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)) ||
 244             !strlen(name_buf))
 245             break;
 246
 247         /* Directory must be older than the global cache file; also
 248            cache must be newer than the config file. */
 249         if (stat ((char *) name_buf, &dir_stat) < 0 ||
 250             dir_stat.st_mtime > cache_stat.st_mtime ||
 251             (config_time.set && cache_stat.st_mtime < config_time.time))
 252         {
 253             FcCache md;
 254
 255             FcStrSetAdd (staleDirs, FcStrCopy ((FcChar8 *)name_buf));
 256             read (cache->fd, &md, sizeof (FcCache));
 257             lseek (cache->fd, FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + md.count, SEEK_SET);
 258             continue;
 259         }
 260
 261         d = malloc (sizeof (FcGlobalCacheDir));
 262         if (!d)
 263             goto bail1;
 264
 265         d->next = cache->dirs;
 266         cache->dirs = d;
 267
 268         d->name = (char *)FcStrCopy ((FcChar8 *)name_buf);
 269         d->ent = 0;
 270
 271         d->subdirs = FcStrSetCreate();
 272         do
 273         {
 274             if (!FcCacheReadString (cache->fd, subdirName,
 275                                     sizeof (subdirName)) ||
 276                 !strlen (subdirName))
 277                 break;
 278             FcStrSetAdd (d->subdirs, (FcChar8 *)subdirName);
 279         } while (1);
 280
 281         d->offset = lseek (cache->fd, 0, SEEK_CUR);
 282         if (read (cache->fd, &d->metadata, sizeof (FcCache)) != sizeof (FcCache))
 283             goto bail1;
 284         targ = FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + d->metadata.count;
 285         if (lseek (cache->fd, targ, SEEK_SET) != targ)
 286             goto bail1;
 287     }
 288     return;
 289
 290  bail1:
 291     for (d = cache->dirs; d; d = next)
 292     {
 293         next = d->next;
 294         free (d);
 295     }
 296     cache->dirs = 0;
 297
 298     close (cache->fd);
 299     cache->fd = -1;
 300     return;
 301
 302  bail_and_destroy:
 303     close (cache->fd);
 304     cache->fd = -1;
 305
 306     if (stat ((char *) cache_file, &cache_stat) == 0)
 307         unlink ((char *)cache_file);
 308
 309     return;
 310
 311 }
 312
 313 FcBool
 314 FcGlobalCacheReadDir (FcFontSet *set, FcStrSet *dirs, FcGlobalCache * cache, const char *dir, FcConfig *config)
 315 {
 316     FcGlobalCacheDir *d;
 317     FcBool ret = FcFalse;
 318
 319     if (cache->fd == -1)
 320         return FcFalse;
 321
 322     if (!(dir = (char *)FcConfigNormalizeFontDir (config, (FcChar8 *)dir)))
 323         return FcFalse; /* non-existing directory */
 324
 325     for (d = cache->dirs; d; d = d->next)
 326     {
 327         if (strncmp (d->name, dir, strlen(dir)) == 0)
 328         {
 329             lseek (cache->fd, d->offset, SEEK_SET);
 330             if (!FcDirCacheConsume (cache->fd, d->name, set, config))
 331                 return FcFalse;
 332             if (strcmp (d->name, dir) == 0)
 333                 ret = FcTrue;
 334         }
 335     }
 336
 337     return ret;
 338 }
 339
 340 FcBool
 341 FcGlobalCacheUpdate (FcGlobalCache  *cache,
 342                      FcStrSet       *dirs,
 343                      const char     *name,
 344                      FcFontSet      *set,
 345                      FcConfig       *config)
 346 {
 347     FcGlobalCacheDir    *d;
 348     int                 i;
 349
 350     name = (char *)FcConfigNormalizeFontDir (config, (FcChar8 *)name);
 351     for (d = cache->dirs; d; d = d->next)
 352     {
 353         if (strcmp(d->name, name) == 0)
 354             break;
 355     }
 356
 357     if (!d)
 358     {
 359         d = malloc (sizeof (FcGlobalCacheDir));
 360         if (!d)
 361             return FcFalse;
 362         d->next = cache->dirs;
 363         cache->dirs = d;
 364     }
 365
 366     cache->updated = FcTrue;
 367
 368     d->name = (char *)FcStrCopy ((FcChar8 *)name);
 369     d->ent = FcDirCacheProduce (set, &d->metadata);
 370     d->offset = 0;
 371     d->subdirs = FcStrSetCreate();
 372     for (i = 0; i < dirs->num; i++)
 373         FcStrSetAdd (d->subdirs, dirs->strs[i]);
 374     return FcTrue;
 375 }
 376
 377 FcBool
 378 FcGlobalCacheSave (FcGlobalCache    *cache,
 379                    const FcChar8    *cache_file,
 380                    FcConfig         *config)
 381 {
 382     int                 fd, fd_orig, i;
 383     FcGlobalCacheDir    *dir;
 384     FcAtomic            *atomic;
 385     off_t               current_arch_start = 0, truncate_to;
 386     char                * current_arch_machine_name, * header;
 387
 388     if (!cache->updated)
 389         return FcTrue;
 390
 391 #if defined (HAVE_GETUID) && defined (HAVE_GETEUID)
 392     /* Set-UID programs can't safely update the cache */
 393     if (getuid () != geteuid ())
 394         return FcFalse;
 395 #endif
 396
 397     atomic = FcAtomicCreate (cache_file);
 398     if (!atomic)
 399         return FcFalse;
 400
 401     if (!FcAtomicLock (atomic))
 402         goto bail1;
 403     fd = open ((char *) FcAtomicNewFile(atomic), O_RDWR | O_CREAT,
 404                S_IRUSR | S_IWUSR);
 405     if (fd == -1)
 406         goto bail2;
 407     FcCacheWriteString (fd, FC_GLOBAL_MAGIC_COOKIE);
 408
 409     fd_orig = open ((char *) FcAtomicOrigFile(atomic), O_RDONLY);
 410
