src/fccache.c

   1 /*
   2  * $RCSId: xc/lib/fontconfig/src/fccache.c,v 1.12 2002/08/22 07:36:44 keithp Exp $
   3  *
   4  * Copyright © 2000 Keith Packard
   5  * Copyright © 2005 Patrick Lam
   6  *
   7  * Permission to use, copy, modify, distribute, and sell this software and its
   8  * documentation for any purpose is hereby granted without fee, provided that
   9  * the above copyright notice appear in all copies and that both that
  10  * copyright notice and this permission notice appear in supporting
  11  * documentation, and that the name of Keith Packard not be used in
  12  * advertising or publicity pertaining to distribution of the software without
  13  * specific, written prior permission.  Keith Packard makes no
  14  * representations about the suitability of this software for any purpose.  It
  15  * is provided "as is" without express or implied warranty.
  16  *
  17  * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  18  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  19  * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  20  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  21  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  22  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  23  * PERFORMANCE OF THIS SOFTWARE.
  24  */
  25
  26 #include <fcntl.h>
  27 #include <dirent.h>
  28 #include <string.h>
  29 #include <sys/mman.h>
  30 #include <sys/utsname.h>
  31 #include <sys/types.h>
  32 #include <unistd.h>
  33 #include "fcint.h"
  34 #include <unistd.h>
  35
  36 #define ENDIAN_TEST 0x12345678
  37 #define MACHINE_SIGNATURE_SIZE 9 + 5*20 + 1
  38
  39 static int
  40 FcDirCacheOpen (const FcChar8 * dir);
  41
  42 static char *
  43 FcDirCacheHashName (char * cache_file, int collisions);
  44
  45 static off_t
  46 FcCacheSkipToArch (int fd, const char * arch);
  47
  48 static FcBool
  49 FcCacheCopyOld (int fd, int fd_orig, off_t start);
  50
  51 static void *
  52 FcDirCacheProduce (FcFontSet *set, FcCache * metadata);
  53
  54 static FcBool
  55 FcDirCacheConsume (int fd, const char * dir, FcFontSet *set, FcConfig *config);
  56
  57 static int
  58 FcCacheNextOffset(off_t w);
  59
  60 static char *
  61 FcCacheMachineSignature (void);
  62
  63 static FcBool
  64 FcCacheHaveBank (int bank);
  65
  66 static void
  67 FcCacheAddBankDir (int bank, const char * dir);
  68
  69 struct MD5Context {
  70         FcChar32 buf[4];
  71         FcChar32 bits[2];
  72         unsigned char in[64];
  73 };
  74
  75 static void MD5Init(struct MD5Context *ctx);
  76 static void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len);
  77 static void MD5Final(unsigned char digest[16], struct MD5Context *ctx);
  78 static void MD5Transform(FcChar32 buf[4], FcChar32 in[16]);
  79
  80 #define FC_DBG_CACHE_REF    1024
  81
  82 static char *
  83 FcCacheReadString (int fd, char *dest, int len)
  84 {
  85     FcChar8     c;
  86     FcBool      escape;
  87     int         size;
  88     int         i;
  89
  90     if (len == 0)
  91         return 0;
  92
  93     size = len;
  94     i = 0;
  95     escape = FcFalse;
  96     while (read (fd, &c, 1) == 1)
  97     {
  98         if (!escape)
  99         {
 100             switch (c) {
 101             case '"':
 102                 c = '\0';
 103                 break;
 104             case '\\':
 105                 escape = FcTrue;
 106                 continue;
 107             }
 108         }
 109         if (i == size)
 110         {
 111             dest[i++] = 0;
 112             return dest;
 113         }
 114         dest[i++] = c;
 115         if (c == '\0')
 116             return dest;
 117         escape = FcFalse;
 118     }
 119     return 0;
 120 }
 121
 122 static void
 123 FcCacheSkipString (int fd)
 124 {
 125     FcChar8     c;
 126     FcBool      escape;
 127
 128     escape = FcFalse;
 129     while (read (fd, &c, 1) == 1)
 130     {
 131         if (!escape)
 132         {
 133             switch (c) {
 134             case '"':
 135                 c = '\0';
 136                 break;
 137             case '\\':
 138                 escape = FcTrue;
 139                 continue;
 140             }
 141         }
 142         if (c == '\0')
 143             return;
 144         escape = FcFalse;
 145     }
 146     return;
 147 }
 148
 149 static FcBool
 150 FcCacheWriteString (int fd, const char *chars)
 151 {
 152     if (write (fd, chars, strlen(chars)+1) != strlen(chars)+1)
 153         return FcFalse;
 154     return FcTrue;
 155 }
 156
 157 static void
 158 FcGlobalCacheDirDestroy (FcGlobalCacheDir *d)
 159 {
 160     FcMemFree (FC_MEM_STRING, strlen (d->name)+1);
 161     free (d->name);
 162     FcMemFree (FC_MEM_CACHE, sizeof (FcGlobalCacheDir));
 163     free (d);
 164 }
 165
 166 FcGlobalCache *
 167 FcGlobalCacheCreate (void)
 168 {
 169     FcGlobalCache   *cache;
 170
 171     cache = malloc (sizeof (FcGlobalCache));
 172     if (!cache)
 173         return 0;
 174     FcMemAlloc (FC_MEM_CACHE, sizeof (FcGlobalCache));
 175     cache->dirs = 0;
 176     cache->updated = FcFalse;
 177     cache->fd = -1;
 178     return cache;
 179 }
 180
 181 void
 182 FcGlobalCacheDestroy (FcGlobalCache *cache)
 183 {
 184     FcGlobalCacheDir    *d, *next;
 185
 186     for (d = cache->dirs; d; d = next)
 187     {
 188         next = d->next;
 189         FcGlobalCacheDirDestroy (d);
 190     }
 191     FcMemFree (FC_MEM_CACHE, sizeof (FcGlobalCache));
 192     free (cache);
 193 }
 194
 195 void
 196 FcGlobalCacheLoad (FcGlobalCache    *cache,
 197                    FcStrSet         *staleDirs,
 198                    const FcChar8    *cache_file,
 199                    FcConfig         *config)
 200 {
 201     char                name_buf[FC_MAX_FILE_LEN];
 202     FcGlobalCacheDir    *d, *next;
 203     FcFileTime          config_time = FcConfigModifiedTime (config);
 204     char                * current_arch_machine_name;
 205     char                candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 206     off_t               current_arch_start;
 207
 208     struct stat         cache_stat, dir_stat;
 209
 210     if (stat ((char *) cache_file, &cache_stat) < 0)
 211         return;
 212
 213     cache->fd = open ((char *) cache_file, O_RDONLY);
 214     if (cache->fd == -1)
 215         return;
 216
