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);
1003 extern char console_buffer[];
1005 static char the_command[CONFIG_SYS_CBSIZE];
1007 #ifdef CONFIG_BOOT_RETRY_TIME
1008 # ifndef CONFIG_RESET_TO_RETRY
1009 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1011 reset_cmd_timeout();
1014 if (i->promptmode == 1) {
1015 n = readline(CONFIG_SYS_PROMPT);
1017 n = readline(CONFIG_SYS_PROMPT_HUSH_PS2);
1019 #ifdef CONFIG_BOOT_RETRY_TIME
1021 puts("\nTimeout waiting for command\n");
1022 # ifdef CONFIG_RESET_TO_RETRY
1023 do_reset(NULL, 0, 0, NULL);
1025 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1033 n = strlen(console_buffer);
1034 console_buffer[n] = '\n';
1035 console_buffer[n+1]= '\0';
1036 if (had_ctrlc()) flag_repeat = 0;
1039 if (i->promptmode == 1) {
1040 if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1041 strcpy(the_command,console_buffer);
1044 if (console_buffer[0] != '\n') {
1045 strcpy(the_command,console_buffer);
1055 if (console_buffer[0] != '\n') {
1056 if (strlen(the_command) + strlen(console_buffer)
1057 < CONFIG_SYS_CBSIZE) {
1058 n = strlen(the_command);
1059 the_command[n-1] = ' ';
1060 strcpy(&the_command[n],console_buffer);
1063 the_command[0] = '\n';
1064 the_command[1] = '\0';
1068 if (i->__promptme == 0) {
1069 the_command[0] = '\n';
1070 the_command[1] = '\0';
1072 i->p = console_buffer;
1077 /* This is the magic location that prints prompts
1078 * and gets data back from the user */
1079 static int file_get(struct in_str *i)
1084 /* If there is data waiting, eat it up */
1085 if (i->p && *i->p) {
1088 /* need to double check i->file because we might be doing something
1089 * more complicated by now, like sourcing or substituting. */
1091 if (i->__promptme && interactive && i->file == stdin) {
1092 while(! i->p || (interactive && strlen(i->p)==0) ) {
1094 while(! i->p || strlen(i->p)==0 ) {
1102 if (i->p && *i->p) {
1107 ch = fgetc(i->file);
1111 debug_printf("b_getch: got a %d\n", ch);
1114 if (ch == '\n') i->__promptme=1;
1119 /* All the callers guarantee this routine will never be
1120 * used right after a newline, so prompting is not needed.
1122 static int file_peek(struct in_str *i)
1125 if (i->p && *i->p) {
1130 i->peek_buf[0] = fgetc(i->file);
1131 i->peek_buf[1] = '\0';
1133 debug_printf("b_peek: got a %d\n", *i->p);
1140 static void setup_file_in_str(struct in_str *i, FILE *f)
1142 static void setup_file_in_str(struct in_str *i)
1145 i->peek = file_peek;
1155 static void setup_string_in_str(struct in_str *i, const char *s)
1157 i->peek = static_peek;
1158 i->get = static_get;
1165 static void mark_open(int fd)
1167 struct close_me *new = xmalloc(sizeof(struct close_me));
1169 new->next = close_me_head;
1170 close_me_head = new;
1173 static void mark_closed(int fd)
1175 struct close_me *tmp;
1176 if (close_me_head == NULL || close_me_head->fd != fd)
1177 error_msg_and_die("corrupt close_me");
1178 tmp = close_me_head;
1179 close_me_head = close_me_head->next;
1183 static void close_all(void)
1186 for (c=close_me_head; c; c=c->next) {
1189 close_me_head = NULL;
1192 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1193 * and stderr if they are redirected. */
1194 static int setup_redirects(struct child_prog *prog, int squirrel[])
1197 struct redir_struct *redir;
1199 for (redir=prog->redirects; redir; redir=redir->next) {
1200 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1201 /* something went wrong in the parse. Pretend it didn't happen */
1204 if (redir->dup == -1) {
1205 mode=redir_table[redir->type].mode;
1206 openfd = open(redir->word.gl_pathv[0], mode, 0666);
1208 /* this could get lost if stderr has been redirected, but
1209 bash and ash both lose it as well (though zsh doesn't!) */
1210 perror_msg("error opening %s", redir->word.gl_pathv[0]);
1214 openfd = redir->dup;
1217 if (openfd != redir->fd) {
1218 if (squirrel && redir->fd < 3) {
1219 squirrel[redir->fd] = dup(redir->fd);
1224 dup2(openfd, redir->fd);
1225 if (redir->dup == -1)
1233 static void restore_redirects(int squirrel[])
1236 for (i=0; i<3; i++) {
1239 /* No error checking. I sure wouldn't know what
1240 * to do with an error if I found one! */
1248 /* XXX no exit() here. If you don't exec, use _exit instead.
1249 * The at_exit handlers apparently confuse the calling process,
1250 * in particular stdin handling. Not sure why? */
1251 static void pseudo_exec(struct child_prog *child)
1255 struct built_in_command *x;
1257 for (i=0; is_assignment(child->argv[i]); i++) {
1258 debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1259 p = insert_var_value(child->argv[i]);
1261 if (p != child->argv[i]) free(p);
1263 child->argv+=i; /* XXX this hack isn't so horrible, since we are about
1264 to exit, and therefore don't need to keep data
1265 structures consistent for free() use. */
1266 /* If a variable is assigned in a forest, and nobody listens,
1267 * was it ever really set?
1269 if (child->argv[0] == NULL) {
1270 _exit(EXIT_SUCCESS);
1274 * Check if the command matches any of the builtins.
1275 * Depending on context, this might be redundant. But it's
1276 * easier to waste a few CPU cycles than it is to figure out
1277 * if this is one of those cases.
1279 for (x = bltins; x->cmd; x++) {
1280 if (strcmp(child->argv[0], x->cmd) == 0 ) {
1281 debug_printf("builtin exec %s\n", child->argv[0]);
1282 rcode = x->function(child);
1288 /* Check if the command matches any busybox internal commands
1290 * FIXME: This feature is not 100% safe, since
1291 * BusyBox is not fully reentrant, so we have no guarantee the things
1292 * from the .bss are still zeroed, or that things from .data are still
1293 * at their defaults. We could exec ourself from /proc/self/exe, but I
1294 * really dislike relying on /proc for things. We could exec ourself
1295 * from global_argv[0], but if we are in a chroot, we may not be able
1296 * to find ourself... */
1297 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1300 char** argv_l=child->argv;
1301 char *name = child->argv[0];
1303 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1304 /* Following discussions from November 2000 on the busybox mailing
1305 * list, the default configuration, (without
1306 * get_last_path_component()) lets the user force use of an
1307 * external command by specifying the full (with slashes) filename.
