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 */
95 #ifndef CONFIG_SYS_PROMPT_HUSH_PS2
96 #define CONFIG_SYS_PROMPT_HUSH_PS2 "> "
100 #include <ctype.h> /* isalpha, isdigit */
101 #include <unistd.h> /* getpid */
102 #include <stdlib.h> /* getenv, atoi */
103 #include <string.h> /* strchr */
104 #include <stdio.h> /* popen etc. */
105 #include <glob.h> /* glob, of course */
106 #include <stdarg.h> /* va_list */
109 #include <getopt.h> /* should be pretty obvious */
111 #include <sys/stat.h> /* ulimit */
112 #include <sys/types.h>
113 #include <sys/wait.h>
116 /* #include <dmalloc.h> */
122 #define applet_name "hush"
123 #include "standalone.h"
124 #define hush_main main
125 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
129 #define SPECIAL_VAR_SYMBOL 03
130 #define SUBSTED_VAR_SYMBOL 04
132 #define FLAG_EXIT_FROM_LOOP 1
133 #define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
134 #define FLAG_REPARSING (1 << 2) /* >= 2nd pass */
139 DECLARE_GLOBAL_DATA_PTR
;
141 #define EXIT_SUCCESS 0
143 #define syntax() syntax_err()
144 #define xstrdup strdup
145 #define error_msg printf
149 REDIRECT_OVERWRITE
= 2,
155 /* The descrip member of this structure is only used to make debugging
157 struct {int mode
; int default_fd
; char *descrip
;} redir_table
[] = {
159 { O_RDONLY
, 0, "<" },
160 { O_CREAT
|O_TRUNC
|O_WRONLY
, 1, ">" },
161 { O_CREAT
|O_APPEND
|O_WRONLY
, 1, ">>" },
162 { O_RDONLY
, -1, "<<" },
174 /* might eventually control execution */
191 #define FLAG_END (1<<RES_NONE)
192 #define FLAG_IF (1<<RES_IF)
193 #define FLAG_THEN (1<<RES_THEN)
194 #define FLAG_ELIF (1<<RES_ELIF)
195 #define FLAG_ELSE (1<<RES_ELSE)
196 #define FLAG_FI (1<<RES_FI)
197 #define FLAG_FOR (1<<RES_FOR)
198 #define FLAG_WHILE (1<<RES_WHILE)
199 #define FLAG_UNTIL (1<<RES_UNTIL)
200 #define FLAG_DO (1<<RES_DO)
201 #define FLAG_DONE (1<<RES_DONE)
202 #define FLAG_IN (1<<RES_IN)
203 #define FLAG_START (1<<RES_XXXX)
205 /* This holds pointers to the various results of parsing */
207 struct child_prog
*child
;
208 struct pipe
*list_head
;
211 struct redir_struct
*pending_redirect
;
214 int old_flag
; /* for figuring out valid reserved words */
215 struct p_context
*stack
;
216 int type
; /* define type of parser : ";$" common or special symbol */
217 /* How about quoting status? */
221 struct redir_struct
{
222 redir_type type
; /* type of redirection */
223 int fd
; /* file descriptor being redirected */
224 int dup
; /* -1, or file descriptor being duplicated */
225 struct redir_struct
*next
; /* pointer to the next redirect in the list */
226 glob_t word
; /* *word.gl_pathv is the filename */
232 pid_t pid
; /* 0 if exited */
234 char **argv
; /* program name and arguments */
236 int argc
; /* number of program arguments */
238 struct pipe
*group
; /* if non-NULL, first in group or subshell */
240 int subshell
; /* flag, non-zero if group must be forked */
241 struct redir_struct
*redirects
; /* I/O redirections */
242 glob_t glob_result
; /* result of parameter globbing */
243 int is_stopped
; /* is the program currently running? */
244 struct pipe
*family
; /* pointer back to the child's parent pipe */
246 int sp
; /* number of SPECIAL_VAR_SYMBOL */
252 int jobid
; /* job number */
254 int num_progs
; /* total number of programs in job */
256 int running_progs
; /* number of programs running */
257 char *text
; /* name of job */
258 char *cmdbuf
; /* buffer various argv's point into */
259 pid_t pgrp
; /* process group ID for the job */
261 struct child_prog
*progs
; /* array of commands in pipe */
262 struct pipe
*next
; /* to track background commands */
264 int stopped_progs
; /* number of programs alive, but stopped */
265 int job_context
; /* bitmask defining current context */
267 pipe_style followup
; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
268 reserved_style r_mode
; /* supports if, for, while, until */
274 struct close_me
*next
;
283 struct variables
*next
;
286 /* globals, connect us to the outside world
287 * the first three support $?, $#, and $1 */
290 unsigned int global_argc
;
292 static unsigned int last_return_code
;
294 extern char **environ
; /* This is in <unistd.h>, but protected with __USE_GNU */
297 /* "globals" within this file */
299 static char map
[256];
301 static int fake_mode
;
302 static int interactive
;
303 static struct close_me
*close_me_head
;
304 static const char *cwd
;
305 static struct pipe
*job_list
;
306 static unsigned int last_bg_pid
;
307 static unsigned int last_jobid
;
308 static unsigned int shell_terminal
;
311 struct variables shell_ver
= { "HUSH_VERSION", "0.01", 1, 1, 0 };
312 struct variables
*top_vars
= &shell_ver
;
314 static int flag_repeat
= 0;
315 static int do_repeat
= 0;
316 static struct variables
*top_vars
= NULL
;
317 #endif /*__U_BOOT__ */
319 #define B_CHUNK (100)
329 #define NULL_O_STRING {NULL,0,0,0,0}
330 /* used for initialization:
331 o_string foo = NULL_O_STRING; */
333 /* I can almost use ordinary FILE *. Is open_memstream() universally
334 * available? Where is it documented? */
345 int (*get
) (struct in_str
*);
346 int (*peek
) (struct in_str
*);
348 #define b_getch(input) ((input)->get(input))
349 #define b_peek(input) ((input)->peek(input))
352 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
354 struct built_in_command
{
355 char *cmd
; /* name */
356 char *descr
; /* description */
357 int (*function
) (struct child_prog
*); /* function ptr */
361 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
366 /* This should be in utility.c */
369 static void debug_printf(const char *format
, ...)
372 va_start(args
, format
);
373 vfprintf(stderr
, format
, args
);
377 #define debug_printf(fmt,args...) printf (fmt ,##args)
380 static inline void debug_printf(const char *format
, ...) { }
382 #define final_printf debug_printf
385 static void syntax_err(void) {
386 printf("syntax error\n");
389 static void __syntax(char *file
, int line
) {
390 error_msg("syntax error %s:%d", file
, line
);
392 #define syntax() __syntax(__FILE__, __LINE__)
396 static void *xmalloc(size_t size
);
397 static void *xrealloc(void *ptr
, size_t size
);
399 /* Index of subroutines: */
400 /* function prototypes for builtins */
401 static int builtin_cd(struct child_prog
*child
);
402 static int builtin_env(struct child_prog
*child
);
403 static int builtin_eval(struct child_prog
*child
);
404 static int builtin_exec(struct child_prog
*child
);
405 static int builtin_exit(struct child_prog
*child
);
406 static int builtin_export(struct child_prog
*child
);
407 static int builtin_fg_bg(struct child_prog
*child
);
408 static int builtin_help(struct child_prog
*child
);
409 static int builtin_jobs(struct child_prog
*child
);
410 static int builtin_pwd(struct child_prog
*child
);
411 static int builtin_read(struct child_prog
*child
);
412 static int builtin_set(struct child_prog
*child
);
413 static int builtin_shift(struct child_prog
*child
);
414 static int builtin_source(struct child_prog
*child
);
415 static int builtin_umask(struct child_prog
*child
);
416 static int builtin_unset(struct child_prog
*child
);
417 static int builtin_not_written(struct child_prog
*child
);
419 /* o_string manipulation: */
420 static int b_check_space(o_string
*o
, int len
);
421 static int b_addchr(o_string
*o
, int ch
);
422 static void b_reset(o_string
*o
);
423 static int b_addqchr(o_string
*o
, int ch
, int quote
);
425 static int b_adduint(o_string
*o
, unsigned int i
);
427 /* in_str manipulations: */
428 static int static_get(struct in_str
*i
);
429 static int static_peek(struct in_str
*i
);
430 static int file_get(struct in_str
*i
);
431 static int file_peek(struct in_str
*i
);
433 static void setup_file_in_str(struct in_str
*i
, FILE *f
);
435 static void setup_file_in_str(struct in_str
*i
);
437 static void setup_string_in_str(struct in_str
*i
, const char *s
);
439 /* close_me manipulations: */
440 static void mark_open(int fd
);
441 static void mark_closed(int fd
);
442 static void close_all(void);
444 /* "run" the final data structures: */
445 static char *indenter(int i
);
446 static int free_pipe_list(struct pipe
*head
, int indent
);
447 static int free_pipe(struct pipe
*pi
, int indent
);
448 /* really run the final data structures: */
450 static int setup_redirects(struct child_prog
*prog
, int squirrel
[]);
452 static int run_list_real(struct pipe
*pi
);
454 static void pseudo_exec(struct child_prog
*child
) __attribute__ ((noreturn
));
456 static int run_pipe_real(struct pipe
*pi
);
457 /* extended glob support: */
459 static int globhack(const char *src
, int flags
, glob_t
*pglob
);
460 static int glob_needed(const char *s
);
461 static int xglob(o_string
*dest
, int flags
, glob_t
*pglob
);
463 /* variable assignment: */
464 static int is_assignment(const char *s
);
465 /* data structure manipulation: */
467 static int setup_redirect(struct p_context
*ctx
, int fd
, redir_type style
, struct in_str
*input
);
469 static void initialize_context(struct p_context
*ctx
);
470 static int done_word(o_string
*dest
, struct p_context
*ctx
);
471 static int done_command(struct p_context
*ctx
);
472 static int done_pipe(struct p_context
*ctx
, pipe_style type
);
473 /* primary string parsing: */
475 static int redirect_dup_num(struct in_str
*input
);
476 static int redirect_opt_num(o_string
*o
);
477 static int process_command_subs(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
, int subst_end
);
478 static int parse_group(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
, int ch
);
480 static char *lookup_param(char *src
);
481 static char *make_string(char **inp
);
482 static int handle_dollar(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
);
484 static int parse_string(o_string
*dest
, struct p_context
*ctx
, const char *src
);
486 static int parse_stream(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input0
, int end_trigger
);
488 static int parse_stream_outer(struct in_str
*inp
, int flag
);
490 static int parse_string_outer(const char *s
, int flag
);
491 static int parse_file_outer(FILE *f
);
494 /* job management: */
495 static int checkjobs(struct pipe
* fg_pipe
);
496 static void insert_bg_job(struct pipe
*pi
);
497 static void remove_bg_job(struct pipe
*pi
);
499 /* local variable support */
500 static char **make_list_in(char **inp
, char *name
);
501 static char *insert_var_value(char *inp
);
502 static char *insert_var_value_sub(char *inp
, int tag_subst
);
505 /* Table of built-in functions. They can be forked or not, depending on
506 * context: within pipes, they fork. As simple commands, they do not.
507 * When used in non-forking context, they can change global variables
508 * in the parent shell process. If forked, of course they can not.
