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[fontconfig.git] / src / fccache.c
1 /*
2 * Copyright © 2000 Keith Packard
3 * Copyright © 2005 Patrick Lam
4 *
5 * Permission to use, copy, modify, distribute, and sell this software and its
6 * documentation for any purpose is hereby granted without fee, provided that
7 * the above copyright notice appear in all copies and that both that
8 * copyright notice and this permission notice appear in supporting
9 * documentation, and that the name of Keith Packard not be used in
10 * advertising or publicity pertaining to distribution of the software without
11 * specific, written prior permission. Keith Packard makes no
12 * representations about the suitability of this software for any purpose. It
13 * is provided "as is" without express or implied warranty.
14 *
15 * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
16 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
17 * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
18 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
19 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
20 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
21 * PERFORMANCE OF THIS SOFTWARE.
22 */
23
24 #include "fcint.h"
25 #include "../fc-arch/fcarch.h"
26 #include <stdio.h>
27 #include <fcntl.h>
28 #include <dirent.h>
29 #include <string.h>
30 #include <sys/types.h>
31 #if defined(HAVE_MMAP) || defined(__CYGWIN__)
32 # include <unistd.h>
33 # include <sys/mman.h>
34 #elif defined(_WIN32)
35 # include <windows.h>
36 #endif
37
38 #ifndef O_BINARY
39 #define O_BINARY 0
40 #endif
41
42 struct MD5Context {
43 FcChar32 buf[4];
44 FcChar32 bits[2];
45 unsigned char in[64];
46 };
47
48 static void MD5Init(struct MD5Context *ctx);
49 static void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len);
50 static void MD5Final(unsigned char digest[16], struct MD5Context *ctx);
51 static void MD5Transform(FcChar32 buf[4], FcChar32 in[16]);
52
53 #define CACHEBASE_LEN (1 + 32 + 1 + sizeof (FC_ARCHITECTURE) + sizeof (FC_CACHE_SUFFIX))
54
55 static const char bin2hex[] = { '0', '1', '2', '3',
56 '4', '5', '6', '7',
57 '8', '9', 'a', 'b',
58 'c', 'd', 'e', 'f' };
59
60 static FcChar8 *
61 FcDirCacheBasename (const FcChar8 * dir, FcChar8 cache_base[CACHEBASE_LEN])
62 {
63 unsigned char hash[16];
64 FcChar8 *hex_hash;
65 int cnt;
66 struct MD5Context ctx;
67
68 MD5Init (&ctx);
69 MD5Update (&ctx, (unsigned char *)dir, strlen ((char *) dir));
70
71 MD5Final (hash, &ctx);
72
73 cache_base[0] = '/';
74 hex_hash = cache_base + 1;
75 for (cnt = 0; cnt < 16; ++cnt)
76 {
77 hex_hash[2*cnt ] = bin2hex[hash[cnt] >> 4];
78 hex_hash[2*cnt+1] = bin2hex[hash[cnt] & 0xf];
79 }
80 hex_hash[2*cnt] = 0;
81 strcat ((char *) cache_base, "-" FC_ARCHITECTURE FC_CACHE_SUFFIX);
82
83 return cache_base;
84 }
85
86 FcBool
87 FcDirCacheUnlink (const FcChar8 *dir, FcConfig *config)
88 {
89 FcChar8 *cache_hashed = NULL;
90 FcChar8 cache_base[CACHEBASE_LEN];
91 FcStrList *list;
92 FcChar8 *cache_dir;
93
94 FcDirCacheBasename (dir, cache_base);
95
96 list = FcStrListCreate (config->cacheDirs);
97 if (!list)