1308 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1309 * _aways_ override external commands, so if you want to run
1310 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1311 * filesystem and is _not_ busybox. Some systems may want this,
1313 name = get_last_path_component(name);
1315 /* Count argc for use in a second... */
1316 for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1318 debug_printf("running applet %s\n", name);
1319 run_applet_by_name(name, argc_l, child->argv);
1322 debug_printf("exec of %s\n",child->argv[0]);
1323 execvp(child->argv[0],child->argv);
1324 perror_msg("couldn't exec: %s",child->argv[0]);
1326 } else if (child->group) {
1327 debug_printf("runtime nesting to group\n");
1328 interactive=0; /* crucial!!!! */
1329 rcode = run_list_real(child->group);
1330 /* OK to leak memory by not calling free_pipe_list,
1331 * since this process is about to exit */
1334 /* Can happen. See what bash does with ">foo" by itself. */
1335 debug_printf("trying to pseudo_exec null command\n");
1336 _exit(EXIT_SUCCESS);
1340 static void insert_bg_job(struct pipe *pi)
1342 struct pipe *thejob;
1344 /* Linear search for the ID of the job to use */
1346 for (thejob = job_list; thejob; thejob = thejob->next)
1347 if (thejob->jobid >= pi->jobid)
1348 pi->jobid = thejob->jobid + 1;
1350 /* add thejob to the list of running jobs */
1352 thejob = job_list = xmalloc(sizeof(*thejob));
1354 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1355 thejob->next = xmalloc(sizeof(*thejob));
1356 thejob = thejob->next;
1359 /* physically copy the struct job */
1360 memcpy(thejob, pi, sizeof(struct pipe));
1361 thejob->next = NULL;
1362 thejob->running_progs = thejob->num_progs;
1363 thejob->stopped_progs = 0;
1364 thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1366 /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1368 char *bar=thejob->text;
1369 char **foo=pi->progs[0].argv;
1370 while(foo && *foo) {
1371 bar += sprintf(bar, "%s ", *foo++);
1375 /* we don't wait for background thejobs to return -- append it
1376 to the list of backgrounded thejobs and leave it alone */
1377 printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1378 last_bg_pid = thejob->progs[0].pid;
1379 last_jobid = thejob->jobid;
1382 /* remove a backgrounded job */
1383 static void remove_bg_job(struct pipe *pi)
1385 struct pipe *prev_pipe;
1387 if (pi == job_list) {
1388 job_list = pi->next;
1390 prev_pipe = job_list;
1391 while (prev_pipe->next != pi)
1392 prev_pipe = prev_pipe->next;
1393 prev_pipe->next = pi->next;
1396 last_jobid = job_list->jobid;
1400 pi->stopped_progs = 0;
1405 /* Checks to see if any processes have exited -- if they
1406 have, figure out why and see if a job has completed */
1407 static int checkjobs(struct pipe* fg_pipe)
1415 attributes = WUNTRACED;
1416 if (fg_pipe==NULL) {
1417 attributes |= WNOHANG;
1420 while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1423 for (i=0; i < fg_pipe->num_progs; i++) {
1424 if (fg_pipe->progs[i].pid == childpid) {
1425 if (i==fg_pipe->num_progs-1)
1426 rcode=WEXITSTATUS(status);
1427 (fg_pipe->num_progs)--;
1433 for (pi = job_list; pi; pi = pi->next) {
1435 while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1438 if (prognum < pi->num_progs)
1443 debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1447 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1449 pi->running_progs--;
1450 pi->progs[prognum].pid = 0;
1452 if (!pi->running_progs) {
1453 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1458 pi->stopped_progs++;
1459 pi->progs[prognum].is_stopped = 1;
1462 /* Printing this stuff is a pain, since it tends to
1463 * overwrite the prompt an inconveinient moments. So
1465 if (pi->stopped_progs == pi->num_progs) {
1466 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1472 if (childpid == -1 && errno != ECHILD)
1473 perror_msg("waitpid");
1475 /* move the shell to the foreground */
1476 /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1477 /* perror_msg("tcsetpgrp-2"); */
1481 /* Figure out our controlling tty, checking in order stderr,
1482 * stdin, and stdout. If check_pgrp is set, also check that
1483 * we belong to the foreground process group associated with
1484 * that tty. The value of shell_terminal is needed in order to call
1485 * tcsetpgrp(shell_terminal, ...); */
1486 void controlling_tty(int check_pgrp)
1490 if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1491 && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1492 && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1493 goto shell_terminal_error;
1495 if (check_pgrp && curpgrp != getpgid(0))
1496 goto shell_terminal_error;
1500 shell_terminal_error:
1501 shell_terminal = -1;
1506 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1507 * to finish. See checkjobs().
1509 * return code is normally -1, when the caller has to wait for children
1510 * to finish to determine the exit status of the pipe. If the pipe
1511 * is a simple builtin command, however, the action is done by the
1512 * time run_pipe_real returns, and the exit code is provided as the
1515 * The input of the pipe is always stdin, the output is always
1516 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1517 * because it tries to avoid running the command substitution in
1518 * subshell, when that is in fact necessary. The subshell process
1519 * now has its stdout directed to the input of the appropriate pipe,
1520 * so this routine is noticeably simpler.
1522 static int run_pipe_real(struct pipe *pi)
1526 int nextin, nextout;
1527 int pipefds[2]; /* pipefds[0] is for reading */
1528 struct child_prog *child;
1529 struct built_in_command *x;
1532 /* Avoid longjmp clobbering */
1540 int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1541 struct child_prog *child;
1545 /* Avoid longjmp clobbering */
1550 #endif /* __U_BOOT__ */
1557 /* Check if this is a simple builtin (not part of a pipe).
1558 * Builtins within pipes have to fork anyway, and are handled in
1559 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1561 if (pi->num_progs == 1) child = & (pi->progs[0]);
1563 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1564 int squirrel[] = {-1, -1, -1};
1566 debug_printf("non-subshell grouping\n");
1567 setup_redirects(child, squirrel);
1568 /* XXX could we merge code with following builtin case,
1569 * by creating a pseudo builtin that calls run_list_real? */
1570 rcode = run_list_real(child->group);
1571 restore_redirects(squirrel);
1573 if (pi->num_progs == 1 && child->group) {
1575 debug_printf("non-subshell grouping\n");
1576 rcode = run_list_real(child->group);
1579 } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1580 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1581 if (i!=0 && child->argv[i]==NULL) {
1582 /* assignments, but no command: set the local environment */
1583 for (i=0; child->argv[i]!=NULL; i++) {
1585 /* Ok, this case is tricky. We have to decide if this is a
1586 * local variable, or an already exported variable. If it is
1587 * already exported, we have to export the new value. If it is
1588 * not exported, we need only set this as a local variable.
1589 * This junk is all to decide whether or not to export this
1593 name = xstrdup(child->argv[i]);
1594 debug_printf("Local environment set: %s\n", name);
1595 value = strchr(name, '=');
1599 if ( get_local_var(name)) {
1604 p = insert_var_value(child->argv[i]);
1605 set_local_var(p, export_me);
1606 if (p != child->argv[i]) free(p);
1608 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1610 for (i = 0; is_assignment(child->argv[i]); i++) {
1611 p = insert_var_value(child->argv[i]);
1615 set_local_var(p, 0);
1617 if (p != child->argv[i]) {
1625 str = make_string((child->argv + i));
1626 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1628 return last_return_code;
1631 for (x = bltins; x->cmd; x++) {
1632 if (strcmp(child->argv[i], x->cmd) == 0 ) {
1633 int squirrel[] = {-1, -1, -1};
1635 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1636 debug_printf("magic exec\n");
1637 setup_redirects(child,NULL);
1638 return EXIT_SUCCESS;
1640 debug_printf("builtin inline %s\n", child->argv[0]);
1641 /* XXX setup_redirects acts on file descriptors, not FILEs.
