git.ozlabs.org Git - ccan/blob - ccan/tdb2/open.c

   1 #include "private.h"
   2 #include <ccan/hash/hash.h>
   3 #include <assert.h>
   4
   5 /* all lock info, to detect double-opens (fcntl file don't nest!) */
   6 static struct tdb_file *files = NULL;
   7
   8 static struct tdb_file *find_file(dev_t device, ino_t ino)
   9 {
  10         struct tdb_file *i;
  11
  12         for (i = files; i; i = i->next) {
  13                 if (i->device == device && i->inode == ino) {
  14                         i->refcnt++;
  15                         break;
  16                 }
  17         }
  18         return i;
  19 }
  20
  21 static bool read_all(int fd, void *buf, size_t len)
  22 {
  23         while (len) {
  24                 ssize_t ret;
  25                 ret = read(fd, buf, len);
  26                 if (ret < 0)
  27                         return false;
  28                 if (ret == 0) {
  29                         /* ETOOSHORT? */
  30                         errno = EWOULDBLOCK;
  31                         return false;
  32                 }
  33                 buf = (char *)buf + ret;
  34                 len -= ret;
  35         }
  36         return true;
  37 }
  38
  39 static uint64_t random_number(struct tdb_context *tdb)
  40 {
  41         int fd;
  42         uint64_t ret = 0;
  43         struct timeval now;
  44
  45         fd = open("/dev/urandom", O_RDONLY);
  46         if (fd >= 0) {
  47                 if (read_all(fd, &ret, sizeof(ret))) {
  48                         close(fd);
  49                         return ret;
  50                 }
  51                 close(fd);
  52         }
  53         /* FIXME: Untested!  Based on Wikipedia protocol description! */
  54         fd = open("/dev/egd-pool", O_RDWR);
  55         if (fd >= 0) {
  56                 /* Command is 1, next byte is size we want to read. */
  57                 char cmd[2] = { 1, sizeof(uint64_t) };
  58                 if (write(fd, cmd, sizeof(cmd)) == sizeof(cmd)) {
  59                         char reply[1 + sizeof(uint64_t)];
  60                         int r = read(fd, reply, sizeof(reply));
  61                         if (r > 1) {
  62                                 /* Copy at least some bytes. */
  63                                 memcpy(&ret, reply+1, r - 1);
  64                                 if (reply[0] == sizeof(uint64_t)
  65                                     && r == sizeof(reply)) {
  66                                         close(fd);
  67                                         return ret;
  68                                 }
  69                         }
  70                 }
  71                 close(fd);
  72         }
  73
  74         /* Fallback: pid and time. */
  75         gettimeofday(&now, NULL);
  76         ret = getpid() * 100132289ULL + now.tv_sec * 1000000ULL + now.tv_usec;
  77         tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
  78                    "tdb_open: random from getpid and time");
  79         return ret;
  80 }
  81
  82 struct new_database {
  83         struct tdb_header hdr;
  84         struct tdb_freetable ftable;
  85 };
  86
  87 /* initialise a new database */
  88 static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb,
  89                                        struct tdb_attribute_seed *seed,
  90                                        struct tdb_header *hdr)
  91 {
  92         /* We make it up in memory, then write it out if not internal */
  93         struct new_database newdb;
  94         unsigned int magic_len;
  95         ssize_t rlen;
  96         enum TDB_ERROR ecode;
  97
  98         /* Fill in the header */
  99         newdb.hdr.version = TDB_VERSION;
 100         if (seed)
 101                 newdb.hdr.hash_seed = seed->seed;
 102         else
 103                 newdb.hdr.hash_seed = random_number(tdb);
 104         newdb.hdr.hash_test = TDB_HASH_MAGIC;
 105         newdb.hdr.hash_test = tdb->hash_fn(&newdb.hdr.hash_test,
 106                                            sizeof(newdb.hdr.hash_test),
 107                                            newdb.hdr.hash_seed,
 108                                            tdb->hash_data);
 109         newdb.hdr.recovery = 0;
 110         newdb.hdr.features_used = newdb.hdr.features_offered = TDB_FEATURE_MASK;
 111         newdb.hdr.seqnum = 0;
 112         memset(newdb.hdr.reserved, 0, sizeof(newdb.hdr.reserved));
 113         /* Initial hashes are empty. */
 114         memset(newdb.hdr.hashtable, 0, sizeof(newdb.hdr.hashtable));
 115
 116         /* Free is empty. */
 117         newdb.hdr.free_table = offsetof(struct new_database, ftable);
