source: MondoRescue/trunk/mindi-busybox/shell/hush.c@ 904

Last change on this file since 904 was 821, checked in by Bruno Cornec, 18 years ago

Addition of busybox 1.2.1 as a mindi-busybox new package
This should avoid delivering binary files in mindi not built there (Fedora and Debian are quite serious about that)
File size: 79.5 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
3 * sh.c -- a prototype Bourne shell grammar parser
4 * Intended to follow the original Thompson and Ritchie
5 * "small and simple is beautiful" philosophy, which
6 * incidentally is a good match to today's BusyBox.
7 *
8 * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
9 *
10 * Credits:
11 * The parser routines proper are all original material, first
12 * written Dec 2000 and Jan 2001 by Larry Doolittle. The
13 * execution engine, the builtins, and much of the underlying
14 * support has been adapted from busybox-0.49pre's lash, which is
15 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
16 * written by Erik Andersen <andersen@codepoet.org>. That, in turn,
17 * is based in part on ladsh.c, by Michael K. Johnson and Erik W.
18 * Troan, which they placed in the public domain. I don't know
19 * how much of the Johnson/Troan code has survived the repeated
20 * rewrites.
21 *
22 * Other credits:
23 * simple_itoa() was lifted from boa-0.93.15
24 * b_addchr() derived from similar w_addchar function in glibc-2.2
25 * setup_redirect(), redirect_opt_num(), and big chunks of main()
26 * and many builtins derived from contributions by Erik Andersen
27 * miscellaneous bugfixes from Matt Kraai
28 *
29 * There are two big (and related) architecture differences between
30 * this parser and the lash parser. One is that this version is
31 * actually designed from the ground up to understand nearly all
32 * of the Bourne grammar. The second, consequential change is that
33 * the parser and input reader have been turned inside out. Now,
34 * the parser is in control, and asks for input as needed. The old
35 * way had the input reader in control, and it asked for parsing to
36 * take place as needed. The new way makes it much easier to properly
37 * handle the recursion implicit in the various substitutions, especially
38 * across continuation lines.
39 *
40 * Bash grammar not implemented: (how many of these were in original sh?)
41 * $@ (those sure look like weird quoting rules)
42 * $_
43 * ! negation operator for pipes
44 * &> and >& redirection of stdout+stderr
45 * Brace Expansion
46 * Tilde Expansion
47 * fancy forms of Parameter Expansion
48 * aliases
49 * Arithmetic Expansion
50 * <(list) and >(list) Process Substitution
51 * reserved words: case, esac, select, function
52 * Here Documents ( << word )
53 * Functions
54 * Major bugs:
55 * job handling woefully incomplete and buggy
56 * reserved word execution woefully incomplete and buggy
57 * to-do:
58 * port selected bugfixes from post-0.49 busybox lash - done?
59 * finish implementing reserved words: for, while, until, do, done
60 * change { and } from special chars to reserved words
61 * builtins: break, continue, eval, return, set, trap, ulimit
62 * test magic exec
63 * handle children going into background
64 * clean up recognition of null pipes
65 * check setting of global_argc and global_argv
66 * control-C handling, probably with longjmp
67 * follow IFS rules more precisely, including update semantics
68 * figure out what to do with backslash-newline
69 * explain why we use signal instead of sigaction
70 * propagate syntax errors, die on resource errors?
71 * continuation lines, both explicit and implicit - done?
72 * memory leak finding and plugging - done?
73 * more testing, especially quoting rules and redirection
74 * document how quoting rules not precisely followed for variable assignments
75 * maybe change map[] to use 2-bit entries
76 * (eventually) remove all the printf's
77 *
78 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
79 */
80
81#include "busybox.h"
82#include <ctype.h> /* isalpha, isdigit */
83#include <unistd.h> /* getpid */
84#include <stdlib.h> /* getenv, atoi */
85#include <string.h> /* strchr */
86#include <stdio.h> /* popen etc. */
87#include <glob.h> /* glob, of course */
88#include <stdarg.h> /* va_list */
89#include <errno.h>
90#include <fcntl.h>
91#include <getopt.h> /* should be pretty obvious */
92
93#include <sys/stat.h> /* ulimit */
94#include <sys/types.h>
95#include <sys/wait.h>
96#include <signal.h>
97
98/* #include <dmalloc.h> */
99/* #define DEBUG_SHELL */
100
101#if 1
102#include "cmdedit.h"
103#else
104#define bb_applet_name "hush"
105//#include "standalone.h"
106#define hush_main main
107#undef CONFIG_FEATURE_SH_FANCY_PROMPT
108#define BB_BANNER ""
109#endif
110#define SPECIAL_VAR_SYMBOL 03
111#define FLAG_EXIT_FROM_LOOP 1
112#define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
113#define FLAG_REPARSING (1 << 2) /* >=2nd pass */
114
115typedef enum {
116 REDIRECT_INPUT = 1,
117 REDIRECT_OVERWRITE = 2,
118 REDIRECT_APPEND = 3,
119 REDIRECT_HEREIS = 4,
120 REDIRECT_IO = 5
121} redir_type;
122
123/* The descrip member of this structure is only used to make debugging
124 * output pretty */
125static const struct {int mode; int default_fd; const char *descrip;} redir_table[] = {
126 { 0, 0, "()" },
127 { O_RDONLY, 0, "<" },
128 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
129 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
130 { O_RDONLY, -1, "<<" },
131 { O_RDWR, 1, "<>" }
132};
133
134typedef enum {
135 PIPE_SEQ = 1,
136 PIPE_AND = 2,
137 PIPE_OR = 3,
138 PIPE_BG = 4,
139} pipe_style;
140
141/* might eventually control execution */
142typedef enum {
143 RES_NONE = 0,
144 RES_IF = 1,
145 RES_THEN = 2,
146 RES_ELIF = 3,
147 RES_ELSE = 4,
148 RES_FI = 5,
149 RES_FOR = 6,
150 RES_WHILE = 7,
151 RES_UNTIL = 8,
152 RES_DO = 9,
153 RES_DONE = 10,
154 RES_XXXX = 11,
155 RES_IN = 12,
156 RES_SNTX = 13
157} reserved_style;
158#define FLAG_END (1<<RES_NONE)
159#define FLAG_IF (1<<RES_IF)
160#define FLAG_THEN (1<<RES_THEN)
161#define FLAG_ELIF (1<<RES_ELIF)
162#define FLAG_ELSE (1<<RES_ELSE)
163#define FLAG_FI (1<<RES_FI)
164#define FLAG_FOR (1<<RES_FOR)
165#define FLAG_WHILE (1<<RES_WHILE)
166#define FLAG_UNTIL (1<<RES_UNTIL)
167#define FLAG_DO (1<<RES_DO)
168#define FLAG_DONE (1<<RES_DONE)
169#define FLAG_IN (1<<RES_IN)
170#define FLAG_START (1<<RES_XXXX)
171
172/* This holds pointers to the various results of parsing */
173struct p_context {
174 struct child_prog *child;
175 struct pipe *list_head;
176 struct pipe *pipe;
177 struct redir_struct *pending_redirect;
178 reserved_style w;
179 int old_flag; /* for figuring out valid reserved words */
180 struct p_context *stack;
181 int type; /* define type of parser : ";$" common or special symbol */
182 /* How about quoting status? */
183};
184
185struct redir_struct {
186 redir_type type; /* type of redirection */
187 int fd; /* file descriptor being redirected */
188 int dup; /* -1, or file descriptor being duplicated */
189 struct redir_struct *next; /* pointer to the next redirect in the list */
190 glob_t word; /* *word.gl_pathv is the filename */
191};
192
193struct child_prog {
194 pid_t pid; /* 0 if exited */
195 char **argv; /* program name and arguments */
196 struct pipe *group; /* if non-NULL, first in group or subshell */
197 int subshell; /* flag, non-zero if group must be forked */
198 struct redir_struct *redirects; /* I/O redirections */
199 glob_t glob_result; /* result of parameter globbing */
200 int is_stopped; /* is the program currently running? */
201 struct pipe *family; /* pointer back to the child's parent pipe */
202 int sp; /* number of SPECIAL_VAR_SYMBOL */
203 int type;
204};
205
206struct pipe {
207 int jobid; /* job number */
208 int num_progs; /* total number of programs in job */
209 int running_progs; /* number of programs running */
210 char *text; /* name of job */
211 char *cmdbuf; /* buffer various argv's point into */
212 pid_t pgrp; /* process group ID for the job */
213 struct child_prog *progs; /* array of commands in pipe */
214 struct pipe *next; /* to track background commands */
215 int stopped_progs; /* number of programs alive, but stopped */
216 int job_context; /* bitmask defining current context */
217 pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
218 reserved_style r_mode; /* supports if, for, while, until */
219};
220
221struct close_me {
222 int fd;
223 struct close_me *next;
224};
225
226struct variables {
227 char *name;
228 char *value;
229 int flg_export;
230 int flg_read_only;
231 struct variables *next;
232};
233
234/* globals, connect us to the outside world
235 * the first three support $?, $#, and $1 */
236static char **global_argv;
237static int global_argc;
238static int last_return_code;
239extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
240
241/* "globals" within this file */
242static char *ifs;
243static unsigned char map[256];
244static int fake_mode;
245static int interactive;
246static struct close_me *close_me_head;
247static const char *cwd;
248static struct pipe *job_list;
249static unsigned int last_bg_pid;
250static int last_jobid;
251static unsigned int shell_terminal;
252static char *PS1;
253static char *PS2;
254static struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
255static struct variables *top_vars = &shell_ver;
256
257
258#define B_CHUNK (100)
259#define B_NOSPAC 1
260
261typedef struct {
262 char *data;
263 int length;
264 int maxlen;
265 int quote;
266 int nonnull;
267} o_string;
268#define NULL_O_STRING {NULL,0,0,0,0}
269/* used for initialization:
270 o_string foo = NULL_O_STRING; */
271
272/* I can almost use ordinary FILE *. Is open_memstream() universally
273 * available? Where is it documented? */
274struct in_str {
275 const char *p;
276 char peek_buf[2];
277 int __promptme;
278 int promptmode;
279 FILE *file;
280 int (*get) (struct in_str *);
281 int (*peek) (struct in_str *);
282};
283#define b_getch(input) ((input)->get(input))
284#define b_peek(input) ((input)->peek(input))
285
286#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
287
288struct built_in_command {
289 const char *cmd; /* name */
290 const char *descr; /* description */
291 int (*function) (struct child_prog *); /* function ptr */
292};
293
294/* belongs in busybox.h */
295static inline int max(int a, int b) {
296 return (a>b)?a:b;
297}
298
299/* This should be in utility.c */
300#ifdef DEBUG_SHELL
301static void debug_printf(const char *format, ...)
