Contents of /trunk/mkinitrd-magellan/busybox/shell/hush.c
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Sat Sep 1 22:45:15 2007 UTC (17 years ago) by niro
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Sat Sep 1 22:45:15 2007 UTC (17 years ago) by niro
File MIME type: text/plain
File size: 79488 byte(s)
-import if magellan mkinitrd; it is a fork of redhats mkinitrd-5.0.8 with all magellan patches and features; deprecates magellan-src/mkinitrd
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 | #include "cmdedit.h" |
102 | |
103 | #define SPECIAL_VAR_SYMBOL 03 |
104 | #define FLAG_EXIT_FROM_LOOP 1 |
105 | #define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */ |
106 | #define FLAG_REPARSING (1 << 2) /* >=2nd pass */ |
107 | |
108 | typedef enum { |
109 | REDIRECT_INPUT = 1, |
110 | REDIRECT_OVERWRITE = 2, |
111 | REDIRECT_APPEND = 3, |
112 | REDIRECT_HEREIS = 4, |
113 | REDIRECT_IO = 5 |
114 | } redir_type; |
115 | |
116 | /* The descrip member of this structure is only used to make debugging |
117 | * output pretty */ |
118 | static const struct {int mode; int default_fd; const char *descrip;} redir_table[] = { |
119 | { 0, 0, "()" }, |
120 | { O_RDONLY, 0, "<" }, |
121 | { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" }, |
122 | { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" }, |
123 | { O_RDONLY, -1, "<<" }, |
124 | { O_RDWR, 1, "<>" } |
125 | }; |
126 | |
127 | typedef enum { |
128 | PIPE_SEQ = 1, |
129 | PIPE_AND = 2, |
130 | PIPE_OR = 3, |
131 | PIPE_BG = 4, |
132 | } pipe_style; |
133 | |
134 | /* might eventually control execution */ |
135 | typedef enum { |
136 | RES_NONE = 0, |
137 | RES_IF = 1, |
138 | RES_THEN = 2, |
139 | RES_ELIF = 3, |
140 | RES_ELSE = 4, |
141 | RES_FI = 5, |
142 | RES_FOR = 6, |
143 | RES_WHILE = 7, |
144 | RES_UNTIL = 8, |
145 | RES_DO = 9, |
146 | RES_DONE = 10, |
147 | RES_XXXX = 11, |
148 | RES_IN = 12, |
149 | RES_SNTX = 13 |
150 | } reserved_style; |
151 | #define FLAG_END (1<<RES_NONE) |
152 | #define FLAG_IF (1<<RES_IF) |
153 | #define FLAG_THEN (1<<RES_THEN) |
154 | #define FLAG_ELIF (1<<RES_ELIF) |
155 | #define FLAG_ELSE (1<<RES_ELSE) |
156 | #define FLAG_FI (1<<RES_FI) |
157 | #define FLAG_FOR (1<<RES_FOR) |
158 | #define FLAG_WHILE (1<<RES_WHILE) |
159 | #define FLAG_UNTIL (1<<RES_UNTIL) |
160 | #define FLAG_DO (1<<RES_DO) |
161 | #define FLAG_DONE (1<<RES_DONE) |
162 | #define FLAG_IN (1<<RES_IN) |
163 | #define FLAG_START (1<<RES_XXXX) |
164 | |
165 | /* This holds pointers to the various results of parsing */ |
166 | struct p_context { |
167 | struct child_prog *child; |
168 | struct pipe *list_head; |
169 | struct pipe *pipe; |
170 | struct redir_struct *pending_redirect; |
171 | reserved_style w; |
172 | int old_flag; /* for figuring out valid reserved words */ |
173 | struct p_context *stack; |
174 | int type; /* define type of parser : ";$" common or special symbol */ |
175 | /* How about quoting status? */ |
176 | }; |
177 | |
178 | struct redir_struct { |
179 | redir_type type; /* type of redirection */ |
180 | int fd; /* file descriptor being redirected */ |
181 | int dup; /* -1, or file descriptor being duplicated */ |
182 | struct redir_struct *next; /* pointer to the next redirect in the list */ |
183 | glob_t word; /* *word.gl_pathv is the filename */ |
184 | }; |
185 | |
186 | struct child_prog { |
187 | pid_t pid; /* 0 if exited */ |
188 | char **argv; /* program name and arguments */ |
189 | struct pipe *group; /* if non-NULL, first in group or subshell */ |
190 | int subshell; /* flag, non-zero if group must be forked */ |
191 | struct redir_struct *redirects; /* I/O redirections */ |
192 | glob_t glob_result; /* result of parameter globbing */ |
193 | int is_stopped; /* is the program currently running? */ |
194 | struct pipe *family; /* pointer back to the child's parent pipe */ |
195 | int sp; /* number of SPECIAL_VAR_SYMBOL */ |
196 | int type; |
197 | }; |
198 | |
199 | struct pipe { |
200 | int jobid; /* job number */ |
201 | int num_progs; /* total number of programs in job */ |
202 | int running_progs; /* number of programs running */ |
203 | char *text; /* name of job */ |
204 | char *cmdbuf; /* buffer various argv's point into */ |
205 | pid_t pgrp; /* process group ID for the job */ |
206 | struct child_prog *progs; /* array of commands in pipe */ |
207 | struct pipe *next; /* to track background commands */ |
208 | int stopped_progs; /* number of programs alive, but stopped */ |
209 | int job_context; /* bitmask defining current context */ |
210 | pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */ |
211 | reserved_style r_mode; /* supports if, for, while, until */ |
212 | }; |
213 | |
214 | struct close_me { |
215 | int fd; |
216 | struct close_me *next; |
217 | }; |
218 | |
219 | struct variables { |
220 | char *name; |
221 | char *value; |
222 | int flg_export; |
223 | int flg_read_only; |
224 | struct variables *next; |
225 | }; |
226 | |
227 | /* globals, connect us to the outside world |
228 | * the first three support $?, $#, and $1 */ |
229 | static char **global_argv; |
230 | static int global_argc; |
231 | static int last_return_code; |
232 | extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */ |
233 | |
234 | /* "globals" within this file */ |
235 | static char *ifs; |
236 | static unsigned char map[256]; |
237 | static int fake_mode; |
238 | static int interactive; |
239 | static struct close_me *close_me_head; |
240 | static const char *cwd; |
241 | static struct pipe *job_list; |
242 | static unsigned int last_bg_pid; |
243 | static int last_jobid; |
244 | static unsigned int shell_terminal; |
245 | static char *PS1; |
246 | static char *PS2; |
247 | static struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 }; |
248 | static struct variables *top_vars = &shell_ver; |
249 | |
250 | |
251 | #define B_CHUNK (100) |
252 | #define B_NOSPAC 1 |
253 | |
254 | typedef struct { |
255 | char *data; |
256 | int length; |
257 | int maxlen; |
258 | int quote; |
259 | int nonnull; |
260 | } o_string; |
261 | #define NULL_O_STRING {NULL,0,0,0,0} |
262 | /* used for initialization: |
263 | o_string foo = NULL_O_STRING; */ |
264 | |
265 | /* I can almost use ordinary FILE *. Is open_memstream() universally |
266 | * available? Where is it documented? */ |
267 | struct in_str { |
268 | const char *p; |
269 | char peek_buf[2]; |
270 | int __promptme; |
271 | int promptmode; |
272 | FILE *file; |
273 | int (*get) (struct in_str *); |
274 | int (*peek) (struct in_str *); |
275 | }; |
276 | #define b_getch(input) ((input)->get(input)) |
277 | #define b_peek(input) ((input)->peek(input)) |
278 | |
279 | #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" |
280 | |
281 | struct built_in_command { |
282 | const char *cmd; /* name */ |
283 | const char *descr; /* description */ |
284 | int (*function) (struct child_prog *); /* function ptr */ |
285 | }; |
286 | |
287 | /* belongs in busybox.h */ |
288 | static int max(int a, int b) { |
289 | return (a>b)?a:b; |
290 | } |
291 | |
292 | /* This should be in utility.c */ |
293 | #ifdef DEBUG_SHELL |
294 | static void debug_printf(const char *format, ...) |
295 | { |
296 | va_list args; |
297 | va_start(args, format); |
298 | vfprintf(stderr, format, args); |
299 | va_end(args); |
300 | } |
301 | /* broken, of course, but OK for testing */ |
302 | static char *indenter(int i) |
303 | { |
304 | static char blanks[]=" "; |
305 | return &blanks[sizeof(blanks)-i-1]; |
306 | } |
307 | #else |
308 | #define debug_printf(...) do {;} while(0); |
309 | #endif |
310 | #define final_printf debug_printf |
311 | |
312 | static void __syntax(char *file, int line) { |
313 | bb_error_msg("syntax error %s:%d", file, line); |
314 | } |
315 | // NB: was __FILE__, but that produces full path sometimess, so... |
316 | #define syntax() __syntax("hush.c", __LINE__) |
317 | |
318 | /* Index of subroutines: */ |
319 | /* function prototypes for builtins */ |
320 | static int builtin_cd(struct child_prog *child); |
321 | static int builtin_env(struct child_prog *child); |
322 | static int builtin_eval(struct child_prog *child); |
323 | static int builtin_exec(struct child_prog *child); |
324 | static int builtin_exit(struct child_prog *child); |
325 | static int builtin_export(struct child_prog *child); |
326 | static int builtin_fg_bg(struct child_prog *child); |
327 | static int builtin_help(struct child_prog *child); |
328 | static int builtin_jobs(struct child_prog *child); |
329 | static int builtin_pwd(struct child_prog *child); |
330 | static int builtin_read(struct child_prog *child); |
331 | static int builtin_set(struct child_prog *child); |
332 | static int builtin_shift(struct child_prog *child); |
333 | static int builtin_source(struct child_prog *child); |
334 | static int builtin_umask(struct child_prog *child); |
335 | static int builtin_unset(struct child_prog *child); |
336 | static int builtin_not_written(struct child_prog *child); |
337 | /* o_string manipulation: */ |
338 | static int b_check_space(o_string *o, int len); |
339 | static int b_addchr(o_string *o, int ch); |
340 | static void b_reset(o_string *o); |
341 | static int b_addqchr(o_string *o, int ch, int quote); |
342 | static int b_adduint(o_string *o, unsigned int i); |
343 | /* in_str manipulations: */ |
344 | static int static_get(struct in_str *i); |
345 | static int static_peek(struct in_str *i); |
346 | static int file_get(struct in_str *i); |
347 | static int file_peek(struct in_str *i); |
348 | static void setup_file_in_str(struct in_str *i, FILE *f); |
349 | static void setup_string_in_str(struct in_str *i, const char *s); |
350 | /* close_me manipulations: */ |
351 | static void mark_open(int fd); |
352 | static void mark_closed(int fd); |
353 | static void close_all(void); |
354 | /* "run" the final data structures: */ |
355 | static int free_pipe_list(struct pipe *head, int indent); |
356 | static int free_pipe(struct pipe *pi, int indent); |
357 | /* really run the final data structures: */ |
358 | static int setup_redirects(struct child_prog *prog, int squirrel[]); |
359 | static int run_list_real(struct pipe *pi); |
360 | static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN; |
361 | static int run_pipe_real(struct pipe *pi); |
362 | /* extended glob support: */ |
363 | static int globhack(const char *src, int flags, glob_t *pglob); |
364 | static int glob_needed(const char *s); |
365 | static int xglob(o_string *dest, int flags, glob_t *pglob); |
366 | /* variable assignment: */ |
367 | static int is_assignment(const char *s); |
368 | /* data structure manipulation: */ |
369 | static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input); |
370 | static void initialize_context(struct p_context *ctx); |
371 | static int done_word(o_string *dest, struct p_context *ctx); |
372 | static int done_command(struct p_context *ctx); |
373 | static int done_pipe(struct p_context *ctx, pipe_style type); |
374 | /* primary string parsing: */ |
375 | static int redirect_dup_num(struct in_str *input); |
376 | static int redirect_opt_num(o_string *o); |
377 | static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end); |
378 | static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch); |
379 | static char *lookup_param(char *src); |
380 | static char *make_string(char **inp); |
381 | static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input); |
382 | static int parse_string(o_string *dest, struct p_context *ctx, const char *src); |
383 | static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger); |
384 | /* setup: */ |
385 | static int parse_stream_outer(struct in_str *inp, int flag); |
386 | static int parse_string_outer(const char *s, int flag); |
387 | static int parse_file_outer(FILE *f); |