 118         memset(&newdb.ftable, 0, sizeof(newdb.ftable));
 119         ecode = set_header(NULL, &newdb.ftable.hdr, TDB_FTABLE_MAGIC, 0,
 120                            sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
 121                            sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
 122                            0);
 123         if (ecode != TDB_SUCCESS) {
 124                 return ecode;
 125         }
 126
 127         /* Magic food */
 128         memset(newdb.hdr.magic_food, 0, sizeof(newdb.hdr.magic_food));
 129         strcpy(newdb.hdr.magic_food, TDB_MAGIC_FOOD);
 130
 131         /* This creates an endian-converted database, as if read from disk */
 132         magic_len = sizeof(newdb.hdr.magic_food);
 133         tdb_convert(tdb,
 134                     (char *)&newdb.hdr + magic_len, sizeof(newdb) - magic_len);
 135
 136         *hdr = newdb.hdr;
 137
 138         if (tdb->flags & TDB_INTERNAL) {
 139                 tdb->file->map_size = sizeof(newdb);
 140                 tdb->file->map_ptr = malloc(tdb->file->map_size);
 141                 if (!tdb->file->map_ptr) {
 142                         return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
 143                                           "tdb_new_database:"
 144                                           " failed to allocate");
 145                 }
 146                 memcpy(tdb->file->map_ptr, &newdb, tdb->file->map_size);
 147                 return TDB_SUCCESS;
 148         }
 149         if (lseek(tdb->file->fd, 0, SEEK_SET) == -1) {
 150                 return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 151                                   "tdb_new_database:"
 152                                   " failed to seek: %s", strerror(errno));
 153         }
 154
 155         if (ftruncate(tdb->file->fd, 0) == -1) {
 156                 return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 157                                   "tdb_new_database:"
 158                                   " failed to truncate: %s", strerror(errno));
 159         }
 160
 161         rlen = write(tdb->file->fd, &newdb, sizeof(newdb));
 162         if (rlen != sizeof(newdb)) {
 163                 if (rlen >= 0)
 164                         errno = ENOSPC;
 165                 return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 166                                   "tdb_new_database: %zi writing header: %s",
 167                                   rlen, strerror(errno));
 168         }
 169         return TDB_SUCCESS;
 170 }
 171
 172 static enum TDB_ERROR tdb_new_file(struct tdb_context *tdb)
 173 {
 174         tdb->file = malloc(sizeof(*tdb->file));
 175         if (!tdb->file)
 176                 return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
 177                                   "tdb_open: cannot alloc tdb_file structure");
 178         tdb->file->num_lockrecs = 0;
 179         tdb->file->lockrecs = NULL;
 180         tdb->file->allrecord_lock.count = 0;
 181         tdb->file->refcnt = 1;
 182         return TDB_SUCCESS;
 183 }
 184
 185 enum TDB_ERROR tdb_set_attribute(struct tdb_context *tdb,
 186                                  const union tdb_attribute *attr)
 187 {
 188         switch (attr->base.attr) {
 189         case TDB_ATTRIBUTE_LOG:
 190                 tdb->log_fn = attr->log.fn;
 191                 tdb->log_data = attr->log.data;
 192                 break;
 193         case TDB_ATTRIBUTE_HASH:
 194         case TDB_ATTRIBUTE_SEED:
 195         case TDB_ATTRIBUTE_OPENHOOK:
 196                 return tdb->last_error
 197                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 198                                      TDB_LOG_USE_ERROR,
 199                                      "tdb_set_attribute:"
 200                                      " cannot set %s after opening",
 201                                      attr->base.attr == TDB_ATTRIBUTE_HASH
 202                                      ? "TDB_ATTRIBUTE_HASH"
 203                                      : attr->base.attr == TDB_ATTRIBUTE_SEED
 204                                      ? "TDB_ATTRIBUTE_SEED"
 205                                      : "TDB_ATTRIBUTE_OPENHOOK");
 206         case TDB_ATTRIBUTE_STATS:
 207                 return tdb->last_error
 208                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 209                                      TDB_LOG_USE_ERROR,
 210                                      "tdb_set_attribute:"
 211                                      " cannot set TDB_ATTRIBUTE_STATS");
 212         case TDB_ATTRIBUTE_FLOCK:
