src/fccache.c

   1 /*
   2  * $RCSId: xc/lib/fontconfig/src/fccache.c,v 1.12 2002/08/22 07:36:44 keithp Exp $
   3  *
   4  * Copyright © 2000 Keith Packard
   5  * Copyright © 2005 Patrick Lam
   6  *
   7  * Permission to use, copy, modify, distribute, and sell this software and its
   8  * documentation for any purpose is hereby granted without fee, provided that
   9  * the above copyright notice appear in all copies and that both that
  10  * copyright notice and this permission notice appear in supporting
  11  * documentation, and that the name of Keith Packard not be used in
  12  * advertising or publicity pertaining to distribution of the software without
  13  * specific, written prior permission.  Keith Packard makes no
  14  * representations about the suitability of this software for any purpose.  It
  15  * is provided "as is" without express or implied warranty.
  16  *
  17  * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  18  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  19  * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  20  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  21  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  22  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  23  * PERFORMANCE OF THIS SOFTWARE.
  24  */
  25
  26 #include <fcntl.h>
  27 #include <dirent.h>
  28 #include <string.h>
  29 #include <sys/mman.h>
  30 #include <sys/utsname.h>
  31 #include <sys/types.h>
  32 #include <unistd.h>
  33 #include "fcint.h"
  34 #include <unistd.h>
  35
  36 #define ENDIAN_TEST 0x12345678
  37 #define MACHINE_SIGNATURE_SIZE 9 + 5*20 + 1
  38
  39 static int
  40 FcDirCacheOpen (const FcChar8 * dir);
  41
  42 static char *
  43 FcDirCacheHashName (char * cache_file, int collisions);
  44
  45 static off_t
  46 FcCacheSkipToArch (int fd, const char * arch);
  47
  48 static FcBool
  49 FcCacheCopyOld (int fd, int fd_orig, off_t start);
  50
  51 static void *
  52 FcDirCacheProduce (FcFontSet *set, FcCache * metadata);
  53
  54 static FcBool
  55 FcDirCacheConsume (int fd, const char * dir, FcFontSet *set, FcConfig *config);
  56
  57 static int
  58 FcCacheNextOffset(off_t w);
  59
  60 static char *
  61 FcCacheMachineSignature (void);
  62
  63 static FcBool
  64 FcCacheHaveBank (int bank);
  65
  66 static void
  67 FcCacheAddBankDir (int bank, const char * dir);
  68
  69 struct MD5Context {
  70         FcChar32 buf[4];
  71         FcChar32 bits[2];
  72         unsigned char in[64];
  73 };
  74
  75 static void MD5Init(struct MD5Context *ctx);
  76 static void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len);
  77 static void MD5Final(unsigned char digest[16], struct MD5Context *ctx);
  78 static void MD5Transform(FcChar32 buf[4], FcChar32 in[16]);
  79
  80 #define FC_DBG_CACHE_REF    1024
  81
  82 static char *
  83 FcCacheReadString (int fd, char *dest, int len)
  84 {
  85     FcChar8     c;
  86     FcBool      escape;
  87     int         size;
  88     int         i;
  89
  90     if (len == 0)
  91         return 0;
  92
  93     size = len;
  94     i = 0;
  95     escape = FcFalse;
  96     while (read (fd, &c, 1) == 1)
  97     {
  98         if (!escape)
  99         {
 100             switch (c) {
 101             case '"':
 102                 c = '\0';
 103                 break;
 104             case '\\':
 105                 escape = FcTrue;
 106                 continue;
 107             }
 108         }
 109         if (i == size)
 110         {
 111             dest[i++] = 0;
 112             return dest;
 113         }
 114         dest[i++] = c;
 115         if (c == '\0')
 116             return dest;
 117         escape = FcFalse;
 118     }
 119     return 0;
 120 }
 121
 122 static void
 123 FcCacheSkipString (int fd)
 124 {
 125     FcChar8     c;
 126     FcBool      escape;
 127
 128     escape = FcFalse;
 129     while (read (fd, &c, 1) == 1)
 130     {
 131         if (!escape)
 132         {
 133             switch (c) {
 134             case '"':
 135                 c = '\0';
 136                 break;
 137             case '\\':
 138                 escape = FcTrue;
 139                 continue;
 140             }
 141         }
 142         if (c == '\0')
 143             return;
 144         escape = FcFalse;
 145     }
 146     return;
 147 }
 148
 149 static FcBool
 150 FcCacheWriteString (int fd, const char *chars)
 151 {
 152     if (write (fd, chars, strlen(chars)+1) != strlen(chars)+1)
 153         return FcFalse;
 154     return FcTrue;
 155 }
 156
 157 static void
 158 FcGlobalCacheDirDestroy (FcGlobalCacheDir *d)
 159 {
 160     FcStrSetDestroy (d->subdirs);
 161     FcMemFree (FC_MEM_STRING, strlen (d->name)+1);
 162     free (d->name);
 163     FcMemFree (FC_MEM_CACHE, sizeof (FcGlobalCacheDir));
 164     free (d);
 165 }
 166
 167 FcGlobalCache *
 168 FcGlobalCacheCreate (void)
 169 {
 170     FcGlobalCache   *cache;
 171
 172     cache = malloc (sizeof (FcGlobalCache));
 173     if (!cache)
 174         return 0;
 175     FcMemAlloc (FC_MEM_CACHE, sizeof (FcGlobalCache));
 176     cache->dirs = 0;
 177     cache->updated = FcFalse;
 178     cache->fd = -1;
 179     return cache;
 180 }
 181
 182 void
 183 FcGlobalCacheDestroy (FcGlobalCache *cache)
 184 {
 185     FcGlobalCacheDir    *d, *next;
 186
 187     for (d = cache->dirs; d; d = next)
 188     {
 189         next = d->next;
 190         FcGlobalCacheDirDestroy (d);
 191     }
 192     FcMemFree (FC_MEM_CACHE, sizeof (FcGlobalCache));
 193     free (cache);
 194 }
 195
 196 void
 197 FcGlobalCacheLoad (FcGlobalCache    *cache,
 198                    FcStrSet         *staleDirs,
 199                    const FcChar8    *cache_file,
 200                    FcConfig         *config)
 201 {
 202     char                name_buf[FC_MAX_FILE_LEN];
 203     FcGlobalCacheDir    *d, *next;
 204     FcFileTime          config_time = FcConfigModifiedTime (config);
 205     char                * current_arch_machine_name;
 206     char                candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 207     off_t               current_arch_start;
 208
 209     struct stat         cache_stat, dir_stat;
 210     char                subdirName[FC_MAX_FILE_LEN + 1 + 12 + 1];
 211
 212     if (stat ((char *) cache_file, &cache_stat) < 0)
 213         return;
 214
 215     cache->fd = open ((char *) cache_file, O_RDONLY);
 216     if (cache->fd == -1)
 217         return;
 218
 219     cache->updated = FcFalse;
 220
 221     if (!FcCacheReadString (cache->fd, name_buf, sizeof (name_buf)))
 222         return;
 223     if (strcmp (name_buf, FC_GLOBAL_MAGIC_COOKIE) != 0)
 224         return;
 225
 226     current_arch_machine_name = FcCacheMachineSignature ();
 227     current_arch_start = FcCacheSkipToArch(cache->fd,
