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 FcCacheCopyOld (int fd, int fd_orig, 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, fd_orig;
 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         return FcFalse;
 312
 313     if (!FcAtomicLock (atomic))
 314         goto bail1;
 315     fd = open ((char *) FcAtomicNewFile(atomic), O_RDWR | O_CREAT,
 316                S_IRUSR | S_IWUSR);
 317     if (fd == -1)
 318         goto bail2;
 319
 320     fd_orig = open ((char *) FcAtomicOrigFile(atomic), O_RDONLY);
 321
 322     current_arch_machine_name = FcCacheMachineSignature ();
 323     if (fd_orig == -1)
 324         current_arch_start = 0;
 325     else
 326         current_arch_start = FcCacheSkipToArch (fd_orig,
 327                                                 current_arch_machine_name);
 328
 329     if (current_arch_start < 0)
 330         current_arch_start = FcCacheNextOffset (lseek(fd_orig, 0, SEEK_END));
 331
 332     if (!FcCacheCopyOld(fd, fd_orig, current_arch_start))
 333         goto bail3;
 334
 335     close (fd_orig);
 336     fd_orig = -1;
 337
 338     current_arch_start = lseek(fd, 0, SEEK_CUR);
 339     if (ftruncate (fd, current_arch_start) == -1)
 340         goto bail3;
 341
 342     header = malloc (10 + strlen (current_arch_machine_name));
 343     if (!header)
 344         goto bail3;
 345
 346     truncate_to = current_arch_start + strlen(current_arch_machine_name) + 11;
 347     for (dir = cache->dirs; dir; dir = dir->next)
 348     {
 349         truncate_to += strlen(dir->name) + 1;
 350         truncate_to += sizeof (FcCache);
 351         truncate_to = FcCacheNextOffset (current_arch_start + truncate_to);
 352         truncate_to += dir->metadata.count;
 353     }
 354     truncate_to -= current_arch_start;
 355
 356     sprintf (header, "%8x ", (int)truncate_to);
 357     strcat (header, current_arch_machine_name);
 358     if (!FcCacheWriteString (fd, header))
 359         goto bail4;
 360
 361     for (dir = cache->dirs; dir; dir = dir->next)
 362     {
 363         if (dir->ent)
 364         {
 365             FcCacheWriteString (fd, dir->name);
 366             write (fd, &dir->metadata, sizeof(FcCache));
 367             lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_CUR)), SEEK_SET);
 368             write (fd, dir->ent, dir->metadata.count);
 369             free (dir->ent);
 370         }
 371     }
 372     FcCacheWriteString (fd, "");
 373
 374     if (close (fd) == -1)
 375         goto bail25;
 376
 377     if (!FcAtomicReplaceOrig (atomic))
 378         goto bail25;
 379
 380     FcAtomicUnlock (atomic);
 381     FcAtomicDestroy (atomic);
 382
 383     cache->updated = FcFalse;
 384     return FcTrue;
 385
 386  bail4:
 387     free (header);
 388  bail3:
 389     if (fd_orig != -1)
 390         close (fd_orig);
 391
 392     close (fd);
 393  bail25:
 394     FcAtomicDeleteNew (atomic);
 395  bail2:
 396     FcAtomicUnlock (atomic);
 397  bail1:
 398     FcAtomicDestroy (atomic);
 399     return FcFalse;
 400 }
 401
 402 #define PAGESIZE 8192
 403 /*
 404  * Find the next presumably-mmapable offset after the supplied file
 405  * position.
