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 <sys/mman.h>
  29 #include <sys/utsname.h>
  30 #include <sys/types.h>
  31 #include <unistd.h>
  32 #include "fcint.h"
  33
  34 #define ENDIAN_TEST 0x12345678
  35 #define MACHINE_SIGNATURE_SIZE 9 + 5*19 + 1
  36
  37 static off_t
  38 FcCacheSkipToArch (int fd, const char * arch);
  39
  40 static FcBool
  41 FcCacheMoveDown (int fd, off_t start);
  42
  43 static void *
  44 FcDirCacheProduce (FcFontSet *set, FcCache * metadata);
  45
  46 static FcBool
  47 FcDirCacheConsume (int fd, FcFontSet *set);
  48
  49 static FcBool
  50 FcDirCacheRead (FcFontSet * set, FcStrSet * dirs, const FcChar8 *dir);
  51
  52 static int
  53 FcCacheNextOffset(off_t w);
  54
  55 static char *
  56 FcCacheMachineSignature (void);
  57
  58 static FcBool
  59 FcCacheHaveBank (int bank);
  60
  61 #define FC_DBG_CACHE_REF    1024
  62
  63 static char *
  64 FcCacheReadString (int fd, char *dest, int len)
  65 {
  66     FcChar8     c;
  67     FcBool      escape;
  68     int         size;
  69     int         i;
  70
  71     if (len == 0)
  72         return 0;
  73
  74     size = len;
  75     i = 0;
  76     escape = FcFalse;
  77     while (read (fd, &c, 1) == 1)
  78     {
  79         if (!escape)
  80         {
  81             switch (c) {
  82             case '"':
  83                 c = '\0';
  84                 break;
  85             case '\\':
  86                 escape = FcTrue;
  87                 continue;
  88             }
  89         }
  90         if (i == size)
  91         {
  92             dest[i++] = 0;
  93             return dest;
  94         }
  95         dest[i++] = c;
  96         if (c == '\0')
  97             return dest;
  98         escape = FcFalse;
  99     }
 100     return 0;
 101 }
 102
 103 static FcBool
 104 FcCacheWriteString (int fd, const char *chars)
 105 {
 106     if (write (fd, chars, strlen(chars)+1) != strlen(chars)+1)
 107         return FcFalse;
 108     return FcTrue;
 109 }
 110
 111 static void
 112 FcGlobalCacheDirDestroy (FcGlobalCacheDir *d)
 113 {
 114     FcMemFree (FC_MEM_STRING, strlen (d->name)+1);
 115     free (d->name);
 116     FcMemFree (FC_MEM_CACHE, sizeof (FcGlobalCacheDir));
 117     free (d);
 118 }
 119
 120 FcGlobalCache *
 121 FcGlobalCacheCreate (void)
 122 {
 123     FcGlobalCache   *cache;
 124
 125     cache = malloc (sizeof (FcGlobalCache));
 126     if (!cache)
 127         return 0;
 128     FcMemAlloc (FC_MEM_CACHE, sizeof (FcGlobalCache));
 129     cache->dirs = 0;
 130     cache->updated = FcFalse;
 131     cache->fd = -1;
 132     return cache;
 133 }
 134
 135 void
 136 FcGlobalCacheDestroy (FcGlobalCache *cache)
 137 {
 138     FcGlobalCacheDir    *d, *next;
 139
 140     for (d = cache->dirs; d; d = next)
 141     {
 142         next = d->next;
 143         FcGlobalCacheDirDestroy (d);
 144     }
 145     FcMemFree (FC_MEM_CACHE, sizeof (FcGlobalCache));
 146     free (cache);
 147 }
 148
 149 void
 150 FcGlobalCacheLoad (FcGlobalCache    *cache,
 151                    FcStrSet         *staleDirs,
 152                    const FcChar8    *cache_file)
 153 {
 154     char                name_buf[8192];
 155     FcGlobalCacheDir    *d, *next;
 156     char                * current_arch_machine_name;
 157     char                candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 158     off_t               current_arch_start;
 159
 160     struct stat         cache_stat, dir_stat;
 161
 162     if (stat ((char *) cache_file, &cache_stat) < 0)