 411     current_arch_machine_name = FcCacheMachineSignature ();
 412     if (fd_orig == -1)
 413         current_arch_start = 0;
 414     else
 415         current_arch_start = FcCacheSkipToArch (fd_orig,
 416                                                 current_arch_machine_name);
 417
 418     if (current_arch_start < 0)
 419     {
 420         off_t i = lseek(fd_orig, 0, SEEK_END);
 421         if (i < strlen (FC_GLOBAL_MAGIC_COOKIE)+1)
 422             i = strlen (FC_GLOBAL_MAGIC_COOKIE)+1;
 423         current_arch_start = FcCacheNextOffset (i);
 424     }
 425
 426     if (!FcCacheCopyOld(fd, fd_orig, current_arch_start))
 427         goto bail3;
 428
 429     close (fd_orig);
 430     fd_orig = -1;
 431
 432     current_arch_start = lseek(fd, 0, SEEK_CUR);
 433     if (ftruncate (fd, current_arch_start) == -1)
 434         goto bail3;
 435
 436     header = malloc (10 + strlen (current_arch_machine_name));
 437     if (!header)
 438         goto bail3;
 439
 440     truncate_to = current_arch_start + strlen(current_arch_machine_name) + 11;
 441     for (dir = cache->dirs; dir; dir = dir->next)
 442     {
 443         truncate_to += strlen(dir->name) + 1;
 444         truncate_to += sizeof (FcCache);
 445         truncate_to = FcCacheNextOffset (truncate_to);
 446         truncate_to += dir->metadata.count;
 447
 448         for (i = 0; i < dir->subdirs->size; i++)
 449             truncate_to += strlen((char *)dir->subdirs->strs[i]) + 1;
 450         truncate_to ++;
 451     }
 452     truncate_to -= current_arch_start;
 453
 454     sprintf (header, "%8x ", (int)truncate_to);
 455     strcat (header, current_arch_machine_name);
 456     if (!FcCacheWriteString (fd, header))
 457         goto bail4;
 458
 459     for (dir = cache->dirs; dir; dir = dir->next)
 460     {
 461         if (dir->name)
 462         {
 463             const char * d = (const char *)FcConfigNormalizeFontDir (config, (const FcChar8 *)dir->name);
 464
 465             FcCacheWriteString (fd, d);
 466
 467             for (i = 0; i < dir->subdirs->size; i++)
 468                 FcCacheWriteString (fd, (char *)dir->subdirs->strs[i]);
 469             FcCacheWriteString (fd, "");
 470
 471             write (fd, &dir->metadata, sizeof(FcCache));
 472             lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_CUR)), SEEK_SET);
 473             write (fd, dir->ent, dir->metadata.count);
 474             free (dir->ent);
 475         }
 476     }
 477     FcCacheWriteString (fd, "");
 478
 479     if (close (fd) == -1)
 480         goto bail25;
 481
 482     if (!FcAtomicReplaceOrig (atomic))
 483         goto bail25;
 484
 485     FcAtomicUnlock (atomic);
 486     FcAtomicDestroy (atomic);
 487
 488     cache->updated = FcFalse;
 489     return FcTrue;
 490
 491  bail4:
 492     free (header);
 493  bail3:
 494     if (fd_orig != -1)
 495         close (fd_orig);
 496
 497     close (fd);
 498  bail25:
 499     FcAtomicDeleteNew (atomic);
 500  bail2:
 501     FcAtomicUnlock (atomic);
 502  bail1:
 503     FcAtomicDestroy (atomic);
 504     return FcFalse;
 505 }
 506
 507 /*
 508  * Find the next presumably-mmapable offset after the supplied file
 509  * position.
 510  */
 511 static int
 512 FcCacheNextOffset(off_t w)
 513 {
 514     static long pagesize = -1;
 515     if (pagesize == -1)
 516         pagesize = sysconf(_SC_PAGESIZE);
 517     if (w % pagesize == 0)
 518         return w;
 519     else
 520         return ((w / pagesize)+1)*pagesize;
 521 }
 522
 523 /* return the address of the segment for the provided arch,
 524  * or -1 if arch not found */
 525 static off_t
 526 FcCacheSkipToArch (int fd, const char * arch)
 527 {
 528     char candidate_arch_machine_name_count[MACHINE_SIGNATURE_SIZE + 9];
 529     char * candidate_arch;
 530     off_t current_arch_start = 0;
 531
 532     lseek (fd, 0, SEEK_SET);
 533     FcCacheSkipString (fd);
 534     current_arch_start = lseek (fd, 0, SEEK_CUR);
 535
 536     /* skip arches that are not the current arch */
 537     while (1)
 538     {
 539         long bs;
 540
 541         if (lseek (fd, current_arch_start, SEEK_SET) != current_arch_start)
 542             return -1;
 543
 544         if (FcCacheReadString (fd, candidate_arch_machine_name_count,
 545                                 sizeof (candidate_arch_machine_name_count)) == 0)
 546             return -1;
 547         if (!strlen(candidate_arch_machine_name_count))
 548             return -1;
 549         bs = strtol(candidate_arch_machine_name_count, &candidate_arch, 16);
 550
 551         // count = 0 should probably be distinguished from the !bs condition
 552         if (!bs || bs < strlen (candidate_arch_machine_name_count))
 553             return -1;
 554
 555         candidate_arch++; /* skip leading space */
 556
 557         if (strcmp (candidate_arch, arch)==0)
 558             return current_arch_start;
 559         current_arch_start += bs;
 560     }
 561
 562     return -1;
 563 }
 564
 565 /* Cuts out the segment at the file pointer (moves everything else
 566  * down to cover it), and leaves the file pointer at the end of the
 567  * file. */
 568 static FcBool
 569 FcCacheCopyOld (int fd, int fd_orig, off_t start)
 570 {
 571     char * buf = malloc (8192);
 572     char candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 573     long bs;
 574     int c, bytes_skipped;
 575     off_t loc;
 576
 577     if (!buf)
 578         return FcFalse;