 406  */
 407 static int
 408 FcCacheNextOffset(off_t w)
 409 {
 410     if (w % PAGESIZE == 0)
 411         return w;
 412     else
 413         return ((w / PAGESIZE)+1)*PAGESIZE;
 414 }
 415
 416 /* return the address of the segment for the provided arch,
 417  * or -1 if arch not found */
 418 static off_t
 419 FcCacheSkipToArch (int fd, const char * arch)
 420 {
 421     char candidate_arch_machine_name_count[MACHINE_SIGNATURE_SIZE + 9];
 422     char * candidate_arch;
 423     off_t current_arch_start = 0;
 424
 425     /* skip arches that are not the current arch */
 426     while (1)
 427     {
 428         long bs;
 429
 430         if (lseek (fd, current_arch_start, SEEK_SET) != current_arch_start)
 431             return -1;
 432
 433         if (FcCacheReadString (fd, candidate_arch_machine_name_count,
 434                                 sizeof (candidate_arch_machine_name_count)) == 0)
 435             return -1;
 436         if (!strlen(candidate_arch_machine_name_count))
 437             return -1;
 438         bs = strtol(candidate_arch_machine_name_count, &candidate_arch, 16);
 439
 440         // count = 0 should probably be distinguished from the !bs condition
 441         if (!bs || bs < strlen (candidate_arch_machine_name_count))
 442             return -1;
 443
 444         candidate_arch++; /* skip leading space */
 445
 446         if (strcmp (candidate_arch, arch)==0)
 447             return current_arch_start;
 448         current_arch_start += bs;
 449     }
 450
 451     return -1;
 452 }
 453
 454 /* Cuts out the segment at the file pointer (moves everything else
 455  * down to cover it), and leaves the file pointer at the end of the
 456  * file. */
 457 static FcBool
 458 FcCacheCopyOld (int fd, int fd_orig, off_t start)
 459 {
 460     char * buf = malloc (8192);
 461     char candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
 462     long bs;
 463     int c, bytes_skipped;
 464     off_t loc;
 465
 466     if (!buf)
 467         return FcFalse;
 468
 469     loc = 0;
 470     lseek (fd, 0, SEEK_SET); lseek (fd_orig, 0, SEEK_SET);
 471     do
 472     {
 473         int b = 8192;
 474         if (loc + b > start)
 475             b = start - loc;
 476
 477         if ((c = read (fd_orig, buf, b)) <= 0)
 478             break;
 479         if (write (fd, buf, c) < 0)
 480             goto bail;
 481
 482         loc += c;
 483     }
 484     while (c > 0);
 485
 486     lseek (fd, start, SEEK_SET);
 487     if (FcCacheReadString (fd, candidate_arch_machine_name,
 488                            sizeof (candidate_arch_machine_name)) == 0)
 489         goto done;
 490     if (!strlen(candidate_arch_machine_name))
 491         goto done;
 492
 493     bs = strtol(candidate_arch_machine_name, 0, 16);
 494     if (bs == 0)
 495         goto done;
 496
 497     bytes_skipped = 0;
 498     do
 499     {
 500         lseek (fd, start+bs+bytes_skipped, SEEK_SET);
 501         if ((c = read (fd, buf, 8192)) <= 0)
 502             break;
 503         lseek (fd, start+bytes_skipped, SEEK_SET);
 504         if (write (fd, buf, c) < 0)
 505             goto bail;
 506         bytes_skipped += c;
 507     }
 508     while (c > 0);
 509     lseek (fd, start+bytes_skipped, SEEK_SET);
 510
 511  done:
 512     free (buf);
 513     return FcTrue;
 514
 515  bail:
 516     free (buf);
 517     return FcFalse;
 518 }
 519
 520 FcBool
 521 FcDirCacheValid (const FcChar8 *dir)
 522 {
 523     FcChar8     *cache_file = FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 524     struct stat file_stat, dir_stat;
 525     int         fd;
 526     off_t       current_arch_start;
 527     char        *current_arch_machine_name;
 528
 529     if (stat ((char *) dir, &dir_stat) < 0)
 530     {
 531         FcStrFree (cache_file);
 532         return FcFalse;
 533     }
 534     if (stat ((char *) cache_file, &file_stat) < 0)
 535     {
 536         FcStrFree (cache_file);
 537         return FcFalse;
 538     }
 539
 540     current_arch_machine_name = FcCacheMachineSignature();
 541     fd = open(cache_file, O_RDONLY);
 542     if (fd == -1)
 543         return FcFalse;
 544
 545     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 546     close (fd);
 547
 548     if (current_arch_start < 0)
 549         return FcFalse;
 550
 551     FcStrFree (cache_file);
 552     /*
 553      * If the directory has been modified more recently than
 554      * the cache file, the cache is not valid
 555      */
 556     if (dir_stat.st_mtime - file_stat.st_mtime > 0)
 557         return FcFalse;
 558     return FcTrue;
 559 }
 560
 561 static int
 562 FcCacheReadDirs (FcConfig * config, FcGlobalCache * cache,
 563                  FcStrList *list, FcFontSet * set)
 564 {
 565     int                 ret = 0;
 566     FcChar8             *dir;
 567     FcChar8             *file, *base;
 568     FcStrSet            *subdirs;
 569     FcStrList           *sublist;
 570     struct stat         statb;
 571
 572     /*
 573      * Read in the results from 'list'.