 163         return;
 164
 165     cache->fd = open ((char *) cache_file, O_RDONLY);
 166     if (cache->fd == -1)
 167         return;
 168
 169     cache->updated = FcFalse;
 170
 171     current_arch_machine_name = FcCacheMachineSignature ();
 172     current_arch_start = FcCacheSkipToArch(cache->fd,
 173                                            current_arch_machine_name);
 174     if (current_arch_start < 0)
 175         goto bail0;
 176
 177     lseek (cache->fd, current_arch_start, SEEK_SET);
 178     FcCacheReadString (cache->fd, candidate_arch_machine_name,
 179                        sizeof (candidate_arch_machine_name));
 180     if (strlen(candidate_arch_machine_name) == 0)
 181         goto bail0;
 182
 183     while (1)
 184     {
 185         off_t targ;
 186
 187         FcCacheReadString (cache->fd, name_buf, sizeof (name_buf));
 188         if (!strlen(name_buf))
 189             break;
 190
 191         if (stat ((char *) name_buf, &dir_stat) < 0 ||
 192             dir_stat.st_mtime > cache_stat.st_mtime)
 193         {
 194             FcCache md;
 195
 196             FcStrSetAdd (staleDirs, FcStrCopy ((FcChar8 *)name_buf));
 197             read (cache->fd, &md, sizeof (FcCache));
 198             lseek (cache->fd, FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + md.count, SEEK_SET);
 199             continue;
 200         }
 201
 202         d = malloc (sizeof (FcGlobalCacheDir));
 203         if (!d)
 204             goto bail1;
 205
 206         d->next = cache->dirs;
 207         cache->dirs = d;
 208
 209         d->name = (char *)FcStrCopy ((FcChar8 *)name_buf);
 210         d->ent = 0;
 211         d->offset = lseek (cache->fd, 0, SEEK_CUR);
 212         if (read (cache->fd, &d->metadata, sizeof (FcCache)) != sizeof (FcCache))
 213             goto bail1;
 214         targ = FcCacheNextOffset (lseek(cache->fd, 0, SEEK_CUR)) + d->metadata.count;
 215         if (lseek (cache->fd, targ, SEEK_SET) != targ)
 216             goto bail1;
 217     }
 218     return;
 219
 220  bail1:
 221     for (d = cache->dirs; d; d = next)
 222     {
 223         next = d->next;
 224         free (d);
 225     }
 226     cache->dirs = 0;
 227  bail0:
 228     close (cache->fd);
 229     cache->fd = -1;
 230     return;
 231 }
 232
 233 FcBool
 234 FcGlobalCacheReadDir (FcFontSet *set, FcStrSet *dirs, FcGlobalCache * cache, const char *dir, FcConfig *config)
 235 {
 236     FcGlobalCacheDir *d;
 237     FcBool ret = FcFalse;
 238
 239     if (cache->fd == -1)
 240         return FcFalse;
 241
 242     for (d = cache->dirs; d; d = d->next)
 243     {
 244         if (strncmp (d->name, dir, strlen(dir)) == 0)
 245         {
 246             lseek (cache->fd, d->offset, SEEK_SET);
 247             if (!FcDirCacheConsume (cache->fd, set))
 248                 return FcFalse;
 249             if (strcmp (d->name, dir) == 0)
 250                 ret = FcTrue;
 251         }
 252     }
 253
 254     return ret;
 255 }
 256
 257 FcBool
 258 FcGlobalCacheUpdate (FcGlobalCache  *cache,
 259                      const char     *name,
 260                      FcFontSet      *set)
 261 {
 262     FcGlobalCacheDir * d;
 263
 264     if (!set->nfont)
 265         return FcTrue;
 266
 267     for (d = cache->dirs; d; d = d->next)
 268     {
 269         if (strcmp(d->name, name) == 0)
 270             break;
 271     }
 272
 273     if (!d)
 274     {
 275         d = malloc (sizeof (FcGlobalCacheDir));
 276         if (!d)
 277             return FcFalse;