 213                 tdb->lock_fn = attr->flock.lock;
 214                 tdb->unlock_fn = attr->flock.unlock;
 215                 tdb->lock_data = attr->flock.data;
 216                 break;
 217         default:
 218                 return tdb->last_error
 219                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 220                                      TDB_LOG_USE_ERROR,
 221                                      "tdb_set_attribute:"
 222                                      " unknown attribute type %u",
 223                                      attr->base.attr);
 224         }
 225         return TDB_SUCCESS;
 226 }
 227
 228 static uint64_t jenkins_hash(const void *key, size_t length, uint64_t seed,
 229                              void *unused)
 230 {
 231         uint64_t ret;
 232         /* hash64_stable assumes lower bits are more important; they are a
 233          * slightly better hash.  We use the upper bits first, so swap them. */
 234         ret = hash64_stable((const unsigned char *)key, length, seed);
 235         return (ret >> 32) | (ret << 32);
 236 }
 237
 238 enum TDB_ERROR tdb_get_attribute(struct tdb_context *tdb,
 239                                  union tdb_attribute *attr)
 240 {
 241         switch (attr->base.attr) {
 242         case TDB_ATTRIBUTE_LOG:
 243                 if (!tdb->log_fn)
 244                         return tdb->last_error = TDB_ERR_NOEXIST;
 245                 attr->log.fn = tdb->log_fn;
 246                 attr->log.data = tdb->log_data;
 247                 break;
 248         case TDB_ATTRIBUTE_HASH:
 249                 attr->hash.fn = tdb->hash_fn;
 250                 attr->hash.data = tdb->hash_data;
 251                 break;
 252         case TDB_ATTRIBUTE_SEED:
 253                 attr->seed.seed = tdb->hash_seed;
 254                 break;
 255         case TDB_ATTRIBUTE_OPENHOOK:
 256                 return tdb->last_error
 257                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 258                                      TDB_LOG_USE_ERROR,
 259                                      "tdb_get_attribute:"
 260                                      " cannot get TDB_ATTRIBUTE_OPENHOOK");
 261         case TDB_ATTRIBUTE_STATS: {
 262                 size_t size = attr->stats.size;
 263                 if (size > tdb->stats.size)
 264                         size = tdb->stats.size;
 265                 memcpy(&attr->stats, &tdb->stats, size);
 266                 break;
 267         }
 268         case TDB_ATTRIBUTE_FLOCK:
 269                 attr->flock.lock = tdb->lock_fn;
 270                 attr->flock.unlock = tdb->unlock_fn;
 271                 attr->flock.data = tdb->lock_data;
 272                 break;
 273         default:
 274                 return tdb->last_error
 275                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 276                                      TDB_LOG_USE_ERROR,
 277                                      "tdb_get_attribute:"
 278                                      " unknown attribute type %u",
 279                                      attr->base.attr);
 280         }
 281         attr->base.next = NULL;
 282         return TDB_SUCCESS;
 283 }
 284
 285 void tdb_unset_attribute(struct tdb_context *tdb,
 286                          enum tdb_attribute_type type)
 287 {
 288         switch (type) {
 289         case TDB_ATTRIBUTE_LOG:
 290                 tdb->log_fn = NULL;
 291                 break;
 292         case TDB_ATTRIBUTE_HASH:
 293         case TDB_ATTRIBUTE_SEED:
 294         case TDB_ATTRIBUTE_OPENHOOK:
 295                 tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 296                            "tdb_unset_attribute: cannot unset %s after opening",
 297                            type == TDB_ATTRIBUTE_HASH
 298                            ? "TDB_ATTRIBUTE_HASH"
 299                            : type == TDB_ATTRIBUTE_SEED
 300                            ? "TDB_ATTRIBUTE_SEED"
 301                            : "TDB_ATTRIBUTE_OPENHOOK");
 302                 break;
 303         case TDB_ATTRIBUTE_STATS:
 304                 tdb_logerr(tdb, TDB_ERR_EINVAL,
 305                            TDB_LOG_USE_ERROR,
 306                            "tdb_unset_attribute:"
 307                            "cannot unset TDB_ATTRIBUTE_STATS");
 308                 break;
 309         case TDB_ATTRIBUTE_FLOCK:
 310                 tdb->lock_fn = tdb_fcntl_lock;
 311                 tdb->unlock_fn = tdb_fcntl_unlock;
 312                 break;
 313         default:
 314                 tdb_logerr(tdb, TDB_ERR_EINVAL,
 315                            TDB_LOG_USE_ERROR,