 574      */
 575     while ((dir = FcStrListNext (list)))
 576     {
 577         /* freed below */
 578         file = (FcChar8 *) malloc (strlen ((char *) dir) + 1 + FC_MAX_FILE_LEN + 1);
 579         if (!file)
 580             return FcFalse;
 581
 582         strcpy ((char *) file, (char *) dir);
 583         strcat ((char *) file, "/");
 584         base = file + strlen ((char *) file);
 585
 586         subdirs = FcStrSetCreate ();
 587         if (!subdirs)
 588         {
 589             fprintf (stderr, "Can't create directory set\n");
 590             ret++;
 591             free (file);
 592             continue;
 593         }
 594
 595         if (access ((char *) dir, X_OK) < 0)
 596         {
 597             switch (errno) {
 598             case ENOENT:
 599             case ENOTDIR:
 600             case EACCES:
 601                 break;
 602             default:
 603                 fprintf (stderr, "\"%s\": ", dir);
 604                 perror ("");
 605                 ret++;
 606             }
 607             FcStrSetDestroy (subdirs);
 608             free (file);
 609             continue;
 610         }
 611         if (stat ((char *) dir, &statb) == -1)
 612         {
 613             fprintf (stderr, "\"%s\": ", dir);
 614             perror ("");
 615             FcStrSetDestroy (subdirs);
 616             ret++;
 617             free (file);
 618             continue;
 619         }
 620         if (!S_ISDIR (statb.st_mode))
 621         {
 622             fprintf (stderr, "\"%s\": not a directory, skipping\n", dir);
 623             FcStrSetDestroy (subdirs);
 624             free (file);
 625             continue;
 626         }
 627         if (!FcDirCacheValid (dir) || !FcDirCacheRead (set, subdirs, dir))
 628         {
 629             if (FcDebug () & FC_DBG_FONTSET)
 630                 printf ("cache scan dir %s\n", dir);
 631
 632             FcDirScanConfig (set, subdirs, cache,
 633                              config->blanks, dir, FcFalse, config);
 634         }
 635         sublist = FcStrListCreate (subdirs);
 636         FcStrSetDestroy (subdirs);
 637         if (!sublist)
 638         {
 639             fprintf (stderr, "Can't create subdir list in \"%s\"\n", dir);
 640             ret++;
 641             free (file);
 642             continue;
 643         }
 644         ret += FcCacheReadDirs (config, cache, sublist, set);
 645         free (file);
 646     }
 647     FcStrListDone (list);
 648     return ret;
 649 }
 650
 651 FcFontSet *
 652 FcCacheRead (FcConfig *config, FcGlobalCache * cache)
 653 {
 654     FcFontSet * s = FcFontSetCreate();
 655     if (!s)
 656         return 0;
 657
 658     if (FcCacheReadDirs (config, cache, FcConfigGetConfigDirs (config), s))
 659         goto bail;
 660
 661     return s;
 662
 663  bail:
 664     FcFontSetDestroy (s);
 665     return 0;
 666 }
 667
 668 /* read serialized state from the cache file */
 669 static FcBool
 670 FcDirCacheRead (FcFontSet * set, FcStrSet * dirs, const FcChar8 *dir)
 671 {
 672     char *cache_file = (char *)FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 673     int fd;
 674     char * current_arch_machine_name;
 675     char candidate_arch_machine_name[9+MACHINE_SIGNATURE_SIZE];
 676     off_t current_arch_start = 0;
 677     char subdirName[FC_MAX_FILE_LEN + 1 + 12 + 1];
 678
 679     if (!cache_file)
 680         goto bail;
 681
 682     current_arch_machine_name = FcCacheMachineSignature();
 683     fd = open(cache_file, O_RDONLY);
 684     if (fd == -1)
 685         goto bail;
 686
 687     current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
 688     if (current_arch_start < 0)
 689         goto bail1;
 690
 691     lseek (fd, current_arch_start, SEEK_SET);
 692     if (FcCacheReadString (fd, candidate_arch_machine_name,
 693                            sizeof (candidate_arch_machine_name)) == 0)
 694         goto bail1;
 695
 696     while (strlen(FcCacheReadString (fd, subdirName, sizeof (subdirName))) > 0)
 697         FcStrSetAdd (dirs, (FcChar8 *)subdirName);
 698
 699     if (!FcDirCacheConsume (fd, set))
 700         goto bail1;
 701
 702     close(fd);
 703     free (cache_file);