509 * For example, 'unset foo | whatever' will parse and run, but foo will
510 * still be set at the end. */
511 static struct built_in_command bltins
[] = {
512 {"bg", "Resume a job in the background", builtin_fg_bg
},
513 {"break", "Exit for, while or until loop", builtin_not_written
},
514 {"cd", "Change working directory", builtin_cd
},
515 {"continue", "Continue for, while or until loop", builtin_not_written
},
516 {"env", "Print all environment variables", builtin_env
},
517 {"eval", "Construct and run shell command", builtin_eval
},
518 {"exec", "Exec command, replacing this shell with the exec'd process",
520 {"exit", "Exit from shell()", builtin_exit
},
521 {"export", "Set environment variable", builtin_export
},
522 {"fg", "Bring job into the foreground", builtin_fg_bg
},
523 {"jobs", "Lists the active jobs", builtin_jobs
},
524 {"pwd", "Print current directory", builtin_pwd
},
525 {"read", "Input environment variable", builtin_read
},
526 {"return", "Return from a function", builtin_not_written
},
527 {"set", "Set/unset shell local variables", builtin_set
},
528 {"shift", "Shift positional parameters", builtin_shift
},
529 {"trap", "Trap signals", builtin_not_written
},
530 {"ulimit","Controls resource limits", builtin_not_written
},
531 {"umask","Sets file creation mask", builtin_umask
},
532 {"unset", "Unset environment variable", builtin_unset
},
533 {".", "Source-in and run commands in a file", builtin_source
},
534 {"help", "List shell built-in commands", builtin_help
},
538 static const char *set_cwd(void)
541 cwd
= NULL
; /* xgetcwd(arg) called free(arg) */
542 cwd
= xgetcwd((char *)cwd
);
548 /* built-in 'eval' handler */
549 static int builtin_eval(struct child_prog
*child
)
552 int rcode
= EXIT_SUCCESS
;
554 if (child
->argv
[1]) {
555 str
= make_string(child
->argv
+ 1);
556 parse_string_outer(str
, FLAG_EXIT_FROM_LOOP
|
557 FLAG_PARSE_SEMICOLON
);
559 rcode
= last_return_code
;
564 /* built-in 'cd <path>' handler */
565 static int builtin_cd(struct child_prog
*child
)
568 if (child
->argv
[1] == NULL
)
569 newdir
= getenv("HOME");
571 newdir
= child
->argv
[1];
573 printf("cd: %s: %s\n", newdir
, strerror(errno
));
580 /* built-in 'env' handler */
581 static int builtin_env(struct child_prog
*dummy
)
584 if (e
== NULL
) return EXIT_FAILURE
;
591 /* built-in 'exec' handler */
592 static int builtin_exec(struct child_prog
*child
)
594 if (child
->argv
[1] == NULL
)
595 return EXIT_SUCCESS
; /* Really? */
601 /* built-in 'exit' handler */
602 static int builtin_exit(struct child_prog
*child
)
604 if (child
->argv
[1] == NULL
)
605 exit(last_return_code
);
606 exit (atoi(child
->argv
[1]));
609 /* built-in 'export VAR=value' handler */
610 static int builtin_export(struct child_prog
*child
)
613 char *name
= child
->argv
[1];
616 return (builtin_env(child
));
622 char *value
= strchr(name
, '=');
626 /* They are exporting something without an =VALUE */
628 value
= get_local_var(name
);
630 size_t ln
= strlen(name
);
632 tmp
= realloc(name
, ln
+strlen(value
)+2);
636 sprintf(tmp
+ln
, "=%s", value
);
640 /* bash does not return an error when trying to export
641 * an undefined variable. Do likewise. */
647 perror_msg("export");
649 res
= set_local_var(name
, 1);
656 /* built-in 'fg' and 'bg' handler */
657 static int builtin_fg_bg(struct child_prog
*child
)
660 struct pipe
*pi
=NULL
;
664 /* If they gave us no args, assume they want the last backgrounded task */
665 if (!child
->argv
[1]) {
666 for (pi
= job_list
; pi
; pi
= pi
->next
) {
667 if (pi
->jobid
== last_jobid
) {
672 error_msg("%s: no current job", child
->argv
[0]);
676 if (sscanf(child
->argv
[1], "%%%d", &jobnum
) != 1) {
677 error_msg("%s: bad argument '%s'", child
->argv
[0], child
->argv
[1]);
680 for (pi
= job_list
; pi
; pi
= pi
->next
) {
681 if (pi
->jobid
== jobnum
) {
686 error_msg("%s: %d: no such job", child
->argv
[0], jobnum
);
691 if (*child
->argv
[0] == 'f') {
692 /* Put the job into the foreground. */
693 tcsetpgrp(shell_terminal
, pi
->pgrp
);
696 /* Restart the processes in the job */
697 for (i
= 0; i
< pi
->num_progs
; i
++)
698 pi
->progs
[i
].is_stopped
= 0;
700 if ( (i
=kill(- pi
->pgrp
, SIGCONT
)) < 0) {
704 perror_msg("kill (SIGCONT)");
708 pi
->stopped_progs
= 0;
712 /* built-in 'help' handler */
713 static int builtin_help(struct child_prog
*dummy
)
715 struct built_in_command
*x
;
717 printf("\nBuilt-in commands:\n");
718 printf("-------------------\n");
719 for (x
= bltins
; x
->cmd
; x
++) {
722 printf("%s\t%s\n", x
->cmd
, x
->descr
);
728 /* built-in 'jobs' handler */
729 static int builtin_jobs(struct child_prog
*child
)
734 for (job
= job_list
; job
; job
= job
->next
) {
735 if (job
->running_progs
== job
->stopped_progs
)
736 status_string
= "Stopped";
738 status_string
= "Running";
740 printf(JOB_STATUS_FORMAT
, job
->jobid
, status_string
, job
->text
);
746 /* built-in 'pwd' handler */
747 static int builtin_pwd(struct child_prog
*dummy
)
753 /* built-in 'read VAR' handler */
754 static int builtin_read(struct child_prog
*child
)
758 if (child
->argv
[1]) {
762 string
[0] = 0; /* In case stdin has only EOF */
764 fgets(string
, sizeof(string
), stdin
);
766 var
= malloc(strlen(child
->argv
[1])+strlen(string
)+2);
768 sprintf(var
, "%s=%s", child
->argv
[1], string
);
769 res
= set_local_var(var
, 0);
773 fprintf(stderr
, "read: %m\n");
774 free(var
); /* So not move up to avoid breaking errno */
777 do res
=getchar(); while(res
!='\n' && res
!=EOF
);
782 /* built-in 'set VAR=value' handler */
783 static int builtin_set(struct child_prog
*child
)
785 char *temp
= child
->argv
[1];
789 for(e
= top_vars
; e
; e
=e
->next
)
790 printf("%s=%s\n", e
->name
, e
->value
);
792 set_local_var(temp
, 0);
798 /* Built-in 'shift' handler */
799 static int builtin_shift(struct child_prog
*child
)
802 if (child
->argv
[1]) {
803 n
=atoi(child
->argv
[1]);
805 if (n
>=0 && n
<global_argc
) {
806 /* XXX This probably breaks $0 */
815 /* Built-in '.' handler (read-in and execute commands from file) */
816 static int builtin_source(struct child_prog
*child
)
821 if (child
->argv
[1] == NULL
)
824 /* XXX search through $PATH is missing */
825 input
= fopen(child
->argv
[1], "r");
827 error_msg("Couldn't open file '%s'", child
->argv
[1]);
831 /* Now run the file */
832 /* XXX argv and argc are broken; need to save old global_argv
833 * (pointer only is OK!) on this stack frame,
834 * set global_argv=child->argv+1, recurse, and restore. */
835 mark_open(fileno(input
));
836 status
= parse_file_outer(input
);
837 mark_closed(fileno(input
));
842 static int builtin_umask(struct child_prog
*child
)
845 const char *arg
= child
->argv
[1];
848 new_umask
=strtoul(arg
, &end
, 8);
849 if (*end
!='\0' || end
== arg
) {
853 printf("%.3o\n", (unsigned int) (new_umask
=umask(0)));
859 /* built-in 'unset VAR' handler */
860 static int builtin_unset(struct child_prog
*child
)
862 /* bash returned already true */
863 unset_local_var(child
->argv
[1]);
867 static int builtin_not_written(struct child_prog
*child
)
869 printf("builtin_%s not written\n",child
->argv
[0]);
874 static int b_check_space(o_string
*o
, int len
)
876 /* It would be easy to drop a more restrictive policy
877 * in here, such as setting a maximum string length */
878 if (o
->length
+ len
> o
->maxlen
) {
879 char *old_data
= o
->data
;
880 /* assert (data == NULL || o->maxlen != 0); */
881 o
->maxlen
+= max(2*len
, B_CHUNK
);
882 o
->data
= realloc(o
->data
, 1 + o
->maxlen
);
883 if (o
->data
== NULL
) {
887 return o
->data
== NULL
;
890 static int b_addchr(o_string
*o
, int ch
)
892 debug_printf("b_addchr: %c %d %p\n", ch
, o
->length
, o
);
893 if (b_check_space(o
, 1)) return B_NOSPAC
;
894 o
->data
[o
->length
] = ch
;
896 o
->data
[o
->length
] = '\0';
900 static void b_reset(o_string
*o
)
904 if (o
->data
!= NULL
) *o
->data
= '\0';
907 static void b_free(o_string
*o
)
915 /* My analysis of quoting semantics tells me that state information
916 * is associated with a destination, not a source.
918 static int b_addqchr(o_string
*o
, int ch
, int quote
)
920 if (quote
&& strchr("*?[\\",ch
)) {
922 rc
= b_addchr(o
, '\\');
925 return b_addchr(o
, ch
);
929 static int b_adduint(o_string
*o
, unsigned int i
)
932 char *p
= simple_itoa(i
);
933 /* no escape checking necessary */
934 do r
=b_addchr(o
, *p
++); while (r
==0 && *p
);
939 static int static_get(struct in_str
*i
)
942 if (ch
=='\0') return EOF
;
946 static int static_peek(struct in_str
*i
)
952 static inline void cmdedit_set_initial_prompt(void)
954 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
963 static inline void setup_prompt_string(int promptmode
, char **prompt_str
)
965 debug_printf("setup_prompt_string %d ",promptmode
);
966 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
967 /* Set up the prompt */
968 if (promptmode
== 1) {
970 PS1
=xmalloc(strlen(cwd
)+4);
971 sprintf(PS1
, "%s %s", cwd
, ( geteuid() != 0 ) ? "$ ":"# ");
977 *prompt_str
= (promptmode
==1)? PS1
: PS2
;
979 debug_printf("result %s\n",*prompt_str
);
983 static void get_user_input(struct in_str
*i
)
987 static char the_command
[BUFSIZ
];
989 setup_prompt_string(i
->promptmode
, &prompt_str
);
990 #ifdef CONFIG_FEATURE_COMMAND_EDITING
992 ** enable command line editing only while a command line
993 ** is actually being read; otherwise, we'll end up bequeathing
994 ** atexit() handlers and other unwanted stuff to our
995 ** child processes (rob@sysgo.de)
997 cmdedit_read_input(prompt_str
, the_command
);
999 fputs(prompt_str
, stdout
);
1001 the_command
[0]=fgetc(i
->file
);
1002 the_command
[1]='\0';
1008 static char the_command
[CONFIG_SYS_CBSIZE
];
1010 #ifdef CONFIG_BOOT_RETRY_TIME
1011 # ifndef CONFIG_RESET_TO_RETRY
1012 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1014 reset_cmd_timeout();
1017 if (i
->promptmode
== 1) {
1018 n
= readline(CONFIG_SYS_PROMPT
);
1020 n
= readline(CONFIG_SYS_PROMPT_HUSH_PS2
);
1022 #ifdef CONFIG_BOOT_RETRY_TIME
1024 puts("\nTimeout waiting for command\n");
1025 # ifdef CONFIG_RESET_TO_RETRY
1026 do_reset(NULL
, 0, 0, NULL
);
1028 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1036 n
= strlen(console_buffer
);
1037 console_buffer
[n
] = '\n';
1038 console_buffer
[n
+1]= '\0';
1039 if (had_ctrlc()) flag_repeat
= 0;
1042 if (i
->promptmode
== 1) {
1043 if (console_buffer
[0] == '\n'&& flag_repeat
== 0) {
1044 strcpy(the_command
,console_buffer
);
1047 if (console_buffer
[0] != '\n') {
1048 strcpy(the_command
,console_buffer
);
1058 if (console_buffer
[0] != '\n') {
1059 if (strlen(the_command
) + strlen(console_buffer
)
1060 < CONFIG_SYS_CBSIZE
) {
1061 n
= strlen(the_command
);
1062 the_command
[n
-1] = ' ';
1063 strcpy(&the_command
[n
],console_buffer
);
1066 the_command
[0] = '\n';
1067 the_command
[1] = '\0';
1071 if (i
->__promptme
== 0) {
1072 the_command
[0] = '\n';
1073 the_command
[1] = '\0';
1075 i
->p
= console_buffer
;
1080 /* This is the magic location that prints prompts
1081 * and gets data back from the user */
1082 static int file_get(struct in_str
*i
)
1087 /* If there is data waiting, eat it up */
1088 if (i
->p
&& *i
->p
) {
1091 /* need to double check i->file because we might be doing something
1092 * more complicated by now, like sourcing or substituting. */
1094 if (i
->__promptme
&& interactive
&& i
->file
== stdin
) {
1095 while(! i
->p
|| (interactive
&& strlen(i
->p
)==0) ) {
1097 while(! i
->p
|| strlen(i
->p
)==0 ) {
1105 if (i
->p
&& *i
->p
) {
1110 ch
= fgetc(i
->file
);
1114 debug_printf("b_getch: got a %d\n", ch
);
1117 if (ch
== '\n') i
->__promptme
=1;
1122 /* All the callers guarantee this routine will never be
1123 * used right after a newline, so prompting is not needed.