302{
303 va_list args;
304 va_start(args, format);
305 vfprintf(stderr, format, args);
306 va_end(args);
307}
308#else
309static inline void debug_printf(const char *format ATTRIBUTE_UNUSED, ...) { }
310#endif
311#define final_printf debug_printf
312
313static void __syntax(char *file, int line) {
314 bb_error_msg("syntax error %s:%d", file, line);
315}
316#define syntax() __syntax(__FILE__, __LINE__)
317
318/* Index of subroutines: */
319/* function prototypes for builtins */
320static int builtin_cd(struct child_prog *child);
321static int builtin_env(struct child_prog *child);
322static int builtin_eval(struct child_prog *child);
323static int builtin_exec(struct child_prog *child);
324static int builtin_exit(struct child_prog *child);
325static int builtin_export(struct child_prog *child);
326static int builtin_fg_bg(struct child_prog *child);
327static int builtin_help(struct child_prog *child);
328static int builtin_jobs(struct child_prog *child);
329static int builtin_pwd(struct child_prog *child);
330static int builtin_read(struct child_prog *child);
331static int builtin_set(struct child_prog *child);
332static int builtin_shift(struct child_prog *child);
333static int builtin_source(struct child_prog *child);
334static int builtin_umask(struct child_prog *child);
335static int builtin_unset(struct child_prog *child);
336static int builtin_not_written(struct child_prog *child);
337/* o_string manipulation: */
338static int b_check_space(o_string *o, int len);
339static int b_addchr(o_string *o, int ch);
340static void b_reset(o_string *o);
341static int b_addqchr(o_string *o, int ch, int quote);
342static int b_adduint(o_string *o, unsigned int i);
343/* in_str manipulations: */
344static int static_get(struct in_str *i);
345static int static_peek(struct in_str *i);
346static int file_get(struct in_str *i);
347static int file_peek(struct in_str *i);
348static void setup_file_in_str(struct in_str *i, FILE *f);
349static void setup_string_in_str(struct in_str *i, const char *s);
350/* close_me manipulations: */
351static void mark_open(int fd);
352static void mark_closed(int fd);
353static void close_all(void);
354/* "run" the final data structures: */
355static char *indenter(int i);
356static int free_pipe_list(struct pipe *head, int indent);
357static int free_pipe(struct pipe *pi, int indent);
358/* really run the final data structures: */
359static int setup_redirects(struct child_prog *prog, int squirrel[]);
360static int run_list_real(struct pipe *pi);
361static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN;
362static int run_pipe_real(struct pipe *pi);
363/* extended glob support: */
364static int globhack(const char *src, int flags, glob_t *pglob);
365static int glob_needed(const char *s);
366static int xglob(o_string *dest, int flags, glob_t *pglob);
367/* variable assignment: */
368static int is_assignment(const char *s);
369/* data structure manipulation: */
370static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
371static void initialize_context(struct p_context *ctx);
372static int done_word(o_string *dest, struct p_context *ctx);
373static int done_command(struct p_context *ctx);
374static int done_pipe(struct p_context *ctx, pipe_style type);
375/* primary string parsing: */
376static int redirect_dup_num(struct in_str *input);
377static int redirect_opt_num(o_string *o);
378static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
379static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
380static char *lookup_param(char *src);
381static char *make_string(char **inp);
382static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
383static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
384static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
385/* setup: */
386static int parse_stream_outer(struct in_str *inp, int flag);
387static int parse_string_outer(const char *s, int flag);
388static int parse_file_outer(FILE *f);
389/* job management: */
390static int checkjobs(struct pipe* fg_pipe);
391static void insert_bg_job(struct pipe *pi);
392static void remove_bg_job(struct pipe *pi);
393/* local variable support */
394static char **make_list_in(char **inp, char *name);
395static char *insert_var_value(char *inp);
396static char *get_local_var(const char *var);
397static void unset_local_var(const char *name);
398static int set_local_var(const char *s, int flg_export);
399
400/* Table of built-in functions. They can be forked or not, depending on
401 * context: within pipes, they fork. As simple commands, they do not.
402 * When used in non-forking context, they can change global variables
403 * in the parent shell process. If forked, of course they can not.
404 * For example, 'unset foo | whatever' will parse and run, but foo will
405 * still be set at the end. */
406static const struct built_in_command bltins[] = {
407 {"bg", "Resume a job in the background", builtin_fg_bg},
408 {"break", "Exit for, while or until loop", builtin_not_written},
409 {"cd", "Change working directory", builtin_cd},
410 {"continue", "Continue for, while or until loop", builtin_not_written},
411 {"env", "Print all environment variables", builtin_env},
412 {"eval", "Construct and run shell command", builtin_eval},
413 {"exec", "Exec command, replacing this shell with the exec'd process",
414 builtin_exec},
415 {"exit", "Exit from shell()", builtin_exit},
416 {"export", "Set environment variable", builtin_export},
417 {"fg", "Bring job into the foreground", builtin_fg_bg},
418 {"jobs", "Lists the active jobs", builtin_jobs},
419 {"pwd", "Print current directory", builtin_pwd},
420 {"read", "Input environment variable", builtin_read},
421 {"return", "Return from a function", builtin_not_written},
422 {"set", "Set/unset shell local variables", builtin_set},
423 {"shift", "Shift positional parameters", builtin_shift},
424 {"trap", "Trap signals", builtin_not_written},
425 {"ulimit","Controls resource limits", builtin_not_written},
426 {"umask","Sets file creation mask", builtin_umask},
427 {"unset", "Unset environment variable", builtin_unset},
428 {".", "Source-in and run commands in a file", builtin_source},
429 {"help", "List shell built-in commands", builtin_help},
430 {NULL, NULL, NULL}
431};
432
433static const char *set_cwd(void)
434{
435 if(cwd==bb_msg_unknown)
436 cwd = NULL; /* xgetcwd(arg) called free(arg) */
437 cwd = xgetcwd((char *)cwd);
438 if (!cwd)
439 cwd = bb_msg_unknown;
440 return cwd;
441}
442
443/* built-in 'eval' handler */
444static int builtin_eval(struct child_prog *child)
445{
446 char *str = NULL;
447 int rcode = EXIT_SUCCESS;
448
449 if (child->argv[1]) {
450 str = make_string(child->argv + 1);
451 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
452 FLAG_PARSE_SEMICOLON);
453 free(str);
454 rcode = last_return_code;
455 }
456 return rcode;
457}
458
459/* built-in 'cd <path>' handler */
460static int builtin_cd(struct child_prog *child)
461{
462 char *newdir;
463 if (child->argv[1] == NULL)
464 newdir = getenv("HOME");
465 else
466 newdir = child->argv[1];
467 if (chdir(newdir)) {
468 printf("cd: %s: %s\n", newdir, strerror(errno));
469 return EXIT_FAILURE;
470 }
471 set_cwd();
472 return EXIT_SUCCESS;
473}
474
475/* built-in 'env' handler */
476static int builtin_env(struct child_prog *dummy ATTRIBUTE_UNUSED)
477{
478 char **e = environ;
479 if (e == NULL) return EXIT_FAILURE;
480 for (; *e; e++) {
481 puts(*e);
482 }
483 return EXIT_SUCCESS;
484}
485
486/* built-in 'exec' handler */
487static int builtin_exec(struct child_prog *child)
488{
489 if (child->argv[1] == NULL)
490 return EXIT_SUCCESS; /* Really? */
491 child->argv++;
492 pseudo_exec(child);
493 /* never returns */
494}
495
496/* built-in 'exit' handler */
497static int builtin_exit(struct child_prog *child)
498{
499 if (child->argv[1] == NULL)
500 exit(last_return_code);
501 exit (atoi(child->argv[1]));
502}
503
504/* built-in 'export VAR=value' handler */
505static int builtin_export(struct child_prog *child)
506{
507 int res = 0;
508 char *name = child->argv[1];
509
510 if (name == NULL) {
511 return (builtin_env(child));
512 }
513
514 name = strdup(name);
515
516 if(name) {
517 char *value = strchr(name, '=');
518
519 if (!value) {
520 char *tmp;
521 /* They are exporting something without an =VALUE */
522
523 value = get_local_var(name);
524 if (value) {
525 size_t ln = strlen(name);
526
527 tmp = realloc(name, ln+strlen(value)+2);
528 if(tmp==NULL)
529 res = -1;
530 else {
531 sprintf(tmp+ln, "=%s", value);
532 name = tmp;
533 }
534 } else {
535 /* bash does not return an error when trying to export
536 * an undefined variable. Do likewise. */
537 res = 1;
538 }
539 }
540 }
541 if (res<0)
542 bb_perror_msg("export");
543 else if(res==0)
544 res = set_local_var(name, 1);
545 else
546 res = 0;
547 free(name);
548 return res;
549}
550
551/* built-in 'fg' and 'bg' handler */
552static int builtin_fg_bg(struct child_prog *child)
553{
554 int i, jobnum;
555 struct pipe *pi=NULL;
556
557 if (!interactive)
558 return EXIT_FAILURE;
559 /* If they gave us no args, assume they want the last backgrounded task */
560 if (!child->argv[1]) {
561 for (pi = job_list; pi; pi = pi->next) {
562 if (pi->jobid == last_jobid) {
563 break;
564 }
565 }
566 if (!pi) {
567 bb_error_msg("%s: no current job", child->argv[0]);
568 return EXIT_FAILURE;
569 }
570 } else {
571 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
572 bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
573 return EXIT_FAILURE;
574 }
575 for (pi = job_list; pi; pi = pi->next) {
576 if (pi->jobid == jobnum) {
577 break;
578 }
579 }
580 if (!pi) {
581 bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
582 return EXIT_FAILURE;
583 }
584 }
585
586 if (*child->argv[0] == 'f') {
587 /* Put the job into the foreground. */
588 tcsetpgrp(shell_terminal, pi->pgrp);
589 }
590
591 /* Restart the processes in the job */
592 for (i = 0; i < pi->num_progs; i++)
593 pi->progs[i].is_stopped = 0;
594
595 if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
596 if (i == ESRCH) {
597 remove_bg_job(pi);
598 } else {
599 bb_perror_msg("kill (SIGCONT)");
600 }
601 }
602
603 pi->stopped_progs = 0;
604 return EXIT_SUCCESS;
605}
606
607/* built-in 'help' handler */
608static int builtin_help(struct child_prog *dummy ATTRIBUTE_UNUSED)
609{
610 const struct built_in_command *x;
611
612 printf("\nBuilt-in commands:\n");
613 printf("-------------------\n");
614 for (x = bltins; x->cmd; x++) {
615 if (x->descr==NULL)
616 continue;
617 printf("%s\t%s\n", x->cmd, x->descr);
618 }
619 printf("\n\n");
620 return EXIT_SUCCESS;
621}
622
623/* built-in 'jobs' handler */
624static int builtin_jobs(struct child_prog *child ATTRIBUTE_UNUSED)
625{
626 struct pipe *job;
627 char *status_string;
628
629 for (job = job_list; job; job = job->next) {
630 if (job->running_progs == job->stopped_progs)
631 status_string = "Stopped";
632 else
633 status_string = "Running";
634
635 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
636 }
637 return EXIT_SUCCESS;
638}
639
640
641/* built-in 'pwd' handler */
642static int builtin_pwd(struct child_prog *dummy ATTRIBUTE_UNUSED)
643{
644 puts(set_cwd());
645 return EXIT_SUCCESS;
646}
647
648/* built-in 'read VAR' handler */
649static int builtin_read(struct child_prog *child)
650{
651 int res;
652
653 if (child->argv[1]) {
654 char string[BUFSIZ];
655 char *var = 0;
656
657 string[0] = 0; /* In case stdin has only EOF */
658 /* read string */
659 fgets(string, sizeof(string), stdin);
660 chomp(string);
661 var = malloc(strlen(child->argv[1])+strlen(string)+2);
662 if(var) {
663 sprintf(var, "%s=%s", child->argv[1], string);
664 res = set_local_var(var, 0);
665 } else
666 res = -1;
667 if (res)
668 bb_perror_msg("read");
669 free(var); /* So not move up to avoid breaking errno */
670 return res;
671 } else {
672 do res=getchar(); while(res!='\n' && res!=EOF);
673 return 0;
674 }
675}
676
677/* built-in 'set VAR=value' handler */
678static int builtin_set(struct child_prog *child)
679{
680 char *temp = child->argv[1];
681 struct variables *e;
682
683 if (temp == NULL)
684 for(e = top_vars; e; e=e->next)
685 printf("%s=%s\n", e->name, e->value);
686 else
687 set_local_var(temp, 0);
688
689 return EXIT_SUCCESS;
690}
691
692
693/* Built-in 'shift' handler */
694static int builtin_shift(struct child_prog *child)
695{
696 int n=1;
697 if (child->argv[1]) {
698 n=atoi(child->argv[1]);
699 }
700 if (n>=0 && n<global_argc) {
701 /* XXX This probably breaks $0 */
702 global_argc -= n;
703 global_argv += n;
704 return EXIT_SUCCESS;
705 } else {
706 return EXIT_FAILURE;
707 }
708}
709
710/* Built-in '.' handler (read-in and execute commands from file) */
711static int builtin_source(struct child_prog *child)
712{
713 FILE *input;
714 int status;
715
716 if (child->argv[1] == NULL)
717 return EXIT_FAILURE;
718
719 /* XXX search through $PATH is missing */
720 input = fopen(child->argv[1], "r");
721 if (!input) {
722 bb_error_msg("Couldn't open file '%s'", child->argv[1]);
723 return EXIT_FAILURE;
724 }
725
726 /* Now run the file */
727 /* XXX argv and argc are broken; need to save old global_argv
728 * (pointer only is OK!) on this stack frame,
729 * set global_argv=child->argv+1, recurse, and restore. */
730 mark_open(fileno(input));
731 status = parse_file_outer(input);
732 mark_closed(fileno(input));
733 fclose(input);
734 return (status);
735}
736
737static int builtin_umask(struct child_prog *child)
738{
739 mode_t new_umask;
740 const char *arg = child->argv[1];
741 char *end;
742 if (arg) {
743 new_umask=strtoul(arg, &end, 8);
744 if (*end!='\0' || end == arg) {
745 return EXIT_FAILURE;
746 }
747 } else {
748 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
749 }
750 umask(new_umask);
751 return EXIT_SUCCESS;
752}
753
754/* built-in 'unset VAR' handler */
755static int builtin_unset(struct child_prog *child)
756{
757 /* bash returned already true */
758 unset_local_var(child->argv[1]);
759 return EXIT_SUCCESS;
760}
761
762static int builtin_not_written(struct child_prog *child)
763{
764 printf("builtin_%s not written\n",child->argv[0]);
765 return EXIT_FAILURE;
766}
767
768static int b_check_space(o_string *o, int len)
769{
770 /* It would be easy to drop a more restrictive policy
771 * in here, such as setting a maximum string length */
772 if (o->length + len > o->maxlen) {
773 char *old_data = o->data;
774 /* assert (data == NULL || o->maxlen != 0); */
775 o->maxlen += max(2*len, B_CHUNK);
776 o->data = realloc(o->data, 1 + o->maxlen);
777 if (o->data == NULL) {
778 free(old_data);
779 }
780 }
781 return o->data == NULL;
782}
783
784static int b_addchr(o_string *o, int ch)
785{
786 debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
787 if (b_check_space(o, 1)) return B_NOSPAC;
788 o->data[o->length] = ch;
789 o->length++;
790 o->data[o->length] = '\0';
791 return 0;
792}
793
794static void b_reset(o_string *o)
795{
796 o->length = 0;
797 o->nonnull = 0;
798 if (o->data != NULL) *o->data = '\0';
799}
800
801static void b_free(o_string *o)
802{
803 b_reset(o);
804 free(o->data);
805 o->data = NULL;
806 o->maxlen = 0;
807}
808
809/* My analysis of quoting semantics tells me that state information
810 * is associated with a destination, not a source.
