate is
2925 * found. When recursing, quote state is passed in via dest->quote. */
2927 debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2928 while ((ch=b_getch(input))!=EOF) {
2931 if (input->__promptme == 0) return 1;
2933 next = (ch == '\n') ? 0 : b_peek(input);
2935 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2936 ch >= ' ' ? ch : '.', ch, m,
2937 dest->quote, ctx->stack == NULL ? '*' : '.');
2939 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2940 b_addqchr(dest, ch, dest->quote);
2942 if (m==2) { /* unquoted IFS */
2943 if (done_word(dest, ctx)) {
2946 /* If we aren't performing a substitution, treat a newline as a
2947 * command separator. */
2948 if (end_trigger != '\0' && ch=='\n')
2949 done_pipe(ctx,PIPE_SEQ);
2951 if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2952 debug_printf("leaving parse_stream (triggered)\n");
2957 /* Yahoo! Time to run with it! */
2958 done_pipe(ctx,PIPE_SEQ);
2959 run_list(ctx->list_head);
2960 initialize_context(ctx);
2963 if (m!=2) switch (ch) {
2965 if (dest->length == 0 && !dest->quote) {
2966 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2968 b_addqchr(dest, ch, dest->quote);
2976 b_addqchr(dest, '\\', dest->quote);
2977 b_addqchr(dest, b_getch(input), dest->quote);
2980 if (handle_dollar(dest, ctx, input)!=0) return 1;
2984 while(ch=b_getch(input),ch!=EOF && ch!='\'') {
2986 if(input->__promptme == 0) return 1;
2997 dest->quote = !dest->quote;
3001 process_command_subs(dest, ctx, input, '`');
3004 redir_fd = redirect_opt_num(dest);
3005 done_word(dest, ctx);
3006 redir_style=REDIRECT_OVERWRITE;
3008 redir_style=REDIRECT_APPEND;
3010 } else if (next == '(') {
3011 syntax(); /* until we support >(list) Process Substitution */
3014 setup_redirect(ctx, redir_fd, redir_style, input);
3017 redir_fd = redirect_opt_num(dest);
3018 done_word(dest, ctx);
3019 redir_style=REDIRECT_INPUT;
3021 redir_style=REDIRECT_HEREIS;
3023 } else if (next == '>') {
3024 redir_style=REDIRECT_IO;
3026 } else if (next == '(') {
3027 syntax(); /* until we support <(list) Process Substitution */
3030 setup_redirect(ctx, redir_fd, redir_style, input);
3034 done_word(dest, ctx);
3035 done_pipe(ctx,PIPE_SEQ);
3038 done_word(dest, ctx);
3041 done_pipe(ctx,PIPE_AND);
3044 done_pipe(ctx,PIPE_BG);
3052 done_word(dest, ctx);
3055 done_pipe(ctx,PIPE_OR);
3057 /* we could pick up a file descriptor choice here
3058 * with redirect_opt_num(), but bash doesn't do it.
3059 * "echo foo 2| cat" yields "foo 2". */
3071 if (parse_group(dest, ctx, input, ch)!=0) return 1;
3075 syntax(); /* Proper use of this character caught by end_trigger */
3080 syntax(); /* this is really an internal logic error */
3085 /* complain if quote? No, maybe we just finished a command substitution
3086 * that was quoted. Example:
3087 * $ echo "`cat foo` plus more"
3088 * and we just got the EOF generated by the subshell that ran "cat foo"
3089 * The only real complaint is if we got an EOF when end_trigger != '\0',
3090 * that is, we were really supposed to get end_trigger, and never got
3091 * one before the EOF. Can't use the standard "syntax error" return code,
3092 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3093 debug_printf("leaving parse_stream (EOF)\n");
3094 if (end_trigger != '\0') return -1;
3098 void mapset(const unsigned char *set, int code)
3100 const unsigned char *s;
3101 for (s=set; *s; s++) map[*s] = code;
3104 void update_ifs_map(void)
3106 /* char *ifs and char map[256] are both globals. */
3107 ifs = (uchar *)getenv("IFS");
3108 if (ifs == NULL) ifs=(uchar *)" \t\n";
3109 /* Precompute a list of 'flow through' behavior so it can be treated
3110 * quickly up front. Computation is necessary because of IFS.
3111 * Special case handling of IFS == " \t\n" is not implemented.
3112 * The map[] array only really needs two bits each, and on most machines
3113 * that would be faster because of the reduced L1 cache footprint.