 217     cache->updated = FcFalse;
 218
 219     FcCacheReadString (cache->fd, name_buf, sizeof (name_buf));
 220     if (strcmp (name_buf, FC_GLOBAL_MAGIC_COOKIE) != 0)
 221         return;
 222
 223     current_arch_machine_name = FcCacheMachineSignature ();
 224     current_arch_start = FcCacheSkipToArch(cache->fd,
 225                                            current_arch_machine_name);
 226     if (current_arch_start < 0)
 227         goto bail_and_destroy;
 228
 229     lseek (cache->fd, current_arch_start, SEEK_SET);
 230     FcCacheReadString (cache->fd, candidate_arch_machine_name,
 231                        sizeof (candidate_arch_machine_name));
 232     if (strlen(candidate_arch_machine_name) == 0)
 233         goto bail_and_destroy;
 234
 235     while (1)
 236     {
 237         off_t targ;
 238
 239         FcCacheReadString (cache->fd, name_buf, sizeof (name_buf));
 240         if (!strlen(name_buf))
 241             break;
 242
 243         /* Directory must be older than the global cache file; also
 244            cache must be newer than the config file. */
 245         if (stat ((char *) name_buf, &dir_stat) < 0 ||
 246             dir_stat.st_mtime > cache_stat.st_mtime ||
 247             (config_time.set && cache_stat.st_mtime < config_time.time))
 248         {
 249             FcCache md;
 250
 251             FcStrSetAdd (staleDirs, FcStrCopy ((FcChar8 *)name_buf));
 252             read (cache->fd, &md, sizeof (FcCache));
 253             lseek (cache->fd, FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + md.count, SEEK_SET);
 254             continue;
 255         }
 256
 257         d = malloc (sizeof (FcGlobalCacheDir));
 258         if (!d)
 259             goto bail1;
 260
 261         d->next = cache->dirs;
 262         cache->dirs = d;
 263
 264         d->name = (char *)FcStrCopy ((FcChar8 *)name_buf);
 265         d->ent = 0;
 266         d->offset = lseek (cache->fd, 0, SEEK_CUR);
 267         if (read (cache->fd, &d->metadata, sizeof (FcCache)) != sizeof (FcCache))
 268             goto bail1;
 269         targ = FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + d->metadata.count;
 270         if (lseek (cache->fd, targ, SEEK_SET) != targ)
 271             goto bail1;
 272     }
 273     return;
 274
 275  bail1:
 276     for (d = cache->dirs; d; d = next)
 277     {
 278         next = d->next;
 279         free (d);
 280     }
 281     cache->dirs = 0;
 282
 283     close (cache->fd);
 284     cache->fd = -1;
 285     return;
 286
 287  bail_and_destroy:
 288     close (cache->fd);
 289     cache->fd = -1;
 290
 291     if (stat ((char *) cache_file, &cache_stat) == 0)
 292         unlink ((char *)cache_file);
 293
 294     return;
 295
 296 }
 297
 298 FcBool
 299 FcGlobalCacheReadDir (FcFontSet *set, FcStrSet *dirs, FcGlobalCache * cache, const char *dir, FcConfig *config)
 300 {
 301     FcGlobalCacheDir *d;
 302     FcBool ret = FcFalse;
 303
 304     if (cache->fd == -1)
 305         return FcFalse;
 306
 307     dir = (char *)FcConfigNormalizeFontDir (config, (FcChar8 *)dir);
 308     for (d = cache->dirs; d; d = d->next)
 309     {
 310         if (strncmp (d->name, dir, strlen(dir)) == 0)
 311         {
 312             lseek (cache->fd, d->offset, SEEK_SET);
 313             if (!FcDirCacheConsume (cache->fd, dir, set, config))
 314                 return FcFalse;
 315             if (strcmp (d->name, dir) == 0)
 316                 ret = FcTrue;
 317         }
 318     }
 319
 320     return ret;
 321 }
 322
 323 FcBool
 324 FcGlobalCacheUpdate (FcGlobalCache  *cache,
 325                      const char     *name,
 326                      FcFontSet      *set,
 327                      FcConfig       *config)
 328 {
 329     FcGlobalCacheDir * d;
 330
 331     name = (char *)FcConfigNormalizeFontDir (config, (FcChar8 *)name);
 332     for (d = cache->dirs; d; d = d->next)
 333     {
 334         if (strcmp(d->name, name) == 0)
 335             break;
 336     }
 337
 338     if (!d)
 339     {
 340         d = malloc (sizeof (FcGlobalCacheDir));
 341         if (!d)
 342             return FcFalse;
 343         d->next = cache->dirs;
 344         cache->dirs = d;
 345     }
 346
 347     cache->updated = FcTrue;
 348
 349     d->name = (char *)FcStrCopy ((FcChar8 *)name);
 350     d->ent = FcDirCacheProduce (set, &d->metadata);
 351     d->offset = 0;
 352     return FcTrue;
 353 }
 354
 355 FcBool
 356 FcGlobalCacheSave (FcGlobalCache    *cache,
 357                    const FcChar8    *cache_file,
 358                    FcConfig         *config)
 359 {
 360     int                 fd, fd_orig;
 361     FcGlobalCacheDir    *dir;
 362     FcAtomic            *atomic;
 363     off_t               current_arch_start = 0, truncate_to;
 364     char                * current_arch_machine_name, * header;
 365
 366     if (!cache->updated)
 367         return FcTrue;
 368
 369 #if defined (HAVE_GETUID) && defined (HAVE_GETEUID)
 370     /* Set-UID programs can't safely update the cache */
 371     if (getuid () != geteuid ())
 372         return FcFalse;
 373 #endif
 374
 375     atomic = FcAtomicCreate (cache_file);
 376     if (!atomic)
 377         return FcFalse;
 378
 379     if (!FcAtomicLock (atomic))
 380         goto bail1;
 381     fd = open ((char *) FcAtomicNewFile(atomic), O_RDWR | O_CREAT,
 382                S_IRUSR | S_IWUSR);
 383     if (fd == -1)
 384         goto bail2;
 385
 386     fd_orig = open ((char *) FcAtomicOrigFile(atomic), O_RDONLY);
 387
 388     current_arch_machine_name = FcCacheMachineSignature ();
 389     if (fd_orig == -1)
 390         current_arch_start = 0;
 391     else
 392         current_arch_start = FcCacheSkipToArch (fd_orig,
 393                                                 current_arch_machine_name);
 394
 395     if (current_arch_start < 0)
 396         current_arch_start = FcCacheNextOffset (lseek(fd_orig, 0, SEEK_END));
 397
 398     if (!FcCacheCopyOld(fd, fd_orig, current_arch_start))
 399         goto bail3;
 400
 401     close (fd_orig);
 402     fd_orig = -1;
 403
 404     current_arch_start = lseek(fd, 0, SEEK_CUR);
 405     if (ftruncate (fd, current_arch_start) == -1)
 406         goto bail3;
 407
 408     header = malloc (10 + strlen (current_arch_machine_name));
 409     if (!header)
 410         goto bail3;
 411