811 */
812static int b_addqchr(o_string *o, int ch, int quote)
813{
814 if (quote && strchr("*?[\\",ch)) {
815 int rc;
816 rc = b_addchr(o, '\\');
817 if (rc) return rc;
818 }
819 return b_addchr(o, ch);
820}
821
822/* belongs in utility.c */
823static char *simple_itoa(unsigned int i)
824{
825 /* 21 digits plus null terminator, good for 64-bit or smaller ints */
826 static char local[22];
827 char *p = &local[21];
828 *p-- = '\0';
829 do {
830 *p-- = '0' + i % 10;
831 i /= 10;
832 } while (i > 0);
833 return p + 1;
834}
835
836static int b_adduint(o_string *o, unsigned int i)
837{
838 int r;
839 char *p = simple_itoa(i);
840 /* no escape checking necessary */
841 do r=b_addchr(o, *p++); while (r==0 && *p);
842 return r;
843}
844
845static int static_get(struct in_str *i)
846{
847 int ch=*i->p++;
848 if (ch=='\0') return EOF;
849 return ch;
850}
851
852static int static_peek(struct in_str *i)
853{
854 return *i->p;
855}
856
857static inline void cmdedit_set_initial_prompt(void)
858{
859#ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
860 PS1 = NULL;
861#else
862 PS1 = getenv("PS1");
863 if(PS1==0)
864 PS1 = "\\w \\$ ";
865#endif
866}
867
868static inline void setup_prompt_string(int promptmode, char **prompt_str)
869{
870 debug_printf("setup_prompt_string %d ",promptmode);
871#ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
872 /* Set up the prompt */
873 if (promptmode == 1) {
874 free(PS1);
875 PS1=xmalloc(strlen(cwd)+4);
876 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# ");
877 *prompt_str = PS1;
878 } else {
879 *prompt_str = PS2;
880 }
881#else
882 *prompt_str = (promptmode==1)? PS1 : PS2;
883#endif
884 debug_printf("result %s\n",*prompt_str);
885}
886
887static void get_user_input(struct in_str *i)
888{
889 char *prompt_str;
890 static char the_command[BUFSIZ];
891
892 setup_prompt_string(i->promptmode, &prompt_str);
893#ifdef CONFIG_FEATURE_COMMAND_EDITING
894 /*
895 ** enable command line editing only while a command line
896 ** is actually being read; otherwise, we'll end up bequeathing
897 ** atexit() handlers and other unwanted stuff to our
898 ** child processes (rob@sysgo.de)
899 */
900 cmdedit_read_input(prompt_str, the_command);
901#else
902 fputs(prompt_str, stdout);
903 fflush(stdout);
904 the_command[0]=fgetc(i->file);
905 the_command[1]='\0';
906#endif
907 fflush(stdout);
908 i->p = the_command;
909}
910
911/* This is the magic location that prints prompts
912 * and gets data back from the user */
913static int file_get(struct in_str *i)
914{
915 int ch;
916
917 ch = 0;
918 /* If there is data waiting, eat it up */
919 if (i->p && *i->p) {
920 ch=*i->p++;
921 } else {
922 /* need to double check i->file because we might be doing something
923 * more complicated by now, like sourcing or substituting. */
924 if (i->__promptme && interactive && i->file == stdin) {
925 while(! i->p || (interactive && strlen(i->p)==0) ) {
926 get_user_input(i);
927 }
928 i->promptmode=2;
929 i->__promptme = 0;
930 if (i->p && *i->p) {
931 ch=*i->p++;
932 }
933 } else {
934 ch = fgetc(i->file);
935 }
936
937 debug_printf("b_getch: got a %d\n", ch);
938 }
939 if (ch == '\n') i->__promptme=1;
940 return ch;
941}
942
943/* All the callers guarantee this routine will never be
944 * used right after a newline, so prompting is not needed.
945 */
946static int file_peek(struct in_str *i)
947{
948 if (i->p && *i->p) {
949 return *i->p;
950 } else {
951 i->peek_buf[0] = fgetc(i->file);
952 i->peek_buf[1] = '\0';
953 i->p = i->peek_buf;
954 debug_printf("b_peek: got a %d\n", *i->p);
955 return *i->p;
956 }
957}
958
959static void setup_file_in_str(struct in_str *i, FILE *f)
960{
961 i->peek = file_peek;
962 i->get = file_get;
963 i->__promptme=1;
964 i->promptmode=1;
965 i->file = f;
966 i->p = NULL;
967}
968
969static void setup_string_in_str(struct in_str *i, const char *s)
970{
971 i->peek = static_peek;
972 i->get = static_get;
973 i->__promptme=1;
974 i->promptmode=1;
975 i->p = s;
976}
977
978static void mark_open(int fd)
979{
980 struct close_me *new = xmalloc(sizeof(struct close_me));
981 new->fd = fd;
982 new->next = close_me_head;
983 close_me_head = new;
984}
985
986static void mark_closed(int fd)
987{
988 struct close_me *tmp;
989 if (close_me_head == NULL || close_me_head->fd != fd)
990 bb_error_msg_and_die("corrupt close_me");
991 tmp = close_me_head;
992 close_me_head = close_me_head->next;
993 free(tmp);
994}
995
996static void close_all(void)
997{
998 struct close_me *c;
999 for (c=close_me_head; c; c=c->next) {
1000 close(c->fd);
1001 }
1002 close_me_head = NULL;
1003}
1004
1005/* squirrel != NULL means we squirrel away copies of stdin, stdout,
1006 * and stderr if they are redirected. */
1007static int setup_redirects(struct child_prog *prog, int squirrel[])
1008{
1009 int openfd, mode;
1010 struct redir_struct *redir;
1011
1012 for (redir=prog->redirects; redir; redir=redir->next) {
1013 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1014 /* something went wrong in the parse. Pretend it didn't happen */
1015 continue;
1016 }
1017 if (redir->dup == -1) {
1018 mode=redir_table[redir->type].mode;
1019 openfd = open(redir->word.gl_pathv[0], mode, 0666);
1020 if (openfd < 0) {
1021 /* this could get lost if stderr has been redirected, but
1022 bash and ash both lose it as well (though zsh doesn't!) */
1023 bb_perror_msg("error opening %s", redir->word.gl_pathv[0]);
1024 return 1;
1025 }
1026 } else {
1027 openfd = redir->dup;
1028 }
1029
1030 if (openfd != redir->fd) {
1031 if (squirrel && redir->fd < 3) {
1032 squirrel[redir->fd] = dup(redir->fd);
1033 }
1034 if (openfd == -3) {
1035 close(openfd);
1036 } else {
1037 dup2(openfd, redir->fd);
1038 if (redir->dup == -1)
1039 close (openfd);
1040 }
1041 }
1042 }
1043 return 0;
1044}
1045
1046static void restore_redirects(int squirrel[])
1047{
1048 int i, fd;
1049 for (i=0; i<3; i++) {
1050 fd = squirrel[i];
1051 if (fd != -1) {
1052 /* No error checking. I sure wouldn't know what
1053 * to do with an error if I found one! */
1054 dup2(fd, i);
1055 close(fd);
1056 }
1057 }
1058}
1059
1060/* never returns */
1061/* XXX no exit() here. If you don't exec, use _exit instead.
1062 * The at_exit handlers apparently confuse the calling process,
1063 * in particular stdin handling. Not sure why? */
1064static void pseudo_exec(struct child_prog *child)
1065{
1066 int i, rcode;
1067 char *p;
1068 const struct built_in_command *x;
1069 if (child->argv) {
1070 for (i=0; is_assignment(child->argv[i]); i++) {
1071 debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1072 p = insert_var_value(child->argv[i]);
1073 putenv(strdup(p));
1074 if (p != child->argv[i]) free(p);
1075 }
1076 child->argv+=i; /* XXX this hack isn't so horrible, since we are about
1077 to exit, and therefore don't need to keep data
1078 structures consistent for free() use. */
1079 /* If a variable is assigned in a forest, and nobody listens,
1080 * was it ever really set?
1081 */
1082 if (child->argv[0] == NULL) {
1083 _exit(EXIT_SUCCESS);
1084 }
1085
1086 /*
1087 * Check if the command matches any of the builtins.
1088 * Depending on context, this might be redundant. But it's
1089 * easier to waste a few CPU cycles than it is to figure out
1090 * if this is one of those cases.
1091 */
1092 for (x = bltins; x->cmd; x++) {
1093 if (strcmp(child->argv[0], x->cmd) == 0 ) {
1094 debug_printf("builtin exec %s\n", child->argv[0]);
1095 rcode = x->function(child);
1096 fflush(stdout);
1097 _exit(rcode);
1098 }
1099 }
1100
1101 /* Check if the command matches any busybox internal commands
1102 * ("applets") here.