 228                                            current_arch_machine_name);
 229     if (current_arch_start < 0)
 230         goto bail_and_destroy;
 231
 232     lseek (cache->fd, current_arch_start, SEEK_SET);
 233     if (!FcCacheReadString (cache->fd, candidate_arch_machine_name,
 234                             sizeof (candidate_arch_machine_name)))
 235         goto bail_and_destroy;
 236     if (strlen(candidate_arch_machine_name) == 0)
 237         goto bail_and_destroy;
 238
 239     while (1)
 240     {
 241         off_t targ;
 242
 243         if (!FcCacheReadString (cache->fd, name_buf, sizeof (name_buf)) || !strlen(name_buf))
 244             break;
 245
 246         /* Directory must be older than the global cache file; also
 247            cache must be newer than the config file. */
 248         if (stat ((char *) name_buf, &dir_stat) < 0 ||
 249             dir_stat.st_mtime > cache_stat.st_mtime ||
 250             (config_time.set && cache_stat.st_mtime < config_time.time))
 251         {
 252             FcCache md;
 253
 254             FcStrSetAdd (staleDirs, FcStrCopy ((FcChar8 *)name_buf));
 255             read (cache->fd, &md, sizeof (FcCache));
 256             lseek (cache->fd, FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + md.count, SEEK_SET);
 257             continue;
 258         }
 259
 260         d = malloc (sizeof (FcGlobalCacheDir));
 261         if (!d)
 262             goto bail1;
 263
 264         d->next = cache->dirs;
 265         cache->dirs = d;
 266
 267         d->name = (char *)FcStrCopy ((FcChar8 *)name_buf);
 268         d->ent = 0;
 269         d->offset = lseek (cache->fd, 0, SEEK_CUR);
 270
 271         d->subdirs = FcStrSetCreate();
 272         while (strlen(FcCacheReadString (cache->fd, subdirName, sizeof (subdirName))) > 0)
 273             FcStrSetAdd (d->subdirs, (FcChar8 *)subdirName);
 274
 275         if (read (cache->fd, &d->metadata, sizeof (FcCache)) != sizeof (FcCache))
 276             goto bail1;
 277         targ = FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + d->metadata.count;
 278         if (lseek (cache->fd, targ, SEEK_SET) != targ)
 279             goto bail1;
 280     }
 281     return;
 282
 283  bail1:
 284     for (d = cache->dirs; d; d = next)
 285     {
 286         next = d->next;
 287         free (d);
 288     }
 289     cache->dirs = 0;
 290
 291     close (cache->fd);
 292     cache->fd = -1;
 293     return;
 294
 295  bail_and_destroy:
 296     close (cache->fd);
 297     cache->fd = -1;
 298
 299     if (stat ((char *) cache_file, &cache_stat) == 0)
 300         unlink ((char *)cache_file);
 301
 302     return;
 303
 304 }
 305
 306 FcBool
 307 FcGlobalCacheReadDir (FcFontSet *set, FcStrSet *dirs, FcGlobalCache * cache, const char *dir, FcConfig *config)
 308 {
 309     FcGlobalCacheDir *d;
 310     FcBool ret = FcFalse;
 311
 312     if (cache->fd == -1)
 313         return FcFalse;
 314
 315     if (!(dir = (char *)FcConfigNormalizeFontDir (config, (FcChar8 *)dir)))
 316         return FcFalse; /* non-existing directory */
 317
 318     for (d = cache->dirs; d; d = d->next)
 319     {
 320         if (strncmp (d->name, dir, strlen(dir)) == 0)
 321         {
 322             lseek (cache->fd, d->offset, SEEK_SET);
 323             if (!FcDirCacheConsume (cache->fd, d->name, set, config))
 324                 return FcFalse;
 325             if (strcmp (d->name, dir) == 0)
 326                 ret = FcTrue;
 327         }
 328     }
 329
 330     return ret;
 331 }
 332
 333 FcBool
 334 FcGlobalCacheUpdate (FcGlobalCache  *cache,
 335                      FcStrSet       *dirs,
 336                      const char     *name,
 337                      FcFontSet      *set,
 338                      FcConfig       *config)
 339 {
 340     FcGlobalCacheDir    *d;
 341     int                 i;
 342
 343     name = (char *)FcConfigNormalizeFontDir (config, (FcChar8 *)name);
 344     for (d = cache->dirs; d; d = d->next)
 345     {
 346         if (strcmp(d->name, name) == 0)
 347             break;
 348     }
 349
 350     if (!d)
 351     {
 352         d = malloc (sizeof (FcGlobalCacheDir));
 353         if (!d)
 354             return FcFalse;
 355         d->next = cache->dirs;
 356         cache->dirs = d;
 357     }
 358
 359     cache->updated = FcTrue;
 360
 361     d->name = (char *)FcStrCopy ((FcChar8 *)name);
 362     d->ent = FcDirCacheProduce (set, &d->metadata);
 363     d->offset = 0;
 364     d->subdirs = FcStrSetCreate();
 365     for (i = 0; i < dirs->num; i++)
 366         FcStrSetAdd (d->subdirs, dirs->strs[i]);
 367     return FcTrue;
 368 }
 369
 370 FcBool
 371 FcGlobalCacheSave (FcGlobalCache    *cache,
 372                    const FcChar8    *cache_file,
 373                    FcConfig         *config)
 374 {
 375     int                 fd, fd_orig, i;
 376     FcGlobalCacheDir    *dir;
 377     FcAtomic            *atomic;
 378     off_t               current_arch_start = 0, truncate_to;
 379     char                * current_arch_machine_name, * header;
 380
 381     if (!cache->updated)
 382         return FcTrue;
 383
 384 #if defined (HAVE_GETUID) && defined (HAVE_GETEUID)
 385     /* Set-UID programs can't safely update the cache */
 386     if (getuid () != geteuid ())
 387         return FcFalse;
 388 #endif
 389
 390     atomic = FcAtomicCreate (cache_file);
 391     if (!atomic)
 392         return FcFalse;
 393
 394     if (!FcAtomicLock (atomic))
 395         goto bail1;
 396     fd = open ((char *) FcAtomicNewFile(atomic), O_RDWR | O_CREAT,
 397                S_IRUSR | S_IWUSR);
 398     if (fd == -1)
 399         goto bail2;
 400     FcCacheWriteString (fd, FC_GLOBAL_MAGIC_COOKIE);
 401
 402     fd_orig = open ((char *) FcAtomicOrigFile(atomic), O_RDONLY);
 403
 404     current_arch_machine_name = FcCacheMachineSignature ();
 405     if (fd_orig == -1)
 406         current_arch_start = 0;
 407     else
 408         current_arch_start = FcCacheSkipToArch (fd_orig,
 409                                                 current_arch_machine_name);
 410
 411     if (current_arch_start < 0)
 412     {
 413         off_t i = lseek(fd_orig, 0, SEEK_END);
 414         if (i < strlen (FC_GLOBAL_MAGIC_COOKIE)+1)
 415             i = strlen (FC_GLOBAL_MAGIC_COOKIE)+1;
 416         current_arch_start = FcCacheNextOffset (i);
 417     }
 418
 419     if (!FcCacheCopyOld(fd, fd_orig, current_arch_start))
 420         goto bail3;
 421
 422     close (fd_orig);
 423     fd_orig = -1;
 424
 425     current_arch_start = lseek(fd, 0, SEEK_CUR);
 426     if (ftruncate (fd, current_arch_start) == -1)
 427         goto bail3;
 428
 429     header = malloc (10 + strlen (current_arch_machine_name));
 430     if (!header)
 431         goto bail3;
 432
 433     truncate_to = current_arch_start + strlen(current_arch_machine_name) + 11;