1642 * This is perfect for work that comes after exec().
1643 * Is it really safe for inline use? Experimentally,
1644 * things seem to work with glibc. */
1645 setup_redirects(child, squirrel);
1647 /* check ";", because ,example , argv consist from
1648 * "help;flinfo" must not execute
1650 if (strchr(child->argv[i], ';')) {
1651 printf ("Unknown command '%s' - try 'help' or use 'run' command\n",
1655 /* Look up command in command table */
1658 if ((cmdtp = find_cmd(child->argv[i])) == NULL) {
1659 printf ("Unknown command '%s' - try 'help'\n", child->argv[i]);
1660 return -1; /* give up after bad command */
1663 #if defined(CONFIG_CMD_BOOTD)
1664 /* avoid "bootd" recursion */
1665 if (cmdtp->cmd == do_bootd) {
1666 if (flag & CMD_FLAG_BOOTD) {
1667 printf ("'bootd' recursion detected\n");
1671 flag |= CMD_FLAG_BOOTD;
1674 /* found - check max args */
1675 if ((child->argc - i) > cmdtp->maxargs)
1676 return cmd_usage(cmdtp);
1678 child->argv+=i; /* XXX horrible hack */
1680 rcode = x->function(child);
1682 /* OK - call function to do the command */
1684 rcode = (cmdtp->cmd)
1685 (cmdtp, flag,child->argc-i,&child->argv[i]);
1686 if ( !cmdtp->repeatable )
1691 child->argv-=i; /* XXX restore hack so free() can work right */
1694 restore_redirects(squirrel);
1703 for (i = 0; i < pi->num_progs; i++) {
1704 child = & (pi->progs[i]);
1706 /* pipes are inserted between pairs of commands */
1707 if ((i + 1) < pi->num_progs) {
1708 if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1709 nextout = pipefds[1];
1715 /* XXX test for failed fork()? */
1716 if (!(child->pid = fork())) {
1717 /* Set the handling for job control signals back to the default. */
1718 signal(SIGINT, SIG_DFL);
1719 signal(SIGQUIT, SIG_DFL);
1720 signal(SIGTERM, SIG_DFL);
1721 signal(SIGTSTP, SIG_DFL);
1722 signal(SIGTTIN, SIG_DFL);
1723 signal(SIGTTOU, SIG_DFL);
1724 signal(SIGCHLD, SIG_DFL);
1736 if (pipefds[0]!=-1) {
1737 close(pipefds[0]); /* opposite end of our output pipe */
1740 /* Like bash, explicit redirects override pipes,
1741 * and the pipe fd is available for dup'ing. */
1742 setup_redirects(child,NULL);
1744 if (interactive && pi->followup!=PIPE_BG) {
1745 /* If we (the child) win the race, put ourselves in the process
1746 * group whose leader is the first process in this pipe. */
1748 pi->pgrp = getpid();
1750 if (setpgid(0, pi->pgrp) == 0) {
1751 tcsetpgrp(2, pi->pgrp);
1759 /* put our child in the process group whose leader is the
1760 first process in this pipe */
1762 pi->pgrp = child->pid;
1764 /* Don't check for errors. The child may be dead already,
1765 * in which case setpgid returns error code EACCES. */
1766 setpgid(child->pid, pi->pgrp);
1773 /* If there isn't another process, nextin is garbage
1774 but it doesn't matter */
1775 nextin = pipefds[0];
1781 static int run_list_real(struct pipe *pi)
1783 char *save_name = NULL;
1785 char **save_list = NULL;
1791 int rcode=0, flag_skip=1;
1792 int flag_restore = 0;
1793 int if_code=0, next_if_code=0; /* need double-buffer to handle elif */
1794 reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1795 /* check syntax for "for" */
1796 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1797 if ((rpipe->r_mode == RES_IN ||
1798 rpipe->r_mode == RES_FOR) &&
1799 (rpipe->next == NULL)) {
1806 if ((rpipe->r_mode == RES_IN &&
1807 (rpipe->next->r_mode == RES_IN &&
1808 rpipe->next->progs->argv != NULL))||
1809 (rpipe->r_mode == RES_FOR &&
1810 rpipe->next->r_mode != RES_IN)) {
1818 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1819 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1820 pi->r_mode == RES_FOR) {
1824 if ((had_ctrlc())) {
1835 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);
1836 if (rmode == skip_more_in_this_rmode && flag_skip) {
1837 if (pi->followup == PIPE_SEQ) flag_skip=0;
1841 skip_more_in_this_rmode = RES_XXXX;
1842 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1843 if (rmode == RES_THEN && if_code) continue;
1844 if (rmode == RES_ELSE && !if_code) continue;
1845 if (rmode == RES_ELIF && !if_code) break;
1846 if (rmode == RES_FOR && pi->num_progs) {
1848 /* if no variable values after "in" we skip "for" */
1849 if (!pi->next->progs->argv) continue;
1850 /* create list of variable values */
1851 list = make_list_in(pi->next->progs->argv,
1852 pi->progs->argv[0]);
1854 save_name = pi->progs->argv[0];
1855 pi->progs->argv[0] = NULL;
1859 free(pi->progs->argv[0]);
1863 pi->progs->argv[0] = save_name;
1865 pi->progs->glob_result.gl_pathv[0] =
1870 /* insert new value from list for variable */
1871 if (pi->progs->argv[0])
1872 free(pi->progs->argv[0]);
1873 pi->progs->argv[0] = *list++;
1875 pi->progs->glob_result.gl_pathv[0] =
1880 if (rmode == RES_IN) continue;
1881 if (rmode == RES_DO) {
1882 if (!flag_rep) continue;
1884 if ((rmode == RES_DONE)) {
1891 if (pi->num_progs == 0) continue;
1893 save_num_progs = pi->num_progs; /* save number of programs */
1895 rcode = run_pipe_real(pi);
1896 debug_printf("run_pipe_real returned %d\n",rcode);
1899 /* We only ran a builtin: rcode was set by the return value
1900 * of run_pipe_real(), and we don't need to wait for anything. */
1901 } else if (pi->followup==PIPE_BG) {
1902 /* XXX check bash's behavior with nontrivial pipes */
1903 /* XXX compute jobid */
1904 /* XXX what does bash do with attempts to background builtins? */
1906 rcode = EXIT_SUCCESS;
1909 /* move the new process group into the foreground */
1910 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1911 perror_msg("tcsetpgrp-3");
1912 rcode = checkjobs(pi);
1913 /* move the shell to the foreground */
1914 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1915 perror_msg("tcsetpgrp-4");
1917 rcode = checkjobs(pi);
1919 debug_printf("checkjobs returned %d\n",rcode);
1921 last_return_code=rcode;
1924 last_return_code = -rcode - 2;
1925 return -2; /* exit */
1927 last_return_code=(rcode == 0) ? 0 : 1;
1930 pi->num_progs = save_num_progs; /* restore number of programs */
1932 if ( rmode == RES_IF || rmode == RES_ELIF )
1933 next_if_code=rcode; /* can be overwritten a number of times */
1934 if (rmode == RES_WHILE)
1935 flag_rep = !last_return_code;
1936 if (rmode == RES_UNTIL)
1937 flag_rep = last_return_code;
1938 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1939 (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1940 skip_more_in_this_rmode=rmode;
1948 /* broken, of course, but OK for testing */
1949 static char *indenter(int i)
1951 static char blanks[]=" ";
1952 return &blanks[sizeof(blanks)-i-1];
1955 /* return code is the exit status of the pipe */
1956 static int free_pipe(struct pipe *pi, int indent)
1959 struct child_prog *child;