1103 * FIXME: This feature is not 100% safe, since
1104 * BusyBox is not fully reentrant, so we have no guarantee the things
1105 * from the .bss are still zeroed, or that things from .data are still
1106 * at their defaults. We could exec ourself from /proc/self/exe, but I
1107 * really dislike relying on /proc for things. We could exec ourself
1108 * from global_argv[0], but if we are in a chroot, we may not be able
1109 * to find ourself... */
1110#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1111 {
1112 int argc_l;
1113 char** argv_l=child->argv;
1114 char *name = child->argv[0];
1115
1116 /* Count argc for use in a second... */
1117 for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1118 optind = 1;
1119 debug_printf("running applet %s\n", name);
1120 run_applet_by_name(name, argc_l, child->argv);
1121 }
1122#endif
1123 debug_printf("exec of %s\n",child->argv[0]);
1124 execvp(child->argv[0],child->argv);
1125 bb_perror_msg("couldn't exec: %s",child->argv[0]);
1126 _exit(1);
1127 } else if (child->group) {
1128 debug_printf("runtime nesting to group\n");
1129 interactive=0; /* crucial!!!! */
1130 rcode = run_list_real(child->group);
1131 /* OK to leak memory by not calling free_pipe_list,
1132 * since this process is about to exit */
1133 _exit(rcode);
1134 } else {
1135 /* Can happen. See what bash does with ">foo" by itself. */
1136 debug_printf("trying to pseudo_exec null command\n");
1137 _exit(EXIT_SUCCESS);
1138 }
1139}
1140
1141static void insert_bg_job(struct pipe *pi)
1142{
1143 struct pipe *thejob;
1144
1145 /* Linear search for the ID of the job to use */
1146 pi->jobid = 1;
1147 for (thejob = job_list; thejob; thejob = thejob->next)
1148 if (thejob->jobid >= pi->jobid)
1149 pi->jobid = thejob->jobid + 1;
1150
1151 /* add thejob to the list of running jobs */
1152 if (!job_list) {
1153 thejob = job_list = xmalloc(sizeof(*thejob));
1154 } else {
1155 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1156 thejob->next = xmalloc(sizeof(*thejob));
1157 thejob = thejob->next;
1158 }
1159
1160 /* physically copy the struct job */
1161 memcpy(thejob, pi, sizeof(struct pipe));
1162 thejob->next = NULL;
1163 thejob->running_progs = thejob->num_progs;
1164 thejob->stopped_progs = 0;
1165 thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1166
1167 //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0])
1168 {
1169 char *bar=thejob->text;
1170 char **foo=pi->progs[0].argv;
1171 while(foo && *foo) {
1172 bar += sprintf(bar, "%s ", *foo++);
1173 }
1174 }
1175
1176 /* we don't wait for background thejobs to return -- append it
1177 to the list of backgrounded thejobs and leave it alone */
1178 printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1179 last_bg_pid = thejob->progs[0].pid;
1180 last_jobid = thejob->jobid;
1181}
1182
1183/* remove a backgrounded job */
1184static void remove_bg_job(struct pipe *pi)
1185{
1186 struct pipe *prev_pipe;
1187
1188 if (pi == job_list) {
1189 job_list = pi->next;
1190 } else {
1191 prev_pipe = job_list;
1192 while (prev_pipe->next != pi)
1193 prev_pipe = prev_pipe->next;
1194 prev_pipe->next = pi->next;
1195 }
1196 if (job_list)
1197 last_jobid = job_list->jobid;
1198 else
1199 last_jobid = 0;
1200
1201 pi->stopped_progs = 0;
1202 free_pipe(pi, 0);
1203 free(pi);
1204}
1205
1206/* Checks to see if any processes have exited -- if they
1207 have, figure out why and see if a job has completed */
1208static int checkjobs(struct pipe* fg_pipe)
1209{
1210 int attributes;
1211 int status;
1212 int prognum = 0;
1213 struct pipe *pi;
1214 pid_t childpid;
1215
1216 attributes = WUNTRACED;
1217 if (fg_pipe==NULL) {
1218 attributes |= WNOHANG;
1219 }
1220
1221 while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1222 if (fg_pipe) {
1223 int i, rcode = 0;
1224 for (i=0; i < fg_pipe->num_progs; i++) {
1225 if (fg_pipe->progs[i].pid == childpid) {
1226 if (i==fg_pipe->num_progs-1)
1227 rcode=WEXITSTATUS(status);
1228 (fg_pipe->num_progs)--;
1229 return(rcode);
1230 }
1231 }
1232 }
1233
1234 for (pi = job_list; pi; pi = pi->next) {
1235 prognum = 0;
1236 while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1237 prognum++;
1238 }
1239 if (prognum < pi->num_progs)
1240 break;
1241 }
1242
1243 if(pi==NULL) {
1244 debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1245 continue;
1246 }
1247
1248 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1249 /* child exited */
1250 pi->running_progs--;
1251 pi->progs[prognum].pid = 0;
1252
1253 if (!pi->running_progs) {
1254 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1255 remove_bg_job(pi);
1256 }
1257 } else {
1258 /* child stopped */
1259 pi->stopped_progs++;
1260 pi->progs[prognum].is_stopped = 1;
1261
1262#if 0
1263 /* Printing this stuff is a pain, since it tends to
1264 * overwrite the prompt an inconveinient moments. So
1265 * don't do that. */
1266 if (pi->stopped_progs == pi->num_progs) {
1267 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1268 }
1269#endif
1270 }
1271 }
1272
1273 if (childpid == -1 && errno != ECHILD)
1274 bb_perror_msg("waitpid");
1275
1276 /* move the shell to the foreground */
1277 //if (interactive && tcsetpgrp(shell_terminal, getpgid(0)))
1278 // bb_perror_msg("tcsetpgrp-2");
1279 return -1;
1280}
1281
1282/* Figure out our controlling tty, checking in order stderr,
1283 * stdin, and stdout. If check_pgrp is set, also check that
1284 * we belong to the foreground process group associated with
1285 * that tty. The value of shell_terminal is needed in order to call
1286 * tcsetpgrp(shell_terminal, ...); */
1287#if 0
1288static void controlling_tty(int check_pgrp)
1289{
1290 pid_t curpgrp;
1291
1292 if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1293 && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1294 && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1295 goto shell_terminal_error;
1296
1297 if (check_pgrp && curpgrp != getpgid(0))
1298 goto shell_terminal_error;
1299
1300 return;
1301
1302shell_terminal_error:
1303 shell_terminal = -1;
1304 return;
1305}
1306#endif
1307
1308/* run_pipe_real() starts all the jobs, but doesn't wait for anything
1309 * to finish. See checkjobs().
1310 *
1311 * return code is normally -1, when the caller has to wait for children
1312 * to finish to determine the exit status of the pipe. If the pipe
1313 * is a simple builtin command, however, the action is done by the
1314 * time run_pipe_real returns, and the exit code is provided as the
1315 * return value.
1316 *
1317 * The input of the pipe is always stdin, the output is always
1318 * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1319 * because it tries to avoid running the command substitution in
1320 * subshell, when that is in fact necessary. The subshell process
1321 * now has its stdout directed to the input of the appropriate pipe,
1322 * so this routine is noticeably simpler.
1323 */
1324static int run_pipe_real(struct pipe *pi)
1325{
1326 int i;
1327 int nextin, nextout;
1328 int pipefds[2]; /* pipefds[0] is for reading */
1329 struct child_prog *child;
1330 const struct built_in_command *x;
1331 char *p;
1332
1333 nextin = 0;
1334 pi->pgrp = -1;
1335
1336 /* Check if this is a simple builtin (not part of a pipe).
1337 * Builtins within pipes have to fork anyway, and are handled in
1338 * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
1339 */
1340 if (pi->num_progs == 1) child = & (pi->progs[0]);
1341 if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1342 int squirrel[] = {-1, -1, -1};
1343 int rcode;
1344 debug_printf("non-subshell grouping\n");
1345 setup_redirects(child, squirrel);
1346 /* XXX could we merge code with following builtin case,
1347 * by creating a pseudo builtin that calls run_list_real? */
1348 rcode = run_list_real(child->group);
1349 restore_redirects(squirrel);
1350 return rcode;
1351 } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1352 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1353 if (i!=0 && child->argv[i]==NULL) {
1354 /* assignments, but no command: set the local environment */
1355 for (i=0; child->argv[i]!=NULL; i++) {
1356
1357 /* Ok, this case is tricky. We have to decide if this is a
1358 * local variable, or an already exported variable. If it is
1359 * already exported, we have to export the new value. If it is
1360 * not exported, we need only set this as a local variable.
1361 * This junk is all to decide whether or not to export this
1362 * variable. */
1363 int export_me=0;
1364 char *name, *value;
1365 name = bb_xstrdup(child->argv[i]);
1366 debug_printf("Local environment set: %s\n", name);
1367 value = strchr(name, '=');
1368 if (value)
1369 *value=0;
1370 if ( get_local_var(name)) {
1371 export_me=1;
1372 }
1373 free(name);
1374 p = insert_var_value(child->argv[i]);
1375 set_local_var(p, export_me);
1376 if (p != child->argv[i]) free(p);
1377 }
1378 return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
1379 }
1380 for (i = 0; is_assignment(child->argv[i]); i++) {
1381 p = insert_var_value(child->argv[i]);
1382 putenv(strdup(p));
1383 if (p != child->argv[i]) {
1384 child->sp--;
1385 free(p);
1386 }
1387 }
1388 if (child->sp) {
1389 char * str = NULL;
1390
1391 str = make_string((child->argv + i));
1392 parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1393 free(str);
1394 return last_return_code;
1395 }
1396 for (x = bltins; x->cmd; x++) {
1397 if (strcmp(child->argv[i], x->cmd) == 0 ) {
1398 int squirrel[] = {-1, -1, -1};
1399 int rcode;
1400 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1401 debug_printf("magic exec\n");
1402 setup_redirects(child,NULL);
1403 return EXIT_SUCCESS;
1404 }
1405 debug_printf("builtin inline %s\n", child->argv[0]);
1406 /* XXX setup_redirects acts on file descriptors, not FILEs.
1407 * This is perfect for work that comes after exec().
