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