 434     for (dir = cache->dirs; dir; dir = dir->next)
 435     {
 436         truncate_to += strlen(dir->name) + 1;
 437         truncate_to += sizeof (FcCache);
 438         truncate_to = FcCacheNextOffset (truncate_to);
 439         truncate_to += dir->metadata.count;
 440
 441         for (i = 0; i < dir->subdirs->size; i++)
 442             truncate_to += strlen((char *)dir->subdirs->strs[i]) + 1;
 443         truncate_to ++;
 444     }
 445     truncate_to -= current_arch_start;
 446
 447     sprintf (header, "%8x ", (int)truncate_to);
 448     strcat (header, current_arch_machine_name);
 449     if (!FcCacheWriteString (fd, header))
 450         goto bail4;
 451
 452     for (dir = cache->dirs; dir; dir = dir->next)
 453     {
 454         if (dir->name)
 455         {
 456             const char * d = (const char *)FcConfigNormalizeFontDir (config, (const FcChar8 *)dir->name);
 457
 458             FcCacheWriteString (fd, d);
 459
 460             for (i = 0; i < dir->subdirs->size; i++)
 461                 FcCacheWriteString (fd, (char *)dir->subdirs->strs[i]);
 462             FcCacheWriteString (fd, "");
 463
 464             write (fd, &dir->metadata, sizeof(FcCache));
 465             lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_CUR)), SEEK_SET);
 466             write (fd, dir->ent, dir->metadata.count);
 467             free (dir->ent);
 468         }
 469     }
 470     FcCacheWriteString (fd, "");
 471
 472     if (close (fd) == -1)
 473         goto bail25;
 474
 475     if (!FcAtomicReplaceOrig (atomic))
 476         goto bail25;
 477
 478     FcAtomicUnlock (atomic);
 479     FcAtomicDestroy (atomic);
 480
 481     cache->updated = FcFalse;
 482     return FcTrue;
 483
 484  bail4:
 485     free (header);
 486  bail3:
 487     if (fd_orig != -1)
 488         close (fd_orig);
 489
 490     close (fd);
 491  bail25:
 492     FcAtomicDeleteNew (atomic);
 493  bail2:
 494     FcAtomicUnlock (atomic);
 495  bail1:
 496     FcAtomicDestroy (atomic);
 497     return FcFalse;
 498 }
 499
 500 /*
 501  * Find the next presumably-mmapable offset after the supplied file
 502  * position.
 503  */
 504 static int
 505 FcCacheNextOffset(off_t w)
 506 {
 507     static long pagesize = -1;
 508     if (pagesize == -1)
 509         pagesize = sysconf(_SC_PAGESIZE);
 510     if (w % pagesize == 0)
 511         return w;
 512     else
 513         return ((w / pagesize)+1)*pagesize;
 514 }
 515
 516 /* return the address of the segment for the provided arch,
 517  * or -1 if arch not found */
 518 static off_t
 519 FcCacheSkipToArch (int fd, const char * arch)
 520 {
 521     char candidate_arch_machine_name_count[MACHINE_SIGNATURE_SIZE + 9];
 522     char * candidate_arch;
 523     off_t current_arch_start = 0;
 524
 525     lseek (fd, 0, SEEK_SET);
 526     FcCacheSkipString (fd);
 527     current_arch_start = lseek (fd, 0, SEEK_CUR);
 528
 529     /* skip arches that are not the current arch */
 530     while (1)
 531     {
 532         long bs;
 533
 534         if (lseek (fd, current_arch_start, SEEK_SET) != current_arch_start)
 535             return -1;
 536
 537         if (FcCacheReadString (fd, candidate_arch_machine_name_count,
 538                                 sizeof (candidate_arch_machine_name_count)) == 0)
 539             return -1;
 540         if (!strlen(candidate_arch_machine_name_count))
 541             return -1;
 542         bs = strtol(candidate_arch_machine_name_count, &candidate_arch, 16);
 543
 544         // count = 0 should probably be distinguished from the !bs condition
 545         if (!bs || bs < strlen (candidate_arch_machine_name_count))
 546             return -1;
 547
 548         candidate_arch++; /* skip leading space */
 549
 550         if (strcmp (candidate_arch, arch)==0)
 551             return current_arch_start;
 552         current_arch_start += bs;
 553     }
 554
 555     return -1;
 556 }
 557
 558 /* Cuts out the segment at the file pointer (moves everything else
 559  * down to cover it), and leaves the file pointer at the end of the
 560  * file. */
 561 static FcBool
 562 FcCacheCopyOld (int fd, int fd_orig, off_t start)
 563 {
 564     char * buf = malloc (8192);
 565     char candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 566     long bs;
 567     int c, bytes_skipped;
 568     off_t loc;
 569
 570     if (!buf)
 571         return FcFalse;
 572
 573     loc = 0;
 574     lseek (fd, 0, SEEK_SET); lseek (fd_orig, 0, SEEK_SET);
 575     do
 576     {
 577         int b = 8192;
 578         if (loc + b > start)
 579             b = start - loc;
 580
 581         if ((c = read (fd_orig, buf, b)) <= 0)
 582             break;
 583         if (write (fd, buf, c) < 0)
 584             goto bail;
 585
 586         loc += c;
 587     }
 588     while (c > 0);
 589
 590     lseek (fd, start, SEEK_SET);
 591     if (FcCacheReadString (fd, candidate_arch_machine_name,
 592                            sizeof (candidate_arch_machine_name)) == 0)
 593         goto done;
 594     if (!strlen(candidate_arch_machine_name))
 595         goto done;
 596
 597     bs = strtol(candidate_arch_machine_name, 0, 16);
 598     if (bs == 0)
 599         goto done;
 600
 601     bytes_skipped = 0;
 602     do
 603     {
 604         lseek (fd, start+bs+bytes_skipped, SEEK_SET);
 605         if ((c = read (fd, buf, 8192)) <= 0)
 606             break;
 607         lseek (fd, start+bytes_skipped, SEEK_SET);
 608         if (write (fd, buf, c) < 0)
 609             goto bail;
 610         bytes_skipped += c;
 611     }
 612     while (c > 0);
 613     lseek (fd, start+bytes_skipped, SEEK_SET);
 614
 615  done:
 616     free (buf);
 617     return FcTrue;
 618
 619  bail:
 620     free (buf);
 621     return FcFalse;
 622 }
 623
 624 /* Does not check that the cache has the appropriate arch section. */
 625 /* Also, this can be fooled if the original location has a stale
 626  * cache, and the hashed location has an up-to-date cache.  Oh well,
 627  * sucks to be you in that case! */
 628 FcBool
 629 FcDirCacheValid (const FcChar8 *dir)
 630 {
 631     struct stat file_stat, dir_stat;
 632     int         fd;
 633
 634     if (stat ((char *) dir, &dir_stat) < 0)
 635         return FcFalse;
 636
 637     fd = FcDirCacheOpen (dir);
 638
 639     if (fd < 0)
 640         goto bail;
 641     if (fstat (fd, &file_stat) < 0)
 642         goto bail;
 643
 644     close (fd);
 645
 646     /*
 647      * If the directory has been modified more recently than
 648      * the cache file, the cache is not valid
 649      */
 650     if (dir_stat.st_mtime > file_stat.st_mtime)
 651         return FcFalse;
 652
 653     return FcTrue;
 654
 655  bail:
 656     close (fd);
 657     return FcFalse;
 658 }
 659
 660 /* Assumes that the cache file in 'dir' exists.