1961 struct redir_struct *r, *rnext;
1963 int a, i, ret_code=0;
1964 char *ind = indenter(indent);
1967 if (pi->stopped_progs > 0)
1969 final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1971 for (i=0; i<pi->num_progs; i++) {
1972 child = &pi->progs[i];
1973 final_printf("%s command %d:\n",ind,i);
1975 for (a=0,p=child->argv; *p; a++,p++) {
1976 final_printf("%s argv[%d] = %s\n",ind,a,*p);
1979 globfree(&child->glob_result);
1981 for (a = 0; a < child->argc; a++) {
1982 free(child->argv[a]);
1988 } else if (child->group) {
1990 final_printf("%s begin group (subshell:%d)\n",ind, child->subshell);
1992 ret_code = free_pipe_list(child->group,indent+3);
1993 final_printf("%s end group\n",ind);
1995 final_printf("%s (nil)\n",ind);
1998 for (r=child->redirects; r; r=rnext) {
1999 final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
2001 /* guard against the case >$FOO, where foo is unset or blank */
2002 if (r->word.gl_pathv) {
2003 final_printf(" %s\n", *r->word.gl_pathv);
2007 final_printf("&%d\n", r->dup);
2012 child->redirects=NULL;
2015 free(pi->progs); /* children are an array, they get freed all at once */
2020 static int free_pipe_list(struct pipe *head, int indent)
2022 int rcode=0; /* if list has no members */
2023 struct pipe *pi, *next;
2024 char *ind = indenter(indent);
2025 for (pi=head; pi; pi=next) {
2026 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
2027 rcode = free_pipe(pi, indent);
2028 final_printf("%s pipe followup code %d\n", ind, pi->followup);
2036 /* Select which version we will use */
2037 static int run_list(struct pipe *pi)
2043 rcode = run_list_real(pi);
2047 /* free_pipe_list has the side effect of clearing memory
2048 * In the long run that function can be merged with run_list_real,
2049 * but doing that now would hobble the debugging effort. */
2050 free_pipe_list(pi,0);
2054 /* The API for glob is arguably broken. This routine pushes a non-matching
2055 * string into the output structure, removing non-backslashed backslashes.
2056 * If someone can prove me wrong, by performing this function within the
2057 * original glob(3) api, feel free to rewrite this routine into oblivion.
2058 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2059 * XXX broken if the last character is '\\', check that before calling.
2062 static int globhack(const char *src, int flags, glob_t *pglob)
2067 for (cnt=1, s=src; s && *s; s++) {
2068 if (*s == '\\') s++;
2072 if (!dest) return GLOB_NOSPACE;
2073 if (!(flags & GLOB_APPEND)) {
2074 pglob->gl_pathv=NULL;
2079 pathc = ++pglob->gl_pathc;
2080 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2081 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2082 pglob->gl_pathv[pathc-1]=dest;
2083 pglob->gl_pathv[pathc]=NULL;
2084 for (s=src; s && *s; s++, dest++) {
2085 if (*s == '\\') s++;
2092 /* XXX broken if the last character is '\\', check that before calling */
2093 static int glob_needed(const char *s)
2096 if (*s == '\\') s++;
2097 if (strchr("*[?",*s)) return 1;
2103 static void globprint(glob_t *pglob)
2106 debug_printf("glob_t at %p:\n", pglob);
2107 debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
2108 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2109 for (i=0; i<pglob->gl_pathc; i++)
2110 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2111 pglob->gl_pathv[i], pglob->gl_pathv[i]);
2115 static int xglob(o_string *dest, int flags, glob_t *pglob)
2119 /* short-circuit for null word */
2120 /* we can code this better when the debug_printf's are gone */
2121 if (dest->length == 0) {
2122 if (dest->nonnull) {
2123 /* bash man page calls this an "explicit" null */
2124 gr = globhack(dest->data, flags, pglob);
2125 debug_printf("globhack returned %d\n",gr);
2129 } else if (glob_needed(dest->data)) {
2130 gr = glob(dest->data, flags, NULL, pglob);
2131 debug_printf("glob returned %d\n",gr);
2132 if (gr == GLOB_NOMATCH) {
2133 /* quote removal, or more accurately, backslash removal */
2134 gr = globhack(dest->data, flags, pglob);
2135 debug_printf("globhack returned %d\n",gr);
2138 gr = globhack(dest->data, flags, pglob);
2139 debug_printf("globhack returned %d\n",gr);
2141 if (gr == GLOB_NOSPACE)
2142 error_msg_and_die("out of memory during glob");
2143 if (gr != 0) { /* GLOB_ABORTED ? */
2144 error_msg("glob(3) error %d",gr);
2146 /* globprint(glob_target); */
2152 static char *get_dollar_var(char ch);
2155 /* This is used to get/check local shell variables */
2156 char *get_local_var(const char *s)
2158 struct variables *cur;
2165 return get_dollar_var(s[1]);
2168 for (cur = top_vars; cur; cur=cur->next)
2169 if(strcmp(cur->name, s)==0)
2174 /* This is used to set local shell variables
2175 flg_export==0 if only local (not exporting) variable
2176 flg_export==1 if "new" exporting environ
2177 flg_export>1 if current startup environ (not call putenv()) */
2178 int set_local_var(const char *s, int flg_export)
2182 struct variables *cur;
2185 /* might be possible! */
2193 if (getenv(name) != NULL) {
2195 "There is a global environment variable with the same name.\n");
2200 /* Assume when we enter this function that we are already in
2201 * NAME=VALUE format. So the first order of business is to
2202 * split 's' on the '=' into 'name' and 'value' */
2203 value = strchr(name, '=');
2204 if (value==0 && ++value==0) {
2210 for(cur = top_vars; cur; cur = cur->next) {
2211 if(strcmp(cur->name, name)==0)
2216 if(strcmp(cur->value, value)==0) {
2217 if(flg_export>0 && cur->flg_export==0)
2218 cur->flg_export=flg_export;
2222 if(cur->flg_read_only) {
2223 error_msg("%s: readonly variable", name);
2226 if(flg_export>0 || cur->flg_export>1)
2230 cur->value = strdup(value);
2234 cur = malloc(sizeof(struct variables));
2238 cur->name = strdup(name);
2239 if(cur->name == 0) {
2243 struct variables *bottom = top_vars;
2244 cur->value = strdup(value);
2246 cur->flg_export = flg_export;
2247 cur->flg_read_only = 0;
2248 while(bottom->next) bottom=bottom->next;
2255 if(result==0 && cur->flg_export==1) {
2257 result = putenv(name);
2262 if(result>0) /* equivalent to previous set */
2269 void unset_local_var(const char *name)
2271 struct variables *cur;
2274 for (cur = top_vars; cur; cur=cur->next) {
2275 if(strcmp(cur->name, name)==0)
2279 struct variables *next = top_vars;
2280 if(cur->flg_read_only) {
2281 error_msg("%s: readonly variable", name);
2286 unsetenv(cur->name);
2290 while (next->next != cur)
2292 next->next = cur->next;
2299 static int is_assignment(const char *s)
2304 if (!isalpha(*s)) return 0;
2306 while(isalnum(*s) || *s=='_') ++s;
2311 /* the src parameter allows us to peek forward to a possible &n syntax
2312 * for file descriptor duplication, e.g., "2>&1".