 278         d->next = cache->dirs;
 279         cache->dirs = d;
 280     }
 281
 282     cache->updated = FcTrue;
 283
 284     d->name = (char *)FcStrCopy ((FcChar8 *)name);
 285     d->ent = FcDirCacheProduce (set, &d->metadata);
 286     d->offset = 0;
 287     return FcTrue;
 288 }
 289
 290 FcBool
 291 FcGlobalCacheSave (FcGlobalCache    *cache,
 292                    const FcChar8    *cache_file)
 293 {
 294     int                 fd;
 295     FcGlobalCacheDir    *dir;
 296     FcAtomic            *atomic;
 297     off_t               current_arch_start = 0, truncate_to;
 298     char                * current_arch_machine_name, * header;
 299
 300     if (!cache->updated)
 301         return FcTrue;
 302
 303 #if defined (HAVE_GETUID) && defined (HAVE_GETEUID)
 304     /* Set-UID programs can't safely update the cache */
 305     if (getuid () != geteuid ())
 306         return FcFalse;
 307 #endif
 308
 309     atomic = FcAtomicCreate (cache_file);
 310     if (!atomic)
 311         goto bail0;
 312     if (!FcAtomicLock (atomic))
 313         goto bail1;
 314     fd = open ((char *) FcAtomicNewFile(atomic), O_RDWR | O_CREAT,
 315                S_IRUSR | S_IWUSR);
 316     if (fd == -1)
 317         goto bail2;
 318
 319     current_arch_machine_name = FcCacheMachineSignature ();
 320     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 321     if (current_arch_start < 0)
 322         current_arch_start = FcCacheNextOffset (lseek(fd, 0, SEEK_END));
 323
 324     if (!FcCacheMoveDown(fd, current_arch_start))
 325         goto bail2;
 326
 327     current_arch_start = lseek(fd, 0, SEEK_CUR);
 328     if (ftruncate (fd, current_arch_start) == -1)
 329         goto bail2;
 330
 331     header = malloc (10 + strlen (current_arch_machine_name));
 332     if (!header)
 333         goto bail1;
 334
 335     truncate_to = current_arch_start + strlen(current_arch_machine_name) + 11;
 336     for (dir = cache->dirs; dir; dir = dir->next)
 337     {
 338         truncate_to += strlen(dir->name) + 1;
 339         truncate_to += sizeof (FcCache);
 340         truncate_to = FcCacheNextOffset (current_arch_start + truncate_to);
 341         truncate_to += dir->metadata.count;
 342     }
 343     truncate_to -= current_arch_start;
 344
 345     sprintf (header, "%8x ", (int)truncate_to);
 346     strcat (header, current_arch_machine_name);
 347     if (!FcCacheWriteString (fd, header))
 348         goto bail1;
 349
 350     for (dir = cache->dirs; dir; dir = dir->next)
 351     {
 352         if (dir->ent)
 353         {
 354             FcCacheWriteString (fd, dir->name);
 355             write (fd, &dir->metadata, sizeof(FcCache));
 356             lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_CUR)), SEEK_SET);
 357             write (fd, dir->ent, dir->metadata.count);
 358             free (dir->ent);
 359         }
 360     }
 361     FcCacheWriteString (fd, "");
 362
 363     if (close (fd) == -1)
 364         goto bail3;
 365
 366     if (!FcAtomicReplaceOrig (atomic))
 367         goto bail3;
 368
 369     FcAtomicUnlock (atomic);
 370     FcAtomicDestroy (atomic);
 371
 372     cache->updated = FcFalse;
 373     return FcTrue;
 374
 375 bail3:
 376     FcAtomicDeleteNew (atomic);
 377 bail2:
 378     FcAtomicUnlock (atomic);
 379 bail1:
 380     FcAtomicDestroy (atomic);
 381 bail0:
 382     return FcFalse;
 383 }
 384
 385 #define PAGESIZE 8192
 386 /*
 387  * Find the next presumably-mmapable offset after the supplied file
 388  * position.