 316                            "tdb_unset_attribute: unknown attribute type %u",
 317                            type);
 318         }
 319 }
 320
 321 struct tdb_context *tdb_open(const char *name, int tdb_flags,
 322                              int open_flags, mode_t mode,
 323                              union tdb_attribute *attr)
 324 {
 325         struct tdb_context *tdb;
 326         struct stat st;
 327         int saved_errno = 0;
 328         uint64_t hash_test;
 329         unsigned v;
 330         ssize_t rlen;
 331         struct tdb_header hdr;
 332         struct tdb_attribute_seed *seed = NULL;
 333         struct tdb_attribute_openhook *openhook = NULL;
 334         tdb_bool_err berr;
 335         enum TDB_ERROR ecode;
 336         int openlock;
 337
 338         tdb = malloc(sizeof(*tdb) + (name ? strlen(name) + 1 : 0));
 339         if (!tdb) {
 340                 /* Can't log this */
 341                 errno = ENOMEM;
 342                 return NULL;
 343         }
 344         /* Set name immediately for logging functions. */
 345         if (name) {
 346                 tdb->name = strcpy((char *)(tdb + 1), name);
 347         } else {
 348                 tdb->name = NULL;
 349         }
 350         tdb->direct_access = 0;
 351         tdb->flags = tdb_flags;
 352         tdb->log_fn = NULL;
 353         tdb->transaction = NULL;
 354         tdb->access = NULL;
 355         tdb->last_error = TDB_SUCCESS;
 356         tdb->file = NULL;
 357         tdb->lock_fn = tdb_fcntl_lock;
 358         tdb->unlock_fn = tdb_fcntl_unlock;
 359         tdb->hash_fn = jenkins_hash;
 360         memset(&tdb->stats, 0, sizeof(tdb->stats));
 361         tdb->stats.base.attr = TDB_ATTRIBUTE_STATS;
 362         tdb->stats.size = sizeof(tdb->stats);
 363         tdb_io_init(tdb);
 364
 365         while (attr) {
 366                 switch (attr->base.attr) {
 367                 case TDB_ATTRIBUTE_HASH:
 368                         tdb->hash_fn = attr->hash.fn;
 369                         tdb->hash_data = attr->hash.data;
 370                         break;
 371                 case TDB_ATTRIBUTE_SEED:
 372                         seed = &attr->seed;
 373                         break;
 374                 case TDB_ATTRIBUTE_OPENHOOK:
 375                         openhook = &attr->openhook;
 376                         break;
 377                 default:
 378                         /* These are set as normal. */
 379                         ecode = tdb_set_attribute(tdb, attr);
 380                         if (ecode != TDB_SUCCESS)
 381                                 goto fail;
 382                 }
 383                 attr = attr->base.next;
 384         }
 385
 386         if (tdb_flags & ~(TDB_INTERNAL | TDB_NOLOCK | TDB_NOMMAP | TDB_CONVERT
 387                           | TDB_NOSYNC | TDB_SEQNUM | TDB_ALLOW_NESTING)) {
 388                 ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 389                                    "tdb_open: unknown flags %u", tdb_flags);
 390                 goto fail;
 391         }
 392
 393         if ((open_flags & O_ACCMODE) == O_WRONLY) {
 394                 ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 395                                    "tdb_open: can't open tdb %s write-only",
 396                                    name);
 397                 goto fail;
 398         }
 399
 400         if ((open_flags & O_ACCMODE) == O_RDONLY) {
 401                 tdb->read_only = true;
 402                 tdb->mmap_flags = PROT_READ;
 403                 openlock = F_RDLCK;
 404         } else {
 405                 tdb->read_only = false;
 406                 tdb->mmap_flags = PROT_READ | PROT_WRITE;
 407                 openlock = F_WRLCK;
 408         }
 409
 410         /* internal databases don't need any of the rest. */
 411         if (tdb->flags & TDB_INTERNAL) {
 412                 tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP);
 413                 ecode = tdb_new_file(tdb);
 414                 if (ecode != TDB_SUCCESS) {
 415                         goto fail;
 416                 }
 417                 tdb->file->fd = -1;
 418                 ecode = tdb_new_database(tdb, seed, &hdr);
 419                 if (ecode != TDB_SUCCESS) {
 420                         goto fail;
 421                 }
 422                 tdb_convert(tdb, &hdr.hash_seed, sizeof(hdr.hash_seed));
 423                 tdb->hash_seed = hdr.hash_seed;
 424                 tdb_ftable_init(tdb);
 425                 return tdb;
 426         }
 427
 428         if (stat(name, &st) != -1)
 429                 tdb->file = find_file(st.st_dev, st.st_ino);