2313 * Return code is 0 normally, 1 if a syntax error is detected in src.
2314 * Resource errors (in xmalloc) cause the process to exit */
2315 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2316 struct in_str *input)
2318 struct child_prog *child=ctx->child;
2319 struct redir_struct *redir = child->redirects;
2320 struct redir_struct *last_redir=NULL;
2322 /* Create a new redir_struct and drop it onto the end of the linked list */
2327 redir = xmalloc(sizeof(struct redir_struct));
2329 redir->word.gl_pathv=NULL;
2331 last_redir->next=redir;
2333 child->redirects=redir;
2337 redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2339 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2341 /* Check for a '2>&1' type redirect */
2342 redir->dup = redirect_dup_num(input);
2343 if (redir->dup == -2) return 1; /* syntax error */
2344 if (redir->dup != -1) {
2345 /* Erik had a check here that the file descriptor in question
2346 * is legit; I postpone that to "run time"
2347 * A "-" representation of "close me" shows up as a -3 here */
2348 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2350 /* We do _not_ try to open the file that src points to,
2351 * since we need to return and let src be expanded first.
2352 * Set ctx->pending_redirect, so we know what to do at the
2353 * end of the next parsed word.
2355 ctx->pending_redirect = redir;
2361 struct pipe *new_pipe(void) {
2363 pi = xmalloc(sizeof(struct pipe));
2367 pi->followup = 0; /* invalid */
2368 pi->r_mode = RES_NONE;
2372 static void initialize_context(struct p_context *ctx)
2376 ctx->pending_redirect=NULL;
2379 ctx->list_head=new_pipe();
2380 ctx->pipe=ctx->list_head;
2386 done_command(ctx); /* creates the memory for working child */
2389 /* normal return is 0
2390 * if a reserved word is found, and processed, return 1
2391 * should handle if, then, elif, else, fi, for, while, until, do, done.
2392 * case, function, and select are obnoxious, save those for later.
2394 struct reserved_combo {
2399 /* Mostly a list of accepted follow-up reserved words.
2400 * FLAG_END means we are done with the sequence, and are ready
2401 * to turn the compound list into a command.
2402 * FLAG_START means the word must start a new compound list.
2404 static struct reserved_combo reserved_list[] = {
2405 { "if", RES_IF, FLAG_THEN | FLAG_START },
2406 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2407 { "elif", RES_ELIF, FLAG_THEN },
2408 { "else", RES_ELSE, FLAG_FI },
2409 { "fi", RES_FI, FLAG_END },
2410 { "for", RES_FOR, FLAG_IN | FLAG_START },
2411 { "while", RES_WHILE, FLAG_DO | FLAG_START },
2412 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
2413 { "in", RES_IN, FLAG_DO },
2414 { "do", RES_DO, FLAG_DONE },
2415 { "done", RES_DONE, FLAG_END }
2417 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2419 int reserved_word(o_string *dest, struct p_context *ctx)
2421 struct reserved_combo *r;
2422 for (r=reserved_list;
2423 r<reserved_list+NRES; r++) {
2424 if (strcmp(dest->data, r->literal) == 0) {
2425 debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2426 if (r->flag & FLAG_START) {
2427 struct p_context *new = xmalloc(sizeof(struct p_context));
2428 debug_printf("push stack\n");
2429 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2436 *new = *ctx; /* physical copy */
2437 initialize_context(ctx);
2439 } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2446 ctx->old_flag = r->flag;
2447 if (ctx->old_flag & FLAG_END) {
2448 struct p_context *old;
2449 debug_printf("pop stack\n");
2450 done_pipe(ctx,PIPE_SEQ);
2452 old->child->group = ctx->list_head;
2454 old->child->subshell = 0;
2456 *ctx = *old; /* physical copy */
2466 /* normal return is 0.
2467 * Syntax or xglob errors return 1. */
2468 static int done_word(o_string *dest, struct p_context *ctx)
2470 struct child_prog *child=ctx->child;
2472 glob_t *glob_target;
2479 debug_printf("done_word: %s %p\n", dest->data, child);
2480 if (dest->length == 0 && !dest->nonnull) {
2481 debug_printf(" true null, ignored\n");
2485 if (ctx->pending_redirect) {
2486 glob_target = &ctx->pending_redirect->word;
2491 return 1; /* syntax error, groups and arglists don't mix */
2493 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2494 debug_printf("checking %s for reserved-ness\n",dest->data);
2495 if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2498 glob_target = &child->glob_result;
2499 if (child->argv) flags |= GLOB_APPEND;
2501 for (cnt = 1, s = dest->data; s && *s; s++) {
2502 if (*s == '\\') s++;
2507 if ( child->argv == NULL) {
2510 argc = ++child->argc;
2511 child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2512 if (child->argv == NULL) return 1;
2513 child->argv[argc-1]=str;
2514 child->argv[argc]=NULL;
2515 for (s = dest->data; s && *s; s++,str++) {
2516 if (*s == '\\') s++;
2523 gr = xglob(dest, flags, glob_target);
2524 if (gr != 0) return 1;
2529 if (ctx->pending_redirect) {
2530 ctx->pending_redirect=NULL;
2531 if (glob_target->gl_pathc != 1) {
2532 error_msg("ambiguous redirect");
2536 child->argv = glob_target->gl_pathv;
2539 if (ctx->w == RES_FOR) {
2540 done_word(dest,ctx);
2541 done_pipe(ctx,PIPE_SEQ);
2546 /* The only possible error here is out of memory, in which case
2548 static int done_command(struct p_context *ctx)
2550 /* The child is really already in the pipe structure, so
2551 * advance the pipe counter and make a new, null child.