 579
 580     loc = 0;
 581     lseek (fd, 0, SEEK_SET); lseek (fd_orig, 0, SEEK_SET);
 582     do
 583     {
 584         int b = 8192;
 585         if (loc + b > start)
 586             b = start - loc;
 587
 588         if ((c = read (fd_orig, buf, b)) <= 0)
 589             break;
 590         if (write (fd, buf, c) < 0)
 591             goto bail;
 592
 593         loc += c;
 594     }
 595     while (c > 0);
 596
 597     lseek (fd, start, SEEK_SET);
 598     if (FcCacheReadString (fd, candidate_arch_machine_name,
 599                            sizeof (candidate_arch_machine_name)) == 0)
 600         goto done;
 601     if (!strlen(candidate_arch_machine_name))
 602         goto done;
 603
 604     bs = strtol(candidate_arch_machine_name, 0, 16);
 605     if (bs == 0)
 606         goto done;
 607
 608     bytes_skipped = 0;
 609     do
 610     {
 611         lseek (fd, start+bs+bytes_skipped, SEEK_SET);
 612         if ((c = read (fd, buf, 8192)) <= 0)
 613             break;
 614         lseek (fd, start+bytes_skipped, SEEK_SET);
 615         if (write (fd, buf, c) < 0)
 616             goto bail;
 617         bytes_skipped += c;
 618     }
 619     while (c > 0);
 620     lseek (fd, start+bytes_skipped, SEEK_SET);
 621
 622  done:
 623     free (buf);
 624     return FcTrue;
 625
 626  bail:
 627     free (buf);
 628     return FcFalse;
 629 }
 630
 631 /* Does not check that the cache has the appropriate arch section. */
 632 /* Also, this can be fooled if the original location has a stale
 633  * cache, and the hashed location has an up-to-date cache.  Oh well,
 634  * sucks to be you in that case! */
 635 FcBool
 636 FcDirCacheValid (const FcChar8 *dir)
 637 {
 638     struct stat file_stat, dir_stat;
 639     int         fd;
 640
 641     if (stat ((char *) dir, &dir_stat) < 0)
 642         return FcFalse;
 643
 644     fd = FcDirCacheOpen (dir);
 645
 646     if (fd < 0)
 647         goto bail;
 648     if (fstat (fd, &file_stat) < 0)
 649         goto bail;
 650
 651     close (fd);
 652
 653     /*
 654      * If the directory has been modified more recently than
 655      * the cache file, the cache is not valid
 656      */
 657     if (dir_stat.st_mtime > file_stat.st_mtime)
 658         return FcFalse;
 659
 660     return FcTrue;
 661
 662  bail:
 663     close (fd);
 664     return FcFalse;
 665 }
 666
 667 /* Assumes that the cache file in 'dir' exists.
 668  * Checks that the cache has the appropriate arch section. */
 669 FcBool
 670 FcDirCacheHasCurrentArch (const FcChar8 *dir)
 671 {
 672     int         fd;
 673     off_t       current_arch_start;
 674     char        *current_arch_machine_name;
 675
 676     fd = FcDirCacheOpen (dir);
 677     if (fd < 0)
 678         goto bail;
 679
 680     current_arch_machine_name = FcCacheMachineSignature();
 681     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 682     close (fd);
 683
 684     if (current_arch_start < 0)
 685         return FcFalse;
 686
 687     return FcTrue;
 688
 689  bail:
 690     return FcFalse;
 691 }
 692
 693 FcBool
 694 FcDirCacheUnlink (const FcChar8 *dir, FcConfig *config)
 695 {
 696     char        *cache_file;
 697     char        *cache_hashed = 0;
 698     int         fd, collisions;
 699     struct stat cache_stat;
 700     char        name_buf[FC_MAX_FILE_LEN];
 701
 702     dir = FcConfigNormalizeFontDir (config, dir);
 703     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 704     if (!cache_file)
 705         return FcFalse;
 706
 707     /* First remove normal cache file. */
 708     if (stat ((char *) cache_file, &cache_stat) == 0 &&
 709         unlink ((char *)cache_file) != 0)
 710         goto bail;
 711
 712     /* Next remove any applicable hashed files. */
 713     fd = -1; collisions = 0;
 714     do
 715     {
 716         if (cache_hashed)
 717             FcStrFree ((FcChar8 *)cache_hashed);
 718
 719         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
 720         if (!cache_hashed)
 721             goto bail;
 722
 723         if (fd > 0)
 724             close (fd);
 725         fd = open(cache_hashed, O_RDONLY);
 726         if (fd == -1)
 727         {
 728             FcStrFree ((FcChar8 *)cache_file);
 729             return FcTrue;
 730         }
 731
 732         if (!FcCacheReadString (fd, name_buf, sizeof (name_buf)) || !strlen(name_buf))
 733         {
 734             FcStrFree ((FcChar8 *)cache_hashed);
 735             goto bail;
 736         }
 737     } while (strcmp (name_buf, cache_file) != 0);
 738
 739     FcStrFree ((FcChar8 *)cache_file);
 740     close (fd);
 741
 742     if (stat ((char *) cache_hashed, &cache_stat) == 0 &&
 743         unlink ((char *)cache_hashed) != 0)
 744     {
 745         FcStrFree ((FcChar8 *)cache_hashed);
 746         goto bail;
 747     }
 748
 749     FcStrFree ((FcChar8 *)cache_hashed);
 750     return FcTrue;
 751
 752  bail:
 753     FcStrFree ((FcChar8 *)cache_file);
 754     return FcFalse;
 755 }
 756
 757 static int
 758 FcCacheReadDirs (FcConfig * config, FcGlobalCache * cache,
 759                  FcStrList *list, FcFontSet * set)
 760 {
 761     int                 ret = 0;
 762     FcChar8             *dir;
 763     FcChar8             *file, *base;
 764     FcStrSet            *subdirs;
 765     FcStrList           *sublist;
 766     struct stat         statb;
 767
 768     /*
 769      * Read in the results from 'list'.