98 return FcFalse;
99
100 while ((cache_dir = FcStrListNext (list)))
101 {
102 cache_hashed = FcStrPlus (cache_dir, cache_base);
103 if (!cache_hashed)
104 break;
105 (void) unlink ((char *) cache_hashed);
106 }
107 FcStrListDone (list);
108 /* return FcFalse if something went wrong */
109 if (cache_dir)
110 return FcFalse;
111 return FcTrue;
112 }
113
114 static int
115 FcDirCacheOpenFile (const FcChar8 *cache_file, struct stat *file_stat)
116 {
117 int fd;
118
119 fd = open((char *) cache_file, O_RDONLY | O_BINARY);
120 if (fd < 0)
121 return fd;
122 if (fstat (fd, file_stat) < 0)
123 {
124 close (fd);
125 return -1;
126 }
127 return fd;
128 }
129
130 /*
131 * Look for a cache file for the specified dir. Attempt
132 * to use each one we find, stopping when the callback
133 * indicates success
134 */
135 static FcBool
136 FcDirCacheProcess (FcConfig *config, const FcChar8 *dir,
137 FcBool (*callback) (int fd, struct stat *stat, void *closure),
138 void *closure, FcChar8 **cache_file_ret)
139 {
140 int fd = -1;
141 FcChar8 cache_base[CACHEBASE_LEN];
142 FcStrList *list;
143 FcChar8 *cache_dir;
144 struct stat file_stat, dir_stat;
145 FcBool ret = FcFalse;
146
147 if (stat ((char *) dir, &dir_stat) < 0)
148 return FcFalse;
149
150 FcDirCacheBasename (dir, cache_base);
151
152 list = FcStrListCreate (config->cacheDirs);
153 if (!list)
154 return FcFalse;
155
156 while ((cache_dir = FcStrListNext (list)))
157 {
158 FcChar8 *cache_hashed = FcStrPlus (cache_dir, cache_base);
159 if (!cache_hashed)
160 break;
161 fd = FcDirCacheOpenFile (cache_hashed, &file_stat);
162 if (fd >= 0) {
163 if (dir_stat.st_mtime <= file_stat.st_mtime)
164 {
165 ret = (*callback) (fd, &file_stat, closure);
166 if (ret)
167 {
168 if (cache_file_ret)
169 *cache_file_ret = cache_hashed;
170 else
171 FcStrFree (cache_hashed);
172 close (fd);
173 break;
174 }
175 }
176 close (fd);
177 }
178 FcStrFree (cache_hashed);
179 }
180 FcStrListDone (list);
181
182 return ret;
183 }
184
185 static void
186 FcDirCacheDispose (FcCache *cache)
187 {
188 switch (cache->magic) {
189 case FC_CACHE_MAGIC_ALLOC:
190 free (cache);
191 break;
192 case FC_CACHE_MAGIC_MMAP:
193 #if defined(HAVE_MMAP) || defined(__CYGWIN__)
194 munmap (cache, cache->size);
195 #elif defined(_WIN32)
196 UnmapViewOfFile (cache);
197 #endif
198 break;
199 }
200 }
201
202 #define FC_CACHE_MIN_MMAP 1024
203
204 #define FC_CACHE_HASH_SIZE 67
205
206 typedef struct _FcCacheBucket FcCacheBucket;
207
208 struct _FcCacheBucket {
209 FcCacheBucket *next;
210 FcCache *cache;
211 dev_t cache_dev;
212 ino_t cache_ino;
213 time_t cache_mtime;
214 };
215
216 static FcCacheBucket *FcCacheBuckets[FC_CACHE_HASH_SIZE];
217
218 static uint32_t
219 FcCacheStatHash (struct stat *cache_stat)
220 {
221 return ((uint32_t) cache_stat->st_dev ^
222 (uint32_t) cache_stat->st_ino ^
223 (uint32_t) cache_stat->st_mtime);
224 }
225
226 static FcCache *
227 FcCacheLookup (struct stat *cache_stat)
228 {
229 uint32_t hash = FcCacheStatHash(cache_stat);
230 FcCacheBucket **bucket = &FcCacheBuckets[hash % FC_CACHE_HASH_SIZE];
231 FcCacheBucket *b;
232
