hcache.c

   1 /*
   2  * Copyright (C) 2004 Thomas Glanzmann <sithglan@stud.uni-erlangen.de>
   3  * Copyright (C) 2004 Tobias Werth <sitowert@stud.uni-erlangen.de>
   4  * Copyright (C) 2004 Brian Fundakowski Feldman <green@FreeBSD.org>
   5  *
   6  *     This program is free software; you can redistribute it and/or modify
   7  *     it under the terms of the GNU General Public License as published by
   8  *     the Free Software Foundation; either version 2 of the License, or
   9  *     (at your option) any later version.
  10  *
  11  *     This program is distributed in the hope that it will be useful,
  12  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *     GNU General Public License for more details.
  15  *
  16  *     You should have received a copy of the GNU General Public License
  17  *     along with this program; if not, write to the Free Software
  18  *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  19  */
  20
  21 # if HAVE_INTTYPES_H
  22 #  include <inttypes.h>
  23 # else
  24 #  if HAVE_STDINT_H
  25 #   include <stdint.h>
  26 #  endif
  27 # endif
  28
  29 #if HAVE_CONFIG_H
  30 #include "config.h"
  31 #endif                          /* HAVE_CONFIG_H */
  32
  33 #ifdef USE_HCACHE
  34
  35 #if HAVE_GDBM
  36 #include <gdbm.h>
  37 #elif HAVE_DB4
  38 #include <db.h>
  39 #endif
  40
  41 #include <errno.h>
  42 #include <fcntl.h>
  43 #include "mutt.h"
  44 #ifdef USE_IMAP
  45 #include "message.h"
  46 #endif
  47 #include "mime.h"
  48 #include "mx.h"
  49 #include "lib.h"
  50 #include "md5.h"
  51
  52 #if HAVE_GDBM
  53 static struct
  54 header_cache
  55 {
  56         GDBM_FILE db;
  57         char *folder;
  58         unsigned int crc;
  59 } HEADER_CACHE;
  60 #elif HAVE_DB4
  61 static struct
  62 header_cache
  63 {
  64         DB_ENV *env;
  65         DB *db;
  66         unsigned int crc;
  67         int fd;
  68         char lockfile[_POSIX_PATH_MAX];
  69 } HEADER_CACHE;
  70 #endif
  71
  72 typedef union
  73 {
  74         struct timeval timeval;
  75         uint64_t uid_validity;
  76 } validate;
  77
  78 static void *
  79 lazy_malloc(size_t siz)
  80 {
  81         if (0 < siz && siz < 4096) {
  82                 siz = 4096;
  83         }
  84
  85         return safe_malloc(siz);
  86 }
  87
  88 static void
  89 lazy_realloc(void *ptr, size_t siz)
  90 {
  91         void **p = (void **)ptr;
  92
  93         if ( p != NULL
  94         &&   0 < siz
  95         && siz < 4096) {
  96                 return;
  97         }
  98
  99         safe_realloc(ptr, siz);
 100 }
 101
 102 static unsigned char *
 103 dump_int(unsigned int i, unsigned char *d, int *off)
 104 {
 105         lazy_realloc(&d, *off + sizeof(int));
 106         memcpy(d + *off, &i, sizeof(int));
 107         (*off) += sizeof(int);
 108
 109         return d;
 110 }
 111
 112 static void
 113 restore_int(unsigned int *i, const unsigned char *d, int *off)
 114 {
 115         memcpy(i, d + *off, sizeof(int));
 116         (*off) += sizeof(int);
 117 }
 118
 119 static unsigned char *
 120 dump_char(char *c, unsigned char *d, int *off)
 121 {
 122         unsigned int size;
 123
 124         if (c == NULL) {
 125                 size = 0;
 126                 d = dump_int(size, d, off);
 127                 return d;
 128         }
 129
 130         size = mutt_strlen(c) + 1;
 131         d = dump_int(size, d, off);
 132         lazy_realloc(&d, *off + size);
 133         memcpy(d + *off, c, size);
 134         *off += size;
 135
 136         return d;
 137 }
 138
 139 static unsigned char *
 140 dump_char_size(char *c, unsigned char *d, int *off, ssize_t size)
 141 {
 142         if (c == NULL) {
 143                 size = 0;
 144                 d = dump_int(size, d, off);