 661  * Checks that the cache has the appropriate arch section. */
 662 FcBool
 663 FcDirCacheHasCurrentArch (const FcChar8 *dir)
 664 {
 665     int         fd;
 666     off_t       current_arch_start;
 667     char        *current_arch_machine_name;
 668
 669     fd = FcDirCacheOpen (dir);
 670     if (fd < 0)
 671         goto bail;
 672
 673     current_arch_machine_name = FcCacheMachineSignature();
 674     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 675     close (fd);
 676
 677     if (current_arch_start < 0)
 678         return FcFalse;
 679
 680     return FcTrue;
 681
 682  bail:
 683     return FcFalse;
 684 }
 685
 686 FcBool
 687 FcDirCacheUnlink (const FcChar8 *dir, FcConfig *config)
 688 {
 689     char        *cache_file;
 690     char        *cache_hashed = 0;
 691     int         fd, collisions;
 692     struct stat cache_stat;
 693     char        name_buf[FC_MAX_FILE_LEN];
 694
 695     dir = FcConfigNormalizeFontDir (config, dir);
 696     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 697     if (!cache_file)
 698         return FcFalse;
 699
 700     /* First remove normal cache file. */
 701     if (stat ((char *) cache_file, &cache_stat) == 0 &&
 702         unlink ((char *)cache_file) != 0)
 703         goto bail;
 704
 705     /* Next remove any applicable hashed files. */
 706     fd = -1; collisions = 0;
 707     do
 708     {
 709         if (cache_hashed)
 710             FcStrFree ((FcChar8 *)cache_hashed);
 711
 712         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
 713         if (!cache_hashed)
 714             goto bail;
 715
 716         if (fd > 0)
 717             close (fd);
 718         fd = open(cache_hashed, O_RDONLY);
 719         if (fd == -1)
 720         {
 721             FcStrFree ((FcChar8 *)cache_file);
 722             return FcTrue;
 723         }
 724
 725         if (!FcCacheReadString (fd, name_buf, sizeof (name_buf)) || !strlen(name_buf))
 726         {
 727             FcStrFree ((FcChar8 *)cache_hashed);
 728             goto bail;
 729         }
 730     } while (strcmp (name_buf, cache_file) != 0);
 731
 732     FcStrFree ((FcChar8 *)cache_file);
 733     close (fd);
 734
 735     if (stat ((char *) cache_hashed, &cache_stat) == 0 &&
 736         unlink ((char *)cache_hashed) != 0)
 737     {
 738         FcStrFree ((FcChar8 *)cache_hashed);
 739         goto bail;
 740     }
 741
 742     FcStrFree ((FcChar8 *)cache_hashed);
 743     return FcTrue;
 744
 745  bail:
 746     FcStrFree ((FcChar8 *)cache_file);
 747     return FcFalse;
 748 }
 749
 750 static int
 751 FcCacheReadDirs (FcConfig * config, FcGlobalCache * cache,
 752                  FcStrList *list, FcFontSet * set)
 753 {
 754     int                 ret = 0;
 755     FcChar8             *dir;
 756     FcChar8             *file, *base;
 757     FcStrSet            *subdirs;
 758     FcStrList           *sublist;
 759     struct stat         statb;
 760
 761     /*
 762      * Read in the results from 'list'.
