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 * SPDX-License-Identifier: GPL-2.0+
79 #include <malloc.h> /* malloc, free, realloc*/
80 #include <linux/ctype.h> /* isalpha, isdigit */
81 #include <common.h> /* readline */
83 #include <command.h> /* find_cmd */
84 #ifndef CONFIG_SYS_PROMPT_HUSH_PS2
85 #define CONFIG_SYS_PROMPT_HUSH_PS2 "> "
89 #include <ctype.h> /* isalpha, isdigit */
90 #include <unistd.h> /* getpid */
91 #include <stdlib.h> /* getenv, atoi */
92 #include <string.h> /* strchr */
93 #include <stdio.h> /* popen etc. */
94 #include <glob.h> /* glob, of course */
95 #include <stdarg.h> /* va_list */
98 #include <getopt.h> /* should be pretty obvious */
100 #include <sys/stat.h> /* ulimit */
101 #include <sys/types.h>
102 #include <sys/wait.h>
105 /* #include <dmalloc.h> */
111 #define applet_name "hush"
112 #include "standalone.h"
113 #define hush_main main
114 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
118 #define SPECIAL_VAR_SYMBOL 03
119 #define SUBSTED_VAR_SYMBOL 04
121 #define FLAG_EXIT_FROM_LOOP 1
122 #define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
123 #define FLAG_REPARSING (1 << 2) /* >= 2nd pass */
128 DECLARE_GLOBAL_DATA_PTR
;
130 #define EXIT_SUCCESS 0
132 #define syntax() syntax_err()
133 #define xstrdup strdup
134 #define error_msg printf
138 REDIRECT_OVERWRITE
= 2,
144 /* The descrip member of this structure is only used to make debugging
146 struct {int mode
; int default_fd
; char *descrip
;} redir_table
[] = {
148 { O_RDONLY
, 0, "<" },
149 { O_CREAT
|O_TRUNC
|O_WRONLY
, 1, ">" },
150 { O_CREAT
|O_APPEND
|O_WRONLY
, 1, ">>" },
151 { O_RDONLY
, -1, "<<" },
163 /* might eventually control execution */
180 #define FLAG_END (1<<RES_NONE)
181 #define FLAG_IF (1<<RES_IF)
182 #define FLAG_THEN (1<<RES_THEN)
183 #define FLAG_ELIF (1<<RES_ELIF)
184 #define FLAG_ELSE (1<<RES_ELSE)
185 #define FLAG_FI (1<<RES_FI)
186 #define FLAG_FOR (1<<RES_FOR)
187 #define FLAG_WHILE (1<<RES_WHILE)
188 #define FLAG_UNTIL (1<<RES_UNTIL)
189 #define FLAG_DO (1<<RES_DO)
190 #define FLAG_DONE (1<<RES_DONE)
191 #define FLAG_IN (1<<RES_IN)
192 #define FLAG_START (1<<RES_XXXX)
194 /* This holds pointers to the various results of parsing */
196 struct child_prog
*child
;
197 struct pipe
*list_head
;
200 struct redir_struct
*pending_redirect
;
203 int old_flag
; /* for figuring out valid reserved words */
204 struct p_context
*stack
;
205 int type
; /* define type of parser : ";$" common or special symbol */
206 /* How about quoting status? */
210 struct redir_struct
{
211 redir_type type
; /* type of redirection */
212 int fd
; /* file descriptor being redirected */
213 int dup
; /* -1, or file descriptor being duplicated */
214 struct redir_struct
*next
; /* pointer to the next redirect in the list */
215 glob_t word
; /* *word.gl_pathv is the filename */
221 pid_t pid
; /* 0 if exited */
223 char **argv
; /* program name and arguments */
225 int argc
; /* number of program arguments */
227 struct pipe
*group
; /* if non-NULL, first in group or subshell */
229 int subshell
; /* flag, non-zero if group must be forked */
230 struct redir_struct
*redirects
; /* I/O redirections */
231 glob_t glob_result
; /* result of parameter globbing */
232 int is_stopped
; /* is the program currently running? */
233 struct pipe
*family
; /* pointer back to the child's parent pipe */
235 int sp
; /* number of SPECIAL_VAR_SYMBOL */
241 int jobid
; /* job number */
243 int num_progs
; /* total number of programs in job */
245 int running_progs
; /* number of programs running */
246 char *text
; /* name of job */
247 char *cmdbuf
; /* buffer various argv's point into */
248 pid_t pgrp
; /* process group ID for the job */
250 struct child_prog
*progs
; /* array of commands in pipe */
251 struct pipe
*next
; /* to track background commands */
253 int stopped_progs
; /* number of programs alive, but stopped */
254 int job_context
; /* bitmask defining current context */
256 pipe_style followup
; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
257 reserved_style r_mode
; /* supports if, for, while, until */
263 struct close_me
*next
;
272 struct variables
*next
;
275 /* globals, connect us to the outside world
276 * the first three support $?, $#, and $1 */
279 unsigned int global_argc
;
281 static unsigned int last_return_code
;
283 extern char **environ
; /* This is in <unistd.h>, but protected with __USE_GNU */
286 /* "globals" within this file */
288 static char map
[256];
290 static int fake_mode
;
291 static int interactive
;
292 static struct close_me
*close_me_head
;
293 static const char *cwd
;
294 static struct pipe
*job_list
;
295 static unsigned int last_bg_pid
;
296 static unsigned int last_jobid
;
297 static unsigned int shell_terminal
;
300 struct variables shell_ver
= { "HUSH_VERSION", "0.01", 1, 1, 0 };
301 struct variables
*top_vars
= &shell_ver
;
303 static int flag_repeat
= 0;
304 static int do_repeat
= 0;
305 static struct variables
*top_vars
= NULL
;
306 #endif /*__U_BOOT__ */
308 #define B_CHUNK (100)
318 #define NULL_O_STRING {NULL,0,0,0,0}
319 /* used for initialization:
320 o_string foo = NULL_O_STRING; */
322 /* I can almost use ordinary FILE *. Is open_memstream() universally
323 * available? Where is it documented? */
334 int (*get
) (struct in_str
*);
335 int (*peek
) (struct in_str
*);
337 #define b_getch(input) ((input)->get(input))
338 #define b_peek(input) ((input)->peek(input))
341 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
343 struct built_in_command
{
344 char *cmd
; /* name */
345 char *descr
; /* description */
346 int (*function
) (struct child_prog
*); /* function ptr */
350 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
355 /* This should be in utility.c */
358 static void debug_printf(const char *format
, ...)
361 va_start(args
, format
);
362 vfprintf(stderr
, format
, args
);
366 #define debug_printf(fmt,args...) printf (fmt ,##args)
369 static inline void debug_printf(const char *format
, ...) { }
371 #define final_printf debug_printf
374 static void syntax_err(void) {
375 printf("syntax error\n");
378 static void __syntax(char *file
, int line
) {
379 error_msg("syntax error %s:%d", file
, line
);
381 #define syntax() __syntax(__FILE__, __LINE__)
385 static void *xmalloc(size_t size
);
386 static void *xrealloc(void *ptr
, size_t size
);
388 /* Index of subroutines: */
389 /* function prototypes for builtins */
390 static int builtin_cd(struct child_prog
*child
);
391 static int builtin_env(struct child_prog
*child
);
392 static int builtin_eval(struct child_prog
*child
);
393 static int builtin_exec(struct child_prog
*child
);
394 static int builtin_exit(struct child_prog
*child
);
395 static int builtin_export(struct child_prog
*child
);
396 static int builtin_fg_bg(struct child_prog
*child
);
397 static int builtin_help(struct child_prog
*child
);
398 static int builtin_jobs(struct child_prog
*child
);
399 static int builtin_pwd(struct child_prog
*child
);
400 static int builtin_read(struct child_prog
*child
);
401 static int builtin_set(struct child_prog
*child
);
402 static int builtin_shift(struct child_prog
*child
);
403 static int builtin_source(struct child_prog
*child
);
404 static int builtin_umask(struct child_prog
*child
);
405 static int builtin_unset(struct child_prog
*child
);
406 static int builtin_not_written(struct child_prog
*child
);
408 /* o_string manipulation: */
409 static int b_check_space(o_string
*o
, int len
);
410 static int b_addchr(o_string
*o
, int ch
);
411 static void b_reset(o_string
*o
);
412 static int b_addqchr(o_string
*o
, int ch
, int quote
);
414 static int b_adduint(o_string
*o
, unsigned int i
);
416 /* in_str manipulations: */
417 static int static_get(struct in_str
*i
);
418 static int static_peek(struct in_str
*i
);
419 static int file_get(struct in_str
*i
);
420 static int file_peek(struct in_str
*i
);
422 static void setup_file_in_str(struct in_str
*i
, FILE *f
);
424 static void setup_file_in_str(struct in_str
*i
);
426 static void setup_string_in_str(struct in_str
*i
, const char *s
);
428 /* close_me manipulations: */
429 static void mark_open(int fd
);
430 static void mark_closed(int fd
);
431 static void close_all(void);
433 /* "run" the final data structures: */
434 static char *indenter(int i
);
435 static int free_pipe_list(struct pipe
*head
, int indent
);
436 static int free_pipe(struct pipe
*pi
, int indent
);
437 /* really run the final data structures: */
439 static int setup_redirects(struct child_prog
*prog
, int squirrel
[]);
441 static int run_list_real(struct pipe
*pi
);
443 static void pseudo_exec(struct child_prog
*child
) __attribute__ ((noreturn
));
445 static int run_pipe_real(struct pipe
*pi
);
446 /* extended glob support: */
448 static int globhack(const char *src
, int flags
, glob_t
*pglob
);
449 static int glob_needed(const char *s
);
450 static int xglob(o_string
*dest
, int flags
, glob_t
*pglob
);
452 /* variable assignment: */
453 static int is_assignment(const char *s
);
454 /* data structure manipulation: */
456 static int setup_redirect(struct p_context
*ctx
, int fd
, redir_type style
, struct in_str
*input
);
458 static void initialize_context(struct p_context
*ctx
);
459 static int done_word(o_string
*dest
, struct p_context
*ctx
);
460 static int done_command(struct p_context
*ctx
);
461 static int done_pipe(struct p_context
*ctx
, pipe_style type
);
462 /* primary string parsing: */
464 static int redirect_dup_num(struct in_str
*input
);
465 static int redirect_opt_num(o_string
*o
);
466 static int process_command_subs(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
, int subst_end
);
467 static int parse_group(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
, int ch
);
469 static char *lookup_param(char *src
);
470 static char *make_string(char **inp
);
471 static int handle_dollar(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
);
473 static int parse_string(o_string
*dest
, struct p_context
*ctx
, const char *src
);
475 static int parse_stream(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input0
, int end_trigger
);
477 static int parse_stream_outer(struct in_str
*inp
, int flag
);
479 static int parse_string_outer(const char *s
, int flag
);
480 static int parse_file_outer(FILE *f
);
483 /* job management: */
484 static int checkjobs(struct pipe
* fg_pipe
);
485 static void insert_bg_job(struct pipe
*pi
);
486 static void remove_bg_job(struct pipe
*pi
);
488 /* local variable support */
489 static char **make_list_in(char **inp
, char *name
);
490 static char *insert_var_value(char *inp
);
491 static char *insert_var_value_sub(char *inp
, int tag_subst
);
494 /* Table of built-in functions. They can be forked or not, depending on
495 * context: within pipes, they fork. As simple commands, they do not.
496 * When used in non-forking context, they can change global variables
497 * in the parent shell process. If forked, of course they can not.
