1 /*-
2 * Copyright (c) 2003-2007 Tim Kientzle
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "archive_platform.h"
27 __FBSDID("$FreeBSD: head/lib/libarchive/archive_string.c 201095 2009-12-28 02:33:22Z kientzle $");
28
29 /*
30 * Basic resizable string support, to simplify manipulating arbitrary-sized
31 * strings while minimizing heap activity.
32 */
33
34 #ifdef HAVE_STDLIB_H
35 #include <stdlib.h>
36 #endif
37 #ifdef HAVE_STRING_H
38 #include <string.h>
39 #endif
40 #ifdef HAVE_WCHAR_H
41 #include <wchar.h>
42 #endif
43 #if defined(_WIN32) && !defined(__CYGWIN__)
44 #include <windows.h>
45 #endif
46
47 #include "archive_private.h"
48 #include "archive_string.h"
49
50 struct archive_string *
__archive_string_append(struct archive_string * as,const char * p,size_t s)51 __archive_string_append(struct archive_string *as, const char *p, size_t s)
52 {
53 if (__archive_string_ensure(as, as->length + s + 1) == NULL)
54 __archive_errx(1, "Out of memory");
55 memcpy(as->s + as->length, p, s);
56 as->s[as->length + s] = 0;
57 as->length += s;
58 return (as);
59 }
60
61 void
__archive_string_copy(struct archive_string * dest,struct archive_string * src)62 __archive_string_copy(struct archive_string *dest, struct archive_string *src)
63 {
64 if (src->length == 0)
65 dest->length = 0;
66 else {
67 if (__archive_string_ensure(dest, src->length + 1) == NULL)
68 __archive_errx(1, "Out of memory");
69 memcpy(dest->s, src->s, src->length);
70 dest->length = src->length;
71 dest->s[dest->length] = 0;
72 }
73 }
74
75 void
__archive_string_concat(struct archive_string * dest,struct archive_string * src)76 __archive_string_concat(struct archive_string *dest, struct archive_string *src)
77 {
78 if (src->length > 0) {
79 if (__archive_string_ensure(dest, dest->length + src->length + 1) == NULL)
80 __archive_errx(1, "Out of memory");
81 memcpy(dest->s + dest->length, src->s, src->length);
82 dest->length += src->length;
83 dest->s[dest->length] = 0;
84 }
85 }
86
87 void
__archive_string_free(struct archive_string * as)88 __archive_string_free(struct archive_string *as)
89 {
90 as->length = 0;
91 as->buffer_length = 0;
92 if (as->s != NULL) {
93 free(as->s);
94 as->s = NULL;
95 }
96 }
97
98 /* Returns NULL on any allocation failure. */
99 struct archive_string *
__archive_string_ensure(struct archive_string * as,size_t s)100 __archive_string_ensure(struct archive_string *as, size_t s)
101 {
102 /* If buffer is already big enough, don't reallocate. */
103 if (as->s && (s <= as->buffer_length))
104 return (as);
105
106 /*
107 * Growing the buffer at least exponentially ensures that
108 * append operations are always linear in the number of
109 * characters appended. Using a smaller growth rate for
110 * larger buffers reduces memory waste somewhat at the cost of
111 * a larger constant factor.
112 */
113 if (as->buffer_length < 32)
114 /* Start with a minimum 32-character buffer. */
115 as->buffer_length = 32;
116 else if (as->buffer_length < 8192)
117 /* Buffers under 8k are doubled for speed. */
118 as->buffer_length += as->buffer_length;
119 else {
120 /* Buffers 8k and over grow by at least 25% each time. */
121 size_t old_length = as->buffer_length;
122 as->buffer_length += as->buffer_length / 4;
123 /* Be safe: If size wraps, release buffer and return NULL. */
124 if (as->buffer_length < old_length) {
125 free(as->s);
126 as->s = NULL;
127 return (NULL);
128 }
129 }
130 /*
131 * The computation above is a lower limit to how much we'll
132 * grow the buffer. In any case, we have to grow it enough to
133 * hold the request.