 763      */
 764     while ((dir = FcStrListNext (list)))
 765     {
 766         if (!FcConfigAcceptFilename (config, dir))
 767             continue;
 768
 769         /* freed below */
 770         file = (FcChar8 *) malloc (strlen ((char *) dir) + 1 + FC_MAX_FILE_LEN + 1);
 771         if (!file)
 772             return FcFalse;
 773
 774         strcpy ((char *) file, (char *) dir);
 775         strcat ((char *) file, "/");
 776         base = file + strlen ((char *) file);
 777
 778         subdirs = FcStrSetCreate ();
 779         if (!subdirs)
 780         {
 781             fprintf (stderr, "Can't create directory set\n");
 782             ret++;
 783             free (file);
 784             continue;
 785         }
 786
 787         if (access ((char *) dir, X_OK) < 0)
 788         {
 789             switch (errno) {
 790             case ENOENT:
 791             case ENOTDIR:
 792             case EACCES:
 793                 break;
 794             default:
 795                 fprintf (stderr, "\"%s\": ", dir);
 796                 perror ("");
 797                 ret++;
 798             }
 799             FcStrSetDestroy (subdirs);
 800             free (file);
 801             continue;
 802         }
 803         if (stat ((char *) dir, &statb) == -1)
 804         {
 805             fprintf (stderr, "\"%s\": ", dir);
 806             perror ("");
 807             FcStrSetDestroy (subdirs);
 808             ret++;
 809             free (file);
 810             continue;
 811         }
 812         if (!S_ISDIR (statb.st_mode))
 813         {
 814             fprintf (stderr, "\"%s\": not a directory, skipping\n", dir);
 815             FcStrSetDestroy (subdirs);
 816             free (file);
 817             continue;
 818         }
 819         if (!FcDirCacheValid (dir) || !FcDirCacheRead (set, subdirs, dir, config))
 820         {
 821             if (FcDebug () & FC_DBG_FONTSET)
 822                 printf ("cache scan dir %s\n", dir);
 823
 824             FcDirScanConfig (set, subdirs, cache,
 825                              config->blanks, dir, FcFalse, config);
 826         }
 827         sublist = FcStrListCreate (subdirs);
 828         FcStrSetDestroy (subdirs);
 829         if (!sublist)
 830         {
 831             fprintf (stderr, "Can't create subdir list in \"%s\"\n", dir);
 832             ret++;
 833             free (file);
 834             continue;
 835         }
 836         ret += FcCacheReadDirs (config, cache, sublist, set);
 837         free (file);
 838     }
 839     FcStrListDone (list);
 840     return ret;
 841 }
 842
 843 FcFontSet *
 844 FcCacheRead (FcConfig *config, FcGlobalCache * cache)
 845 {
 846     FcFontSet * s = FcFontSetCreate();
 847     if (!s)
 848         return 0;
 849
 850     if (FcCacheReadDirs (config, cache, FcConfigGetConfigDirs (config), s))
 851         goto bail;
 852
 853     return s;
 854
 855  bail:
 856     FcFontSetDestroy (s);
 857     return 0;
 858 }
 859
 860 static const char bin2hex[] = { '0', '1', '2', '3',
 861                                 '4', '5', '6', '7',
 862                                 '8', '9', 'a', 'b',
 863                                 'c', 'd', 'e', 'f' };
 864
 865 static char *
 866 FcDirCacheHashName (char * cache_file, int collisions)
 867 {
 868     unsigned char       hash[16], hex_hash[33];
 869     char                *cache_hashed;
 870     unsigned char       uscore = '_';
 871     int                 cnt, i;
 872     FcChar8             *tmp;
 873     struct MD5Context   ctx;
 874
 875     MD5Init (&ctx);
 876     MD5Update (&ctx, (unsigned char *)cache_file, strlen (cache_file));
 877
 878     for (i = 0; i < collisions; i++)
 879         MD5Update (&ctx, &uscore, 1);
 880
 881     MD5Final (hash, &ctx);
 882
 883     for (cnt = 0; cnt < 16; ++cnt)
 884     {
 885         hex_hash[2*cnt] = bin2hex[hash[cnt] >> 4];
 886         hex_hash[2*cnt+1] = bin2hex[hash[cnt] & 0xf];
 887     }
 888     hex_hash[32] = 0;
 889
 890     tmp = FcStrPlus ((FcChar8 *)hex_hash, (FcChar8 *)FC_CACHE_SUFFIX);
 891     if (!tmp)
 892         return 0;
 893
 894     cache_hashed = (char *)FcStrPlus ((FcChar8 *)PKGCACHEDIR"/", tmp);
 895     free (tmp);
 896
 897     return cache_hashed;
 898 }
 899
 900 /* Opens the hashed name for cache_file.
 901  * This would fail in the unlikely event of a collision and subsequent
 902  * removal of the file which originally caused the collision. */
 903 static int
 904 FcDirCacheOpen (const FcChar8 *dir)
 905 {
 906     FcBool      found;
 907     int         fd = -1, collisions = 0;
 908     char        *cache_file, *cache_hashed;
 909     char        name_buf[FC_MAX_FILE_LEN];
 910     struct stat dir_stat;
 911
 912     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 913     if (!cache_file)
 914         return -1;
 915
 916     fd = open(cache_file, O_RDONLY);
 917     if (fd != -1)
 918         return fd;
 919
 920     if (stat ((char *)dir, &dir_stat) == -1)
 921         return -1;
 922
 923     found = FcFalse;
 924     do
 925     {
 926         struct stat c;
 927         FcChar8 * name_buf_dir;
 928
 929         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
 930         if (!cache_hashed)
 931         {
 932             FcStrFree ((FcChar8 *)cache_file);
 933             return -1;
 934         }
 935
 936         if (fd > 0)
 937             close (fd);
 938         fd = open(cache_hashed, O_RDONLY);
 939         FcStrFree ((FcChar8 *)cache_hashed);
 940
 941         if (fd == -1)
 942         {
 943             FcStrFree ((FcChar8 *)cache_file);
 944             return -1;
 945         }
 946         if (!FcCacheReadString (fd, name_buf, sizeof (name_buf)) || !strlen(name_buf))
 947             goto bail;
 948
 949         name_buf_dir = FcStrDirname ((FcChar8 *)name_buf);
 950         if (stat ((char *)name_buf_dir, &c) == -1)
 951         {
 952             FcStrFree (name_buf_dir);
 953             continue;
 954         }
 955         FcStrFree (name_buf_dir);
 956         found = (c.st_ino == dir_stat.st_ino) && (c.st_dev == dir_stat.st_dev);
 957     } while (!found);
 958     FcStrFree ((FcChar8 *)cache_file);
 959     return fd;
 960
 961  bail:
 962     FcStrFree ((FcChar8 *)cache_file);
 963     close (fd);
 964     return -1;
 965 }
 966
 967 /* read serialized state from the cache file */
 968 FcBool
 969 FcDirCacheRead (FcFontSet * set, FcStrSet * dirs, const FcChar8 *dir, FcConfig *config)
 970 {
 971     int         fd;
 972     char        *current_arch_machine_name;
 973     char        candidate_arch_machine_name[9+MACHINE_SIGNATURE_SIZE];
 974     off_t       current_arch_start = 0;
 975     char        subdirName[FC_MAX_FILE_LEN + 1 + 12 + 1];