 412     truncate_to = current_arch_start + strlen(current_arch_machine_name) + 11;
 413     for (dir = cache->dirs; dir; dir = dir->next)
 414     {
 415         truncate_to += strlen(dir->name) + 1;
 416         truncate_to += sizeof (FcCache);
 417         truncate_to = FcCacheNextOffset (truncate_to);
 418         truncate_to += dir->metadata.count;
 419     }
 420     truncate_to -= current_arch_start;
 421
 422     FcCacheWriteString (fd, FC_GLOBAL_MAGIC_COOKIE);
 423     sprintf (header, "%8x ", (int)truncate_to);
 424     strcat (header, current_arch_machine_name);
 425     if (!FcCacheWriteString (fd, header))
 426         goto bail4;
 427
 428     for (dir = cache->dirs; dir; dir = dir->next)
 429     {
 430         if (dir->name)
 431         {
 432             const char * d = (const char *)FcConfigNormalizeFontDir (config, (const FcChar8 *)dir->name);
 433
 434             FcCacheWriteString (fd, d);
 435             write (fd, &dir->metadata, sizeof(FcCache));
 436             lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_CUR)), SEEK_SET);
 437             write (fd, dir->ent, dir->metadata.count);
 438             free (dir->ent);
 439         }
 440     }
 441     FcCacheWriteString (fd, "");
 442
 443     if (close (fd) == -1)
 444         goto bail25;
 445
 446     if (!FcAtomicReplaceOrig (atomic))
 447         goto bail25;
 448
 449     FcAtomicUnlock (atomic);
 450     FcAtomicDestroy (atomic);
 451
 452     cache->updated = FcFalse;
 453     return FcTrue;
 454
 455  bail4:
 456     free (header);
 457  bail3:
 458     if (fd_orig != -1)
 459         close (fd_orig);
 460
 461     close (fd);
 462  bail25:
 463     FcAtomicDeleteNew (atomic);
 464  bail2:
 465     FcAtomicUnlock (atomic);
 466  bail1:
 467     FcAtomicDestroy (atomic);
 468     return FcFalse;
 469 }
 470
 471 /*
 472  * Find the next presumably-mmapable offset after the supplied file
 473  * position.
 474  */
 475 static int
 476 FcCacheNextOffset(off_t w)
 477 {
 478     static long pagesize = -1;
 479     if (pagesize == -1)
 480         pagesize = sysconf(_SC_PAGESIZE);
 481     if (w % pagesize == 0)
 482         return w;
 483     else
 484         return ((w / pagesize)+1)*pagesize;
 485 }
 486
 487 /* return the address of the segment for the provided arch,
 488  * or -1 if arch not found */
 489 static off_t
 490 FcCacheSkipToArch (int fd, const char * arch)
 491 {
 492     char candidate_arch_machine_name_count[MACHINE_SIGNATURE_SIZE + 9];
 493     char * candidate_arch;
 494     off_t current_arch_start = 0;
 495
 496     lseek (fd, 0, SEEK_SET);
 497     FcCacheSkipString (fd);
 498     current_arch_start = lseek (fd, 0, SEEK_CUR);
 499
 500     /* skip arches that are not the current arch */
 501     while (1)
 502     {
 503         long bs;
 504
 505         if (lseek (fd, current_arch_start, SEEK_SET) != current_arch_start)
 506             return -1;
 507
 508         if (FcCacheReadString (fd, candidate_arch_machine_name_count,
 509                                 sizeof (candidate_arch_machine_name_count)) == 0)
 510             return -1;
 511         if (!strlen(candidate_arch_machine_name_count))
 512             return -1;
 513         bs = strtol(candidate_arch_machine_name_count, &candidate_arch, 16);
 514
 515         // count = 0 should probably be distinguished from the !bs condition
 516         if (!bs || bs < strlen (candidate_arch_machine_name_count))
 517             return -1;
 518
 519         candidate_arch++; /* skip leading space */
 520
 521         if (strcmp (candidate_arch, arch)==0)
 522             return current_arch_start;
 523         current_arch_start += bs;
 524     }
 525
 526     return -1;
 527 }
 528
 529 /* Cuts out the segment at the file pointer (moves everything else
 530  * down to cover it), and leaves the file pointer at the end of the
 531  * file. */
 532 static FcBool
 533 FcCacheCopyOld (int fd, int fd_orig, off_t start)
 534 {
 535     char * buf = malloc (8192);
 536     char candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 537     long bs;
 538     int c, bytes_skipped;
 539     off_t loc;
 540
 541     if (!buf)
 542         return FcFalse;
 543
 544     loc = 0;
 545     lseek (fd, 0, SEEK_SET); lseek (fd_orig, 0, SEEK_SET);
 546     do
 547     {
 548         int b = 8192;
 549         if (loc + b > start)
 550             b = start - loc;
 551
 552         if ((c = read (fd_orig, buf, b)) <= 0)
 553             break;
 554         if (write (fd, buf, c) < 0)
 555             goto bail;
 556
 557         loc += c;
 558     }
 559     while (c > 0);
 560
 561     lseek (fd, start, SEEK_SET);
 562     if (FcCacheReadString (fd, candidate_arch_machine_name,
 563                            sizeof (candidate_arch_machine_name)) == 0)
 564         goto done;
 565     if (!strlen(candidate_arch_machine_name))
 566         goto done;
 567
 568     bs = strtol(candidate_arch_machine_name, 0, 16);
 569     if (bs == 0)
 570         goto done;
 571
 572     bytes_skipped = 0;
 573     do
 574     {
 575         lseek (fd, start+bs+bytes_skipped, SEEK_SET);
 576         if ((c = read (fd, buf, 8192)) <= 0)
 577             break;
 578         lseek (fd, start+bytes_skipped, SEEK_SET);
 579         if (write (fd, buf, c) < 0)
 580             goto bail;
 581         bytes_skipped += c;
 582     }
 583     while (c > 0);
 584     lseek (fd, start+bytes_skipped, SEEK_SET);
 585
 586  done:
 587     free (buf);
 588     return FcTrue;
 589
 590  bail:
 591     free (buf);
 592     return FcFalse;
 593 }
 594
 595 /* Does not check that the cache has the appropriate arch section. */
 596 /* Also, this can be fooled if the original location has a stale
 597  * cache, and the hashed location has an up-to-date cache.  Oh well,
 598  * sucks to be you in that case! */
 599 FcBool
 600 FcDirCacheValid (const FcChar8 *dir)
 601 {
 602     struct stat file_stat, dir_stat;
 603     int         fd;
 604
 605     if (stat ((char *) dir, &dir_stat) < 0)
 606         return FcFalse;
 607
 608     fd = FcDirCacheOpen (dir);
 609
 610     if (fd < 0)
 611         goto bail;
 612     if (fstat (fd, &file_stat) < 0)
 613         goto bail;
 614
 615     close (fd);
 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  bail:
 627     close (fd);
 628     return FcFalse;
 629 }
 630
 631 /* Assumes that the cache file in 'dir' exists.