 770      */
 771     while ((dir = FcStrListNext (list)))
 772     {
 773         if (!FcConfigAcceptFilename (config, dir))
 774             continue;
 775
 776         /* freed below */
 777         file = (FcChar8 *) malloc (strlen ((char *) dir) + 1 + FC_MAX_FILE_LEN + 1);
 778         if (!file)
 779             return FcFalse;
 780
 781         strcpy ((char *) file, (char *) dir);
 782         strcat ((char *) file, "/");
 783         base = file + strlen ((char *) file);
 784
 785         subdirs = FcStrSetCreate ();
 786         if (!subdirs)
 787         {
 788             fprintf (stderr, "Can't create directory set\n");
 789             ret++;
 790             free (file);
 791             continue;
 792         }
 793
 794         if (access ((char *) dir, X_OK) < 0)
 795         {
 796             switch (errno) {
 797             case ENOENT:
 798             case ENOTDIR:
 799             case EACCES:
 800                 break;
 801             default:
 802                 fprintf (stderr, "\"%s\": ", dir);
 803                 perror ("");
 804                 ret++;
 805             }
 806             FcStrSetDestroy (subdirs);
 807             free (file);
 808             continue;
 809         }
 810         if (stat ((char *) dir, &statb) == -1)
 811         {
 812             fprintf (stderr, "\"%s\": ", dir);
 813             perror ("");
 814             FcStrSetDestroy (subdirs);
 815             ret++;
 816             free (file);
 817             continue;
 818         }
 819         if (!S_ISDIR (statb.st_mode))
 820         {
 821             fprintf (stderr, "\"%s\": not a directory, skipping\n", dir);
 822             FcStrSetDestroy (subdirs);
 823             free (file);
 824             continue;
 825         }
 826         if (!FcDirCacheValid (dir) || !FcDirCacheRead (set, subdirs, dir, config))
 827         {
 828             if (FcDebug () & FC_DBG_FONTSET)
 829                 printf ("cache scan dir %s\n", dir);
 830
 831             FcDirScanConfig (set, subdirs, cache,
 832                              config->blanks, dir, FcFalse, config);
 833         }
 834         sublist = FcStrListCreate (subdirs);
 835         FcStrSetDestroy (subdirs);
 836         if (!sublist)
 837         {
 838             fprintf (stderr, "Can't create subdir list in \"%s\"\n", dir);
 839             ret++;
 840             free (file);
 841             continue;
 842         }
 843         ret += FcCacheReadDirs (config, cache, sublist, set);
 844         free (file);
 845     }
 846     FcStrListDone (list);
 847     return ret;
 848 }
 849
 850 FcFontSet *
 851 FcCacheRead (FcConfig *config, FcGlobalCache * cache)
 852 {
 853     FcFontSet * s = FcFontSetCreate();
 854     if (!s)
 855         return 0;
 856
 857     if (FcCacheReadDirs (config, cache, FcConfigGetConfigDirs (config), s))
 858         goto bail;
 859
 860     return s;
 861
 862  bail:
 863     FcFontSetDestroy (s);
 864     return 0;
 865 }
 866
 867 static const char bin2hex[] = { '0', '1', '2', '3',
 868                                 '4', '5', '6', '7',
 869                                 '8', '9', 'a', 'b',
 870                                 'c', 'd', 'e', 'f' };
 871
 872 static char *
 873 FcDirCacheHashName (char * cache_file, int collisions)
 874 {
 875     unsigned char       hash[16], hex_hash[33];
 876     char                *cache_hashed;
 877     unsigned char       uscore = '_';
 878     int                 cnt, i;
 879     FcChar8             *tmp;
 880     struct MD5Context   ctx;
 881
 882     MD5Init (&ctx);
 883     MD5Update (&ctx, (unsigned char *)cache_file, strlen (cache_file));
 884
 885     for (i = 0; i < collisions; i++)
 886         MD5Update (&ctx, &uscore, 1);
 887
 888     MD5Final (hash, &ctx);
 889
 890     for (cnt = 0; cnt < 16; ++cnt)
 891     {
 892         hex_hash[2*cnt] = bin2hex[hash[cnt] >> 4];
 893         hex_hash[2*cnt+1] = bin2hex[hash[cnt] & 0xf];
 894     }
 895     hex_hash[32] = 0;
 896
 897     tmp = FcStrPlus ((FcChar8 *)hex_hash, (FcChar8 *)FC_CACHE_SUFFIX);
 898     if (!tmp)
 899         return 0;
 900
 901     cache_hashed = (char *)FcStrPlus ((FcChar8 *)PKGCACHEDIR"/", tmp);
 902     free (tmp);
 903
 904     return cache_hashed;
 905 }
 906
 907 /* Opens the hashed name for cache_file.