388 | /* job management: */ |
389 | static int checkjobs(struct pipe* fg_pipe); |
390 | static void insert_bg_job(struct pipe *pi); |
391 | static void remove_bg_job(struct pipe *pi); |
392 | /* local variable support */ |
393 | static char **make_list_in(char **inp, char *name); |
394 | static char *insert_var_value(char *inp); |
395 | static char *get_local_var(const char *var); |
396 | static void unset_local_var(const char *name); |
397 | static int set_local_var(const char *s, int flg_export); |
398 | |
399 | /* Table of built-in functions. They can be forked or not, depending on |
400 | * context: within pipes, they fork. As simple commands, they do not. |
401 | * When used in non-forking context, they can change global variables |
402 | * in the parent shell process. If forked, of course they cannot. |
403 | * For example, 'unset foo | whatever' will parse and run, but foo will |
404 | * still be set at the end. */ |
405 | static const struct built_in_command bltins[] = { |
406 | {"bg", "Resume a job in the background", builtin_fg_bg}, |
407 | {"break", "Exit for, while or until loop", builtin_not_written}, |
408 | {"cd", "Change working directory", builtin_cd}, |
409 | {"continue", "Continue for, while or until loop", builtin_not_written}, |
410 | {"env", "Print all environment variables", builtin_env}, |
411 | {"eval", "Construct and run shell command", builtin_eval}, |
412 | {"exec", "Exec command, replacing this shell with the exec'd process", |
413 | builtin_exec}, |
414 | {"exit", "Exit from shell()", builtin_exit}, |
415 | {"export", "Set environment variable", builtin_export}, |
416 | {"fg", "Bring job into the foreground", builtin_fg_bg}, |
417 | {"jobs", "Lists the active jobs", builtin_jobs}, |
418 | {"pwd", "Print current directory", builtin_pwd}, |
419 | {"read", "Input environment variable", builtin_read}, |
420 | {"return", "Return from a function", builtin_not_written}, |
421 | {"set", "Set/unset shell local variables", builtin_set}, |
422 | {"shift", "Shift positional parameters", builtin_shift}, |
423 | {"trap", "Trap signals", builtin_not_written}, |
424 | {"ulimit","Controls resource limits", builtin_not_written}, |
425 | {"umask","Sets file creation mask", builtin_umask}, |
426 | {"unset", "Unset environment variable", builtin_unset}, |
427 | {".", "Source-in and run commands in a file", builtin_source}, |
428 | {"help", "List shell built-in commands", builtin_help}, |
429 | {NULL, NULL, NULL} |
430 | }; |
431 | |
432 | static const char *set_cwd(void) |
433 | { |
434 | if(cwd==bb_msg_unknown) |
435 | cwd = NULL; /* xgetcwd(arg) called free(arg) */ |
436 | cwd = xgetcwd((char *)cwd); |
437 | if (!cwd) |
438 | cwd = bb_msg_unknown; |
439 | return cwd; |
440 | } |
441 | |
442 | /* built-in 'eval' handler */ |
443 | static int builtin_eval(struct child_prog *child) |
444 | { |
445 | char *str = NULL; |
446 | int rcode = EXIT_SUCCESS; |
447 | |
448 | if (child->argv[1]) { |
449 | str = make_string(child->argv + 1); |
450 | parse_string_outer(str, FLAG_EXIT_FROM_LOOP | |
451 | FLAG_PARSE_SEMICOLON); |
452 | free(str); |
453 | rcode = last_return_code; |
454 | } |
455 | return rcode; |
456 | } |
457 | |
458 | /* built-in 'cd <path>' handler */ |
459 | static int builtin_cd(struct child_prog *child) |
460 | { |
461 | char *newdir; |
462 | if (child->argv[1] == NULL) |
463 | newdir = getenv("HOME"); |
464 | else |
465 | newdir = child->argv[1]; |
466 | if (chdir(newdir)) { |
467 | printf("cd: %s: %s\n", newdir, strerror(errno)); |
468 | return EXIT_FAILURE; |
469 | } |
470 | set_cwd(); |
471 | return EXIT_SUCCESS; |
472 | } |
473 | |
474 | /* built-in 'env' handler */ |
475 | static int builtin_env(struct child_prog *dummy ATTRIBUTE_UNUSED) |
476 | { |
477 | char **e = environ; |
478 | if (e == NULL) return EXIT_FAILURE; |
479 | for (; *e; e++) { |
480 | puts(*e); |
481 | } |
482 | return EXIT_SUCCESS; |
483 | } |
484 | |
485 | /* built-in 'exec' handler */ |
486 | static int builtin_exec(struct child_prog *child) |
487 | { |
488 | if (child->argv[1] == NULL) |
489 | return EXIT_SUCCESS; /* Really? */ |
490 | child->argv++; |
491 | pseudo_exec(child); |
492 | /* never returns */ |
493 | } |
494 | |
495 | /* built-in 'exit' handler */ |
496 | static int builtin_exit(struct child_prog *child) |
497 | { |
498 | if (child->argv[1] == NULL) |
499 | exit(last_return_code); |
500 | exit (atoi(child->argv[1])); |
501 | } |
502 | |
503 | /* built-in 'export VAR=value' handler */ |
504 | static int builtin_export(struct child_prog *child) |
505 | { |
506 | int res = 0; |
507 | char *name = child->argv[1]; |
508 | |
509 | if (name == NULL) { |
510 | return builtin_env(child); |
511 | } |
512 | |
513 | name = strdup(name); |
514 | |
515 | if(name) { |
516 | char *value = strchr(name, '='); |
517 | |
518 | if (!value) { |
519 | char *tmp; |
520 | /* They are exporting something without an =VALUE */ |
521 | |
522 | value = get_local_var(name); |
523 | if (value) { |
524 | size_t ln = strlen(name); |
525 | |
526 | tmp = realloc(name, ln+strlen(value)+2); |
527 | if(tmp==NULL) |
528 | res = -1; |
529 | else { |
530 | sprintf(tmp+ln, "=%s", value); |
531 | name = tmp; |
532 | } |
533 | } else { |
534 | /* bash does not return an error when trying to export |
535 | * an undefined variable. Do likewise. */ |
536 | res = 1; |
537 | } |
538 | } |
539 | } |
540 | if (res<0) |
541 | bb_perror_msg("export"); |
542 | else if(res==0) |
543 | res = set_local_var(name, 1); |
544 | else |
545 | res = 0; |
546 | free(name); |
547 | return res; |
548 | } |
549 | |
550 | /* built-in 'fg' and 'bg' handler */ |
551 | static int builtin_fg_bg(struct child_prog *child) |
552 | { |
553 | int i, jobnum; |
554 | struct pipe *pi=NULL; |
555 | |
556 | if (!interactive) |
557 | return EXIT_FAILURE; |
558 | /* If they gave us no args, assume they want the last backgrounded task */ |
559 | if (!child->argv[1]) { |
560 | for (pi = job_list; pi; pi = pi->next) { |
561 | if (pi->jobid == last_jobid) { |
562 | break; |
563 | } |
564 | } |
565 | if (!pi) { |
566 | bb_error_msg("%s: no current job", child->argv[0]); |
567 | return EXIT_FAILURE; |
568 | } |
569 | } else { |
570 | if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) { |
571 | bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]); |
572 | return EXIT_FAILURE; |
573 | } |
574 | for (pi = job_list; pi; pi = pi->next) { |
575 | if (pi->jobid == jobnum) { |
576 | break; |
577 | } |
578 | } |
579 | if (!pi) { |
580 | bb_error_msg("%s: %d: no such job", child->argv[0], jobnum); |
581 | return EXIT_FAILURE; |
582 | } |
583 | } |
584 | |
585 | if (*child->argv[0] == 'f') { |
586 | /* Put the job into the foreground. */ |
587 | tcsetpgrp(shell_terminal, pi->pgrp); |
588 | } |
589 | |
590 | /* Restart the processes in the job */ |
591 | for (i = 0; i < pi->num_progs; i++) |
592 | pi->progs[i].is_stopped = 0; |
593 | |
594 | if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) { |
595 | if (i == ESRCH) { |
596 | remove_bg_job(pi); |
597 | } else { |
598 | bb_perror_msg("kill (SIGCONT)"); |
599 | } |
600 | } |
601 | |
602 | pi->stopped_progs = 0; |
603 | return EXIT_SUCCESS; |
604 | } |
605 | |
606 | /* built-in 'help' handler */ |
607 | static int builtin_help(struct child_prog *dummy ATTRIBUTE_UNUSED) |
608 | { |
609 | const struct built_in_command *x; |
610 | |
611 | printf("\nBuilt-in commands:\n"); |
612 | printf("-------------------\n"); |
613 | for (x = bltins; x->cmd; x++) { |
614 | if (x->descr==NULL) |
615 | continue; |
616 | printf("%s\t%s\n", x->cmd, x->descr); |
617 | } |
618 | printf("\n\n"); |
619 | return EXIT_SUCCESS; |
620 | } |
621 | |
622 | /* built-in 'jobs' handler */ |
623 | static int builtin_jobs(struct child_prog *child ATTRIBUTE_UNUSED) |
624 | { |
625 | struct pipe *job; |
626 | char *status_string; |
627 | |
628 | for (job = job_list; job; job = job->next) { |
629 | if (job->running_progs == job->stopped_progs) |
630 | status_string = "Stopped"; |
631 | else |
632 | status_string = "Running"; |
633 | |
634 | printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text); |
635 | } |
636 | return EXIT_SUCCESS; |
637 | } |
638 | |
639 | |
640 | /* built-in 'pwd' handler */ |
641 | static int builtin_pwd(struct child_prog *dummy ATTRIBUTE_UNUSED) |
642 | { |
643 | puts(set_cwd()); |
644 | return EXIT_SUCCESS; |
645 | } |
646 | |
647 | /* built-in 'read VAR' handler */ |
648 | static int builtin_read(struct child_prog *child) |
649 | { |
650 | int res; |
651 | |
652 | if (child->argv[1]) { |
653 | char string[BUFSIZ]; |
654 | char *var = 0; |
655 | |
656 | string[0] = 0; /* In case stdin has only EOF */ |
657 | /* read string */ |
658 | fgets(string, sizeof(string), stdin); |
659 | chomp(string); |
660 | var = malloc(strlen(child->argv[1])+strlen(string)+2); |
661 | if(var) { |
662 | sprintf(var, "%s=%s", child->argv[1], string); |
663 | res = set_local_var(var, 0); |
664 | } else |
665 | res = -1; |
666 | if (res) |
667 | bb_perror_msg("read"); |
668 | free(var); /* So not move up to avoid breaking errno */ |
669 | return res; |
670 | } else { |
671 | do res=getchar(); while(res!='\n' && res!=EOF); |
672 | return 0; |
673 | } |
674 | } |
675 | |
676 | /* built-in 'set VAR=value' handler */ |
677 | static int builtin_set(struct child_prog *child) |
678 | { |
679 | char *temp = child->argv[1]; |
680 | struct variables *e; |
681 | |
682 | if (temp == NULL) |
683 | for(e = top_vars; e; e=e->next) |
684 | printf("%s=%s\n", e->name, e->value); |
685 | else |
686 | set_local_var(temp, 0); |
687 | |
688 | return EXIT_SUCCESS; |
689 | } |
690 | |
691 | |
692 | /* Built-in 'shift' handler */ |
693 | static int builtin_shift(struct child_prog *child) |
694 | { |
695 | int n=1; |
696 | if (child->argv[1]) { |
697 | n=atoi(child->argv[1]); |
698 | } |
699 | if (n>=0 && n<global_argc) { |
700 | /* XXX This probably breaks $0 */ |
701 | global_argc -= n; |
702 | global_argv += n; |
703 | return EXIT_SUCCESS; |
704 | } else { |
705 | return EXIT_FAILURE; |
706 | } |
707 | } |
708 | |
709 | /* Built-in '.' handler (read-in and execute commands from file) */ |
710 | static int builtin_source(struct child_prog *child) |
711 | { |
712 | FILE *input; |
713 | int status; |
714 | |
715 | if (child->argv[1] == NULL) |
716 | return EXIT_FAILURE; |
717 | |
718 | /* XXX search through $PATH is missing */ |
719 | input = fopen(child->argv[1], "r"); |
720 | if (!input) { |
721 | bb_error_msg("cannot open '%s'", child->argv[1]); |
722 | return EXIT_FAILURE; |
723 | } |
724 | |
725 | /* Now run the file */ |
726 | /* XXX argv and argc are broken; need to save old global_argv |
727 | * (pointer only is OK!) on this stack frame, |
728 | * set global_argv=child->argv+1, recurse, and restore. */ |
729 | mark_open(fileno(input)); |
730 | status = parse_file_outer(input); |
731 | mark_closed(fileno(input)); |
732 | fclose(input); |
733 | return status; |
734 | } |
735 | |
736 | static int builtin_umask(struct child_prog *child) |
737 | { |
738 | mode_t new_umask; |
739 | const char *arg = child->argv[1]; |
740 | char *end; |
741 | if (arg) { |
742 | new_umask=strtoul(arg, &end, 8); |
743 | if (*end!='\0' || end == arg) { |
744 | return EXIT_FAILURE; |
745 | } |
746 | } else { |
747 | printf("%.3o\n", (unsigned int) (new_umask=umask(0))); |
748 | } |
749 | umask(new_umask); |
750 | return EXIT_SUCCESS; |
751 | } |
752 | |
753 | /* built-in 'unset VAR' handler */ |
754 | static int builtin_unset(struct child_prog *child) |
755 | { |
756 | /* bash returned already true */ |
757 | unset_local_var(child->argv[1]); |
758 | return EXIT_SUCCESS; |
759 | } |
760 | |
761 | static int builtin_not_written(struct child_prog *child) |
762 | { |
763 | printf("builtin_%s not written\n",child->argv[0]); |
764 | return EXIT_FAILURE; |
765 | } |