134 */
135 if (as->buffer_length < s)
136 as->buffer_length = s;
137 /* Now we can reallocate the buffer. */
138 as->s = (char *)realloc(as->s, as->buffer_length);
139 if (as->s == NULL)
140 return (NULL);
141 return (as);
142 }
143
144 struct archive_string *
__archive_strncat(struct archive_string * as,const void * _p,size_t n)145 __archive_strncat(struct archive_string *as, const void *_p, size_t n)
146 {
147 size_t s;
148 const char *p, *pp;
149
150 p = (const char *)_p;
151
152 /* Like strlen(p), except won't examine positions beyond p[n]. */
153 s = 0;
154 pp = p;
155 while (*pp && s < n) {
156 pp++;
157 s++;
158 }
159 return (__archive_string_append(as, p, s));
160 }
161
162 struct archive_string *
__archive_strappend_char(struct archive_string * as,char c)163 __archive_strappend_char(struct archive_string *as, char c)
164 {
165 return (__archive_string_append(as, &c, 1));
166 }
167
168 /*
169 * Translates a wide character string into UTF-8 and appends
170 * to the archive_string. Note: returns NULL if conversion fails,
171 * but still leaves a best-effort conversion in the argument as.
172 */
173 struct archive_string *
__archive_strappend_w_utf8(struct archive_string * as,const wchar_t * w)174 __archive_strappend_w_utf8(struct archive_string *as, const wchar_t *w)
175 {
176 char *p;
177 unsigned wc;
178 char buff[256];
179 struct archive_string *return_val = as;
180
181 /*
182 * Convert one wide char at a time into 'buff', whenever that
183 * fills, append it to the string.
184 */
185 p = buff;
186 while (*w != L'\0') {
187 /* Flush the buffer when we have <=16 bytes free. */
188 /* (No encoding has a single character >16 bytes.) */
189 if ((size_t)(p - buff) >= (size_t)(sizeof(buff) - 16)) {
190 *p = '\0';
191 archive_strcat(as, buff);
192 p = buff;
193 }
194 wc = *w++;
195 /* If this is a surrogate pair, assemble the full code point.*/
196 /* Note: wc must not be wchar_t here, because the full code
197 * point can be more than 16 bits! */
198 if (wc >= 0xD800 && wc <= 0xDBff
199 && *w >= 0xDC00 && *w <= 0xDFFF) {
200 wc -= 0xD800;
201 wc *= 0x400;
202 wc += (*w - 0xDC00);
203 wc += 0x10000;
204 ++w;
205 }
206 /* Translate code point to UTF8 */
207 if (wc <= 0x7f) {
208 *p++ = (char)wc;
209 } else if (wc <= 0x7ff) {
210 *p++ = 0xc0 | ((wc >> 6) & 0x1f);
211 *p++ = 0x80 | (wc & 0x3f);
212 } else if (wc <= 0xffff) {
213 *p++ = 0xe0 | ((wc >> 12) & 0x0f);
214 *p++ = 0x80 | ((wc >> 6) & 0x3f);
215 *p++ = 0x80 | (wc & 0x3f);
216 } else if (wc <= 0x1fffff) {
217 *p++ = 0xf0 | ((wc >> 18) & 0x07);
218 *p++ = 0x80 | ((wc >> 12) & 0x3f);
219 *p++ = 0x80 | ((wc >> 6) & 0x3f);
220 *p++ = 0x80 | (wc & 0x3f);
221 } else {
222 /* Unicode has no codes larger than 0x1fffff. */
223 /* TODO: use \uXXXX escape here instead of ? */
224 *p++ = '?';
225 return_val = NULL;
226 }
227 }
228 *p = '\0';
229 archive_strcat(as, buff);
230 return (return_val);
231 }
232
233 static int
utf8_to_unicode(int * pwc,const char * s,size_t n)234 utf8_to_unicode(int *pwc, const char *s, size_t n)
235 {
236 int ch;
237
238 /*
239 * Decode 1-4 bytes depending on the value of the first byte.