 389  */
 390 static int
 391 FcCacheNextOffset(off_t w)
 392 {
 393     if (w % PAGESIZE == 0)
 394         return w;
 395     else
 396         return ((w / PAGESIZE)+1)*PAGESIZE;
 397 }
 398
 399 /* return the address of the segment for the provided arch,
 400  * or -1 if arch not found */
 401 static off_t
 402 FcCacheSkipToArch (int fd, const char * arch)
 403 {
 404     char candidate_arch_machine_name_count[MACHINE_SIGNATURE_SIZE + 9];
 405     char * candidate_arch;
 406     off_t current_arch_start = 0;
 407
 408     /* skip arches that are not the current arch */
 409     while (1)
 410     {
 411         long bs;
 412
 413         if (lseek (fd, current_arch_start, SEEK_SET) != current_arch_start)
 414             return -1;
 415
 416         if (FcCacheReadString (fd, candidate_arch_machine_name_count,
 417                                 sizeof (candidate_arch_machine_name_count)) == 0)
 418             return -1;
 419         if (!strlen(candidate_arch_machine_name_count))
 420             return -1;
 421         bs = strtol(candidate_arch_machine_name_count, &candidate_arch, 16);
 422
 423         // count = 0 should probably be distinguished from the !bs condition
 424         if (!bs || bs < strlen (candidate_arch_machine_name_count))
 425             return -1;
 426
 427         candidate_arch++; /* skip leading space */
 428
 429         if (strcmp (candidate_arch, arch)==0)
 430             return current_arch_start;
 431         current_arch_start += bs;
 432     }
 433
 434     return -1;
 435 }
 436
 437 /* Cuts out the segment at the file pointer (moves everything else
 438  * down to cover it), and leaves the file pointer at the end of the
 439  * file. */
 440 static FcBool
 441 FcCacheMoveDown (int fd, off_t start)
 442 {
 443     char * buf = malloc (8192);
 444     char candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 445     long bs;
 446     int c, bytes_skipped;
 447
 448     if (!buf)
 449         return FcFalse;
 450
 451     lseek (fd, start, SEEK_SET);
 452     if (FcCacheReadString (fd, candidate_arch_machine_name,
 453                            sizeof (candidate_arch_machine_name)) == 0)
 454         goto done;
 455     if (!strlen(candidate_arch_machine_name))
 456         goto done;
 457
 458     bs = strtol(candidate_arch_machine_name, 0, 16);
 459     if (bs == 0)
 460         goto done;
 461
 462     bytes_skipped = 0;
 463     do
 464     {
 465         lseek (fd, start+bs+bytes_skipped, SEEK_SET);
 466         if ((c = read (fd, buf, 8192)) <= 0)
 467             break;
 468         lseek (fd, start+bytes_skipped, SEEK_SET);
 469         if (write (fd, buf, c) < 0)
 470             goto bail;
 471         bytes_skipped += c;
 472     }
 473     while (c > 0);
 474     lseek (fd, start+bytes_skipped, SEEK_SET);
 475
 476  done:
 477     free (buf);
 478     return FcTrue;
 479
 480  bail:
 481     free (buf);
 482     return FcFalse;
 483 }
 484
 485 FcBool
 486 FcDirCacheValid (const FcChar8 *dir)
 487 {
 488     FcChar8     *cache_file = FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 489     struct stat file_stat, dir_stat;
 490
 491     if (stat ((char *) dir, &dir_stat) < 0)
 492     {
 493         FcStrFree (cache_file);
 494         return FcFalse;
 495     }
 496     if (stat ((char *) cache_file, &file_stat) < 0)
 497     {
 498         FcStrFree (cache_file);
 499         return FcFalse;
 500     }
 501     FcStrFree (cache_file);
 502     /*
 503      * If the directory has been modified more recently than
 504      * the cache file, the cache is not valid
 505      */
 506     if (dir_stat.st_mtime - file_stat.st_mtime > 0)
 507         return FcFalse;
 508     return FcTrue;
 509 }
 510
 511 static int
 512 FcCacheReadDirs (FcConfig * config, FcGlobalCache * cache,
 513                  FcStrList *list, FcFontSet * set)
 514 {
 515     int                 ret = 0;
 516     FcChar8             *dir;
 517     FcChar8             *file, *base;
 518     FcStrSet            *subdirs;
 519     FcStrList           *sublist;
 520     struct stat         statb;
 521
 522     /*
 523      * Read in the results from 'list'.
