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