 908  * This would fail in the unlikely event of a collision and subsequent
 909  * removal of the file which originally caused the collision. */
 910 static int
 911 FcDirCacheOpen (const FcChar8 *dir)
 912 {
 913     FcBool      found;
 914     int         fd = -1, collisions = 0;
 915     char        *cache_file, *cache_hashed;
 916     char        name_buf[FC_MAX_FILE_LEN];
 917     struct stat dir_stat;
 918
 919     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 920     if (!cache_file)
 921         return -1;
 922
 923     fd = open(cache_file, O_RDONLY);
 924     if (fd != -1)
 925         return fd;
 926
 927     if (stat ((char *)dir, &dir_stat) == -1)
 928         return -1;
 929
 930     found = FcFalse;
 931     do
 932     {
 933         struct stat c;
 934         FcChar8 * name_buf_dir;
 935
 936         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
 937         if (!cache_hashed)
 938         {
 939             FcStrFree ((FcChar8 *)cache_file);
 940             return -1;
 941         }
 942
 943         if (fd > 0)
 944             close (fd);
 945         fd = open(cache_hashed, O_RDONLY);
 946         FcStrFree ((FcChar8 *)cache_hashed);
 947
 948         if (fd == -1)
 949         {
 950             FcStrFree ((FcChar8 *)cache_file);
 951             return -1;
 952         }
 953         if (!FcCacheReadString (fd, name_buf, sizeof (name_buf)) || !strlen(name_buf))
 954             goto bail;
 955
 956         name_buf_dir = FcStrDirname ((FcChar8 *)name_buf);
 957         if (stat ((char *)name_buf_dir, &c) == -1)
 958         {
 959             FcStrFree (name_buf_dir);
 960             continue;
 961         }
 962         FcStrFree (name_buf_dir);
 963         found = (c.st_ino == dir_stat.st_ino) && (c.st_dev == dir_stat.st_dev);
 964     } while (!found);
 965     FcStrFree ((FcChar8 *)cache_file);
 966     return fd;
 967
 968  bail:
 969     FcStrFree ((FcChar8 *)cache_file);
 970     close (fd);
 971     return -1;
 972 }
 973
 974 /* read serialized state from the cache file */
 975 FcBool
 976 FcDirCacheRead (FcFontSet * set, FcStrSet * dirs, const FcChar8 *dir, FcConfig *config)
 977 {
 978     int         fd;
 979     char        *current_arch_machine_name;
 980     char        candidate_arch_machine_name[9+MACHINE_SIGNATURE_SIZE];
 981     off_t       current_arch_start = 0;
 982     char        subdirName[FC_MAX_FILE_LEN + 1 + 12 + 1];
 983
 984     fd = FcDirCacheOpen (dir);
 985     if (fd < 0)
 986         goto bail;
 987
 988     current_arch_machine_name = FcCacheMachineSignature();
 989     current_arch_start = FcCacheSkipToArch(fd,
 990                                            current_arch_machine_name);
 991     if (current_arch_start < 0)
 992         goto bail1;
 993
 994     lseek (fd, current_arch_start, SEEK_SET);
 995     if (FcCacheReadString (fd, candidate_arch_machine_name,
 996                            sizeof (candidate_arch_machine_name)) == 0)
 997         goto bail1;
 998
 999     while (FcCacheReadString (fd, subdirName, sizeof (subdirName)) && strlen (subdirName) > 0)
1000         FcStrSetAdd (dirs, (FcChar8 *)subdirName);
1001
1002     if (!FcDirCacheConsume (fd, (const char *)dir, set, config))
1003         goto bail1;
1004
1005     close(fd);
1006     return FcTrue;
1007
1008  bail1:
1009     close (fd);
1010  bail:
1011     return FcFalse;
1012 }
1013
1014 static FcBool
1015 FcDirCacheConsume (int fd, const char * dir, FcFontSet *set, FcConfig *config)
1016 {
1017     FcCache metadata;
1018     void * current_dir_block;
1019     off_t pos;
1020
1021     read(fd, &metadata, sizeof(FcCache));
1022     if (metadata.magic != FC_CACHE_MAGIC)
1023         return FcFalse;
1024
1025     if (!metadata.count)
1026     {
1027         pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
1028         lseek (fd, pos, SEEK_SET);
1029         if (config)
1030             FcConfigAddFontDir (config, (FcChar8 *)dir);
1031         return FcTrue;
1032     }
1033
1034     pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
1035     current_dir_block = mmap (0, metadata.count,
1036                               PROT_READ, MAP_SHARED, fd, pos);
1037     lseek (fd, pos+metadata.count, SEEK_SET);
1038     if (current_dir_block == MAP_FAILED)
1039         return FcFalse;
1040
1041     FcCacheAddBankDir (metadata.bank, dir);
1042     if (config)
1043         FcConfigAddFontDir (config, (FcChar8 *)dir);
1044
1045     if (!FcFontSetUnserialize (&metadata, set, current_dir_block))
1046         return FcFalse;
1047
1048     return FcTrue;
1049 }
1050
1051 static void *
1052 FcDirCacheProduce (FcFontSet *set, FcCache *metadata)
1053 {
1054     void * current_dir_block, * final_dir_block;
1055     static unsigned int rand_state = 0;
1056     int bank, needed_bytes_no_align;
1057
1058     if (!rand_state)
1059         rand_state = time(0L);
1060     bank = rand_r(&rand_state);
1061
1062     while (FcCacheHaveBank(bank))
1063         bank = rand_r(&rand_state);
1064
1065     memset (metadata, 0, sizeof(FcCache));
1066     FcFontSetNewBank();
1067     needed_bytes_no_align = FcFontSetNeededBytes (set);
1068     metadata->count = needed_bytes_no_align +
1069         FcFontSetNeededBytesAlign ();
1070     metadata->magic = FC_CACHE_MAGIC;
1071     metadata->bank = bank;
1072
1073     if (!needed_bytes_no_align) /* not a failure, no fonts to write */
1074     {
1075         /* no, you don't really need to write any bytes at all. */
1076         metadata->count = 0;
1077         return 0;