 524      */
 525     while ((dir = FcStrListNext (list)))
 526     {
 527         /* freed below */
 528         file = (FcChar8 *) malloc (strlen ((char *) dir) + 1 + FC_MAX_FILE_LEN + 1);
 529         if (!file)
 530             return FcFalse;
 531
 532         strcpy ((char *) file, (char *) dir);
 533         strcat ((char *) file, "/");
 534         base = file + strlen ((char *) file);
 535
 536         subdirs = FcStrSetCreate ();
 537         if (!subdirs)
 538         {
 539             fprintf (stderr, "Can't create directory set\n");
 540             ret++;
 541             free (file);
 542             continue;
 543         }
 544
 545         if (access ((char *) dir, X_OK) < 0)
 546         {
 547             switch (errno) {
 548             case ENOENT:
 549             case ENOTDIR:
 550             case EACCES:
 551                 break;
 552             default:
 553                 fprintf (stderr, "\"%s\": ", dir);
 554                 perror ("");
 555                 ret++;
 556             }
 557             FcStrSetDestroy (subdirs);
 558             free (file);
 559             continue;
 560         }
 561         if (stat ((char *) dir, &statb) == -1)
 562         {
 563             fprintf (stderr, "\"%s\": ", dir);
 564             perror ("");
 565             FcStrSetDestroy (subdirs);
 566             ret++;
 567             free (file);
 568             continue;
 569         }
 570         if (!S_ISDIR (statb.st_mode))
 571         {
 572             fprintf (stderr, "\"%s\": not a directory, skipping\n", dir);
 573             FcStrSetDestroy (subdirs);
 574             free (file);
 575             continue;
 576         }
 577         if (!FcDirCacheValid (dir) || !FcDirCacheRead (set, subdirs, dir))
 578         {
 579             if (FcDebug () & FC_DBG_FONTSET)
 580                 printf ("cache scan dir %s\n", dir);
 581
 582             FcDirScanConfig (set, subdirs, cache,
 583                              config->blanks, dir, FcFalse, config);
 584         }
 585         sublist = FcStrListCreate (subdirs);
 586         FcStrSetDestroy (subdirs);
 587         if (!sublist)
 588         {
 589             fprintf (stderr, "Can't create subdir list in \"%s\"\n", dir);
 590             ret++;
 591             free (file);
 592             continue;
 593         }
 594         ret += FcCacheReadDirs (config, cache, sublist, set);
 595         free (file);
 596     }
 597     FcStrListDone (list);
 598     return ret;
 599 }
 600
 601 FcFontSet *
 602 FcCacheRead (FcConfig *config, FcGlobalCache * cache)
 603 {
 604     FcFontSet * s = FcFontSetCreate();
 605     if (!s)
 606         return 0;
 607
 608     if (FcCacheReadDirs (config, cache, FcConfigGetConfigDirs (config), s))
 609         goto bail;
 610
 611     return s;
 612
 613  bail:
 614     FcFontSetDestroy (s);
 615     return 0;
 616 }
 617
 618 /* read serialized state from the cache file */
 619 static FcBool
 620 FcDirCacheRead (FcFontSet * set, FcStrSet * dirs, const FcChar8 *dir)
 621 {
 622     char *cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 623     int fd;
 624     char * current_arch_machine_name;
 625     char candidate_arch_machine_name[9+MACHINE_SIGNATURE_SIZE];
 626     off_t current_arch_start = 0;
 627     char subdirName[FC_MAX_FILE_LEN + 1 + 12 + 1];
 628
 629     if (!cache_file)
 630         goto bail;
 631
 632     current_arch_machine_name = FcCacheMachineSignature();
 633     fd = open(cache_file, O_RDONLY);
 634     if (fd == -1)
 635         goto bail;
 636
 637     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 638     if (current_arch_start < 0)
 639         goto bail1;
 640
 641     lseek (fd, current_arch_start, SEEK_SET);
 642     if (FcCacheReadString (fd, candidate_arch_machine_name,