 145                 return d;
 146         }
 147
 148         d = dump_int(size, d, off);
 149         lazy_realloc(&d, *off + size);
 150         memcpy(d + *off, c, size);
 151         *off += size;
 152
 153         return d;
 154 }
 155
 156 static void
 157 restore_char(char **c, const unsigned char *d, int *off)
 158 {
 159         unsigned int size;
 160         restore_int(&size, d, off);
 161
 162         if (size == 0) {
 163                 *c = NULL;
 164                 return;
 165         }
 166
 167         *c = safe_malloc(size);
 168         memcpy(*c, d + *off, size);
 169         *off += size;
 170 }
 171
 172 static unsigned char *
 173 dump_address(ADDRESS *a, unsigned char *d, int *off)
 174 {
 175         unsigned int counter = 0;
 176         unsigned int start_off = *off;
 177
 178         d = dump_int(0xdeadbeef, d, off);
 179
 180         while (a) {
 181 #ifdef EXACT_ADDRESS
 182                 d = dump_char(a->val, d, off);
 183 #endif
 184                 d = dump_char(a->personal, d, off);
 185                 d = dump_char(a->mailbox, d, off);
 186                 d = dump_int(a->group, d, off);
 187                 a = a->next;
 188                 counter++;
 189         }
 190
 191         memcpy(d + start_off, &counter, sizeof(int));
 192
 193         return d;
 194 }
 195
 196 static void
 197 restore_address(ADDRESS **a, const unsigned char *d, int *off)
 198 {
 199         unsigned int counter;
 200
 201         restore_int(&counter, d, off);
 202
 203         while (counter) {
 204                 *a = safe_malloc(sizeof(ADDRESS));
 205 #ifdef EXACT_ADDRESS
 206                 restore_char(&(*a)->val, d, off);
 207 #endif
 208                 restore_char(&(*a)->personal, d, off);
 209                 restore_char(&(*a)->mailbox, d, off);
 210                 restore_int((unsigned int *)&(*a)->group, d, off);
 211                 a = &(*a)->next;
 212                 counter--;
 213         }
 214
 215         *a = NULL;
 216 }
 217
 218 static unsigned char *
 219 dump_list(LIST *l, unsigned char *d, int *off)
 220 {
 221         unsigned int counter = 0;
 222         unsigned int start_off = *off;
 223
 224         d = dump_int(0xdeadbeef, d, off);
 225
 226         while (l) {
 227                 d = dump_char(l->data, d, off);
 228                 l = l->next;
 229                 counter++;
 230         }
 231
 232         memcpy(d + start_off, &counter, sizeof(int));
 233
 234         return d;
 235 }
 236
 237 static void
 238 restore_list(LIST **l, const unsigned char *d, int *off)
 239 {
 240         unsigned int counter;
 241
 242         restore_int(&counter, d, off);
 243
 244         while (counter) {
 245                 *l = safe_malloc(sizeof(LIST));
 246                 restore_char(&(*l)->data, d, off);
 247                 l = &(*l)->next;
 248                 counter--;
 249         }
 250
 251         *l = NULL;
 252 }
 253
 254 static unsigned char *
 255 dump_buffer(BUFFER *b, unsigned char *d, int *off)
 256 {
 257         if (! b) {
 258                 d = dump_int(0, d, off);
 259                 return d;
 260         } else {
 261                 d = dump_int(1, d, off);
 262         }
 263
 264         d = dump_char_size(b->data, d, off, b->dsize + 1);
 265         d = dump_int(b->dptr - b->data, d, off);
 266         d = dump_int(b->dsize, d, off);
 267         d = dump_int(b->destroy, d, off);
 268
 269         return d;
 270 }
 271
 272 static void
 273 restore_buffer(BUFFER **b, const unsigned char *d, int *off)
 274 {
 275         unsigned int used;
 276         unsigned int offset;
 277         restore_int(&used, d, off);
 278         if (! used) {
 279                 return;
 280         }
 281
 282         *b = safe_malloc(sizeof(BUFFER));