1078     }
1079
1080     current_dir_block = malloc (metadata->count);
1081     if (!current_dir_block)
1082         goto bail;
1083     // shut up valgrind
1084     memset (current_dir_block, 0, metadata->count);
1085     final_dir_block = FcFontSetDistributeBytes (metadata, current_dir_block);
1086
1087     if ((void *)((char *)current_dir_block+metadata->count) < final_dir_block)
1088         goto bail;
1089
1090     if (!FcFontSetSerialize (bank, set))
1091         goto bail;
1092
1093     return current_dir_block;
1094
1095  bail:
1096     free (current_dir_block);
1097     return 0;
1098 }
1099
1100 /* write serialized state to the cache file */
1101 FcBool
1102 FcDirCacheWrite (FcFontSet *set, FcStrSet *dirs, const FcChar8 *dir)
1103 {
1104     char            *cache_file;
1105     char            *cache_hashed;
1106     int             fd, fd_orig, i, dirs_count;
1107     FcAtomic        *atomic;
1108     FcCache         metadata;
1109     off_t           current_arch_start = 0, truncate_to;
1110     char            name_buf[FC_MAX_FILE_LEN];
1111     int             collisions;
1112
1113     char            *current_arch_machine_name, * header;
1114     void            *current_dir_block = 0;
1115
1116     dir = FcConfigNormalizeFontDir (FcConfigGetCurrent(), dir);
1117     if (!dir)
1118         return FcFalse;
1119
1120     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
1121     if (!cache_file)
1122         goto bail;
1123
1124     /* Ensure that we're not trampling a cache for some other dir. */
1125     /* This is slightly different from FcDirCacheOpen, since it
1126      * needs the filename, not the file descriptor. */
1127     fd = -1; collisions = 0;
1128     do
1129     {
1130         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
1131         if (!cache_hashed)
1132             goto bail0;
1133
1134         if (fd > 0)
1135             close (fd);
1136         fd = open(cache_hashed, O_RDONLY);
1137         if (fd == -1)
1138             break;
1139         if(!FcCacheReadString (fd, name_buf, sizeof (name_buf)) || !strlen(name_buf))
1140         {
1141             close (fd);
1142             break;
1143         }
1144         close (fd);
1145
1146         if (strcmp (name_buf, cache_file) != 0)
1147             continue;
1148     } while (0);
1149
1150     current_dir_block = FcDirCacheProduce (set, &metadata);
1151
1152     if (metadata.count && !current_dir_block)
1153         goto bail1;
1154
1155     if (FcDebug () & FC_DBG_CACHE)
1156         printf ("FcDirCacheWriteDir cache_file \"%s\"\n", cache_file);
1157
1158     atomic = FcAtomicCreate ((FcChar8 *)cache_hashed);
1159     if (!atomic)
1160         goto bail1;
1161
1162     if (!FcAtomicLock (atomic))
1163     {
1164         /* Now try rewriting the original version of the file. */
1165         FcAtomicDestroy (atomic);
1166
1167         atomic = FcAtomicCreate ((FcChar8 *)cache_file);
1168         fd_orig = open (cache_file, O_RDONLY);
1169         if (fd_orig == -1)
1170             fd_orig = open((char *)FcAtomicOrigFile (atomic), O_RDONLY);
1171
1172         fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT, 0666);
1173         if (fd == -1)
1174             goto bail2;
1175     }
1176
1177     /* In all cases, try opening the real location of the cache file first. */
1178     /* (even if that's not atomic.) */
1179     fd_orig = open (cache_file, O_RDONLY);
1180     if (fd_orig == -1)
1181         fd_orig = open((char *)FcAtomicOrigFile (atomic), O_RDONLY);
1182
1183     fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT, 0666);
1184     if (fd == -1)
1185         goto bail3;
1186
1187     FcCacheWriteString (fd, cache_file);
1188
1189     current_arch_machine_name = FcCacheMachineSignature ();
1190     current_arch_start = 0;
1191
1192     if (fd_orig != -1)
1193         current_arch_start =
1194             FcCacheSkipToArch(fd_orig, current_arch_machine_name);
1195
1196     if (current_arch_start < 0)
1197     {
1198         off_t i = lseek(fd_orig, 0, SEEK_END);
1199         if (i < strlen (FC_GLOBAL_MAGIC_COOKIE)+1)
1200             i = strlen (FC_GLOBAL_MAGIC_COOKIE)+1;
1201         current_arch_start = FcCacheNextOffset (i);
1202     }
1203
1204     if (fd_orig != -1 && !FcCacheCopyOld(fd, fd_orig, current_arch_start))
1205         goto bail4;
1206
1207     if (fd_orig != -1)
1208         close (fd_orig);
1209
1210     current_arch_start = lseek(fd, 0, SEEK_CUR);
1211     if (ftruncate (fd, current_arch_start) == -1)
1212         goto bail4;
1213
1214     /* allocate space for subdir names in this block */
1215     dirs_count = 0;
1216     for (i = 0; i < dirs->size; i++)
1217         dirs_count += strlen((char *)dirs->strs[i]) + 1;
1218     dirs_count ++;
1219
1220     /* now write the address of the next offset */
1221     truncate_to = FcCacheNextOffset (FcCacheNextOffset (current_arch_start + sizeof (FcCache) + dirs_count) + metadata.count) - current_arch_start;
1222     header = malloc (10 + strlen (current_arch_machine_name));
1223     if (!header)
1224         goto bail4;
1225     sprintf (header, "%8x ", (int)truncate_to);
1226     strcat (header, current_arch_machine_name);
1227     if (!FcCacheWriteString (fd, header))
1228         goto bail5;
1229
1230     for (i = 0; i < dirs->size; i++)
1231         FcCacheWriteString (fd, (char *)dirs->strs[i]);
1232     FcCacheWriteString (fd, "");
1233
1234     write (fd, &metadata, sizeof(FcCache));
1235     if (metadata.count)
1236     {
