1 /* quotearg.c - quote arguments for output
2
3 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004, 2005, 2006 Free
4 Software Foundation, Inc.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10
11 This program 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
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
19
20 /* Written by Paul Eggert <eggert@twinsun.com> */
21
22 #ifdef HAVE_CONFIG_H
23 # include <config.h>
24 #endif
25
26 #include "quotearg.h"
27
28 #include "xalloc.h"
29
30 #include <ctype.h>
31 #include <errno.h>
32 #include <limits.h>
33 #include <stdbool.h>
34 #include <stdlib.h>
35 #include <string.h>
36
37 #include "gettext.h"
38 #define _(msgid) gettext (msgid)
39 #define N_(msgid) msgid
40
41 #if HAVE_WCHAR_H
42
43 /* BSD/OS 4.1 wchar.h requires FILE and struct tm to be declared. */
44 # include <stdio.h>
45 # include <time.h>
46
47 # include <wchar.h>
48 #endif
49
50 #if !HAVE_MBRTOWC
51 /* Disable multibyte processing entirely. Since MB_CUR_MAX is 1, the
52 other macros are defined only for documentation and to satisfy C
53 syntax. */
54 # undef MB_CUR_MAX
55 # define MB_CUR_MAX 1
56 # define mbrtowc(pwc, s, n, ps) ((*(pwc) = *(s)) != 0)
57 # define iswprint(wc) isprint ((unsigned char) (wc))
58 # undef HAVE_MBSINIT
59 #endif
60
61 #if !defined mbsinit && !HAVE_MBSINIT
62 # define mbsinit(ps) 1
63 #endif
64
65 #ifndef iswprint
66 # if HAVE_WCTYPE_H
67 # include <wctype.h>
68 # endif
69 # if !defined iswprint && !HAVE_ISWPRINT
70 # define iswprint(wc) 1
71 # endif
72 #endif
73
74 #ifndef SIZE_MAX
75 # define SIZE_MAX ((size_t) -1)
76 #endif
77
78 #define INT_BITS (sizeof (int) * CHAR_BIT)
79
80 struct quoting_options
81 {
82 /* Basic quoting style. */
83 enum quoting_style style;
84
85 /* Quote the characters indicated by this bit vector even if the
86 quoting style would not normally require them to be quoted. */
87 unsigned int quote_these_too[(UCHAR_MAX / INT_BITS) + 1];
88 };
89
90 /* Names of quoting styles. */
91 char const *const quoting_style_args[] =
92 {
93 "literal",
94 "shell",
95 "shell-always",
96 "c",
97 "escape",
98 "locale",
99 "clocale",
100 0
101 };
102
103 /* Correspondences to quoting style names. */
104 enum quoting_style const quoting_style_vals[] =
105 {
106 literal_quoting_style,
107 shell_quoting_style,
108 shell_always_quoting_style,
109 c_quoting_style,
110 escape_quoting_style,
111 locale_quoting_style,
112 clocale_quoting_style
113 };
114
115 /* The default quoting options. */
116 static struct quoting_options default_quoting_options;
117
118 /* Allocate a new set of quoting options, with contents initially identical
119 to O if O is not null, or to the default if O is null.
120 It is the caller's responsibility to free the result. */
121 struct quoting_options *
clone_quoting_options(struct quoting_options * o)122 clone_quoting_options (struct quoting_options *o)
123 {
124 int e = errno;
125 struct quoting_options *p = xmalloc (sizeof *p);
126 *p = *(o ? o : &default_quoting_options);
127 errno = e;
128 return p;
129 }
130
131 /* Get the value of O's quoting style. If O is null, use the default. */
132 enum quoting_style
get_quoting_style(struct quoting_options * o)133 get_quoting_style (struct quoting_options *o)
134 {
135 return (o ? o : &default_quoting_options)->style;
136 }
137
138 /* In O (or in the default if O is null),
139 set the value of the quoting style to S. */
140 void
set_quoting_style(struct quoting_options * o,enum quoting_style s)141 set_quoting_style (struct quoting_options *o, enum quoting_style s)
142 {
143 (o ? o : &default_quoting_options)->style = s;
144 }
145
146 /* In O (or in the default if O is null),
147 set the value of the quoting options for character C to I.