 283
 284         restore_char(& (*b)->data, d, off);
 285         restore_int(& offset, d, off);
 286         (*b)->dptr = (*b)->data + offset;
 287         restore_int(& (*b)->dsize, d, off);
 288         restore_int((unsigned int *) & (*b)->destroy, d, off);
 289 }
 290
 291 static unsigned char *
 292 dump_parameter(PARAMETER *p, unsigned char *d, int *off)
 293 {
 294         unsigned int counter = 0;
 295         unsigned int start_off = *off;
 296
 297         d = dump_int(0xdeadbeef, d, off);
 298
 299         while (p) {
 300                 d = dump_char(p->attribute, d, off);
 301                 d = dump_char(p->value, d, off);
 302                 p = p->next;
 303                 counter++;
 304         }
 305
 306         memcpy(d + start_off, &counter, sizeof(int));
 307
 308         return d;
 309 }
 310
 311 static void
 312 restore_parameter(PARAMETER **p, const unsigned char *d, int *off)
 313 {
 314         unsigned int counter;
 315
 316         restore_int(&counter, d, off);
 317
 318         while (counter) {
 319                 *p = safe_malloc(sizeof(PARAMETER));
 320                 restore_char(&(*p)->attribute, d, off);
 321                 restore_char(&(*p)->value, d, off);
 322                 p = &(*p)->next;
 323                 counter--;
 324         }
 325
 326         *p = NULL;
 327 }
 328
 329 static unsigned char *
 330 dump_body(BODY *c, unsigned char *d, int *off)
 331 {
 332         lazy_realloc(&d, *off + sizeof(BODY));
 333         memcpy(d + *off, c, sizeof(BODY));
 334         *off += sizeof(BODY);
 335
 336         d = dump_char(c->xtype, d, off);
 337         d = dump_char(c->subtype, d, off);
 338
 339         d = dump_parameter(c->parameter, d, off);
 340
 341         d = dump_char(c->description, d, off);
 342         d = dump_char(c->form_name, d, off);
 343         d = dump_char(c->filename, d, off);
 344         d = dump_char(c->d_filename, d, off);
 345
 346         return d;
 347 }
 348
 349 static void
 350 restore_body(BODY *c, const unsigned char *d, int *off)
 351 {
 352         memcpy(c, d + *off, sizeof(BODY));
 353         *off += sizeof(BODY);
 354
 355         restore_char(& c->xtype, d, off);
 356         restore_char(& c->subtype, d, off);
 357
 358         restore_parameter(& c->parameter, d, off);
 359
 360         restore_char(& c->description, d, off);
 361         restore_char(& c->form_name, d, off);
 362         restore_char(& c->filename, d, off);
 363         restore_char(& c->d_filename, d, off);
 364 }
 365
 366 static unsigned char *
 367 dump_envelope(ENVELOPE *e, unsigned char *d, int *off)
 368 {
 369         d = dump_address(e->return_path, d, off);
 370         d = dump_address(e->from, d, off);
 371         d = dump_address(e->to, d, off);
 372         d = dump_address(e->cc, d, off);
 373         d = dump_address(e->bcc, d, off);
 374         d = dump_address(e->sender, d, off);
 375         d = dump_address(e->reply_to, d, off);
 376         d = dump_address(e->mail_followup_to, d, off);
 377
 378         d = dump_char(e->subject, d, off);
 379         if (e->real_subj) {
 380                 d = dump_int(e->real_subj - e->subject, d, off);
 381         } else {
 382                 d = dump_int(-1, d, off);
 383         }
 384         d = dump_char(e->message_id, d, off);
 385         d = dump_char(e->supersedes, d, off);
 386         d = dump_char(e->date, d, off);
 387         d = dump_char(e->x_label, d, off);
 388
 389         d = dump_list(e->references, d, off);
 390         d = dump_list(e->in_reply_to, d, off);
 391         d = dump_list(e->userhdrs, d, off);
 392
 393         return d;
 394 }
 395
 396 static void
 397 restore_envelope(ENVELOPE *e, const unsigned char *d, int *off)
 398 {
 399         int real_subj_off;
 400