766 | |
767 | static int b_check_space(o_string *o, int len) |
768 | { |
769 | /* It would be easy to drop a more restrictive policy |
770 | * in here, such as setting a maximum string length */ |
771 | if (o->length + len > o->maxlen) { |
772 | char *old_data = o->data; |
773 | /* assert (data == NULL || o->maxlen != 0); */ |
774 | o->maxlen += max(2*len, B_CHUNK); |
775 | o->data = realloc(o->data, 1 + o->maxlen); |
776 | if (o->data == NULL) { |
777 | free(old_data); |
778 | } |
779 | } |
780 | return o->data == NULL; |
781 | } |
782 | |
783 | static int b_addchr(o_string *o, int ch) |
784 | { |
785 | debug_printf("b_addchr: %c %d %p\n", ch, o->length, o); |
786 | if (b_check_space(o, 1)) return B_NOSPAC; |
787 | o->data[o->length] = ch; |
788 | o->length++; |
789 | o->data[o->length] = '\0'; |
790 | return 0; |
791 | } |
792 | |
793 | static void b_reset(o_string *o) |
794 | { |
795 | o->length = 0; |
796 | o->nonnull = 0; |
797 | if (o->data != NULL) *o->data = '\0'; |
798 | } |
799 | |
800 | static void b_free(o_string *o) |
801 | { |
802 | b_reset(o); |
803 | free(o->data); |
804 | o->data = NULL; |
805 | o->maxlen = 0; |
806 | } |
807 | |
808 | /* My analysis of quoting semantics tells me that state information |
809 | * is associated with a destination, not a source. |
810 | */ |
811 | static int b_addqchr(o_string *o, int ch, int quote) |
812 | { |
813 | if (quote && strchr("*?[\\",ch)) { |
814 | int rc; |
815 | rc = b_addchr(o, '\\'); |
816 | if (rc) return rc; |
817 | } |
818 | return b_addchr(o, ch); |
819 | } |
820 | |
821 | /* belongs in utility.c */ |
822 | static char *simple_itoa(unsigned int i) |
823 | { |
824 | /* 21 digits plus null terminator, good for 64-bit or smaller ints */ |
825 | static char local[22]; |
826 | char *p = &local[21]; |
827 | *p-- = '\0'; |
828 | do { |
829 | *p-- = '0' + i % 10; |
830 | i /= 10; |
831 | } while (i > 0); |
832 | return p + 1; |
833 | } |
834 | |
835 | static int b_adduint(o_string *o, unsigned int i) |
836 | { |
837 | int r; |
838 | char *p = simple_itoa(i); |
839 | /* no escape checking necessary */ |
840 | do r=b_addchr(o, *p++); while (r==0 && *p); |
841 | return r; |
842 | } |
843 | |
844 | static int static_get(struct in_str *i) |
845 | { |
846 | int ch=*i->p++; |
847 | if (ch=='\0') return EOF; |
848 | return ch; |
849 | } |
850 | |
851 | static int static_peek(struct in_str *i) |
852 | { |
853 | return *i->p; |
854 | } |
855 | |
856 | static void cmdedit_set_initial_prompt(void) |
857 | { |
858 | #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT |
859 | PS1 = NULL; |
860 | #else |
861 | PS1 = getenv("PS1"); |
862 | if(PS1==0) |
863 | PS1 = "\\w \\$ "; |
864 | #endif |
865 | } |
866 | |
867 | static void setup_prompt_string(int promptmode, char **prompt_str) |
868 | { |
869 | debug_printf("setup_prompt_string %d ",promptmode); |
870 | #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT |
871 | /* Set up the prompt */ |
872 | if (promptmode == 1) { |
873 | free(PS1); |
874 | PS1=xmalloc(strlen(cwd)+4); |
875 | sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# "); |
876 | *prompt_str = PS1; |
877 | } else { |
878 | *prompt_str = PS2; |
879 | } |
880 | #else |
881 | *prompt_str = (promptmode==1)? PS1 : PS2; |
882 | #endif |
883 | debug_printf("result %s\n",*prompt_str); |
884 | } |
885 | |
886 | static void get_user_input(struct in_str *i) |
887 | { |
888 | char *prompt_str; |
889 | static char the_command[BUFSIZ]; |
890 | |
891 | setup_prompt_string(i->promptmode, &prompt_str); |
892 | #ifdef CONFIG_FEATURE_COMMAND_EDITING |
893 | /* |
894 | ** enable command line editing only while a command line |
895 | ** is actually being read; otherwise, we'll end up bequeathing |
896 | ** atexit() handlers and other unwanted stuff to our |
897 | ** child processes (rob@sysgo.de) |
898 | */ |
899 | cmdedit_read_input(prompt_str, the_command); |
900 | #else |
901 | fputs(prompt_str, stdout); |
902 | fflush(stdout); |
903 | the_command[0]=fgetc(i->file); |
904 | the_command[1]='\0'; |
905 | #endif |
906 | fflush(stdout); |
907 | i->p = the_command; |
908 | } |
909 | |
910 | /* This is the magic location that prints prompts |
911 | * and gets data back from the user */ |
912 | static int file_get(struct in_str *i) |
913 | { |
914 | int ch; |
915 | |
916 | ch = 0; |
917 | /* If there is data waiting, eat it up */ |
918 | if (i->p && *i->p) { |
919 | ch=*i->p++; |
920 | } else { |
921 | /* need to double check i->file because we might be doing something |
922 | * more complicated by now, like sourcing or substituting. */ |
923 | if (i->__promptme && interactive && i->file == stdin) { |
924 | while(! i->p || (interactive && strlen(i->p)==0) ) { |
925 | get_user_input(i); |
926 | } |
927 | i->promptmode=2; |
928 | i->__promptme = 0; |
929 | if (i->p && *i->p) { |
930 | ch=*i->p++; |
931 | } |
932 | } else { |
933 | ch = fgetc(i->file); |
934 | } |
935 | |
936 | debug_printf("b_getch: got a %d\n", ch); |
937 | } |
938 | if (ch == '\n') i->__promptme=1; |
939 | return ch; |
940 | } |
941 | |
942 | /* All the callers guarantee this routine will never be |
943 | * used right after a newline, so prompting is not needed. |
944 | */ |
945 | static int file_peek(struct in_str *i) |
946 | { |
947 | if (i->p && *i->p) { |
948 | return *i->p; |
949 | } else { |
950 | i->peek_buf[0] = fgetc(i->file); |
951 | i->peek_buf[1] = '\0'; |
952 | i->p = i->peek_buf; |
953 | debug_printf("b_peek: got a %d\n", *i->p); |
954 | return *i->p; |
955 | } |
956 | } |
957 | |
958 | static void setup_file_in_str(struct in_str *i, FILE *f) |
959 | { |
960 | i->peek = file_peek; |
961 | i->get = file_get; |
962 | i->__promptme=1; |
963 | i->promptmode=1; |
964 | i->file = f; |
965 | i->p = NULL; |
966 | } |
967 | |
968 | static void setup_string_in_str(struct in_str *i, const char *s) |
969 | { |
970 | i->peek = static_peek; |
971 | i->get = static_get; |
972 | i->__promptme=1; |
973 | i->promptmode=1; |
974 | i->p = s; |
975 | } |
976 | |
977 | static void mark_open(int fd) |
978 | { |
979 | struct close_me *new = xmalloc(sizeof(struct close_me)); |
980 | new->fd = fd; |
981 | new->next = close_me_head; |
982 | close_me_head = new; |
983 | } |
984 | |
985 | static void mark_closed(int fd) |
986 | { |
987 | struct close_me *tmp; |
988 | if (close_me_head == NULL || close_me_head->fd != fd) |
989 | bb_error_msg_and_die("corrupt close_me"); |
990 | tmp = close_me_head; |
991 | close_me_head = close_me_head->next; |
992 | free(tmp); |
993 | } |
994 | |
995 | static void close_all(void) |
996 | { |
997 | struct close_me *c; |
998 | for (c=close_me_head; c; c=c->next) { |
999 | close(c->fd); |
1000 | } |
1001 | close_me_head = NULL; |
1002 | } |
1003 | |
1004 | /* squirrel != NULL means we squirrel away copies of stdin, stdout, |
1005 | * and stderr if they are redirected. */ |
1006 | static int setup_redirects(struct child_prog *prog, int squirrel[]) |
1007 | { |
1008 | int openfd, mode; |
1009 | struct redir_struct *redir; |
1010 | |
1011 | for (redir=prog->redirects; redir; redir=redir->next) { |
1012 | if (redir->dup == -1 && redir->word.gl_pathv == NULL) { |
1013 | /* something went wrong in the parse. Pretend it didn't happen */ |
1014 | continue; |
1015 | } |
1016 | if (redir->dup == -1) { |
1017 | mode=redir_table[redir->type].mode; |
1018 | openfd = open(redir->word.gl_pathv[0], mode, 0666); |
1019 | if (openfd < 0) { |
1020 | /* this could get lost if stderr has been redirected, but |
1021 | bash and ash both lose it as well (though zsh doesn't!) */ |
1022 | bb_perror_msg("error opening %s", redir->word.gl_pathv[0]); |
1023 | return 1; |
1024 | } |
1025 | } else { |
1026 | openfd = redir->dup; |
1027 | } |
1028 | |
1029 | if (openfd != redir->fd) { |
1030 | if (squirrel && redir->fd < 3) { |
1031 | squirrel[redir->fd] = dup(redir->fd); |
1032 | } |
1033 | if (openfd == -3) { |
1034 | close(openfd); |
1035 | } else { |
1036 | dup2(openfd, redir->fd); |
1037 | if (redir->dup == -1) |
1038 | close (openfd); |
1039 | } |
1040 | } |
1041 | } |
1042 | return 0; |
1043 | } |
1044 | |
1045 | static void restore_redirects(int squirrel[]) |
1046 | { |
1047 | int i, fd; |
1048 | for (i=0; i<3; i++) { |
1049 | fd = squirrel[i]; |
1050 | if (fd != -1) { |
1051 | /* No error checking. I sure wouldn't know what |
1052 | * to do with an error if I found one! */ |
1053 | dup2(fd, i); |
1054 | close(fd); |
1055 | } |
1056 | } |
1057 | } |
1058 | |
1059 | /* never returns */ |
1060 | /* XXX no exit() here. If you don't exec, use _exit instead. |
1061 | * The at_exit handlers apparently confuse the calling process, |
1062 | * in particular stdin handling. Not sure why? */ |
1063 | static void pseudo_exec(struct child_prog *child) |
1064 | { |
1065 | int i, rcode; |
1066 | char *p; |
1067 | const struct built_in_command *x; |
1068 | if (child->argv) { |
1069 | for (i=0; is_assignment(child->argv[i]); i++) { |
1070 | debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]); |
1071 | p = insert_var_value(child->argv[i]); |
1072 | putenv(strdup(p)); |
1073 | if (p != child->argv[i]) free(p); |
1074 | } |
1075 | child->argv+=i; /* XXX this hack isn't so horrible, since we are about |
1076 | to exit, and therefore don't need to keep data |
1077 | structures consistent for free() use. */ |
1078 | /* If a variable is assigned in a forest, and nobody listens, |
1079 | * was it ever really set? |
1080 | */ |
1081 | if (child->argv[0] == NULL) { |
1082 | _exit(EXIT_SUCCESS); |
1083 | } |
1084 | |
1085 | /* |
1086 | * Check if the command matches any of the builtins. |
1087 | * Depending on context, this might be redundant. But it's |
1088 | * easier to waste a few CPU cycles than it is to figure out |
1089 | * if this is one of those cases. |
1090 | */ |
1091 | for (x = bltins; x->cmd; x++) { |
1092 | if (strcmp(child->argv[0], x->cmd) == 0 ) { |
1093 | debug_printf("builtin exec %s\n", child->argv[0]); |
1094 | rcode = x->function(child); |
1095 | fflush(stdout); |
1096 | _exit(rcode); |
1097 | } |
1098 | } |
1099 | |
1100 | /* Check if the command matches any busybox internal commands |
1101 | * ("applets") here. |
1102 | * FIXME: This feature is not 100% safe, since |
1103 | * BusyBox is not fully reentrant, so we have no guarantee the things |
1104 | * from the .bss are still zeroed, or that things from .data are still |
1105 | * at their defaults. We could exec ourself from /proc/self/exe, but I |
1106 | * really dislike relying on /proc for things. We could exec ourself |
1107 | * from global_argv[0], but if we are in a chroot, we may not be able |
1108 | * to find ourself... */ |
1109 | #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL |
1110 | { |
1111 | int argc_l; |
1112 | char** argv_l=child->argv; |
1113 | char *name = child->argv[0]; |
1114 | |
1115 | /* Count argc for use in a second... */ |
1116 | for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++); |
1117 | optind = 1; |
1118 | debug_printf("running applet %s\n", name); |
1119 | run_applet_by_name(name, argc_l, child->argv); |
1120 | } |
1121 | #endif |
1122 | debug_printf("exec of %s\n",child->argv[0]); |
1123 | execvp(child->argv[0],child->argv); |
1124 | bb_perror_msg("cannot exec: %s",child->argv[0]); |
1125 | _exit(1); |
1126 | } else if (child->group) { |
1127 | debug_printf("runtime nesting to group\n"); |
1128 | interactive=0; /* crucial!!!! */ |
1129 | rcode = run_list_real(child->group); |
1130 | /* OK to leak memory by not calling free_pipe_list, |
1131 | * since this process is about to exit */ |
1132 | _exit(rcode); |
1133 | } else { |
1134 | /* Can happen. See what bash does with ">foo" by itself. */ |
1135 | debug_printf("trying to pseudo_exec null command\n"); |
1136 | _exit(EXIT_SUCCESS); |
1137 | } |
1138 | } |
1139 | |
1140 | static void insert_bg_job(struct pipe *pi) |
