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