240 */
241 ch = (unsigned char)*s;
242 if (ch == 0) {
243 return (0); /* Standard: return 0 for end-of-string. */
244 }
245 if ((ch & 0x80) == 0) {
246 *pwc = ch & 0x7f;
247 return (1);
248 }
249 if ((ch & 0xe0) == 0xc0) {
250 if (n < 2)
251 return (-1);
252 if ((s[1] & 0xc0) != 0x80) return (-1);
253 *pwc = ((ch & 0x1f) << 6) | (s[1] & 0x3f);
254 return (2);
255 }
256 if ((ch & 0xf0) == 0xe0) {
257 if (n < 3)
258 return (-1);
259 if ((s[1] & 0xc0) != 0x80) return (-1);
260 if ((s[2] & 0xc0) != 0x80) return (-1);
261 *pwc = ((ch & 0x0f) << 12)
262 | ((s[1] & 0x3f) << 6)
263 | (s[2] & 0x3f);
264 return (3);
265 }
266 if ((ch & 0xf8) == 0xf0) {
267 if (n < 4)
268 return (-1);
269 if ((s[1] & 0xc0) != 0x80) return (-1);
270 if ((s[2] & 0xc0) != 0x80) return (-1);
271 if ((s[3] & 0xc0) != 0x80) return (-1);
272 *pwc = ((ch & 0x07) << 18)
273 | ((s[1] & 0x3f) << 12)
274 | ((s[2] & 0x3f) << 6)
275 | (s[3] & 0x3f);
276 return (4);
277 }
278 /* Invalid first byte. */
279 return (-1);
280 }
281
282 /*
283 * Return a wide-character Unicode string by converting this archive_string
284 * from UTF-8. We assume that systems with 16-bit wchar_t always use
285 * UTF16 and systems with 32-bit wchar_t can accept UCS4.
286 */
287 wchar_t *
__archive_string_utf8_w(struct archive_string * as)288 __archive_string_utf8_w(struct archive_string *as)
289 {
290 wchar_t *ws, *dest;
291 int wc, wc2;/* Must be large enough for a 21-bit Unicode code point. */
292 const char *src;
293 int n;
294
295 ws = (wchar_t *)malloc((as->length + 1) * sizeof(wchar_t));
296 if (ws == NULL)
297 __archive_errx(1, "Out of memory");
298 dest = ws;
299 src = as->s;
300 while (*src != '\0') {
301 n = utf8_to_unicode(&wc, src, 8);
302 if (n == 0)
303 break;
304 if (n < 0) {
305 free(ws);
306 return (NULL);
307 }
308 src += n;
309 if (wc >= 0xDC00 && wc <= 0xDBFF) {
310 /* This is a leading surrogate; some idiot
311 * has translated UTF16 to UTF8 without combining
312 * surrogates; rebuild the full code point before
313 * continuing. */
314 n = utf8_to_unicode(&wc2, src, 8);
315 if (n < 0) {
316 free(ws);
317 return (NULL);
318 }
319 if (n == 0) /* Ignore the leading surrogate */
320 break;
321 if (wc2 < 0xDC00 || wc2 > 0xDFFF) {
322 /* If the second character isn't a
323 * trailing surrogate, then someone
324 * has really screwed up and this is
325 * invalid. */
326 free(ws);
327 return (NULL);
328 } else {
329 src += n;
330 wc -= 0xD800;
331 wc *= 0x400;
332 wc += wc2 - 0xDC00;
333 wc += 0x10000;
334 }
335 }
336 if ((sizeof(wchar_t) < 4) && (wc > 0xffff)) {
337 /* We have a code point that won't fit into a
338 * wchar_t; convert it to a surrogate pair. */
339 wc -= 0x10000;
340 *dest++ = ((wc >> 10) & 0x3ff) + 0xD800;
341 *dest++ = (wc & 0x3ff) + 0xDC00;
342 } else
343 *dest++ = wc;
344 }
345 *dest = L'\0';
346 return (ws);
347 }
348
349 #if defined(_WIN32) && !defined(__CYGWIN__)
350
351 /*
352 * Translates a wide character string into current locale character set
353 * and appends to the archive_string. Note: returns NULL if conversion
354 * fails.