1141 | { |
1142 | struct pipe *thejob; |
1143 | |
1144 | /* Linear search for the ID of the job to use */ |
1145 | pi->jobid = 1; |
1146 | for (thejob = job_list; thejob; thejob = thejob->next) |
1147 | if (thejob->jobid >= pi->jobid) |
1148 | pi->jobid = thejob->jobid + 1; |
1149 | |
1150 | /* add thejob to the list of running jobs */ |
1151 | if (!job_list) { |
1152 | thejob = job_list = xmalloc(sizeof(*thejob)); |
1153 | } else { |
1154 | for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */; |
1155 | thejob->next = xmalloc(sizeof(*thejob)); |
1156 | thejob = thejob->next; |
1157 | } |
1158 | |
1159 | /* physically copy the struct job */ |
1160 | memcpy(thejob, pi, sizeof(struct pipe)); |
1161 | thejob->next = NULL; |
1162 | thejob->running_progs = thejob->num_progs; |
1163 | thejob->stopped_progs = 0; |
1164 | thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */ |
1165 | |
1166 | //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) |
1167 | { |
1168 | char *bar=thejob->text; |
1169 | char **foo=pi->progs[0].argv; |
1170 | while(foo && *foo) { |
1171 | bar += sprintf(bar, "%s ", *foo++); |
1172 | } |
1173 | } |
1174 | |
1175 | /* we don't wait for background thejobs to return -- append it |
1176 | to the list of backgrounded thejobs and leave it alone */ |
1177 | printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid); |
1178 | last_bg_pid = thejob->progs[0].pid; |
1179 | last_jobid = thejob->jobid; |
1180 | } |
1181 | |
1182 | /* remove a backgrounded job */ |
1183 | static void remove_bg_job(struct pipe *pi) |
1184 | { |
1185 | struct pipe *prev_pipe; |
1186 | |
1187 | if (pi == job_list) { |
1188 | job_list = pi->next; |
1189 | } else { |
1190 | prev_pipe = job_list; |
1191 | while (prev_pipe->next != pi) |
1192 | prev_pipe = prev_pipe->next; |
1193 | prev_pipe->next = pi->next; |
1194 | } |
1195 | if (job_list) |
1196 | last_jobid = job_list->jobid; |
1197 | else |
1198 | last_jobid = 0; |
1199 | |
1200 | pi->stopped_progs = 0; |
1201 | free_pipe(pi, 0); |
1202 | free(pi); |
1203 | } |
1204 | |
1205 | /* Checks to see if any processes have exited -- if they |
1206 | have, figure out why and see if a job has completed */ |
1207 | static int checkjobs(struct pipe* fg_pipe) |
1208 | { |
1209 | int attributes; |
1210 | int status; |
1211 | int prognum = 0; |
1212 | struct pipe *pi; |
1213 | pid_t childpid; |
1214 | |
1215 | attributes = WUNTRACED; |
1216 | if (fg_pipe==NULL) { |
1217 | attributes |= WNOHANG; |
1218 | } |
1219 | |
1220 | while ((childpid = waitpid(-1, &status, attributes)) > 0) { |
1221 | if (fg_pipe) { |
1222 | int i, rcode = 0; |
1223 | for (i=0; i < fg_pipe->num_progs; i++) { |
1224 | if (fg_pipe->progs[i].pid == childpid) { |
1225 | if (i==fg_pipe->num_progs-1) |
1226 | rcode=WEXITSTATUS(status); |
1227 | (fg_pipe->num_progs)--; |
1228 | return rcode; |
1229 | } |
1230 | } |
1231 | } |
1232 | |
1233 | for (pi = job_list; pi; pi = pi->next) { |
1234 | prognum = 0; |
1235 | while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) { |
1236 | prognum++; |
1237 | } |
1238 | if (prognum < pi->num_progs) |
1239 | break; |
1240 | } |
1241 | |
1242 | if(pi==NULL) { |
1243 | debug_printf("checkjobs: pid %d was not in our list!\n", childpid); |
1244 | continue; |
1245 | } |
1246 | |
1247 | if (WIFEXITED(status) || WIFSIGNALED(status)) { |
1248 | /* child exited */ |
1249 | pi->running_progs--; |
1250 | pi->progs[prognum].pid = 0; |
1251 | |
1252 | if (!pi->running_progs) { |
1253 | printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text); |
1254 | remove_bg_job(pi); |
1255 | } |
1256 | } else { |
1257 | /* child stopped */ |
1258 | pi->stopped_progs++; |
1259 | pi->progs[prognum].is_stopped = 1; |
1260 | } |
1261 | } |
1262 | |
1263 | if (childpid == -1 && errno != ECHILD) |
1264 | bb_perror_msg("waitpid"); |
1265 | |
1266 | /* move the shell to the foreground */ |
1267 | //if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) |
1268 | // bb_perror_msg("tcsetpgrp-2"); |
1269 | return -1; |
1270 | } |
1271 | |
1272 | /* run_pipe_real() starts all the jobs, but doesn't wait for anything |
1273 | * to finish. See checkjobs(). |
1274 | * |
1275 | * return code is normally -1, when the caller has to wait for children |
1276 | * to finish to determine the exit status of the pipe. If the pipe |
1277 | * is a simple builtin command, however, the action is done by the |
1278 | * time run_pipe_real returns, and the exit code is provided as the |
1279 | * return value. |
1280 | * |
1281 | * The input of the pipe is always stdin, the output is always |
1282 | * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus, |
1283 | * because it tries to avoid running the command substitution in |
1284 | * subshell, when that is in fact necessary. The subshell process |
1285 | * now has its stdout directed to the input of the appropriate pipe, |
1286 | * so this routine is noticeably simpler. |
1287 | */ |
1288 | static int run_pipe_real(struct pipe *pi) |
1289 | { |
1290 | int i; |
1291 | int nextin, nextout; |
1292 | int pipefds[2]; /* pipefds[0] is for reading */ |
1293 | struct child_prog *child; |
1294 | const struct built_in_command *x; |
1295 | char *p; |
1296 | |
1297 | nextin = 0; |
1298 | pi->pgrp = -1; |
1299 | |
1300 | /* Check if this is a simple builtin (not part of a pipe). |
1301 | * Builtins within pipes have to fork anyway, and are handled in |
1302 | * pseudo_exec. "echo foo | read bar" doesn't work on bash, either. |
1303 | */ |
1304 | child = & (pi->progs[0]); |
1305 | if (pi->num_progs == 1 && child->group && child->subshell == 0) { |
1306 | int squirrel[] = {-1, -1, -1}; |
1307 | int rcode; |
1308 | debug_printf("non-subshell grouping\n"); |
1309 | setup_redirects(child, squirrel); |
1310 | /* XXX could we merge code with following builtin case, |
1311 | * by creating a pseudo builtin that calls run_list_real? */ |
1312 | rcode = run_list_real(child->group); |
1313 | restore_redirects(squirrel); |
1314 | return rcode; |
1315 | } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) { |
1316 | for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ } |
1317 | if (i!=0 && child->argv[i]==NULL) { |
1318 | /* assignments, but no command: set the local environment */ |
1319 | for (i=0; child->argv[i]!=NULL; i++) { |
1320 | |
1321 | /* Ok, this case is tricky. We have to decide if this is a |
1322 | * local variable, or an already exported variable. If it is |
1323 | * already exported, we have to export the new value. If it is |
1324 | * not exported, we need only set this as a local variable. |
1325 | * This junk is all to decide whether or not to export this |
1326 | * variable. */ |
1327 | int export_me=0; |
1328 | char *name, *value; |
1329 | name = xstrdup(child->argv[i]); |
1330 | debug_printf("Local environment set: %s\n", name); |
1331 | value = strchr(name, '='); |
1332 | if (value) |
1333 | *value=0; |
1334 | if ( get_local_var(name)) { |
1335 | export_me=1; |
1336 | } |
1337 | free(name); |
1338 | p = insert_var_value(child->argv[i]); |
1339 | set_local_var(p, export_me); |
1340 | if (p != child->argv[i]) free(p); |
1341 | } |
1342 | return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */ |
1343 | } |
1344 | for (i = 0; is_assignment(child->argv[i]); i++) { |
1345 | p = insert_var_value(child->argv[i]); |
1346 | putenv(strdup(p)); |
1347 | if (p != child->argv[i]) { |
1348 | child->sp--; |
1349 | free(p); |
1350 | } |
1351 | } |
1352 | if (child->sp) { |
1353 | char * str = NULL; |
1354 | |
1355 | str = make_string((child->argv + i)); |
1356 | parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING); |
1357 | free(str); |
1358 | return last_return_code; |
1359 | } |
1360 | for (x = bltins; x->cmd; x++) { |
1361 | if (strcmp(child->argv[i], x->cmd) == 0 ) { |
1362 | int squirrel[] = {-1, -1, -1}; |
1363 | int rcode; |
1364 | if (x->function == builtin_exec && child->argv[i+1]==NULL) { |
1365 | debug_printf("magic exec\n"); |
1366 | setup_redirects(child,NULL); |
1367 | return EXIT_SUCCESS; |
1368 | } |
1369 | debug_printf("builtin inline %s\n", child->argv[0]); |
1370 | /* XXX setup_redirects acts on file descriptors, not FILEs. |
1371 | * This is perfect for work that comes after exec(). |
1372 | * Is it really safe for inline use? Experimentally, |
1373 | * things seem to work with glibc. */ |
1374 | setup_redirects(child, squirrel); |
1375 | child->argv+=i; /* XXX horrible hack */ |
1376 | rcode = x->function(child); |
1377 | child->argv-=i; /* XXX restore hack so free() can work right */ |
1378 | restore_redirects(squirrel); |
1379 | return rcode; |
1380 | } |
1381 | } |
1382 | } |
1383 | |
1384 | for (i = 0; i < pi->num_progs; i++) { |
1385 | child = & (pi->progs[i]); |
1386 | |
1387 | /* pipes are inserted between pairs of commands */ |
1388 | if ((i + 1) < pi->num_progs) { |
1389 | if (pipe(pipefds)<0) bb_perror_msg_and_die("pipe"); |
1390 | nextout = pipefds[1]; |
1391 | } else { |
1392 | nextout=1; |
1393 | pipefds[0] = -1; |
1394 | } |
1395 | |
1396 | /* XXX test for failed fork()? */ |
1397 | #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__) |
1398 | if (!(child->pid = fork())) |
1399 | #else |
1400 | if (!(child->pid = vfork())) |
1401 | #endif |
1402 | { |
1403 | /* Set the handling for job control signals back to the default. */ |
1404 | signal(SIGINT, SIG_DFL); |
1405 | signal(SIGQUIT, SIG_DFL); |
1406 | signal(SIGTERM, SIG_DFL); |
1407 | signal(SIGTSTP, SIG_DFL); |
1408 | signal(SIGTTIN, SIG_DFL); |
1409 | signal(SIGTTOU, SIG_DFL); |
1410 | signal(SIGCHLD, SIG_DFL); |
1411 | |
1412 | close_all(); |
1413 | |
1414 | if (nextin != 0) { |
1415 | dup2(nextin, 0); |
1416 | close(nextin); |
1417 | } |
1418 | if (nextout != 1) { |
1419 | dup2(nextout, 1); |
1420 | close(nextout); |
1421 | } |
1422 | if (pipefds[0]!=-1) { |
1423 | close(pipefds[0]); /* opposite end of our output pipe */ |
1424 | } |
1425 | |
1426 | /* Like bash, explicit redirects override pipes, |
1427 | * and the pipe fd is available for dup'ing. */ |
1428 | setup_redirects(child,NULL); |
1429 | |
1430 | if (interactive && pi->followup!=PIPE_BG) { |
1431 | /* If we (the child) win the race, put ourselves in the process |
1432 | * group whose leader is the first process in this pipe. */ |
1433 | if (pi->pgrp < 0) { |
1434 | pi->pgrp = getpid(); |
1435 | } |
1436 | if (setpgid(0, pi->pgrp) == 0) { |
1437 | tcsetpgrp(2, pi->pgrp); |
1438 | } |
1439 | } |
1440 | |
1441 | pseudo_exec(child); |
1442 | } |
1443 | |
1444 | |
1445 | /* put our child in the process group whose leader is the |
1446 | first process in this pipe */ |
1447 | if (pi->pgrp < 0) { |
1448 | pi->pgrp = child->pid; |
1449 | } |
1450 | /* Don't check for errors. The child may be dead already, |
1451 | * in which case setpgid returns error code EACCES. */ |
1452 | setpgid(child->pid, pi->pgrp); |
1453 | |
1454 | if (nextin != 0) |
1455 | close(nextin); |
1456 | if (nextout != 1) |
1457 | close(nextout); |
1458 | |
1459 | /* If there isn't another process, nextin is garbage |
1460 | but it doesn't matter */ |
1461 | nextin = pipefds[0]; |
1462 | } |
1463 | return -1; |
1464 | } |
1465 | |
1466 | static int run_list_real(struct pipe *pi) |
1467 | { |
1468 | char *save_name = NULL; |
1469 | char **list = NULL; |
1470 | char **save_list = NULL; |
1471 | struct pipe *rpipe; |
1472 | int flag_rep = 0; |
1473 | int save_num_progs; |
1474 | int rcode=0, flag_skip=1; |
1475 | int flag_restore = 0; |
1476 | int if_code=0, next_if_code=0; /* need double-buffer to handle elif */ |
1477 | reserved_style rmode, skip_more_in_this_rmode=RES_XXXX; |
1478 | /* check syntax for "for" */ |
1479 | for (rpipe = pi; rpipe; rpipe = rpipe->next) { |
1480 | if ((rpipe->r_mode == RES_IN || |
1481 | rpipe->r_mode == RES_FOR) && |
1482 | (rpipe->next == NULL)) { |