 632  * Checks that the cache has the appropriate arch section. */
 633 FcBool
 634 FcDirCacheHasCurrentArch (const FcChar8 *dir)
 635 {
 636     int         fd;
 637     off_t       current_arch_start;
 638     char        *current_arch_machine_name;
 639
 640     fd = FcDirCacheOpen (dir);
 641     if (fd < 0)
 642         goto bail;
 643
 644     current_arch_machine_name = FcCacheMachineSignature();
 645     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 646     close (fd);
 647
 648     if (current_arch_start < 0)
 649         return FcFalse;
 650
 651     return FcTrue;
 652
 653  bail:
 654     return FcFalse;
 655 }
 656
 657 FcBool
 658 FcDirCacheUnlink (const FcChar8 *dir, FcConfig *config)
 659 {
 660     char        *cache_file;
 661     char        *cache_hashed = 0;
 662     int         fd, collisions;
 663     struct stat cache_stat;
 664     char        name_buf[FC_MAX_FILE_LEN];
 665
 666     dir = FcConfigNormalizeFontDir (config, dir);
 667     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 668     if (!cache_file)
 669         return FcFalse;
 670
 671     /* First remove normal cache file. */
 672     if (stat ((char *) cache_file, &cache_stat) == 0 &&
 673         unlink ((char *)cache_file) != 0)
 674         goto bail;
 675
 676     /* Next remove any applicable hashed files. */
 677     fd = -1; collisions = 0;
 678     do
 679     {
 680         if (cache_hashed)
 681             FcStrFree ((FcChar8 *)cache_hashed);
 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         {
 699             FcStrFree ((FcChar8 *)cache_hashed);
 700             goto bail;
 701         }
 702     } while (strcmp (name_buf, cache_file) != 0);
 703
 704     FcStrFree ((FcChar8 *)cache_file);
 705     close (fd);
 706
 707     if (stat ((char *) cache_hashed, &cache_stat) == 0 &&
 708         unlink ((char *)cache_hashed) != 0)
 709     {
 710         FcStrFree ((FcChar8 *)cache_hashed);
 711         goto bail;
 712     }
 713
 714     FcStrFree ((FcChar8 *)cache_hashed);
 715     return FcTrue;
 716
 717  bail:
 718     FcStrFree ((FcChar8 *)cache_file);
 719     return FcFalse;
 720 }
 721
 722 static int
 723 FcCacheReadDirs (FcConfig * config, FcGlobalCache * cache,
 724                  FcStrList *list, FcFontSet * set)
 725 {
 726     int                 ret = 0;
 727     FcChar8             *dir;
 728     FcChar8             *file, *base;
 729     FcStrSet            *subdirs;
 730     FcStrList           *sublist;
 731     struct stat         statb;
 732
 733     /*
 734      * Read in the results from 'list'.
 735      */
 736     while ((dir = FcStrListNext (list)))
 737     {
 738         if (!FcConfigAcceptFilename (config, dir))
 739             continue;
 740
 741         /* freed below */
 742         file = (FcChar8 *) malloc (strlen ((char *) dir) + 1 + FC_MAX_FILE_LEN + 1);
 743         if (!file)
 744             return FcFalse;
 745
 746         strcpy ((char *) file, (char *) dir);
 747         strcat ((char *) file, "/");
 748         base = file + strlen ((char *) file);
 749
 750         subdirs = FcStrSetCreate ();
 751         if (!subdirs)
 752         {
 753             fprintf (stderr, "Can't create directory set\n");
 754             ret++;
 755             free (file);
 756             continue;
 757         }
 758
 759         if (access ((char *) dir, X_OK) < 0)
 760         {
 761             switch (errno) {
 762             case ENOENT:
 763             case ENOTDIR:
 764             case EACCES:
 765                 break;
 766             default:
 767                 fprintf (stderr, "\"%s\": ", dir);
 768                 perror ("");
 769                 ret++;
 770             }
 771             FcStrSetDestroy (subdirs);
 772             free (file);
 773             continue;
 774         }
 775         if (stat ((char *) dir, &statb) == -1)
 776         {
 777             fprintf (stderr, "\"%s\": ", dir);
 778             perror ("");
 779             FcStrSetDestroy (subdirs);
 780             ret++;
 781             free (file);
 782             continue;
 783         }
 784         if (!S_ISDIR (statb.st_mode))
 785         {
 786             fprintf (stderr, "\"%s\": not a directory, skipping\n", dir);
 787             FcStrSetDestroy (subdirs);
 788             free (file);
 789             continue;
 790         }
 791         if (!FcDirCacheValid (dir) || !FcDirCacheRead (set, subdirs, dir, config))
 792         {
 793             if (FcDebug () & FC_DBG_FONTSET)
 794                 printf ("cache scan dir %s\n", dir);
 795
 796             FcDirScanConfig (set, subdirs, cache,
 797                              config->blanks, dir, FcFalse, config);
 798         }
 799         sublist = FcStrListCreate (subdirs);
 800         FcStrSetDestroy (subdirs);
 801         if (!sublist)
 802         {
 803             fprintf (stderr, "Can't create subdir list in \"%s\"\n", dir);
 804             ret++;
 805             free (file);
 806             continue;
 807         }
 808         ret += FcCacheReadDirs (config, cache, sublist, set);
 809         free (file);
 810     }
 811     FcStrListDone (list);
 812     return ret;
 813 }
 814
 815 FcFontSet *
 816 FcCacheRead (FcConfig *config, FcGlobalCache * cache)
 817 {
 818     FcFontSet * s = FcFontSetCreate();
 819     if (!s)
 820         return 0;
 821
 822     if (FcCacheReadDirs (config, cache, FcConfigGetConfigDirs (config), s))
 823         goto bail;
 824
 825     return s;
 826
 827  bail:
 828     FcFontSetDestroy (s);
 829     return 0;
 830 }
 831
 832 static const char bin2hex[] = { '0', '1', '2', '3',
 833                                 '4', '5', '6', '7',
