1 | /* Create and destroy argument vectors (argv's) |
2 | Copyright (C) 1992-2025 Free Software Foundation, Inc. |
3 | Written by Fred Fish @ Cygnus Support |
4 | |
5 | This file is part of the libiberty library. |
6 | Libiberty is free software; you can redistribute it and/or |
7 | modify it under the terms of the GNU Library General Public |
8 | License as published by the Free Software Foundation; either |
9 | version 2 of the License, or (at your option) any later version. |
10 | |
11 | Libiberty is distributed in the hope that it will be useful, |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | Library General Public License for more details. |
15 | |
16 | You should have received a copy of the GNU Library General Public |
17 | License along with libiberty; see the file COPYING.LIB. If |
18 | not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, |
19 | Boston, MA 02110-1301, USA. */ |
20 | |
21 | |
22 | /* Create and destroy argument vectors. An argument vector is simply an |
23 | array of string pointers, terminated by a NULL pointer. */ |
24 | |
25 | #ifdef HAVE_CONFIG_H |
26 | #include "config.h" |
27 | #endif |
28 | #include "ansidecl.h" |
29 | #include "libiberty.h" |
30 | #include "safe-ctype.h" |
31 | |
32 | /* Routines imported from standard C runtime libraries. */ |
33 | |
34 | #include <stddef.h> |
35 | #include <string.h> |
36 | #include <stdlib.h> |
37 | #include <stdio.h> |
38 | #include <sys/types.h> |
39 | #ifdef HAVE_UNISTD_H |
40 | #include <unistd.h> |
41 | #endif |
42 | #if HAVE_SYS_STAT_H |
43 | #include <sys/stat.h> |
44 | #endif |
45 | |
46 | #ifndef NULL |
47 | #define NULL 0 |
48 | #endif |
49 | |
50 | #ifndef EOS |
51 | #define EOS '\0' |
52 | #endif |
53 | |
54 | #define INITIAL_MAXARGC 8 /* Number of args + NULL in initial argv */ |
55 | |
56 | |
57 | /* |
58 | |
59 | @deftypefn Extension char** dupargv (char * const *@var{vector}) |
60 | |
61 | Duplicate an argument vector. Simply scans through @var{vector}, |
62 | duplicating each argument until the terminating @code{NULL} is found. |
63 | Returns a pointer to the argument vector if successful. Returns |
64 | @code{NULL} if there is insufficient memory to complete building the |
65 | argument vector. |
66 | |
67 | @end deftypefn |
68 | |
69 | */ |
70 | |
71 | char ** |
72 | dupargv (char * const *argv) |
73 | { |
74 | int argc; |
75 | char **copy; |
76 | |
77 | if (argv == NULL) |
78 | return NULL; |
79 | |
80 | /* the vector */ |
81 | for (argc = 0; argv[argc] != NULL; argc++); |
82 | copy = (char **) xmalloc ((argc + 1) * sizeof (char *)); |
83 | |
84 | /* the strings */ |
85 | for (argc = 0; argv[argc] != NULL; argc++) |
86 | copy[argc] = xstrdup (argv[argc]); |
87 | copy[argc] = NULL; |
88 | return copy; |
89 | } |
90 | |
91 | /* |
92 | |
93 | @deftypefn Extension void freeargv (char **@var{vector}) |
94 | |
95 | Free an argument vector that was built using @code{buildargv}. Simply |
96 | scans through @var{vector}, freeing the memory for each argument until |
97 | the terminating @code{NULL} is found, and then frees @var{vector} |
98 | itself. |
99 | |
100 | @end deftypefn |
101 | |
102 | */ |
103 | |
104 | void freeargv (char **vector) |
105 | { |
106 | register char **scan; |
107 | |
108 | if (vector != NULL) |
109 | { |
110 | for (scan = vector; *scan != NULL; scan++) |
111 | { |
112 | free (ptr: *scan); |
113 | } |
114 | free (ptr: vector); |
115 | } |
116 | } |
117 | |
118 | static void |
119 | consume_whitespace (const char **input) |
120 | { |
121 | while (ISSPACE (**input)) |
122 | { |
123 | (*input)++; |
124 | } |
125 | } |
126 | |
127 | /* |
128 | |
129 | @deftypefn Extension char** buildargv (char *@var{sp}) |
130 | |
131 | Given a pointer to a string, parse the string extracting fields |
132 | separated by whitespace and optionally enclosed within either single |
133 | or double quotes (which are stripped off), and build a vector of |
134 | pointers to copies of the string for each field. The input string |
135 | remains unchanged. The last element of the vector is followed by a |
136 | @code{NULL} element. |
137 | |