1483 | syntax(); |
1484 | return 1; |
1485 | } |
1486 | if ((rpipe->r_mode == RES_IN && |
1487 | (rpipe->next->r_mode == RES_IN && |
1488 | rpipe->next->progs->argv != NULL))|| |
1489 | (rpipe->r_mode == RES_FOR && |
1490 | rpipe->next->r_mode != RES_IN)) { |
1491 | syntax(); |
1492 | return 1; |
1493 | } |
1494 | } |
1495 | for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) { |
1496 | if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL || |
1497 | pi->r_mode == RES_FOR) { |
1498 | flag_restore = 0; |
1499 | if (!rpipe) { |
1500 | flag_rep = 0; |
1501 | rpipe = pi; |
1502 | } |
1503 | } |
1504 | rmode = pi->r_mode; |
1505 | 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); |
1506 | if (rmode == skip_more_in_this_rmode && flag_skip) { |
1507 | if (pi->followup == PIPE_SEQ) flag_skip=0; |
1508 | continue; |
1509 | } |
1510 | flag_skip = 1; |
1511 | skip_more_in_this_rmode = RES_XXXX; |
1512 | if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code; |
1513 | if (rmode == RES_THEN && if_code) continue; |
1514 | if (rmode == RES_ELSE && !if_code) continue; |
1515 | if (rmode == RES_ELIF && !if_code) break; |
1516 | if (rmode == RES_FOR && pi->num_progs) { |
1517 | if (!list) { |
1518 | /* if no variable values after "in" we skip "for" */ |
1519 | if (!pi->next->progs->argv) continue; |
1520 | /* create list of variable values */ |
1521 | list = make_list_in(pi->next->progs->argv, |
1522 | pi->progs->argv[0]); |
1523 | save_list = list; |
1524 | save_name = pi->progs->argv[0]; |
1525 | pi->progs->argv[0] = NULL; |
1526 | flag_rep = 1; |
1527 | } |
1528 | if (!(*list)) { |
1529 | free(pi->progs->argv[0]); |
1530 | free(save_list); |
1531 | list = NULL; |
1532 | flag_rep = 0; |
1533 | pi->progs->argv[0] = save_name; |
1534 | pi->progs->glob_result.gl_pathv[0] = |
1535 | pi->progs->argv[0]; |
1536 | continue; |
1537 | } else { |
1538 | /* insert new value from list for variable */ |
1539 | if (pi->progs->argv[0]) |
1540 | free(pi->progs->argv[0]); |
1541 | pi->progs->argv[0] = *list++; |
1542 | pi->progs->glob_result.gl_pathv[0] = |
1543 | pi->progs->argv[0]; |
1544 | } |
1545 | } |
1546 | if (rmode == RES_IN) continue; |
1547 | if (rmode == RES_DO) { |
1548 | if (!flag_rep) continue; |
1549 | } |
1550 | if ((rmode == RES_DONE)) { |
1551 | if (flag_rep) { |
1552 | flag_restore = 1; |
1553 | } else { |
1554 | rpipe = NULL; |
1555 | } |
1556 | } |
1557 | if (pi->num_progs == 0) continue; |
1558 | save_num_progs = pi->num_progs; /* save number of programs */ |
1559 | rcode = run_pipe_real(pi); |
1560 | debug_printf("run_pipe_real returned %d\n",rcode); |
1561 | if (rcode!=-1) { |
1562 | /* We only ran a builtin: rcode was set by the return value |
1563 | * of run_pipe_real(), and we don't need to wait for anything. */ |
1564 | } else if (pi->followup==PIPE_BG) { |
1565 | /* XXX check bash's behavior with nontrivial pipes */ |
1566 | /* XXX compute jobid */ |
1567 | /* XXX what does bash do with attempts to background builtins? */ |
1568 | insert_bg_job(pi); |
1569 | rcode = EXIT_SUCCESS; |
1570 | } else { |
1571 | if (interactive) { |
1572 | /* move the new process group into the foreground */ |
1573 | if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY) |
1574 | bb_perror_msg("tcsetpgrp-3"); |
1575 | rcode = checkjobs(pi); |
1576 | /* move the shell to the foreground */ |
1577 | if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY) |
1578 | bb_perror_msg("tcsetpgrp-4"); |
1579 | } else { |
1580 | rcode = checkjobs(pi); |
1581 | } |
1582 | debug_printf("checkjobs returned %d\n",rcode); |
1583 | } |
1584 | last_return_code=rcode; |
1585 | pi->num_progs = save_num_progs; /* restore number of programs */ |
1586 | if ( rmode == RES_IF || rmode == RES_ELIF ) |
1587 | next_if_code=rcode; /* can be overwritten a number of times */ |
1588 | if (rmode == RES_WHILE) |
1589 | flag_rep = !last_return_code; |
1590 | if (rmode == RES_UNTIL) |
1591 | flag_rep = last_return_code; |
1592 | if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) || |
1593 | (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) ) |
1594 | skip_more_in_this_rmode=rmode; |
1595 | checkjobs(NULL); |
1596 | } |
1597 | return rcode; |
1598 | } |
1599 | |
1600 | /* return code is the exit status of the pipe */ |
1601 | static int free_pipe(struct pipe *pi, int indent) |
1602 | { |
1603 | char **p; |
1604 | struct child_prog *child; |
1605 | struct redir_struct *r, *rnext; |
1606 | int a, i, ret_code=0; |
1607 | |
1608 | if (pi->stopped_progs > 0) |
1609 | return ret_code; |
1610 | final_printf("%s run pipe: (pid %d)\n",indenter(indent),getpid()); |
1611 | for (i=0; i<pi->num_progs; i++) { |
1612 | child = &pi->progs[i]; |
1613 | final_printf("%s command %d:\n",indenter(indent),i); |
1614 | if (child->argv) { |
1615 | for (a=0,p=child->argv; *p; a++,p++) { |
1616 | final_printf("%s argv[%d] = %s\n",indenter(indent),a,*p); |
1617 | } |
1618 | globfree(&child->glob_result); |
1619 | child->argv=NULL; |
1620 | } else if (child->group) { |
1621 | final_printf("%s begin group (subshell:%d)\n",indenter(indent), child->subshell); |
1622 | ret_code = free_pipe_list(child->group,indent+3); |
1623 | final_printf("%s end group\n",indenter(indent)); |
1624 | } else { |
1625 | final_printf("%s (nil)\n",indenter(indent)); |
1626 | } |
1627 | for (r=child->redirects; r; r=rnext) { |
1628 | final_printf("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip); |
1629 | if (r->dup == -1) { |
1630 | /* guard against the case >$FOO, where foo is unset or blank */ |
1631 | if (r->word.gl_pathv) { |
1632 | final_printf(" %s\n", *r->word.gl_pathv); |
1633 | globfree(&r->word); |
1634 | } |
1635 | } else { |
1636 | final_printf("&%d\n", r->dup); |
1637 | } |
1638 | rnext=r->next; |
1639 | free(r); |
1640 | } |
1641 | child->redirects=NULL; |
1642 | } |
1643 | free(pi->progs); /* children are an array, they get freed all at once */ |
1644 | pi->progs=NULL; |
1645 | return ret_code; |
1646 | } |
1647 | |
1648 | static int free_pipe_list(struct pipe *head, int indent) |
1649 | { |
1650 | int rcode=0; /* if list has no members */ |
1651 | struct pipe *pi, *next; |
1652 | for (pi=head; pi; pi=next) { |
1653 | final_printf("%s pipe reserved mode %d\n", indenter(indent), pi->r_mode); |
1654 | rcode = free_pipe(pi, indent); |
1655 | final_printf("%s pipe followup code %d\n", indenter(indent), pi->followup); |
1656 | next=pi->next; |
1657 | pi->next=NULL; |
1658 | free(pi); |
1659 | } |
1660 | return rcode; |
1661 | } |
1662 | |
1663 | /* Select which version we will use */ |
1664 | static int run_list(struct pipe *pi) |
1665 | { |
1666 | int rcode=0; |
1667 | if (fake_mode==0) { |
1668 | rcode = run_list_real(pi); |
1669 | } |
1670 | /* free_pipe_list has the side effect of clearing memory |
1671 | * In the long run that function can be merged with run_list_real, |
1672 | * but doing that now would hobble the debugging effort. */ |
1673 | free_pipe_list(pi,0); |
1674 | return rcode; |
1675 | } |
1676 | |
1677 | /* The API for glob is arguably broken. This routine pushes a non-matching |
1678 | * string into the output structure, removing non-backslashed backslashes. |
1679 | * If someone can prove me wrong, by performing this function within the |
1680 | * original glob(3) api, feel free to rewrite this routine into oblivion. |
1681 | * Return code (0 vs. GLOB_NOSPACE) matches glob(3). |
1682 | * XXX broken if the last character is '\\', check that before calling. |
1683 | */ |
1684 | static int globhack(const char *src, int flags, glob_t *pglob) |
1685 | { |
1686 | int cnt=0, pathc; |
1687 | const char *s; |
1688 | char *dest; |
1689 | for (cnt=1, s=src; s && *s; s++) { |
1690 | if (*s == '\\') s++; |
1691 | cnt++; |
1692 | } |
1693 | dest = malloc(cnt); |
1694 | if (!dest) return GLOB_NOSPACE; |
1695 | if (!(flags & GLOB_APPEND)) { |
1696 | pglob->gl_pathv=NULL; |
1697 | pglob->gl_pathc=0; |
1698 | pglob->gl_offs=0; |
1699 | pglob->gl_offs=0; |
1700 | } |
1701 | pathc = ++pglob->gl_pathc; |
1702 | pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv)); |
1703 | if (pglob->gl_pathv == NULL) return GLOB_NOSPACE; |
1704 | pglob->gl_pathv[pathc-1]=dest; |
1705 | pglob->gl_pathv[pathc]=NULL; |
1706 | for (s=src; s && *s; s++, dest++) { |
1707 | if (*s == '\\') s++; |
1708 | *dest = *s; |
1709 | } |
1710 | *dest='\0'; |
1711 | return 0; |
1712 | } |
1713 | |
1714 | /* XXX broken if the last character is '\\', check that before calling */ |
1715 | static int glob_needed(const char *s) |
1716 | { |
1717 | for (; *s; s++) { |
1718 | if (*s == '\\') s++; |
1719 | if (strchr("*[?",*s)) return 1; |
1720 | } |
1721 | return 0; |
1722 | } |
1723 | |
1724 | static int xglob(o_string *dest, int flags, glob_t *pglob) |
1725 | { |
1726 | int gr; |
1727 | |
1728 | /* short-circuit for null word */ |
1729 | /* we can code this better when the debug_printf's are gone */ |
1730 | if (dest->length == 0) { |
1731 | if (dest->nonnull) { |
1732 | /* bash man page calls this an "explicit" null */ |
1733 | gr = globhack(dest->data, flags, pglob); |
1734 | debug_printf("globhack returned %d\n",gr); |
1735 | } else { |
1736 | return 0; |
1737 | } |
1738 | } else if (glob_needed(dest->data)) { |
1739 | gr = glob(dest->data, flags, NULL, pglob); |
1740 | debug_printf("glob returned %d\n",gr); |
1741 | if (gr == GLOB_NOMATCH) { |
1742 | /* quote removal, or more accurately, backslash removal */ |
1743 | gr = globhack(dest->data, flags, pglob); |
1744 | debug_printf("globhack returned %d\n",gr); |
1745 | } |
1746 | } else { |
1747 | gr = globhack(dest->data, flags, pglob); |
1748 | debug_printf("globhack returned %d\n",gr); |
1749 | } |
1750 | if (gr == GLOB_NOSPACE) |
1751 | bb_error_msg_and_die("out of memory during glob"); |
1752 | if (gr != 0) { /* GLOB_ABORTED ? */ |
1753 | bb_error_msg("glob(3) error %d",gr); |
1754 | } |
1755 | /* globprint(glob_target); */ |
1756 | return gr; |
1757 | } |
1758 | |
1759 | /* This is used to get/check local shell variables */ |
1760 | static char *get_local_var(const char *s) |
1761 | { |
1762 | struct variables *cur; |
1763 | |
1764 | if (!s) |
1765 | return NULL; |
1766 | for (cur = top_vars; cur; cur=cur->next) |
1767 | if(strcmp(cur->name, s)==0) |
1768 | return cur->value; |
1769 | return NULL; |
1770 | } |
1771 | |
1772 | /* This is used to set local shell variables |
1773 | flg_export==0 if only local (not exporting) variable |
1774 | flg_export==1 if "new" exporting environ |
1775 | flg_export>1 if current startup environ (not call putenv()) */ |
1776 | static int set_local_var(const char *s, int flg_export) |
1777 | { |
1778 | char *name, *value; |
1779 | int result=0; |
1780 | struct variables *cur; |
1781 | |
1782 | name=strdup(s); |
1783 | |
1784 | /* Assume when we enter this function that we are already in |
1785 | * NAME=VALUE format. So the first order of business is to |
1786 | * split 's' on the '=' into 'name' and 'value' */ |
1787 | value = strchr(name, '='); |
1788 | if (value==0 && ++value==0) { |
1789 | free(name); |
1790 | return -1; |
1791 | } |
1792 | *value++ = 0; |
1793 | |
1794 | for(cur = top_vars; cur; cur = cur->next) { |
1795 | if(strcmp(cur->name, name)==0) |
1796 | break; |
1797 | } |
1798 | |
1799 | if(cur) { |
1800 | if(strcmp(cur->value, value)==0) { |
1801 | if(flg_export>0 && cur->flg_export==0) |
1802 | cur->flg_export=flg_export; |
1803 | else |
1804 | result++; |
1805 | } else { |
1806 | if(cur->flg_read_only) { |
1807 | bb_error_msg("%s: readonly variable", name); |
1808 | result = -1; |
1809 | } else { |
1810 | if(flg_export>0 || cur->flg_export>1) |
1811 | cur->flg_export=1; |
1812 | free(cur->value); |
1813 | |
1814 | cur->value = strdup(value); |
1815 | } |
1816 | } |
1817 | } else { |
1818 | cur = malloc(sizeof(struct variables)); |