 401         restore_address(& e->return_path, d, off);
 402         restore_address(& e->from, d, off);
 403         restore_address(& e->to, d, off);
 404         restore_address(& e->cc, d, off);
 405         restore_address(& e->bcc, d, off);
 406         restore_address(& e->sender, d, off);
 407         restore_address(& e->reply_to, d, off);
 408         restore_address(& e->mail_followup_to, d, off);
 409
 410         restore_char(& e->subject, d, off);
 411         restore_int((unsigned int *) (& real_subj_off), d, off);
 412         if (0 <= real_subj_off) {
 413                 e->real_subj = e->subject + real_subj_off;
 414         } else {
 415                 e->real_subj = NULL;
 416         }
 417         restore_char(& e->message_id, d, off);
 418         restore_char(& e->supersedes, d, off);
 419         restore_char(& e->date, d, off);
 420         restore_char(& e->x_label, d, off);
 421
 422         restore_list(& e->references, d, off);
 423         restore_list(& e->in_reply_to, d, off);
 424         restore_list(& e->userhdrs, d, off);
 425 }
 426
 427 static
 428 unsigned int crc32(unsigned int crc, unsigned char const *p, size_t len)
 429 {
 430         int i;
 431         while (len--) {
 432                 crc ^= *p++;
 433                 for (i = 0; i < 8; i++)
 434                         crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0);
 435         }
 436         return crc;
 437 }
 438
 439 static int
 440 generate_crc32()
 441 {
 442         int crc = 0;
 443
 444         crc = crc32(crc, (unsigned char const *) "sithglan@stud.uni-erlangen.de[sithglan]|hcache.c|20041108231548|29613", mutt_strlen("sithglan@stud.uni-erlangen.de[sithglan]|hcache.c|20041108231548|29613"));
 445
 446 #if HAVE_LANGINFO_CODESET
 447         crc = crc32(crc, (unsigned char const *) Charset, mutt_strlen(Charset));
 448         crc = crc32(crc, (unsigned char const *) "HAVE_LANGINFO_CODESET", mutt_strlen("HAVE_LANGINFO_CODESET"));
 449 #endif
 450
 451 #if EXACT_ADDRESS
 452         crc = crc32(crc, (unsigned char const *) "EXACT_ADDRESS", mutt_strlen("EXACT_ADDRESS"));
 453 #endif
 454
 455 #ifdef USE_POP
 456         crc = crc32(crc, (unsigned char const *) "USE_POP", mutt_strlen("USE_POP"));
 457 #endif
 458
 459 #ifdef MIXMASTER
 460         crc = crc32(crc, (unsigned char const *) "MIXMASTER", mutt_strlen("MIXMASTER"));
 461 #endif
 462
 463 #ifdef USE_IMAP
 464         crc = crc32(crc, (unsigned char const *) "USE_IMAP", mutt_strlen("USE_IMAP"));
 465 #endif
 466         return crc;
 467 }
 468
 469 static int
 470 crc32_matches(const char *d, unsigned int crc)
 471 {
 472         int off = sizeof(validate);
 473         unsigned int mycrc = 0;
 474
 475         if (! d) {
 476                 return 0;
 477         }
 478
 479         restore_int(&mycrc, (unsigned char *) d, &off);
 480
 481         return (crc == mycrc);
 482 }
 483
 484 /* Append md5sumed folder to path if path is a directory. */
 485 static const char *
 486 mutt_hcache_per_folder(const char *path, const char *folder)
 487 {
 488         static char mutt_hcache_per_folder_path[_POSIX_PATH_MAX];
 489         struct stat path_stat;
 490         MD5_CTX md5;
 491         unsigned char md5sum[16];
 492         int ret;
 493
 494         ret = stat(path, &path_stat);
 495         if (ret < 0) {
 496                 return path;
 497         }
 498
 499         if (! S_ISDIR(path_stat.st_mode)) {
 500                 return path;
 501         }
 502
 503         MD5Init(&md5);
 504         MD5Update(&md5, (unsigned char *) folder, strlen(folder));
 505         MD5Final(md5sum, &md5);
 506
 507         ret = snprintf(mutt_hcache_per_folder_path, _POSIX_PATH_MAX,
 508                         "%s/%02x%02x%02x%02x%02x%02x%02x%02x"