1125 static int file_peek(struct in_str
*i
)
1128 if (i
->p
&& *i
->p
) {
1133 i
->peek_buf
[0] = fgetc(i
->file
);
1134 i
->peek_buf
[1] = '\0';
1136 debug_printf("b_peek: got a %d\n", *i
->p
);
1143 static void setup_file_in_str(struct in_str
*i
, FILE *f
)
1145 static void setup_file_in_str(struct in_str
*i
)
1148 i
->peek
= file_peek
;
1158 static void setup_string_in_str(struct in_str
*i
, const char *s
)
1160 i
->peek
= static_peek
;
1161 i
->get
= static_get
;
1168 static void mark_open(int fd
)
1170 struct close_me
*new = xmalloc(sizeof(struct close_me
));
1172 new->next
= close_me_head
;
1173 close_me_head
= new;
1176 static void mark_closed(int fd
)
1178 struct close_me
*tmp
;
1179 if (close_me_head
== NULL
|| close_me_head
->fd
!= fd
)
1180 error_msg_and_die("corrupt close_me");
1181 tmp
= close_me_head
;
1182 close_me_head
= close_me_head
->next
;
1186 static void close_all(void)
1189 for (c
=close_me_head
; c
; c
=c
->next
) {
1192 close_me_head
= NULL
;
1195 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1196 * and stderr if they are redirected. */
1197 static int setup_redirects(struct child_prog
*prog
, int squirrel
[])
1200 struct redir_struct
*redir
;
1202 for (redir
=prog
->redirects
; redir
; redir
=redir
->next
) {
1203 if (redir
->dup
== -1 && redir
->word
.gl_pathv
== NULL
) {
1204 /* something went wrong in the parse. Pretend it didn't happen */
1207 if (redir
->dup
== -1) {
1208 mode
=redir_table
[redir
->type
].mode
;
1209 openfd
= open(redir
->word
.gl_pathv
[0], mode
, 0666);
1211 /* this could get lost if stderr has been redirected, but
1212 bash and ash both lose it as well (though zsh doesn't!) */
1213 perror_msg("error opening %s", redir
->word
.gl_pathv
[0]);
1217 openfd
= redir
->dup
;
1220 if (openfd
!= redir
->fd
) {
1221 if (squirrel
&& redir
->fd
< 3) {
1222 squirrel
[redir
->fd
] = dup(redir
->fd
);
1227 dup2(openfd
, redir
->fd
);
1228 if (redir
->dup
== -1)
1236 static void restore_redirects(int squirrel
[])
1239 for (i
=0; i
<3; i
++) {
1242 /* No error checking. I sure wouldn't know what
1243 * to do with an error if I found one! */
1251 /* XXX no exit() here. If you don't exec, use _exit instead.
1252 * The at_exit handlers apparently confuse the calling process,
1253 * in particular stdin handling. Not sure why? */
1254 static void pseudo_exec(struct child_prog
*child
)
1258 struct built_in_command
*x
;
1260 for (i
=0; is_assignment(child
->argv
[i
]); i
++) {
1261 debug_printf("pid %d environment modification: %s\n",getpid(),child
->argv
[i
]);
1262 p
= insert_var_value(child
->argv
[i
]);
1264 if (p
!= child
->argv
[i
]) free(p
);
1266 child
->argv
+=i
; /* XXX this hack isn't so horrible, since we are about
1267 to exit, and therefore don't need to keep data
1268 structures consistent for free() use. */
1269 /* If a variable is assigned in a forest, and nobody listens,
1270 * was it ever really set?
1272 if (child
->argv
[0] == NULL
) {
1273 _exit(EXIT_SUCCESS
);
1277 * Check if the command matches any of the builtins.
1278 * Depending on context, this might be redundant. But it's
1279 * easier to waste a few CPU cycles than it is to figure out
1280 * if this is one of those cases.
1282 for (x
= bltins
; x
->cmd
; x
++) {
1283 if (strcmp(child
->argv
[0], x
->cmd
) == 0 ) {
1284 debug_printf("builtin exec %s\n", child
->argv
[0]);
1285 rcode
= x
->function(child
);
1291 /* Check if the command matches any busybox internal commands
1293 * FIXME: This feature is not 100% safe, since
1294 * BusyBox is not fully reentrant, so we have no guarantee the things
1295 * from the .bss are still zeroed, or that things from .data are still
1296 * at their defaults. We could exec ourself from /proc/self/exe, but I
1297 * really dislike relying on /proc for things. We could exec ourself
1298 * from global_argv[0], but if we are in a chroot, we may not be able
1299 * to find ourself... */
1300 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1303 char** argv_l
=child
->argv
;
1304 char *name
= child
->argv
[0];
1306 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1307 /* Following discussions from November 2000 on the busybox mailing
1308 * list, the default configuration, (without
1309 * get_last_path_component()) lets the user force use of an
1310 * external command by specifying the full (with slashes) filename.
1311 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1312 * _aways_ override external commands, so if you want to run
1313 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1314 * filesystem and is _not_ busybox. Some systems may want this,
1316 name
= get_last_path_component(name
);
1318 /* Count argc for use in a second... */
1319 for(argc_l
=0;*argv_l
!=NULL
; argv_l
++, argc_l
++);
1321 debug_printf("running applet %s\n", name
);
1322 run_applet_by_name(name
, argc_l
, child
->argv
);
1325 debug_printf("exec of %s\n",child
->argv
[0]);
1326 execvp(child
->argv
[0],child
->argv
);
1327 perror_msg("couldn't exec: %s",child
->argv
[0]);
1329 } else if (child
->group
) {
1330 debug_printf("runtime nesting to group\n");
1331 interactive
=0; /* crucial!!!! */
1332 rcode
= run_list_real(child
->group
);
1333 /* OK to leak memory by not calling free_pipe_list,
1334 * since this process is about to exit */
1337 /* Can happen. See what bash does with ">foo" by itself. */
1338 debug_printf("trying to pseudo_exec null command\n");
1339 _exit(EXIT_SUCCESS
);
1343 static void insert_bg_job(struct pipe
*pi
)
1345 struct pipe
*thejob
;
1347 /* Linear search for the ID of the job to use */
1349 for (thejob
= job_list
; thejob
; thejob
= thejob
->next
)
1350 if (thejob
->jobid
>= pi
->jobid
)
1351 pi
->jobid
= thejob
->jobid
+ 1;
1353 /* add thejob to the list of running jobs */
1355 thejob
= job_list
= xmalloc(sizeof(*thejob
));
1357 for (thejob
= job_list
; thejob
->next
; thejob
= thejob
->next
) /* nothing */;
1358 thejob
->next
= xmalloc(sizeof(*thejob
));
1359 thejob
= thejob
->next
;
1362 /* physically copy the struct job */
1363 memcpy(thejob
, pi
, sizeof(struct pipe
));
1364 thejob
->next
= NULL
;
1365 thejob
->running_progs
= thejob
->num_progs
;
1366 thejob
->stopped_progs
= 0;
1367 thejob
->text
= xmalloc(BUFSIZ
); /* cmdedit buffer size */
1369 /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1371 char *bar
=thejob
->text
;
1372 char **foo
=pi
->progs
[0].argv
;
1373 while(foo
&& *foo
) {
1374 bar
+= sprintf(bar
, "%s ", *foo
++);
1378 /* we don't wait for background thejobs to return -- append it
1379 to the list of backgrounded thejobs and leave it alone */
1380 printf("[%d] %d\n", thejob
->jobid
, thejob
->progs
[0].pid
);
1381 last_bg_pid
= thejob
->progs
[0].pid
;
1382 last_jobid
= thejob
->jobid
;
1385 /* remove a backgrounded job */
1386 static void remove_bg_job(struct pipe
*pi
)
1388 struct pipe
*prev_pipe
;
1390 if (pi
== job_list
) {
1391 job_list
= pi
->next
;
1393 prev_pipe
= job_list
;
1394 while (prev_pipe
->next
!= pi
)
1395 prev_pipe
= prev_pipe
->next
;
1396 prev_pipe
->next
= pi
->next
;
1399 last_jobid
= job_list
->jobid
;
1403 pi
->stopped_progs
= 0;
1408 /* Checks to see if any processes have exited -- if they
1409 have, figure out why and see if a job has completed */
1410 static int checkjobs(struct pipe
* fg_pipe
)
1418 attributes
= WUNTRACED
;
1419 if (fg_pipe
==NULL
) {
1420 attributes
|= WNOHANG
;
1423 while ((childpid
= waitpid(-1, &status
, attributes
)) > 0) {
1426 for (i
=0; i
< fg_pipe
->num_progs
; i
++) {
1427 if (fg_pipe
->progs
[i
].pid
== childpid
) {
1428 if (i
==fg_pipe
->num_progs
-1)
1429 rcode
=WEXITSTATUS(status
);
1430 (fg_pipe
->num_progs
)--;
1436 for (pi
= job_list
; pi
; pi
= pi
->next
) {
1438 while (prognum
< pi
->num_progs
&& pi
->progs
[prognum
].pid
!= childpid
) {
1441 if (prognum
< pi
->num_progs
)
1446 debug_printf("checkjobs: pid %d was not in our list!\n", childpid
);
1450 if (WIFEXITED(status
) || WIFSIGNALED(status
)) {
1452 pi
->running_progs
--;
1453 pi
->progs
[prognum
].pid
= 0;
1455 if (!pi
->running_progs
) {
1456 printf(JOB_STATUS_FORMAT
, pi
->jobid
, "Done", pi
->text
);
1461 pi
->stopped_progs
++;
1462 pi
->progs
[prognum
].is_stopped
= 1;
1465 /* Printing this stuff is a pain, since it tends to
1466 * overwrite the prompt an inconveinient moments. So
1468 if (pi
->stopped_progs
== pi
->num_progs
) {
1469 printf("\n"JOB_STATUS_FORMAT
, pi
->jobid
, "Stopped", pi
->text
);
1475 if (childpid
== -1 && errno
!= ECHILD
)
1476 perror_msg("waitpid");
1478 /* move the shell to the foreground */
1479 /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1480 /* perror_msg("tcsetpgrp-2"); */
1484 /* Figure out our controlling tty, checking in order stderr,
1485 * stdin, and stdout. If check_pgrp is set, also check that
1486 * we belong to the foreground process group associated with
1487 * that tty. The value of shell_terminal is needed in order to call
1488 * tcsetpgrp(shell_terminal, ...); */
1489 void controlling_tty(int check_pgrp
)
1493 if ((curpgrp
= tcgetpgrp(shell_terminal
= 2)) < 0
1494 && (curpgrp
= tcgetpgrp(shell_terminal
= 0)) < 0
1495 && (curpgrp
= tcgetpgrp(shell_terminal
= 1)) < 0)
1496 goto shell_terminal_error
;
1498 if (check_pgrp
&& curpgrp
!= getpgid(0))
1499 goto shell_terminal_error
;
1503 shell_terminal_error
:
1504 shell_terminal
= -1;
1509 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1510 * to finish. See checkjobs().