498 * For example, 'unset foo | whatever' will parse and run, but foo will
499 * still be set at the end. */
500 static struct built_in_command bltins
[] = {
501 {"bg", "Resume a job in the background", builtin_fg_bg
},
502 {"break", "Exit for, while or until loop", builtin_not_written
},
503 {"cd", "Change working directory", builtin_cd
},
504 {"continue", "Continue for, while or until loop", builtin_not_written
},
505 {"env", "Print all environment variables", builtin_env
},
506 {"eval", "Construct and run shell command", builtin_eval
},
507 {"exec", "Exec command, replacing this shell with the exec'd process",
509 {"exit", "Exit from shell()", builtin_exit
},
510 {"export", "Set environment variable", builtin_export
},
511 {"fg", "Bring job into the foreground", builtin_fg_bg
},
512 {"jobs", "Lists the active jobs", builtin_jobs
},
513 {"pwd", "Print current directory", builtin_pwd
},
514 {"read", "Input environment variable", builtin_read
},
515 {"return", "Return from a function", builtin_not_written
},
516 {"set", "Set/unset shell local variables", builtin_set
},
517 {"shift", "Shift positional parameters", builtin_shift
},
518 {"trap", "Trap signals", builtin_not_written
},
519 {"ulimit","Controls resource limits", builtin_not_written
},
520 {"umask","Sets file creation mask", builtin_umask
},
521 {"unset", "Unset environment variable", builtin_unset
},
522 {".", "Source-in and run commands in a file", builtin_source
},
523 {"help", "List shell built-in commands", builtin_help
},
527 static const char *set_cwd(void)
530 cwd
= NULL
; /* xgetcwd(arg) called free(arg) */
531 cwd
= xgetcwd((char *)cwd
);
537 /* built-in 'eval' handler */
538 static int builtin_eval(struct child_prog
*child
)
541 int rcode
= EXIT_SUCCESS
;
543 if (child
->argv
[1]) {
544 str
= make_string(child
->argv
+ 1);
545 parse_string_outer(str
, FLAG_EXIT_FROM_LOOP
|
546 FLAG_PARSE_SEMICOLON
);
548 rcode
= last_return_code
;
553 /* built-in 'cd <path>' handler */
554 static int builtin_cd(struct child_prog
*child
)
557 if (child
->argv
[1] == NULL
)
558 newdir
= getenv("HOME");
560 newdir
= child
->argv
[1];
562 printf("cd: %s: %s\n", newdir
, strerror(errno
));
569 /* built-in 'env' handler */
570 static int builtin_env(struct child_prog
*dummy
)
573 if (e
== NULL
) return EXIT_FAILURE
;
580 /* built-in 'exec' handler */
581 static int builtin_exec(struct child_prog
*child
)
583 if (child
->argv
[1] == NULL
)
584 return EXIT_SUCCESS
; /* Really? */
590 /* built-in 'exit' handler */
591 static int builtin_exit(struct child_prog
*child
)
593 if (child
->argv
[1] == NULL
)
594 exit(last_return_code
);
595 exit (atoi(child
->argv
[1]));
598 /* built-in 'export VAR=value' handler */
599 static int builtin_export(struct child_prog
*child
)
602 char *name
= child
->argv
[1];
605 return (builtin_env(child
));
611 char *value
= strchr(name
, '=');
615 /* They are exporting something without an =VALUE */
617 value
= get_local_var(name
);
619 size_t ln
= strlen(name
);
621 tmp
= realloc(name
, ln
+strlen(value
)+2);
625 sprintf(tmp
+ln
, "=%s", value
);
629 /* bash does not return an error when trying to export
630 * an undefined variable. Do likewise. */
636 perror_msg("export");
638 res
= set_local_var(name
, 1);
645 /* built-in 'fg' and 'bg' handler */
646 static int builtin_fg_bg(struct child_prog
*child
)
649 struct pipe
*pi
=NULL
;
653 /* If they gave us no args, assume they want the last backgrounded task */
654 if (!child
->argv
[1]) {
655 for (pi
= job_list
; pi
; pi
= pi
->next
) {
656 if (pi
->jobid
== last_jobid
) {
661 error_msg("%s: no current job", child
->argv
[0]);
665 if (sscanf(child
->argv
[1], "%%%d", &jobnum
) != 1) {
666 error_msg("%s: bad argument '%s'", child
->argv
[0], child
->argv
[1]);
669 for (pi
= job_list
; pi
; pi
= pi
->next
) {
670 if (pi
->jobid
== jobnum
) {
675 error_msg("%s: %d: no such job", child
->argv
[0], jobnum
);
680 if (*child
->argv
[0] == 'f') {
681 /* Put the job into the foreground. */
682 tcsetpgrp(shell_terminal
, pi
->pgrp
);
685 /* Restart the processes in the job */
686 for (i
= 0; i
< pi
->num_progs
; i
++)
687 pi
->progs
[i
].is_stopped
= 0;
689 if ( (i
=kill(- pi
->pgrp
, SIGCONT
)) < 0) {
693 perror_msg("kill (SIGCONT)");
697 pi
->stopped_progs
= 0;
701 /* built-in 'help' handler */
702 static int builtin_help(struct child_prog
*dummy
)
704 struct built_in_command
*x
;
706 printf("\nBuilt-in commands:\n");
707 printf("-------------------\n");
708 for (x
= bltins
; x
->cmd
; x
++) {
711 printf("%s\t%s\n", x
->cmd
, x
->descr
);
717 /* built-in 'jobs' handler */
718 static int builtin_jobs(struct child_prog
*child
)
723 for (job
= job_list
; job
; job
= job
->next
) {
724 if (job
->running_progs
== job
->stopped_progs
)
725 status_string
= "Stopped";
727 status_string
= "Running";
729 printf(JOB_STATUS_FORMAT
, job
->jobid
, status_string
, job
->text
);
735 /* built-in 'pwd' handler */
736 static int builtin_pwd(struct child_prog
*dummy
)
742 /* built-in 'read VAR' handler */
743 static int builtin_read(struct child_prog
*child
)
747 if (child
->argv
[1]) {
751 string
[0] = 0; /* In case stdin has only EOF */
753 fgets(string
, sizeof(string
), stdin
);
755 var
= malloc(strlen(child
->argv
[1])+strlen(string
)+2);
757 sprintf(var
, "%s=%s", child
->argv
[1], string
);
758 res
= set_local_var(var
, 0);
762 fprintf(stderr
, "read: %m\n");
763 free(var
); /* So not move up to avoid breaking errno */
766 do res
=getchar(); while(res
!='\n' && res
!=EOF
);
771 /* built-in 'set VAR=value' handler */
772 static int builtin_set(struct child_prog
*child
)
774 char *temp
= child
->argv
[1];
778 for(e
= top_vars
; e
; e
=e
->next
)
779 printf("%s=%s\n", e
->name
, e
->value
);
781 set_local_var(temp
, 0);
787 /* Built-in 'shift' handler */
788 static int builtin_shift(struct child_prog
*child
)
791 if (child
->argv
[1]) {
792 n
=atoi(child
->argv
[1]);
794 if (n
>=0 && n
<global_argc
) {
795 /* XXX This probably breaks $0 */
804 /* Built-in '.' handler (read-in and execute commands from file) */
805 static int builtin_source(struct child_prog
*child
)
810 if (child
->argv
[1] == NULL
)
813 /* XXX search through $PATH is missing */
814 input
= fopen(child
->argv
[1], "r");
816 error_msg("Couldn't open file '%s'", child
->argv
[1]);
820 /* Now run the file */
821 /* XXX argv and argc are broken; need to save old global_argv
822 * (pointer only is OK!) on this stack frame,
823 * set global_argv=child->argv+1, recurse, and restore. */
824 mark_open(fileno(input
));
825 status
= parse_file_outer(input
);
826 mark_closed(fileno(input
));
831 static int builtin_umask(struct child_prog
*child
)
834 const char *arg
= child
->argv
[1];
837 new_umask
=strtoul(arg
, &end
, 8);
838 if (*end
!='\0' || end
== arg
) {
842 printf("%.3o\n", (unsigned int) (new_umask
=umask(0)));
848 /* built-in 'unset VAR' handler */
849 static int builtin_unset(struct child_prog
*child
)
851 /* bash returned already true */
852 unset_local_var(child
->argv
[1]);
856 static int builtin_not_written(struct child_prog
*child
)
858 printf("builtin_%s not written\n",child
->argv
[0]);
863 static int b_check_space(o_string
*o
, int len
)
865 /* It would be easy to drop a more restrictive policy
866 * in here, such as setting a maximum string length */
867 if (o
->length
+ len
> o
->maxlen
) {
868 char *old_data
= o
->data
;
869 /* assert (data == NULL || o->maxlen != 0); */
870 o
->maxlen
+= max(2*len
, B_CHUNK
);
871 o
->data
= realloc(o
->data
, 1 + o
->maxlen
);
872 if (o
->data
== NULL
) {
876 return o
->data
== NULL
;
879 static int b_addchr(o_string
*o
, int ch
)
881 debug_printf("b_addchr: %c %d %p\n", ch
, o
->length
, o
);
882 if (b_check_space(o
, 1)) return B_NOSPAC
;
883 o
->data
[o
->length
] = ch
;
885 o
->data
[o
->length
] = '\0';
889 static void b_reset(o_string
*o
)
893 if (o
->data
!= NULL
) *o
->data
= '\0';
896 static void b_free(o_string
*o
)
904 /* My analysis of quoting semantics tells me that state information
905 * is associated with a destination, not a source.