 834                                 '8', '9', 'a', 'b',
 835                                 'c', 'd', 'e', 'f' };
 836
 837 static char *
 838 FcDirCacheHashName (char * cache_file, int collisions)
 839 {
 840     unsigned char       hash[16], hex_hash[33];
 841     char                *cache_hashed;
 842     unsigned char       uscore = '_';
 843     int                 cnt, i;
 844     FcChar8             *tmp;
 845     struct MD5Context   ctx;
 846
 847     MD5Init (&ctx);
 848     MD5Update (&ctx, (unsigned char *)cache_file, strlen (cache_file));
 849
 850     for (i = 0; i < collisions; i++)
 851         MD5Update (&ctx, &uscore, 1);
 852
 853     MD5Final (hash, &ctx);
 854
 855     for (cnt = 0; cnt < 16; ++cnt)
 856     {
 857         hex_hash[2*cnt] = bin2hex[hash[cnt] >> 4];
 858         hex_hash[2*cnt+1] = bin2hex[hash[cnt] & 0xf];
 859     }
 860     hex_hash[32] = 0;
 861
 862     tmp = FcStrPlus ((FcChar8 *)hex_hash, (FcChar8 *)FC_CACHE_SUFFIX);
 863     if (!tmp)
 864         return 0;
 865
 866     cache_hashed = (char *)FcStrPlus ((FcChar8 *)PKGCACHEDIR"/", tmp);
 867     free (tmp);
 868
 869     return cache_hashed;
 870 }
 871
 872 /* Opens the hashed name for cache_file.
 873  * This would fail in the unlikely event of a collision and subsequent
 874  * removal of the file which originally caused the collision. */
 875 static int
 876 FcDirCacheOpen (const FcChar8 *dir)
 877 {
 878     FcBool      found;
 879     int         fd = -1, collisions = 0;
 880     char        *cache_file, *cache_hashed;
 881     char        name_buf[FC_MAX_FILE_LEN];
 882     struct stat dir_stat;
 883
 884     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 885     if (!cache_file)
 886         return -1;
 887
 888     fd = open(cache_file, O_RDONLY);
 889     if (fd != -1)
 890         return fd;
 891
 892     if (stat ((char *)dir, &dir_stat) == -1)
 893         return -1;
 894
 895     found = FcFalse;
 896     do
 897     {
 898         struct stat c;
 899         FcChar8 * name_buf_dir;
 900
 901         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
 902         if (!cache_hashed)
 903         {
 904             FcStrFree ((FcChar8 *)cache_file);
 905             return -1;
 906         }
 907
 908         if (fd > 0)
 909             close (fd);
 910         fd = open(cache_hashed, O_RDONLY);
 911         FcStrFree ((FcChar8 *)cache_hashed);
 912
 913         if (fd == -1)
 914         {
 915             FcStrFree ((FcChar8 *)cache_file);
 916             return -1;
 917         }
 918         FcCacheReadString (fd, name_buf, sizeof (name_buf));
 919         if (!strlen(name_buf))
 920             goto bail;
 921
 922         name_buf_dir = FcStrDirname ((FcChar8 *)name_buf);
 923         if (stat ((char *)name_buf_dir, &c) == -1)
 924         {
 925             FcStrFree (name_buf_dir);
 926             continue;
 927         }
 928         FcStrFree (name_buf_dir);
 929         found = (c.st_ino == dir_stat.st_ino) && (c.st_dev == dir_stat.st_dev);
 930     } while (!found);
 931     FcStrFree ((FcChar8 *)cache_file);
 932     return fd;
 933
 934  bail:
 935     FcStrFree ((FcChar8 *)cache_file);
 936     close (fd);
 937     return -1;
 938 }
 939
 940 /* read serialized state from the cache file */
 941 FcBool
 942 FcDirCacheRead (FcFontSet * set, FcStrSet * dirs, const FcChar8 *dir, FcConfig *config)
 943 {
 944     int         fd;
 945     char        *current_arch_machine_name;
 946     char        candidate_arch_machine_name[9+MACHINE_SIGNATURE_SIZE];
 947     off_t       current_arch_start = 0;
 948     char        subdirName[FC_MAX_FILE_LEN + 1 + 12 + 1];
 949
 950     fd = FcDirCacheOpen (dir);
 951     if (fd < 0)
 952         goto bail;
 953
 954     current_arch_machine_name = FcCacheMachineSignature();
 955     current_arch_start = FcCacheSkipToArch(fd,
 956                                            current_arch_machine_name);
 957     if (current_arch_start < 0)
 958         goto bail1;
 959
 960     lseek (fd, current_arch_start, SEEK_SET);
 961     if (FcCacheReadString (fd, candidate_arch_machine_name,
 962                            sizeof (candidate_arch_machine_name)) == 0)
 963         goto bail1;
 964
 965     while (strlen(FcCacheReadString (fd, subdirName, sizeof (subdirName))) > 0)
 966         FcStrSetAdd (dirs, (FcChar8 *)subdirName);
 967
 968     if (!FcDirCacheConsume (fd, (const char *)dir, set, config))
 969         goto bail1;
 970
 971     close(fd);
 972     return FcTrue;
 973
 974  bail1:
 975     close (fd);
 976  bail:
 977     return FcFalse;
 978 }
 979
 980 static FcBool
 981 FcDirCacheConsume (int fd, const char * dir, FcFontSet *set, FcConfig *config)
 982 {
 983     FcCache metadata;
 984     void * current_dir_block;
 985     off_t pos;
 986
 987     read(fd, &metadata, sizeof(FcCache));
 988     if (metadata.magic != FC_CACHE_MAGIC)
 989         return FcFalse;
 990
 991     if (!metadata.count)
 992     {
 993         pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
 994         lseek (fd, pos, SEEK_SET);
 995         if (config)
 996             FcConfigAddFontDir (config, (FcChar8 *)dir);
 997         return FcTrue;
 998     }
 999
1000     pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
1001     current_dir_block = mmap (0, metadata.count,
1002                               PROT_READ, MAP_SHARED, fd, pos);
1003     lseek (fd, pos+metadata.count, SEEK_SET);
1004     if (current_dir_block == MAP_FAILED)
1005         return FcFalse;
1006
1007     FcCacheAddBankDir (metadata.bank, dir);
1008     if (config)
1009         FcConfigAddFontDir (config, (FcChar8 *)dir);
1010
1011     if (!FcFontSetUnserialize (&metadata, set, current_dir_block))
1012         return FcFalse;