2552 * Only real trickiness here is that the uncommitted
2553 * child structure, to which ctx->child points, is not
2554 * counted in pi->num_progs. */
2555 struct pipe *pi=ctx->pipe;
2556 struct child_prog *prog=ctx->child;
2558 if (prog && prog->group == NULL
2559 && prog->argv == NULL
2561 && prog->redirects == NULL) {
2565 debug_printf("done_command: skipping null command\n");
2569 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2571 debug_printf("done_command: initializing\n");
2573 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2575 prog = pi->progs + pi->num_progs;
2577 prog->redirects = NULL;
2581 prog->is_stopped = 0;
2585 prog->glob_result.gl_pathv = NULL;
2590 prog->type = ctx->type;
2592 /* but ctx->pipe and ctx->list_head remain unchanged */
2596 static int done_pipe(struct p_context *ctx, pipe_style type)
2599 done_command(ctx); /* implicit closure of previous command */
2600 debug_printf("done_pipe, type %d\n", type);
2601 ctx->pipe->followup = type;
2602 ctx->pipe->r_mode = ctx->w;
2604 ctx->pipe->next = new_p;
2607 done_command(ctx); /* set up new pipe to accept commands */
2612 /* peek ahead in the in_str to find out if we have a "&n" construct,
2613 * as in "2>&1", that represents duplicating a file descriptor.
2614 * returns either -2 (syntax error), -1 (no &), or the number found.
2616 static int redirect_dup_num(struct in_str *input)
2620 if (ch != '&') return -1;
2622 b_getch(input); /* get the & */
2626 return -3; /* "-" represents "close me" */
2628 while (isdigit(ch)) {
2636 error_msg("ambiguous redirect");
2640 /* If a redirect is immediately preceded by a number, that number is
2641 * supposed to tell which file descriptor to redirect. This routine
2642 * looks for such preceding numbers. In an ideal world this routine
2643 * needs to handle all the following classes of redirects...
2644 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2645 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2646 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2647 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2648 * A -1 output from this program means no valid number was found, so the
2649 * caller should use the appropriate default for this redirection.
2651 static int redirect_opt_num(o_string *o)
2655 if (o->length==0) return -1;
2656 for(num=0; num<o->length; num++) {
2657 if (!isdigit(*(o->data+num))) {
2661 /* reuse num (and save an int) */
2667 FILE *generate_stream_from_list(struct pipe *head)
2671 int pid, channel[2];
2672 if (pipe(channel)<0) perror_msg_and_die("pipe");
2675 perror_msg_and_die("fork");
2676 } else if (pid==0) {
2678 if (channel[1] != 1) {
2683 #define SURROGATE "surrogate response"
2684 write(1,SURROGATE,sizeof(SURROGATE));
2685 _exit(run_list(head));
2687 _exit(run_list_real(head)); /* leaks memory */
2690 debug_printf("forked child %d\n",pid);
2692 pf = fdopen(channel[0],"r");
2693 debug_printf("pipe on FILE *%p\n",pf);
2695 free_pipe_list(head,0);
2696 pf=popen("echo surrogate response","r");
2697 debug_printf("started fake pipe on FILE *%p\n",pf);
2702 /* this version hacked for testing purposes */
2703 /* return code is exit status of the process that is run. */
2704 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2707 o_string result=NULL_O_STRING;
2708 struct p_context inner;
2710 struct in_str pipe_str;
2711 initialize_context(&inner);
2713 /* recursion to generate command */
2714 retcode = parse_stream(&result, &inner, input, subst_end);
2715 if (retcode != 0) return retcode; /* syntax error or EOF */
2716 done_word(&result, &inner);
2717 done_pipe(&inner, PIPE_SEQ);
2720 p=generate_stream_from_list(inner.list_head);
2721 if (p==NULL) return 1;
2722 mark_open(fileno(p));
2723 setup_file_in_str(&pipe_str, p);
2725 /* now send results of command back into original context */
2726 retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2727 /* XXX In case of a syntax error, should we try to kill the child?
2728 * That would be tough to do right, so just read until EOF. */
2730 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2733 debug_printf("done reading from pipe, pclose()ing\n");
2734 /* This is the step that wait()s for the child. Should be pretty
2735 * safe, since we just read an EOF from its stdout. We could try
2736 * to better, by using wait(), and keeping track of background jobs
2737 * at the same time. That would be a lot of work, and contrary
2738 * to the KISS philosophy of this program. */
2739 mark_closed(fileno(p));
2741 free_pipe_list(inner.list_head,0);
2742 debug_printf("pclosed, retcode=%d\n",retcode);
2743 /* XXX this process fails to trim a single trailing newline */
2747 static int parse_group(o_string *dest, struct p_context *ctx,
2748 struct in_str *input, int ch)
2751 struct p_context sub;
2752 struct child_prog *child = ctx->child;
2755 return 1; /* syntax error, groups and arglists don't mix */
2757 initialize_context(&sub);
2759 case '(': endch=')'; child->subshell=1; break;
2760 case '{': endch='}'; break;
2761 default: syntax(); /* really logic error */
2763 rcode=parse_stream(dest,&sub,input,endch);
2764 done_word(dest,&sub); /* finish off the final word in the subcontext */
2765 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2766 child->group = sub.list_head;
2768 /* child remains "open", available for possible redirects */
2772 /* basically useful version until someone wants to get fancier,
2773 * see the bash man page under "Parameter Expansion" */
2774 static char *lookup_param(char *src)
2783 p = get_local_var(src);
2789 static char *get_dollar_var(char ch)
2791 static char buf[40];
2796 sprintf(buf, "%u", (unsigned int)last_return_code);
2805 /* return code: 0 for OK, 1 for syntax error */
2806 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2816 int ch = input->peek(input); /* first character after the $ */
2817 debug_printf("handle_dollar: ch=%c\n",ch);
2819 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2821 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2825 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2827 } else if (isdigit(ch)) {
2828 i = ch-'0'; /* XXX is $0 special? */
2829 if (i<global_argc) {
2830 parse_string(dest, ctx, global_argv[i]); /* recursion */
2834 } else switch (ch) {
2837 b_adduint(dest,getpid());
2841 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2847 b_adduint(dest,last_return_code);
2850 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2851 b_addchr(dest, '$');
2852 b_addchr(dest, '?');
2853 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2859 b_adduint(dest,global_argc ? global_argc-1 : 0);
2864 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2867 /* XXX maybe someone will try to escape the '}' */
2868 while(ch=b_getch(input),ch!=EOF && ch!='}') {
2875 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2880 process_command_subs(dest, ctx, input, ')');
2884 for (i=1; i<global_argc; i++) {
2885 parse_string(dest, ctx, global_argv[i]);
2886 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2892 /* still unhandled, but should be eventually */
2893 error_msg("unhandled syntax: $%c",ch);
2898 b_addqchr(dest,'$',dest->quote);
2900 /* Eat the character if the flag was set. If the compiler
2901 * is smart enough, we could substitute "b_getch(input);"
2902 * for all the "advance = 1;" above, and also end up with
2903 * a nice size-optimized program. Hah! That'll be the day.
2905 if (advance) b_getch(input);
2910 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2913 setup_string_in_str(&foo, src);
2914 return parse_stream(dest, ctx, &foo, '\0');
2918 /* return code is 0 for normal exit, 1 for syntax error */
2919 int parse_stream(o_string *dest, struct p_context *ctx,
2920 struct in_str *input, int end_trigger)
2925 redir_type redir_style;
2929 /* Only double-quote state is handled in the state variable dest->quote.