907 static int b_addqchr(o_string
*o
, int ch
, int quote
)
909 if (quote
&& strchr("*?[\\",ch
)) {
911 rc
= b_addchr(o
, '\\');
914 return b_addchr(o
, ch
);
918 static int b_adduint(o_string
*o
, unsigned int i
)
921 char *p
= simple_itoa(i
);
922 /* no escape checking necessary */
923 do r
=b_addchr(o
, *p
++); while (r
==0 && *p
);
928 static int static_get(struct in_str
*i
)
931 if (ch
=='\0') return EOF
;
935 static int static_peek(struct in_str
*i
)
941 static inline void cmdedit_set_initial_prompt(void)
943 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
952 static inline void setup_prompt_string(int promptmode
, char **prompt_str
)
954 debug_printf("setup_prompt_string %d ",promptmode
);
955 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
956 /* Set up the prompt */
957 if (promptmode
== 1) {
959 PS1
=xmalloc(strlen(cwd
)+4);
960 sprintf(PS1
, "%s %s", cwd
, ( geteuid() != 0 ) ? "$ ":"# ");
966 *prompt_str
= (promptmode
==1)? PS1
: PS2
;
968 debug_printf("result %s\n",*prompt_str
);
972 static void get_user_input(struct in_str
*i
)
976 static char the_command
[BUFSIZ
];
978 setup_prompt_string(i
->promptmode
, &prompt_str
);
979 #ifdef CONFIG_FEATURE_COMMAND_EDITING
981 ** enable command line editing only while a command line
982 ** is actually being read; otherwise, we'll end up bequeathing
983 ** atexit() handlers and other unwanted stuff to our
984 ** child processes (rob@sysgo.de)
986 cmdedit_read_input(prompt_str
, the_command
);
988 fputs(prompt_str
, stdout
);
990 the_command
[0]=fgetc(i
->file
);
997 static char the_command
[CONFIG_SYS_CBSIZE
];
999 #ifdef CONFIG_BOOT_RETRY_TIME
1000 # ifndef CONFIG_RESET_TO_RETRY
1001 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1003 reset_cmd_timeout();
1006 if (i
->promptmode
== 1) {
1007 n
= readline(CONFIG_SYS_PROMPT
);
1009 n
= readline(CONFIG_SYS_PROMPT_HUSH_PS2
);
1011 #ifdef CONFIG_BOOT_RETRY_TIME
1013 puts("\nTimeout waiting for command\n");
1014 # ifdef CONFIG_RESET_TO_RETRY
1015 do_reset(NULL
, 0, 0, NULL
);
1017 # error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1025 n
= strlen(console_buffer
);
1026 console_buffer
[n
] = '\n';
1027 console_buffer
[n
+1]= '\0';
1028 if (had_ctrlc()) flag_repeat
= 0;
1031 if (i
->promptmode
== 1) {
1032 if (console_buffer
[0] == '\n'&& flag_repeat
== 0) {
1033 strcpy(the_command
,console_buffer
);
1036 if (console_buffer
[0] != '\n') {
1037 strcpy(the_command
,console_buffer
);
1047 if (console_buffer
[0] != '\n') {
1048 if (strlen(the_command
) + strlen(console_buffer
)
1049 < CONFIG_SYS_CBSIZE
) {
1050 n
= strlen(the_command
);
1051 the_command
[n
-1] = ' ';
1052 strcpy(&the_command
[n
],console_buffer
);
1055 the_command
[0] = '\n';
1056 the_command
[1] = '\0';
1060 if (i
->__promptme
== 0) {
1061 the_command
[0] = '\n';
1062 the_command
[1] = '\0';
1064 i
->p
= console_buffer
;
1069 /* This is the magic location that prints prompts
1070 * and gets data back from the user */
1071 static int file_get(struct in_str
*i
)
1076 /* If there is data waiting, eat it up */
1077 if (i
->p
&& *i
->p
) {
1080 /* need to double check i->file because we might be doing something
1081 * more complicated by now, like sourcing or substituting. */
1083 if (i
->__promptme
&& interactive
&& i
->file
== stdin
) {
1084 while(! i
->p
|| (interactive
&& strlen(i
->p
)==0) ) {
1086 while(! i
->p
|| strlen(i
->p
)==0 ) {
1094 if (i
->p
&& *i
->p
) {
1099 ch
= fgetc(i
->file
);
1103 debug_printf("b_getch: got a %d\n", ch
);
1106 if (ch
== '\n') i
->__promptme
=1;
1111 /* All the callers guarantee this routine will never be
1112 * used right after a newline, so prompting is not needed.
1114 static int file_peek(struct in_str
*i
)
1117 if (i
->p
&& *i
->p
) {
1122 i
->peek_buf
[0] = fgetc(i
->file
);
1123 i
->peek_buf
[1] = '\0';
1125 debug_printf("b_peek: got a %d\n", *i
->p
);
1132 static void setup_file_in_str(struct in_str
*i
, FILE *f
)
1134 static void setup_file_in_str(struct in_str
*i
)
1137 i
->peek
= file_peek
;
1147 static void setup_string_in_str(struct in_str
*i
, const char *s
)
1149 i
->peek
= static_peek
;
1150 i
->get
= static_get
;
1157 static void mark_open(int fd
)
1159 struct close_me
*new = xmalloc(sizeof(struct close_me
));
1161 new->next
= close_me_head
;
1162 close_me_head
= new;
1165 static void mark_closed(int fd
)
1167 struct close_me
*tmp
;
1168 if (close_me_head
== NULL
|| close_me_head
->fd
!= fd
)
1169 error_msg_and_die("corrupt close_me");
1170 tmp
= close_me_head
;
1171 close_me_head
= close_me_head
->next
;
1175 static void close_all(void)
1178 for (c
=close_me_head
; c
; c
=c
->next
) {
1181 close_me_head
= NULL
;
1184 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1185 * and stderr if they are redirected. */
1186 static int setup_redirects(struct child_prog
*prog
, int squirrel
[])
1189 struct redir_struct
*redir
;
1191 for (redir
=prog
->redirects
; redir
; redir
=redir
->next
) {
1192 if (redir
->dup
== -1 && redir
->word
.gl_pathv
== NULL
) {
1193 /* something went wrong in the parse. Pretend it didn't happen */
1196 if (redir
->dup
== -1) {
1197 mode
=redir_table
[redir
->type
].mode
;
1198 openfd
= open(redir
->word
.gl_pathv
[0], mode
, 0666);
1200 /* this could get lost if stderr has been redirected, but
1201 bash and ash both lose it as well (though zsh doesn't!) */
1202 perror_msg("error opening %s", redir
->word
.gl_pathv
[0]);
1206 openfd
= redir
->dup
;
1209 if (openfd
!= redir
->fd
) {
1210 if (squirrel
&& redir
->fd
< 3) {
1211 squirrel
[redir
->fd
] = dup(redir
->fd
);
1216 dup2(openfd
, redir
->fd
);
1217 if (redir
->dup
== -1)
1225 static void restore_redirects(int squirrel
[])
1228 for (i
=0; i
<3; i
++) {
1231 /* No error checking. I sure wouldn't know what
1232 * to do with an error if I found one! */
1240 /* XXX no exit() here. If you don't exec, use _exit instead.
1241 * The at_exit handlers apparently confuse the calling process,
1242 * in particular stdin handling. Not sure why? */
1243 static void pseudo_exec(struct child_prog
*child
)
1247 struct built_in_command
*x
;
1249 for (i
=0; is_assignment(child
->argv
[i
]); i
++) {
1250 debug_printf("pid %d environment modification: %s\n",getpid(),child
->argv
[i
]);
1251 p
= insert_var_value(child
->argv
[i
]);
1253 if (p
!= child
->argv
[i
]) free(p
);
1255 child
->argv
+=i
; /* XXX this hack isn't so horrible, since we are about
1256 to exit, and therefore don't need to keep data
1257 structures consistent for free() use. */
1258 /* If a variable is assigned in a forest, and nobody listens,
1259 * was it ever really set?
1261 if (child
->argv
[0] == NULL
) {
1262 _exit(EXIT_SUCCESS
);
1266 * Check if the command matches any of the builtins.
1267 * Depending on context, this might be redundant. But it's
1268 * easier to waste a few CPU cycles than it is to figure out
1269 * if this is one of those cases.
1271 for (x
= bltins
; x
->cmd
; x
++) {
1272 if (strcmp(child
->argv
[0], x
->cmd
) == 0 ) {
1273 debug_printf("builtin exec %s\n", child
->argv
[0]);
1274 rcode
= x
->function(child
);
1280 /* Check if the command matches any busybox internal commands
1282 * FIXME: This feature is not 100% safe, since
1283 * BusyBox is not fully reentrant, so we have no guarantee the things
1284 * from the .bss are still zeroed, or that things from .data are still
1285 * at their defaults. We could exec ourself from /proc/self/exe, but I
1286 * really dislike relying on /proc for things. We could exec ourself
1287 * from global_argv[0], but if we are in a chroot, we may not be able
1288 * to find ourself... */
1289 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1292 char** argv_l
=child
->argv
;
1293 char *name
= child
->argv
[0];
1295 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1296 /* Following discussions from November 2000 on the busybox mailing
1297 * list, the default configuration, (without
1298 * get_last_path_component()) lets the user force use of an
1299 * external command by specifying the full (with slashes) filename.
1300 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1301 * _aways_ override external commands, so if you want to run
1302 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1303 * filesystem and is _not_ busybox. Some systems may want this,
1305 name
= get_last_path_component(name
);
1307 /* Count argc for use in a second... */
1308 for(argc_l
=0;*argv_l
!=NULL
; argv_l
++, argc_l
++);
1310 debug_printf("running applet %s\n", name
);
1311 run_applet_by_name(name
, argc_l
, child
->argv
);
1314 debug_printf("exec of %s\n",child
->argv
[0]);
1315 execvp(child
->argv
[0],child
->argv
);
1316 perror_msg("couldn't exec: %s",child
->argv
[0]);
1318 } else if (child
->group
) {
1319 debug_printf("runtime nesting to group\n");
1320 interactive
=0; /* crucial!!!! */
1321 rcode
= run_list_real(child
->group
);
1322 /* OK to leak memory by not calling free_pipe_list,
1323 * since this process is about to exit */
1326 /* Can happen. See what bash does with ">foo" by itself. */
1327 debug_printf("trying to pseudo_exec null command\n");
1328 _exit(EXIT_SUCCESS
);
1332 static void insert_bg_job(struct pipe
*pi
)
1334 struct pipe
*thejob
;
1336 /* Linear search for the ID of the job to use */
1338 for (thejob
= job_list
; thejob
; thejob
= thejob
->next
)
1339 if (thejob
->jobid
>= pi
->jobid
)
1340 pi
->jobid
= thejob
->jobid
+ 1;
1342 /* add thejob to the list of running jobs */
1344 thejob
= job_list
= xmalloc(sizeof(*thejob
));
1346 for (thejob
= job_list
; thejob
->next
; thejob
= thejob
->next
) /* nothing */;
1347 thejob
->next
= xmalloc(sizeof(*thejob
));
1348 thejob
= thejob
->next
;
1351 /* physically copy the struct job */
1352 memcpy(thejob
, pi
, sizeof(struct pipe
));
1353 thejob
->next
= NULL
;
1354 thejob
->running_progs
= thejob
->num_progs
;
1355 thejob
->stopped_progs
= 0;
1356 thejob
->text
= xmalloc(BUFSIZ
); /* cmdedit buffer size */
1358 /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1360 char *bar
=thejob
->text
;
1361 char **foo
=pi
->progs
[0].argv
;
1362 while(foo
&& *foo
) {
1363 bar
+= sprintf(bar
, "%s ", *foo
++);
1367 /* we don't wait for background thejobs to return -- append it
1368 to the list of backgrounded thejobs and leave it alone */
1369 printf("[%d] %d\n", thejob
->jobid
, thejob
->progs
[0].pid
);
1370 last_bg_pid
= thejob
->progs
[0].pid
;
1371 last_jobid
= thejob
->jobid
;
1374 /* remove a backgrounded job */
1375 static void remove_bg_job(struct pipe
*pi
)
1377 struct pipe
*prev_pipe
;
1379 if (pi
== job_list
) {
1380 job_list
= pi
->next
;
1382 prev_pipe
= job_list
;
1383 while (prev_pipe
->next
!= pi
)
1384 prev_pipe
= prev_pipe
->next
;
1385 prev_pipe
->next
= pi
->next
;
1388 last_jobid
= job_list
->jobid
;
1392 pi
->stopped_progs
= 0;
1397 /* Checks to see if any processes have exited -- if they
1398 have, figure out why and see if a job has completed */
1399 static int checkjobs(struct pipe
* fg_pipe
)
1407 attributes
= WUNTRACED
;
1408 if (fg_pipe
==NULL
) {
1409 attributes
|= WNOHANG
;
1412 while ((childpid
= waitpid(-1, &status
, attributes
)) > 0) {
1415 for (i
=0; i
< fg_pipe
->num_progs
; i
++) {
1416 if (fg_pipe
->progs
[i
].pid
== childpid
) {
1417 if (i
==fg_pipe
->num_progs
-1)
1418 rcode
=WEXITSTATUS(status
);
1419 (fg_pipe
->num_progs
)--;
1425 for (pi
= job_list
; pi
; pi
= pi
->next
) {
1427 while (prognum
< pi
->num_progs
&& pi
->progs
[prognum
].pid
!= childpid
) {
1430 if (prognum
< pi
->num_progs
)
1435 debug_printf("checkjobs: pid %d was not in our list!\n", childpid
);
1439 if (WIFEXITED(status
) || WIFSIGNALED(status
)) {
1441 pi
->running_progs
--;
1442 pi
->progs
[prognum
].pid
= 0;
1444 if (!pi
->running_progs
) {
1445 printf(JOB_STATUS_FORMAT
, pi
->jobid
, "Done", pi
->text
);
1450 pi
->stopped_progs
++;
1451 pi
->progs
[prognum
].is_stopped
= 1;
1454 /* Printing this stuff is a pain, since it tends to
1455 * overwrite the prompt an inconveinient moments. So
1457 if (pi
->stopped_progs
== pi
->num_progs
) {
1458 printf("\n"JOB_STATUS_FORMAT
, pi
->jobid
, "Stopped", pi
->text
);
1464 if (childpid
== -1 && errno
!= ECHILD
)
1465 perror_msg("waitpid");
1467 /* move the shell to the foreground */
1468 /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1469 /* perror_msg("tcsetpgrp-2"); */
1473 /* Figure out our controlling tty, checking in order stderr,
1474 * stdin, and stdout. If check_pgrp is set, also check that
1475 * we belong to the foreground process group associated with
1476 * that tty. The value of shell_terminal is needed in order to call
1477 * tcsetpgrp(shell_terminal, ...); */
1478 void controlling_tty(int check_pgrp
)
1482 if ((curpgrp
= tcgetpgrp(shell_terminal
= 2)) < 0
1483 && (curpgrp
= tcgetpgrp(shell_terminal
= 0)) < 0
1484 && (curpgrp
= tcgetpgrp(shell_terminal
= 1)) < 0)
1485 goto shell_terminal_error
;
1487 if (check_pgrp
&& curpgrp
!= getpgid(0))
1488 goto shell_terminal_error
;
1492 shell_terminal_error
:
1493 shell_terminal
= -1;
1498 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1499 * to finish. See checkjobs().