1512 * return code is normally -1, when the caller has to wait for children
1513 * to finish to determine the exit status of the pipe. If the pipe
1514 * is a simple builtin command, however, the action is done by the
1515 * time run_pipe_real returns, and the exit code is provided as the
1518 * The input of the pipe is always stdin, the output is always
1519 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1520 * because it tries to avoid running the command substitution in
1521 * subshell, when that is in fact necessary. The subshell process
1522 * now has its stdout directed to the input of the appropriate pipe,
1523 * so this routine is noticeably simpler.
1525 static int run_pipe_real(struct pipe
*pi
)
1529 int nextin
, nextout
;
1530 int pipefds
[2]; /* pipefds[0] is for reading */
1531 struct child_prog
*child
;
1532 struct built_in_command
*x
;
1535 /* Avoid longjmp clobbering */
1543 int flag
= do_repeat
? CMD_FLAG_REPEAT
: 0;
1544 struct child_prog
*child
;
1547 /* Avoid longjmp clobbering */
1552 #endif /* __U_BOOT__ */
1559 /* Check if this is a simple builtin (not part of a pipe).
1560 * Builtins within pipes have to fork anyway, and are handled in
1561 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1563 if (pi
->num_progs
== 1) child
= & (pi
->progs
[0]);
1565 if (pi
->num_progs
== 1 && child
->group
&& child
->subshell
== 0) {
1566 int squirrel
[] = {-1, -1, -1};
1568 debug_printf("non-subshell grouping\n");
1569 setup_redirects(child
, squirrel
);
1570 /* XXX could we merge code with following builtin case,
1571 * by creating a pseudo builtin that calls run_list_real? */
1572 rcode
= run_list_real(child
->group
);
1573 restore_redirects(squirrel
);
1575 if (pi
->num_progs
== 1 && child
->group
) {
1577 debug_printf("non-subshell grouping\n");
1578 rcode
= run_list_real(child
->group
);
1581 } else if (pi
->num_progs
== 1 && pi
->progs
[0].argv
!= NULL
) {
1582 for (i
=0; is_assignment(child
->argv
[i
]); i
++) { /* nothing */ }
1583 if (i
!=0 && child
->argv
[i
]==NULL
) {
1584 /* assignments, but no command: set the local environment */
1585 for (i
=0; child
->argv
[i
]!=NULL
; i
++) {
1587 /* Ok, this case is tricky. We have to decide if this is a
1588 * local variable, or an already exported variable. If it is
1589 * already exported, we have to export the new value. If it is
1590 * not exported, we need only set this as a local variable.
1591 * This junk is all to decide whether or not to export this
1595 name
= xstrdup(child
->argv
[i
]);
1596 debug_printf("Local environment set: %s\n", name
);
1597 value
= strchr(name
, '=');
1601 if ( get_local_var(name
)) {
1606 p
= insert_var_value(child
->argv
[i
]);
1607 set_local_var(p
, export_me
);
1608 if (p
!= child
->argv
[i
]) free(p
);
1610 return EXIT_SUCCESS
; /* don't worry about errors in set_local_var() yet */
1612 for (i
= 0; is_assignment(child
->argv
[i
]); i
++) {
1613 p
= insert_var_value(child
->argv
[i
]);
1617 set_local_var(p
, 0);
1619 if (p
!= child
->argv
[i
]) {
1627 str
= make_string((child
->argv
+ i
));
1628 parse_string_outer(str
, FLAG_EXIT_FROM_LOOP
| FLAG_REPARSING
);
1630 return last_return_code
;
1633 for (x
= bltins
; x
->cmd
; x
++) {
1634 if (strcmp(child
->argv
[i
], x
->cmd
) == 0 ) {
1635 int squirrel
[] = {-1, -1, -1};
1637 if (x
->function
== builtin_exec
&& child
->argv
[i
+1]==NULL
) {
1638 debug_printf("magic exec\n");
1639 setup_redirects(child
,NULL
);
1640 return EXIT_SUCCESS
;
1642 debug_printf("builtin inline %s\n", child
->argv
[0]);
1643 /* XXX setup_redirects acts on file descriptors, not FILEs.
1644 * This is perfect for work that comes after exec().
1645 * Is it really safe for inline use? Experimentally,
1646 * things seem to work with glibc. */
1647 setup_redirects(child
, squirrel
);
1649 child
->argv
+= i
; /* XXX horrible hack */
1650 rcode
= x
->function(child
);
1651 /* XXX restore hack so free() can work right */
1653 restore_redirects(squirrel
);
1658 /* check ";", because ,example , argv consist from
1659 * "help;flinfo" must not execute
1661 if (strchr(child
->argv
[i
], ';')) {
1662 printf("Unknown command '%s' - try 'help' or use "
1663 "'run' command\n", child
->argv
[i
]);
1666 /* Process the command */
1667 return cmd_process(flag
, child
->argc
, child
->argv
,
1668 &flag_repeat
, NULL
);
1673 for (i
= 0; i
< pi
->num_progs
; i
++) {
1674 child
= & (pi
->progs
[i
]);
1676 /* pipes are inserted between pairs of commands */
1677 if ((i
+ 1) < pi
->num_progs
) {
1678 if (pipe(pipefds
)<0) perror_msg_and_die("pipe");
1679 nextout
= pipefds
[1];
1685 /* XXX test for failed fork()? */
1686 if (!(child
->pid
= fork())) {
1687 /* Set the handling for job control signals back to the default. */
1688 signal(SIGINT
, SIG_DFL
);
1689 signal(SIGQUIT
, SIG_DFL
);
1690 signal(SIGTERM
, SIG_DFL
);
1691 signal(SIGTSTP
, SIG_DFL
);
1692 signal(SIGTTIN
, SIG_DFL
);
1693 signal(SIGTTOU
, SIG_DFL
);
1694 signal(SIGCHLD
, SIG_DFL
);
1706 if (pipefds
[0]!=-1) {
1707 close(pipefds
[0]); /* opposite end of our output pipe */
1710 /* Like bash, explicit redirects override pipes,
1711 * and the pipe fd is available for dup'ing. */
1712 setup_redirects(child
,NULL
);
1714 if (interactive
&& pi
->followup
!=PIPE_BG
) {
1715 /* If we (the child) win the race, put ourselves in the process
1716 * group whose leader is the first process in this pipe. */
1718 pi
->pgrp
= getpid();
1720 if (setpgid(0, pi
->pgrp
) == 0) {
1721 tcsetpgrp(2, pi
->pgrp
);
1729 /* put our child in the process group whose leader is the
1730 first process in this pipe */
1732 pi
->pgrp
= child
->pid
;
1734 /* Don't check for errors. The child may be dead already,
1735 * in which case setpgid returns error code EACCES. */
1736 setpgid(child
->pid
, pi
->pgrp
);
1743 /* If there isn't another process, nextin is garbage
1744 but it doesn't matter */
1745 nextin
= pipefds
[0];
1751 static int run_list_real(struct pipe
*pi
)
1753 char *save_name
= NULL
;
1755 char **save_list
= NULL
;
1761 int rcode
=0, flag_skip
=1;
1762 int flag_restore
= 0;
1763 int if_code
=0, next_if_code
=0; /* need double-buffer to handle elif */
1764 reserved_style rmode
, skip_more_in_this_rmode
=RES_XXXX
;
1765 /* check syntax for "for" */
1766 for (rpipe
= pi
; rpipe
; rpipe
= rpipe
->next
) {
1767 if ((rpipe
->r_mode
== RES_IN
||
1768 rpipe
->r_mode
== RES_FOR
) &&
1769 (rpipe
->next
== NULL
)) {
1776 if ((rpipe
->r_mode
== RES_IN
&&
1777 (rpipe
->next
->r_mode
== RES_IN
&&
1778 rpipe
->next
->progs
->argv
!= NULL
))||
1779 (rpipe
->r_mode
== RES_FOR
&&
1780 rpipe
->next
->r_mode
!= RES_IN
)) {
1788 for (; pi
; pi
= (flag_restore
!= 0) ? rpipe
: pi
->next
) {
1789 if (pi
->r_mode
== RES_WHILE
|| pi
->r_mode
== RES_UNTIL
||
1790 pi
->r_mode
== RES_FOR
) {
1794 if ((had_ctrlc())) {
1805 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
);
1806 if (rmode
== skip_more_in_this_rmode
&& flag_skip
) {
1807 if (pi
->followup
== PIPE_SEQ
) flag_skip
=0;
1811 skip_more_in_this_rmode
= RES_XXXX
;
1812 if (rmode
== RES_THEN
|| rmode
== RES_ELSE
) if_code
= next_if_code
;
1813 if (rmode
== RES_THEN
&& if_code
) continue;
1814 if (rmode
== RES_ELSE
&& !if_code
) continue;
1815 if (rmode
== RES_ELIF
&& !if_code
) break;
1816 if (rmode
== RES_FOR
&& pi
->num_progs
) {
1818 /* if no variable values after "in" we skip "for" */
1819 if (!pi
->next
->progs
->argv
) continue;
1820 /* create list of variable values */
1821 list
= make_list_in(pi
->next
->progs
->argv
,
1822 pi
->progs
->argv
[0]);
1824 save_name
= pi
->progs
->argv
[0];
1825 pi
->progs
->argv
[0] = NULL
;
1829 free(pi
->progs
->argv
[0]);
1833 pi
->progs
->argv
[0] = save_name
;
1835 pi
->progs
->glob_result
.gl_pathv
[0] =
1840 /* insert new value from list for variable */
1841 if (pi
->progs
->argv
[0])
1842 free(pi
->progs
->argv
[0]);
1843 pi
->progs
->argv
[0] = *list
++;
1845 pi
->progs
->glob_result
.gl_pathv
[0] =
1850 if (rmode
== RES_IN
) continue;
1851 if (rmode
== RES_DO
) {
1852 if (!flag_rep
) continue;
1854 if ((rmode
== RES_DONE
)) {
1861 if (pi
->num_progs
== 0) continue;
1863 save_num_progs
= pi
->num_progs
; /* save number of programs */
1865 rcode
= run_pipe_real(pi
);
1866 debug_printf("run_pipe_real returned %d\n",rcode
);
1869 /* We only ran a builtin: rcode was set by the return value
1870 * of run_pipe_real(), and we don't need to wait for anything. */
1871 } else if (pi
->followup
==PIPE_BG
) {
1872 /* XXX check bash's behavior with nontrivial pipes */
1873 /* XXX compute jobid */
1874 /* XXX what does bash do with attempts to background builtins? */