148 Return the old value. Currently, the only values defined for I are
149 0 (the default) and 1 (which means to quote the character even if
150 it would not otherwise be quoted). */
151 int
set_char_quoting(struct quoting_options * o,char c,int i)152 set_char_quoting (struct quoting_options *o, char c, int i)
153 {
154 unsigned char uc = c;
155 unsigned int *p =
156 (o ? o : &default_quoting_options)->quote_these_too + uc / INT_BITS;
157 int shift = uc % INT_BITS;
158 int r = (*p >> shift) & 1;
159 *p ^= ((i & 1) ^ r) << shift;
160 return r;
161 }
162
163 /* MSGID approximates a quotation mark. Return its translation if it
164 has one; otherwise, return either it or "\"", depending on S. */
165 static char const *
gettext_quote(char const * msgid,enum quoting_style s)166 gettext_quote (char const *msgid, enum quoting_style s)
167 {
168 char const *translation = _(msgid);
169 if (translation == msgid && s == clocale_quoting_style)
170 translation = "\"";
171 return translation;
172 }
173
174 /* Place into buffer BUFFER (of size BUFFERSIZE) a quoted version of
175 argument ARG (of size ARGSIZE), using QUOTING_STYLE and the
176 non-quoting-style part of O to control quoting.
177 Terminate the output with a null character, and return the written
178 size of the output, not counting the terminating null.
179 If BUFFERSIZE is too small to store the output string, return the
180 value that would have been returned had BUFFERSIZE been large enough.
181 If ARGSIZE is SIZE_MAX, use the string length of the argument for ARGSIZE.
182
183 This function acts like quotearg_buffer (BUFFER, BUFFERSIZE, ARG,
184 ARGSIZE, O), except it uses QUOTING_STYLE instead of the quoting
185 style specified by O, and O may not be null. */
186
187 static size_t
quotearg_buffer_restyled(char * buffer,size_t buffersize,char const * arg,size_t argsize,enum quoting_style quoting_style,struct quoting_options const * o)188 quotearg_buffer_restyled (char *buffer, size_t buffersize,
189 char const *arg, size_t argsize,
190 enum quoting_style quoting_style,
191 struct quoting_options const *o)
192 {
193 size_t i;
194 size_t len = 0;
195 char const *quote_string = 0;
196 size_t quote_string_len = 0;
197 bool backslash_escapes = false;
198 bool unibyte_locale = MB_CUR_MAX == 1;
199
200 #define STORE(c) \
201 do \
202 { \
203 if (len < buffersize) \
204 buffer[len] = (c); \
205 len++; \
206 } \
207 while (0)
208
209 switch (quoting_style)
210 {
211 case c_quoting_style:
212 STORE ('"');
213 backslash_escapes = true;
214 quote_string = "\"";
215 quote_string_len = 1;
216 break;
217
218 case escape_quoting_style:
219 backslash_escapes = true;
220 break;
221
222 case locale_quoting_style:
223 case clocale_quoting_style:
224 {
225 /* TRANSLATORS:
226 Get translations for open and closing quotation marks.
227
228 The message catalog should translate "`" to a left
229 quotation mark suitable for the locale, and similarly for
230 "'". If the catalog has no translation,
231 locale_quoting_style quotes `like this', and
232 clocale_quoting_style quotes "like this".
233
234 For example, an American English Unicode locale should
235 translate "`" to U+201C (LEFT DOUBLE QUOTATION MARK), and
236 should translate "'" to U+201D (RIGHT DOUBLE QUOTATION
237 MARK). A British English Unicode locale should instead
238 translate these to U+2018 (LEFT SINGLE QUOTATION MARK) and
239 U+2019 (RIGHT SINGLE QUOTATION MARK), respectively.
240
241 If you don't know what to put here, please see
242 <http://en.wikipedia.org/wiki/Quotation_mark#Glyphs>
243 and use glyphs suitable for your language. */
244
245 char const *left = gettext_quote (N_("`"), quoting_style);
246 char const *right = gettext_quote (N_("'"), quoting_style);
247 for (quote_string = left; *quote_string; quote_string++)
248 STORE (*quote_string);
249 backslash_escapes = true;
250 quote_string = right;
251 quote_string_len = strlen (quote_string);
252 }
253 break;
254
255 case shell_always_quoting_style:
256 STORE ('\'');
257 quote_string = "'";
258 quote_string_len = 1;
259 break;
260
261 default:
262 break;
263 }
264
265 for (i = 0; ! (argsize == SIZE_MAX ? arg[i] == '\0' : i == argsize); i++)
266 {
267 unsigned char c;
268 unsigned char esc;
269
270 if (backslash_escapes
271 && quote_string_len
272 && i + quote_string_len <= argsize
273 && memcmp (arg + i, quote_string, quote_string_len) == 0)
274 STORE ('\\');
275
276 c = arg[i];
277 switch (c)
278 {
279 case '\0':
280 if (backslash_escapes)
281 {
282 STORE ('\\');
283 STORE ('0');
284 STORE ('0');
285 c = '0';
286 }
287 break;
288
289 case '?':
290 switch (quoting_style)
291 {
292 case shell_quoting_style:
293 goto use_shell_always_quoting_style;
294
295 case c_quoting_style:
296 if (i + 2 < argsize && arg[i + 1] == '?')