2930 * A single-quote triggers a bypass of the main loop until its mate is
2931 * found. When recursing, quote state is passed in via dest->quote. */
2933 debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2934 while ((ch=b_getch(input))!=EOF) {
2937 if (input->__promptme == 0) return 1;
2939 next = (ch == '\n') ? 0 : b_peek(input);
2941 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2942 ch >= ' ' ? ch : '.', ch, m,
2943 dest->quote, ctx->stack == NULL ? '*' : '.');
2945 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2946 b_addqchr(dest, ch, dest->quote);
2948 if (m==2) { /* unquoted IFS */
2949 if (done_word(dest, ctx)) {
2952 /* If we aren't performing a substitution, treat a newline as a
2953 * command separator. */
2954 if (end_trigger != '\0' && ch=='\n')
2955 done_pipe(ctx,PIPE_SEQ);
2957 if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2958 debug_printf("leaving parse_stream (triggered)\n");
2963 /* Yahoo! Time to run with it! */
2964 done_pipe(ctx,PIPE_SEQ);
2965 run_list(ctx->list_head);
2966 initialize_context(ctx);
2969 if (m!=2) switch (ch) {
2971 if (dest->length == 0 && !dest->quote) {
2972 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2974 b_addqchr(dest, ch, dest->quote);
2982 b_addqchr(dest, '\\', dest->quote);
2983 b_addqchr(dest, b_getch(input), dest->quote);
2986 if (handle_dollar(dest, ctx, input)!=0) return 1;
2990 while(ch=b_getch(input),ch!=EOF && ch!='\'') {
2992 if(input->__promptme == 0) return 1;
3003 dest->quote = !dest->quote;
3007 process_command_subs(dest, ctx, input, '`');
3010 redir_fd = redirect_opt_num(dest);
3011 done_word(dest, ctx);
3012 redir_style=REDIRECT_OVERWRITE;
3014 redir_style=REDIRECT_APPEND;
3016 } else if (next == '(') {
3017 syntax(); /* until we support >(list) Process Substitution */
3020 setup_redirect(ctx, redir_fd, redir_style, input);
3023 redir_fd = redirect_opt_num(dest);
3024 done_word(dest, ctx);
3025 redir_style=REDIRECT_INPUT;
3027 redir_style=REDIRECT_HEREIS;
3029 } else if (next == '>') {
3030 redir_style=REDIRECT_IO;
3032 } else if (next == '(') {
3033 syntax(); /* until we support <(list) Process Substitution */
3036 setup_redirect(ctx, redir_fd, redir_style, input);
3040 done_word(dest, ctx);
3041 done_pipe(ctx,PIPE_SEQ);
3044 done_word(dest, ctx);
3047 done_pipe(ctx,PIPE_AND);
3050 done_pipe(ctx,PIPE_BG);
3058 done_word(dest, ctx);
3061 done_pipe(ctx,PIPE_OR);
3063 /* we could pick up a file descriptor choice here
3064 * with redirect_opt_num(), but bash doesn't do it.
3065 * "echo foo 2| cat" yields "foo 2". */
3077 if (parse_group(dest, ctx, input, ch)!=0) return 1;
3081 syntax(); /* Proper use of this character caught by end_trigger */
3086 syntax(); /* this is really an internal logic error */
3091 /* complain if quote? No, maybe we just finished a command substitution
3092 * that was quoted. Example:
3093 * $ echo "`cat foo` plus more"
3094 * and we just got the EOF generated by the subshell that ran "cat foo"
3095 * The only real complaint is if we got an EOF when end_trigger != '\0',
3096 * that is, we were really supposed to get end_trigger, and never got
3097 * one before the EOF. Can't use the standard "syntax error" return code,
3098 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3099 debug_printf("leaving parse_stream (EOF)\n");
3100 if (end_trigger != '\0') return -1;
3104 void mapset(const unsigned char *set, int code)
3106 const unsigned char *s;
3107 for (s=set; *s; s++) map[*s] = code;
3110 void update_ifs_map(void)
3112 /* char *ifs and char map[256] are both globals. */
3113 ifs = (uchar *)getenv("IFS");
3114 if (ifs == NULL) ifs=(uchar *)" \t\n";
3115 /* Precompute a list of 'flow through' behavior so it can be treated
3116 * quickly up front. Computation is necessary because of IFS.
3117 * Special case handling of IFS == " \t\n" is not implemented.
3118 * The map[] array only really needs two bits each, and on most machines
3119 * that would be faster because of the reduced L1 cache footprint.
3121 memset(map,0,sizeof(map)); /* most characters flow through always */
3123 mapset((uchar *)"\\$'\"`", 3); /* never flow through */
3124 mapset((uchar *)"<>;&|(){}#", 1); /* flow through if quoted */
3126 mapset((uchar *)"\\$'\"", 3); /* never flow through */
3127 mapset((uchar *)";&|#", 1); /* flow through if quoted */
3129 mapset(ifs, 2); /* also flow through if quoted */
3132 /* most recursion does not come through here, the exeception is
3133 * from builtin_source() */
3134 int parse_stream_outer(struct in_str *inp, int flag)
3137 struct p_context ctx;
3138 o_string temp=NULL_O_STRING;
3145 initialize_context(&ctx);
3147 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3149 rcode = parse_stream(&temp, &ctx, inp, '\n');
3151 if (rcode == 1) flag_repeat = 0;
3153 if (rcode != 1 && ctx.old_flag != 0) {
3159 if (rcode != 1 && ctx.old_flag == 0) {
3160 done_word(&temp, &ctx);
3161 done_pipe(&ctx,PIPE_SEQ);
3163 run_list(ctx.list_head);
3165 code = run_list(ctx.list_head);
3166 if (code == -2) { /* exit */
3169 /* XXX hackish way to not allow exit from main loop */
3170 if (inp->peek == file_peek) {
3171 printf("exit not allowed from main input shell.\n");
3180 if (ctx.old_flag != 0) {
3185 if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3186 inp->__promptme = 1;
3191 free_pipe_list(ctx.list_head,0);
3194 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
3198 return (code != 0) ? 1 : 0;
3199 #endif /* __U_BOOT__ */
3203 static int parse_string_outer(const char *s, int flag)
3205 int parse_string_outer(const char *s, int flag)
3206 #endif /* __U_BOOT__ */
3208 struct in_str input;
3214 if (!(p = strchr(s, '\n')) || *++p) {
3215 p = xmalloc(strlen(s) + 2);
3218 setup_string_in_str(&input, p);
3219 rcode = parse_stream_outer(&input, flag);
3224 setup_string_in_str(&input, s);
3225 return parse_stream_outer(&input, flag);
3232 static int parse_file_outer(FILE *f)
3234 int parse_file_outer(void)
3238 struct in_str input;
3240 setup_file_in_str(&input, f);
3242 setup_file_in_str(&input);
3244 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3249 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3250 static void u_boot_hush_reloc(void)
3253 struct reserved_combo *r;
3255 for (r=reserved_list; r<reserved_list+NRES; r++) {
3256 addr = (ulong) (r->literal) + gd->reloc_off;
3257 r->literal = (char *)addr;
3262 int u_boot_hush_start(void)
3264 if (top_vars == NULL) {