1876 rcode
= EXIT_SUCCESS
;
1879 /* move the new process group into the foreground */
1880 if (tcsetpgrp(shell_terminal
, pi
->pgrp
) && errno
!= ENOTTY
)
1881 perror_msg("tcsetpgrp-3");
1882 rcode
= checkjobs(pi
);
1883 /* move the shell to the foreground */
1884 if (tcsetpgrp(shell_terminal
, getpgid(0)) && errno
!= ENOTTY
)
1885 perror_msg("tcsetpgrp-4");
1887 rcode
= checkjobs(pi
);
1889 debug_printf("checkjobs returned %d\n",rcode
);
1891 last_return_code
=rcode
;
1894 last_return_code
= -rcode
- 2;
1895 return -2; /* exit */
1897 last_return_code
=(rcode
== 0) ? 0 : 1;
1900 pi
->num_progs
= save_num_progs
; /* restore number of programs */
1902 if ( rmode
== RES_IF
|| rmode
== RES_ELIF
)
1903 next_if_code
=rcode
; /* can be overwritten a number of times */
1904 if (rmode
== RES_WHILE
)
1905 flag_rep
= !last_return_code
;
1906 if (rmode
== RES_UNTIL
)
1907 flag_rep
= last_return_code
;
1908 if ( (rcode
==EXIT_SUCCESS
&& pi
->followup
==PIPE_OR
) ||
1909 (rcode
!=EXIT_SUCCESS
&& pi
->followup
==PIPE_AND
) )
1910 skip_more_in_this_rmode
=rmode
;
1918 /* broken, of course, but OK for testing */
1919 static char *indenter(int i
)
1921 static char blanks
[]=" ";
1922 return &blanks
[sizeof(blanks
)-i
-1];
1925 /* return code is the exit status of the pipe */
1926 static int free_pipe(struct pipe
*pi
, int indent
)
1929 struct child_prog
*child
;
1931 struct redir_struct
*r
, *rnext
;
1933 int a
, i
, ret_code
=0;
1934 char *ind
= indenter(indent
);
1937 if (pi
->stopped_progs
> 0)
1939 final_printf("%s run pipe: (pid %d)\n",ind
,getpid());
1941 for (i
=0; i
<pi
->num_progs
; i
++) {
1942 child
= &pi
->progs
[i
];
1943 final_printf("%s command %d:\n",ind
,i
);
1945 for (a
=0,p
=child
->argv
; *p
; a
++,p
++) {
1946 final_printf("%s argv[%d] = %s\n",ind
,a
,*p
);
1949 globfree(&child
->glob_result
);
1951 for (a
= 0; a
< child
->argc
; a
++) {
1952 free(child
->argv
[a
]);
1958 } else if (child
->group
) {
1960 final_printf("%s begin group (subshell:%d)\n",ind
, child
->subshell
);
1962 ret_code
= free_pipe_list(child
->group
,indent
+3);
1963 final_printf("%s end group\n",ind
);
1965 final_printf("%s (nil)\n",ind
);
1968 for (r
=child
->redirects
; r
; r
=rnext
) {
1969 final_printf("%s redirect %d%s", ind
, r
->fd
, redir_table
[r
->type
].descrip
);
1971 /* guard against the case >$FOO, where foo is unset or blank */
1972 if (r
->word
.gl_pathv
) {
1973 final_printf(" %s\n", *r
->word
.gl_pathv
);
1977 final_printf("&%d\n", r
->dup
);
1982 child
->redirects
=NULL
;
1985 free(pi
->progs
); /* children are an array, they get freed all at once */
1990 static int free_pipe_list(struct pipe
*head
, int indent
)
1992 int rcode
=0; /* if list has no members */
1993 struct pipe
*pi
, *next
;
1994 char *ind
= indenter(indent
);
1995 for (pi
=head
; pi
; pi
=next
) {
1996 final_printf("%s pipe reserved mode %d\n", ind
, pi
->r_mode
);
1997 rcode
= free_pipe(pi
, indent
);
1998 final_printf("%s pipe followup code %d\n", ind
, pi
->followup
);
2006 /* Select which version we will use */
2007 static int run_list(struct pipe
*pi
)
2013 rcode
= run_list_real(pi
);
2017 /* free_pipe_list has the side effect of clearing memory
2018 * In the long run that function can be merged with run_list_real,
2019 * but doing that now would hobble the debugging effort. */
2020 free_pipe_list(pi
,0);
2024 /* The API for glob is arguably broken. This routine pushes a non-matching
2025 * string into the output structure, removing non-backslashed backslashes.
2026 * If someone can prove me wrong, by performing this function within the
2027 * original glob(3) api, feel free to rewrite this routine into oblivion.
2028 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2029 * XXX broken if the last character is '\\', check that before calling.
2032 static int globhack(const char *src
, int flags
, glob_t
*pglob
)
2037 for (cnt
=1, s
=src
; s
&& *s
; s
++) {
2038 if (*s
== '\\') s
++;
2042 if (!dest
) return GLOB_NOSPACE
;
2043 if (!(flags
& GLOB_APPEND
)) {
2044 pglob
->gl_pathv
=NULL
;
2049 pathc
= ++pglob
->gl_pathc
;
2050 pglob
->gl_pathv
= realloc(pglob
->gl_pathv
, (pathc
+1)*sizeof(*pglob
->gl_pathv
));
2051 if (pglob
->gl_pathv
== NULL
) return GLOB_NOSPACE
;
2052 pglob
->gl_pathv
[pathc
-1]=dest
;
2053 pglob
->gl_pathv
[pathc
]=NULL
;
2054 for (s
=src
; s
&& *s
; s
++, dest
++) {
2055 if (*s
== '\\') s
++;
2062 /* XXX broken if the last character is '\\', check that before calling */
2063 static int glob_needed(const char *s
)
2066 if (*s
== '\\') s
++;
2067 if (strchr("*[?",*s
)) return 1;
2073 static void globprint(glob_t
*pglob
)
2076 debug_printf("glob_t at %p:\n", pglob
);
2077 debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
2078 pglob
->gl_pathc
, pglob
->gl_pathv
, pglob
->gl_offs
, pglob
->gl_flags
);
2079 for (i
=0; i
<pglob
->gl_pathc
; i
++)
2080 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i
,
2081 pglob
->gl_pathv
[i
], pglob
->gl_pathv
[i
]);
2085 static int xglob(o_string
*dest
, int flags
, glob_t
*pglob
)
2089 /* short-circuit for null word */
2090 /* we can code this better when the debug_printf's are gone */
2091 if (dest
->length
== 0) {
2092 if (dest
->nonnull
) {
2093 /* bash man page calls this an "explicit" null */
2094 gr
= globhack(dest
->data
, flags
, pglob
);
2095 debug_printf("globhack returned %d\n",gr
);
2099 } else if (glob_needed(dest
->data
)) {
2100 gr
= glob(dest
->data
, flags
, NULL
, pglob
);
2101 debug_printf("glob returned %d\n",gr
);
2102 if (gr
== GLOB_NOMATCH
) {
2103 /* quote removal, or more accurately, backslash removal */
2104 gr
= globhack(dest
->data
, flags
, pglob
);
2105 debug_printf("globhack returned %d\n",gr
);
2108 gr
= globhack(dest
->data
, flags
, pglob
);
2109 debug_printf("globhack returned %d\n",gr
);
2111 if (gr
== GLOB_NOSPACE
)
2112 error_msg_and_die("out of memory during glob");
2113 if (gr
!= 0) { /* GLOB_ABORTED ? */
2114 error_msg("glob(3) error %d",gr
);
2116 /* globprint(glob_target); */
2122 static char *get_dollar_var(char ch
);
2125 /* This is used to get/check local shell variables */
2126 char *get_local_var(const char *s
)
2128 struct variables
*cur
;
2135 return get_dollar_var(s
[1]);
2138 for (cur
= top_vars
; cur
; cur
=cur
->next
)
2139 if(strcmp(cur
->name
, s
)==0)
2144 /* This is used to set local shell variables
2145 flg_export==0 if only local (not exporting) variable
2146 flg_export==1 if "new" exporting environ
2147 flg_export>1 if current startup environ (not call putenv()) */
2148 int set_local_var(const char *s
, int flg_export
)
2152 struct variables
*cur
;
2155 /* might be possible! */
2163 if (getenv(name
) != NULL
) {
2165 "There is a global environment variable with the same name.\n");
2170 /* Assume when we enter this function that we are already in
2171 * NAME=VALUE format. So the first order of business is to
2172 * split 's' on the '=' into 'name' and 'value' */
2173 value
= strchr(name
, '=');
2174 if (value
== NULL
&& ++value
== NULL
) {
2180 for(cur
= top_vars
; cur
; cur
= cur
->next
) {
2181 if(strcmp(cur
->name
, name
)==0)
2186 if(strcmp(cur
->value
, value
)==0) {
2187 if(flg_export
>0 && cur
->flg_export
==0)
2188 cur
->flg_export
=flg_export
;
2192 if(cur
->flg_read_only
) {
2193 error_msg("%s: readonly variable", name
);
2196 if(flg_export
>0 || cur
->flg_export
>1)
2200 cur
->value
= strdup(value
);
2204 cur
= malloc(sizeof(struct variables
));
2208 cur
->name
= strdup(name
);
2209 if (cur
->name
== NULL
) {
2213 struct variables
*bottom
= top_vars
;
2214 cur
->value
= strdup(value
);
2216 cur
->flg_export
= flg_export
;
2217 cur
->flg_read_only
= 0;
2218 while(bottom
->next
) bottom
=bottom
->next
;
2225 if(result
==0 && cur
->flg_export
==1) {
2227 result
= putenv(name
);
2232 if(result
>0) /* equivalent to previous set */
2239 void unset_local_var(const char *name
)
2241 struct variables
*cur
;
2244 for (cur
= top_vars
; cur
; cur
=cur
->next
) {
2245 if(strcmp(cur
->name
, name
)==0)
2249 struct variables
*next
= top_vars
;
2250 if(cur
->flg_read_only
) {
2251 error_msg("%s: readonly variable", name
);
2256 unsetenv(cur
->name
);
2260 while (next
->next
!= cur
)
2262 next
->next
= cur
->next
;
2269 static int is_assignment(const char *s
)
2274 if (!isalpha(*s
)) return 0;
2276 while(isalnum(*s
) || *s
=='_') ++s
;
2281 /* the src parameter allows us to peek forward to a possible &n syntax
2282 * for file descriptor duplication, e.g., "2>&1".
2283 * Return code is 0 normally, 1 if a syntax error is detected in src.