233 for (b = *bucket; b; b = b->next)
234 if (b->cache_dev == cache_stat->st_dev &&
235 b->cache_ino == cache_stat->st_ino &&
236 b->cache_mtime == cache_stat->st_mtime)
237 return b->cache;
238 return NULL;
239 }
240
241 static FcBool
242 FcCacheRecord (FcCache *cache, struct stat *cache_stat)
243 {
244 uint32_t hash = FcCacheStatHash(cache_stat);
245 FcCacheBucket **bucket = &FcCacheBuckets[hash % FC_CACHE_HASH_SIZE];
246 FcCacheBucket *b;
247
248 b = malloc (sizeof (FcCacheBucket));
249 if (!b)
250 return FcFalse;
251 b->next = *bucket;
252 b->cache = cache;
253 b->cache_dev = cache_stat->st_dev;
254 b->cache_ino = cache_stat->st_ino;
255 b->cache_mtime = cache_stat->st_mtime;
256 *bucket = b;
257 return FcTrue;
258 }
259
260 void
261 FcCacheFini (void)
262 {
263 int i;
264 FcCacheBucket *b, *next;
265
266 for (i = 0; i < FC_CACHE_HASH_SIZE; i++)
267 {
268 for (b = FcCacheBuckets[i]; b; b = next)
269 {
270 next = b->next;
271 FcDirCacheDispose (b->cache);
272 free (b);
273 }
274 FcCacheBuckets[i] = NULL;
275 }
276 }
277
278 /*
279 * Map a cache file into memory
280 */
281 static FcCache *
282 FcDirCacheMapFd (int fd, struct stat *fd_stat)
283 {
284 FcCache *cache;
285 FcBool allocated = FcFalse;
286
287 if (fd_stat->st_size < sizeof (FcCache))
288 return NULL;
289 cache = FcCacheLookup (fd_stat);
290 if (cache)
291 return cache;
292 /*
293 * For small cache files, just read them into memory
294 */
295 if (fd_stat->st_size >= FC_CACHE_MIN_MMAP)
296 {
297 #if defined(HAVE_MMAP) || defined(__CYGWIN__)
298 cache = mmap (0, fd_stat->st_size, PROT_READ, MAP_SHARED, fd, 0);
299 #elif defined(_WIN32)
300 {
301 HANDLE hFileMap;
302
303 cache = NULL;
304 hFileMap = CreateFileMapping((HANDLE) _get_osfhandle(fd), NULL,
305 PAGE_READONLY, 0, 0, NULL);
306 if (hFileMap != NULL)
307 {
308 cache = MapViewOfFile (hFileMap, FILE_MAP_READ, 0, 0, size);
309 CloseHandle (hFileMap);
310 }
311 }
312 #endif
313 }
314 if (!cache)
315 {
316 cache = malloc (fd_stat->st_size);
317 if (!cache)
318 return NULL;
319
320 if (read (fd, cache, fd_stat->st_size) != fd_stat->st_size)
321 {
322 free (cache);
323 return NULL;
324 }
325 allocated = FcTrue;
326 }
327 if (cache->magic != FC_CACHE_MAGIC_MMAP ||
328 cache->version < FC_CACHE_CONTENT_VERSION ||
329 cache->size != fd_stat->st_size ||
330 !FcCacheRecord (cache, fd_stat))
331 {
332 if (allocated)
333 free (cache);
334 else
335 {
336 #if defined(HAVE_MMAP) || defined(__CYGWIN__)
337 munmap (cache, fd_stat->st_size);
338 #elif defined(_WIN32)
339 UnmapViewOfFile (cache);
340 #endif
341 }
342 return NULL;
343 }
344
345 /* Mark allocated caches so they're freed rather than unmapped */
346 if (allocated)
347 cache->magic = FC_CACHE_MAGIC_ALLOC;
348
349 return cache;
350 }
351
352 void
353 FcDirCacheUnload (FcCache *cache)
354 {
355 /* Can't free or unmap the cache as apps may point into it */
356 }
357
358 static FcBool
359 FcDirCacheMapHelper (int fd, struct stat *fd_stat, void *closure)
360 {
361 FcCache *cache = FcDirCacheMapFd (fd, fd_stat);
362
363 if (!cache)
364 return FcFalse;
365 *((FcCache **) closure) = cache;
366 return FcTrue;