1013
1014     return FcTrue;
1015 }
1016
1017 static void *
1018 FcDirCacheProduce (FcFontSet *set, FcCache *metadata)
1019 {
1020     void * current_dir_block, * final_dir_block;
1021     static unsigned int rand_state = 0;
1022     int bank, needed_bytes_no_align;
1023
1024     if (!rand_state)
1025         rand_state = time(0L);
1026     bank = rand_r(&rand_state);
1027
1028     while (FcCacheHaveBank(bank))
1029         bank = rand_r(&rand_state);
1030
1031     memset (metadata, 0, sizeof(FcCache));
1032     FcFontSetNewBank();
1033     needed_bytes_no_align = FcFontSetNeededBytes (set);
1034     metadata->count = needed_bytes_no_align +
1035         FcFontSetNeededBytesAlign ();
1036     metadata->magic = FC_CACHE_MAGIC;
1037     metadata->bank = bank;
1038
1039     if (!needed_bytes_no_align) /* not a failure, no fonts to write */
1040     {
1041         /* no, you don't really need to write any bytes at all. */
1042         metadata->count = 0;
1043         return 0;
1044     }
1045
1046     current_dir_block = malloc (metadata->count);
1047     if (!current_dir_block)
1048         goto bail;
1049     // shut up valgrind
1050     memset (current_dir_block, 0, metadata->count);
1051     final_dir_block = FcFontSetDistributeBytes (metadata, current_dir_block);
1052
1053     if ((void *)((char *)current_dir_block+metadata->count) < final_dir_block)
1054         goto bail;
1055
1056     if (!FcFontSetSerialize (bank, set))
1057         goto bail;
1058
1059     return current_dir_block;
1060
1061  bail:
1062     free (current_dir_block);
1063     return 0;
1064 }
1065
1066 /* write serialized state to the cache file */
1067 FcBool
1068 FcDirCacheWrite (FcFontSet *set, FcStrSet *dirs, const FcChar8 *dir)
1069 {
1070     char            *cache_file;
1071     char            *cache_hashed;
1072     int             fd, fd_orig, i, dirs_count;
1073     FcAtomic        *atomic;
1074     FcCache         metadata;
1075     off_t           current_arch_start = 0, truncate_to;
1076     char            name_buf[FC_MAX_FILE_LEN];
1077     int             collisions;
1078
1079     char            *current_arch_machine_name, * header;
1080     void            *current_dir_block = 0;
1081
1082     dir = FcConfigNormalizeFontDir (FcConfigGetCurrent(), dir);
1083     if (!dir)
1084         return FcFalse;
1085
1086     cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
1087     if (!cache_file)
1088         goto bail;
1089
1090     /* Ensure that we're not trampling a cache for some other dir. */
1091     /* This is slightly different from FcDirCacheOpen, since it
1092      * needs the filename, not the file descriptor. */
1093     fd = -1; collisions = 0;
1094     do
1095     {
1096         cache_hashed = FcDirCacheHashName (cache_file, collisions++);
1097         if (!cache_hashed)
1098             goto bail0;
1099
1100         if (fd > 0)
1101             close (fd);
1102         fd = open(cache_hashed, O_RDONLY);
1103         if (fd == -1)
1104             break;
1105         FcCacheReadString (fd, name_buf, sizeof (name_buf));
1106         close (fd);
1107
1108         if (!strlen(name_buf))
1109             break;
1110
1111         if (strcmp (name_buf, cache_file) != 0)
1112             continue;
1113     } while (0);
1114
1115     current_dir_block = FcDirCacheProduce (set, &metadata);
1116
1117     if (metadata.count && !current_dir_block)
1118         goto bail1;
1119
1120     if (FcDebug () & FC_DBG_CACHE)
1121         printf ("FcDirCacheWriteDir cache_file \"%s\"\n", cache_file);
1122
1123     atomic = FcAtomicCreate ((FcChar8 *)cache_hashed);
1124     if (!atomic)
1125         goto bail1;
1126
1127     if (!FcAtomicLock (atomic))
1128     {
1129         /* Now try rewriting the original version of the file. */
1130         FcAtomicDestroy (atomic);
1131
1132         atomic = FcAtomicCreate ((FcChar8 *)cache_file);
1133         fd_orig = open (cache_file, O_RDONLY);
1134         if (fd_orig == -1)
1135             fd_orig = open((char *)FcAtomicOrigFile (atomic), O_RDONLY);
1136
1137         fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT, 0666);
1138         if (fd == -1)
1139             goto bail2;
1140     }
1141
1142     /* In all cases, try opening the real location of the cache file first. */
1143     /* (even if that's not atomic.) */
1144     fd_orig = open (cache_file, O_RDONLY);
1145     if (fd_orig == -1)
1146         fd_orig = open((char *)FcAtomicOrigFile (atomic), O_RDONLY);
1147
1148     fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT, 0666);
1149     if (fd == -1)
1150         goto bail3;
1151
1152     FcCacheWriteString (fd, cache_file);
1153
1154     current_arch_machine_name = FcCacheMachineSignature ();
1155     current_arch_start = 0;
1156
1157     if (fd_orig != -1)
1158         current_arch_start =
1159             FcCacheSkipToArch(fd_orig, current_arch_machine_name);
1160
1161     if (current_arch_start < 0)
1162         current_arch_start = FcCacheNextOffset (lseek(fd_orig, 0, SEEK_END));
1163
1164     if (fd_orig != -1 && !FcCacheCopyOld(fd, fd_orig, current_arch_start))
1165         goto bail4;
1166
1167     if (fd_orig != -1)
1168         close (fd_orig);
1169
1170     current_arch_start = lseek(fd, 0, SEEK_CUR);
1171     if (ftruncate (fd, current_arch_start) == -1)
1172         goto bail4;
1173
1174     /* allocate space for subdir names in this block */
1175     dirs_count = 0;
1176     for (i = 0; i < dirs->size; i++)
1177         dirs_count += strlen((char *)dirs->strs[i]) + 1;
1178     dirs_count ++;
1179
1180     /* now write the address of the next offset */
1181     truncate_to = FcCacheNextOffset (FcCacheNextOffset (current_arch_start + sizeof (FcCache) + dirs_count) + metadata.count) - current_arch_start;