 976
 977     fd = FcDirCacheOpen (dir);
 978     if (fd < 0)
 979         goto bail;
 980
 981     current_arch_machine_name = FcCacheMachineSignature();
 982     current_arch_start = FcCacheSkipToArch(fd,
 983                                            current_arch_machine_name);
 984     if (current_arch_start < 0)
 985         goto bail1;
 986
 987     lseek (fd, current_arch_start, SEEK_SET);
 988     if (FcCacheReadString (fd, candidate_arch_machine_name,
 989                            sizeof (candidate_arch_machine_name)) == 0)
 990         goto bail1;
 991
 992     while (FcCacheReadString (fd, subdirName, sizeof (subdirName)) && strlen (subdirName) > 0)
 993         FcStrSetAdd (dirs, (FcChar8 *)subdirName);
 994
 995     if (!FcDirCacheConsume (fd, (const char *)dir, set, config))
 996         goto bail1;
 997
 998     close(fd);
 999     return FcTrue;
1000
1001  bail1:
1002     close (fd);
1003  bail:
1004     return FcFalse;
1005 }
1006
1007 static FcBool
1008 FcDirCacheConsume (int fd, const char * dir, FcFontSet *set, FcConfig *config)
1009 {
1010     FcCache metadata;
1011     void * current_dir_block;
1012     off_t pos;
1013
1014     read(fd, &metadata, sizeof(FcCache));
1015     if (metadata.magic != FC_CACHE_MAGIC)
1016         return FcFalse;
1017
1018     if (!metadata.count)
1019     {
1020         pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
1021         lseek (fd, pos, SEEK_SET);
1022         if (config)
1023             FcConfigAddFontDir (config, (FcChar8 *)dir);
1024         return FcTrue;
1025     }
1026
1027     pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
1028     current_dir_block = mmap (0, metadata.count,
1029                               PROT_READ, MAP_SHARED, fd, pos);
1030     lseek (fd, pos+metadata.count, SEEK_SET);
1031     if (current_dir_block == MAP_FAILED)
1032         return FcFalse;
1033
1034     FcCacheAddBankDir (metadata.bank, dir);
1035     if (config)
1036         FcConfigAddFontDir (config, (FcChar8 *)dir);
1037
1038     if (!FcFontSetUnserialize (&metadata, set, current_dir_block))
1039         return FcFalse;
1040
1041     return FcTrue;
1042 }
1043
1044 static void *
1045 FcDirCacheProduce (FcFontSet *set, FcCache *metadata)
1046 {
1047     void * current_dir_block, * final_dir_block;
1048     static unsigned int rand_state = 0;
1049     int bank, needed_bytes_no_align;
1050
1051     if (!rand_state)
1052         rand_state = time(0L);
1053     bank = rand_r(&rand_state);
1054
1055     while (FcCacheHaveBank(bank))
1056         bank = rand_r(&rand_state);
1057
1058     memset (metadata, 0, sizeof(FcCache));
1059     FcFontSetNewBank();
1060     needed_bytes_no_align = FcFontSetNeededBytes (set);
1061     metadata->count = needed_bytes_no_align +
1062         FcFontSetNeededBytesAlign ();
1063     metadata->magic = FC_CACHE_MAGIC;
1064     metadata->bank = bank;
1065
1066     if (!needed_bytes_no_align) /* not a failure, no fonts to write */
1067     {
1068         /* no, you don't really need to write any bytes at all. */
1069         metadata->count = 0;
1070         return 0;
1071     }
1072
1073     current_dir_block = malloc (metadata->count);
1074     if (!current_dir_block)
1075         goto bail;
1076     // shut up valgrind
1077     memset (current_dir_block, 0, metadata->count);
1078     final_dir_block = FcFontSetDistributeBytes (metadata, current_dir_block);
1079
1080     if ((void *)((char *)current_dir_block+metadata->count) < final_dir_block)
1081         goto bail;
1082
1083     if (!FcFontSetSerialize (bank, set))
1084         goto bail;
1085
1086     return current_dir_block;
1087
1088  bail:
1089     free (current_dir_block);
1090     return 0;
1091 }
1092
1093 /* write serialized state to the cache file */
1094 FcBool
1095 FcDirCacheWrite (FcFontSet *set, FcStrSet *dirs, const FcChar8 *dir)
1096 {
1097     char            *cache_file;
1098     char            *cache_hashed;
1099     int             fd, fd_orig, i, dirs_count;
1100     FcAtomic        *atomic;
1101     FcCache         metadata;
1102     off_t           current_arch_start = 0, truncate_to;
1103     char            name_buf[FC_MAX_FILE_LEN];
1104     int             collisions;
1105
1106     char            *current_arch_machine_name, * header;
1107     void            *current_dir_block = 0;
1108
1109     dir = FcConfigNormalizeFontDir (FcConfigGetCurrent(), dir);
1110     if (!dir)
1111         return FcFalse;
1112
1113     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
1114     if (!cache_file)
1115         goto bail;
1116
1117     /* Ensure that we're not trampling a cache for some other dir. */
1118     /* This is slightly different from FcDirCacheOpen, since it
1119      * needs the filename, not the file descriptor. */
1120     fd = -1; collisions = 0;
1121     do
1122     {
1123         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
1124         if (!cache_hashed)
1125             goto bail0;
1126
1127         if (fd > 0)
1128             close (fd);
1129         fd = open(cache_hashed, O_RDONLY);
1130         if (fd == -1)
1131             break;
1132         if(!FcCacheReadString (fd, name_buf, sizeof (name_buf)) || !strlen(name_buf))
1133         {
1134             close (fd);
1135             break;
1136         }
1137         close (fd);
1138
1139         if (strcmp (name_buf, cache_file) != 0)
1140             continue;
1141     } while (0);
1142
1143     current_dir_block = FcDirCacheProduce (set, &metadata);
1144
1145     if (metadata.count && !current_dir_block)
1146         goto bail1;
1147
1148     if (FcDebug () & FC_DBG_CACHE)
1149         printf ("FcDirCacheWriteDir cache_file \"%s\"\n", cache_file);
1150
1151     atomic = FcAtomicCreate ((FcChar8 *)cache_hashed);
1152     if (!atomic)
1153         goto bail1;
1154
1155     if (!FcAtomicLock (atomic))
1156     {
1157         /* Now try rewriting the original version of the file. */
1158         FcAtomicDestroy (atomic);
1159
1160         atomic = FcAtomicCreate ((FcChar8 *)cache_file);
1161         fd_orig = open (cache_file, O_RDONLY);
1162         if (fd_orig == -1)
1163             fd_orig = open((char *)FcAtomicOrigFile (atomic), O_RDONLY);
1164
1165         fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT, 0666);
1166         if (fd == -1)
1167             goto bail2;
1168     }
1169
1170     /* In all cases, try opening the real location of the cache file first. */
1171     /* (even if that's not atomic.) */
1172     fd_orig = open (cache_file, O_RDONLY);
1173     if (fd_orig == -1)
1174         fd_orig = open((char *)FcAtomicOrigFile (atomic), O_RDONLY);
1175
1176     fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT, 0666);