297 switch (arg[i + 2])
298 {
299 case '!': case '\'':
300 case '(': case ')': case '-': case '/':
301 case '<': case '=': case '>':
302 /* Escape the second '?' in what would otherwise be
303 a trigraph. */
304 c = arg[i + 2];
305 i += 2;
306 STORE ('?');
307 STORE ('\\');
308 STORE ('?');
309 break;
310
311 default:
312 break;
313 }
314 break;
315
316 default:
317 break;
318 }
319 break;
320
321 case '\a': esc = 'a'; goto c_escape;
322 case '\b': esc = 'b'; goto c_escape;
323 case '\f': esc = 'f'; goto c_escape;
324 case '\n': esc = 'n'; goto c_and_shell_escape;
325 case '\r': esc = 'r'; goto c_and_shell_escape;
326 case '\t': esc = 't'; goto c_and_shell_escape;
327 case '\v': esc = 'v'; goto c_escape;
328 case '\\': esc = c; goto c_and_shell_escape;
329
330 c_and_shell_escape:
331 if (quoting_style == shell_quoting_style)
332 goto use_shell_always_quoting_style;
333 c_escape:
334 if (backslash_escapes)
335 {
336 c = esc;
337 goto store_escape;
338 }
339 break;
340
341 case '{': case '}': /* sometimes special if isolated */
342 if (! (argsize == SIZE_MAX ? arg[1] == '\0' : argsize == 1))
343 break;
344 /* Fall through. */
345 case '#': case '~':
346 if (i != 0)
347 break;
348 /* Fall through. */
349 case ' ':
350 case '!': /* special in bash */
351 case '"': case '$': case '&':
352 case '(': case ')': case '*': case ';':
353 case '<':
354 case '=': /* sometimes special in 0th or (with "set -k") later args */
355 case '>': case '[':
356 case '^': /* special in old /bin/sh, e.g. SunOS 4.1.4 */
357 case '`': case '|':
358 /* A shell special character. In theory, '$' and '`' could
359 be the first bytes of multibyte characters, which means
360 we should check them with mbrtowc, but in practice this
361 doesn't happen so it's not worth worrying about. */
362 if (quoting_style == shell_quoting_style)
363 goto use_shell_always_quoting_style;
364 break;
365
366 case '\'':
367 switch (quoting_style)
368 {
369 case shell_quoting_style:
370 goto use_shell_always_quoting_style;
371
372 case shell_always_quoting_style:
373 STORE ('\'');
374 STORE ('\\');
375 STORE ('\'');
376 break;
377
378 default:
379 break;
380 }
381 break;
382
383 case '%': case '+': case ',': case '-': case '.': case '/':
384 case '0': case '1': case '2': case '3': case '4': case '5':
385 case '6': case '7': case '8': case '9': case ':':
386 case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
387 case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
388 case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
389 case 'S': case 'T': case 'U': case 'V': case 'W': case 'X':
390 case 'Y': case 'Z': case ']': case '_': case 'a': case 'b':
391 case 'c': case 'd': case 'e': case 'f': case 'g': case 'h':
392 case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
393 case 'o': case 'p': case 'q': case 'r': case 's': case 't':
394 case 'u': case 'v': case 'w': case 'x': case 'y': case 'z':
395 /* These characters don't cause problems, no matter what the
396 quoting style is. They cannot start multibyte sequences. */
397 break;
398
399 default:
400 /* If we have a multibyte sequence, copy it until we reach
401 its end, find an error, or come back to the initial shift
402 state. For C-like styles, if the sequence has
403 unprintable characters, escape the whole sequence, since
404 we can't easily escape single characters within it. */
405 {
406 /* Length of multibyte sequence found so far. */
407 size_t m;
408
409 bool printable;
410
411 if (unibyte_locale)
412 {
413 m = 1;
414 printable = isprint (c) != 0;
415 }
416 else
417 {
418 mbstate_t mbstate;
419 memset (&mbstate, 0, sizeof mbstate);
420
421 m = 0;
422 printable = true;
423 if (argsize == SIZE_MAX)
424 argsize = strlen (arg);
425
426 do
427 {
428 wchar_t w;
429 size_t bytes = mbrtowc (&w, &arg[i + m],
430 argsize - (i + m), &mbstate);
431 if (bytes == 0)
432 break;
433 else if (bytes == (size_t) -1)
434 {
435 printable = false;
436 break;
437 }
438 else if (bytes == (size_t) -2)
439 {
440 printable = false;
441 while (i + m < argsize && arg[i + m])
442 m++;
443 break;
444 }
445 else
446 {
447 /* Work around a bug with older shells that "see" a '\'
448 that is really the 2nd byte of a multibyte character.