1408 * Is it really safe for inline use? Experimentally,
1409 * things seem to work with glibc. */
1410 setup_redirects(child, squirrel);
1411 child->argv+=i; /* XXX horrible hack */
1412 rcode = x->function(child);
1413 child->argv-=i; /* XXX restore hack so free() can work right */
1414 restore_redirects(squirrel);
1415 return rcode;
1416 }
1417 }
1418 }
1419
1420 for (i = 0; i < pi->num_progs; i++) {
1421 child = & (pi->progs[i]);
1422
1423 /* pipes are inserted between pairs of commands */
1424 if ((i + 1) < pi->num_progs) {
1425 if (pipe(pipefds)<0) bb_perror_msg_and_die("pipe");
1426 nextout = pipefds[1];
1427 } else {
1428 nextout=1;
1429 pipefds[0] = -1;
1430 }
1431
1432 /* XXX test for failed fork()? */
1433#if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
1434 if (!(child->pid = fork()))
1435#else
1436 if (!(child->pid = vfork()))
1437#endif
1438 {
1439 /* Set the handling for job control signals back to the default. */
1440 signal(SIGINT, SIG_DFL);
1441 signal(SIGQUIT, SIG_DFL);
1442 signal(SIGTERM, SIG_DFL);
1443 signal(SIGTSTP, SIG_DFL);
1444 signal(SIGTTIN, SIG_DFL);
1445 signal(SIGTTOU, SIG_DFL);
1446 signal(SIGCHLD, SIG_DFL);
1447
1448 close_all();
1449
1450 if (nextin != 0) {
1451 dup2(nextin, 0);
1452 close(nextin);
1453 }
1454 if (nextout != 1) {
1455 dup2(nextout, 1);
1456 close(nextout);
1457 }
1458 if (pipefds[0]!=-1) {
1459 close(pipefds[0]); /* opposite end of our output pipe */
1460 }
1461
1462 /* Like bash, explicit redirects override pipes,
1463 * and the pipe fd is available for dup'ing. */
1464 setup_redirects(child,NULL);
1465
1466 if (interactive && pi->followup!=PIPE_BG) {
1467 /* If we (the child) win the race, put ourselves in the process
1468 * group whose leader is the first process in this pipe. */
1469 if (pi->pgrp < 0) {
1470 pi->pgrp = getpid();
1471 }
1472 if (setpgid(0, pi->pgrp) == 0) {
1473 tcsetpgrp(2, pi->pgrp);
1474 }
1475 }
1476
1477 pseudo_exec(child);
1478 }
1479
1480
1481 /* put our child in the process group whose leader is the
1482 first process in this pipe */
1483 if (pi->pgrp < 0) {
1484 pi->pgrp = child->pid;
1485 }
1486 /* Don't check for errors. The child may be dead already,
1487 * in which case setpgid returns error code EACCES. */
1488 setpgid(child->pid, pi->pgrp);
1489
1490 if (nextin != 0)
1491 close(nextin);
1492 if (nextout != 1)
1493 close(nextout);
1494
1495 /* If there isn't another process, nextin is garbage
1496 but it doesn't matter */
1497 nextin = pipefds[0];
1498 }
1499 return -1;
1500}
1501
1502static int run_list_real(struct pipe *pi)
1503{
1504 char *save_name = NULL;
1505 char **list = NULL;
1506 char **save_list = NULL;
1507 struct pipe *rpipe;
1508 int flag_rep = 0;
1509 int save_num_progs;
1510 int rcode=0, flag_skip=1;
1511 int flag_restore = 0;
1512 int if_code=0, next_if_code=0; /* need double-buffer to handle elif */
1513 reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1514 /* check syntax for "for" */
1515 for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1516 if ((rpipe->r_mode == RES_IN ||
1517 rpipe->r_mode == RES_FOR) &&
1518 (rpipe->next == NULL)) {
1519 syntax();
1520 return 1;
1521 }
1522 if ((rpipe->r_mode == RES_IN &&
1523 (rpipe->next->r_mode == RES_IN &&
1524 rpipe->next->progs->argv != NULL))||
1525 (rpipe->r_mode == RES_FOR &&
1526 rpipe->next->r_mode != RES_IN)) {
1527 syntax();
1528 return 1;
1529 }
1530 }
1531 for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1532 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1533 pi->r_mode == RES_FOR) {
1534 flag_restore = 0;
1535 if (!rpipe) {
1536 flag_rep = 0;
1537 rpipe = pi;
1538 }
1539 }
1540 rmode = pi->r_mode;
1541 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);
1542 if (rmode == skip_more_in_this_rmode && flag_skip) {
1543 if (pi->followup == PIPE_SEQ) flag_skip=0;
1544 continue;
1545 }
1546 flag_skip = 1;
1547 skip_more_in_this_rmode = RES_XXXX;
1548 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1549 if (rmode == RES_THEN && if_code) continue;
1550 if (rmode == RES_ELSE && !if_code) continue;
1551 if (rmode == RES_ELIF && !if_code) break;
1552 if (rmode == RES_FOR && pi->num_progs) {
1553 if (!list) {
1554 /* if no variable values after "in" we skip "for" */
1555 if (!pi->next->progs->argv) continue;
1556 /* create list of variable values */
1557 list = make_list_in(pi->next->progs->argv,
1558 pi->progs->argv[0]);
1559 save_list = list;
1560 save_name = pi->progs->argv[0];
1561 pi->progs->argv[0] = NULL;
1562 flag_rep = 1;
1563 }
1564 if (!(*list)) {
1565 free(pi->progs->argv[0]);
1566 free(save_list);
1567 list = NULL;
1568 flag_rep = 0;
1569 pi->progs->argv[0] = save_name;
1570 pi->progs->glob_result.gl_pathv[0] =
1571 pi->progs->argv[0];
1572 continue;
1573 } else {
1574 /* insert new value from list for variable */
1575 if (pi->progs->argv[0])
1576 free(pi->progs->argv[0]);
1577 pi->progs->argv[0] = *list++;
1578 pi->progs->glob_result.gl_pathv[0] =
1579 pi->progs->argv[0];
1580 }
1581 }
1582 if (rmode == RES_IN) continue;
1583 if (rmode == RES_DO) {
1584 if (!flag_rep) continue;
1585 }
1586 if ((rmode == RES_DONE)) {
1587 if (flag_rep) {
1588 flag_restore = 1;
1589 } else {
1590 rpipe = NULL;
1591 }
1592 }
1593 if (pi->num_progs == 0) continue;
1594 save_num_progs = pi->num_progs; /* save number of programs */
1595 rcode = run_pipe_real(pi);
1596 debug_printf("run_pipe_real returned %d\n",rcode);
1597 if (rcode!=-1) {
1598 /* We only ran a builtin: rcode was set by the return value
1599 * of run_pipe_real(), and we don't need to wait for anything. */
1600 } else if (pi->followup==PIPE_BG) {
1601 /* XXX check bash's behavior with nontrivial pipes */
1602 /* XXX compute jobid */
1603 /* XXX what does bash do with attempts to background builtins? */
1604 insert_bg_job(pi);
1605 rcode = EXIT_SUCCESS;
1606 } else {
1607 if (interactive) {
1608 /* move the new process group into the foreground */
1609 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1610 bb_perror_msg("tcsetpgrp-3");
1611 rcode = checkjobs(pi);
1612 /* move the shell to the foreground */
1613 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1614 bb_perror_msg("tcsetpgrp-4");
1615 } else {
1616 rcode = checkjobs(pi);
1617 }
1618 debug_printf("checkjobs returned %d\n",rcode);
1619 }
1620 last_return_code=rcode;
1621 pi->num_progs = save_num_progs; /* restore number of programs */
1622 if ( rmode == RES_IF || rmode == RES_ELIF )
1623 next_if_code=rcode; /* can be overwritten a number of times */
1624 if (rmode == RES_WHILE)
1625 flag_rep = !last_return_code;
1626 if (rmode == RES_UNTIL)
1627 flag_rep = last_return_code;
1628 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1629 (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1630 skip_more_in_this_rmode=rmode;
1631 checkjobs(NULL);
1632 }
1633 return rcode;
1634}
1635
1636/* broken, of course, but OK for testing */
1637static char *indenter(int i)
1638{
1639 static char blanks[]=" ";
1640 return &blanks[sizeof(blanks)-i-1];
1641}
1642
1643/* return code is the exit status of the pipe */
1644static int free_pipe(struct pipe *pi, int indent)
1645{
1646 char **p;
1647 struct child_prog *child;
1648 struct redir_struct *r, *rnext;
1649 int a, i, ret_code=0;
1650 char *ind = indenter(indent);
1651
1652 if (pi->stopped_progs > 0)
1653 return ret_code;
1654 final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1655 for (i=0; i<pi->num_progs; i++) {
1656 child = &pi->progs[i];
1657 final_printf("%s command %d:\n",ind,i);
1658 if (child->argv) {
1659 for (a=0,p=child->argv; *p; a++,p++) {
1660 final_printf("%s argv[%d] = %s\n",ind,a,*p);
1661 }
1662 globfree(&child->glob_result);
1663 child->argv=NULL;
1664 } else if (child->group) {
1665 final_printf("%s begin group (subshell:%d)\n",ind, child->subshell);
1666 ret_code = free_pipe_list(child->group,indent+3);
1667 final_printf("%s end group\n",ind);
1668 } else {
1669 final_printf("%s (nil)\n",ind);
1670 }
1671 for (r=child->redirects; r; r=rnext) {
1672 final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1673 if (r->dup == -1) {
1674 /* guard against the case >$FOO, where foo is unset or blank */
1675 if (r->word.gl_pathv) {
1676 final_printf(" %s\n", *r->word.gl_pathv);
1677 globfree(&r->word);
1678 }
1679 } else {
1680 final_printf("&%d\n", r->dup);
1681 }
1682 rnext=r->next;
1683 free(r);
1684 }
1685 child->redirects=NULL;
1686 }
1687 free(pi->progs); /* children are an array, they get freed all at once */
1688 pi->progs=NULL;
1689 return ret_code;
1690}
1691
1692static int free_pipe_list(struct pipe *head, int indent)
1693{
1694 int rcode=0; /* if list has no members */
1695 struct pipe *pi, *next;
1696 char *ind = indenter(indent);
1697 for (pi=head; pi; pi=next) {
1698 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
1699 rcode = free_pipe(pi, indent);
1700 final_printf("%s pipe followup code %d\n", ind, pi->followup);
1701 next=pi->next;
1702 pi->next=NULL;
1703 free(pi);
1704 }
1705 return rcode;
1706}
1707
1708/* Select which version we will use */
1709static int run_list(struct pipe *pi)
1710{
1711 int rcode=0;
1712 if (fake_mode==0) {
1713 rcode = run_list_real(pi);
1714 }
1715 /* free_pipe_list has the side effect of clearing memory
1716 * In the long run that function can be merged with run_list_real,
1717 * but doing that now would hobble the debugging effort. */
1718 free_pipe_list(pi,0);
1719 return rcode;
1720}
1721
1722/* The API for glob is arguably broken. This routine pushes a non-matching
1723 * string into the output structure, removing non-backslashed backslashes.
1724 * If someone can prove me wrong, by performing this function within the
1725 * original glob(3) api, feel free to rewrite this routine into oblivion.
1726 * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
1727 * XXX broken if the last character is '\\', check that before calling.
1728 */
1729static int globhack(const char *src, int flags, glob_t *pglob)
1730{
1731 int cnt=0, pathc;
1732 const char *s;
1733 char *dest;
1734 for (cnt=1, s=src; s && *s; s++) {
1735 if (*s == '\\') s++;
1736 cnt++;
1737 }
1738 dest = malloc(cnt);
1739 if (!dest) return GLOB_NOSPACE;
1740 if (!(flags & GLOB_APPEND)) {
1741 pglob->gl_pathv=NULL;
1742 pglob->gl_pathc=0;
1743 pglob->gl_offs=0;
1744 pglob->gl_offs=0;
1745 }
1746 pathc = ++pglob->gl_pathc;
1747 pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
1748 if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
1749 pglob->gl_pathv[pathc-1]=dest;
1750 pglob->gl_pathv[pathc]=NULL;
1751 for (s=src; s && *s; s++, dest++) {
1752 if (*s == '\\') s++;
1753 *dest = *s;
1754 }
1755 *dest='\0';
1756 return 0;
1757}
1758
1759/* XXX broken if the last character is '\\', check that before calling */
1760static int glob_needed(const char *s)
1761{
1762 for (; *s; s++) {
1763 if (*s == '\\') s++;
1764 if (strchr("*[?",*s)) return 1;
1765 }
1766 return 0;
1767}
1768
1769#if 0
1770static void globprint(glob_t *pglob)
1771{
1772 int i;
1773 debug_printf("glob_t at %p:\n", pglob);
1774 debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
1775 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
1776 for (i=0; i<pglob->gl_pathc; i++)
1777 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
1778 pglob->gl_pathv[i], pglob->gl_pathv[i]);
1779}
1780#endif
1781
1782static int xglob(o_string *dest, int flags, glob_t *pglob)
1783{
1784 int gr;
1785
1786 /* short-circuit for null word */
1787 /* we can code this better when the debug_printf's are gone */
1788 if (dest->length == 0) {
1789 if (dest->nonnull) {
1790 /* bash man page calls this an "explicit" null */
1791 gr = globhack(dest->data, flags, pglob);
1792 debug_printf("globhack returned %d\n",gr);
1793 } else {
1794 return 0;
1795 }
1796 } else if (glob_needed(dest->data)) {
1797 gr = glob(dest->data, flags, NULL, pglob);
1798 debug_printf("glob returned %d\n",gr);
1799 if (gr == GLOB_NOMATCH) {
1800 /* quote removal, or more accurately, backslash removal */
1801 gr = globhack(dest->data, flags, pglob);
1802 debug_printf("globhack returned %d\n",gr);
1803 }
1804 } else {
1805 gr = globhack(dest->data, flags, pglob);
1806 debug_printf("globhack returned %d\n",gr);
1807 }
1808 if (gr == GLOB_NOSPACE)
1809 bb_error_msg_and_die("out of memory during glob");
1810 if (gr != 0) { /* GLOB_ABORTED ? */
1811 bb_error_msg("glob(3) error %d",gr);
1812 }
1813 /* globprint(glob_target); */
1814 return gr;
1815}
1816
1817/* This is used to get/check local shell variables */
1818static char *get_local_var(const char *s)
1819{
1820 struct variables *cur;
1821
1822 if (!s)
1823 return NULL;
1824 for (cur = top_vars; cur; cur=cur->next)
1825 if(strcmp(cur->name, s)==0)
1826 return cur->value;
1827 return NULL;
1828}
1829
1830/* This is used to set local shell variables
1831 flg_export==0 if only local (not exporting) variable
1832 flg_export==1 if "new" exporting environ
1833 flg_export>1 if current startup environ (not call putenv()) */
1834static int set_local_var(const char *s, int flg_export)
1835{
1836 char *name, *value;
1837 int result=0;
1838 struct variables *cur;
1839
1840 name=strdup(s);
1841
1842 /* Assume when we enter this function that we are already in
1843 * NAME=VALUE format. So the first order of business is to
1844 * split 's' on the '=' into 'name' and 'value' */
1845 value = strchr(name, '=');
1846 if (value==0 && ++value==0) {
1847 free(name);
1848 return -1;
1849 }
1850 *value++ = 0;
1851
1852 for(cur = top_vars; cur; cur = cur->next) {
1853 if(strcmp(cur->name, name)==0)
1854 break;
1855 }
1856
1857 if(cur) {
1858 if(strcmp(cur->value, value)==0) {
1859 if(flg_export>0 && cur->flg_export==0)
1860 cur->flg_export=flg_export;
1861 else
1862 result++;
1863 } else {
1864 if(cur->flg_read_only) {
1865 bb_error_msg("%s: readonly variable", name);
1866 result = -1;
1867 } else {
1868 if(flg_export>0 || cur->flg_export>1)
1869 cur->flg_export=1;
1870 free(cur->value);
1871
1872 cur->value = strdup(value);
1873 }
1874 }
1875 } else {
1876 cur = malloc(sizeof(struct variables));
1877 if(!cur) {
1878 result = -1;
1879 } else {
1880 cur->name = strdup(name);
1881 if(cur->name == 0) {
1882 free(cur);
1883 result = -1;
1884 } else {
1885 struct variables *bottom = top_vars;
1886 cur->value = strdup(value);
1887 cur->next = 0;
1888 cur->flg_export = flg_export;
1889 cur->flg_read_only = 0;
1890 while(bottom->next) bottom=bottom->next;
1891 bottom->next = cur;
1892 }
1893 }
1894 }
1895
1896 if(result==0 && cur->flg_export==1) {
1897 *(value-1) = '=';
1898 result = putenv(name);
1899 } else {
1900 free(name);
1901 if(result>0) /* equivalent to previous set */
1902 result = 0;
1903 }
1904 return result;
1905}
1906
1907static void unset_local_var(const char *name)
1908{
1909 struct variables *cur;
1910
1911 if (name) {
1912 for (cur = top_vars; cur; cur=cur->next) {
1913 if(strcmp(cur->name, name)==0)
1914 break;
1915 }
1916 if(cur!=0) {
1917 struct variables *next = top_vars;
1918 if(cur->flg_read_only) {
1919 bb_error_msg("%s: readonly variable", name);
1920 return;
1921 } else {
1922 if(cur->flg_export)
1923 unsetenv(cur->name);
1924 free(cur->name);
1925 free(cur->value);
1926 while (next->next != cur)
1927 next = next->next;
1928 next->next = cur->next;
1929 }
1930 free(cur);
1931 }
1932 }
1933}
1934
1935static int is_assignment(const char *s)
1936{
1937 if (s==NULL || !isalpha(*s)) return 0;
1938 ++s;
1939 while(isalnum(*s) || *s=='_') ++s;
1940 return *s=='=';
1941}
1942
1943/* the src parameter allows us to peek forward to a possible &n syntax
1944 * for file descriptor duplication, e.g., "2>&1".