2284 * Resource errors (in xmalloc) cause the process to exit */
2285 static int setup_redirect(struct p_context
*ctx
, int fd
, redir_type style
,
2286 struct in_str
*input
)
2288 struct child_prog
*child
=ctx
->child
;
2289 struct redir_struct
*redir
= child
->redirects
;
2290 struct redir_struct
*last_redir
=NULL
;
2292 /* Create a new redir_struct and drop it onto the end of the linked list */
2297 redir
= xmalloc(sizeof(struct redir_struct
));
2299 redir
->word
.gl_pathv
=NULL
;
2301 last_redir
->next
=redir
;
2303 child
->redirects
=redir
;
2307 redir
->fd
= (fd
==-1) ? redir_table
[style
].default_fd
: fd
;
2309 debug_printf("Redirect type %d%s\n", redir
->fd
, redir_table
[style
].descrip
);
2311 /* Check for a '2>&1' type redirect */
2312 redir
->dup
= redirect_dup_num(input
);
2313 if (redir
->dup
== -2) return 1; /* syntax error */
2314 if (redir
->dup
!= -1) {
2315 /* Erik had a check here that the file descriptor in question
2316 * is legit; I postpone that to "run time"
2317 * A "-" representation of "close me" shows up as a -3 here */
2318 debug_printf("Duplicating redirect '%d>&%d'\n", redir
->fd
, redir
->dup
);
2320 /* We do _not_ try to open the file that src points to,
2321 * since we need to return and let src be expanded first.
2322 * Set ctx->pending_redirect, so we know what to do at the
2323 * end of the next parsed word.
2325 ctx
->pending_redirect
= redir
;
2331 static struct pipe
*new_pipe(void)
2334 pi
= xmalloc(sizeof(struct pipe
));
2338 pi
->followup
= 0; /* invalid */
2339 pi
->r_mode
= RES_NONE
;
2343 static void initialize_context(struct p_context
*ctx
)
2347 ctx
->pending_redirect
=NULL
;
2350 ctx
->list_head
=new_pipe();
2351 ctx
->pipe
=ctx
->list_head
;
2357 done_command(ctx
); /* creates the memory for working child */
2360 /* normal return is 0
2361 * if a reserved word is found, and processed, return 1
2362 * should handle if, then, elif, else, fi, for, while, until, do, done.
2363 * case, function, and select are obnoxious, save those for later.
2365 struct reserved_combo
{
2370 /* Mostly a list of accepted follow-up reserved words.
2371 * FLAG_END means we are done with the sequence, and are ready
2372 * to turn the compound list into a command.
2373 * FLAG_START means the word must start a new compound list.
2375 static struct reserved_combo reserved_list
[] = {
2376 { "if", RES_IF
, FLAG_THEN
| FLAG_START
},
2377 { "then", RES_THEN
, FLAG_ELIF
| FLAG_ELSE
| FLAG_FI
},
2378 { "elif", RES_ELIF
, FLAG_THEN
},
2379 { "else", RES_ELSE
, FLAG_FI
},
2380 { "fi", RES_FI
, FLAG_END
},
2381 { "for", RES_FOR
, FLAG_IN
| FLAG_START
},
2382 { "while", RES_WHILE
, FLAG_DO
| FLAG_START
},
2383 { "until", RES_UNTIL
, FLAG_DO
| FLAG_START
},
2384 { "in", RES_IN
, FLAG_DO
},
2385 { "do", RES_DO
, FLAG_DONE
},
2386 { "done", RES_DONE
, FLAG_END
}
2388 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2390 static int reserved_word(o_string
*dest
, struct p_context
*ctx
)
2392 struct reserved_combo
*r
;
2393 for (r
=reserved_list
;
2394 r
<reserved_list
+NRES
; r
++) {
2395 if (strcmp(dest
->data
, r
->literal
) == 0) {
2396 debug_printf("found reserved word %s, code %d\n",r
->literal
,r
->code
);
2397 if (r
->flag
& FLAG_START
) {
2398 struct p_context
*new = xmalloc(sizeof(struct p_context
));
2399 debug_printf("push stack\n");
2400 if (ctx
->w
== RES_IN
|| ctx
->w
== RES_FOR
) {
2407 *new = *ctx
; /* physical copy */
2408 initialize_context(ctx
);
2410 } else if ( ctx
->w
== RES_NONE
|| ! (ctx
->old_flag
& (1<<r
->code
))) {
2417 ctx
->old_flag
= r
->flag
;
2418 if (ctx
->old_flag
& FLAG_END
) {
2419 struct p_context
*old
;
2420 debug_printf("pop stack\n");
2421 done_pipe(ctx
,PIPE_SEQ
);
2423 old
->child
->group
= ctx
->list_head
;
2425 old
->child
->subshell
= 0;
2427 *ctx
= *old
; /* physical copy */
2437 /* normal return is 0.
2438 * Syntax or xglob errors return 1. */
2439 static int done_word(o_string
*dest
, struct p_context
*ctx
)
2441 struct child_prog
*child
=ctx
->child
;
2443 glob_t
*glob_target
;
2450 debug_printf("done_word: %s %p\n", dest
->data
, child
);
2451 if (dest
->length
== 0 && !dest
->nonnull
) {
2452 debug_printf(" true null, ignored\n");
2456 if (ctx
->pending_redirect
) {
2457 glob_target
= &ctx
->pending_redirect
->word
;
2462 return 1; /* syntax error, groups and arglists don't mix */
2464 if (!child
->argv
&& (ctx
->type
& FLAG_PARSE_SEMICOLON
)) {
2465 debug_printf("checking %s for reserved-ness\n",dest
->data
);
2466 if (reserved_word(dest
,ctx
)) return ctx
->w
==RES_SNTX
;
2469 glob_target
= &child
->glob_result
;
2470 if (child
->argv
) flags
|= GLOB_APPEND
;
2472 for (cnt
= 1, s
= dest
->data
; s
&& *s
; s
++) {
2473 if (*s
== '\\') s
++;
2478 if ( child
->argv
== NULL
) {
2481 argc
= ++child
->argc
;
2482 child
->argv
= realloc(child
->argv
, (argc
+1)*sizeof(*child
->argv
));
2483 if (child
->argv
== NULL
) return 1;
2484 child
->argv
[argc
-1]=str
;
2485 child
->argv
[argc
]=NULL
;
2486 for (s
= dest
->data
; s
&& *s
; s
++,str
++) {
2487 if (*s
== '\\') s
++;
2494 gr
= xglob(dest
, flags
, glob_target
);
2495 if (gr
!= 0) return 1;
2500 if (ctx
->pending_redirect
) {
2501 ctx
->pending_redirect
=NULL
;
2502 if (glob_target
->gl_pathc
!= 1) {
2503 error_msg("ambiguous redirect");
2507 child
->argv
= glob_target
->gl_pathv
;
2510 if (ctx
->w
== RES_FOR
) {
2511 done_word(dest
,ctx
);
2512 done_pipe(ctx
,PIPE_SEQ
);
2517 /* The only possible error here is out of memory, in which case
2519 static int done_command(struct p_context
*ctx
)
2521 /* The child is really already in the pipe structure, so
2522 * advance the pipe counter and make a new, null child.
2523 * Only real trickiness here is that the uncommitted
2524 * child structure, to which ctx->child points, is not
2525 * counted in pi->num_progs. */
2526 struct pipe
*pi
=ctx
->pipe
;
2527 struct child_prog
*prog
=ctx
->child
;
2529 if (prog
&& prog
->group
== NULL
2530 && prog
->argv
== NULL
2532 && prog
->redirects
== NULL
) {
2536 debug_printf("done_command: skipping null command\n");
2540 debug_printf("done_command: num_progs incremented to %d\n",pi
->num_progs
);
2542 debug_printf("done_command: initializing\n");
2544 pi
->progs
= xrealloc(pi
->progs
, sizeof(*pi
->progs
) * (pi
->num_progs
+1));
2546 prog
= pi
->progs
+ pi
->num_progs
;
2548 prog
->redirects
= NULL
;
2552 prog
->is_stopped
= 0;
2556 prog
->glob_result
.gl_pathv
= NULL
;
2561 prog
->type
= ctx
->type
;
2563 /* but ctx->pipe and ctx->list_head remain unchanged */
2567 static int done_pipe(struct p_context
*ctx
, pipe_style type
)
2570 done_command(ctx
); /* implicit closure of previous command */
2571 debug_printf("done_pipe, type %d\n", type
);
2572 ctx
->pipe
->followup
= type
;
2573 ctx
->pipe
->r_mode
= ctx
->w
;
2575 ctx
->pipe
->next
= new_p
;
2578 done_command(ctx
); /* set up new pipe to accept commands */
2583 /* peek ahead in the in_str to find out if we have a "&n" construct,
2584 * as in "2>&1", that represents duplicating a file descriptor.
2585 * returns either -2 (syntax error), -1 (no &), or the number found.
2587 static int redirect_dup_num(struct in_str
*input
)
2591 if (ch
!= '&') return -1;
2593 b_getch(input
); /* get the & */
2597 return -3; /* "-" represents "close me" */
2599 while (isdigit(ch
)) {
2607 error_msg("ambiguous redirect");
2611 /* If a redirect is immediately preceded by a number, that number is
2612 * supposed to tell which file descriptor to redirect. This routine
2613 * looks for such preceding numbers. In an ideal world this routine
2614 * needs to handle all the following classes of redirects...
2615 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2616 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2617 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2618 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2619 * A -1 output from this program means no valid number was found, so the
2620 * caller should use the appropriate default for this redirection.
2622 static int redirect_opt_num(o_string
*o
)
2626 if (o
->length
==0) return -1;
2627 for(num
=0; num
<o
->length
; num
++) {
2628 if (!isdigit(*(o
->data
+num
))) {
2632 /* reuse num (and save an int) */
2638 FILE *generate_stream_from_list(struct pipe
*head
)
2642 int pid
, channel
[2];
2643 if (pipe(channel
)<0) perror_msg_and_die("pipe");
2646 perror_msg_and_die("fork");
2647 } else if (pid
==0) {
2649 if (channel
[1] != 1) {
2654 #define SURROGATE "surrogate response"
2655 write(1,SURROGATE
,sizeof(SURROGATE
));
2656 _exit(run_list(head
));
2658 _exit(run_list_real(head
)); /* leaks memory */
2661 debug_printf("forked child %d\n",pid
);
2663 pf
= fdopen(channel
[0],"r");
2664 debug_printf("pipe on FILE *%p\n",pf
);
2666 free_pipe_list(head
,0);
2667 pf
=popen("echo surrogate response","r");
2668 debug_printf("started fake pipe on FILE *%p\n",pf
);
2673 /* this version hacked for testing purposes */
2674 /* return code is exit status of the process that is run. */
2675 static int process_command_subs(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
, int subst_end
)
2678 o_string result
=NULL_O_STRING
;
2679 struct p_context inner
;
2681 struct in_str pipe_str
;
2682 initialize_context(&inner
);
2684 /* recursion to generate command */
2685 retcode
= parse_stream(&result
, &inner
, input
, subst_end
);
2686 if (retcode
!= 0) return retcode
; /* syntax error or EOF */
2687 done_word(&result
, &inner
);
2688 done_pipe(&inner
, PIPE_SEQ
);
2691 p
=generate_stream_from_list(inner
.list_head
);
2692 if (p
==NULL
) return 1;
2693 mark_open(fileno(p
));
2694 setup_file_in_str(&pipe_str
, p
);
2696 /* now send results of command back into original context */
2697 retcode
= parse_stream(dest
, ctx
, &pipe_str
, '\0');
2698 /* XXX In case of a syntax error, should we try to kill the child?