1819 | if(!cur) { |
1820 | result = -1; |
1821 | } else { |
1822 | cur->name = strdup(name); |
1823 | if(cur->name == 0) { |
1824 | free(cur); |
1825 | result = -1; |
1826 | } else { |
1827 | struct variables *bottom = top_vars; |
1828 | cur->value = strdup(value); |
1829 | cur->next = 0; |
1830 | cur->flg_export = flg_export; |
1831 | cur->flg_read_only = 0; |
1832 | while(bottom->next) bottom=bottom->next; |
1833 | bottom->next = cur; |
1834 | } |
1835 | } |
1836 | } |
1837 | |
1838 | if(result==0 && cur->flg_export==1) { |
1839 | *(value-1) = '='; |
1840 | result = putenv(name); |
1841 | } else { |
1842 | free(name); |
1843 | if(result>0) /* equivalent to previous set */ |
1844 | result = 0; |
1845 | } |
1846 | return result; |
1847 | } |
1848 | |
1849 | static void unset_local_var(const char *name) |
1850 | { |
1851 | struct variables *cur; |
1852 | |
1853 | if (name) { |
1854 | for (cur = top_vars; cur; cur=cur->next) { |
1855 | if(strcmp(cur->name, name)==0) |
1856 | break; |
1857 | } |
1858 | if(cur!=0) { |
1859 | struct variables *next = top_vars; |
1860 | if(cur->flg_read_only) { |
1861 | bb_error_msg("%s: readonly variable", name); |
1862 | return; |
1863 | } else { |
1864 | if(cur->flg_export) |
1865 | unsetenv(cur->name); |
1866 | free(cur->name); |
1867 | free(cur->value); |
1868 | while (next->next != cur) |
1869 | next = next->next; |
1870 | next->next = cur->next; |
1871 | } |
1872 | free(cur); |
1873 | } |
1874 | } |
1875 | } |
1876 | |
1877 | static int is_assignment(const char *s) |
1878 | { |
1879 | if (s==NULL || !isalpha(*s)) return 0; |
1880 | ++s; |
1881 | while(isalnum(*s) || *s=='_') ++s; |
1882 | return *s=='='; |
1883 | } |
1884 | |
1885 | /* the src parameter allows us to peek forward to a possible &n syntax |
1886 | * for file descriptor duplication, e.g., "2>&1". |
1887 | * Return code is 0 normally, 1 if a syntax error is detected in src. |
1888 | * Resource errors (in xmalloc) cause the process to exit */ |
1889 | static int setup_redirect(struct p_context *ctx, int fd, redir_type style, |
1890 | struct in_str *input) |
1891 | { |
1892 | struct child_prog *child=ctx->child; |
1893 | struct redir_struct *redir = child->redirects; |
1894 | struct redir_struct *last_redir=NULL; |
1895 | |
1896 | /* Create a new redir_struct and drop it onto the end of the linked list */ |
1897 | while(redir) { |
1898 | last_redir=redir; |
1899 | redir=redir->next; |
1900 | } |
1901 | redir = xmalloc(sizeof(struct redir_struct)); |
1902 | redir->next=NULL; |
1903 | redir->word.gl_pathv=NULL; |
1904 | if (last_redir) { |
1905 | last_redir->next=redir; |
1906 | } else { |
1907 | child->redirects=redir; |
1908 | } |
1909 | |
1910 | redir->type=style; |
1911 | redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ; |
1912 | |
1913 | debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip); |
1914 | |
1915 | /* Check for a '2>&1' type redirect */ |
1916 | redir->dup = redirect_dup_num(input); |
1917 | if (redir->dup == -2) return 1; /* syntax error */ |
1918 | if (redir->dup != -1) { |
1919 | /* Erik had a check here that the file descriptor in question |
1920 | * is legit; I postpone that to "run time" |
1921 | * A "-" representation of "close me" shows up as a -3 here */ |
1922 | debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup); |
1923 | } else { |
1924 | /* We do _not_ try to open the file that src points to, |
1925 | * since we need to return and let src be expanded first. |
1926 | * Set ctx->pending_redirect, so we know what to do at the |
1927 | * end of the next parsed word. |
1928 | */ |
1929 | ctx->pending_redirect = redir; |
1930 | } |
1931 | return 0; |
1932 | } |
1933 | |
1934 | static struct pipe *new_pipe(void) { |
1935 | struct pipe *pi; |
1936 | pi = xmalloc(sizeof(struct pipe)); |
1937 | pi->num_progs = 0; |
1938 | pi->progs = NULL; |
1939 | pi->next = NULL; |
1940 | pi->followup = 0; /* invalid */ |
1941 | pi->r_mode = RES_NONE; |
1942 | return pi; |
1943 | } |
1944 | |
1945 | static void initialize_context(struct p_context *ctx) |
1946 | { |
1947 | ctx->pipe=NULL; |
1948 | ctx->pending_redirect=NULL; |
1949 | ctx->child=NULL; |
1950 | ctx->list_head=new_pipe(); |
1951 | ctx->pipe=ctx->list_head; |
1952 | ctx->w=RES_NONE; |
1953 | ctx->stack=NULL; |
1954 | ctx->old_flag=0; |
1955 | done_command(ctx); /* creates the memory for working child */ |
1956 | } |
1957 | |
1958 | /* normal return is 0 |
1959 | * if a reserved word is found, and processed, return 1 |
1960 | * should handle if, then, elif, else, fi, for, while, until, do, done. |
1961 | * case, function, and select are obnoxious, save those for later. |
1962 | */ |
1963 | static int reserved_word(o_string *dest, struct p_context *ctx) |
1964 | { |
1965 | struct reserved_combo { |
1966 | char *literal; |
1967 | int code; |
1968 | long flag; |
1969 | }; |
1970 | /* Mostly a list of accepted follow-up reserved words. |
1971 | * FLAG_END means we are done with the sequence, and are ready |
1972 | * to turn the compound list into a command. |
1973 | * FLAG_START means the word must start a new compound list. |
1974 | */ |
1975 | static struct reserved_combo reserved_list[] = { |
1976 | { "if", RES_IF, FLAG_THEN | FLAG_START }, |
1977 | { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI }, |
1978 | { "elif", RES_ELIF, FLAG_THEN }, |
1979 | { "else", RES_ELSE, FLAG_FI }, |
1980 | { "fi", RES_FI, FLAG_END }, |
1981 | { "for", RES_FOR, FLAG_IN | FLAG_START }, |
1982 | { "while", RES_WHILE, FLAG_DO | FLAG_START }, |
1983 | { "until", RES_UNTIL, FLAG_DO | FLAG_START }, |
1984 | { "in", RES_IN, FLAG_DO }, |
1985 | { "do", RES_DO, FLAG_DONE }, |
1986 | { "done", RES_DONE, FLAG_END } |
1987 | }; |
1988 | struct reserved_combo *r; |
1989 | for (r=reserved_list; |
1990 | #define NRES sizeof(reserved_list)/sizeof(struct reserved_combo) |
1991 | r<reserved_list+NRES; r++) { |
1992 | if (strcmp(dest->data, r->literal) == 0) { |
1993 | debug_printf("found reserved word %s, code %d\n",r->literal,r->code); |
1994 | if (r->flag & FLAG_START) { |
1995 | struct p_context *new = xmalloc(sizeof(struct p_context)); |
1996 | debug_printf("push stack\n"); |
1997 | if (ctx->w == RES_IN || ctx->w == RES_FOR) { |
1998 | syntax(); |
1999 | free(new); |
2000 | ctx->w = RES_SNTX; |
2001 | b_reset(dest); |
2002 | return 1; |
2003 | } |
2004 | *new = *ctx; /* physical copy */ |
2005 | initialize_context(ctx); |
2006 | ctx->stack=new; |
2007 | } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) { |
2008 | syntax(); |
2009 | ctx->w = RES_SNTX; |
2010 | b_reset(dest); |
2011 | return 1; |
2012 | } |
2013 | ctx->w=r->code; |
2014 | ctx->old_flag = r->flag; |
2015 | if (ctx->old_flag & FLAG_END) { |
2016 | struct p_context *old; |
2017 | debug_printf("pop stack\n"); |
2018 | done_pipe(ctx,PIPE_SEQ); |
2019 | old = ctx->stack; |
2020 | old->child->group = ctx->list_head; |
2021 | old->child->subshell = 0; |
2022 | *ctx = *old; /* physical copy */ |
2023 | free(old); |
2024 | } |
2025 | b_reset (dest); |
2026 | return 1; |
2027 | } |
2028 | } |
2029 | return 0; |
2030 | } |
2031 | |
2032 | /* normal return is 0. |
2033 | * Syntax or xglob errors return 1. */ |
2034 | static int done_word(o_string *dest, struct p_context *ctx) |
2035 | { |
2036 | struct child_prog *child=ctx->child; |
2037 | glob_t *glob_target; |
2038 | int gr, flags = 0; |
2039 | |
2040 | debug_printf("done_word: %s %p\n", dest->data, child); |
2041 | if (dest->length == 0 && !dest->nonnull) { |
2042 | debug_printf(" true null, ignored\n"); |
2043 | return 0; |
2044 | } |
2045 | if (ctx->pending_redirect) { |
2046 | glob_target = &ctx->pending_redirect->word; |
2047 | } else { |
2048 | if (child->group) { |
2049 | syntax(); |
2050 | return 1; /* syntax error, groups and arglists don't mix */ |
2051 | } |
2052 | if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) { |
2053 | debug_printf("checking %s for reserved-ness\n",dest->data); |
2054 | if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX; |
2055 | } |
2056 | glob_target = &child->glob_result; |
2057 | if (child->argv) flags |= GLOB_APPEND; |
2058 | } |
2059 | gr = xglob(dest, flags, glob_target); |
2060 | if (gr != 0) return 1; |
2061 | |
2062 | b_reset(dest); |
2063 | if (ctx->pending_redirect) { |
2064 | ctx->pending_redirect=NULL; |
2065 | if (glob_target->gl_pathc != 1) { |
2066 | bb_error_msg("ambiguous redirect"); |
2067 | return 1; |
2068 | } |
2069 | } else { |
2070 | child->argv = glob_target->gl_pathv; |
2071 | } |
2072 | if (ctx->w == RES_FOR) { |
2073 | done_word(dest,ctx); |
2074 | done_pipe(ctx,PIPE_SEQ); |
2075 | } |
2076 | return 0; |
2077 | } |
2078 | |
2079 | /* The only possible error here is out of memory, in which case |
2080 | * xmalloc exits. */ |
2081 | static int done_command(struct p_context *ctx) |
2082 | { |
2083 | /* The child is really already in the pipe structure, so |
2084 | * advance the pipe counter and make a new, null child. |
2085 | * Only real trickiness here is that the uncommitted |
2086 | * child structure, to which ctx->child points, is not |
2087 | * counted in pi->num_progs. */ |
2088 | struct pipe *pi=ctx->pipe; |
2089 | struct child_prog *prog=ctx->child; |
2090 | |
2091 | if (prog && prog->group == NULL |
2092 | && prog->argv == NULL |
2093 | && prog->redirects == NULL) { |
2094 | debug_printf("done_command: skipping null command\n"); |
2095 | return 0; |
2096 | } else if (prog) { |
2097 | pi->num_progs++; |
2098 | debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs); |
2099 | } else { |
2100 | debug_printf("done_command: initializing\n"); |
2101 | } |
2102 | pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1)); |
2103 | |
2104 | prog = pi->progs + pi->num_progs; |
2105 | prog->redirects = NULL; |
2106 | prog->argv = NULL; |
2107 | prog->is_stopped = 0; |
2108 | prog->group = NULL; |
2109 | prog->glob_result.gl_pathv = NULL; |
2110 | prog->family = pi; |
2111 | prog->sp = 0; |
2112 | ctx->child = prog; |
2113 | prog->type = ctx->type; |
2114 | |
2115 | /* but ctx->pipe and ctx->list_head remain unchanged */ |
2116 | return 0; |
2117 | } |
2118 | |
2119 | static int done_pipe(struct p_context *ctx, pipe_style type) |
2120 | { |
2121 | struct pipe *new_p; |
2122 | done_command(ctx); /* implicit closure of previous command */ |
2123 | debug_printf("done_pipe, type %d\n", type); |
2124 | ctx->pipe->followup = type; |
2125 | ctx->pipe->r_mode = ctx->w; |
2126 | new_p=new_pipe(); |
2127 | ctx->pipe->next = new_p; |
2128 | ctx->pipe = new_p; |
2129 | ctx->child = NULL; |
2130 | done_command(ctx); /* set up new pipe to accept commands */ |
2131 | return 0; |
2132 | } |
2133 | |
2134 | /* peek ahead in the in_str to find out if we have a "&n" construct, |
2135 | * as in "2>&1", that represents duplicating a file descriptor. |
2136 | * returns either -2 (syntax error), -1 (no &), or the number found. |
2137 | */ |
2138 | static int redirect_dup_num(struct in_str *input) |
2139 | { |
2140 | int ch, d=0, ok=0; |
2141 | ch = b_peek(input); |
2142 | if (ch != '&') return -1; |
2143 | |
2144 | b_getch(input); /* get the & */ |
2145 | ch=b_peek(input); |
2146 | if (ch == '-') { |
2147 | b_getch(input); |
2148 | return -3; /* "-" represents "close me" */ |
2149 | } |
2150 | while (isdigit(ch)) { |
2151 | d = d*10+(ch-'0'); |
2152 | ok=1; |
2153 | b_getch(input); |
2154 | ch = b_peek(input); |
2155 | } |
2156 | if (ok) return d; |
2157 | |
2158 | bb_error_msg("ambiguous redirect"); |
2159 | return -2; |
2160 | } |
2161 | |
2162 | /* If a redirect is immediately preceded by a number, that number is |
2163 | * supposed to tell which file descriptor to redirect. This routine |
2164 | * looks for such preceding numbers. In an ideal world this routine |
2165 | * needs to handle all the following classes of redirects... |