367 }
368
369 FcCache *
370 FcDirCacheLoad (const FcChar8 *dir, FcConfig *config, FcChar8 **cache_file)
371 {
372 FcCache *cache = NULL;
373
374 if (!FcDirCacheProcess (config, dir,
375 FcDirCacheMapHelper,
376 &cache, cache_file))
377 return NULL;
378 return cache;
379 }
380
381 FcCache *
382 FcDirCacheLoadFile (const FcChar8 *cache_file, struct stat *file_stat)
383 {
384 int fd;
385 FcCache *cache;
386
387 fd = FcDirCacheOpenFile (cache_file, file_stat);
388 if (fd < 0)
389 return NULL;
390 cache = FcDirCacheMapFd (fd, file_stat);
391 close (fd);
392 return cache;
393 }
394
395 /*
396 * Validate a cache file by reading the header and checking
397 * the magic number and the size field
398 */
399 static FcBool
400 FcDirCacheValidateHelper (int fd, struct stat *fd_stat, void *closure)
401 {
402 FcBool ret = FcTrue;
403 FcCache c;
404
405 if (read (fd, &c, sizeof (FcCache)) != sizeof (FcCache))
406 ret = FcFalse;
407 else if (c.magic != FC_CACHE_MAGIC_MMAP)
408 ret = FcFalse;
409 else if (c.version < FC_CACHE_CONTENT_VERSION)
410 ret = FcFalse;
411 else if (fd_stat->st_size != c.size)
412 ret = FcFalse;
413 return ret;
414 }
415
416 static FcBool
417 FcDirCacheValidConfig (const FcChar8 *dir, FcConfig *config)
418 {
419 return FcDirCacheProcess (config, dir,
420 FcDirCacheValidateHelper,
421 NULL, NULL);
422 }
423
424 FcBool
425 FcDirCacheValid (const FcChar8 *dir)
426 {
427 FcConfig *config;
428
429 config = FcConfigGetCurrent ();
430 if (!config)
431 return FcFalse;
432
433 return FcDirCacheValidConfig (dir, config);
434 }
435
436 /*
437 * Build a cache structure from the given contents
438 */
439 FcCache *
440 FcDirCacheBuild (FcFontSet *set, const FcChar8 *dir, FcStrSet *dirs)
441 {
442 FcSerialize *serialize = FcSerializeCreate ();
443 FcCache *cache;
444 int i;
445 intptr_t cache_offset;
446 intptr_t dirs_offset;
447 FcChar8 *dir_serialize;
448 intptr_t *dirs_serialize;
449 FcFontSet *set_serialize;
450
451 if (!serialize)
452 return NULL;
453 /*
454 * Space for cache structure
455 */
456 cache_offset = FcSerializeReserve (serialize, sizeof (FcCache));
457 /*
458 * Directory name
459 */
460 if (!FcStrSerializeAlloc (serialize, dir))
461 goto bail1;
462 /*
463 * Subdirs
464 */
465 dirs_offset = FcSerializeAlloc (serialize, dirs, dirs->num * sizeof (FcChar8 *));
466 for (i = 0; i < dirs->num; i++)
467 if (!FcStrSerializeAlloc (serialize, dirs->strs[i]))
468 goto bail1;
469
470 /*
471 * Patterns
472 */
473 if (!FcFontSetSerializeAlloc (serialize, set))
474 goto bail1;
475
476 /* Serialize layout complete. Now allocate space and fill it */
477 cache = malloc (serialize->size);
478 if (!cache)
479 goto bail1;
480 /* shut up valgrind */
481 memset (cache, 0, serialize->size);
482
483 serialize->linear = cache;
484
485 cache->magic = FC_CACHE_MAGIC_ALLOC;
486 cache->version = FC_CACHE_CONTENT_VERSION;
487 cache->size = serialize->size;
488
489 /*
490 * Serialize directory name
491 */
492 dir_serialize = FcStrSerialize (serialize, dir);
493 if (!dir_serialize)
494 goto bail2;
495 cache->dir = FcPtrToOffset (cache, dir_serialize);
496
497 /*
498 * Serialize sub dirs