1182     header = malloc (10 + strlen (current_arch_machine_name));
1183     if (!header)
1184         goto bail4;
1185     sprintf (header, "%8x ", (int)truncate_to);
1186     strcat (header, current_arch_machine_name);
1187     if (!FcCacheWriteString (fd, header))
1188         goto bail5;
1189
1190     for (i = 0; i < dirs->size; i++)
1191         FcCacheWriteString (fd, (char *)dirs->strs[i]);
1192     FcCacheWriteString (fd, "");
1193
1194     write (fd, &metadata, sizeof(FcCache));
1195     if (metadata.count)
1196     {
1197         lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_END)), SEEK_SET);
1198         write (fd, current_dir_block, metadata.count);
1199         free (current_dir_block);
1200     }
1201
1202     /* this actually serves to pad out the cache file, if needed */
1203     if (ftruncate (fd, current_arch_start + truncate_to) == -1)
1204         goto bail5;
1205
1206     free (header);
1207     close(fd);
1208     if (!FcAtomicReplaceOrig(atomic))
1209         goto bail5;
1210     FcStrFree ((FcChar8 *)cache_hashed);
1211     FcStrFree ((FcChar8 *)cache_file);
1212     FcAtomicUnlock (atomic);
1213     FcAtomicDestroy (atomic);
1214     return FcTrue;
1215
1216  bail5:
1217     free (header);
1218  bail4:
1219     close (fd);
1220  bail3:
1221     FcAtomicUnlock (atomic);
1222  bail2:
1223     FcAtomicDestroy (atomic);
1224  bail1:
1225     FcStrFree ((FcChar8 *)cache_hashed);
1226  bail0:
1227     unlink ((char *)cache_file);
1228     FcStrFree ((FcChar8 *)cache_file);
1229     if (current_dir_block)
1230         free (current_dir_block);
1231  bail:
1232     return FcFalse;
1233 }
1234
1235 static char *
1236 FcCacheMachineSignature ()
1237 {
1238     static char buf[MACHINE_SIGNATURE_SIZE];
1239     int32_t magic = ENDIAN_TEST;
1240     char * m = (char *)&magic;
1241
1242     sprintf (buf, "%2x%2x%2x%2x "
1243              "%4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x "
1244              "%4x %4x %4x %4x %4x %4x %4x %4x\n",
1245              m[0], m[1], m[2], m[3],
1246              (unsigned int)sizeof (char),
1247              (unsigned int)sizeof (char *),
1248              (unsigned int)sizeof (int),
1249              (unsigned int)sizeof (FcPattern),
1250              (unsigned int)sizeof (FcPatternEltPtr),
1251              (unsigned int)sizeof (struct _FcPatternElt *),
1252              (unsigned int)sizeof (FcPatternElt),
1253              (unsigned int)sizeof (FcObjectPtr),
1254              (unsigned int)sizeof (FcValueListPtr),
1255              (unsigned int)sizeof (FcValue),
1256              (unsigned int)sizeof (FcValueBinding),
1257              (unsigned int)sizeof (struct _FcValueList *),
1258              (unsigned int)sizeof (FcCharSet),
1259              (unsigned int)sizeof (FcCharLeaf **),
1260              (unsigned int)sizeof (FcChar16 *),
1261              (unsigned int)sizeof (FcChar16),
1262              (unsigned int)sizeof (FcCharLeaf),
1263              (unsigned int)sizeof (FcChar32),
1264              (unsigned int)sizeof (FcCache),
1265              (unsigned int)sysconf(_SC_PAGESIZE));
1266
1267     return buf;
1268 }
1269
1270 static int banks_ptr = 0, banks_alloc = 0;
1271 int * _fcBankId = 0, * _fcBankIdx = 0;
1272 static const char ** bankDirs = 0;
1273
1274 static FcBool
1275 FcCacheHaveBank (int bank)
1276 {
1277     int i;
1278
1279     if (bank < FC_BANK_FIRST)
1280         return FcTrue;
1281
1282     for (i = 0; i < banks_ptr; i++)
1283         if (_fcBankId[i] == bank)
1284             return FcTrue;
1285
1286     return FcFalse;
1287 }
1288
1289 int
1290 FcCacheBankToIndexMTF (int bank)
1291 {
1292     int i, j;
1293
1294     for (i = 0; i < banks_ptr; i++)
1295         if (_fcBankId[_fcBankIdx[i]] == bank)
1296         {
1297             int t = _fcBankIdx[i];
1298
1299             for (j = i; j > 0; j--)
1300                 _fcBankIdx[j] = _fcBankIdx[j-1];
1301             _fcBankIdx[0] = t;
1302             return t;
1303         }
1304
1305     if (banks_ptr >= banks_alloc)
1306     {
1307         int * b, * bidx;
1308         const char ** bds;
1309
1310         b = realloc (_fcBankId, (banks_alloc + 4) * sizeof(int));
1311         if (!b)
1312             return -1;
1313         _fcBankId = b;
1314
1315         bidx = realloc (_fcBankIdx, (banks_alloc + 4) * sizeof(int));
1316         if (!bidx)
1317             return -1;
1318         _fcBankIdx = bidx;
1319
1320         bds = realloc (bankDirs, (banks_alloc + 4) * sizeof (char *));
1321         if (!bds)
1322             return -1;
1323         bankDirs = bds;
1324
1325         banks_alloc += 4;
1326     }
1327
1328     i = banks_ptr++;
1329     _fcBankId[i] = bank;
1330     _fcBankIdx[i] = i;
1331     return i;
1332 }
1333
1334 static void
1335 FcCacheAddBankDir (int bank, const char * dir)
1336 {
1337     int bi = FcCacheBankToIndexMTF (bank);
1338
1339     if (bi < 0)
1340         return;
1341
1342     bankDirs[bi] = (const char *)FcStrCopy ((FcChar8 *)dir);
1343 }
1344
1345 const char *
1346 FcCacheFindBankDir (int bank)
1347 {
1348     int bi = FcCacheBankToIndex (bank);
1349     return bankDirs[bi];
1350 }
1351
1352 /*
1353  * This code implements the MD5 message-digest algorithm.
1354  * The algorithm is due to Ron Rivest.  This code was
1355  * written by Colin Plumb in 1993, no copyright is claimed.
1356  * This code is in the public domain; do with it what you wish.
1357  *
1358  * Equivalent code is available from RSA Data Security, Inc.
1359  * This code has been tested against that, and is equivalent,
1360  * except that you don't need to include two pages of legalese
1361  * with every copy.