2699 * That would be tough to do right, so just read until EOF. */
2701 while (b_getch(&pipe_str
)!=EOF
) { /* discard */ };
2704 debug_printf("done reading from pipe, pclose()ing\n");
2705 /* This is the step that wait()s for the child. Should be pretty
2706 * safe, since we just read an EOF from its stdout. We could try
2707 * to better, by using wait(), and keeping track of background jobs
2708 * at the same time. That would be a lot of work, and contrary
2709 * to the KISS philosophy of this program. */
2710 mark_closed(fileno(p
));
2712 free_pipe_list(inner
.list_head
,0);
2713 debug_printf("pclosed, retcode=%d\n",retcode
);
2714 /* XXX this process fails to trim a single trailing newline */
2718 static int parse_group(o_string
*dest
, struct p_context
*ctx
,
2719 struct in_str
*input
, int ch
)
2722 struct p_context sub
;
2723 struct child_prog
*child
= ctx
->child
;
2726 return 1; /* syntax error, groups and arglists don't mix */
2728 initialize_context(&sub
);
2730 case '(': endch
=')'; child
->subshell
=1; break;
2731 case '{': endch
='}'; break;
2732 default: syntax(); /* really logic error */
2734 rcode
=parse_stream(dest
,&sub
,input
,endch
);
2735 done_word(dest
,&sub
); /* finish off the final word in the subcontext */
2736 done_pipe(&sub
, PIPE_SEQ
); /* and the final command there, too */
2737 child
->group
= sub
.list_head
;
2739 /* child remains "open", available for possible redirects */
2743 /* basically useful version until someone wants to get fancier,
2744 * see the bash man page under "Parameter Expansion" */
2745 static char *lookup_param(char *src
)
2749 char *default_val
= NULL
;
2751 int expand_empty
= 0;
2756 sep
= strchr(src
, ':');
2760 if (*(sep
+ 1) == '-')
2761 default_val
= sep
+2;
2762 if (*(sep
+ 1) == '=') {
2763 default_val
= sep
+2;
2766 if (*(sep
+ 1) == '+') {
2767 default_val
= sep
+2;
2774 p
= get_local_var(src
);
2776 if (!p
|| strlen(p
) == 0) {
2779 char *var
= malloc(strlen(src
)+strlen(default_val
)+2);
2781 sprintf(var
, "%s=%s", src
, default_val
);
2782 set_local_var(var
, 0);
2786 } else if (expand_empty
) {
2797 static char *get_dollar_var(char ch
)
2799 static char buf
[40];
2804 sprintf(buf
, "%u", (unsigned int)last_return_code
);
2813 /* return code: 0 for OK, 1 for syntax error */
2814 static int handle_dollar(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
)
2824 int ch
= input
->peek(input
); /* first character after the $ */
2825 debug_printf("handle_dollar: ch=%c\n",ch
);
2827 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2829 while(ch
=b_peek(input
),isalnum(ch
) || ch
=='_') {
2833 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2835 } else if (isdigit(ch
)) {
2836 i
= ch
-'0'; /* XXX is $0 special? */
2837 if (i
<global_argc
) {
2838 parse_string(dest
, ctx
, global_argv
[i
]); /* recursion */
2842 } else switch (ch
) {
2845 b_adduint(dest
,getpid());
2849 if (last_bg_pid
> 0) b_adduint(dest
, last_bg_pid
);
2855 b_adduint(dest
,last_return_code
);
2858 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2859 b_addchr(dest
, '$');
2860 b_addchr(dest
, '?');
2861 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2867 b_adduint(dest
,global_argc
? global_argc
-1 : 0);
2872 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2875 /* XXX maybe someone will try to escape the '}' */
2876 while(ch
=b_getch(input
),ch
!=EOF
&& ch
!='}') {
2883 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2888 process_command_subs(dest
, ctx
, input
, ')');
2892 for (i
=1; i
<global_argc
; i
++) {
2893 parse_string(dest
, ctx
, global_argv
[i
]);
2894 if (i
+1 < global_argc
) parse_string(dest
, ctx
, sep
);
2900 /* still unhandled, but should be eventually */
2901 error_msg("unhandled syntax: $%c",ch
);
2906 b_addqchr(dest
,'$',dest
->quote
);
2908 /* Eat the character if the flag was set. If the compiler
2909 * is smart enough, we could substitute "b_getch(input);"
2910 * for all the "advance = 1;" above, and also end up with
2911 * a nice size-optimized program. Hah! That'll be the day.
2913 if (advance
) b_getch(input
);
2918 int parse_string(o_string
*dest
, struct p_context
*ctx
, const char *src
)
2921 setup_string_in_str(&foo
, src
);
2922 return parse_stream(dest
, ctx
, &foo
, '\0');
2926 /* return code is 0 for normal exit, 1 for syntax error */
2927 static int parse_stream(o_string
*dest
, struct p_context
*ctx
,
2928 struct in_str
*input
, int end_trigger
)
2933 redir_type redir_style
;
2937 /* Only double-quote state is handled in the state variable dest->quote.
2938 * A single-quote triggers a bypass of the main loop until its mate is
2939 * found. When recursing, quote state is passed in via dest->quote. */
2941 debug_printf("parse_stream, end_trigger=%d\n",end_trigger
);
2942 while ((ch
=b_getch(input
))!=EOF
) {
2945 if (input
->__promptme
== 0) return 1;
2947 next
= (ch
== '\n') ? 0 : b_peek(input
);
2949 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2950 ch
>= ' ' ? ch
: '.', ch
, m
,
2951 dest
->quote
, ctx
->stack
== NULL
? '*' : '.');
2953 if (m
==0 || ((m
==1 || m
==2) && dest
->quote
)) {
2954 b_addqchr(dest
, ch
, dest
->quote
);
2956 if (m
==2) { /* unquoted IFS */
2957 if (done_word(dest
, ctx
)) {
2960 /* If we aren't performing a substitution, treat a newline as a
2961 * command separator. */
2962 if (end_trigger
!= '\0' && ch
=='\n')
2963 done_pipe(ctx
,PIPE_SEQ
);
2965 if (ch
== end_trigger
&& !dest
->quote
&& ctx
->w
==RES_NONE
) {
2966 debug_printf("leaving parse_stream (triggered)\n");
2971 /* Yahoo! Time to run with it! */
2972 done_pipe(ctx
,PIPE_SEQ
);
2973 run_list(ctx
->list_head
);
2974 initialize_context(ctx
);
2977 if (m
!=2) switch (ch
) {
2979 if (dest
->length
== 0 && !dest
->quote
) {
2980 while(ch
=b_peek(input
),ch
!=EOF
&& ch
!='\n') { b_getch(input
); }
2982 b_addqchr(dest
, ch
, dest
->quote
);
2990 b_addqchr(dest
, '\\', dest
->quote
);
2991 b_addqchr(dest
, b_getch(input
), dest
->quote
);
2994 if (handle_dollar(dest
, ctx
, input
)!=0) return 1;
2998 while(ch
=b_getch(input
),ch
!=EOF
&& ch
!='\'') {
3000 if(input
->__promptme
== 0) return 1;
3011 dest
->quote
= !dest
->quote
;
3015 process_command_subs(dest
, ctx
, input
, '`');
3018 redir_fd
= redirect_opt_num(dest
);
3019 done_word(dest
, ctx
);
3020 redir_style
=REDIRECT_OVERWRITE
;
3022 redir_style
=REDIRECT_APPEND
;
3024 } else if (next
== '(') {
3025 syntax(); /* until we support >(list) Process Substitution */
3028 setup_redirect(ctx
, redir_fd
, redir_style
, input
);
3031 redir_fd
= redirect_opt_num(dest
);
3032 done_word(dest
, ctx
);
3033 redir_style
=REDIRECT_INPUT
;
3035 redir_style
=REDIRECT_HEREIS
;
3037 } else if (next
== '>') {
3038 redir_style
=REDIRECT_IO
;
3040 } else if (next
== '(') {
3041 syntax(); /* until we support <(list) Process Substitution */
3044 setup_redirect(ctx
, redir_fd
, redir_style
, input
);
3048 done_word(dest
, ctx
);
3049 done_pipe(ctx
,PIPE_SEQ
);
3052 done_word(dest
, ctx
);
3055 done_pipe(ctx
,PIPE_AND
);
3058 done_pipe(ctx
,PIPE_BG
);
3066 done_word(dest
, ctx
);
3069 done_pipe(ctx
,PIPE_OR
);
3071 /* we could pick up a file descriptor choice here
3072 * with redirect_opt_num(), but bash doesn't do it.
3073 * "echo foo 2| cat" yields "foo 2". */
3085 if (parse_group(dest
, ctx
, input
, ch
)!=0) return 1;
3089 syntax(); /* Proper use of this character caught by end_trigger */
3093 case SUBSTED_VAR_SYMBOL
:
3095 while (ch
= b_getch(input
), ch
!= EOF
&&
3096 ch
!= SUBSTED_VAR_SYMBOL
) {
3097 debug_printf("subst, pass=%d\n", ch
);
3098 if (input
->__promptme
== 0)
3102 debug_printf("subst, term=%d\n", ch
);
3109 syntax(); /* this is really an internal logic error */
3114 /* complain if quote? No, maybe we just finished a command substitution
3115 * that was quoted. Example:
3116 * $ echo "`cat foo` plus more"
3117 * and we just got the EOF generated by the subshell that ran "cat foo"
3118 * The only real complaint is if we got an EOF when end_trigger != '\0',
3119 * that is, we were really supposed to get end_trigger, and never got
3120 * one before the EOF. Can't use the standard "syntax error" return code,
3121 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3122 debug_printf("leaving parse_stream (EOF)\n");
3123 if (end_trigger
!= '\0') return -1;
3127 static void mapset(const unsigned char *set
, int code
)
3129 const unsigned char *s
;
3130 for (s
=set
; *s
; s
++) map
[*s
] = code
;
3133 static void update_ifs_map(void)
3135 /* char *ifs and char map[256] are both globals. */
3136 ifs
= (uchar
*)getenv("IFS");
3137 if (ifs
== NULL
) ifs
=(uchar
*)" \t\n";
3138 /* Precompute a list of 'flow through' behavior so it can be treated
3139 * quickly up front. Computation is necessary because of IFS.
3140 * Special case handling of IFS == " \t\n" is not implemented.
3141 * The map[] array only really needs two bits each, and on most machines
3142 * that would be faster because of the reduced L1 cache footprint.