449 In practice the problem is limited to ASCII
450 chars >= '@' that are shell special chars. */
451 if ('[' == 0x5b && quoting_style == shell_quoting_style)
452 {
453 size_t j;
454 for (j = 1; j < bytes; j++)
455 switch (arg[i + m + j])
456 {
457 case '[': case '\\': case '^':
458 case '`': case '|':
459 goto use_shell_always_quoting_style;
460
461 default:
462 break;
463 }
464 }
465
466 if (! iswprint (w))
467 printable = false;
468 m += bytes;
469 }
470 }
471 while (! mbsinit (&mbstate));
472 }
473
474 if (1 < m || (backslash_escapes && ! printable))
475 {
476 /* Output a multibyte sequence, or an escaped
477 unprintable unibyte character. */
478 size_t ilim = i + m;
479
480 for (;;)
481 {
482 if (backslash_escapes && ! printable)
483 {
484 STORE ('\\');
485 STORE ('0' + (c >> 6));
486 STORE ('0' + ((c >> 3) & 7));
487 c = '0' + (c & 7);
488 }
489 if (ilim <= i + 1)
490 break;
491 STORE (c);
492 c = arg[++i];
493 }
494
495 goto store_c;
496 }
497 }
498 }
499
500 if (! (backslash_escapes
501 && o->quote_these_too[c / INT_BITS] & (1 << (c % INT_BITS))))
502 goto store_c;
503
504 store_escape:
505 STORE ('\\');
506
507 store_c:
508 STORE (c);
509 }
510
511 if (i == 0 && quoting_style == shell_quoting_style)
512 goto use_shell_always_quoting_style;
513
514 if (quote_string)
515 for (; *quote_string; quote_string++)
516 STORE (*quote_string);
517
518 if (len < buffersize)
519 buffer[len] = '\0';
520 return len;
521
522 use_shell_always_quoting_style:
523 return quotearg_buffer_restyled (buffer, buffersize, arg, argsize,
524 shell_always_quoting_style, o);
525 }
526
527 /* Place into buffer BUFFER (of size BUFFERSIZE) a quoted version of
528 argument ARG (of size ARGSIZE), using O to control quoting.
529 If O is null, use the default.
530 Terminate the output with a null character, and return the written
531 size of the output, not counting the terminating null.
532 If BUFFERSIZE is too small to store the output string, return the
533 value that would have been returned had BUFFERSIZE been large enough.
534 If ARGSIZE is SIZE_MAX, use the string length of the argument for
535 ARGSIZE. */
536 size_t
quotearg_buffer(char * buffer,size_t buffersize,char const * arg,size_t argsize,struct quoting_options const * o)537 quotearg_buffer (char *buffer, size_t buffersize,
538 char const *arg, size_t argsize,
539 struct quoting_options const *o)
540 {
541 struct quoting_options const *p = o ? o : &default_quoting_options;
542 int e = errno;
543 size_t r = quotearg_buffer_restyled (buffer, buffersize, arg, argsize,
544 p->style, p);
545 errno = e;
546 return r;
547 }
548
549 /* Like quotearg_buffer (..., ARG, ARGSIZE, O), except return newly
550 allocated storage containing the quoted string. */
551 char *
quotearg_alloc(char const * arg,size_t argsize,struct quoting_options const * o)552 quotearg_alloc (char const *arg, size_t argsize,
553 struct quoting_options const *o)
554 {
555 int e = errno;
556 size_t bufsize = quotearg_buffer (0, 0, arg, argsize, o) + 1;
557 char *buf = xmalloc (bufsize);
558 quotearg_buffer (buf, bufsize, arg, argsize, o);
559 errno = e;
560 return buf;
561 }
562
563 /* Use storage slot N to return a quoted version of argument ARG.
564 ARG is of size ARGSIZE, but if that is SIZE_MAX, ARG is a
565 null-terminated string.