 430
 431         if (!tdb->file) {
 432                 int fd;
 433
 434                 if ((fd = open(name, open_flags, mode)) == -1) {
 435                         /* errno set by open(2) */
 436                         saved_errno = errno;
 437                         tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 438                                    "tdb_open: could not open file %s: %s",
 439                                    name, strerror(errno));
 440                         goto fail_errno;
 441                 }
 442
 443                 /* on exec, don't inherit the fd */
 444                 v = fcntl(fd, F_GETFD, 0);
 445                 fcntl(fd, F_SETFD, v | FD_CLOEXEC);
 446
 447                 if (fstat(fd, &st) == -1) {
 448                         saved_errno = errno;
 449                         tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 450                                    "tdb_open: could not stat open %s: %s",
 451                                    name, strerror(errno));
 452                         close(fd);
 453                         goto fail_errno;
 454                 }
 455
 456                 ecode = tdb_new_file(tdb);
 457                 if (ecode != TDB_SUCCESS) {
 458                         close(fd);
 459                         goto fail;
 460                 }
 461
 462                 tdb->file->next = files;
 463                 tdb->file->fd = fd;
 464                 tdb->file->device = st.st_dev;
 465                 tdb->file->inode = st.st_ino;
 466                 tdb->file->map_ptr = NULL;
 467                 tdb->file->map_size = sizeof(struct tdb_header);
 468         }
 469
 470         /* ensure there is only one process initialising at once */
 471         ecode = tdb_lock_open(tdb, openlock, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
 472         if (ecode != TDB_SUCCESS) {
 473                 saved_errno = errno;
 474                 goto fail_errno;
 475         }
 476
 477         /* call their open hook if they gave us one. */
 478         if (openhook) {
 479                 ecode = openhook->fn(tdb->file->fd, openhook->data);
 480                 if (ecode != TDB_SUCCESS) {
 481                         tdb_logerr(tdb, ecode, TDB_LOG_ERROR,
 482                                    "tdb_open: open hook failed");
 483                         goto fail;
 484                 }
 485                 open_flags |= O_CREAT;
 486         }
 487
 488         /* If they used O_TRUNC, read will return 0. */
 489         rlen = pread(tdb->file->fd, &hdr, sizeof(hdr), 0);
 490         if (rlen == 0 && (open_flags & O_CREAT)) {
 491                 ecode = tdb_new_database(tdb, seed, &hdr);
 492                 if (ecode != TDB_SUCCESS) {
 493                         goto fail;
 494                 }
 495         } else if (rlen < 0) {
 496                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 497                                    "tdb_open: error %s reading %s",
 498                                    strerror(errno), name);
 499                 goto fail;
 500         } else if (rlen < sizeof(hdr)
 501                    || strcmp(hdr.magic_food, TDB_MAGIC_FOOD) != 0) {
 502                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 503                                    "tdb_open: %s is not a tdb file", name);
 504                 goto fail;
 505         }
 506
 507         if (hdr.version != TDB_VERSION) {
 508                 if (hdr.version == bswap_64(TDB_VERSION))
 509                         tdb->flags |= TDB_CONVERT;
 510                 else {
 511                         /* wrong version */
 512                         ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 513                                            "tdb_open:"
 514                                            " %s is unknown version 0x%llx",
 515                                            name, (long long)hdr.version);
 516                         goto fail;
 517                 }
 518         }
 519
 520         tdb_convert(tdb, &hdr, sizeof(hdr));
 521         tdb->hash_seed = hdr.hash_seed;
 522         hash_test = TDB_HASH_MAGIC;
 523         hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
 524         if (hdr.hash_test != hash_test) {
 525                 /* wrong hash variant */
 526                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 527                                    "tdb_open:"
 528                                    " %s uses a different hash function",
 529                                    name);
 530                 goto fail;
 531         }
 532