1501 * return code is normally -1, when the caller has to wait for children
1502 * to finish to determine the exit status of the pipe. If the pipe
1503 * is a simple builtin command, however, the action is done by the
1504 * time run_pipe_real returns, and the exit code is provided as the
1507 * The input of the pipe is always stdin, the output is always
1508 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1509 * because it tries to avoid running the command substitution in
1510 * subshell, when that is in fact necessary. The subshell process
1511 * now has its stdout directed to the input of the appropriate pipe,
1512 * so this routine is noticeably simpler.
1514 static int run_pipe_real(struct pipe
*pi
)
1518 int nextin
, nextout
;
1519 int pipefds
[2]; /* pipefds[0] is for reading */
1520 struct child_prog
*child
;
1521 struct built_in_command
*x
;
1524 /* Avoid longjmp clobbering */
1532 int flag
= do_repeat
? CMD_FLAG_REPEAT
: 0;
1533 struct child_prog
*child
;
1536 /* Avoid longjmp clobbering */
1541 #endif /* __U_BOOT__ */
1548 /* Check if this is a simple builtin (not part of a pipe).
1549 * Builtins within pipes have to fork anyway, and are handled in
1550 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1552 if (pi
->num_progs
== 1) child
= & (pi
->progs
[0]);
1554 if (pi
->num_progs
== 1 && child
->group
&& child
->subshell
== 0) {
1555 int squirrel
[] = {-1, -1, -1};
1557 debug_printf("non-subshell grouping\n");
1558 setup_redirects(child
, squirrel
);
1559 /* XXX could we merge code with following builtin case,
1560 * by creating a pseudo builtin that calls run_list_real? */
1561 rcode
= run_list_real(child
->group
);
1562 restore_redirects(squirrel
);
1564 if (pi
->num_progs
== 1 && child
->group
) {
1566 debug_printf("non-subshell grouping\n");
1567 rcode
= run_list_real(child
->group
);
1570 } else if (pi
->num_progs
== 1 && pi
->progs
[0].argv
!= NULL
) {
1571 for (i
=0; is_assignment(child
->argv
[i
]); i
++) { /* nothing */ }
1572 if (i
!=0 && child
->argv
[i
]==NULL
) {
1573 /* assignments, but no command: set the local environment */
1574 for (i
=0; child
->argv
[i
]!=NULL
; i
++) {
1576 /* Ok, this case is tricky. We have to decide if this is a
1577 * local variable, or an already exported variable. If it is
1578 * already exported, we have to export the new value. If it is
1579 * not exported, we need only set this as a local variable.
1580 * This junk is all to decide whether or not to export this
1584 name
= xstrdup(child
->argv
[i
]);
1585 debug_printf("Local environment set: %s\n", name
);
1586 value
= strchr(name
, '=');
1590 if ( get_local_var(name
)) {
1595 p
= insert_var_value(child
->argv
[i
]);
1596 set_local_var(p
, export_me
);
1597 if (p
!= child
->argv
[i
]) free(p
);
1599 return EXIT_SUCCESS
; /* don't worry about errors in set_local_var() yet */
1601 for (i
= 0; is_assignment(child
->argv
[i
]); i
++) {
1602 p
= insert_var_value(child
->argv
[i
]);
1606 set_local_var(p
, 0);
1608 if (p
!= child
->argv
[i
]) {
1616 str
= make_string((child
->argv
+ i
));
1617 parse_string_outer(str
, FLAG_EXIT_FROM_LOOP
| FLAG_REPARSING
);
1619 return last_return_code
;
1622 for (x
= bltins
; x
->cmd
; x
++) {
1623 if (strcmp(child
->argv
[i
], x
->cmd
) == 0 ) {
1624 int squirrel
[] = {-1, -1, -1};
1626 if (x
->function
== builtin_exec
&& child
->argv
[i
+1]==NULL
) {
1627 debug_printf("magic exec\n");
1628 setup_redirects(child
,NULL
);
1629 return EXIT_SUCCESS
;
1631 debug_printf("builtin inline %s\n", child
->argv
[0]);
1632 /* XXX setup_redirects acts on file descriptors, not FILEs.
1633 * This is perfect for work that comes after exec().
1634 * Is it really safe for inline use? Experimentally,
1635 * things seem to work with glibc. */
1636 setup_redirects(child
, squirrel
);
1638 child
->argv
+= i
; /* XXX horrible hack */
1639 rcode
= x
->function(child
);
1640 /* XXX restore hack so free() can work right */
1642 restore_redirects(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 "
1652 "'run' command\n", child
->argv
[i
]);
1655 /* Process the command */
1656 return cmd_process(flag
, child
->argc
, child
->argv
,
1657 &flag_repeat
, NULL
);
1662 for (i
= 0; i
< pi
->num_progs
; i
++) {
1663 child
= & (pi
->progs
[i
]);
1665 /* pipes are inserted between pairs of commands */
1666 if ((i
+ 1) < pi
->num_progs
) {
1667 if (pipe(pipefds
)<0) perror_msg_and_die("pipe");
1668 nextout
= pipefds
[1];
1674 /* XXX test for failed fork()? */
1675 if (!(child
->pid
= fork())) {
1676 /* Set the handling for job control signals back to the default. */
1677 signal(SIGINT
, SIG_DFL
);
1678 signal(SIGQUIT
, SIG_DFL
);
1679 signal(SIGTERM
, SIG_DFL
);
1680 signal(SIGTSTP
, SIG_DFL
);
1681 signal(SIGTTIN
, SIG_DFL
);
1682 signal(SIGTTOU
, SIG_DFL
);
1683 signal(SIGCHLD
, SIG_DFL
);
1695 if (pipefds
[0]!=-1) {
1696 close(pipefds
[0]); /* opposite end of our output pipe */
1699 /* Like bash, explicit redirects override pipes,
1700 * and the pipe fd is available for dup'ing. */
1701 setup_redirects(child
,NULL
);
1703 if (interactive
&& pi
->followup
!=PIPE_BG
) {
1704 /* If we (the child) win the race, put ourselves in the process
1705 * group whose leader is the first process in this pipe. */
1707 pi
->pgrp
= getpid();
1709 if (setpgid(0, pi
->pgrp
) == 0) {
1710 tcsetpgrp(2, pi
->pgrp
);
1718 /* put our child in the process group whose leader is the
1719 first process in this pipe */
1721 pi
->pgrp
= child
->pid
;
1723 /* Don't check for errors. The child may be dead already,
1724 * in which case setpgid returns error code EACCES. */
1725 setpgid(child
->pid
, pi
->pgrp
);
1732 /* If there isn't another process, nextin is garbage
1733 but it doesn't matter */
1734 nextin
= pipefds
[0];
1740 static int run_list_real(struct pipe
*pi
)
1742 char *save_name
= NULL
;
1744 char **save_list
= NULL
;
1750 int rcode
=0, flag_skip
=1;
1751 int flag_restore
= 0;
1752 int if_code
=0, next_if_code
=0; /* need double-buffer to handle elif */
1753 reserved_style rmode
, skip_more_in_this_rmode
=RES_XXXX
;
1754 /* check syntax for "for" */
1755 for (rpipe
= pi
; rpipe
; rpipe
= rpipe
->next
) {
1756 if ((rpipe
->r_mode
== RES_IN
||
1757 rpipe
->r_mode
== RES_FOR
) &&
1758 (rpipe
->next
== NULL
)) {
1765 if ((rpipe
->r_mode
== RES_IN
&&
1766 (rpipe
->next
->r_mode
== RES_IN
&&
1767 rpipe
->next
->progs
->argv
!= NULL
))||
1768 (rpipe
->r_mode
== RES_FOR
&&
1769 rpipe
->next
->r_mode
!= RES_IN
)) {
1777 for (; pi
; pi
= (flag_restore
!= 0) ? rpipe
: pi
->next
) {
1778 if (pi
->r_mode
== RES_WHILE
|| pi
->r_mode
== RES_UNTIL
||
1779 pi
->r_mode
== RES_FOR
) {
1783 if ((had_ctrlc())) {
1794 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
);
1795 if (rmode
== skip_more_in_this_rmode
&& flag_skip
) {
1796 if (pi
->followup
== PIPE_SEQ
) flag_skip
=0;
1800 skip_more_in_this_rmode
= RES_XXXX
;
1801 if (rmode
== RES_THEN
|| rmode
== RES_ELSE
) if_code
= next_if_code
;
1802 if (rmode
== RES_THEN
&& if_code
) continue;
1803 if (rmode
== RES_ELSE
&& !if_code
) continue;
1804 if (rmode
== RES_ELIF
&& !if_code
) break;
1805 if (rmode
== RES_FOR
&& pi
->num_progs
) {
1807 /* if no variable values after "in" we skip "for" */
1808 if (!pi
->next
->progs
->argv
) continue;
1809 /* create list of variable values */
1810 list
= make_list_in(pi
->next
->progs
->argv
,
1811 pi
->progs
->argv
[0]);
1813 save_name
= pi
->progs
->argv
[0];
1814 pi
->progs
->argv
[0] = NULL
;
1818 free(pi
->progs
->argv
[0]);
1822 pi
->progs
->argv
[0] = save_name
;
1824 pi
->progs
->glob_result
.gl_pathv
[0] =
1829 /* insert new value from list for variable */
1830 if (pi
->progs
->argv
[0])
1831 free(pi
->progs
->argv
[0]);
1832 pi
->progs
->argv
[0] = *list
++;
1834 pi
->progs
->glob_result
.gl_pathv
[0] =
1839 if (rmode
== RES_IN
) continue;
1840 if (rmode
== RES_DO
) {
1841 if (!flag_rep
) continue;
1843 if ((rmode
== RES_DONE
)) {
1850 if (pi
->num_progs
== 0) continue;
1852 save_num_progs
= pi
->num_progs
; /* save number of programs */
1854 rcode
= run_pipe_real(pi
);
1855 debug_printf("run_pipe_real returned %d\n",rcode
);
1858 /* We only ran a builtin: rcode was set by the return value
1859 * of run_pipe_real(), and we don't need to wait for anything. */
1860 } else if (pi
->followup
==PIPE_BG
) {
1861 /* XXX check bash's behavior with nontrivial pipes */
1862 /* XXX compute jobid */
1863 /* XXX what does bash do with attempts to background builtins? */
1865 rcode
= EXIT_SUCCESS
;