2166 | * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo |
2167 | * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo |
2168 | * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo |
2169 | * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo |
2170 | * A -1 output from this program means no valid number was found, so the |
2171 | * caller should use the appropriate default for this redirection. |
2172 | */ |
2173 | static int redirect_opt_num(o_string *o) |
2174 | { |
2175 | int num; |
2176 | |
2177 | if (o->length==0) return -1; |
2178 | for(num=0; num<o->length; num++) { |
2179 | if (!isdigit(*(o->data+num))) { |
2180 | return -1; |
2181 | } |
2182 | } |
2183 | /* reuse num (and save an int) */ |
2184 | num=atoi(o->data); |
2185 | b_reset(o); |
2186 | return num; |
2187 | } |
2188 | |
2189 | static FILE *generate_stream_from_list(struct pipe *head) |
2190 | { |
2191 | FILE *pf; |
2192 | int pid, channel[2]; |
2193 | if (pipe(channel)<0) bb_perror_msg_and_die("pipe"); |
2194 | #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__) |
2195 | pid=fork(); |
2196 | #else |
2197 | pid=vfork(); |
2198 | #endif |
2199 | if (pid<0) { |
2200 | bb_perror_msg_and_die("fork"); |
2201 | } else if (pid==0) { |
2202 | close(channel[0]); |
2203 | if (channel[1] != 1) { |
2204 | dup2(channel[1],1); |
2205 | close(channel[1]); |
2206 | } |
2207 | _exit(run_list_real(head)); /* leaks memory */ |
2208 | } |
2209 | debug_printf("forked child %d\n",pid); |
2210 | close(channel[1]); |
2211 | pf = fdopen(channel[0],"r"); |
2212 | debug_printf("pipe on FILE *%p\n",pf); |
2213 | return pf; |
2214 | } |
2215 | |
2216 | /* this version hacked for testing purposes */ |
2217 | /* return code is exit status of the process that is run. */ |
2218 | static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end) |
2219 | { |
2220 | int retcode; |
2221 | o_string result=NULL_O_STRING; |
2222 | struct p_context inner; |
2223 | FILE *p; |
2224 | struct in_str pipe_str; |
2225 | initialize_context(&inner); |
2226 | |
2227 | /* recursion to generate command */ |
2228 | retcode = parse_stream(&result, &inner, input, subst_end); |
2229 | if (retcode != 0) return retcode; /* syntax error or EOF */ |
2230 | done_word(&result, &inner); |
2231 | done_pipe(&inner, PIPE_SEQ); |
2232 | b_free(&result); |
2233 | |
2234 | p=generate_stream_from_list(inner.list_head); |
2235 | if (p==NULL) return 1; |
2236 | mark_open(fileno(p)); |
2237 | setup_file_in_str(&pipe_str, p); |
2238 | |
2239 | /* now send results of command back into original context */ |
2240 | retcode = parse_stream(dest, ctx, &pipe_str, '\0'); |
2241 | /* XXX In case of a syntax error, should we try to kill the child? |
2242 | * That would be tough to do right, so just read until EOF. */ |
2243 | if (retcode == 1) { |
2244 | while (b_getch(&pipe_str)!=EOF) { /* discard */ }; |
2245 | } |
2246 | |
2247 | debug_printf("done reading from pipe, pclose()ing\n"); |
2248 | /* This is the step that wait()s for the child. Should be pretty |
2249 | * safe, since we just read an EOF from its stdout. We could try |
2250 | * to better, by using wait(), and keeping track of background jobs |
2251 | * at the same time. That would be a lot of work, and contrary |
2252 | * to the KISS philosophy of this program. */ |
2253 | mark_closed(fileno(p)); |
2254 | retcode=pclose(p); |
2255 | free_pipe_list(inner.list_head,0); |
2256 | debug_printf("pclosed, retcode=%d\n",retcode); |
2257 | /* XXX this process fails to trim a single trailing newline */ |
2258 | return retcode; |
2259 | } |
2260 | |
2261 | static int parse_group(o_string *dest, struct p_context *ctx, |
2262 | struct in_str *input, int ch) |
2263 | { |
2264 | int rcode, endch=0; |
2265 | struct p_context sub; |
2266 | struct child_prog *child = ctx->child; |
2267 | if (child->argv) { |
2268 | syntax(); |
2269 | return 1; /* syntax error, groups and arglists don't mix */ |
2270 | } |
2271 | initialize_context(&sub); |
2272 | switch (ch) { |
2273 | case '(': endch=')'; child->subshell=1; break; |
2274 | case '{': endch='}'; break; |
2275 | default: syntax(); /* really logic error */ |
2276 | } |
2277 | rcode=parse_stream(dest,&sub,input,endch); |
2278 | done_word(dest,&sub); /* finish off the final word in the subcontext */ |
2279 | done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */ |
2280 | child->group = sub.list_head; |
2281 | return rcode; |
2282 | /* child remains "open", available for possible redirects */ |
2283 | } |
2284 | |
2285 | /* basically useful version until someone wants to get fancier, |
2286 | * see the bash man page under "Parameter Expansion" */ |
2287 | static char *lookup_param(char *src) |
2288 | { |
2289 | char *p=NULL; |
2290 | if (src) { |
2291 | p = getenv(src); |
2292 | if (!p) |
2293 | p = get_local_var(src); |
2294 | } |
2295 | return p; |
2296 | } |
2297 | |
2298 | /* return code: 0 for OK, 1 for syntax error */ |
2299 | static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input) |
2300 | { |
2301 | int i, advance=0; |
2302 | char sep[]=" "; |
2303 | int ch = input->peek(input); /* first character after the $ */ |
2304 | debug_printf("handle_dollar: ch=%c\n",ch); |
2305 | if (isalpha(ch)) { |
2306 | b_addchr(dest, SPECIAL_VAR_SYMBOL); |
2307 | ctx->child->sp++; |
2308 | while(ch=b_peek(input),isalnum(ch) || ch=='_') { |
2309 | b_getch(input); |
2310 | b_addchr(dest,ch); |
2311 | } |
2312 | b_addchr(dest, SPECIAL_VAR_SYMBOL); |
2313 | } else if (isdigit(ch)) { |
2314 | i = ch-'0'; /* XXX is $0 special? */ |
2315 | if (i<global_argc) { |
2316 | parse_string(dest, ctx, global_argv[i]); /* recursion */ |
2317 | } |
2318 | advance = 1; |
2319 | } else switch (ch) { |
2320 | case '$': |
2321 | b_adduint(dest,getpid()); |
2322 | advance = 1; |
2323 | break; |
2324 | case '!': |
2325 | if (last_bg_pid > 0) b_adduint(dest, last_bg_pid); |
2326 | advance = 1; |
2327 | break; |
2328 | case '?': |
2329 | b_adduint(dest,last_return_code); |
2330 | advance = 1; |
2331 | break; |
2332 | case '#': |
2333 | b_adduint(dest,global_argc ? global_argc-1 : 0); |
2334 | advance = 1; |
2335 | break; |
2336 | case '{': |
2337 | b_addchr(dest, SPECIAL_VAR_SYMBOL); |
2338 | ctx->child->sp++; |
2339 | b_getch(input); |
2340 | /* XXX maybe someone will try to escape the '}' */ |
2341 | while(ch=b_getch(input),ch!=EOF && ch!='}') { |
2342 | b_addchr(dest,ch); |
2343 | } |
2344 | if (ch != '}') { |
2345 | syntax(); |
2346 | return 1; |
2347 | } |
2348 | b_addchr(dest, SPECIAL_VAR_SYMBOL); |
2349 | break; |
2350 | case '(': |
2351 | b_getch(input); |
2352 | process_command_subs(dest, ctx, input, ')'); |
2353 | break; |
2354 | case '*': |
2355 | sep[0]=ifs[0]; |
2356 | for (i=1; i<global_argc; i++) { |
2357 | parse_string(dest, ctx, global_argv[i]); |
2358 | if (i+1 < global_argc) parse_string(dest, ctx, sep); |
2359 | } |
2360 | break; |
2361 | case '@': |
2362 | case '-': |
2363 | case '_': |
2364 | /* still unhandled, but should be eventually */ |
2365 | bb_error_msg("unhandled syntax: $%c",ch); |
2366 | return 1; |
2367 | break; |
2368 | default: |
2369 | b_addqchr(dest,'$',dest->quote); |
2370 | } |
2371 | /* Eat the character if the flag was set. If the compiler |
2372 | * is smart enough, we could substitute "b_getch(input);" |
2373 | * for all the "advance = 1;" above, and also end up with |
2374 | * a nice size-optimized program. Hah! That'll be the day. |
2375 | */ |
2376 | if (advance) b_getch(input); |
2377 | return 0; |
2378 | } |
2379 | |
2380 | int parse_string(o_string *dest, struct p_context *ctx, const char *src) |
2381 | { |
2382 | struct in_str foo; |
2383 | setup_string_in_str(&foo, src); |
2384 | return parse_stream(dest, ctx, &foo, '\0'); |
2385 | } |
2386 | |
2387 | /* return code is 0 for normal exit, 1 for syntax error */ |
2388 | int parse_stream(o_string *dest, struct p_context *ctx, |
2389 | struct in_str *input, int end_trigger) |
2390 | { |
2391 | int ch, m; |
2392 | int redir_fd; |
2393 | redir_type redir_style; |
2394 | int next; |
2395 | |
2396 | /* Only double-quote state is handled in the state variable dest->quote. |
2397 | * A single-quote triggers a bypass of the main loop until its mate is |
2398 | * found. When recursing, quote state is passed in via dest->quote. */ |
2399 | |
2400 | debug_printf("parse_stream, end_trigger=%d\n",end_trigger); |
2401 | while ((ch=b_getch(input))!=EOF) { |
2402 | m = map[ch]; |
2403 | next = (ch == '\n') ? 0 : b_peek(input); |
2404 | debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n", |
2405 | ch,ch,m,dest->quote); |
2406 | if (m==0 || ((m==1 || m==2) && dest->quote)) { |
2407 | b_addqchr(dest, ch, dest->quote); |
2408 | } else { |
2409 | if (m==2) { /* unquoted IFS */ |
2410 | if (done_word(dest, ctx)) { |
2411 | return 1; |
2412 | } |
2413 | /* If we aren't performing a substitution, treat a newline as a |
2414 | * command separator. */ |
2415 | if (end_trigger != '\0' && ch=='\n') |
2416 | done_pipe(ctx,PIPE_SEQ); |
2417 | } |
2418 | if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) { |
2419 | debug_printf("leaving parse_stream (triggered)\n"); |
2420 | return 0; |
2421 | } |
2422 | if (m!=2) switch (ch) { |
2423 | case '#': |
2424 | if (dest->length == 0 && !dest->quote) { |
2425 | while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); } |
2426 | } else { |
2427 | b_addqchr(dest, ch, dest->quote); |
2428 | } |
2429 | break; |
2430 | case '\\': |
2431 | if (next == EOF) { |
2432 | syntax(); |
2433 | return 1; |
2434 | } |
2435 | b_addqchr(dest, '\\', dest->quote); |
2436 | b_addqchr(dest, b_getch(input), dest->quote); |
2437 | break; |
2438 | case '$': |
2439 | if (handle_dollar(dest, ctx, input)!=0) return 1; |
2440 | break; |
2441 | case '\'': |
2442 | dest->nonnull = 1; |
2443 | while(ch=b_getch(input),ch!=EOF && ch!='\'') { |
2444 | b_addchr(dest,ch); |
2445 | } |
2446 | if (ch==EOF) { |
2447 | syntax(); |
2448 | return 1; |
2449 | } |
2450 | break; |
2451 | case '"': |
2452 | dest->nonnull = 1; |
2453 | dest->quote = !dest->quote; |
2454 | break; |
2455 | case '`': |
2456 | process_command_subs(dest, ctx, input, '`'); |
2457 | break; |
2458 | case '>': |
2459 | redir_fd = redirect_opt_num(dest); |
2460 | done_word(dest, ctx); |
2461 | redir_style=REDIRECT_OVERWRITE; |
2462 | if (next == '>') { |
2463 | redir_style=REDIRECT_APPEND; |
2464 | b_getch(input); |
2465 | } else if (next == '(') { |
2466 | syntax(); /* until we support >(list) Process Substitution */ |
2467 | return 1; |
2468 | } |
2469 | setup_redirect(ctx, redir_fd, redir_style, input); |
2470 | break; |
2471 | case '<': |
2472 | redir_fd = redirect_opt_num(dest); |
2473 | done_word(dest, ctx); |
2474 | redir_style=REDIRECT_INPUT; |
2475 | if (next == '<') { |
2476 | redir_style=REDIRECT_HEREIS; |
2477 | b_getch(input); |
2478 | } else if (next == '>') { |
2479 | redir_style=REDIRECT_IO; |
2480 | b_getch(input); |
2481 | } else if (next == '(') { |
2482 | syntax(); /* until we support <(list) Process Substitution */ |
2483 | return 1; |
2484 | } |
2485 | setup_redirect(ctx, redir_fd, redir_style, input); |
2486 | break; |
2487 | case ';': |
2488 | done_word(dest, ctx); |
2489 | done_pipe(ctx,PIPE_SEQ); |
2490 | break; |
2491 | case '&': |
2492 | done_word(dest, ctx); |
2493 | if (next=='&') { |
2494 | b_getch(input); |
2495 | done_pipe(ctx,PIPE_AND); |
2496 | } else { |
2497 | done_pipe(ctx,PIPE_BG); |
2498 | } |
2499 | break; |
2500 | case '|': |
2501 | done_word(dest, ctx); |
2502 | if (next=='|') { |
2503 | b_getch(input); |
2504 | done_pipe(ctx,PIPE_OR); |
2505 | } else { |
2506 | /* we could pick up a file descriptor choice here |
2507 | * with redirect_opt_num(), but bash doesn't do it. |
2508 | * "echo foo 2| cat" yields "foo 2". */ |
2509 | done_command(ctx); |
2510 | } |
2511 | break; |
2512 | case '(': |