 533         /* Clear any features we don't understand. */
 534         if ((open_flags & O_ACCMODE) != O_RDONLY) {
 535                 hdr.features_used &= TDB_FEATURE_MASK;
 536                 if (tdb_write_convert(tdb, offsetof(struct tdb_header,
 537                                                     features_used),
 538                                       &hdr.features_used,
 539                                       sizeof(hdr.features_used)) == -1)
 540                         goto fail;
 541         }
 542
 543         tdb_unlock_open(tdb, openlock);
 544
 545         /* This make sure we have current map_size and mmap. */
 546         tdb->methods->oob(tdb, tdb->file->map_size + 1, true);
 547
 548         /* Now it's fully formed, recover if necessary. */
 549         berr = tdb_needs_recovery(tdb);
 550         if (unlikely(berr != false)) {
 551                 if (berr < 0) {
 552                         ecode = berr;
 553                         goto fail;
 554                 }
 555                 ecode = tdb_lock_and_recover(tdb);
 556                 if (ecode != TDB_SUCCESS) {
 557                         goto fail;
 558                 }
 559         }
 560
 561         ecode = tdb_ftable_init(tdb);
 562         if (ecode != TDB_SUCCESS) {
 563                 goto fail;
 564         }
 565
 566         /* Add to linked list if we're new. */
 567         if (tdb->file->refcnt == 1)
 568                 files = tdb->file;
 569         return tdb;
 570
 571  fail:
 572         /* Map ecode to some logical errno. */
 573         switch (ecode) {
 574         case TDB_ERR_CORRUPT:
 575         case TDB_ERR_IO:
 576                 saved_errno = EIO;
 577                 break;
 578         case TDB_ERR_LOCK:
 579                 saved_errno = EWOULDBLOCK;
 580                 break;
 581         case TDB_ERR_OOM:
 582                 saved_errno = ENOMEM;
 583                 break;
 584         case TDB_ERR_EINVAL:
 585                 saved_errno = EINVAL;
 586                 break;
 587         default:
 588                 saved_errno = EINVAL;
 589                 break;
 590         }
 591
 592 fail_errno:
 593 #ifdef TDB_TRACE
 594         close(tdb->tracefd);
 595 #endif
 596         if (tdb->file) {
 597                 tdb_lock_cleanup(tdb);
 598                 if (--tdb->file->refcnt == 0) {
 599                         assert(tdb->file->num_lockrecs == 0);
 600                         if (tdb->file->map_ptr) {
 601                                 if (tdb->flags & TDB_INTERNAL) {
 602                                         free(tdb->file->map_ptr);
 603                                 } else
 604                                         tdb_munmap(tdb->file);
 605                         }
 606                         if (close(tdb->file->fd) != 0)
 607                                 tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 608                                            "tdb_open: failed to close tdb fd"
 609                                            " on error: %s", strerror(errno));
 610                         free(tdb->file->lockrecs);
 611                         free(tdb->file);
 612                 }
 613         }
 614
 615         free(tdb);
 616         errno = saved_errno;
 617         return NULL;
 618 }
 619
 620 int tdb_close(struct tdb_context *tdb)
 621 {
 622         int ret = 0;
 623
 624         tdb_trace(tdb, "tdb_close");
 625
 626         if (tdb->transaction) {
 627                 tdb_transaction_cancel(tdb);
 628         }
 629
 630         if (tdb->file->map_ptr) {
 631                 if (tdb->flags & TDB_INTERNAL)
 632                         free(tdb->file->map_ptr);
 633                 else
 634                         tdb_munmap(tdb->file);
 635         }
 636         if (tdb->file) {
 637                 struct tdb_file **i;
 638
 639                 tdb_lock_cleanup(tdb);
 640                 if (--tdb->file->refcnt == 0) {
 641                         ret = close(tdb->file->fd);
 642
 643                         /* Remove from files list */
 644                         for (i = &files; *i; i = &(*i)->next) {
 645                                 if (*i == tdb->file) {
 646                                         *i = tdb->file->next;
 647                                         break;
 648                                 }
 649                         }
 650                         free(tdb->file->lockrecs);
 651                         free(tdb->file);
 652                 }
 653         }
 654
 655 #ifdef TDB_TRACE
 656         close(tdb->tracefd);
 657 #endif
 658         free(tdb);
 659
 660         return ret;
 661 }