138 | All of the memory for the pointer array and copies of the string |
139 | is obtained from @code{xmalloc}. All of the memory can be returned to the |
140 | system with the single function call @code{freeargv}, which takes the |
141 | returned result of @code{buildargv}, as it's argument. |
142 | |
143 | Returns a pointer to the argument vector if successful. Returns |
144 | @code{NULL} if @var{sp} is @code{NULL} or if there is insufficient |
145 | memory to complete building the argument vector. |
146 | |
147 | If the input is a null string (as opposed to a @code{NULL} pointer), |
148 | then buildarg returns an argument vector that has one arg, a null |
149 | string. |
150 | |
151 | @end deftypefn |
152 | |
153 | The memory for the argv array is dynamically expanded as necessary. |
154 | |
155 | In order to provide a working buffer for extracting arguments into, |
156 | with appropriate stripping of quotes and translation of backslash |
157 | sequences, we allocate a working buffer at least as long as the input |
158 | string. This ensures that we always have enough space in which to |
159 | work, since the extracted arg is never larger than the input string. |
160 | |
161 | The argument vector is always kept terminated with a @code{NULL} arg |
162 | pointer, so it can be passed to @code{freeargv} at any time, or |
163 | returned, as appropriate. |
164 | |
165 | */ |
166 | |
167 | char **buildargv (const char *input) |
168 | { |
169 | char *arg; |
170 | char *copybuf; |
171 | int squote = 0; |
172 | int dquote = 0; |
173 | int bsquote = 0; |
174 | int argc = 0; |
175 | int maxargc = 0; |
176 | char **argv = NULL; |
177 | char **nargv; |
178 | |
179 | if (input != NULL) |
180 | { |
181 | copybuf = (char *) xmalloc (strlen (s: input) + 1); |
182 | /* Is a do{}while to always execute the loop once. Always return an |
183 | argv, even for null strings. See NOTES above, test case below. */ |
184 | do |
185 | { |
186 | /* Pick off argv[argc] */ |
187 | consume_whitespace (input: &input); |
188 | |
189 | if ((maxargc == 0) || (argc >= (maxargc - 1))) |
190 | { |
191 | /* argv needs initialization, or expansion */ |
192 | if (argv == NULL) |
193 | { |
194 | maxargc = INITIAL_MAXARGC; |
195 | nargv = (char **) xmalloc (maxargc * sizeof (char *)); |
196 | } |
197 | else |
198 | { |
199 | maxargc *= 2; |
200 | nargv = (char **) xrealloc (argv, maxargc * sizeof (char *)); |
201 | } |
202 | argv = nargv; |
203 | argv[argc] = NULL; |
204 | } |
205 | /* Begin scanning arg */ |
206 | if (*input != EOS) |
207 | { |
208 | arg = copybuf; |
209 | while (*input != EOS) |
210 | { |
211 | if (ISSPACE (*input) && !squote && !dquote && !bsquote) |
212 | { |
213 | break; |
214 | } |
215 | else |
216 | { |
217 | if (bsquote) |
218 | { |
219 | bsquote = 0; |
220 | if (*input != '\n') |
221 | *arg++ = *input; |
222 | } |
223 | else if (*input == '\\' |
224 | && !squote |
225 | && (!dquote |
226 | || strchr (s: "$`\"\\\n" , c: *(input + 1)) != NULL)) |
227 | { |
228 | bsquote = 1; |
229 | } |
230 | else if (squote) |
231 | { |
232 | if (*input == '\'') |
233 | { |
234 | squote = 0; |
235 | } |
236 | else |
237 | { |
238 | *arg++ = *input; |
239 | } |
240 | } |
241 | else if (dquote) |
242 | { |
243 | if (*input == '"') |
244 | { |
245 | dquote = 0; |
246 | } |
247 | else |
248 | { |
249 | *arg++ = *input; |
250 | } |
251 | } |
252 | else |
253 | { |
254 | if (*input == '\'') |
255 | { |
256 | squote = 1; |
257 | } |
258 | else if (*input == '"') |
259 | { |
260 | dquote = 1; |
261 | } |
262 | else |
263 | { |
264 | *arg++ = *input; |
265 | } |
266 | } |
267 | input++; |
268 | } |
269 | } |
270 | *arg = EOS; |
271 | argv[argc] = xstrdup (copybuf); |
272 | argc++; |
273 | } |
274 | argv[argc] = NULL; |
275 | |
276 | consume_whitespace (input: &input); |
277 | } |
278 | while (*input != EOS); |
279 | |
280 | free (ptr: copybuf); |
281 | } |
282 | return (argv); |
283 | } |
284 | |
285 | /* |
286 | |
287 | @deftypefn Extension int writeargv (char * const *@var{argv}, FILE *@var{file}) |
288 | |
289 | Write each member of ARGV, handling all necessary quoting, to the file |
290 | associated with FILE, separated by whitespace. Return 0 on success, |