2513 | case '{': |
2514 | if (parse_group(dest, ctx, input, ch)!=0) return 1; |
2515 | break; |
2516 | case ')': |
2517 | case '}': |
2518 | syntax(); /* Proper use of this character caught by end_trigger */ |
2519 | return 1; |
2520 | break; |
2521 | default: |
2522 | syntax(); /* this is really an internal logic error */ |
2523 | return 1; |
2524 | } |
2525 | } |
2526 | } |
2527 | /* complain if quote? No, maybe we just finished a command substitution |
2528 | * that was quoted. Example: |
2529 | * $ echo "`cat foo` plus more" |
2530 | * and we just got the EOF generated by the subshell that ran "cat foo" |
2531 | * The only real complaint is if we got an EOF when end_trigger != '\0', |
2532 | * that is, we were really supposed to get end_trigger, and never got |
2533 | * one before the EOF. Can't use the standard "syntax error" return code, |
2534 | * so that parse_stream_outer can distinguish the EOF and exit smoothly. */ |
2535 | debug_printf("leaving parse_stream (EOF)\n"); |
2536 | if (end_trigger != '\0') return -1; |
2537 | return 0; |
2538 | } |
2539 | |
2540 | static void mapset(const char *set, int code) |
2541 | { |
2542 | const unsigned char *s; |
2543 | for (s = (const unsigned char *)set; *s; s++) map[(int)*s] = code; |
2544 | } |
2545 | |
2546 | static void update_ifs_map(void) |
2547 | { |
2548 | /* char *ifs and char map[256] are both globals. */ |
2549 | ifs = getenv("IFS"); |
2550 | if (ifs == NULL) ifs=" \t\n"; |
2551 | /* Precompute a list of 'flow through' behavior so it can be treated |
2552 | * quickly up front. Computation is necessary because of IFS. |
2553 | * Special case handling of IFS == " \t\n" is not implemented. |
2554 | * The map[] array only really needs two bits each, and on most machines |
2555 | * that would be faster because of the reduced L1 cache footprint. |
2556 | */ |
2557 | memset(map,0,sizeof(map)); /* most characters flow through always */ |
2558 | mapset("\\$'\"`", 3); /* never flow through */ |
2559 | mapset("<>;&|(){}#", 1); /* flow through if quoted */ |
2560 | mapset(ifs, 2); /* also flow through if quoted */ |
2561 | } |
2562 | |
2563 | /* most recursion does not come through here, the exception is |
2564 | * from builtin_source() */ |
2565 | int parse_stream_outer(struct in_str *inp, int flag) |
2566 | { |
2567 | |
2568 | struct p_context ctx; |
2569 | o_string temp=NULL_O_STRING; |
2570 | int rcode; |
2571 | do { |
2572 | ctx.type = flag; |
2573 | initialize_context(&ctx); |
2574 | update_ifs_map(); |
2575 | if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0); |
2576 | inp->promptmode=1; |
2577 | rcode = parse_stream(&temp, &ctx, inp, '\n'); |
2578 | if (rcode != 1 && ctx.old_flag != 0) { |
2579 | syntax(); |
2580 | } |
2581 | if (rcode != 1 && ctx.old_flag == 0) { |
2582 | done_word(&temp, &ctx); |
2583 | done_pipe(&ctx,PIPE_SEQ); |
2584 | run_list(ctx.list_head); |
2585 | } else { |
2586 | if (ctx.old_flag != 0) { |
2587 | free(ctx.stack); |
2588 | b_reset(&temp); |
2589 | } |
2590 | temp.nonnull = 0; |
2591 | temp.quote = 0; |
2592 | inp->p = NULL; |
2593 | free_pipe_list(ctx.list_head,0); |
2594 | } |
2595 | b_free(&temp); |
2596 | } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */ |
2597 | return 0; |
2598 | } |
2599 | |
2600 | static int parse_string_outer(const char *s, int flag) |
2601 | { |
2602 | struct in_str input; |
2603 | setup_string_in_str(&input, s); |
2604 | return parse_stream_outer(&input, flag); |
2605 | } |
2606 | |
2607 | static int parse_file_outer(FILE *f) |
2608 | { |
2609 | int rcode; |
2610 | struct in_str input; |
2611 | setup_file_in_str(&input, f); |
2612 | rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON); |
2613 | return rcode; |
2614 | } |
2615 | |
2616 | /* Make sure we have a controlling tty. If we get started under a job |
2617 | * aware app (like bash for example), make sure we are now in charge so |
2618 | * we don't fight over who gets the foreground */ |
2619 | static void setup_job_control(void) |
2620 | { |
2621 | static pid_t shell_pgrp; |
2622 | /* Loop until we are in the foreground. */ |
2623 | while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ())) |
2624 | kill (- shell_pgrp, SIGTTIN); |
2625 | |
2626 | /* Ignore interactive and job-control signals. */ |
2627 | signal(SIGINT, SIG_IGN); |
2628 | signal(SIGQUIT, SIG_IGN); |
2629 | signal(SIGTERM, SIG_IGN); |
2630 | signal(SIGTSTP, SIG_IGN); |
2631 | signal(SIGTTIN, SIG_IGN); |
2632 | signal(SIGTTOU, SIG_IGN); |
2633 | signal(SIGCHLD, SIG_IGN); |
2634 | |
2635 | /* Put ourselves in our own process group. */ |
2636 | setsid(); |
2637 | shell_pgrp = getpid(); |
2638 | setpgid(shell_pgrp, shell_pgrp); |
2639 | |
2640 | /* Grab control of the terminal. */ |
2641 | tcsetpgrp(shell_terminal, shell_pgrp); |
2642 | } |
2643 | |
2644 | int hush_main(int argc, char **argv) |
2645 | { |
2646 | int opt; |
2647 | FILE *input; |
2648 | char **e = environ; |
2649 | |
2650 | /* XXX what should these be while sourcing /etc/profile? */ |
2651 | global_argc = argc; |
2652 | global_argv = argv; |
2653 | |
2654 | /* (re?) initialize globals. Sometimes hush_main() ends up calling |
2655 | * hush_main(), therefore we cannot rely on the BSS to zero out this |
2656 | * stuff. Reset these to 0 every time. */ |
2657 | ifs = NULL; |
2658 | /* map[] is taken care of with call to update_ifs_map() */ |
2659 | fake_mode = 0; |
2660 | interactive = 0; |
2661 | close_me_head = NULL; |
2662 | last_bg_pid = 0; |
2663 | job_list = NULL; |
2664 | last_jobid = 0; |
2665 | |
2666 | /* Initialize some more globals to non-zero values */ |
2667 | set_cwd(); |
2668 | if (ENABLE_FEATURE_COMMAND_EDITING) cmdedit_set_initial_prompt(); |
2669 | else PS1 = NULL; |
2670 | PS2 = "> "; |
2671 | |
2672 | /* initialize our shell local variables with the values |
2673 | * currently living in the environment */ |
2674 | if (e) { |
2675 | for (; *e; e++) |
2676 | set_local_var(*e, 2); /* without call putenv() */ |
2677 | } |
2678 | |
2679 | last_return_code=EXIT_SUCCESS; |
2680 | |
2681 | |
2682 | if (argv[0] && argv[0][0] == '-') { |
2683 | debug_printf("\nsourcing /etc/profile\n"); |
2684 | if ((input = fopen("/etc/profile", "r")) != NULL) { |
2685 | mark_open(fileno(input)); |
2686 | parse_file_outer(input); |
2687 | mark_closed(fileno(input)); |
2688 | fclose(input); |
2689 | } |
2690 | } |
2691 | input=stdin; |
2692 | |
2693 | while ((opt = getopt(argc, argv, "c:xif")) > 0) { |
2694 | switch (opt) { |
2695 | case 'c': |
2696 | { |
2697 | global_argv = argv+optind; |
2698 | global_argc = argc-optind; |
2699 | opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON); |
2700 | goto final_return; |
2701 | } |
2702 | break; |
2703 | case 'i': |
2704 | interactive++; |
2705 | break; |
2706 | case 'f': |
2707 | fake_mode++; |
2708 | break; |
2709 | default: |
2710 | #ifndef BB_VER |
2711 | fprintf(stderr, "Usage: sh [FILE]...\n" |
2712 | " or: sh -c command [args]...\n\n"); |
2713 | exit(EXIT_FAILURE); |
2714 | #else |
2715 | bb_show_usage(); |
2716 | #endif |
2717 | } |
2718 | } |
2719 | /* A shell is interactive if the `-i' flag was given, or if all of |
2720 | * the following conditions are met: |
2721 | * no -c command |
2722 | * no arguments remaining or the -s flag given |
2723 | * standard input is a terminal |
2724 | * standard output is a terminal |
2725 | * Refer to Posix.2, the description of the `sh' utility. */ |
2726 | if (argv[optind]==NULL && input==stdin && |
2727 | isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) { |
2728 | interactive++; |
2729 | } |
2730 | |
2731 | debug_printf("\ninteractive=%d\n", interactive); |
2732 | if (interactive) { |
2733 | /* Looks like they want an interactive shell */ |
2734 | #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET |
2735 | printf( "\n\n%s hush - the humble shell v0.01 (testing)\n", |
2736 | BB_BANNER); |
2737 | printf( "Enter 'help' for a list of built-in commands.\n\n"); |
2738 | #endif |
2739 | setup_job_control(); |
2740 | } |
2741 | |
2742 | if (argv[optind]==NULL) { |
2743 | opt=parse_file_outer(stdin); |
2744 | goto final_return; |
2745 | } |
2746 | |
2747 | debug_printf("\nrunning script '%s'\n", argv[optind]); |
2748 | global_argv = argv+optind; |
2749 | global_argc = argc-optind; |
2750 | input = xfopen(argv[optind], "r"); |
2751 | opt = parse_file_outer(input); |
2752 | |
2753 | #ifdef CONFIG_FEATURE_CLEAN_UP |
2754 | fclose(input); |
2755 | if (cwd && cwd != bb_msg_unknown) |
2756 | free((char*)cwd); |
2757 | { |
2758 | struct variables *cur, *tmp; |
2759 | for(cur = top_vars; cur; cur = tmp) { |
2760 | tmp = cur->next; |
2761 | if (!cur->flg_read_only) { |
2762 | free(cur->name); |
2763 | free(cur->value); |
2764 | free(cur); |
2765 | } |
2766 | } |
2767 | } |
2768 | #endif |
2769 | |
2770 | final_return: |
2771 | return opt ? opt : last_return_code; |
2772 | } |
2773 | |
2774 | static char *insert_var_value(char *inp) |
2775 | { |
2776 | int res_str_len = 0; |
2777 | int len; |
2778 | int done = 0; |
2779 | char *p, *p1, *res_str = NULL; |
2780 | |
2781 | while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) { |
2782 | if (p != inp) { |
2783 | len = p - inp; |
2784 | res_str = xrealloc(res_str, (res_str_len + len)); |
2785 | strncpy((res_str + res_str_len), inp, len); |
2786 | res_str_len += len; |
2787 | } |
2788 | inp = ++p; |
2789 | p = strchr(inp, SPECIAL_VAR_SYMBOL); |
2790 | *p = '\0'; |
2791 | if ((p1 = lookup_param(inp))) { |
2792 | len = res_str_len + strlen(p1); |
2793 | res_str = xrealloc(res_str, (1 + len)); |
2794 | strcpy((res_str + res_str_len), p1); |
2795 | res_str_len = len; |
2796 | } |
2797 | *p = SPECIAL_VAR_SYMBOL; |
2798 | inp = ++p; |
2799 | done = 1; |
2800 | } |
2801 | if (done) { |
2802 | res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp))); |
2803 | strcpy((res_str + res_str_len), inp); |
2804 | while ((p = strchr(res_str, '\n'))) { |
2805 | *p = ' '; |
2806 | } |
2807 | } |
2808 | return (res_str == NULL) ? inp : res_str; |
2809 | } |
2810 | |
2811 | static char **make_list_in(char **inp, char *name) |
2812 | { |
2813 | int len, i; |
2814 | int name_len = strlen(name); |
2815 | int n = 0; |
2816 | char **list; |
2817 | char *p1, *p2, *p3; |
2818 | |
2819 | /* create list of variable values */ |
2820 | list = xmalloc(sizeof(*list)); |
2821 | for (i = 0; inp[i]; i++) { |
2822 | p3 = insert_var_value(inp[i]); |
2823 | p1 = p3; |
2824 | while (*p1) { |
2825 | if ((*p1 == ' ')) { |
2826 | p1++; |
2827 | continue; |
2828 | } |
2829 | if ((p2 = strchr(p1, ' '))) { |
2830 | len = p2 - p1; |
2831 | } else { |
2832 | len = strlen(p1); |
2833 | p2 = p1 + len; |
2834 | } |
2835 | /* we use n + 2 in realloc for list,because we add |
2836 | * new element and then we will add NULL element */ |
2837 | list = xrealloc(list, sizeof(*list) * (n + 2)); |
2838 | list[n] = xmalloc(2 + name_len + len); |
2839 | strcpy(list[n], name); |
2840 | strcat(list[n], "="); |
2841 | strncat(list[n], p1, len); |
2842 | list[n++][name_len + len + 1] = '\0'; |
2843 | p1 = p2; |
2844 | } |
2845 | if (p3 != inp[i]) free(p3); |
2846 | } |
2847 | list[n] = NULL; |
2848 | return list; |
2849 | } |
2850 | |
2851 | /* Make new string for parser */ |
2852 | static char * make_string(char ** inp) |
2853 | { |
2854 | char *p; |
2855 | char *str = NULL; |
2856 | int n; |
2857 | int len = 2; |
2858 | |
2859 | for (n = 0; inp[n]; n++) { |
2860 | p = insert_var_value(inp[n]); |
2861 | str = xrealloc(str, (len + strlen(p))); |
2862 | if (n) { |
2863 | strcat(str, " "); |
2864 | } else { |
2865 | *str = '\0'; |
2866 | } |
2867 | strcat(str, p); |
2868 | len = strlen(str) + 3; |
2869 | if (p != inp[n]) free(p); |
2870 | } |
2871 | len = strlen(str); |
2872 | *(str + len) = '\n'; |
2873 | *(str + len + 1) = '\0'; |
2874 | return str; |
2875 | } |