3115 memset(map,0,sizeof(map)); /* most characters flow through always */
3117 mapset((uchar *)"\\$'\"`", 3); /* never flow through */
3118 mapset((uchar *)"<>;&|(){}#", 1); /* flow through if quoted */
3120 mapset((uchar *)"\\$'\"", 3); /* never flow through */
3121 mapset((uchar *)";&|#", 1); /* flow through if quoted */
3123 mapset(ifs, 2); /* also flow through if quoted */
3126 /* most recursion does not come through here, the exeception is
3127 * from builtin_source() */
3128 int parse_stream_outer(struct in_str *inp, int flag)
3131 struct p_context ctx;
3132 o_string temp=NULL_O_STRING;
3139 initialize_context(&ctx);
3141 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3143 rcode = parse_stream(&temp, &ctx, inp, '\n');
3145 if (rcode == 1) flag_repeat = 0;
3147 if (rcode != 1 && ctx.old_flag != 0) {
3153 if (rcode != 1 && ctx.old_flag == 0) {
3154 done_word(&temp, &ctx);
3155 done_pipe(&ctx,PIPE_SEQ);
3157 run_list(ctx.list_head);
3159 code = run_list(ctx.list_head);
3160 if (code == -2) { /* exit */
3163 /* XXX hackish way to not allow exit from main loop */
3164 if (inp->peek == file_peek) {
3165 printf("exit not allowed from main input shell.\n");
3174 if (ctx.old_flag != 0) {
3179 if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3180 inp->__promptme = 1;
3185 free_pipe_list(ctx.list_head,0);
3188 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
3192 return (code != 0) ? 1 : 0;
3193 #endif /* __U_BOOT__ */
3197 static int parse_string_outer(const char *s, int flag)
3199 int parse_string_outer(const char *s, int flag)
3200 #endif /* __U_BOOT__ */
3202 struct in_str input;
3208 if (!(p = strchr(s, '\n')) || *++p) {
3209 p = xmalloc(strlen(s) + 2);
3212 setup_string_in_str(&input, p);
3213 rcode = parse_stream_outer(&input, flag);
3218 setup_string_in_str(&input, s);
3219 return parse_stream_outer(&input, flag);
3226 static int parse_file_outer(FILE *f)
3228 int parse_file_outer(void)
3232 struct in_str input;
3234 setup_file_in_str(&input, f);
3236 setup_file_in_str(&input);
3238 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3243 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3244 static void u_boot_hush_reloc(void)
3247 struct reserved_combo *r;
3249 for (r=reserved_list; r<reserved_list+NRES; r++) {
3250 addr = (ulong) (r->literal) + gd->reloc_off;
3251 r->literal = (char *)addr;
3256 int u_boot_hush_start(void)
3258 if (top_vars == NULL) {
3259 top_vars = malloc(sizeof(struct variables));
3260 top_vars->name = "HUSH_VERSION";
3261 top_vars->value = "0.01";
3263 top_vars->flg_export = 0;
3264 top_vars->flg_read_only = 1;
3265 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3266 u_boot_hush_reloc();
3272 static void *xmalloc(size_t size)
3276 if (!(p = malloc(size))) {
3277 printf("ERROR : memory not allocated\n");
3283 static void *xrealloc(void *ptr, size_t size)
3287 if (!(p = realloc(ptr, size))) {
3288 printf("ERROR : memory not allocated\n");
3293 #endif /* __U_BOOT__ */
3296 /* Make sure we have a controlling tty. If we get started under a job
3297 * aware app (like bash for example), make sure we are now in charge so
3298 * we don't fight over who gets the foreground */
3299 static void setup_job_control(void)
3301 static pid_t shell_pgrp;
3302 /* Loop until we are in the foreground. */
3303 while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3304 kill (- shell_pgrp, SIGTTIN);
3306 /* Ignore interactive and job-control signals. */
3307 signal(SIGINT, SIG_IGN);
3308 signal(SIGQUIT, SIG_IGN);
3309 signal(SIGTERM, SIG_IGN);
3310 signal(SIGTSTP, SIG_IGN);
3311 signal(SIGTTIN, SIG_IGN);
3312 signal(SIGTTOU, SIG_IGN);
3313 signal(SIGCHLD, SIG_IGN);
3315 /* Put ourselves in our own process group. */
3317 shell_pgrp = getpid ();
3318 setpgid (shell_pgrp, shell_pgrp);
3320 /* Grab control of the terminal. */
3321 tcsetpgrp(shell_terminal, shell_pgrp);
3324 int hush_main(int argc, char * const *argv)
3330 /* XXX what should these be while sourcing /etc/profile? */
3334 /* (re?) initialize globals. Sometimes hush_main() ends up calling
3335 * hush_main(), therefore we cannot rely on the BSS to zero out this
3336 * stuff. Reset these to 0 every time. */
3338 /* map[] is taken care of with call to update_ifs_map() */
3341 close_me_head = NULL;
3346 /* Initialize some more globals to non-zero values */
3348 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3349 cmdedit_set_initial_prompt();