566 OPTIONS specifies the quoting options.
567 The returned value points to static storage that can be
568 reused by the next call to this function with the same value of N.
569 N must be nonnegative. N is deliberately declared with type "int"
570 to allow for future extensions (using negative values). */
571 static char *
quotearg_n_options(int n,char const * arg,size_t argsize,struct quoting_options const * options)572 quotearg_n_options (int n, char const *arg, size_t argsize,
573 struct quoting_options const *options)
574 {
575 int e = errno;
576
577 /* Preallocate a slot 0 buffer, so that the caller can always quote
578 one small component of a "memory exhausted" message in slot 0. */
579 static char slot0[256];
580 static unsigned int nslots = 1;
581 unsigned int n0 = n;
582 struct slotvec
583 {
584 size_t size;
585 char *val;
586 };
587 static struct slotvec slotvec0 = {sizeof slot0, slot0};
588 static struct slotvec *slotvec = &slotvec0;
589
590 if (n < 0)
591 abort ();
592
593 if (nslots <= n0)
594 {
595 /* FIXME: technically, the type of n1 should be `unsigned int',
596 but that evokes an unsuppressible warning from gcc-4.0.1 and
597 older. If gcc ever provides an option to suppress that warning,
598 revert to the original type, so that the test in xalloc_oversized
599 is once again performed only at compile time. */
600 size_t n1 = n0 + 1;
601
602 if (xalloc_oversized (n1, sizeof *slotvec))
603 xalloc_die ();
604
605 if (slotvec == &slotvec0)
606 {
607 slotvec = xmalloc (sizeof *slotvec);
608 *slotvec = slotvec0;
609 }
610 slotvec = xrealloc (slotvec, n1 * sizeof *slotvec);
611 memset (slotvec + nslots, 0, (n1 - nslots) * sizeof *slotvec);
612 nslots = n1;
613 }
614
615 {
616 size_t size = slotvec[n].size;
617 char *val = slotvec[n].val;
618 size_t qsize = quotearg_buffer (val, size, arg, argsize, options);
619
620 if (size <= qsize)
621 {
622 slotvec[n].size = size = qsize + 1;
623 if (val != slot0)
624 free (val);
625 slotvec[n].val = val = xmalloc (size);
626 quotearg_buffer (val, size, arg, argsize, options);
627 }
628
629 errno = e;
630 return val;
631 }
632 }
633
634 char *
quotearg_n(int n,char const * arg)635 quotearg_n (int n, char const *arg)
636 {
637 return quotearg_n_options (n, arg, SIZE_MAX, &default_quoting_options);
638 }
639
640 char *
quotearg(char const * arg)641 quotearg (char const *arg)
642 {
643 return quotearg_n (0, arg);
644 }
645
646 /* Return quoting options for STYLE, with no extra quoting. */
647 static struct quoting_options
quoting_options_from_style(enum quoting_style style)648 quoting_options_from_style (enum quoting_style style)
649 {
650 struct quoting_options o;
651 o.style = style;
652 memset (o.quote_these_too, 0, sizeof o.quote_these_too);
653 return o;
654 }
655
656 char *
quotearg_n_style(int n,enum quoting_style s,char const * arg)657 quotearg_n_style (int n, enum quoting_style s, char const *arg)
658 {
659 struct quoting_options const o = quoting_options_from_style (s);
660 return quotearg_n_options (n, arg, SIZE_MAX, &o);
661 }
662
663 char *
quotearg_n_style_mem(int n,enum quoting_style s,char const * arg,size_t argsize)664 quotearg_n_style_mem (int n, enum quoting_style s,
665 char const *arg, size_t argsize)
666 {
667 struct quoting_options const o = quoting_options_from_style (s);
668 return quotearg_n_options (n, arg, argsize, &o);
669 }
670
671 char *
quotearg_style(enum quoting_style s,char const * arg)672 quotearg_style (enum quoting_style s, char const *arg)
673 {
674 return quotearg_n_style (0, s, arg);
675 }
676
677 char *
quotearg_char(char const * arg,char ch)678 quotearg_char (char const *arg, char ch)
679 {
680 struct quoting_options options;
681 options = default_quoting_options;
682 set_char_quoting (&options, ch, 1);
683 return quotearg_n_options (0, arg, SIZE_MAX, &options);
684 }
685
686 char *
quotearg_colon(char const * arg)687 quotearg_colon (char const *arg)
688 {
689 return quotearg_char (arg, ':');
690 }
691