1237         lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_END)), SEEK_SET);
1238         write (fd, current_dir_block, metadata.count);
1239         free (current_dir_block);
1240     }
1241
1242     /* this actually serves to pad out the cache file, if needed */
1243     if (ftruncate (fd, current_arch_start + truncate_to) == -1)
1244         goto bail5;
1245
1246     free (header);
1247     close(fd);
1248     if (!FcAtomicReplaceOrig(atomic))
1249         goto bail5;
1250     FcStrFree ((FcChar8 *)cache_hashed);
1251     FcStrFree ((FcChar8 *)cache_file);
1252     FcAtomicUnlock (atomic);
1253     FcAtomicDestroy (atomic);
1254     return FcTrue;
1255
1256  bail5:
1257     free (header);
1258  bail4:
1259     close (fd);
1260  bail3:
1261     FcAtomicUnlock (atomic);
1262  bail2:
1263     FcAtomicDestroy (atomic);
1264  bail1:
1265     FcStrFree ((FcChar8 *)cache_hashed);
1266  bail0:
1267     unlink ((char *)cache_file);
1268     FcStrFree ((FcChar8 *)cache_file);
1269     if (current_dir_block)
1270         free (current_dir_block);
1271  bail:
1272     return FcFalse;
1273 }
1274
1275 static char *
1276 FcCacheMachineSignature ()
1277 {
1278     static char buf[MACHINE_SIGNATURE_SIZE];
1279     int32_t magic = ENDIAN_TEST;
1280     char * m = (char *)&magic;
1281
1282     sprintf (buf, "%2x%2x%2x%2x "
1283              "%4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x "
1284              "%4x %4x %4x %4x %4x %4x %4x %4x\n",
1285              m[0], m[1], m[2], m[3],
1286              (unsigned int)sizeof (char),
1287              (unsigned int)sizeof (char *),
1288              (unsigned int)sizeof (int),
1289              (unsigned int)sizeof (FcPattern),
1290              (unsigned int)sizeof (FcPatternEltPtr),
1291              (unsigned int)sizeof (struct _FcPatternElt *),
1292              (unsigned int)sizeof (FcPatternElt),
1293              (unsigned int)sizeof (FcObjectPtr),
1294              (unsigned int)sizeof (FcValueListPtr),
1295              (unsigned int)sizeof (FcValue),
1296              (unsigned int)sizeof (FcValueBinding),
1297              (unsigned int)sizeof (struct _FcValueList *),
1298              (unsigned int)sizeof (FcCharSet),
1299              (unsigned int)sizeof (FcCharLeaf **),
1300              (unsigned int)sizeof (FcChar16 *),
1301              (unsigned int)sizeof (FcChar16),
1302              (unsigned int)sizeof (FcCharLeaf),
1303              (unsigned int)sizeof (FcChar32),
1304              (unsigned int)sizeof (FcCache),
1305              (unsigned int)sysconf(_SC_PAGESIZE));
1306
1307     return buf;
1308 }
1309
1310 static int banks_ptr = 0, banks_alloc = 0;
1311 int * _fcBankId = 0, * _fcBankIdx = 0;
1312 static const char ** bankDirs = 0;
1313
1314 static FcBool
1315 FcCacheHaveBank (int bank)
1316 {
1317     int i;
1318
1319     if (bank < FC_BANK_FIRST)
1320         return FcTrue;
1321
1322     for (i = 0; i < banks_ptr; i++)
1323         if (_fcBankId[i] == bank)
1324             return FcTrue;
1325
1326     return FcFalse;
1327 }
1328
1329 int
1330 FcCacheBankToIndexMTF (int bank)
1331 {
1332     int i, j;
1333
1334     for (i = 0; i < banks_ptr; i++)
1335         if (_fcBankId[_fcBankIdx[i]] == bank)
1336         {
1337             int t = _fcBankIdx[i];
1338
1339             for (j = i; j > 0; j--)
1340                 _fcBankIdx[j] = _fcBankIdx[j-1];
1341             _fcBankIdx[0] = t;
1342             return t;
1343         }
1344
1345     if (banks_ptr >= banks_alloc)
1346     {
1347         int * b, * bidx;
1348         const char ** bds;
1349
1350         b = realloc (_fcBankId, (banks_alloc + 4) * sizeof(int));
1351         if (!b)
1352             return -1;
1353         _fcBankId = b;
1354
1355         bidx = realloc (_fcBankIdx, (banks_alloc + 4) * sizeof(int));
1356         if (!bidx)
1357             return -1;
1358         _fcBankIdx = bidx;
1359
1360         bds = realloc (bankDirs, (banks_alloc + 4) * sizeof (char *));
1361         if (!bds)
1362             return -1;
1363         bankDirs = bds;
1364
1365         banks_alloc += 4;
1366     }
1367
1368     i = banks_ptr++;
1369     _fcBankId[i] = bank;
1370     _fcBankIdx[i] = i;
1371     return i;
1372 }
1373
1374 static void
1375 FcCacheAddBankDir (int bank, const char * dir)
1376 {
1377     int bi = FcCacheBankToIndexMTF (bank);
1378
1379     if (bi < 0)
1380         return;
1381
1382     bankDirs[bi] = (const char *)FcStrCopy ((FcChar8 *)dir);
1383 }
1384
1385 const char *
1386 FcCacheFindBankDir (int bank)
1387 {
1388     int bi = FcCacheBankToIndex (bank);
1389     return bankDirs[bi];
1390 }
1391
1392 /*
1393  * This code implements the MD5 message-digest algorithm.
1394  * The algorithm is due to Ron Rivest.  This code was
1395  * written by Colin Plumb in 1993, no copyright is claimed.
1396  * This code is in the public domain; do with it what you wish.
1397  *
1398  * Equivalent code is available from RSA Data Security, Inc.
1399  * This code has been tested against that, and is equivalent,
1400  * except that you don't need to include two pages of legalese
1401  * with every copy.
1402  *
1403  * To compute the message digest of a chunk of bytes, declare an
1404  * MD5Context structure, pass it to MD5Init, call MD5Update as
1405  * needed on buffers full of bytes, and then call MD5Final, which
1406  * will fill a supplied 16-byte array with the digest.
1407  */
1408
1409 #ifndef HIGHFIRST
1410 #define byteReverse(buf, len)   /* Nothing */
1411 #else
1412 /*
1413  * Note: this code is harmless on little-endian machines.
