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