1177     if (fd == -1)
1178         goto bail3;
1179
1180     FcCacheWriteString (fd, cache_file);
1181
1182     current_arch_machine_name = FcCacheMachineSignature ();
1183     current_arch_start = 0;
1184
1185     if (fd_orig != -1)
1186         current_arch_start =
1187             FcCacheSkipToArch(fd_orig, current_arch_machine_name);
1188
1189     if (current_arch_start < 0)
1190     {
1191         off_t i = lseek(fd_orig, 0, SEEK_END);
1192         if (i < strlen (FC_GLOBAL_MAGIC_COOKIE)+1)
1193             i = strlen (FC_GLOBAL_MAGIC_COOKIE)+1;
1194         current_arch_start = FcCacheNextOffset (i);
1195     }
1196
1197     if (fd_orig != -1 && !FcCacheCopyOld(fd, fd_orig, current_arch_start))
1198         goto bail4;
1199
1200     if (fd_orig != -1)
1201         close (fd_orig);
1202
1203     current_arch_start = lseek(fd, 0, SEEK_CUR);
1204     if (ftruncate (fd, current_arch_start) == -1)
1205         goto bail4;
1206
1207     /* allocate space for subdir names in this block */
1208     dirs_count = 0;
1209     for (i = 0; i < dirs->size; i++)
1210         dirs_count += strlen((char *)dirs->strs[i]) + 1;
1211     dirs_count ++;
1212
1213     /* now write the address of the next offset */
1214     truncate_to = FcCacheNextOffset (FcCacheNextOffset (current_arch_start + sizeof (FcCache) + dirs_count) + metadata.count) - current_arch_start;
1215     header = malloc (10 + strlen (current_arch_machine_name));
1216     if (!header)
1217         goto bail4;
1218     sprintf (header, "%8x ", (int)truncate_to);
1219     strcat (header, current_arch_machine_name);
1220     if (!FcCacheWriteString (fd, header))
1221         goto bail5;
1222
1223     for (i = 0; i < dirs->size; i++)
1224         FcCacheWriteString (fd, (char *)dirs->strs[i]);
1225     FcCacheWriteString (fd, "");
1226
1227     write (fd, &metadata, sizeof(FcCache));
1228     if (metadata.count)
1229     {
1230         lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_END)), SEEK_SET);
1231         write (fd, current_dir_block, metadata.count);
1232         free (current_dir_block);
1233     }
1234
1235     /* this actually serves to pad out the cache file, if needed */
1236     if (ftruncate (fd, current_arch_start + truncate_to) == -1)
1237         goto bail5;
1238
1239     free (header);
1240     close(fd);
1241     if (!FcAtomicReplaceOrig(atomic))
1242         goto bail5;
1243     FcStrFree ((FcChar8 *)cache_hashed);
1244     FcStrFree ((FcChar8 *)cache_file);
1245     FcAtomicUnlock (atomic);
1246     FcAtomicDestroy (atomic);
1247     return FcTrue;
1248
1249  bail5:
1250     free (header);
1251  bail4:
1252     close (fd);
1253  bail3:
1254     FcAtomicUnlock (atomic);
1255  bail2:
1256     FcAtomicDestroy (atomic);
1257  bail1:
1258     FcStrFree ((FcChar8 *)cache_hashed);
1259  bail0:
1260     unlink ((char *)cache_file);
1261     FcStrFree ((FcChar8 *)cache_file);
1262     if (current_dir_block)
1263         free (current_dir_block);
1264  bail:
1265     return FcFalse;
1266 }
1267
1268 static char *
1269 FcCacheMachineSignature ()
1270 {
1271     static char buf[MACHINE_SIGNATURE_SIZE];
1272     int32_t magic = ENDIAN_TEST;
1273     char * m = (char *)&magic;
1274
1275     sprintf (buf, "%2x%2x%2x%2x "
1276              "%4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x "
1277              "%4x %4x %4x %4x %4x %4x %4x %4x\n",
1278              m[0], m[1], m[2], m[3],
1279              (unsigned int)sizeof (char),
1280              (unsigned int)sizeof (char *),
1281              (unsigned int)sizeof (int),
1282              (unsigned int)sizeof (FcPattern),
1283              (unsigned int)sizeof (FcPatternEltPtr),
1284              (unsigned int)sizeof (struct _FcPatternElt *),
1285              (unsigned int)sizeof (FcPatternElt),
1286              (unsigned int)sizeof (FcObjectPtr),
1287              (unsigned int)sizeof (FcValueListPtr),
1288              (unsigned int)sizeof (FcValue),
1289              (unsigned int)sizeof (FcValueBinding),
1290              (unsigned int)sizeof (struct _FcValueList *),
1291              (unsigned int)sizeof (FcCharSet),
1292              (unsigned int)sizeof (FcCharLeaf **),
1293              (unsigned int)sizeof (FcChar16 *),
1294              (unsigned int)sizeof (FcChar16),
1295              (unsigned int)sizeof (FcCharLeaf),
1296              (unsigned int)sizeof (FcChar32),
1297              (unsigned int)sizeof (FcCache),
1298              (unsigned int)sysconf(_SC_PAGESIZE));
1299
1300     return buf;
1301 }
1302
1303 static int banks_ptr = 0, banks_alloc = 0;
1304 int * _fcBankId = 0, * _fcBankIdx = 0;
1305 static const char ** bankDirs = 0;
1306
1307 static FcBool
1308 FcCacheHaveBank (int bank)
1309 {
1310     int i;
1311
1312     if (bank < FC_BANK_FIRST)
1313         return FcTrue;
1314
1315     for (i = 0; i < banks_ptr; i++)
1316         if (_fcBankId[i] == bank)
1317             return FcTrue;
1318
1319     return FcFalse;
1320 }
1321
1322 int
1323 FcCacheBankToIndexMTF (int bank)
1324 {
1325     int i, j;
1326
1327     for (i = 0; i < banks_ptr; i++)
1328         if (_fcBankId[_fcBankIdx[i]] == bank)
1329         {
1330             int t = _fcBankIdx[i];
1331
1332             for (j = i; j > 0; j--)
1333                 _fcBankIdx[j] = _fcBankIdx[j-1];
1334             _fcBankIdx[0] = t;
1335             return t;
1336         }
1337
1338     if (banks_ptr >= banks_alloc)
1339     {
1340         int * b, * bidx;
1341         const char ** bds;
1342
1343         b = realloc (_fcBankId, (banks_alloc + 4) * sizeof(int));
1344         if (!b)
1345             return -1;
1346         _fcBankId = b;
1347
1348         bidx = realloc (_fcBankIdx, (banks_alloc + 4) * sizeof(int));
1349         if (!bidx)
1350             return -1;
1351         _fcBankIdx = bidx;
1352
1353         bds = realloc (bankDirs, (banks_alloc + 4) * sizeof (char *));
1354         if (!bds)
1355             return -1;
1356         bankDirs = bds;
1357
1358         banks_alloc += 4;
1359     }
1360
1361     i = banks_ptr++;
1362     _fcBankId[i] = bank;
1363     _fcBankIdx[i] = i;
1364     return i;
1365 }
1366
1367 static void
1368 FcCacheAddBankDir (int bank, const char * dir)
1369 {
1370     int bi = FcCacheBankToIndexMTF (bank);
1371
1372     if (bi < 0)
1373         return;
1374
1375     bankDirs[bi] = (const char *)FcStrCopy ((FcChar8 *)dir);
1376 }
1377
1378 const char *
1379 FcCacheFindBankDir (int bank)
1380 {
1381     int bi = FcCacheBankToIndex (bank);
1382     return bankDirs[bi];
1383 }
1384
1385 /*
1386  * This code implements the MD5 message-digest algorithm.
1387  * The algorithm is due to Ron Rivest.  This code was
1388  * written by Colin Plumb in 1993, no copyright is claimed.