291 | non-zero if an error occurred while writing to FILE. |
292 | |
293 | @end deftypefn |
294 | |
295 | */ |
296 | |
297 | int |
298 | writeargv (char * const *argv, FILE *f) |
299 | { |
300 | if (f == NULL) |
301 | return 1; |
302 | |
303 | while (*argv != NULL) |
304 | { |
305 | const char *arg = *argv; |
306 | |
307 | while (*arg != EOS) |
308 | { |
309 | char c = *arg; |
310 | |
311 | if (ISSPACE(c) || c == '\\' || c == '\'' || c == '"') |
312 | if (EOF == fputc (c: '\\', stream: f)) |
313 | return 1; |
314 | |
315 | if (EOF == fputc (c: c, stream: f)) |
316 | return 1; |
317 | |
318 | arg++; |
319 | } |
320 | |
321 | /* Write out a pair of quotes for an empty argument. */ |
322 | if (arg == *argv) |
323 | if (EOF == fputs (s: "\"\"" , stream: f)) |
324 | return 1; |
325 | |
326 | if (EOF == fputc (c: '\n', stream: f)) |
327 | return 1; |
328 | |
329 | argv++; |
330 | } |
331 | |
332 | return 0; |
333 | } |
334 | |
335 | /* |
336 | |
337 | @deftypefn Extension void expandargv (int *@var{argcp}, char ***@var{argvp}) |
338 | |
339 | The @var{argcp} and @code{argvp} arguments are pointers to the usual |
340 | @code{argc} and @code{argv} arguments to @code{main}. This function |
341 | looks for arguments that begin with the character @samp{@@}. Any such |
342 | arguments are interpreted as ``response files''. The contents of the |
343 | response file are interpreted as additional command line options. In |
344 | particular, the file is separated into whitespace-separated strings; |
345 | each such string is taken as a command-line option. The new options |
346 | are inserted in place of the option naming the response file, and |
347 | @code{*argcp} and @code{*argvp} will be updated. If the value of |
348 | @code{*argvp} is modified by this function, then the new value has |
349 | been dynamically allocated and can be deallocated by the caller with |
350 | @code{freeargv}. However, most callers will simply call |
351 | @code{expandargv} near the beginning of @code{main} and allow the |
352 | operating system to free the memory when the program exits. |
353 | |
354 | @end deftypefn |
355 | |
356 | */ |
357 | |
358 | void |
359 | expandargv (int *argcp, char ***argvp) |
360 | { |
361 | /* The argument we are currently processing. */ |
362 | int i = 0; |
363 | /* To check if ***argvp has been dynamically allocated. */ |
364 | char ** const original_argv = *argvp; |
365 | /* Limit the number of response files that we parse in order |
366 | to prevent infinite recursion. */ |
367 | unsigned int iteration_limit = 2000; |
368 | /* Loop over the arguments, handling response files. We always skip |
369 | ARGVP[0], as that is the name of the program being run. */ |
370 | while (++i < *argcp) |
371 | { |
372 | /* The name of the response file. */ |
373 | const char *filename; |
374 | /* The response file. */ |
375 | FILE *f; |
376 | /* An upper bound on the number of characters in the response |
377 | file. */ |
378 | long pos; |
379 | /* The number of characters in the response file, when actually |
380 | read. */ |
381 | size_t len; |
382 | /* A dynamically allocated buffer used to hold options read from a |
383 | response file. */ |
384 | char *buffer; |
385 | /* Dynamically allocated storage for the options read from the |
386 | response file. */ |
387 | char **file_argv; |
388 | /* The number of options read from the response file, if any. */ |
389 | size_t file_argc; |
390 | #ifdef S_ISDIR |
391 | struct stat sb; |
392 | #endif |
393 | /* We are only interested in options of the form "@file". */ |
394 | filename = (*argvp)[i]; |
395 | if (filename[0] != '@') |
396 | continue; |
397 | /* If we have iterated too many times then stop. */ |
398 | if (-- iteration_limit == 0) |
399 | { |
400 | fprintf (stderr, format: "%s: error: too many @-files encountered\n" , (*argvp)[0]); |
401 | xexit (status: 1); |
402 | } |
403 | #ifdef S_ISDIR |
404 | if (stat (file: filename+1, buf: &sb) < 0) |
405 | continue; |
406 | if (S_ISDIR(sb.st_mode)) |
407 | { |
408 | fprintf (stderr, format: "%s: error: @-file refers to a directory\n" , (*argvp)[0]); |