 643                            sizeof (candidate_arch_machine_name)) == 0)
 644         goto bail1;
 645
 646     while (strlen(FcCacheReadString (fd, subdirName, sizeof (subdirName))) > 0)
 647         FcStrSetAdd (dirs, (FcChar8 *)subdirName);
 648
 649     if (!FcDirCacheConsume (fd, set))
 650         goto bail1;
 651
 652     close(fd);
 653     free (cache_file);
 654     return FcTrue;
 655
 656  bail1:
 657     close (fd);
 658  bail:
 659     free (cache_file);
 660     return FcFalse;
 661 }
 662
 663 static FcBool
 664 FcDirCacheConsume (int fd, FcFontSet *set)
 665 {
 666     FcCache metadata;
 667     void * current_dir_block;
 668     off_t pos;
 669
 670     read(fd, &metadata, sizeof(FcCache));
 671     if (metadata.magic != FC_CACHE_MAGIC)
 672         return FcFalse;
 673
 674     if (!metadata.count)
 675         return FcTrue;
 676
 677     pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
 678     current_dir_block = mmap (0, metadata.count,
 679                               PROT_READ, MAP_SHARED, fd, pos);
 680     if (current_dir_block == MAP_FAILED)
 681         return FcFalse;
 682
 683     if (!FcFontSetUnserialize (metadata, set, current_dir_block))
 684         return FcFalse;
 685
 686     return FcTrue;
 687 }
 688
 689 static void *
 690 FcDirCacheProduce (FcFontSet *set, FcCache *metadata)
 691 {
 692     void * current_dir_block, * final_dir_block;
 693     static unsigned int rand_state = 0;
 694     int bank;
 695
 696     if (!rand_state)
 697         rand_state = time(0L);
 698     bank = rand_r(&rand_state);
 699
 700     while (FcCacheHaveBank(bank))
 701         bank = rand_r(&rand_state);
 702
 703     memset (metadata, 0, sizeof(FcCache));
 704     FcFontSetNewBank();
 705     metadata->count = FcFontSetNeededBytes (set);
 706     metadata->magic = FC_CACHE_MAGIC;
 707     metadata->bank = bank;
 708
 709     if (!metadata->count) /* not a failure, no fonts to write */
 710         return 0;
 711
 712     current_dir_block = malloc (metadata->count);
 713     if (!current_dir_block)
 714         goto bail;
 715     final_dir_block = FcFontSetDistributeBytes (metadata, current_dir_block);
 716
 717     if ((char *)current_dir_block + metadata->count != final_dir_block)
 718         goto bail;
 719
 720     if (!FcFontSetSerialize (bank, set))
 721         goto bail;
 722
 723     return current_dir_block;
 724
 725  bail:
 726     free (current_dir_block);
 727     return 0;
 728 }
 729
 730 /* write serialized state to the cache file */
 731 FcBool
 732 FcDirCacheWrite (FcFontSet *set, FcStrSet *dirs, const FcChar8 *dir)
 733 {
 734     FcChar8         *cache_file = FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 735     int fd, i;
 736     FcCache metadata;
 737     off_t current_arch_start = 0, truncate_to;
 738
 739     char * current_arch_machine_name, * header;
 740     void * current_dir_block;
 741
 742     if (!cache_file)
 743         goto bail;
 744
 745     current_dir_block = FcDirCacheProduce (set, &metadata);
 746
 747     if (!metadata.count && !dirs->size)
 748     {
 749         unlink ((char *)cache_file);
 750         free (cache_file);
 751         return FcTrue;
 752     }
 753
 754     if (metadata.count && !current_dir_block)
 755         goto bail;
 756
 757     if (FcDebug () & FC_DBG_CACHE)
 758         printf ("FcDirCacheWriteDir cache_file \"%s\"\n", cache_file);
 759
 760     fd = open((char *)cache_file, O_RDWR | O_CREAT, 0666);
 761     if (fd == -1)
 762         goto bail0;
 763
 764     current_arch_machine_name = FcCacheMachineSignature ();
 765     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 766     if (current_arch_start < 0)
 767         current_arch_start = FcCacheNextOffset (lseek(fd, 0, SEEK_END));
 768