3265 top_vars = malloc(sizeof(struct variables));
3266 top_vars->name = "HUSH_VERSION";
3267 top_vars->value = "0.01";
3269 top_vars->flg_export = 0;
3270 top_vars->flg_read_only = 1;
3271 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3272 u_boot_hush_reloc();
3278 static void *xmalloc(size_t size)
3282 if (!(p = malloc(size))) {
3283 printf("ERROR : memory not allocated\n");
3289 static void *xrealloc(void *ptr, size_t size)
3293 if (!(p = realloc(ptr, size))) {
3294 printf("ERROR : memory not allocated\n");
3299 #endif /* __U_BOOT__ */
3302 /* Make sure we have a controlling tty. If we get started under a job
3303 * aware app (like bash for example), make sure we are now in charge so
3304 * we don't fight over who gets the foreground */
3305 static void setup_job_control(void)
3307 static pid_t shell_pgrp;
3308 /* Loop until we are in the foreground. */
3309 while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3310 kill (- shell_pgrp, SIGTTIN);
3312 /* Ignore interactive and job-control signals. */
3313 signal(SIGINT, SIG_IGN);
3314 signal(SIGQUIT, SIG_IGN);
3315 signal(SIGTERM, SIG_IGN);
3316 signal(SIGTSTP, SIG_IGN);
3317 signal(SIGTTIN, SIG_IGN);
3318 signal(SIGTTOU, SIG_IGN);
3319 signal(SIGCHLD, SIG_IGN);
3321 /* Put ourselves in our own process group. */
3323 shell_pgrp = getpid ();
3324 setpgid (shell_pgrp, shell_pgrp);
3326 /* Grab control of the terminal. */
3327 tcsetpgrp(shell_terminal, shell_pgrp);
3330 int hush_main(int argc, char * const *argv)
3336 /* XXX what should these be while sourcing /etc/profile? */
3340 /* (re?) initialize globals. Sometimes hush_main() ends up calling
3341 * hush_main(), therefore we cannot rely on the BSS to zero out this
3342 * stuff. Reset these to 0 every time. */
3344 /* map[] is taken care of with call to update_ifs_map() */
3347 close_me_head = NULL;
3352 /* Initialize some more globals to non-zero values */
3354 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3355 cmdedit_set_initial_prompt();
3361 /* initialize our shell local variables with the values
3362 * currently living in the environment */
3365 set_local_var(*e, 2); /* without call putenv() */
3368 last_return_code=EXIT_SUCCESS;
3371 if (argv[0] && argv[0][0] == '-') {
3372 debug_printf("\nsourcing /etc/profile\n");
3373 if ((input = fopen("/etc/profile", "r")) != NULL) {
3374 mark_open(fileno(input));
3375 parse_file_outer(input);
3376 mark_closed(fileno(input));
3382 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3386 global_argv = argv+optind;
3387 global_argc = argc-optind;
3388 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3400 fprintf(stderr, "Usage: sh [FILE]...\n"
3401 " or: sh -c command [args]...\n\n");
3408 /* A shell is interactive if the `-i' flag was given, or if all of
3409 * the following conditions are met:
3411 * no arguments remaining or the -s flag given
3412 * standard input is a terminal
3413 * standard output is a terminal
3414 * Refer to Posix.2, the description of the `sh' utility. */
3415 if (argv[optind]==NULL && input==stdin &&
3416 isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3420 debug_printf("\ninteractive=%d\n", interactive);
3422 /* Looks like they want an interactive shell */
3423 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3424 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3425 printf( "Enter 'help' for a list of built-in commands.\n\n");
3427 setup_job_control();
3430 if (argv[optind]==NULL) {
3431 opt=parse_file_outer(stdin);
3435 debug_printf("\nrunning script '%s'\n", argv[optind]);
3436 global_argv = argv+optind;
3437 global_argc = argc-optind;
3438 input = xfopen(argv[optind], "r");
3439 opt = parse_file_outer(input);
3441 #ifdef CONFIG_FEATURE_CLEAN_UP
3443 if (cwd && cwd != unknown)
3446 struct variables *cur, *tmp;
3447 for(cur = top_vars; cur; cur = tmp) {
3449 if (!cur->flg_read_only) {
3459 return(opt?opt:last_return_code);
3463 static char *insert_var_value(char *inp)
3465 int res_str_len = 0;
3468 char *p, *p1, *res_str = NULL;
3470 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3473 res_str = xrealloc(res_str, (res_str_len + len));
3474 strncpy((res_str + res_str_len), inp, len);
3478 p = strchr(inp, SPECIAL_VAR_SYMBOL);
3480 if ((p1 = lookup_param(inp))) {
3481 len = res_str_len + strlen(p1);
3482 res_str = xrealloc(res_str, (1 + len));
3483 strcpy((res_str + res_str_len), p1);
3486 *p = SPECIAL_VAR_SYMBOL;
3491 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3492 strcpy((res_str + res_str_len), inp);
3493 while ((p = strchr(res_str, '\n'))) {
3497 return (res_str == NULL) ? inp : res_str;
3500 static char **make_list_in(char **inp, char *name)
3503 int name_len = strlen(name);
3508 /* create list of variable values */
3509 list = xmalloc(sizeof(*list));
3510 for (i = 0; inp[i]; i++) {
3511 p3 = insert_var_value(inp[i]);
3518 if ((p2 = strchr(p1, ' '))) {
3524 /* we use n + 2 in realloc for list,because we add
3525 * new element and then we will add NULL element */
3526 list = xrealloc(list, sizeof(*list) * (n + 2));
3527 list[n] = xmalloc(2 + name_len + len);
3528 strcpy(list[n], name);
3529 strcat(list[n], "=");
3530 strncat(list[n], p1, len);
3531 list[n++][name_len + len + 1] = '\0';
3534 if (p3 != inp[i]) free(p3);
3540 /* Make new string for parser */
3541 static char * make_string(char ** inp)
3548 for (n = 0; inp[n]; n++) {
3549 p = insert_var_value(inp[n]);
3550 str = xrealloc(str, (len + strlen(p)));
3557 len = strlen(str) + 3;
3558 if (p != inp[n]) free(p);
3561 *(str + len) = '\n';
3562 *(str + len + 1) = '\0';
3567 int do_showvar (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
3571 struct variables *cur;
3573 if (argc == 1) { /* Print all env variables */
3574 for (cur = top_vars; cur; cur = cur->next) {
3575 printf ("%s=%s\n", cur->name, cur->value);
3577 puts ("\n ** Abort\n");
3583 for (i = 1; i < argc; ++i) { /* print single env variables */
3584 char *name = argv[i];
3587 for (cur = top_vars; cur; cur = cur->next) {
3588 if(strcmp (cur->name, name) == 0) {
3590 printf ("%s=%s\n", cur->name, cur->value);
3593 puts ("\n ** Abort\n");
3598 printf ("## Error: \"%s\" not defined\n", name);
3606 showvar, CONFIG_SYS_MAXARGS, 1, do_showvar,
3607 "print local hushshell variables",
3608 "\n - print values of all hushshell variables\n"
3609 "showvar name ...\n"
3610 " - print value of hushshell variable 'name'"
3614 /****************************************************************************/