3355 /* initialize our shell local variables with the values
3356 * currently living in the environment */
3359 set_local_var(*e, 2); /* without call putenv() */
3362 last_return_code=EXIT_SUCCESS;
3365 if (argv[0] && argv[0][0] == '-') {
3366 debug_printf("\nsourcing /etc/profile\n");
3367 if ((input = fopen("/etc/profile", "r")) != NULL) {
3368 mark_open(fileno(input));
3369 parse_file_outer(input);
3370 mark_closed(fileno(input));
3376 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3380 global_argv = argv+optind;
3381 global_argc = argc-optind;
3382 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3394 fprintf(stderr, "Usage: sh [FILE]...\n"
3395 " or: sh -c command [args]...\n\n");
3402 /* A shell is interactive if the `-i' flag was given, or if all of
3403 * the following conditions are met:
3405 * no arguments remaining or the -s flag given
3406 * standard input is a terminal
3407 * standard output is a terminal
3408 * Refer to Posix.2, the description of the `sh' utility. */
3409 if (argv[optind]==NULL && input==stdin &&
3410 isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3414 debug_printf("\ninteractive=%d\n", interactive);
3416 /* Looks like they want an interactive shell */
3417 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3418 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3419 printf( "Enter 'help' for a list of built-in commands.\n\n");
3421 setup_job_control();
3424 if (argv[optind]==NULL) {
3425 opt=parse_file_outer(stdin);
3429 debug_printf("\nrunning script '%s'\n", argv[optind]);
3430 global_argv = argv+optind;
3431 global_argc = argc-optind;
3432 input = xfopen(argv[optind], "r");
3433 opt = parse_file_outer(input);
3435 #ifdef CONFIG_FEATURE_CLEAN_UP
3437 if (cwd && cwd != unknown)
3440 struct variables *cur, *tmp;
3441 for(cur = top_vars; cur; cur = tmp) {
3443 if (!cur->flg_read_only) {
3453 return(opt?opt:last_return_code);
3457 static char *insert_var_value(char *inp)
3459 int res_str_len = 0;
3462 char *p, *p1, *res_str = NULL;
3464 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3467 res_str = xrealloc(res_str, (res_str_len + len));
3468 strncpy((res_str + res_str_len), inp, len);
3472 p = strchr(inp, SPECIAL_VAR_SYMBOL);
3474 if ((p1 = lookup_param(inp))) {
3475 len = res_str_len + strlen(p1);
3476 res_str = xrealloc(res_str, (1 + len));
3477 strcpy((res_str + res_str_len), p1);
3480 *p = SPECIAL_VAR_SYMBOL;
3485 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3486 strcpy((res_str + res_str_len), inp);
3487 while ((p = strchr(res_str, '\n'))) {
3491 return (res_str == NULL) ? inp : res_str;
3494 static char **make_list_in(char **inp, char *name)
3497 int name_len = strlen(name);
3502 /* create list of variable values */
3503 list = xmalloc(sizeof(*list));
3504 for (i = 0; inp[i]; i++) {
3505 p3 = insert_var_value(inp[i]);
3512 if ((p2 = strchr(p1, ' '))) {
3518 /* we use n + 2 in realloc for list,because we add
3519 * new element and then we will add NULL element */
3520 list = xrealloc(list, sizeof(*list) * (n + 2));
3521 list[n] = xmalloc(2 + name_len + len);
3522 strcpy(list[n], name);
3523 strcat(list[n], "=");
3524 strncat(list[n], p1, len);
3525 list[n++][name_len + len + 1] = '\0';
3528 if (p3 != inp[i]) free(p3);
3534 /* Make new string for parser */
3535 static char * make_string(char ** inp)
3542 for (n = 0; inp[n]; n++) {
3543 p = insert_var_value(inp[n]);
3544 str = xrealloc(str, (len + strlen(p)));
3551 len = strlen(str) + 3;
3552 if (p != inp[n]) free(p);
3555 *(str + len) = '\n';
3556 *(str + len + 1) = '\0';
3561 int do_showvar (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
3565 struct variables *cur;
3567 if (argc == 1) { /* Print all env variables */
3568 for (cur = top_vars; cur; cur = cur->next) {
3569 printf ("%s=%s\n", cur->name, cur->value);
3571 puts ("\n ** Abort\n");
3577 for (i = 1; i < argc; ++i) { /* print single env variables */
3578 char *name = argv[i];
3581 for (cur = top_vars; cur; cur = cur->next) {
3582 if(strcmp (cur->name, name) == 0) {
3584 printf ("%s=%s\n", cur->name, cur->value);
3587 puts ("\n ** Abort\n");
3592 printf ("## Error: \"%s\" not defined\n", name);
3600 showvar, CONFIG_SYS_MAXARGS, 1, do_showvar,
3601 "print local hushshell variables",
3602 "\n - print values of all hushshell variables\n"
3603 "showvar name ...\n"
3604 " - print value of hushshell variable 'name'"
3608 /****************************************************************************/