 509                         "%02x%02x%02x%02x%02x%02x%02x%02x",
 510                         path, md5sum[0], md5sum[1], md5sum[2], md5sum[3],
 511                         md5sum[4], md5sum[5], md5sum[6], md5sum[7], md5sum[8],
 512                         md5sum[9], md5sum[10], md5sum[11], md5sum[12],
 513                         md5sum[13], md5sum[14], md5sum[15]);
 514
 515         if (ret <= 0) {
 516                 return path;
 517         }
 518
 519         return mutt_hcache_per_folder_path;
 520 }
 521
 522 /* This function transforms a header into a char so that it is useable by
 523  * db_store */
 524 static void *
 525 mutt_hcache_dump(void *_db, HEADER *h, int *off, uint64_t uid_validity)
 526 {
 527         struct header_cache *db = _db;
 528         unsigned char *d = NULL;
 529         *off             = 0;
 530
 531         d = lazy_malloc(sizeof(validate));
 532
 533         if (uid_validity) {
 534                 memcpy(d, &uid_validity, sizeof(uint64_t));
 535         } else {
 536                 struct timeval now;
 537                 gettimeofday(&now, NULL);
 538                 memcpy(d, &now, sizeof(struct timeval));
 539         }
 540         *off += sizeof(validate);
 541
 542         d = dump_int(db->crc, d, off);
 543
 544         lazy_realloc(&d, *off + sizeof(HEADER));
 545         memcpy(d + *off, h, sizeof(HEADER));
 546         *off += sizeof(HEADER);
 547
 548         d = dump_envelope(h->env, d, off);
 549         d = dump_body(h->content, d, off);
 550         d = dump_char(h->maildir_flags, d, off);
 551
 552         return d;
 553 }
 554
 555 HEADER *
 556 mutt_hcache_restore(const unsigned char *d, HEADER **oh)
 557 {
 558         int off = 0;
 559         HEADER *h        = mutt_new_header();
 560
 561         /* skip validate */
 562         off += sizeof(validate);
 563
 564         /* skip crc */
 565         off += sizeof(unsigned int);
 566
 567         memcpy(h, d + off, sizeof(HEADER));
 568         off += sizeof(HEADER);
 569
 570         h->env = mutt_new_envelope();
 571         restore_envelope(h->env, d, &off);
 572
 573         h->content = mutt_new_body();
 574         restore_body(h->content, d, &off);
 575
 576         restore_char(&h->maildir_flags, d, &off);
 577
 578         /* this is needed for maildir style mailboxes */
 579         if (oh) {
 580                 h->old  = (*oh)->old;
 581                 h->path = safe_strdup((*oh)->path);
 582                 mutt_free_header (oh);
 583         }
 584
 585         return h;
 586 }
 587
 588 #if HAVE_GDBM
 589
 590 void *
 591 mutt_hcache_open(const char *path, const char *folder)
 592 {
 593         struct header_cache *h = safe_calloc(1, sizeof(HEADER_CACHE));
 594         int pagesize = atoi(HeaderCachePageSize) ? atoi(HeaderCachePageSize) : 16384;
 595         h->db     = NULL;
 596         h->folder = safe_strdup (folder);
 597         h->crc    = generate_crc32();
 598
 599         if (! path || path[0] == '\0') {
 600                 FREE(& h->folder);
 601                 FREE(& h);
 602                 return NULL;
 603         }
 604
 605         path = mutt_hcache_per_folder(path, folder);
 606
 607         h->db = gdbm_open((char *) path, pagesize, GDBM_WRCREAT, 00600, NULL);
 608         if (h->db) {
 609                 return h;
 610         }
 611
 612         /* if rw failed try ro */
 613         h->db = gdbm_open((char *) path, pagesize, GDBM_READER, 00600, NULL);
 614         if(h->db) {
 615                 return h;
 616         } else {
 617                 FREE(& h->folder);
 618                 FREE(& h);
 619
 620                 return NULL;
 621         }
 622 }
 623
 624 void
 625 mutt_hcache_close(void *db)
 626 {
 627         struct header_cache *h = db;
 628
 629         if (! h) {