1414  */
1415 void byteReverse(unsigned char *buf, unsigned longs)
1416 {
1417     FcChar32 t;
1418     do {
1419         t = (FcChar32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
1420             ((unsigned) buf[1] << 8 | buf[0]);
1421         *(FcChar32 *) buf = t;
1422         buf += 4;
1423     } while (--longs);
1424 }
1425 #endif
1426
1427 /*
1428  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
1429  * initialization constants.
1430  */
1431 static void MD5Init(struct MD5Context *ctx)
1432 {
1433     ctx->buf[0] = 0x67452301;
1434     ctx->buf[1] = 0xefcdab89;
1435     ctx->buf[2] = 0x98badcfe;
1436     ctx->buf[3] = 0x10325476;
1437
1438     ctx->bits[0] = 0;
1439     ctx->bits[1] = 0;
1440 }
1441
1442 /*
1443  * Update context to reflect the concatenation of another buffer full
1444  * of bytes.
1445  */
1446 static void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len)
1447 {
1448     FcChar32 t;
1449
1450     /* Update bitcount */
1451
1452     t = ctx->bits[0];
1453     if ((ctx->bits[0] = t + ((FcChar32) len << 3)) < t)
1454         ctx->bits[1]++;         /* Carry from low to high */
1455     ctx->bits[1] += len >> 29;
1456
1457     t = (t >> 3) & 0x3f;        /* Bytes already in shsInfo->data */
1458
1459     /* Handle any leading odd-sized chunks */
1460
1461     if (t) {
1462         unsigned char *p = (unsigned char *) ctx->in + t;
1463
1464         t = 64 - t;
1465         if (len < t) {
1466             memcpy(p, buf, len);
1467             return;
1468         }
1469         memcpy(p, buf, t);
1470         byteReverse(ctx->in, 16);
1471         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1472         buf += t;
1473         len -= t;
1474     }
1475     /* Process data in 64-byte chunks */
1476
1477     while (len >= 64) {
1478         memcpy(ctx->in, buf, 64);
1479         byteReverse(ctx->in, 16);
1480         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1481         buf += 64;
1482         len -= 64;
1483     }
1484
1485     /* Handle any remaining bytes of data. */
1486
1487     memcpy(ctx->in, buf, len);
1488 }
1489
1490 /*
1491  * Final wrapup - pad to 64-byte boundary with the bit pattern
1492  * 1 0* (64-bit count of bits processed, MSB-first)
1493  */
1494 static void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
1495 {
1496     unsigned count;
1497     unsigned char *p;
1498
1499     /* Compute number of bytes mod 64 */
1500     count = (ctx->bits[0] >> 3) & 0x3F;
1501
1502     /* Set the first char of padding to 0x80.  This is safe since there is
1503        always at least one byte free */
1504     p = ctx->in + count;
1505     *p++ = 0x80;
1506
1507     /* Bytes of padding needed to make 64 bytes */
1508     count = 64 - 1 - count;
1509
1510     /* Pad out to 56 mod 64 */
1511     if (count < 8) {
1512         /* Two lots of padding:  Pad the first block to 64 bytes */
1513         memset(p, 0, count);
1514         byteReverse(ctx->in, 16);
1515         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1516
1517         /* Now fill the next block with 56 bytes */
1518         memset(ctx->in, 0, 56);
1519     } else {
1520         /* Pad block to 56 bytes */
1521         memset(p, 0, count - 8);
1522     }
1523     byteReverse(ctx->in, 14);
1524
1525     /* Append length in bits and transform */
1526     ((FcChar32 *) ctx->in)[14] = ctx->bits[0];
1527     ((FcChar32 *) ctx->in)[15] = ctx->bits[1];
1528
1529     MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1530     byteReverse((unsigned char *) ctx->buf, 4);
1531     memcpy(digest, ctx->buf, 16);
1532     memset(ctx, 0, sizeof(ctx));        /* In case it's sensitive */
1533 }
1534
1535
1536 /* The four core functions - F1 is optimized somewhat */
1537
1538 /* #define F1(x, y, z) (x & y | ~x & z) */
1539 #define F1(x, y, z) (z ^ (x & (y ^ z)))
1540 #define F2(x, y, z) F1(z, x, y)
1541 #define F3(x, y, z) (x ^ y ^ z)
1542 #define F4(x, y, z) (y ^ (x | ~z))
1543
1544 /* This is the central step in the MD5 algorithm. */
1545 #define MD5STEP(f, w, x, y, z, data, s) \
1546         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
1547
1548 /*
1549  * The core of the MD5 algorithm, this alters an existing MD5 hash to
1550  * reflect the addition of 16 longwords of new data.  MD5Update blocks
1551  * the data and converts bytes into longwords for this routine.
1552  */
1553 static void MD5Transform(FcChar32 buf[4], FcChar32 in[16])
1554 {
1555     register FcChar32 a, b, c, d;
1556
1557     a = buf[0];
1558     b = buf[1];
1559     c = buf[2];
1560     d = buf[3];
1561
1562     MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
1563     MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
1564     MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
1565     MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
1566     MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
1567     MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
1568     MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
1569     MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
1570     MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
1571     MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
1572     MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
1573     MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
1574     MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
1575     MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
1576     MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
1577     MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
1578
1579     MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
1580     MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
1581     MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
1582     MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
1583     MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
1584     MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
1585     MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
1586     MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
1587     MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
1588     MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
1589     MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
1590     MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
1591     MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
1592     MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
1593     MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
1594     MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
1595
1596     MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
1597     MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
1598     MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
1599     MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
1600     MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
1601     MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
1602     MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
1603     MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
1604     MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
1605     MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
1606     MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
1607     MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
1608     MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
1609     MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
1610     MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
1611     MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
1612
1613     MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
1614     MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
1615     MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
1616     MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
1617     MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
1618     MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
1619     MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
1620     MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
1621     MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
1622     MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
1623     MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
1624     MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
1625     MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
1626     MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
1627     MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
1628     MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
1629
1630     buf[0] += a;
1631     buf[1] += b;
1632     buf[2] += c;
1633     buf[3] += d;
1634 }