 769     if (!FcCacheMoveDown(fd, current_arch_start))
 770         goto bail0;
 771
 772     current_arch_start = lseek(fd, 0, SEEK_CUR);
 773     if (ftruncate (fd, current_arch_start) == -1)
 774         goto bail0;
 775
 776     /* now write the address of the next offset */
 777     truncate_to = FcCacheNextOffset (FcCacheNextOffset (current_arch_start + sizeof (FcCache)) + metadata.count) - current_arch_start;
 778     header = malloc (10 + strlen (current_arch_machine_name));
 779     if (!header)
 780         goto bail0;
 781     sprintf (header, "%8x ", (int)truncate_to);
 782     strcat (header, current_arch_machine_name);
 783     if (!FcCacheWriteString (fd, header))
 784         goto bail1;
 785
 786     for (i = 0; i < dirs->size; i++)
 787         FcCacheWriteString (fd, (char *)dirs->strs[i]);
 788     FcCacheWriteString (fd, "");
 789
 790     write (fd, &metadata, sizeof(FcCache));
 791     if (metadata.count)
 792     {
 793         lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_END)), SEEK_SET);
 794         write (fd, current_dir_block, metadata.count);
 795         free (current_dir_block);
 796     }
 797
 798     /* this actually serves to pad out the cache file, if needed */
 799     if (ftruncate (fd, current_arch_start + truncate_to) == -1)
 800         goto bail1;
 801
 802     close(fd);
 803     return FcTrue;
 804
 805  bail1:
 806     free (header);
 807  bail0:
 808     free (current_dir_block);
 809  bail:
 810     unlink ((char *)cache_file);
 811     free (cache_file);
 812     return FcFalse;
 813 }
 814
 815 static char *
 816 FcCacheMachineSignature ()
 817 {
 818     static char buf[MACHINE_SIGNATURE_SIZE];
 819     int magic = ENDIAN_TEST;
 820     char * m = (char *)&magic;
 821
 822     sprintf (buf, "%2x%2x%2x%2x "
 823              "%4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x "
 824              "%4x %4x %4x %4x %4x %4x %4x\n",
 825              m[0], m[1], m[2], m[3],
 826              sizeof (char),
 827              sizeof (char *),
 828              sizeof (int),
 829              sizeof (FcPattern),
 830              sizeof (FcPatternEltPtr),
 831              sizeof (struct _FcPatternElt *),
 832              sizeof (FcPatternElt),
 833              sizeof (FcObjectPtr),
 834              sizeof (FcValueListPtr),
 835              sizeof (FcValue),
 836              sizeof (FcValueBinding),
 837              sizeof (struct _FcValueList *),
 838              sizeof (FcCharSet),
 839              sizeof (FcCharLeaf **),
 840              sizeof (FcChar16 *),
 841              sizeof (FcChar16),
 842              sizeof (FcCharLeaf),
 843              sizeof (FcChar32),
 844              sizeof (FcCache));
 845
 846     return buf;
 847 }
 848
 849 static int banks_ptr = 0, banks_alloc = 0;
 850 static int * bankId = 0;
 851
 852 static FcBool
 853 FcCacheHaveBank (int bank)
 854 {
 855     int i;
 856
 857     if (bank < FC_BANK_FIRST)
 858         return FcTrue;
 859
 860     for (i = 0; i < banks_ptr; i++)
 861         if (bankId[i] == bank)
 862             return FcTrue;
 863
 864     return FcFalse;
 865 }
 866
 867 int
 868 FcCacheBankToIndex (int bank)
 869 {
 870     static int lastBank = FC_BANK_DYNAMIC, lastIndex = -1;
 871     int i;
 872     int * b;
 873
 874     if (bank == lastBank)
 875         return lastIndex;
 876
 877     for (i = 0; i < banks_ptr; i++)
 878         if (bankId[i] == bank)
 879             return i;
 880
 881     if (banks_ptr >= banks_alloc)
 882     {
 883         b = realloc (bankId, (banks_alloc + 4) * sizeof(int));
 884         if (!b)
 885             return -1;
 886
 887         bankId = b;
 888         banks_alloc += 4;
 889     }
 890
 891     i = banks_ptr++;
 892     bankId[i] = bank;
 893     return i;
 894 }