 630                 return;
 631         }
 632
 633         gdbm_close(h->db);
 634         FREE(& h->folder);
 635         FREE(& h);
 636 }
 637
 638 void *
 639 mutt_hcache_fetch(void *db, const char *filename, size_t (*keylen)(const char *fn))
 640 {
 641         struct header_cache *h = db;
 642         datum key;
 643         datum data;
 644         char path[_POSIX_PATH_MAX];
 645
 646         if (! h) {
 647                 return NULL;
 648         }
 649
 650         strncpy(path, h->folder, sizeof(path));
 651         strncat(path, filename, sizeof(path) - mutt_strlen(path));
 652
 653         key.dptr  = path;
 654         key.dsize = keylen(path);
 655
 656         data = gdbm_fetch(h->db, key);
 657
 658         if (! crc32_matches(data.dptr, h->crc)) {
 659                 free(data.dptr);
 660                 return NULL;
 661         }
 662
 663         return data.dptr;
 664 }
 665
 666 int
 667 mutt_hcache_store(void *db, const char *filename, HEADER *header, uint64_t uid_validity, size_t (*keylen)(const char *fn))
 668 {
 669         struct header_cache *h = db;
 670         datum key;
 671         datum data;
 672         char path[_POSIX_PATH_MAX];
 673         int ret;
 674
 675         if (! h) {
 676                 return -1;
 677         }
 678
 679         strncpy(path, h->folder, sizeof(path));
 680         strncat(path, filename, sizeof(path) - mutt_strlen(path));
 681
 682         key.dptr  = path;
 683         key.dsize = keylen(path);
 684
 685         data.dptr = mutt_hcache_dump(db, header, &data.dsize, uid_validity);
 686
 687         ret = gdbm_store(h->db, key, data, GDBM_REPLACE);
 688
 689         FREE(& data.dptr);
 690
 691         return ret;
 692 }
 693
 694 int
 695 mutt_hcache_delete(void *db, const char *filename, size_t (*keylen)(const char *fn))
 696 {
 697         datum key;
 698         struct header_cache *h = db;
 699         char path[_POSIX_PATH_MAX];
 700
 701         if (! h) {
 702                 return -1;
 703         }
 704
 705         strncpy(path, h->folder, sizeof(path));
 706         strncat(path, filename, sizeof(path) - mutt_strlen(path));
 707
 708         key.dptr  = path;
 709         key.dsize = keylen(path);
 710
 711         return gdbm_delete(h->db, key);
 712 }
 713 #elif HAVE_DB4
 714
 715 static void
 716 mutt_hcache_dbt_init(DBT *dbt, void *data, size_t len)
 717 {
 718         dbt->data = data;
 719         dbt->size = dbt->ulen = len;
 720         dbt->dlen = dbt->doff = 0;
 721         dbt->flags = DB_DBT_USERMEM;
 722 }
 723
 724 static void
 725 mutt_hcache_dbt_empty_init(DBT *dbt)
 726 {
 727         dbt->data = NULL;
 728         dbt->size = dbt->ulen = dbt->dlen = dbt->doff = 0;
 729         dbt->flags = 0;
 730 }
 731
 732 void *
 733 mutt_hcache_open(const char *path, const char *folder)
 734 {
 735         struct stat sb;
 736         u_int32_t createflags = DB_CREATE;
 737         int ret;
 738         struct header_cache *h = calloc(1, sizeof(HEADER_CACHE));
 739         int pagesize = atoi(HeaderCachePageSize);
 740
 741
 742         h->crc = generate_crc32();
 743
 744         if (! path || path[0] == '\0') {
 745                 FREE(& h);
 746                 return NULL;
 747         }
 748
 749         path = mutt_hcache_per_folder(path, folder);
 750
 751         snprintf (h->lockfile, _POSIX_PATH_MAX, "%s-lock-hack", path);
 752
 753         h->fd = open(h->lockfile, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
 754         if (h->fd < 0) {
 755                 FREE (&h);
 756                 return NULL;
 757         }
 758
 759         if (mx_lock_file(h->lockfile, h->fd, 1, 0, 5)) {
 760                 close(h->fd);
 761                 FREE (&h);
 762                 return NULL;
 763         }
 764