355 *
356 * Win32 builds use WideCharToMultiByte from the Windows API.
357 * (Maybe Cygwin should too? WideCharToMultiByte will know a
358 * lot more about local character encodings than the wcrtomb()
359 * wrapper is going to know.)
360 */
361 struct archive_string *
__archive_strappend_w_mbs(struct archive_string * as,const wchar_t * w)362 __archive_strappend_w_mbs(struct archive_string *as, const wchar_t *w)
363 {
364 char *p;
365 int l, wl;
366 BOOL useDefaultChar = FALSE;
367
368 wl = (int)wcslen(w);
369 l = wl * 4 + 4;
370 p = malloc(l);
371 if (p == NULL)
372 __archive_errx(1, "Out of memory");
373 /* To check a useDefaultChar is to simulate error handling of
374 * the my_wcstombs() which is running on non Windows system with
375 * wctomb().
376 * And to set NULL for last argument is necessary when a codepage
377 * is not CP_ACP(current locale).
378 */
379 l = WideCharToMultiByte(CP_ACP, 0, w, wl, p, l, NULL, &useDefaultChar);
380 if (l == 0) {
381 free(p);
382 return (NULL);
383 }
384 __archive_string_append(as, p, l);
385 free(p);
386 return (as);
387 }
388
389 #else
390
391 /*
392 * Translates a wide character string into current locale character set
393 * and appends to the archive_string. Note: returns NULL if conversion
394 * fails.
395 *
396 * Non-Windows uses ISO C wcrtomb() or wctomb() to perform the conversion
397 * one character at a time. If a non-Windows platform doesn't have
398 * either of these, fall back to the built-in UTF8 conversion.
399 */
400 struct archive_string *
__archive_strappend_w_mbs(struct archive_string * as,const wchar_t * w)401 __archive_strappend_w_mbs(struct archive_string *as, const wchar_t *w)
402 {
403 #if !defined(HAVE_WCTOMB) && !defined(HAVE_WCRTOMB)
404 /* If there's no built-in locale support, fall back to UTF8 always. */
405 return __archive_strappend_w_utf8(as, w);
406 #else
407 /* We cannot use the standard wcstombs() here because it
408 * cannot tell us how big the output buffer should be. So
409 * I've built a loop around wcrtomb() or wctomb() that
410 * converts a character at a time and resizes the string as
411 * needed. We prefer wcrtomb() when it's available because
412 * it's thread-safe. */
413 int n;
414 char *p;
415 char buff[256];
416 #if HAVE_WCRTOMB
417 mbstate_t shift_state;
418
419 memset(&shift_state, 0, sizeof(shift_state));
420 #else
421 /* Clear the shift state before starting. */
422 wctomb(NULL, L'\0');
423 #endif
424
425 /*
426 * Convert one wide char at a time into 'buff', whenever that
427 * fills, append it to the string.
428 */
429 p = buff;
430 while (*w != L'\0') {
431 /* Flush the buffer when we have <=16 bytes free. */
432 /* (No encoding has a single character >16 bytes.) */
433 if ((size_t)(p - buff) >= (size_t)(sizeof(buff) - MB_CUR_MAX)) {
434 *p = '\0';
435 archive_strcat(as, buff);
436 p = buff;
437 }
438 #if HAVE_WCRTOMB
439 n = wcrtomb(p, *w++, &shift_state);
440 #else
441 n = wctomb(p, *w++);
442 #endif
443 if (n == -1)
444 return (NULL);
445 p += n;
446 }
447 *p = '\0';
448 archive_strcat(as, buff);
449 return (as);
450 #endif
451 }
452
453 #endif /* _WIN32 && ! __CYGWIN__ */
454