409 | xexit (status: 1); |
410 | } |
411 | #endif |
412 | /* Read the contents of the file. */ |
413 | f = fopen (filename: ++filename, modes: "r" ); |
414 | if (!f) |
415 | continue; |
416 | if (fseek (stream: f, off: 0L, SEEK_END) == -1) |
417 | goto error; |
418 | pos = ftell (stream: f); |
419 | if (pos == -1) |
420 | goto error; |
421 | if (fseek (stream: f, off: 0L, SEEK_SET) == -1) |
422 | goto error; |
423 | buffer = (char *) xmalloc (pos * sizeof (char) + 1); |
424 | len = fread (ptr: buffer, size: sizeof (char), n: pos, stream: f); |
425 | if (len != (size_t) pos |
426 | /* On Windows, fread may return a value smaller than POS, |
427 | due to CR/LF->CR translation when reading text files. |
428 | That does not in-and-of itself indicate failure. */ |
429 | && ferror (stream: f)) |
430 | { |
431 | free (ptr: buffer); |
432 | goto error; |
433 | } |
434 | /* Add a NUL terminator. */ |
435 | buffer[len] = '\0'; |
436 | /* Parse the string. */ |
437 | file_argv = buildargv (input: buffer); |
438 | /* If *ARGVP is not already dynamically allocated, copy it. */ |
439 | if (*argvp == original_argv) |
440 | *argvp = dupargv (argv: *argvp); |
441 | /* Count the number of arguments. */ |
442 | file_argc = 0; |
443 | while (file_argv[file_argc]) |
444 | ++file_argc; |
445 | /* Free the original option's memory. */ |
446 | free (ptr: (*argvp)[i]); |
447 | /* Now, insert FILE_ARGV into ARGV. The "+1" below handles the |
448 | NULL terminator at the end of ARGV. */ |
449 | *argvp = ((char **) |
450 | xrealloc (*argvp, |
451 | (*argcp + file_argc + 1) * sizeof (char *))); |
452 | memmove (dest: *argvp + i + file_argc, src: *argvp + i + 1, |
453 | n: (*argcp - i) * sizeof (char *)); |
454 | memcpy (dest: *argvp + i, src: file_argv, n: file_argc * sizeof (char *)); |
455 | /* The original option has been replaced by all the new |
456 | options. */ |
457 | *argcp += file_argc - 1; |
458 | /* Free up memory allocated to process the response file. We do |
459 | not use freeargv because the individual options in FILE_ARGV |
460 | are now in the main ARGV. */ |
461 | free (ptr: file_argv); |
462 | free (ptr: buffer); |
463 | /* Rescan all of the arguments just read to support response |
464 | files that include other response files. */ |
465 | --i; |
466 | error: |
467 | /* We're all done with the file now. */ |
468 | fclose (stream: f); |
469 | } |
470 | } |
471 | |
472 | /* |
473 | |
474 | @deftypefn Extension int countargv (char * const *@var{argv}) |
475 | |
476 | Return the number of elements in @var{argv}. |
477 | Returns zero if @var{argv} is NULL. |
478 | |
479 | @end deftypefn |
480 | |
481 | */ |
482 | |
483 | int |
484 | countargv (char * const *argv) |
485 | { |
486 | int argc; |
487 | |
488 | if (argv == NULL) |
489 | return 0; |
490 | for (argc = 0; argv[argc] != NULL; argc++) |
491 | continue; |
492 | return argc; |
493 | } |
494 | |
495 | #ifdef MAIN |
496 | |
497 | /* Simple little test driver. */ |
498 | |
499 | static const char *const tests[] = |
500 | { |
501 | "a simple command line" , |
502 | "arg 'foo' is single quoted" , |
503 | "arg \"bar\" is double quoted" , |
504 | "arg \"foo bar\" has embedded whitespace" , |
505 | "arg 'Jack said \\'hi\\'' has single quotes" , |
506 | "arg 'Jack said \\\"hi\\\"' has double quotes" , |
507 | "a b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 8 9" , |
508 | |
509 | /* This should be expanded into only one argument. */ |
510 | "trailing-whitespace " , |
511 | |
512 | "" , |
513 | NULL |
514 | }; |
515 | |
516 | int |
517 | main (void) |
518 | { |
519 | char **argv; |
520 | const char *const *test; |
521 | char **targs; |
522 | |
523 | for (test = tests; *test != NULL; test++) |
524 | { |
525 | printf ("buildargv(\"%s\")\n" , *test); |
526 | if ((argv = buildargv (*test)) == NULL) |
527 | { |
528 | printf ("failed!\n\n" ); |
529 | } |
530 | else |
531 | { |
532 | for (targs = argv; *targs != NULL; targs++) |
533 | { |
534 | printf ("\t\"%s\"\n" , *targs); |
535 | } |
536 | printf ("\n" ); |
537 | } |
538 | freeargv (argv); |
539 | } |
540 | |
541 | return 0; |
542 | } |
543 | |
544 | #endif /* MAIN */ |
545 | |