 765         ret = db_env_create(&h->env, 0);
 766         if (ret) {
 767                 mx_unlock_file(h->lockfile, h->fd, 0);
 768                 close(h->fd);
 769                 FREE(& h);
 770                 return NULL;
 771         }
 772
 773         ret = h->env->open(h->env, NULL, DB_INIT_MPOOL | DB_CREATE | DB_PRIVATE, 0600);
 774         if (! ret) {
 775                 ret = db_create(&h->db, h->env, 0);
 776                 if (ret) {
 777                         h->env->close(h->env, 0);
 778                         mx_unlock_file(h->lockfile, h->fd, 0);
 779                         close(h->fd);
 780                         FREE(& h);
 781                         return NULL;
 782                 }
 783         }
 784
 785         if (stat(path, &sb) != 0 && errno == ENOENT) {
 786                 createflags |= DB_EXCL;
 787                 h->db->set_pagesize(h->db, pagesize);
 788         }
 789
 790         ret = h->db->open(h->db, NULL, path, folder, DB_BTREE, createflags, 0600);
 791         if (ret) {
 792                 h->db->close(h->db, 0);
 793                 h->env->close(h->env, 0);
 794                 mx_unlock_file(h->lockfile, h->fd, 0);
 795                 close(h->fd);
 796                 FREE(& h);
 797                 return NULL;
 798         }
 799
 800         return h;
 801 }
 802
 803 void
 804 mutt_hcache_close(void *db)
 805 {
 806         struct header_cache *h = db;
 807         int ret;
 808
 809         if (! h) {
 810                 return;
 811         }
 812
 813         h->db->close(h->db, 0);
 814         h->env->close(h->env, 0);
 815         mx_unlock_file(h->lockfile, h->fd, 0);
 816         close(h->fd);
 817         FREE(& h);
 818 }
 819
 820 void *
 821 mutt_hcache_fetch(void *db, const char *filename, size_t (*keylen)(const char *fn))
 822 {
 823         DBT key;
 824         DBT data;
 825         struct header_cache *h = db;
 826
 827         if (! h) {
 828                 return NULL;
 829         }
 830
 831         filename++; /* skip '/' */
 832
 833         mutt_hcache_dbt_init(&key, (void *) filename, keylen(filename));
 834         mutt_hcache_dbt_empty_init(&data);
 835         data.flags = DB_DBT_MALLOC;
 836
 837         h->db->get(h->db, NULL, &key, &data, 0);
 838
 839         if (! crc32_matches(data.data, h->crc)) {
 840                 free(data.data);
 841                 return NULL;
 842         }
 843
 844         return data.data;
 845 }
 846
 847 int
 848 mutt_hcache_store(void *db, const char *filename, HEADER *header, uint64_t uid_validity, size_t (*keylen)(const char *fn))
 849 {
 850         DBT key;
 851         DBT data;
 852         int ret;
 853         struct header_cache *h = db;
 854
 855         if (! h) {
 856                 return -1;
 857         }
 858
 859         filename++; /* skip '/' */
 860
 861         mutt_hcache_dbt_init(&key, (void *) filename, keylen(filename));
 862
 863         mutt_hcache_dbt_empty_init(&data);
 864         data.flags = DB_DBT_USERMEM;
 865         data.data = mutt_hcache_dump(db, header, (signed int *) &data.size, uid_validity);
 866         data.ulen = data.size;
 867
 868         ret = h->db->put(h->db, NULL, &key, &data, 0);
 869
 870         FREE(& data.data);
 871
 872         return ret;
 873 }
 874
 875 int
 876 mutt_hcache_delete(void *db, const char *filename, size_t (*keylen)(const char *fn))
 877 {
 878         DBT key;
 879         struct header_cache *h = db;
 880
 881         if (! h) {
 882                 return -1;
 883         }
 884
 885         filename++; /* skip '/' */
 886
 887         mutt_hcache_dbt_init(&key, (void *) filename, keylen(filename));
 888         return h->db->del(h->db, NULL, &key, 0);
 889 }
 890 #endif
 891
 892 #endif /* USE_HCACHE */