3144 memset(map
,0,sizeof(map
)); /* most characters flow through always */
3146 mapset((uchar
*)"\\$'\"`", 3); /* never flow through */
3147 mapset((uchar
*)"<>;&|(){}#", 1); /* flow through if quoted */
3150 uchar subst
[2] = {SUBSTED_VAR_SYMBOL
, 0};
3151 mapset(subst
, 3); /* never flow through */
3153 mapset((uchar
*)"\\$'\"", 3); /* never flow through */
3154 mapset((uchar
*)";&|#", 1); /* flow through if quoted */
3156 mapset(ifs
, 2); /* also flow through if quoted */
3159 /* most recursion does not come through here, the exeception is
3160 * from builtin_source() */
3161 static int parse_stream_outer(struct in_str
*inp
, int flag
)
3164 struct p_context ctx
;
3165 o_string temp
=NULL_O_STRING
;
3172 initialize_context(&ctx
);
3174 if (!(flag
& FLAG_PARSE_SEMICOLON
) || (flag
& FLAG_REPARSING
)) mapset((uchar
*)";$&|", 0);
3176 rcode
= parse_stream(&temp
, &ctx
, inp
, '\n');
3178 if (rcode
== 1) flag_repeat
= 0;
3180 if (rcode
!= 1 && ctx
.old_flag
!= 0) {
3186 if (rcode
!= 1 && ctx
.old_flag
== 0) {
3187 done_word(&temp
, &ctx
);
3188 done_pipe(&ctx
,PIPE_SEQ
);
3190 run_list(ctx
.list_head
);
3192 code
= run_list(ctx
.list_head
);
3193 if (code
== -2) { /* exit */
3196 /* XXX hackish way to not allow exit from main loop */
3197 if (inp
->peek
== file_peek
) {
3198 printf("exit not allowed from main input shell.\n");
3207 if (ctx
.old_flag
!= 0) {
3212 if (inp
->__promptme
== 0) printf("<INTERRUPT>\n");
3213 inp
->__promptme
= 1;
3218 free_pipe_list(ctx
.list_head
,0);
3221 } while (rcode
!= -1 && !(flag
& FLAG_EXIT_FROM_LOOP
)); /* loop on syntax errors, return on EOF */
3225 return (code
!= 0) ? 1 : 0;
3226 #endif /* __U_BOOT__ */
3230 static int parse_string_outer(const char *s
, int flag
)
3232 int parse_string_outer(const char *s
, int flag
)
3233 #endif /* __U_BOOT__ */
3235 struct in_str input
;
3241 if (!(p
= strchr(s
, '\n')) || *++p
) {
3242 p
= xmalloc(strlen(s
) + 2);
3245 setup_string_in_str(&input
, p
);
3246 rcode
= parse_stream_outer(&input
, flag
);
3251 setup_string_in_str(&input
, s
);
3252 return parse_stream_outer(&input
, flag
);
3259 static int parse_file_outer(FILE *f
)
3261 int parse_file_outer(void)
3265 struct in_str input
;
3267 setup_file_in_str(&input
, f
);
3269 setup_file_in_str(&input
);
3271 rcode
= parse_stream_outer(&input
, FLAG_PARSE_SEMICOLON
);
3276 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3277 static void u_boot_hush_reloc(void)
3280 struct reserved_combo
*r
;
3282 for (r
=reserved_list
; r
<reserved_list
+NRES
; r
++) {
3283 addr
= (ulong
) (r
->literal
) + gd
->reloc_off
;
3284 r
->literal
= (char *)addr
;
3289 int u_boot_hush_start(void)
3291 if (top_vars
== NULL
) {
3292 top_vars
= malloc(sizeof(struct variables
));
3293 top_vars
->name
= "HUSH_VERSION";
3294 top_vars
->value
= "0.01";
3295 top_vars
->next
= NULL
;
3296 top_vars
->flg_export
= 0;
3297 top_vars
->flg_read_only
= 1;
3298 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3299 u_boot_hush_reloc();
3305 static void *xmalloc(size_t size
)
3309 if (!(p
= malloc(size
))) {
3310 printf("ERROR : memory not allocated\n");
3316 static void *xrealloc(void *ptr
, size_t size
)
3320 if (!(p
= realloc(ptr
, size
))) {
3321 printf("ERROR : memory not allocated\n");
3326 #endif /* __U_BOOT__ */
3329 /* Make sure we have a controlling tty. If we get started under a job
3330 * aware app (like bash for example), make sure we are now in charge so
3331 * we don't fight over who gets the foreground */
3332 static void setup_job_control(void)
3334 static pid_t shell_pgrp
;
3335 /* Loop until we are in the foreground. */
3336 while (tcgetpgrp (shell_terminal
) != (shell_pgrp
= getpgrp ()))
3337 kill (- shell_pgrp
, SIGTTIN
);
3339 /* Ignore interactive and job-control signals. */
3340 signal(SIGINT
, SIG_IGN
);
3341 signal(SIGQUIT
, SIG_IGN
);
3342 signal(SIGTERM
, SIG_IGN
);
3343 signal(SIGTSTP
, SIG_IGN
);
3344 signal(SIGTTIN
, SIG_IGN
);
3345 signal(SIGTTOU
, SIG_IGN
);
3346 signal(SIGCHLD
, SIG_IGN
);
3348 /* Put ourselves in our own process group. */
3350 shell_pgrp
= getpid ();
3351 setpgid (shell_pgrp
, shell_pgrp
);
3353 /* Grab control of the terminal. */
3354 tcsetpgrp(shell_terminal
, shell_pgrp
);
3357 int hush_main(int argc
, char * const *argv
)
3363 /* XXX what should these be while sourcing /etc/profile? */
3367 /* (re?) initialize globals. Sometimes hush_main() ends up calling
3368 * hush_main(), therefore we cannot rely on the BSS to zero out this
3369 * stuff. Reset these to 0 every time. */
3371 /* map[] is taken care of with call to update_ifs_map() */
3374 close_me_head
= NULL
;
3379 /* Initialize some more globals to non-zero values */
3381 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3382 cmdedit_set_initial_prompt();
3388 /* initialize our shell local variables with the values
3389 * currently living in the environment */
3392 set_local_var(*e
, 2); /* without call putenv() */
3395 last_return_code
=EXIT_SUCCESS
;
3398 if (argv
[0] && argv
[0][0] == '-') {
3399 debug_printf("\nsourcing /etc/profile\n");
3400 if ((input
= fopen("/etc/profile", "r")) != NULL
) {
3401 mark_open(fileno(input
));
3402 parse_file_outer(input
);
3403 mark_closed(fileno(input
));
3409 while ((opt
= getopt(argc
, argv
, "c:xif")) > 0) {
3413 global_argv
= argv
+optind
;
3414 global_argc
= argc
-optind
;
3415 opt
= parse_string_outer(optarg
, FLAG_PARSE_SEMICOLON
);
3427 fprintf(stderr
, "Usage: sh [FILE]...\n"
3428 " or: sh -c command [args]...\n\n");
3435 /* A shell is interactive if the `-i' flag was given, or if all of
3436 * the following conditions are met:
3438 * no arguments remaining or the -s flag given
3439 * standard input is a terminal
3440 * standard output is a terminal
3441 * Refer to Posix.2, the description of the `sh' utility. */
3442 if (argv
[optind
]==NULL
&& input
==stdin
&&
3443 isatty(fileno(stdin
)) && isatty(fileno(stdout
))) {
3447 debug_printf("\ninteractive=%d\n", interactive
);
3449 /* Looks like they want an interactive shell */
3450 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3451 printf( "\n\n" BB_BANNER
" hush - the humble shell v0.01 (testing)\n");
3452 printf( "Enter 'help' for a list of built-in commands.\n\n");
3454 setup_job_control();
3457 if (argv
[optind
]==NULL
) {
3458 opt
=parse_file_outer(stdin
);
3462 debug_printf("\nrunning script '%s'\n", argv
[optind
]);
3463 global_argv
= argv
+optind
;
3464 global_argc
= argc
-optind
;
3465 input
= xfopen(argv
[optind
], "r");
3466 opt
= parse_file_outer(input
);
3468 #ifdef CONFIG_FEATURE_CLEAN_UP
3470 if (cwd
&& cwd
!= unknown
)
3473 struct variables
*cur
, *tmp
;
3474 for(cur
= top_vars
; cur
; cur
= tmp
) {
3476 if (!cur
->flg_read_only
) {
3486 return(opt
?opt
:last_return_code
);
3490 static char *insert_var_value(char *inp
)
3492 return insert_var_value_sub(inp
, 0);
3495 static char *insert_var_value_sub(char *inp
, int tag_subst
)
3497 int res_str_len
= 0;
3500 char *p
, *p1
, *res_str
= NULL
;
3502 while ((p
= strchr(inp
, SPECIAL_VAR_SYMBOL
))) {
3503 /* check the beginning of the string for normal charachters */
3505 /* copy any charachters to the result string */
3507 res_str
= xrealloc(res_str
, (res_str_len
+ len
));
3508 strncpy((res_str
+ res_str_len
), inp
, len
);
3512 /* find the ending marker */
3513 p
= strchr(inp
, SPECIAL_VAR_SYMBOL
);
3515 /* look up the value to substitute */
3516 if ((p1
= lookup_param(inp
))) {
3518 len
= res_str_len
+ strlen(p1
) + 2;
3520 len
= res_str_len
+ strlen(p1
);
3521 res_str
= xrealloc(res_str
, (1 + len
));
3524 * copy the variable value to the result
3527 strcpy((res_str
+ res_str_len
+ 1), p1
);
3530 * mark the replaced text to be accepted as
3533 res_str
[res_str_len
] = SUBSTED_VAR_SYMBOL
;
3534 res_str
[res_str_len
+ 1 + strlen(p1
)] =
3538 * copy the variable value to the result
3541 strcpy((res_str
+ res_str_len
), p1
);
3545 *p
= SPECIAL_VAR_SYMBOL
;
3550 res_str
= xrealloc(res_str
, (1 + res_str_len
+ strlen(inp
)));
3551 strcpy((res_str
+ res_str_len
), inp
);
3552 while ((p
= strchr(res_str
, '\n'))) {
3556 return (res_str
== NULL
) ? inp
: res_str
;
3559 static char **make_list_in(char **inp
, char *name
)
3562 int name_len
= strlen(name
);
3567 /* create list of variable values */
3568 list
= xmalloc(sizeof(*list
));
3569 for (i
= 0; inp
[i
]; i
++) {
3570 p3
= insert_var_value(inp
[i
]);
3577 if ((p2
= strchr(p1
, ' '))) {
3583 /* we use n + 2 in realloc for list,because we add
3584 * new element and then we will add NULL element */
3585 list
= xrealloc(list
, sizeof(*list
) * (n
+ 2));
3586 list
[n
] = xmalloc(2 + name_len
+ len
);
3587 strcpy(list
[n
], name
);
3588 strcat(list
[n
], "=");
3589 strncat(list
[n
], p1
, len
);
3590 list
[n
++][name_len
+ len
+ 1] = '\0';
3593 if (p3
!= inp
[i
]) free(p3
);
3599 /* Make new string for parser */
3600 static char * make_string(char ** inp
)
3609 noeval_str
= get_local_var("HUSH_NO_EVAL");
3610 if (noeval_str
!= NULL
&& *noeval_str
!= '0' && *noeval_str
!= '\0')
3612 for (n
= 0; inp
[n
]; n
++) {
3613 p
= insert_var_value_sub(inp
[n
], noeval
);
3614 str
= xrealloc(str
, (len
+ strlen(p
)));
3621 len
= strlen(str
) + 3;
3622 if (p
!= inp
[n
]) free(p
);
3625 *(str
+ len
) = '\n';
3626 *(str
+ len
+ 1) = '\0';
3631 static int do_showvar(cmd_tbl_t
*cmdtp
, int flag
, int argc
,
3632 char * const argv
[])
3636 struct variables
*cur
;
3638 if (argc
== 1) { /* Print all env variables */
3639 for (cur
= top_vars
; cur
; cur
= cur
->next
) {
3640 printf ("%s=%s\n", cur
->name
, cur
->value
);
3642 puts ("\n ** Abort\n");
3648 for (i
= 1; i
< argc
; ++i
) { /* print single env variables */
3649 char *name
= argv
[i
];
3652 for (cur
= top_vars
; cur
; cur
= cur
->next
) {
3653 if(strcmp (cur
->name
, name
) == 0) {
3655 printf ("%s=%s\n", cur
->name
, cur
->value
);
3658 puts ("\n ** Abort\n");
3663 printf ("## Error: \"%s\" not defined\n", name
);
3671 showvar
, CONFIG_SYS_MAXARGS
, 1, do_showvar
,
3672 "print local hushshell variables",
3673 "\n - print values of all hushshell variables\n"
3674 "showvar name ...\n"
3675 " - print value of hushshell variable 'name'"
3679 /****************************************************************************/