499 */
500 dirs_serialize = FcSerializePtr (serialize, dirs);
501 if (!dirs_serialize)
502 goto bail2;
503 cache->dirs = FcPtrToOffset (cache, dirs_serialize);
504 cache->dirs_count = dirs->num;
505 for (i = 0; i < dirs->num; i++)
506 {
507 FcChar8 *d_serialize = FcStrSerialize (serialize, dirs->strs[i]);
508 if (!d_serialize)
509 goto bail2;
510 dirs_serialize[i] = FcPtrToOffset (dirs_serialize, d_serialize);
511 }
512
513 /*
514 * Serialize font set
515 */
516 set_serialize = FcFontSetSerialize (serialize, set);
517 if (!set_serialize)
518 goto bail2;
519 cache->set = FcPtrToOffset (cache, set_serialize);
520
521 FcSerializeDestroy (serialize);
522
523 return cache;
524
525 bail2:
526 free (cache);
527 bail1:
528 FcSerializeDestroy (serialize);
529 return NULL;
530 }
531
532 static FcBool
533 FcMakeDirectory (const FcChar8 *dir)
534 {
535 FcChar8 *parent;
536 FcBool ret;
537
538 if (strlen ((char *) dir) == 0)
539 return FcFalse;
540
541 parent = FcStrDirname (dir);
542 if (!parent)
543 return FcFalse;
544 if (access ((char *) parent, W_OK|X_OK) == 0)
545 ret = mkdir ((char *) dir, 0777) == 0;
546 else if (access ((char *) parent, F_OK) == -1)
547 ret = FcMakeDirectory (parent) && (mkdir ((char *) dir, 0777) == 0);
548 else
549 ret = FcFalse;
550 FcStrFree (parent);
551 return ret;
552 }
553
554 /* write serialized state to the cache file */
555 FcBool
556 FcDirCacheWrite (FcCache *cache, FcConfig *config)
557 {
558 FcChar8 *dir = FcCacheDir (cache);
559 FcChar8 cache_base[CACHEBASE_LEN];
560 FcChar8 *cache_hashed;
561 int fd;
562 FcAtomic *atomic;
563 FcStrList *list;
564 FcChar8 *cache_dir = NULL;
565 FcChar8 *test_dir;
566 int magic;
567 int written;
568
569 /*
570 * Write it to the first directory in the list which is writable
571 */
572
573 list = FcStrListCreate (config->cacheDirs);
574 if (!list)
575 return FcFalse;
576 while ((test_dir = FcStrListNext (list))) {
577 if (access ((char *) test_dir, W_OK|X_OK) == 0)
578 {
579 cache_dir = test_dir;
580 break;
581 }
582 else
583 {
584 /*
585 * If the directory doesn't exist, try to create it
586 */
587 if (access ((char *) test_dir, F_OK) == -1) {
588 if (FcMakeDirectory (test_dir))
589 {
590 cache_dir = test_dir;
591 break;
592 }
593 }
594 }
595 }
596 FcStrListDone (list);
597 if (!cache_dir)
598 return FcFalse;
599
600 FcDirCacheBasename (dir, cache_base);
601 cache_hashed = FcStrPlus (cache_dir, cache_base);
602 if (!cache_hashed)
603 return FcFalse;
604
605 if (FcDebug () & FC_DBG_CACHE)
606 printf ("FcDirCacheWriteDir dir \"%s\" file \"%s\"\n",
607 dir, cache_hashed);
608
609 atomic = FcAtomicCreate ((FcChar8 *)cache_hashed);
610 if (!atomic)
611 goto bail1;
612
613 if (!FcAtomicLock (atomic))
614 goto bail3;
615
616 fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT | O_BINARY, 0666);
617 if (fd == -1)
618 goto bail4;
619
620 /* Temporarily switch magic to MMAP while writing to file */
621 magic = cache->magic;
622 if (magic != FC_CACHE_MAGIC_MMAP)
623 cache->magic = FC_CACHE_MAGIC_MMAP;
624
625 /*
626 * Write cache contents to file
627 */
628 written = write (fd, cache, cache->size);