 704     return FcTrue;
 705
 706  bail1:
 707     close (fd);
 708  bail:
 709     free (cache_file);
 710     return FcFalse;
 711 }
 712
 713 static FcBool
 714 FcDirCacheConsume (int fd, FcFontSet *set)
 715 {
 716     FcCache metadata;
 717     void * current_dir_block;
 718     off_t pos;
 719
 720     read(fd, &metadata, sizeof(FcCache));
 721     if (metadata.magic != FC_CACHE_MAGIC)
 722         return FcFalse;
 723
 724     if (!metadata.count)
 725         return FcTrue;
 726
 727     pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
 728     current_dir_block = mmap (0, metadata.count,
 729                               PROT_READ, MAP_SHARED, fd, pos);
 730     if (current_dir_block == MAP_FAILED)
 731         return FcFalse;
 732
 733     if (!FcFontSetUnserialize (metadata, set, current_dir_block))
 734         return FcFalse;
 735
 736     return FcTrue;
 737 }
 738
 739 static void *
 740 FcDirCacheProduce (FcFontSet *set, FcCache *metadata)
 741 {
 742     void * current_dir_block, * final_dir_block;
 743     static unsigned int rand_state = 0;
 744     int bank;
 745
 746     if (!rand_state)
 747         rand_state = time(0L);
 748     bank = rand_r(&rand_state);
 749
 750     while (FcCacheHaveBank(bank))
 751         bank = rand_r(&rand_state);
 752
 753     memset (metadata, 0, sizeof(FcCache));
 754     FcFontSetNewBank();
 755     metadata->count = FcFontSetNeededBytes (set);
 756     metadata->magic = FC_CACHE_MAGIC;
 757     metadata->bank = bank;
 758
 759     if (!metadata->count) /* not a failure, no fonts to write */
 760         return 0;
 761
 762     current_dir_block = malloc (metadata->count);
 763     if (!current_dir_block)
 764         goto bail;
 765     final_dir_block = FcFontSetDistributeBytes (metadata, current_dir_block);
 766
 767     if ((char *)current_dir_block + metadata->count != final_dir_block)
 768         goto bail;
 769
 770     if (!FcFontSetSerialize (bank, set))
 771         goto bail;
 772
 773     return current_dir_block;
 774
 775  bail:
 776     free (current_dir_block);
 777     return 0;
 778 }
 779
 780 /* write serialized state to the cache file */
 781 FcBool
 782 FcDirCacheWrite (FcFontSet *set, FcStrSet *dirs, const FcChar8 *dir)
 783 {
 784     FcChar8         *cache_file = FcStrPlus (dir, (FcChar8 *) "/" FC_DIR_CACHE_FILE);
 785     int             fd, fd_orig, i, dirs_count;
 786     FcAtomic        *atomic;
 787     FcCache         metadata;
 788     off_t           current_arch_start = 0, truncate_to;
 789
 790     char            *current_arch_machine_name, * header;
 791     void            *current_dir_block;
 792
 793     if (!cache_file)
 794         goto bail;
 795
 796     current_dir_block = FcDirCacheProduce (set, &metadata);
 797
 798     if (metadata.count && !current_dir_block)
 799         goto bail0;
 800
 801     if (FcDebug () & FC_DBG_CACHE)
 802         printf ("FcDirCacheWriteDir cache_file \"%s\"\n", cache_file);
 803
 804     atomic = FcAtomicCreate (cache_file);
 805     if (!atomic)
 806         goto bail0;
 807
 808     if (!FcAtomicLock (atomic))
 809         goto bail1;
 810
 811     fd_orig = open((char *)FcAtomicOrigFile (atomic), O_RDONLY, 0666);
 812
 813     fd = open((char *)FcAtomicNewFile (atomic), O_RDWR | O_CREAT, 0666);
 814     if (fd == -1)
 815         goto bail2;
 816
 817     current_arch_machine_name = FcCacheMachineSignature ();
 818     current_arch_start = 0;
 819
 820     if (fd_orig != -1)
 821         current_arch_start =
 822             FcCacheSkipToArch(fd_orig, current_arch_machine_name);
 823
 824     if (current_arch_start < 0)
 825         current_arch_start = FcCacheNextOffset (lseek(fd_orig, 0, SEEK_END));
 826
 827     if (fd_orig != -1 && !FcCacheCopyOld(fd, fd_orig, current_arch_start))
 828         goto bail3;
 829
 830     if (fd_orig != -1)
 831         close (fd_orig);
 832
 833     current_arch_start = lseek(fd, 0, SEEK_CUR);
 834     if (ftruncate (fd, current_arch_start) == -1)
 835         goto bail3;
 836
 837     /* allocate space for subdir names in this block */
 838     dirs_count = 0;
 839     for (i = 0; i < dirs->size; i++)
 840         dirs_count += strlen((char *)dirs->strs[i]) + 1;