1868 /* move the new process group into the foreground */
1869 if (tcsetpgrp(shell_terminal
, pi
->pgrp
) && errno
!= ENOTTY
)
1870 perror_msg("tcsetpgrp-3");
1871 rcode
= checkjobs(pi
);
1872 /* move the shell to the foreground */
1873 if (tcsetpgrp(shell_terminal
, getpgid(0)) && errno
!= ENOTTY
)
1874 perror_msg("tcsetpgrp-4");
1876 rcode
= checkjobs(pi
);
1878 debug_printf("checkjobs returned %d\n",rcode
);
1880 last_return_code
=rcode
;
1883 last_return_code
= -rcode
- 2;
1884 return -2; /* exit */
1886 last_return_code
=(rcode
== 0) ? 0 : 1;
1889 pi
->num_progs
= save_num_progs
; /* restore number of programs */
1891 if ( rmode
== RES_IF
|| rmode
== RES_ELIF
)
1892 next_if_code
=rcode
; /* can be overwritten a number of times */
1893 if (rmode
== RES_WHILE
)
1894 flag_rep
= !last_return_code
;
1895 if (rmode
== RES_UNTIL
)
1896 flag_rep
= last_return_code
;
1897 if ( (rcode
==EXIT_SUCCESS
&& pi
->followup
==PIPE_OR
) ||
1898 (rcode
!=EXIT_SUCCESS
&& pi
->followup
==PIPE_AND
) )
1899 skip_more_in_this_rmode
=rmode
;
1907 /* broken, of course, but OK for testing */
1908 static char *indenter(int i
)
1910 static char blanks
[]=" ";
1911 return &blanks
[sizeof(blanks
)-i
-1];
1914 /* return code is the exit status of the pipe */
1915 static int free_pipe(struct pipe
*pi
, int indent
)
1918 struct child_prog
*child
;
1920 struct redir_struct
*r
, *rnext
;
1922 int a
, i
, ret_code
=0;
1923 char *ind
= indenter(indent
);
1926 if (pi
->stopped_progs
> 0)
1928 final_printf("%s run pipe: (pid %d)\n",ind
,getpid());
1930 for (i
=0; i
<pi
->num_progs
; i
++) {
1931 child
= &pi
->progs
[i
];
1932 final_printf("%s command %d:\n",ind
,i
);
1934 for (a
=0,p
=child
->argv
; *p
; a
++,p
++) {
1935 final_printf("%s argv[%d] = %s\n",ind
,a
,*p
);
1938 globfree(&child
->glob_result
);
1940 for (a
= 0; a
< child
->argc
; a
++) {
1941 free(child
->argv
[a
]);
1947 } else if (child
->group
) {
1949 final_printf("%s begin group (subshell:%d)\n",ind
, child
->subshell
);
1951 ret_code
= free_pipe_list(child
->group
,indent
+3);
1952 final_printf("%s end group\n",ind
);
1954 final_printf("%s (nil)\n",ind
);
1957 for (r
=child
->redirects
; r
; r
=rnext
) {
1958 final_printf("%s redirect %d%s", ind
, r
->fd
, redir_table
[r
->type
].descrip
);
1960 /* guard against the case >$FOO, where foo is unset or blank */
1961 if (r
->word
.gl_pathv
) {
1962 final_printf(" %s\n", *r
->word
.gl_pathv
);
1966 final_printf("&%d\n", r
->dup
);
1971 child
->redirects
=NULL
;
1974 free(pi
->progs
); /* children are an array, they get freed all at once */
1979 static int free_pipe_list(struct pipe
*head
, int indent
)
1981 int rcode
=0; /* if list has no members */
1982 struct pipe
*pi
, *next
;
1983 char *ind
= indenter(indent
);
1984 for (pi
=head
; pi
; pi
=next
) {
1985 final_printf("%s pipe reserved mode %d\n", ind
, pi
->r_mode
);
1986 rcode
= free_pipe(pi
, indent
);
1987 final_printf("%s pipe followup code %d\n", ind
, pi
->followup
);
1995 /* Select which version we will use */
1996 static int run_list(struct pipe
*pi
)
2002 rcode
= run_list_real(pi
);
2006 /* free_pipe_list has the side effect of clearing memory
2007 * In the long run that function can be merged with run_list_real,
2008 * but doing that now would hobble the debugging effort. */
2009 free_pipe_list(pi
,0);
2013 /* The API for glob is arguably broken. This routine pushes a non-matching
2014 * string into the output structure, removing non-backslashed backslashes.
2015 * If someone can prove me wrong, by performing this function within the
2016 * original glob(3) api, feel free to rewrite this routine into oblivion.
2017 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2018 * XXX broken if the last character is '\\', check that before calling.
2021 static int globhack(const char *src
, int flags
, glob_t
*pglob
)
2026 for (cnt
=1, s
=src
; s
&& *s
; s
++) {
2027 if (*s
== '\\') s
++;
2031 if (!dest
) return GLOB_NOSPACE
;
2032 if (!(flags
& GLOB_APPEND
)) {
2033 pglob
->gl_pathv
=NULL
;
2038 pathc
= ++pglob
->gl_pathc
;
2039 pglob
->gl_pathv
= realloc(pglob
->gl_pathv
, (pathc
+1)*sizeof(*pglob
->gl_pathv
));
2040 if (pglob
->gl_pathv
== NULL
) return GLOB_NOSPACE
;
2041 pglob
->gl_pathv
[pathc
-1]=dest
;
2042 pglob
->gl_pathv
[pathc
]=NULL
;
2043 for (s
=src
; s
&& *s
; s
++, dest
++) {
2044 if (*s
== '\\') s
++;
2051 /* XXX broken if the last character is '\\', check that before calling */
2052 static int glob_needed(const char *s
)
2055 if (*s
== '\\') s
++;
2056 if (strchr("*[?",*s
)) return 1;
2062 static void globprint(glob_t
*pglob
)
2065 debug_printf("glob_t at %p:\n", pglob
);
2066 debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
2067 pglob
->gl_pathc
, pglob
->gl_pathv
, pglob
->gl_offs
, pglob
->gl_flags
);
2068 for (i
=0; i
<pglob
->gl_pathc
; i
++)
2069 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i
,
2070 pglob
->gl_pathv
[i
], pglob
->gl_pathv
[i
]);
2074 static int xglob(o_string
*dest
, int flags
, glob_t
*pglob
)
2078 /* short-circuit for null word */
2079 /* we can code this better when the debug_printf's are gone */
2080 if (dest
->length
== 0) {
2081 if (dest
->nonnull
) {
2082 /* bash man page calls this an "explicit" null */
2083 gr
= globhack(dest
->data
, flags
, pglob
);
2084 debug_printf("globhack returned %d\n",gr
);
2088 } else if (glob_needed(dest
->data
)) {
2089 gr
= glob(dest
->data
, flags
, NULL
, pglob
);
2090 debug_printf("glob returned %d\n",gr
);
2091 if (gr
== GLOB_NOMATCH
) {
2092 /* quote removal, or more accurately, backslash removal */
2093 gr
= globhack(dest
->data
, flags
, pglob
);
2094 debug_printf("globhack returned %d\n",gr
);
2097 gr
= globhack(dest
->data
, flags
, pglob
);
2098 debug_printf("globhack returned %d\n",gr
);
2100 if (gr
== GLOB_NOSPACE
)
2101 error_msg_and_die("out of memory during glob");
2102 if (gr
!= 0) { /* GLOB_ABORTED ? */
2103 error_msg("glob(3) error %d",gr
);
2105 /* globprint(glob_target); */
2111 static char *get_dollar_var(char ch
);
2114 /* This is used to get/check local shell variables */
2115 char *get_local_var(const char *s
)
2117 struct variables
*cur
;
2124 return get_dollar_var(s
[1]);
2127 for (cur
= top_vars
; cur
; cur
=cur
->next
)
2128 if(strcmp(cur
->name
, s
)==0)
2133 /* This is used to set local shell variables
2134 flg_export==0 if only local (not exporting) variable
2135 flg_export==1 if "new" exporting environ
2136 flg_export>1 if current startup environ (not call putenv()) */
2137 int set_local_var(const char *s
, int flg_export
)
2141 struct variables
*cur
;
2144 /* might be possible! */
2152 if (getenv(name
) != NULL
) {
2154 "There is a global environment variable with the same name.\n");
2159 /* Assume when we enter this function that we are already in
2160 * NAME=VALUE format. So the first order of business is to
2161 * split 's' on the '=' into 'name' and 'value' */
2162 value
= strchr(name
, '=');
2163 if (value
== NULL
&& ++value
== NULL
) {
2169 for(cur
= top_vars
; cur
; cur
= cur
->next
) {
2170 if(strcmp(cur
->name
, name
)==0)
2175 if(strcmp(cur
->value
, value
)==0) {
2176 if(flg_export
>0 && cur
->flg_export
==0)
2177 cur
->flg_export
=flg_export
;
2181 if(cur
->flg_read_only
) {
2182 error_msg("%s: readonly variable", name
);
2185 if(flg_export
>0 || cur
->flg_export
>1)
2189 cur
->value
= strdup(value
);
2193 cur
= malloc(sizeof(struct variables
));
2197 cur
->name
= strdup(name
);
2198 if (cur
->name
== NULL
) {
2202 struct variables
*bottom
= top_vars
;
2203 cur
->value
= strdup(value
);
2205 cur
->flg_export
= flg_export
;
2206 cur
->flg_read_only
= 0;
2207 while(bottom
->next
) bottom
=bottom
->next
;
2214 if(result
==0 && cur
->flg_export
==1) {
2216 result
= putenv(name
);
2221 if(result
>0) /* equivalent to previous set */
2228 void unset_local_var(const char *name
)
2230 struct variables
*cur
;
2233 for (cur
= top_vars
; cur
; cur
=cur
->next
) {
2234 if(strcmp(cur
->name
, name
)==0)
2238 struct variables
*next
= top_vars
;
2239 if(cur
->flg_read_only
) {
2240 error_msg("%s: readonly variable", name
);
2245 unsetenv(cur
->name
);
2249 while (next
->next
!= cur
)
2251 next
->next
= cur
->next
;
2258 static int is_assignment(const char *s
)
2263 if (!isalpha(*s
)) return 0;
2265 while(isalnum(*s
) || *s
=='_') ++s
;
2270 /* the src parameter allows us to peek forward to a possible &n syntax
2271 * for file descriptor duplication, e.g., "2>&1".
2272 * Return code is 0 normally, 1 if a syntax error is detected in src.