1389  * This code is in the public domain; do with it what you wish.
1390  *
1391  * Equivalent code is available from RSA Data Security, Inc.
1392  * This code has been tested against that, and is equivalent,
1393  * except that you don't need to include two pages of legalese
1394  * with every copy.
1395  *
1396  * To compute the message digest of a chunk of bytes, declare an
1397  * MD5Context structure, pass it to MD5Init, call MD5Update as
1398  * needed on buffers full of bytes, and then call MD5Final, which
1399  * will fill a supplied 16-byte array with the digest.
1400  */
1401
1402 #ifndef HIGHFIRST
1403 #define byteReverse(buf, len)   /* Nothing */
1404 #else
1405 /*
1406  * Note: this code is harmless on little-endian machines.
1407  */
1408 void byteReverse(unsigned char *buf, unsigned longs)
1409 {
1410     FcChar32 t;
1411     do {
1412         t = (FcChar32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
1413             ((unsigned) buf[1] << 8 | buf[0]);
1414         *(FcChar32 *) buf = t;
1415         buf += 4;
1416     } while (--longs);
1417 }
1418 #endif
1419
1420 /*
1421  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
1422  * initialization constants.
1423  */
1424 static void MD5Init(struct MD5Context *ctx)
1425 {
1426     ctx->buf[0] = 0x67452301;
1427     ctx->buf[1] = 0xefcdab89;
1428     ctx->buf[2] = 0x98badcfe;
1429     ctx->buf[3] = 0x10325476;
1430
1431     ctx->bits[0] = 0;
1432     ctx->bits[1] = 0;
1433 }
1434
1435 /*
1436  * Update context to reflect the concatenation of another buffer full
1437  * of bytes.
1438  */
1439 static void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len)
1440 {
1441     FcChar32 t;
1442
1443     /* Update bitcount */
1444
1445     t = ctx->bits[0];
1446     if ((ctx->bits[0] = t + ((FcChar32) len << 3)) < t)
1447         ctx->bits[1]++;         /* Carry from low to high */
1448     ctx->bits[1] += len >> 29;
1449
1450     t = (t >> 3) & 0x3f;        /* Bytes already in shsInfo->data */
1451
1452     /* Handle any leading odd-sized chunks */
1453
1454     if (t) {
1455         unsigned char *p = (unsigned char *) ctx->in + t;
1456
1457         t = 64 - t;
1458         if (len < t) {
1459             memcpy(p, buf, len);
1460             return;
1461         }
1462         memcpy(p, buf, t);
1463         byteReverse(ctx->in, 16);
1464         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1465         buf += t;
1466         len -= t;
1467     }
1468     /* Process data in 64-byte chunks */
1469
1470     while (len >= 64) {
1471         memcpy(ctx->in, buf, 64);
1472         byteReverse(ctx->in, 16);
1473         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1474         buf += 64;
1475         len -= 64;
1476     }
1477
1478     /* Handle any remaining bytes of data. */
1479
1480     memcpy(ctx->in, buf, len);
1481 }
1482
1483 /*
1484  * Final wrapup - pad to 64-byte boundary with the bit pattern
1485  * 1 0* (64-bit count of bits processed, MSB-first)
1486  */
1487 static void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
1488 {
1489     unsigned count;
1490     unsigned char *p;
1491
1492     /* Compute number of bytes mod 64 */
1493     count = (ctx->bits[0] >> 3) & 0x3F;
1494
1495     /* Set the first char of padding to 0x80.  This is safe since there is
1496        always at least one byte free */
1497     p = ctx->in + count;
1498     *p++ = 0x80;
1499
1500     /* Bytes of padding needed to make 64 bytes */
1501     count = 64 - 1 - count;
1502
1503     /* Pad out to 56 mod 64 */
1504     if (count < 8) {
1505         /* Two lots of padding:  Pad the first block to 64 bytes */
1506         memset(p, 0, count);
1507         byteReverse(ctx->in, 16);
1508         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1509
1510         /* Now fill the next block with 56 bytes */
1511         memset(ctx->in, 0, 56);
1512     } else {
1513         /* Pad block to 56 bytes */
1514         memset(p, 0, count - 8);
1515     }
1516     byteReverse(ctx->in, 14);
1517
1518     /* Append length in bits and transform */
1519     ((FcChar32 *) ctx->in)[14] = ctx->bits[0];
1520     ((FcChar32 *) ctx->in)[15] = ctx->bits[1];
1521
1522     MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1523     byteReverse((unsigned char *) ctx->buf, 4);
1524     memcpy(digest, ctx->buf, 16);
1525     memset(ctx, 0, sizeof(ctx));        /* In case it's sensitive */
1526 }
1527
1528
1529 /* The four core functions - F1 is optimized somewhat */
1530
1531 /* #define F1(x, y, z) (x & y | ~x & z) */
1532 #define F1(x, y, z) (z ^ (x & (y ^ z)))
1533 #define F2(x, y, z) F1(z, x, y)
1534 #define F3(x, y, z) (x ^ y ^ z)
1535 #define F4(x, y, z) (y ^ (x | ~z))
1536
1537 /* This is the central step in the MD5 algorithm. */
1538 #define MD5STEP(f, w, x, y, z, data, s) \
1539         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
1540
1541 /*
1542  * The core of the MD5 algorithm, this alters an existing MD5 hash to
1543  * reflect the addition of 16 longwords of new data.  MD5Update blocks
1544  * the data and converts bytes into longwords for this routine.
1545  */
1546 static void MD5Transform(FcChar32 buf[4], FcChar32 in[16])
1547 {
1548     register FcChar32 a, b, c, d;
1549
1550     a = buf[0];
1551     b = buf[1];
1552     c = buf[2];
1553     d = buf[3];
1554
1555     MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
1556     MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
1557     MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
1558     MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
1559     MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
1560     MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
1561     MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
1562     MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
1563     MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
1564     MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
1565     MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
1566     MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
1567     MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
1568     MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
1569     MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
1570     MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
1571
1572     MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
1573     MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
1574     MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
1575     MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
1576     MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
1577     MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
1578     MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
1579     MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
1580     MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
1581     MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
1582     MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
1583     MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
1584     MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
1585     MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
1586     MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
1587     MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
1588
1589     MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
1590     MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
1591     MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
1592     MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
1593     MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
1594     MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
1595     MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
1596     MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
1597     MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
1598     MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
1599     MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
1600     MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
1601     MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
1602     MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
1603     MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
1604     MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
1605
1606     MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
1607     MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
1608     MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
1609     MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
1610     MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
1611     MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
1612     MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
1613     MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
1614     MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
1615     MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
1616     MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
1617     MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
1618     MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
1619     MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
1620     MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
1621     MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
1622
1623     buf[0] += a;
1624     buf[1] += b;
1625     buf[2] += c;
1626     buf[3] += d;
1627 }