629
630 /* Switch magic back */
631 if (magic != FC_CACHE_MAGIC_MMAP)
632 cache->magic = magic;
633
634 if (written != cache->size)
635 {
636 perror ("write cache");
637 goto bail5;
638 }
639
640 close(fd);
641 if (!FcAtomicReplaceOrig(atomic))
642 goto bail4;
643 FcStrFree (cache_hashed);
644 FcAtomicUnlock (atomic);
645 FcAtomicDestroy (atomic);
646 return FcTrue;
647
648 bail5:
649 close (fd);
650 bail4:
651 FcAtomicUnlock (atomic);
652 bail3:
653 FcAtomicDestroy (atomic);
654 bail1:
655 FcStrFree (cache_hashed);
656 return FcFalse;
657 }
658
659 /*
660 * Hokey little macro trick to permit the definitions of C functions
661 * with the same name as CPP macros
662 */
663 #define args(x...) (x)
664
665 const FcChar8 *
666 FcCacheDir args(const FcCache *c)
667 {
668 return FcCacheDir (c);
669 }
670
671 FcFontSet *
672 FcCacheCopySet args(const FcCache *c)
673 {
674 FcFontSet *old = FcCacheSet (c);
675 FcFontSet *new = FcFontSetCreate ();
676 int i;
677
678 if (!new)
679 return NULL;
680 for (i = 0; i < old->nfont; i++)
681 if (!FcFontSetAdd (new, FcFontSetFont (old, i)))
682 {
683 FcFontSetDestroy (new);
684 return NULL;
685 }
686 return new;
687 }
688
689 const FcChar8 *
690 FcCacheSubdir args(const FcCache *c, int i)
691 {
692 return FcCacheSubdir (c, i);
693 }
694
695 int
696 FcCacheNumSubdir args(const FcCache *c)
697 {
698 return c->dirs_count;
699 }
700
701 int
702 FcCacheNumFont args(const FcCache *c)
703 {
704 return FcCacheSet(c)->nfont;
705 }
706
707 /*
708 * This code implements the MD5 message-digest algorithm.
709 * The algorithm is due to Ron Rivest. This code was
710 * written by Colin Plumb in 1993, no copyright is claimed.
711 * This code is in the public domain; do with it what you wish.
712 *
713 * Equivalent code is available from RSA Data Security, Inc.
714 * This code has been tested against that, and is equivalent,
715 * except that you don't need to include two pages of legalese
716 * with every copy.
717 *
718 * To compute the message digest of a chunk of bytes, declare an
719 * MD5Context structure, pass it to MD5Init, call MD5Update as
720 * needed on buffers full of bytes, and then call MD5Final, which
721 * will fill a supplied 16-byte array with the digest.
722 */
723
724 #ifndef HIGHFIRST
725 #define byteReverse(buf, len) /* Nothing */
726 #else
727 /*
728 * Note: this code is harmless on little-endian machines.
729 */
730 void byteReverse(unsigned char *buf, unsigned longs)
731 {
732 FcChar32 t;
733 do {
734 t = (FcChar32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
735 ((unsigned) buf[1] << 8 | buf[0]);
736 *(FcChar32 *) buf = t;
737 buf += 4;
738 } while (--longs);
739 }
740 #endif
741
742 /*
743 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
744 * initialization constants.
745 */
746 static void MD5Init(struct MD5Context *ctx)
747 {
748 ctx->buf[0] = 0x67452301;
749 ctx->buf[1] = 0xefcdab89;
750 ctx->buf[2] = 0x98badcfe;
751 ctx->buf[3] = 0x10325476;
752
753 ctx->bits[0] = 0;
754 ctx->bits[1] = 0;
755 }
756
757 /*
758 * Update context to reflect the concatenation of another buffer full
759 * of bytes.