1945 * Return code is 0 normally, 1 if a syntax error is detected in src.
1946 * Resource errors (in xmalloc) cause the process to exit */
1947static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
1948 struct in_str *input)
1949{
1950 struct child_prog *child=ctx->child;
1951 struct redir_struct *redir = child->redirects;
1952 struct redir_struct *last_redir=NULL;
1953
1954 /* Create a new redir_struct and drop it onto the end of the linked list */
1955 while(redir) {
1956 last_redir=redir;
1957 redir=redir->next;
1958 }
1959 redir = xmalloc(sizeof(struct redir_struct));
1960 redir->next=NULL;
1961 redir->word.gl_pathv=NULL;
1962 if (last_redir) {
1963 last_redir->next=redir;
1964 } else {
1965 child->redirects=redir;
1966 }
1967
1968 redir->type=style;
1969 redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
1970
1971 debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
1972
1973 /* Check for a '2>&1' type redirect */
1974 redir->dup = redirect_dup_num(input);
1975 if (redir->dup == -2) return 1; /* syntax error */
1976 if (redir->dup != -1) {
1977 /* Erik had a check here that the file descriptor in question
1978 * is legit; I postpone that to "run time"
1979 * A "-" representation of "close me" shows up as a -3 here */
1980 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
1981 } else {
1982 /* We do _not_ try to open the file that src points to,
1983 * since we need to return and let src be expanded first.
1984 * Set ctx->pending_redirect, so we know what to do at the
1985 * end of the next parsed word.
1986 */
1987 ctx->pending_redirect = redir;
1988 }
1989 return 0;
1990}
1991
1992static struct pipe *new_pipe(void) {
1993 struct pipe *pi;
1994 pi = xmalloc(sizeof(struct pipe));
1995 pi->num_progs = 0;
1996 pi->progs = NULL;
1997 pi->next = NULL;
1998 pi->followup = 0; /* invalid */
1999 pi->r_mode = RES_NONE;
2000 return pi;
2001}
2002
2003static void initialize_context(struct p_context *ctx)
2004{
2005 ctx->pipe=NULL;
2006 ctx->pending_redirect=NULL;
2007 ctx->child=NULL;
2008 ctx->list_head=new_pipe();
2009 ctx->pipe=ctx->list_head;
2010 ctx->w=RES_NONE;
2011 ctx->stack=NULL;
2012 ctx->old_flag=0;
2013 done_command(ctx); /* creates the memory for working child */
2014}
2015
2016/* normal return is 0
2017 * if a reserved word is found, and processed, return 1
2018 * should handle if, then, elif, else, fi, for, while, until, do, done.
2019 * case, function, and select are obnoxious, save those for later.
2020 */
2021static int reserved_word(o_string *dest, struct p_context *ctx)
2022{
2023 struct reserved_combo {
2024 char *literal;
2025 int code;
2026 long flag;
2027 };
2028 /* Mostly a list of accepted follow-up reserved words.
2029 * FLAG_END means we are done with the sequence, and are ready
2030 * to turn the compound list into a command.
2031 * FLAG_START means the word must start a new compound list.
2032 */
2033 static struct reserved_combo reserved_list[] = {
2034 { "if", RES_IF, FLAG_THEN | FLAG_START },
2035 { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2036 { "elif", RES_ELIF, FLAG_THEN },
2037 { "else", RES_ELSE, FLAG_FI },
2038 { "fi", RES_FI, FLAG_END },
2039 { "for", RES_FOR, FLAG_IN | FLAG_START },
2040 { "while", RES_WHILE, FLAG_DO | FLAG_START },
2041 { "until", RES_UNTIL, FLAG_DO | FLAG_START },
2042 { "in", RES_IN, FLAG_DO },
2043 { "do", RES_DO, FLAG_DONE },
2044 { "done", RES_DONE, FLAG_END }
2045 };
2046 struct reserved_combo *r;
2047 for (r=reserved_list;
2048#define NRES sizeof(reserved_list)/sizeof(struct reserved_combo)
2049 r<reserved_list+NRES; r++) {
2050 if (strcmp(dest->data, r->literal) == 0) {
2051 debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2052 if (r->flag & FLAG_START) {
2053 struct p_context *new = xmalloc(sizeof(struct p_context));
2054 debug_printf("push stack\n");
2055 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2056 syntax();
2057 free(new);
2058 ctx->w = RES_SNTX;
2059 b_reset(dest);
2060 return 1;
2061 }
2062 *new = *ctx; /* physical copy */
2063 initialize_context(ctx);
2064 ctx->stack=new;
2065 } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2066 syntax();
2067 ctx->w = RES_SNTX;
2068 b_reset(dest);
2069 return 1;
2070 }
2071 ctx->w=r->code;
2072 ctx->old_flag = r->flag;
2073 if (ctx->old_flag & FLAG_END) {
2074 struct p_context *old;
2075 debug_printf("pop stack\n");
2076 done_pipe(ctx,PIPE_SEQ);
2077 old = ctx->stack;
2078 old->child->group = ctx->list_head;
2079 old->child->subshell = 0;
2080 *ctx = *old; /* physical copy */
2081 free(old);
2082 }
2083 b_reset (dest);
2084 return 1;
2085 }
2086 }
2087 return 0;
2088}
2089
2090/* normal return is 0.
2091 * Syntax or xglob errors return 1. */
2092static int done_word(o_string *dest, struct p_context *ctx)
2093{
2094 struct child_prog *child=ctx->child;
2095 glob_t *glob_target;
2096 int gr, flags = 0;
2097
2098 debug_printf("done_word: %s %p\n", dest->data, child);
2099 if (dest->length == 0 && !dest->nonnull) {
2100 debug_printf(" true null, ignored\n");
2101 return 0;
2102 }
2103 if (ctx->pending_redirect) {
2104 glob_target = &ctx->pending_redirect->word;
2105 } else {
2106 if (child->group) {
2107 syntax();
2108 return 1; /* syntax error, groups and arglists don't mix */
2109 }
2110 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2111 debug_printf("checking %s for reserved-ness\n",dest->data);
2112 if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2113 }
2114 glob_target = &child->glob_result;
2115 if (child->argv) flags |= GLOB_APPEND;
2116 }
2117 gr = xglob(dest, flags, glob_target);
2118 if (gr != 0) return 1;
2119
2120 b_reset(dest);
2121 if (ctx->pending_redirect) {
2122 ctx->pending_redirect=NULL;
2123 if (glob_target->gl_pathc != 1) {
2124 bb_error_msg("ambiguous redirect");
2125 return 1;
2126 }
2127 } else {
2128 child->argv = glob_target->gl_pathv;
2129 }
2130 if (ctx->w == RES_FOR) {
2131 done_word(dest,ctx);
2132 done_pipe(ctx,PIPE_SEQ);
2133 }
2134 return 0;
2135}
2136
2137/* The only possible error here is out of memory, in which case
2138 * xmalloc exits. */
2139static int done_command(struct p_context *ctx)
2140{
2141 /* The child is really already in the pipe structure, so
2142 * advance the pipe counter and make a new, null child.
2143 * Only real trickiness here is that the uncommitted
2144 * child structure, to which ctx->child points, is not
2145 * counted in pi->num_progs. */
2146 struct pipe *pi=ctx->pipe;
2147 struct child_prog *prog=ctx->child;
2148
2149 if (prog && prog->group == NULL
2150 && prog->argv == NULL
2151 && prog->redirects == NULL) {
2152 debug_printf("done_command: skipping null command\n");
2153 return 0;
2154 } else if (prog) {
2155 pi->num_progs++;
2156 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2157 } else {
2158 debug_printf("done_command: initializing\n");
2159 }
2160 pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2161
2162 prog = pi->progs + pi->num_progs;
2163 prog->redirects = NULL;
2164 prog->argv = NULL;
2165 prog->is_stopped = 0;
2166 prog->group = NULL;
2167 prog->glob_result.gl_pathv = NULL;
2168 prog->family = pi;
2169 prog->sp = 0;
2170 ctx->child = prog;
2171 prog->type = ctx->type;
2172
2173 /* but ctx->pipe and ctx->list_head remain unchanged */
2174 return 0;
2175}
2176
2177static int done_pipe(struct p_context *ctx, pipe_style type)
2178{
2179 struct pipe *new_p;
2180 done_command(ctx); /* implicit closure of previous command */
2181 debug_printf("done_pipe, type %d\n", type);
2182 ctx->pipe->followup = type;
2183 ctx->pipe->r_mode = ctx->w;
2184 new_p=new_pipe();
2185 ctx->pipe->next = new_p;
2186 ctx->pipe = new_p;
2187 ctx->child = NULL;
2188 done_command(ctx); /* set up new pipe to accept commands */
2189 return 0;
2190}
2191
2192/* peek ahead in the in_str to find out if we have a "&n" construct,
2193 * as in "2>&1", that represents duplicating a file descriptor.
2194 * returns either -2 (syntax error), -1 (no &), or the number found.
2195 */
2196static int redirect_dup_num(struct in_str *input)
2197{
2198 int ch, d=0, ok=0;
2199 ch = b_peek(input);
2200 if (ch != '&') return -1;
2201
2202 b_getch(input); /* get the & */
2203 ch=b_peek(input);
2204 if (ch == '-') {
2205 b_getch(input);
2206 return -3; /* "-" represents "close me" */
2207 }
2208 while (isdigit(ch)) {
2209 d = d*10+(ch-'0');
2210 ok=1;
2211 b_getch(input);
2212 ch = b_peek(input);
2213 }
2214 if (ok) return d;
2215
2216 bb_error_msg("ambiguous redirect");
2217 return -2;
2218}
2219
2220/* If a redirect is immediately preceded by a number, that number is
2221 * supposed to tell which file descriptor to redirect. This routine
2222 * looks for such preceding numbers. In an ideal world this routine
2223 * needs to handle all the following classes of redirects...