2273 * Resource errors (in xmalloc) cause the process to exit */
2274 static int setup_redirect(struct p_context
*ctx
, int fd
, redir_type style
,
2275 struct in_str
*input
)
2277 struct child_prog
*child
=ctx
->child
;
2278 struct redir_struct
*redir
= child
->redirects
;
2279 struct redir_struct
*last_redir
=NULL
;
2281 /* Create a new redir_struct and drop it onto the end of the linked list */
2286 redir
= xmalloc(sizeof(struct redir_struct
));
2288 redir
->word
.gl_pathv
=NULL
;
2290 last_redir
->next
=redir
;
2292 child
->redirects
=redir
;
2296 redir
->fd
= (fd
==-1) ? redir_table
[style
].default_fd
: fd
;
2298 debug_printf("Redirect type %d%s\n", redir
->fd
, redir_table
[style
].descrip
);
2300 /* Check for a '2>&1' type redirect */
2301 redir
->dup
= redirect_dup_num(input
);
2302 if (redir
->dup
== -2) return 1; /* syntax error */
2303 if (redir
->dup
!= -1) {
2304 /* Erik had a check here that the file descriptor in question
2305 * is legit; I postpone that to "run time"
2306 * A "-" representation of "close me" shows up as a -3 here */
2307 debug_printf("Duplicating redirect '%d>&%d'\n", redir
->fd
, redir
->dup
);
2309 /* We do _not_ try to open the file that src points to,
2310 * since we need to return and let src be expanded first.
2311 * Set ctx->pending_redirect, so we know what to do at the
2312 * end of the next parsed word.
2314 ctx
->pending_redirect
= redir
;
2320 static struct pipe
*new_pipe(void)
2323 pi
= xmalloc(sizeof(struct pipe
));
2327 pi
->followup
= 0; /* invalid */
2328 pi
->r_mode
= RES_NONE
;
2332 static void initialize_context(struct p_context
*ctx
)
2336 ctx
->pending_redirect
=NULL
;
2339 ctx
->list_head
=new_pipe();
2340 ctx
->pipe
=ctx
->list_head
;
2346 done_command(ctx
); /* creates the memory for working child */
2349 /* normal return is 0
2350 * if a reserved word is found, and processed, return 1
2351 * should handle if, then, elif, else, fi, for, while, until, do, done.
2352 * case, function, and select are obnoxious, save those for later.
2354 struct reserved_combo
{
2359 /* Mostly a list of accepted follow-up reserved words.
2360 * FLAG_END means we are done with the sequence, and are ready
2361 * to turn the compound list into a command.
2362 * FLAG_START means the word must start a new compound list.
2364 static struct reserved_combo reserved_list
[] = {
2365 { "if", RES_IF
, FLAG_THEN
| FLAG_START
},
2366 { "then", RES_THEN
, FLAG_ELIF
| FLAG_ELSE
| FLAG_FI
},
2367 { "elif", RES_ELIF
, FLAG_THEN
},
2368 { "else", RES_ELSE
, FLAG_FI
},
2369 { "fi", RES_FI
, FLAG_END
},
2370 { "for", RES_FOR
, FLAG_IN
| FLAG_START
},
2371 { "while", RES_WHILE
, FLAG_DO
| FLAG_START
},
2372 { "until", RES_UNTIL
, FLAG_DO
| FLAG_START
},
2373 { "in", RES_IN
, FLAG_DO
},
2374 { "do", RES_DO
, FLAG_DONE
},
2375 { "done", RES_DONE
, FLAG_END
}
2377 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2379 static int reserved_word(o_string
*dest
, struct p_context
*ctx
)
2381 struct reserved_combo
*r
;
2382 for (r
=reserved_list
;
2383 r
<reserved_list
+NRES
; r
++) {
2384 if (strcmp(dest
->data
, r
->literal
) == 0) {
2385 debug_printf("found reserved word %s, code %d\n",r
->literal
,r
->code
);
2386 if (r
->flag
& FLAG_START
) {
2387 struct p_context
*new = xmalloc(sizeof(struct p_context
));
2388 debug_printf("push stack\n");
2389 if (ctx
->w
== RES_IN
|| ctx
->w
== RES_FOR
) {
2396 *new = *ctx
; /* physical copy */
2397 initialize_context(ctx
);
2399 } else if ( ctx
->w
== RES_NONE
|| ! (ctx
->old_flag
& (1<<r
->code
))) {
2406 ctx
->old_flag
= r
->flag
;
2407 if (ctx
->old_flag
& FLAG_END
) {
2408 struct p_context
*old
;
2409 debug_printf("pop stack\n");
2410 done_pipe(ctx
,PIPE_SEQ
);
2412 old
->child
->group
= ctx
->list_head
;
2414 old
->child
->subshell
= 0;
2416 *ctx
= *old
; /* physical copy */
2426 /* normal return is 0.
2427 * Syntax or xglob errors return 1. */
2428 static int done_word(o_string
*dest
, struct p_context
*ctx
)
2430 struct child_prog
*child
=ctx
->child
;
2432 glob_t
*glob_target
;
2439 debug_printf("done_word: %s %p\n", dest
->data
, child
);
2440 if (dest
->length
== 0 && !dest
->nonnull
) {
2441 debug_printf(" true null, ignored\n");
2445 if (ctx
->pending_redirect
) {
2446 glob_target
= &ctx
->pending_redirect
->word
;
2451 return 1; /* syntax error, groups and arglists don't mix */
2453 if (!child
->argv
&& (ctx
->type
& FLAG_PARSE_SEMICOLON
)) {
2454 debug_printf("checking %s for reserved-ness\n",dest
->data
);
2455 if (reserved_word(dest
,ctx
)) return ctx
->w
==RES_SNTX
;
2458 glob_target
= &child
->glob_result
;
2459 if (child
->argv
) flags
|= GLOB_APPEND
;
2461 for (cnt
= 1, s
= dest
->data
; s
&& *s
; s
++) {
2462 if (*s
== '\\') s
++;
2467 if ( child
->argv
== NULL
) {
2470 argc
= ++child
->argc
;
2471 child
->argv
= realloc(child
->argv
, (argc
+1)*sizeof(*child
->argv
));
2472 if (child
->argv
== NULL
) return 1;
2473 child
->argv
[argc
-1]=str
;
2474 child
->argv
[argc
]=NULL
;
2475 for (s
= dest
->data
; s
&& *s
; s
++,str
++) {
2476 if (*s
== '\\') s
++;
2483 gr
= xglob(dest
, flags
, glob_target
);
2484 if (gr
!= 0) return 1;
2489 if (ctx
->pending_redirect
) {
2490 ctx
->pending_redirect
=NULL
;
2491 if (glob_target
->gl_pathc
!= 1) {
2492 error_msg("ambiguous redirect");
2496 child
->argv
= glob_target
->gl_pathv
;
2499 if (ctx
->w
== RES_FOR
) {
2500 done_word(dest
,ctx
);
2501 done_pipe(ctx
,PIPE_SEQ
);
2506 /* The only possible error here is out of memory, in which case
2508 static int done_command(struct p_context
*ctx
)
2510 /* The child is really already in the pipe structure, so
2511 * advance the pipe counter and make a new, null child.
2512 * Only real trickiness here is that the uncommitted
2513 * child structure, to which ctx->child points, is not
2514 * counted in pi->num_progs. */
2515 struct pipe
*pi
=ctx
->pipe
;
2516 struct child_prog
*prog
=ctx
->child
;
2518 if (prog
&& prog
->group
== NULL
2519 && prog
->argv
== NULL
2521 && prog
->redirects
== NULL
) {
2525 debug_printf("done_command: skipping null command\n");
2529 debug_printf("done_command: num_progs incremented to %d\n",pi
->num_progs
);
2531 debug_printf("done_command: initializing\n");
2533 pi
->progs
= xrealloc(pi
->progs
, sizeof(*pi
->progs
) * (pi
->num_progs
+1));
2535 prog
= pi
->progs
+ pi
->num_progs
;
2537 prog
->redirects
= NULL
;
2541 prog
->is_stopped
= 0;
2545 prog
->glob_result
.gl_pathv
= NULL
;
2550 prog
->type
= ctx
->type
;
2552 /* but ctx->pipe and ctx->list_head remain unchanged */
2556 static int done_pipe(struct p_context
*ctx
, pipe_style type
)
2559 done_command(ctx
); /* implicit closure of previous command */
2560 debug_printf("done_pipe, type %d\n", type
);
2561 ctx
->pipe
->followup
= type
;
2562 ctx
->pipe
->r_mode
= ctx
->w
;
2564 ctx
->pipe
->next
= new_p
;
2567 done_command(ctx
); /* set up new pipe to accept commands */
2572 /* peek ahead in the in_str to find out if we have a "&n" construct,
2573 * as in "2>&1", that represents duplicating a file descriptor.
2574 * returns either -2 (syntax error), -1 (no &), or the number found.
2576 static int redirect_dup_num(struct in_str
*input
)
2580 if (ch
!= '&') return -1;
2582 b_getch(input
); /* get the & */
2586 return -3; /* "-" represents "close me" */
2588 while (isdigit(ch
)) {
2596 error_msg("ambiguous redirect");
2600 /* If a redirect is immediately preceded by a number, that number is
2601 * supposed to tell which file descriptor to redirect. This routine
2602 * looks for such preceding numbers. In an ideal world this routine
2603 * needs to handle all the following classes of redirects...
2604 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2605 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2606 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2607 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2608 * A -1 output from this program means no valid number was found, so the
2609 * caller should use the appropriate default for this redirection.
2611 static int redirect_opt_num(o_string
*o
)
2615 if (o
->length
==0) return -1;
2616 for(num
=0; num
<o
->length
; num
++) {
2617 if (!isdigit(*(o
->data
+num
))) {
2621 /* reuse num (and save an int) */
2627 FILE *generate_stream_from_list(struct pipe
*head
)
2631 int pid
, channel
[2];
2632 if (pipe(channel
)<0) perror_msg_and_die("pipe");
2635 perror_msg_and_die("fork");
2636 } else if (pid
==0) {
2638 if (channel
[1] != 1) {
2643 #define SURROGATE "surrogate response"
2644 write(1,SURROGATE
,sizeof(SURROGATE
));
2645 _exit(run_list(head
));
2647 _exit(run_list_real(head
)); /* leaks memory */
2650 debug_printf("forked child %d\n",pid
);
2652 pf
= fdopen(channel
[0],"r");
2653 debug_printf("pipe on FILE *%p\n",pf
);
2655 free_pipe_list(head
,0);
2656 pf
=popen("echo surrogate response","r");
2657 debug_printf("started fake pipe on FILE *%p\n",pf
);
2662 /* this version hacked for testing purposes */
2663 /* return code is exit status of the process that is run. */
2664 static int process_command_subs(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
, int subst_end
)
2667 o_string result
=NULL_O_STRING
;
2668 struct p_context inner
;
2670 struct in_str pipe_str
;
2671 initialize_context(&inner
);
2673 /* recursion to generate command */
2674 retcode
= parse_stream(&result
, &inner
, input
, subst_end
);
2675 if (retcode
!= 0) return retcode
; /* syntax error or EOF */
2676 done_word(&result
, &inner
);
2677 done_pipe(&inner
, PIPE_SEQ
);
2680 p
=generate_stream_from_list(inner
.list_head
);
2681 if (p
==NULL
) return 1;
2682 mark_open(fileno(p
));
2683 setup_file_in_str(&pipe_str
, p
);
2685 /* now send results of command back into original context */
2686 retcode
= parse_stream(dest
, ctx
, &pipe_str
, '\0');
2687 /* XXX In case of a syntax error, should we try to kill the child?