1362  *
1363  * To compute the message digest of a chunk of bytes, declare an
1364  * MD5Context structure, pass it to MD5Init, call MD5Update as
1365  * needed on buffers full of bytes, and then call MD5Final, which
1366  * will fill a supplied 16-byte array with the digest.
1367  */
1368
1369 #ifndef HIGHFIRST
1370 #define byteReverse(buf, len)   /* Nothing */
1371 #else
1372 /*
1373  * Note: this code is harmless on little-endian machines.
1374  */
1375 void byteReverse(unsigned char *buf, unsigned longs)
1376 {
1377     FcChar32 t;
1378     do {
1379         t = (FcChar32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
1380             ((unsigned) buf[1] << 8 | buf[0]);
1381         *(FcChar32 *) buf = t;
1382         buf += 4;
1383     } while (--longs);
1384 }
1385 #endif
1386
1387 /*
1388  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
1389  * initialization constants.
1390  */
1391 static void MD5Init(struct MD5Context *ctx)
1392 {
1393     ctx->buf[0] = 0x67452301;
1394     ctx->buf[1] = 0xefcdab89;
1395     ctx->buf[2] = 0x98badcfe;
1396     ctx->buf[3] = 0x10325476;
1397
1398     ctx->bits[0] = 0;
1399     ctx->bits[1] = 0;
1400 }
1401
1402 /*
1403  * Update context to reflect the concatenation of another buffer full
1404  * of bytes.
1405  */
1406 static void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len)
1407 {
1408     FcChar32 t;
1409
1410     /* Update bitcount */
1411
1412     t = ctx->bits[0];
1413     if ((ctx->bits[0] = t + ((FcChar32) len << 3)) < t)
1414         ctx->bits[1]++;         /* Carry from low to high */
1415     ctx->bits[1] += len >> 29;
1416
1417     t = (t >> 3) & 0x3f;        /* Bytes already in shsInfo->data */
1418
1419     /* Handle any leading odd-sized chunks */
1420
1421     if (t) {
1422         unsigned char *p = (unsigned char *) ctx->in + t;
1423
1424         t = 64 - t;
1425         if (len < t) {
1426             memcpy(p, buf, len);
1427             return;
1428         }
1429         memcpy(p, buf, t);
1430         byteReverse(ctx->in, 16);
1431         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1432         buf += t;
1433         len -= t;
1434     }
1435     /* Process data in 64-byte chunks */
1436
1437     while (len >= 64) {
1438         memcpy(ctx->in, buf, 64);
1439         byteReverse(ctx->in, 16);
1440         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1441         buf += 64;
1442         len -= 64;
1443     }
1444
1445     /* Handle any remaining bytes of data. */
1446
1447     memcpy(ctx->in, buf, len);
1448 }
1449
1450 /*
1451  * Final wrapup - pad to 64-byte boundary with the bit pattern
1452  * 1 0* (64-bit count of bits processed, MSB-first)
1453  */
1454 static void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
1455 {
1456     unsigned count;
1457     unsigned char *p;
1458
1459     /* Compute number of bytes mod 64 */
1460     count = (ctx->bits[0] >> 3) & 0x3F;
1461
1462     /* Set the first char of padding to 0x80.  This is safe since there is
1463        always at least one byte free */
1464     p = ctx->in + count;
1465     *p++ = 0x80;
1466
1467     /* Bytes of padding needed to make 64 bytes */
1468     count = 64 - 1 - count;
1469
1470     /* Pad out to 56 mod 64 */
1471     if (count < 8) {
1472         /* Two lots of padding:  Pad the first block to 64 bytes */
1473         memset(p, 0, count);
1474         byteReverse(ctx->in, 16);
1475         MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1476
1477         /* Now fill the next block with 56 bytes */
1478         memset(ctx->in, 0, 56);
1479     } else {
1480         /* Pad block to 56 bytes */
1481         memset(p, 0, count - 8);
1482     }
1483     byteReverse(ctx->in, 14);
1484
1485     /* Append length in bits and transform */
1486     ((FcChar32 *) ctx->in)[14] = ctx->bits[0];
1487     ((FcChar32 *) ctx->in)[15] = ctx->bits[1];
1488
1489     MD5Transform(ctx->buf, (FcChar32 *) ctx->in);
1490     byteReverse((unsigned char *) ctx->buf, 4);
1491     memcpy(digest, ctx->buf, 16);
1492     memset(ctx, 0, sizeof(ctx));        /* In case it's sensitive */
1493 }
1494
1495
1496 /* The four core functions - F1 is optimized somewhat */
1497
1498 /* #define F1(x, y, z) (x & y | ~x & z) */
1499 #define F1(x, y, z) (z ^ (x & (y ^ z)))
1500 #define F2(x, y, z) F1(z, x, y)
1501 #define F3(x, y, z) (x ^ y ^ z)
1502 #define F4(x, y, z) (y ^ (x | ~z))
1503
1504 /* This is the central step in the MD5 algorithm. */
1505 #define MD5STEP(f, w, x, y, z, data, s) \
1506         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
1507
1508 /*
1509  * The core of the MD5 algorithm, this alters an existing MD5 hash to
1510  * reflect the addition of 16 longwords of new data.  MD5Update blocks
1511  * the data and converts bytes into longwords for this routine.
1512  */
1513 static void MD5Transform(FcChar32 buf[4], FcChar32 in[16])
1514 {
1515     register FcChar32 a, b, c, d;
1516
1517     a = buf[0];
1518     b = buf[1];
1519     c = buf[2];
1520     d = buf[3];
1521
1522     MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
1523     MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
1524     MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
1525     MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
1526     MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
1527     MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
1528     MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
1529     MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
1530     MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
1531     MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
1532     MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
1533     MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
1534     MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
1535     MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
1536     MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
1537     MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
1538
1539     MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
1540     MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
1541     MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
1542     MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
1543     MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
1544     MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
1545     MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
1546     MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
1547     MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
1548     MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
1549     MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
1550     MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
1551     MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
1552     MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
1553     MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
1554     MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
1555
1556     MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
1557     MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
1558     MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
1559     MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
1560     MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
1561     MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
1562     MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
1563     MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
1564     MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
1565     MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
1566     MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
1567     MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
1568     MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
1569     MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
1570     MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
1571     MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
1572
1573     MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
1574     MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
1575     MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
1576     MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
1577     MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
1578     MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
1579     MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
1580     MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
1581     MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
1582     MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
1583     MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
1584     MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
1585     MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
1586     MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
1587     MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
1588     MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
1589
1590     buf[0] += a;
1591     buf[1] += b;
1592     buf[2] += c;
1593     buf[3] += d;
1594 }