2224 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
2225 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
2226 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
2227 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
2228 * A -1 output from this program means no valid number was found, so the
2229 * caller should use the appropriate default for this redirection.
2230 */
2231static int redirect_opt_num(o_string *o)
2232{
2233 int num;
2234
2235 if (o->length==0) return -1;
2236 for(num=0; num<o->length; num++) {
2237 if (!isdigit(*(o->data+num))) {
2238 return -1;
2239 }
2240 }
2241 /* reuse num (and save an int) */
2242 num=atoi(o->data);
2243 b_reset(o);
2244 return num;
2245}
2246
2247static FILE *generate_stream_from_list(struct pipe *head)
2248{
2249 FILE *pf;
2250#if 1
2251 int pid, channel[2];
2252 if (pipe(channel)<0) bb_perror_msg_and_die("pipe");
2253#if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
2254 pid=fork();
2255#else
2256 pid=vfork();
2257#endif
2258 if (pid<0) {
2259 bb_perror_msg_and_die("fork");
2260 } else if (pid==0) {
2261 close(channel[0]);
2262 if (channel[1] != 1) {
2263 dup2(channel[1],1);
2264 close(channel[1]);
2265 }
2266#if 0
2267#define SURROGATE "surrogate response"
2268 write(1,SURROGATE,sizeof(SURROGATE));
2269 _exit(run_list(head));
2270#else
2271 _exit(run_list_real(head)); /* leaks memory */
2272#endif
2273 }
2274 debug_printf("forked child %d\n",pid);
2275 close(channel[1]);
2276 pf = fdopen(channel[0],"r");
2277 debug_printf("pipe on FILE *%p\n",pf);
2278#else
2279 free_pipe_list(head,0);
2280 pf=popen("echo surrogate response","r");
2281 debug_printf("started fake pipe on FILE *%p\n",pf);
2282#endif
2283 return pf;
2284}
2285
2286/* this version hacked for testing purposes */
2287/* return code is exit status of the process that is run. */
2288static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2289{
2290 int retcode;
2291 o_string result=NULL_O_STRING;
2292 struct p_context inner;
2293 FILE *p;
2294 struct in_str pipe_str;
2295 initialize_context(&inner);
2296
2297 /* recursion to generate command */
2298 retcode = parse_stream(&result, &inner, input, subst_end);
2299 if (retcode != 0) return retcode; /* syntax error or EOF */
2300 done_word(&result, &inner);
2301 done_pipe(&inner, PIPE_SEQ);
2302 b_free(&result);
2303
2304 p=generate_stream_from_list(inner.list_head);
2305 if (p==NULL) return 1;
2306 mark_open(fileno(p));
2307 setup_file_in_str(&pipe_str, p);
2308
2309 /* now send results of command back into original context */
2310 retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2311 /* XXX In case of a syntax error, should we try to kill the child?
2312 * That would be tough to do right, so just read until EOF. */
2313 if (retcode == 1) {
2314 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2315 }
2316
2317 debug_printf("done reading from pipe, pclose()ing\n");
2318 /* This is the step that wait()s for the child. Should be pretty
2319 * safe, since we just read an EOF from its stdout. We could try
2320 * to better, by using wait(), and keeping track of background jobs
2321 * at the same time. That would be a lot of work, and contrary
2322 * to the KISS philosophy of this program. */
2323 mark_closed(fileno(p));
2324 retcode=pclose(p);
2325 free_pipe_list(inner.list_head,0);
2326 debug_printf("pclosed, retcode=%d\n",retcode);
2327 /* XXX this process fails to trim a single trailing newline */
2328 return retcode;
2329}
2330
2331static int parse_group(o_string *dest, struct p_context *ctx,
2332 struct in_str *input, int ch)
2333{
2334 int rcode, endch=0;
2335 struct p_context sub;
2336 struct child_prog *child = ctx->child;
2337 if (child->argv) {
2338 syntax();
2339 return 1; /* syntax error, groups and arglists don't mix */
2340 }
2341 initialize_context(&sub);
2342 switch(ch) {
2343 case '(': endch=')'; child->subshell=1; break;
2344 case '{': endch='}'; break;
2345 default: syntax(); /* really logic error */
2346 }
2347 rcode=parse_stream(dest,&sub,input,endch);
2348 done_word(dest,&sub); /* finish off the final word in the subcontext */
2349 done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
2350 child->group = sub.list_head;
2351 return rcode;
2352 /* child remains "open", available for possible redirects */
2353}
2354
2355/* basically useful version until someone wants to get fancier,
2356 * see the bash man page under "Parameter Expansion" */
2357static char *lookup_param(char *src)
2358{
2359 char *p=NULL;
2360 if (src) {
2361 p = getenv(src);
2362 if (!p)
2363 p = get_local_var(src);
2364 }
2365 return p;
2366}
2367
2368/* return code: 0 for OK, 1 for syntax error */
2369static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2370{
2371 int i, advance=0;
2372 char sep[]=" ";
2373 int ch = input->peek(input); /* first character after the $ */
2374 debug_printf("handle_dollar: ch=%c\n",ch);
2375 if (isalpha(ch)) {
2376 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2377 ctx->child->sp++;
2378 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2379 b_getch(input);
2380 b_addchr(dest,ch);
2381 }
2382 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2383 } else if (isdigit(ch)) {
2384 i = ch-'0'; /* XXX is $0 special? */
2385 if (i<global_argc) {
2386 parse_string(dest, ctx, global_argv[i]); /* recursion */
2387 }
2388 advance = 1;
2389 } else switch (ch) {
2390 case '$':
2391 b_adduint(dest,getpid());
2392 advance = 1;
2393 break;
2394 case '!':
2395 if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2396 advance = 1;
2397 break;
2398 case '?':
2399 b_adduint(dest,last_return_code);
2400 advance = 1;
2401 break;
2402 case '#':
2403 b_adduint(dest,global_argc ? global_argc-1 : 0);
2404 advance = 1;
2405 break;
2406 case '{':
2407 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2408 ctx->child->sp++;
2409 b_getch(input);
2410 /* XXX maybe someone will try to escape the '}' */
2411 while(ch=b_getch(input),ch!=EOF && ch!='}') {
2412 b_addchr(dest,ch);
2413 }
2414 if (ch != '}') {
2415 syntax();
2416 return 1;
2417 }
2418 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2419 break;
2420 case '(':
2421 b_getch(input);
2422 process_command_subs(dest, ctx, input, ')');
2423 break;
2424 case '*':
2425 sep[0]=ifs[0];
2426 for (i=1; i<global_argc; i++) {
2427 parse_string(dest, ctx, global_argv[i]);
2428 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2429 }
2430 break;
2431 case '@':
2432 case '-':
2433 case '_':
2434 /* still unhandled, but should be eventually */
2435 bb_error_msg("unhandled syntax: $%c",ch);
2436 return 1;
2437 break;
2438 default:
2439 b_addqchr(dest,'$',dest->quote);
2440 }
2441 /* Eat the character if the flag was set. If the compiler
2442 * is smart enough, we could substitute "b_getch(input);"
2443 * for all the "advance = 1;" above, and also end up with
2444 * a nice size-optimized program. Hah! That'll be the day.
2445 */
2446 if (advance) b_getch(input);
2447 return 0;
2448}
2449
2450int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2451{
2452 struct in_str foo;
2453 setup_string_in_str(&foo, src);
2454 return parse_stream(dest, ctx, &foo, '\0');
2455}
2456
2457/* return code is 0 for normal exit, 1 for syntax error */
2458int parse_stream(o_string *dest, struct p_context *ctx,
2459 struct in_str *input, int end_trigger)
2460{
2461 int ch, m;
2462 int redir_fd;
2463 redir_type redir_style;
2464 int next;
2465
2466 /* Only double-quote state is handled in the state variable dest->quote.
2467 * A single-quote triggers a bypass of the main loop until its mate is
2468 * found. When recursing, quote state is passed in via dest->quote. */
2469
2470 debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2471 while ((ch=b_getch(input))!=EOF) {
2472 m = map[ch];
2473 next = (ch == '\n') ? 0 : b_peek(input);
2474 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
2475 ch,ch,m,dest->quote);
2476 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2477 b_addqchr(dest, ch, dest->quote);
2478 } else {
2479 if (m==2) { /* unquoted IFS */
2480 if (done_word(dest, ctx)) {
2481 return 1;
2482 }
2483 /* If we aren't performing a substitution, treat a newline as a
2484 * command separator. */
2485 if (end_trigger != '\0' && ch=='\n')
2486 done_pipe(ctx,PIPE_SEQ);
2487 }
2488 if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2489 debug_printf("leaving parse_stream (triggered)\n");
2490 return 0;
2491 }
2492#if 0
2493 if (ch=='\n') {
2494 /* Yahoo! Time to run with it! */
2495 done_pipe(ctx,PIPE_SEQ);
2496 run_list(ctx->list_head);
2497 initialize_context(ctx);
2498 }
2499#endif
2500 if (m!=2) switch (ch) {
2501 case '#':
2502 if (dest->length == 0 && !dest->quote) {
2503 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2504 } else {
2505 b_addqchr(dest, ch, dest->quote);
2506 }
2507 break;
2508 case '\\':
2509 if (next == EOF) {
2510 syntax();
2511 return 1;
2512 }
2513 b_addqchr(dest, '\\', dest->quote);
2514 b_addqchr(dest, b_getch(input), dest->quote);
2515 break;
2516 case '$':
2517 if (handle_dollar(dest, ctx, input)!=0) return 1;
2518 break;
2519 case '\'':
2520 dest->nonnull = 1;
2521 while(ch=b_getch(input),ch!=EOF && ch!='\'') {
2522 b_addchr(dest,ch);
2523 }
2524 if (ch==EOF) {
2525 syntax();
2526 return 1;
2527 }
2528 break;
2529 case '"':
2530 dest->nonnull = 1;
2531 dest->quote = !dest->quote;
2532 break;
2533 case '`':
2534 process_command_subs(dest, ctx, input, '`');
2535 break;
2536 case '>':
2537 redir_fd = redirect_opt_num(dest);
2538 done_word(dest, ctx);
2539 redir_style=REDIRECT_OVERWRITE;
2540 if (next == '>') {
2541 redir_style=REDIRECT_APPEND;
2542 b_getch(input);
2543 } else if (next == '(') {
2544 syntax(); /* until we support >(list) Process Substitution */
2545 return 1;
2546 }
2547 setup_redirect(ctx, redir_fd, redir_style, input);
2548 break;
2549 case '<':
2550 redir_fd = redirect_opt_num(dest);
2551 done_word(dest, ctx);
2552 redir_style=REDIRECT_INPUT;
2553 if (next == '<') {
2554 redir_style=REDIRECT_HEREIS;
2555 b_getch(input);
2556 } else if (next == '>') {
2557 redir_style=REDIRECT_IO;
2558 b_getch(input);
2559 } else if (next == '(') {
2560 syntax(); /* until we support <(list) Process Substitution */
2561 return 1;
2562 }
2563 setup_redirect(ctx, redir_fd, redir_style, input);
2564 break;
2565 case ';':
2566 done_word(dest, ctx);
2567 done_pipe(ctx,PIPE_SEQ);
2568 break;
2569 case '&':
2570 done_word(dest, ctx);
2571 if (next=='&') {
2572 b_getch(input);
2573 done_pipe(ctx,PIPE_AND);
2574 } else {
2575 done_pipe(ctx,PIPE_BG);
2576 }
2577 break;
2578 case '|':
2579 done_word(dest, ctx);
2580 if (next=='|') {
2581 b_getch(input);
2582 done_pipe(ctx,PIPE_OR);
2583 } else {
2584 /* we could pick up a file descriptor choice here
2585 * with redirect_opt_num(), but bash doesn't do it.