2688 * That would be tough to do right, so just read until EOF. */
2690 while (b_getch(&pipe_str
)!=EOF
) { /* discard */ };
2693 debug_printf("done reading from pipe, pclose()ing\n");
2694 /* This is the step that wait()s for the child. Should be pretty
2695 * safe, since we just read an EOF from its stdout. We could try
2696 * to better, by using wait(), and keeping track of background jobs
2697 * at the same time. That would be a lot of work, and contrary
2698 * to the KISS philosophy of this program. */
2699 mark_closed(fileno(p
));
2701 free_pipe_list(inner
.list_head
,0);
2702 debug_printf("pclosed, retcode=%d\n",retcode
);
2703 /* XXX this process fails to trim a single trailing newline */
2707 static int parse_group(o_string
*dest
, struct p_context
*ctx
,
2708 struct in_str
*input
, int ch
)
2711 struct p_context sub
;
2712 struct child_prog
*child
= ctx
->child
;
2715 return 1; /* syntax error, groups and arglists don't mix */
2717 initialize_context(&sub
);
2719 case '(': endch
=')'; child
->subshell
=1; break;
2720 case '{': endch
='}'; break;
2721 default: syntax(); /* really logic error */
2723 rcode
=parse_stream(dest
,&sub
,input
,endch
);
2724 done_word(dest
,&sub
); /* finish off the final word in the subcontext */
2725 done_pipe(&sub
, PIPE_SEQ
); /* and the final command there, too */
2726 child
->group
= sub
.list_head
;
2728 /* child remains "open", available for possible redirects */
2732 /* basically useful version until someone wants to get fancier,
2733 * see the bash man page under "Parameter Expansion" */
2734 static char *lookup_param(char *src
)
2738 char *default_val
= NULL
;
2740 int expand_empty
= 0;
2745 sep
= strchr(src
, ':');
2749 if (*(sep
+ 1) == '-')
2750 default_val
= sep
+2;
2751 if (*(sep
+ 1) == '=') {
2752 default_val
= sep
+2;
2755 if (*(sep
+ 1) == '+') {
2756 default_val
= sep
+2;
2763 p
= get_local_var(src
);
2765 if (!p
|| strlen(p
) == 0) {
2768 char *var
= malloc(strlen(src
)+strlen(default_val
)+2);
2770 sprintf(var
, "%s=%s", src
, default_val
);
2771 set_local_var(var
, 0);
2775 } else if (expand_empty
) {
2786 static char *get_dollar_var(char ch
)
2788 static char buf
[40];
2793 sprintf(buf
, "%u", (unsigned int)last_return_code
);
2802 /* return code: 0 for OK, 1 for syntax error */
2803 static int handle_dollar(o_string
*dest
, struct p_context
*ctx
, struct in_str
*input
)
2813 int ch
= input
->peek(input
); /* first character after the $ */
2814 debug_printf("handle_dollar: ch=%c\n",ch
);
2816 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2818 while(ch
=b_peek(input
),isalnum(ch
) || ch
=='_') {
2822 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2824 } else if (isdigit(ch
)) {
2825 i
= ch
-'0'; /* XXX is $0 special? */
2826 if (i
<global_argc
) {
2827 parse_string(dest
, ctx
, global_argv
[i
]); /* recursion */
2831 } else switch (ch
) {
2834 b_adduint(dest
,getpid());
2838 if (last_bg_pid
> 0) b_adduint(dest
, last_bg_pid
);
2844 b_adduint(dest
,last_return_code
);
2847 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2848 b_addchr(dest
, '$');
2849 b_addchr(dest
, '?');
2850 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2856 b_adduint(dest
,global_argc
? global_argc
-1 : 0);
2861 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2864 /* XXX maybe someone will try to escape the '}' */
2865 while(ch
=b_getch(input
),ch
!=EOF
&& ch
!='}') {
2872 b_addchr(dest
, SPECIAL_VAR_SYMBOL
);
2877 process_command_subs(dest
, ctx
, input
, ')');
2881 for (i
=1; i
<global_argc
; i
++) {
2882 parse_string(dest
, ctx
, global_argv
[i
]);
2883 if (i
+1 < global_argc
) parse_string(dest
, ctx
, sep
);
2889 /* still unhandled, but should be eventually */
2890 error_msg("unhandled syntax: $%c",ch
);
2895 b_addqchr(dest
,'$',dest
->quote
);
2897 /* Eat the character if the flag was set. If the compiler
2898 * is smart enough, we could substitute "b_getch(input);"
2899 * for all the "advance = 1;" above, and also end up with
2900 * a nice size-optimized program. Hah! That'll be the day.
2902 if (advance
) b_getch(input
);
2907 int parse_string(o_string
*dest
, struct p_context
*ctx
, const char *src
)
2910 setup_string_in_str(&foo
, src
);
2911 return parse_stream(dest
, ctx
, &foo
, '\0');
2915 /* return code is 0 for normal exit, 1 for syntax error */
2916 static int parse_stream(o_string
*dest
, struct p_context
*ctx
,
2917 struct in_str
*input
, int end_trigger
)
2922 redir_type redir_style
;
2926 /* Only double-quote state is handled in the state variable dest->quote.
2927 * A single-quote triggers a bypass of the main loop until its mate is
2928 * found. When recursing, quote state is passed in via dest->quote. */
2930 debug_printf("parse_stream, end_trigger=%d\n",end_trigger
);
2931 while ((ch
=b_getch(input
))!=EOF
) {
2934 if (input
->__promptme
== 0) return 1;
2936 next
= (ch
== '\n') ? 0 : b_peek(input
);
2938 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2939 ch
>= ' ' ? ch
: '.', ch
, m
,
2940 dest
->quote
, ctx
->stack
== NULL
? '*' : '.');
2942 if (m
==0 || ((m
==1 || m
==2) && dest
->quote
)) {
2943 b_addqchr(dest
, ch
, dest
->quote
);
2945 if (m
==2) { /* unquoted IFS */
2946 if (done_word(dest
, ctx
)) {
2949 /* If we aren't performing a substitution, treat a newline as a
2950 * command separator. */
2951 if (end_trigger
!= '\0' && ch
=='\n')
2952 done_pipe(ctx
,PIPE_SEQ
);
2954 if (ch
== end_trigger
&& !dest
->quote
&& ctx
->w
==RES_NONE
) {
2955 debug_printf("leaving parse_stream (triggered)\n");
2960 /* Yahoo! Time to run with it! */
2961 done_pipe(ctx
,PIPE_SEQ
);
2962 run_list(ctx
->list_head
);
2963 initialize_context(ctx
);
2966 if (m
!=2) switch (ch
) {
2968 if (dest
->length
== 0 && !dest
->quote
) {
2969 while(ch
=b_peek(input
),ch
!=EOF
&& ch
!='\n') { b_getch(input
); }
2971 b_addqchr(dest
, ch
, dest
->quote
);
2979 b_addqchr(dest
, '\\', dest
->quote
);
2980 b_addqchr(dest
, b_getch(input
), dest
->quote
);
2983 if (handle_dollar(dest
, ctx
, input
)!=0) return 1;
2987 while(ch
=b_getch(input
),ch
!=EOF
&& ch
!='\'') {
2989 if(input
->__promptme
== 0) return 1;
3000 dest
->quote
= !dest
->quote
;
3004 process_command_subs(dest
, ctx
, input
, '`');
3007 redir_fd
= redirect_opt_num(dest
);
3008 done_word(dest
, ctx
);
3009 redir_style
=REDIRECT_OVERWRITE
;
3011 redir_style
=REDIRECT_APPEND
;
3013 } else if (next
== '(') {
3014 syntax(); /* until we support >(list) Process Substitution */
3017 setup_redirect(ctx
, redir_fd
, redir_style
, input
);
3020 redir_fd
= redirect_opt_num(dest
);
3021 done_word(dest
, ctx
);
3022 redir_style
=REDIRECT_INPUT
;
3024 redir_style
=REDIRECT_HEREIS
;
3026 } else if (next
== '>') {
3027 redir_style
=REDIRECT_IO
;
3029 } else if (next
== '(') {
3030 syntax(); /* until we support <(list) Process Substitution */
3033 setup_redirect(ctx
, redir_fd
, redir_style
, input
);
3037 done_word(dest
, ctx
);
3038 done_pipe(ctx
,PIPE_SEQ
);
3041 done_word(dest
, ctx
);
3044 done_pipe(ctx
,PIPE_AND
);
3047 done_pipe(ctx
,PIPE_BG
);
3055 done_word(dest
, ctx
);
3058 done_pipe(ctx
,PIPE_OR
);
3060 /* we could pick up a file descriptor choice here
3061 * with redirect_opt_num(), but bash doesn't do it.
3062 * "echo foo 2| cat" yields "foo 2". */
3074 if (parse_group(dest
, ctx
, input
, ch
)!=0) return 1;
3078 syntax(); /* Proper use of this character caught by end_trigger */
3082 case SUBSTED_VAR_SYMBOL
:
3084 while (ch
= b_getch(input
), ch
!= EOF
&&
3085 ch
!= SUBSTED_VAR_SYMBOL
) {
3086 debug_printf("subst, pass=%d\n", ch
);
3087 if (input
->__promptme
== 0)
3091 debug_printf("subst, term=%d\n", ch
);
3098 syntax(); /* this is really an internal logic error */
3103 /* complain if quote? No, maybe we just finished a command substitution
3104 * that was quoted. Example:
3105 * $ echo "`cat foo` plus more"
3106 * and we just got the EOF generated by the subshell that ran "cat foo"
3107 * The only real complaint is if we got an EOF when end_trigger != '\0',
3108 * that is, we were really supposed to get end_trigger, and never got
3109 * one before the EOF. Can't use the standard "syntax error" return code,
3110 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3111 debug_printf("leaving parse_stream (EOF)\n");
3112 if (end_trigger
!= '\0') return -1;
3116 static void mapset(const unsigned char *set
, int code
)
3118 const unsigned char *s
;
3119 for (s
=set
; *s
; s
++) map
[*s
] = code
;
3122 static void update_ifs_map(void)
3124 /* char *ifs and char map[256] are both globals. */
3125 ifs
= (uchar
*)getenv("IFS");
3126 if (ifs
== NULL
) ifs
=(uchar
*)" \t\n";
3127 /* Precompute a list of 'flow through' behavior so it can be treated
3128 * quickly up front. Computation is necessary because of IFS.
3129 * Special case handling of IFS == " \t\n" is not implemented.
3130 * The map[] array only really needs two bits each, and on most machines
3131 * that would be faster because of the reduced L1 cache footprint.