 841     dirs_count ++;
 842
 843     /* now write the address of the next offset */
 844     truncate_to = FcCacheNextOffset (FcCacheNextOffset (current_arch_start + sizeof (FcCache) + dirs_count) + metadata.count) - current_arch_start;
 845     header = malloc (10 + strlen (current_arch_machine_name));
 846     if (!header)
 847         goto bail3;
 848     sprintf (header, "%8x ", (int)truncate_to);
 849     strcat (header, current_arch_machine_name);
 850     if (!FcCacheWriteString (fd, header))
 851         goto bail4;
 852
 853     for (i = 0; i < dirs->size; i++)
 854         FcCacheWriteString (fd, (char *)dirs->strs[i]);
 855     FcCacheWriteString (fd, "");
 856
 857     write (fd, &metadata, sizeof(FcCache));
 858     if (metadata.count)
 859     {
 860         lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_END)), SEEK_SET);
 861         write (fd, current_dir_block, metadata.count);
 862         free (current_dir_block);
 863     }
 864
 865     /* this actually serves to pad out the cache file, if needed */
 866     if (ftruncate (fd, current_arch_start + truncate_to) == -1)
 867         goto bail4;
 868
 869     close(fd);
 870     if (!FcAtomicReplaceOrig(atomic))
 871         goto bail4;
 872     FcAtomicUnlock (atomic);
 873     FcAtomicDestroy (atomic);
 874     return FcTrue;
 875
 876  bail4:
 877     free (header);
 878  bail3:
 879     close (fd);
 880  bail2:
 881     FcAtomicUnlock (atomic);
 882  bail1:
 883     FcAtomicDestroy (atomic);
 884  bail0:
 885     unlink ((char *)cache_file);
 886     free (cache_file);
 887     if (current_dir_block)
 888         free (current_dir_block);
 889  bail:
 890     return FcFalse;
 891 }
 892
 893 static char *
 894 FcCacheMachineSignature ()
 895 {
 896     static char buf[MACHINE_SIGNATURE_SIZE];
 897     int magic = ENDIAN_TEST;
 898     char * m = (char *)&magic;
 899
 900     sprintf (buf, "%2x%2x%2x%2x "
 901              "%4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x "
 902              "%4x %4x %4x %4x %4x %4x %4x\n",
 903              m[0], m[1], m[2], m[3],
 904              (unsigned int)sizeof (char),
 905              (unsigned int)sizeof (char *),
 906              (unsigned int)sizeof (int),
 907              (unsigned int)sizeof (FcPattern),
 908              (unsigned int)sizeof (FcPatternEltPtr),
 909              (unsigned int)sizeof (struct _FcPatternElt *),
 910              (unsigned int)sizeof (FcPatternElt),
 911              (unsigned int)sizeof (FcObjectPtr),
 912              (unsigned int)sizeof (FcValueListPtr),
 913              (unsigned int)sizeof (FcValue),
 914              (unsigned int)sizeof (FcValueBinding),
 915              (unsigned int)sizeof (struct _FcValueList *),
 916              (unsigned int)sizeof (FcCharSet),
 917              (unsigned int)sizeof (FcCharLeaf **),
 918              (unsigned int)sizeof (FcChar16 *),
 919              (unsigned int)sizeof (FcChar16),
 920              (unsigned int)sizeof (FcCharLeaf),
 921              (unsigned int)sizeof (FcChar32),
 922              (unsigned int)sizeof (FcCache));
 923
 924     return buf;
 925 }
 926
 927 static int banks_ptr = 0, banks_alloc = 0;
 928 static int * bankId = 0;
 929
 930 static FcBool
 931 FcCacheHaveBank (int bank)
 932 {
 933     int i;
 934
 935     if (bank < FC_BANK_FIRST)
 936         return FcTrue;
 937
 938     for (i = 0; i < banks_ptr; i++)
 939         if (bankId[i] == bank)
 940             return FcTrue;
 941
 942     return FcFalse;
 943 }
 944
 945 int
 946 FcCacheBankToIndex (int bank)
 947 {
 948     static int lastBank = FC_BANK_DYNAMIC, lastIndex = -1;
 949     int i;
 950     int * b;
 951
 952     if (bank == lastBank)
 953         return lastIndex;
 954
 955     for (i = 0; i < banks_ptr; i++)
 956         if (bankId[i] == bank)
 957             return i;
 958
 959     if (banks_ptr >= banks_alloc)
 960     {
 961         b = realloc (bankId, (banks_alloc + 4) * sizeof(int));
 962         if (!b)
 963             return -1;
 964
 965         bankId = b;
 966         banks_alloc += 4;
 967     }
 968
 969     i = banks_ptr++;
 970     bankId[i] = bank;
 971     return i;
 972 }