760 */
761 static void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len)
762 {
763 FcChar32 t;
764
765 /* Update bitcount */
766
767 t = ctx->bits[0];
768 if ((ctx->bits[0] = t + ((FcChar32) len << 3)) < t)
769 ctx->bits[1]++; /* Carry from low to high */
770 ctx->bits[1] += len >> 29;
771
772 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
773
774 /* Handle any leading odd-sized chunks */
775
776 if (t) {
777 unsigned char *p = (unsigned char *) ctx->in + t;
778
779 t = 64 - t;
780 if (len < t) {
781 memcpy(p, buf, len);
782 return;
783 }
784 memcpy(p, buf, t);
785 byteReverse(ctx->in, 16);
786 MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
787 buf += t;
788 len -= t;
789 }
790 /* Process data in 64-byte chunks */
791
792 while (len >= 64) {
793 memcpy(ctx->in, buf, 64);
794 byteReverse(ctx->in, 16);
795 MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
796 buf += 64;
797 len -= 64;
798 }
799
800 /* Handle any remaining bytes of data. */
801
802 memcpy(ctx->in, buf, len);
803 }
804
805 /*
806 * Final wrapup - pad to 64-byte boundary with the bit pattern
807 * 1 0* (64-bit count of bits processed, MSB-first)
808 */
809 static void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
810 {
811 unsigned count;
812 unsigned char *p;
813
814 /* Compute number of bytes mod 64 */
815 count = (ctx->bits[0] >> 3) & 0x3F;
816
817 /* Set the first char of padding to 0x80. This is safe since there is
818 always at least one byte free */
819 p = ctx->in + count;
820 *p++ = 0x80;
821
822 /* Bytes of padding needed to make 64 bytes */
823 count = 64 - 1 - count;
824
825 /* Pad out to 56 mod 64 */
826 if (count < 8) {
827 /* Two lots of padding: Pad the first block to 64 bytes */
828 memset(p, 0, count);
829 byteReverse(ctx->in, 16);
830 MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
831
832 /* Now fill the next block with 56 bytes */
833 memset(ctx->in, 0, 56);
834 } else {
835 /* Pad block to 56 bytes */
836 memset(p, 0, count - 8);
837 }
838 byteReverse(ctx->in, 14);
839
840 /* Append length in bits and transform */
841 ((FcChar32 *) ctx->in)[14] = ctx->bits[0];
842 ((FcChar32 *) ctx->in)[15] = ctx->bits[1];
843
844 MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
845 byteReverse((unsigned char *) ctx->buf, 4);
846 memcpy(digest, ctx->buf, 16);
847 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
848 }
849
850
851 /* The four core functions - F1 is optimized somewhat */
852
853 /* #define F1(x, y, z) (x & y | ~x & z) */
854 #define F1(x, y, z) (z ^ (x & (y ^ z)))
855 #define F2(x, y, z) F1(z, x, y)
856 #define F3(x, y, z) (x ^ y ^ z)
857 #define F4(x, y, z) (y ^ (x | ~z))
858
859 /* This is the central step in the MD5 algorithm. */
860 #define MD5STEP(f, w, x, y, z, data, s) \
861 ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
862
863 /*
864 * The core of the MD5 algorithm, this alters an existing MD5 hash to
865 * reflect the addition of 16 longwords of new data. MD5Update blocks
866 * the data and converts bytes into longwords for this routine.
867 */
868 static void MD5Transform(FcChar32 buf[4], FcChar32 in[16])
869 {
870 register FcChar32 a, b, c, d;
871
872 a = buf[0];
873 b = buf[1];
874 c = buf[2];
875 d = buf[3];
876
877 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
878 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
879 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
880 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
881 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
882 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
883 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
884 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
885 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
886 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
887 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
888 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
889 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
890 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
891 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
892 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
893
894 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
895 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
896 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
897 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
898 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
899 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
900 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
901 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
902 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
903 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
904 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
905 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
906 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
907 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
908 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
909 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
910
911 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
912 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
913 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
914 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
915 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
916 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
917 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
918 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
919 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
920 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
921 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
922 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
923 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
924 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
925 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
926 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
927
928 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
929 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
930 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
931 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
932 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
933 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
934 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
935 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
936 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
937 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
938 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
939 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
940 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
941 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
942 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
943 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
944
945 buf[0] += a;
946 buf[1] += b;
947 buf[2] += c;
948 buf[3] += d;
949 }
http://fontconfig.org/