2586 * "echo foo 2| cat" yields "foo 2". */
2587 done_command(ctx);
2588 }
2589 break;
2590 case '(':
2591 case '{':
2592 if (parse_group(dest, ctx, input, ch)!=0) return 1;
2593 break;
2594 case ')':
2595 case '}':
2596 syntax(); /* Proper use of this character caught by end_trigger */
2597 return 1;
2598 break;
2599 default:
2600 syntax(); /* this is really an internal logic error */
2601 return 1;
2602 }
2603 }
2604 }
2605 /* complain if quote? No, maybe we just finished a command substitution
2606 * that was quoted. Example:
2607 * $ echo "`cat foo` plus more"
2608 * and we just got the EOF generated by the subshell that ran "cat foo"
2609 * The only real complaint is if we got an EOF when end_trigger != '\0',
2610 * that is, we were really supposed to get end_trigger, and never got
2611 * one before the EOF. Can't use the standard "syntax error" return code,
2612 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
2613 debug_printf("leaving parse_stream (EOF)\n");
2614 if (end_trigger != '\0') return -1;
2615 return 0;
2616}
2617
2618static void mapset(const char *set, int code)
2619{
2620 const unsigned char *s;
2621 for (s = (const unsigned char *)set; *s; s++) map[(int)*s] = code;
2622}
2623
2624static void update_ifs_map(void)
2625{
2626 /* char *ifs and char map[256] are both globals. */
2627 ifs = getenv("IFS");
2628 if (ifs == NULL) ifs=" \t\n";
2629 /* Precompute a list of 'flow through' behavior so it can be treated
2630 * quickly up front. Computation is necessary because of IFS.
2631 * Special case handling of IFS == " \t\n" is not implemented.
2632 * The map[] array only really needs two bits each, and on most machines
2633 * that would be faster because of the reduced L1 cache footprint.
2634 */
2635 memset(map,0,sizeof(map)); /* most characters flow through always */
2636 mapset("\\$'\"`", 3); /* never flow through */
2637 mapset("<>;&|(){}#", 1); /* flow through if quoted */
2638 mapset(ifs, 2); /* also flow through if quoted */
2639}
2640
2641/* most recursion does not come through here, the exception is
2642 * from builtin_source() */
2643int parse_stream_outer(struct in_str *inp, int flag)
2644{
2645
2646 struct p_context ctx;
2647 o_string temp=NULL_O_STRING;
2648 int rcode;
2649 do {
2650 ctx.type = flag;
2651 initialize_context(&ctx);
2652 update_ifs_map();
2653 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
2654 inp->promptmode=1;
2655 rcode = parse_stream(&temp, &ctx, inp, '\n');
2656 if (rcode != 1 && ctx.old_flag != 0) {
2657 syntax();
2658 }
2659 if (rcode != 1 && ctx.old_flag == 0) {
2660 done_word(&temp, &ctx);
2661 done_pipe(&ctx,PIPE_SEQ);
2662 run_list(ctx.list_head);
2663 } else {
2664 if (ctx.old_flag != 0) {
2665 free(ctx.stack);
2666 b_reset(&temp);
2667 }
2668 temp.nonnull = 0;
2669 temp.quote = 0;
2670 inp->p = NULL;
2671 free_pipe_list(ctx.list_head,0);
2672 }
2673 b_free(&temp);
2674 } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
2675 return 0;
2676}
2677
2678static int parse_string_outer(const char *s, int flag)
2679{
2680 struct in_str input;
2681 setup_string_in_str(&input, s);
2682 return parse_stream_outer(&input, flag);
2683}
2684
2685static int parse_file_outer(FILE *f)
2686{
2687 int rcode;
2688 struct in_str input;
2689 setup_file_in_str(&input, f);
2690 rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
2691 return rcode;
2692}
2693
2694/* Make sure we have a controlling tty. If we get started under a job
2695 * aware app (like bash for example), make sure we are now in charge so
2696 * we don't fight over who gets the foreground */
2697static void setup_job_control(void)
2698{
2699 static pid_t shell_pgrp;
2700 /* Loop until we are in the foreground. */
2701 while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
2702 kill (- shell_pgrp, SIGTTIN);
2703
2704 /* Ignore interactive and job-control signals. */
2705 signal(SIGINT, SIG_IGN);
2706 signal(SIGQUIT, SIG_IGN);
2707 signal(SIGTERM, SIG_IGN);
2708 signal(SIGTSTP, SIG_IGN);
2709 signal(SIGTTIN, SIG_IGN);
2710 signal(SIGTTOU, SIG_IGN);
2711 signal(SIGCHLD, SIG_IGN);
2712
2713 /* Put ourselves in our own process group. */
2714 setsid();
2715 shell_pgrp = getpid ();
2716 setpgid (shell_pgrp, shell_pgrp);
2717
2718 /* Grab control of the terminal. */
2719 tcsetpgrp(shell_terminal, shell_pgrp);
2720}
2721
2722int hush_main(int argc, char **argv)
2723{
2724 int opt;
2725 FILE *input;
2726 char **e = environ;
2727
2728 /* XXX what should these be while sourcing /etc/profile? */
2729 global_argc = argc;
2730 global_argv = argv;
2731
2732 /* (re?) initialize globals. Sometimes hush_main() ends up calling
2733 * hush_main(), therefore we cannot rely on the BSS to zero out this
2734 * stuff. Reset these to 0 every time. */
2735 ifs = NULL;
2736 /* map[] is taken care of with call to update_ifs_map() */
2737 fake_mode = 0;
2738 interactive = 0;
2739 close_me_head = NULL;
2740 last_bg_pid = 0;
2741 job_list = NULL;
2742 last_jobid = 0;
2743
2744 /* Initialize some more globals to non-zero values */
2745 set_cwd();
2746#ifdef CONFIG_FEATURE_COMMAND_EDITING
2747 cmdedit_set_initial_prompt();
2748#else
2749 PS1 = NULL;
2750#endif
2751 PS2 = "> ";
2752
2753 /* initialize our shell local variables with the values
2754 * currently living in the environment */
2755 if (e) {
2756 for (; *e; e++)
2757 set_local_var(*e, 2); /* without call putenv() */
2758 }
2759
2760 last_return_code=EXIT_SUCCESS;
2761
2762
2763 if (argv[0] && argv[0][0] == '-') {
2764 debug_printf("\nsourcing /etc/profile\n");
2765 if ((input = fopen("/etc/profile", "r")) != NULL) {
2766 mark_open(fileno(input));
2767 parse_file_outer(input);
2768 mark_closed(fileno(input));
2769 fclose(input);
2770 }
2771 }
2772 input=stdin;
2773
2774 while ((opt = getopt(argc, argv, "c:xif")) > 0) {
2775 switch (opt) {
2776 case 'c':
2777 {
2778 global_argv = argv+optind;
2779 global_argc = argc-optind;
2780 opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
2781 goto final_return;
2782 }
2783 break;
2784 case 'i':
2785 interactive++;
2786 break;
2787 case 'f':
2788 fake_mode++;
2789 break;
2790 default:
2791#ifndef BB_VER
2792 fprintf(stderr, "Usage: sh [FILE]...\n"
2793 " or: sh -c command [args]...\n\n");
2794 exit(EXIT_FAILURE);
2795#else
2796 bb_show_usage();
2797#endif
2798 }
2799 }
2800 /* A shell is interactive if the `-i' flag was given, or if all of
2801 * the following conditions are met:
2802 * no -c command
2803 * no arguments remaining or the -s flag given
2804 * standard input is a terminal
2805 * standard output is a terminal
2806 * Refer to Posix.2, the description of the `sh' utility. */
2807 if (argv[optind]==NULL && input==stdin &&
2808 isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
2809 interactive++;
2810 }
2811
2812 debug_printf("\ninteractive=%d\n", interactive);
2813 if (interactive) {
2814 /* Looks like they want an interactive shell */
2815#ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
2816 printf( "\n\n%s hush - the humble shell v0.01 (testing)\n",
2817 BB_BANNER);
2818 printf( "Enter 'help' for a list of built-in commands.\n\n");
2819#endif
2820 setup_job_control();
2821 }
2822
2823 if (argv[optind]==NULL) {
2824 opt=parse_file_outer(stdin);
2825 goto final_return;
2826 }
2827
2828 debug_printf("\nrunning script '%s'\n", argv[optind]);
2829 global_argv = argv+optind;
2830 global_argc = argc-optind;
2831 input = bb_xfopen(argv[optind], "r");
2832 opt = parse_file_outer(input);
2833
2834#ifdef CONFIG_FEATURE_CLEAN_UP
2835 fclose(input);
2836 if (cwd && cwd != bb_msg_unknown)
2837 free((char*)cwd);
2838 {
2839 struct variables *cur, *tmp;
2840 for(cur = top_vars; cur; cur = tmp) {
2841 tmp = cur->next;
2842 if (!cur->flg_read_only) {
2843 free(cur->name);
2844 free(cur->value);
2845 free(cur);
2846 }
2847 }
2848 }
2849#endif
2850
2851final_return:
2852 return(opt?opt:last_return_code);
2853}
2854
2855static char *insert_var_value(char *inp)
2856{
2857 int res_str_len = 0;
2858 int len;
2859 int done = 0;
2860 char *p, *p1, *res_str = NULL;
2861
2862 while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
2863 if (p != inp) {
2864 len = p - inp;
2865 res_str = xrealloc(res_str, (res_str_len + len));
2866 strncpy((res_str + res_str_len), inp, len);
2867 res_str_len += len;
2868 }
2869 inp = ++p;
2870 p = strchr(inp, SPECIAL_VAR_SYMBOL);
2871 *p = '\0';
2872 if ((p1 = lookup_param(inp))) {
2873 len = res_str_len + strlen(p1);
2874 res_str = xrealloc(res_str, (1 + len));
2875 strcpy((res_str + res_str_len), p1);
2876 res_str_len = len;
2877 }
2878 *p = SPECIAL_VAR_SYMBOL;
2879 inp = ++p;
2880 done = 1;
2881 }
2882 if (done) {
2883 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
2884 strcpy((res_str + res_str_len), inp);
2885 while ((p = strchr(res_str, '\n'))) {
2886 *p = ' ';
2887 }
2888 }
2889 return (res_str == NULL) ? inp : res_str;
2890}
2891
2892static char **make_list_in(char **inp, char *name)
2893{
2894 int len, i;
2895 int name_len = strlen(name);
2896 int n = 0;
2897 char **list;
2898 char *p1, *p2, *p3;
2899
2900 /* create list of variable values */
2901 list = xmalloc(sizeof(*list));
2902 for (i = 0; inp[i]; i++) {
2903 p3 = insert_var_value(inp[i]);
2904 p1 = p3;
2905 while (*p1) {
2906 if ((*p1 == ' ')) {
2907 p1++;
2908 continue;
2909 }
2910 if ((p2 = strchr(p1, ' '))) {
2911 len = p2 - p1;
2912 } else {
2913 len = strlen(p1);
2914 p2 = p1 + len;
2915 }
2916 /* we use n + 2 in realloc for list,because we add
2917 * new element and then we will add NULL element */
2918 list = xrealloc(list, sizeof(*list) * (n + 2));
2919 list[n] = xmalloc(2 + name_len + len);
2920 strcpy(list[n], name);
2921 strcat(list[n], "=");
2922 strncat(list[n], p1, len);
2923 list[n++][name_len + len + 1] = '\0';
2924 p1 = p2;
2925 }
2926 if (p3 != inp[i]) free(p3);
2927 }
2928 list[n] = NULL;
2929 return list;
2930}
2931
2932/* Make new string for parser */
2933static char * make_string(char ** inp)
2934{
2935 char *p;
2936 char *str = NULL;
2937 int n;
2938 int len = 2;
2939
2940 for (n = 0; inp[n]; n++) {
2941 p = insert_var_value(inp[n]);
2942 str = xrealloc(str, (len + strlen(p)));
2943 if (n) {
2944 strcat(str, " ");
2945 } else {
2946 *str = '\0';
2947 }
2948 strcat(str, p);
2949 len = strlen(str) + 3;
2950 if (p != inp[n]) free(p);
2951 }
2952 len = strlen(str);
2953 *(str + len) = '\n';
2954 *(str + len + 1) = '\0';
2955 return str;
2956}
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