3133 memset(map
,0,sizeof(map
)); /* most characters flow through always */
3135 mapset((uchar
*)"\\$'\"`", 3); /* never flow through */
3136 mapset((uchar
*)"<>;&|(){}#", 1); /* flow through if quoted */
3139 uchar subst
[2] = {SUBSTED_VAR_SYMBOL
, 0};
3140 mapset(subst
, 3); /* never flow through */
3142 mapset((uchar
*)"\\$'\"", 3); /* never flow through */
3143 mapset((uchar
*)";&|#", 1); /* flow through if quoted */
3145 mapset(ifs
, 2); /* also flow through if quoted */
3148 /* most recursion does not come through here, the exeception is
3149 * from builtin_source() */
3150 static int parse_stream_outer(struct in_str
*inp
, int flag
)
3153 struct p_context ctx
;
3154 o_string temp
=NULL_O_STRING
;
3161 initialize_context(&ctx
);
3163 if (!(flag
& FLAG_PARSE_SEMICOLON
) || (flag
& FLAG_REPARSING
)) mapset((uchar
*)";$&|", 0);
3165 rcode
= parse_stream(&temp
, &ctx
, inp
, '\n');
3167 if (rcode
== 1) flag_repeat
= 0;
3169 if (rcode
!= 1 && ctx
.old_flag
!= 0) {
3175 if (rcode
!= 1 && ctx
.old_flag
== 0) {
3176 done_word(&temp
, &ctx
);
3177 done_pipe(&ctx
,PIPE_SEQ
);
3179 run_list(ctx
.list_head
);
3181 code
= run_list(ctx
.list_head
);
3182 if (code
== -2) { /* exit */
3185 /* XXX hackish way to not allow exit from main loop */
3186 if (inp
->peek
== file_peek
) {
3187 printf("exit not allowed from main input shell.\n");
3196 if (ctx
.old_flag
!= 0) {
3201 if (inp
->__promptme
== 0) printf("<INTERRUPT>\n");
3202 inp
->__promptme
= 1;
3207 free_pipe_list(ctx
.list_head
,0);
3210 } while (rcode
!= -1 && !(flag
& FLAG_EXIT_FROM_LOOP
)); /* loop on syntax errors, return on EOF */
3214 return (code
!= 0) ? 1 : 0;
3215 #endif /* __U_BOOT__ */
3219 static int parse_string_outer(const char *s
, int flag
)
3221 int parse_string_outer(const char *s
, int flag
)
3222 #endif /* __U_BOOT__ */
3224 struct in_str input
;
3230 if (!(p
= strchr(s
, '\n')) || *++p
) {
3231 p
= xmalloc(strlen(s
) + 2);
3234 setup_string_in_str(&input
, p
);
3235 rcode
= parse_stream_outer(&input
, flag
);
3240 setup_string_in_str(&input
, s
);
3241 return parse_stream_outer(&input
, flag
);
3248 static int parse_file_outer(FILE *f
)
3250 int parse_file_outer(void)
3254 struct in_str input
;
3256 setup_file_in_str(&input
, f
);
3258 setup_file_in_str(&input
);
3260 rcode
= parse_stream_outer(&input
, FLAG_PARSE_SEMICOLON
);
3265 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3266 static void u_boot_hush_reloc(void)
3269 struct reserved_combo
*r
;
3271 for (r
=reserved_list
; r
<reserved_list
+NRES
; r
++) {
3272 addr
= (ulong
) (r
->literal
) + gd
->reloc_off
;
3273 r
->literal
= (char *)addr
;
3278 int u_boot_hush_start(void)
3280 if (top_vars
== NULL
) {
3281 top_vars
= malloc(sizeof(struct variables
));
3282 top_vars
->name
= "HUSH_VERSION";
3283 top_vars
->value
= "0.01";
3284 top_vars
->next
= NULL
;
3285 top_vars
->flg_export
= 0;
3286 top_vars
->flg_read_only
= 1;
3287 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3288 u_boot_hush_reloc();
3294 static void *xmalloc(size_t size
)
3298 if (!(p
= malloc(size
))) {
3299 printf("ERROR : memory not allocated\n");
3305 static void *xrealloc(void *ptr
, size_t size
)
3309 if (!(p
= realloc(ptr
, size
))) {
3310 printf("ERROR : memory not allocated\n");
3315 #endif /* __U_BOOT__ */
3318 /* Make sure we have a controlling tty. If we get started under a job
3319 * aware app (like bash for example), make sure we are now in charge so
3320 * we don't fight over who gets the foreground */
3321 static void setup_job_control(void)
3323 static pid_t shell_pgrp
;
3324 /* Loop until we are in the foreground. */
3325 while (tcgetpgrp (shell_terminal
) != (shell_pgrp
= getpgrp ()))
3326 kill (- shell_pgrp
, SIGTTIN
);
3328 /* Ignore interactive and job-control signals. */
3329 signal(SIGINT
, SIG_IGN
);
3330 signal(SIGQUIT
, SIG_IGN
);
3331 signal(SIGTERM
, SIG_IGN
);
3332 signal(SIGTSTP
, SIG_IGN
);
3333 signal(SIGTTIN
, SIG_IGN
);
3334 signal(SIGTTOU
, SIG_IGN
);
3335 signal(SIGCHLD
, SIG_IGN
);
3337 /* Put ourselves in our own process group. */
3339 shell_pgrp
= getpid ();
3340 setpgid (shell_pgrp
, shell_pgrp
);
3342 /* Grab control of the terminal. */
3343 tcsetpgrp(shell_terminal
, shell_pgrp
);
3346 int hush_main(int argc
, char * const *argv
)
3352 /* XXX what should these be while sourcing /etc/profile? */
3356 /* (re?) initialize globals. Sometimes hush_main() ends up calling
3357 * hush_main(), therefore we cannot rely on the BSS to zero out this
3358 * stuff. Reset these to 0 every time. */
3360 /* map[] is taken care of with call to update_ifs_map() */
3363 close_me_head
= NULL
;
3368 /* Initialize some more globals to non-zero values */
3370 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3371 cmdedit_set_initial_prompt();
3377 /* initialize our shell local variables with the values
3378 * currently living in the environment */
3381 set_local_var(*e
, 2); /* without call putenv() */
3384 last_return_code
=EXIT_SUCCESS
;
3387 if (argv
[0] && argv
[0][0] == '-') {
3388 debug_printf("\nsourcing /etc/profile\n");
3389 if ((input
= fopen("/etc/profile", "r")) != NULL
) {
3390 mark_open(fileno(input
));
3391 parse_file_outer(input
);
3392 mark_closed(fileno(input
));
3398 while ((opt
= getopt(argc
, argv
, "c:xif")) > 0) {
3402 global_argv
= argv
+optind
;
3403 global_argc
= argc
-optind
;
3404 opt
= parse_string_outer(optarg
, FLAG_PARSE_SEMICOLON
);
3416 fprintf(stderr
, "Usage: sh [FILE]...\n"
3417 " or: sh -c command [args]...\n\n");
3424 /* A shell is interactive if the `-i' flag was given, or if all of
3425 * the following conditions are met:
3427 * no arguments remaining or the -s flag given
3428 * standard input is a terminal
3429 * standard output is a terminal
3430 * Refer to Posix.2, the description of the `sh' utility. */
3431 if (argv
[optind
]==NULL
&& input
==stdin
&&
3432 isatty(fileno(stdin
)) && isatty(fileno(stdout
))) {
3436 debug_printf("\ninteractive=%d\n", interactive
);
3438 /* Looks like they want an interactive shell */
3439 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3440 printf( "\n\n" BB_BANNER
" hush - the humble shell v0.01 (testing)\n");
3441 printf( "Enter 'help' for a list of built-in commands.\n\n");
3443 setup_job_control();
3446 if (argv
[optind
]==NULL
) {
3447 opt
=parse_file_outer(stdin
);
3451 debug_printf("\nrunning script '%s'\n", argv
[optind
]);
3452 global_argv
= argv
+optind
;
3453 global_argc
= argc
-optind
;
3454 input
= xfopen(argv
[optind
], "r");
3455 opt
= parse_file_outer(input
);
3457 #ifdef CONFIG_FEATURE_CLEAN_UP
3459 if (cwd
&& cwd
!= unknown
)
3462 struct variables
*cur
, *tmp
;
3463 for(cur
= top_vars
; cur
; cur
= tmp
) {
3465 if (!cur
->flg_read_only
) {
3475 return(opt
?opt
:last_return_code
);
3479 static char *insert_var_value(char *inp
)
3481 return insert_var_value_sub(inp
, 0);
3484 static char *insert_var_value_sub(char *inp
, int tag_subst
)
3486 int res_str_len
= 0;
3489 char *p
, *p1
, *res_str
= NULL
;
3491 while ((p
= strchr(inp
, SPECIAL_VAR_SYMBOL
))) {
3492 /* check the beginning of the string for normal charachters */
3494 /* copy any charachters to the result string */
3496 res_str
= xrealloc(res_str
, (res_str_len
+ len
));
3497 strncpy((res_str
+ res_str_len
), inp
, len
);
3501 /* find the ending marker */
3502 p
= strchr(inp
, SPECIAL_VAR_SYMBOL
);
3504 /* look up the value to substitute */
3505 if ((p1
= lookup_param(inp
))) {
3507 len
= res_str_len
+ strlen(p1
) + 2;
3509 len
= res_str_len
+ strlen(p1
);
3510 res_str
= xrealloc(res_str
, (1 + len
));
3513 * copy the variable value to the result
3516 strcpy((res_str
+ res_str_len
+ 1), p1
);
3519 * mark the replaced text to be accepted as
3522 res_str
[res_str_len
] = SUBSTED_VAR_SYMBOL
;
3523 res_str
[res_str_len
+ 1 + strlen(p1
)] =
3527 * copy the variable value to the result
3530 strcpy((res_str
+ res_str_len
), p1
);
3534 *p
= SPECIAL_VAR_SYMBOL
;
3539 res_str
= xrealloc(res_str
, (1 + res_str_len
+ strlen(inp
)));
3540 strcpy((res_str
+ res_str_len
), inp
);
3541 while ((p
= strchr(res_str
, '\n'))) {
3545 return (res_str
== NULL
) ? inp
: res_str
;
3548 static char **make_list_in(char **inp
, char *name
)
3551 int name_len
= strlen(name
);
3556 /* create list of variable values */
3557 list
= xmalloc(sizeof(*list
));
3558 for (i
= 0; inp
[i
]; i
++) {
3559 p3
= insert_var_value(inp
[i
]);
3566 if ((p2
= strchr(p1
, ' '))) {
3572 /* we use n + 2 in realloc for list,because we add
3573 * new element and then we will add NULL element */
3574 list
= xrealloc(list
, sizeof(*list
) * (n
+ 2));
3575 list
[n
] = xmalloc(2 + name_len
+ len
);
3576 strcpy(list
[n
], name
);
3577 strcat(list
[n
], "=");
3578 strncat(list
[n
], p1
, len
);
3579 list
[n
++][name_len
+ len
+ 1] = '\0';
3582 if (p3
!= inp
[i
]) free(p3
);
3588 /* Make new string for parser */
3589 static char * make_string(char ** inp
)
3598 noeval_str
= get_local_var("HUSH_NO_EVAL");
3599 if (noeval_str
!= NULL
&& *noeval_str
!= '0' && *noeval_str
!= '\0')
3601 for (n
= 0; inp
[n
]; n
++) {
3602 p
= insert_var_value_sub(inp
[n
], noeval
);
3603 str
= xrealloc(str
, (len
+ strlen(p
)));
3610 len
= strlen(str
) + 3;
3611 if (p
!= inp
[n
]) free(p
);
3614 *(str
+ len
) = '\n';
3615 *(str
+ len
+ 1) = '\0';
3620 static int do_showvar(cmd_tbl_t
*cmdtp
, int flag
, int argc
,
3621 char * const argv
[])
3625 struct variables
*cur
;
3627 if (argc
== 1) { /* Print all env variables */
3628 for (cur
= top_vars
; cur
; cur
= cur
->next
) {
3629 printf ("%s=%s\n", cur
->name
, cur
->value
);
3631 puts ("\n ** Abort\n");
3637 for (i
= 1; i
< argc
; ++i
) { /* print single env variables */
3638 char *name
= argv
[i
];
3641 for (cur
= top_vars
; cur
; cur
= cur
->next
) {
3642 if(strcmp (cur
->name
, name
) == 0) {
3644 printf ("%s=%s\n", cur
->name
, cur
->value
);
3647 puts ("\n ** Abort\n");
3652 printf ("## Error: \"%s\" not defined\n", name
);
3660 showvar
, CONFIG_SYS_MAXARGS
, 1, do_showvar
,
3661 "print local hushshell variables",
3662 "\n - print values of all hushshell variables\n"
3663 "showvar name ...\n"
3664 " - print value of hushshell variable 'name'"
3668 /****************************************************************************/