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   1  /*
   2    Trivial Database 2: opening and closing TDBs
   3    Copyright (C) Rusty Russell 2010
   4
   5    This library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 3 of the License, or (at your option) any later version.
   9
  10    This library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  17 */
  18 #include "private.h"
  19 #include <assert.h>
  20
  21 /* all tdbs, to detect double-opens (fcntl file don't nest!) */
  22 static struct tdb_context *tdbs = NULL;
  23
  24 static struct tdb_file *find_file(dev_t device, ino_t ino)
  25 {
  26         struct tdb_context *i;
  27
  28         for (i = tdbs; i; i = i->next) {
  29                 if (i->file->device == device && i->file->inode == ino) {
  30                         i->file->refcnt++;
  31                         return i->file;
  32                 }
  33         }
  34         return NULL;
  35 }
  36
  37 static bool read_all(int fd, void *buf, size_t len)
  38 {
  39         while (len) {
  40                 ssize_t ret;
  41                 ret = read(fd, buf, len);
  42                 if (ret < 0)
  43                         return false;
  44                 if (ret == 0) {
  45                         /* ETOOSHORT? */
  46                         errno = EWOULDBLOCK;
  47                         return false;
  48                 }
  49                 buf = (char *)buf + ret;
  50                 len -= ret;
  51         }
  52         return true;
  53 }
  54
  55 static uint64_t random_number(struct tdb_context *tdb)
  56 {
  57         int fd;
  58         uint64_t ret = 0;
  59         struct timeval now;
  60
  61         fd = open("/dev/urandom", O_RDONLY);
  62         if (fd >= 0) {
  63                 if (read_all(fd, &ret, sizeof(ret))) {
  64                         close(fd);
  65                         return ret;
  66                 }
  67                 close(fd);
  68         }
  69         /* FIXME: Untested!  Based on Wikipedia protocol description! */
  70         fd = open("/dev/egd-pool", O_RDWR);
  71         if (fd >= 0) {
  72                 /* Command is 1, next byte is size we want to read. */
  73                 char cmd[2] = { 1, sizeof(uint64_t) };
  74                 if (write(fd, cmd, sizeof(cmd)) == sizeof(cmd)) {
  75                         char reply[1 + sizeof(uint64_t)];
  76                         int r = read(fd, reply, sizeof(reply));
  77                         if (r > 1) {
  78                                 /* Copy at least some bytes. */
  79                                 memcpy(&ret, reply+1, r - 1);
  80                                 if (reply[0] == sizeof(uint64_t)
  81                                     && r == sizeof(reply)) {
  82                                         close(fd);
  83                                         return ret;
  84                                 }
  85                         }
  86                 }
  87                 close(fd);
  88         }
  89
  90         /* Fallback: pid and time. */
  91         gettimeofday(&now, NULL);
  92         ret = getpid() * 100132289ULL + now.tv_sec * 1000000ULL + now.tv_usec;
  93         tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
  94                    "tdb_open: random from getpid and time");
  95         return ret;
  96 }
  97
  98 struct new_database {
  99         struct tdb_header hdr;
 100         struct tdb_freetable ftable;
 101 };
 102
 103 /* initialise a new database */
 104 static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb,
 105                                        struct tdb_attribute_seed *seed,
 106                                        struct tdb_header *hdr)
 107 {
 108         /* We make it up in memory, then write it out if not internal */
 109         struct new_database newdb;
 110         unsigned int magic_len;
 111         ssize_t rlen;
 112         enum TDB_ERROR ecode;
 113
 114         /* Fill in the header */
 115         newdb.hdr.version = TDB_VERSION;
 116         if (seed)
 117                 newdb.hdr.hash_seed = seed->seed;
 118         else
 119                 newdb.hdr.hash_seed = random_number(tdb);
 120         newdb.hdr.hash_test = TDB_HASH_MAGIC;
 121         newdb.hdr.hash_test = tdb->hash_fn(&newdb.hdr.hash_test,
 122                                            sizeof(newdb.hdr.hash_test),
 123                                            newdb.hdr.hash_seed,
 124                                            tdb->hash_data);
 125         newdb.hdr.recovery = 0;
 126         newdb.hdr.features_used = newdb.hdr.features_offered = TDB_FEATURE_MASK;
 127         newdb.hdr.seqnum = 0;
 128         memset(newdb.hdr.reserved, 0, sizeof(newdb.hdr.reserved));
 129         /* Initial hashes are empty. */
 130         memset(newdb.hdr.hashtable, 0, sizeof(newdb.hdr.hashtable));
 131
 132         /* Free is empty. */
 133         newdb.hdr.free_table = offsetof(struct new_database, ftable);
 134         memset(&newdb.ftable, 0, sizeof(newdb.ftable));
 135         ecode = set_header(NULL, &newdb.ftable.hdr, TDB_FTABLE_MAGIC, 0,
 136                            sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
 137                            sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
 138                            0);
 139         if (ecode != TDB_SUCCESS) {
 140                 return ecode;
 141         }
 142
 143         /* Magic food */
 144         memset(newdb.hdr.magic_food, 0, sizeof(newdb.hdr.magic_food));
 145         strcpy(newdb.hdr.magic_food, TDB_MAGIC_FOOD);
 146
 147         /* This creates an endian-converted database, as if read from disk */
 148         magic_len = sizeof(newdb.hdr.magic_food);
 149         tdb_convert(tdb,
 150                     (char *)&newdb.hdr + magic_len, sizeof(newdb) - magic_len);
 151
 152         *hdr = newdb.hdr;
 153
 154         if (tdb->flags & TDB_INTERNAL) {
 155                 tdb->file->map_size = sizeof(newdb);
 156                 tdb->file->map_ptr = malloc(tdb->file->map_size);
 157                 if (!tdb->file->map_ptr) {
 158                         return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
 159                                           "tdb_new_database:"
 160                                           " failed to allocate");
 161                 }
 162                 memcpy(tdb->file->map_ptr, &newdb, tdb->file->map_size);
 163                 return TDB_SUCCESS;
 164         }
 165         if (lseek(tdb->file->fd, 0, SEEK_SET) == -1) {
 166                 return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 167                                   "tdb_new_database:"
 168                                   " failed to seek: %s", strerror(errno));
 169         }
 170
 171         if (ftruncate(tdb->file->fd, 0) == -1) {
 172                 return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 173                                   "tdb_new_database:"
 174                                   " failed to truncate: %s", strerror(errno));
 175         }
 176
 177         rlen = write(tdb->file->fd, &newdb, sizeof(newdb));
 178         if (rlen != sizeof(newdb)) {
 179                 if (rlen >= 0)
 180                         errno = ENOSPC;
 181                 return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 182                                   "tdb_new_database: %zi writing header: %s",
 183                                   rlen, strerror(errno));
 184         }
 185         return TDB_SUCCESS;
 186 }
 187
 188 static enum TDB_ERROR tdb_new_file(struct tdb_context *tdb)
 189 {
 190         tdb->file = malloc(sizeof(*tdb->file));
 191         if (!tdb->file)
 192                 return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
 193                                   "tdb_open: cannot alloc tdb_file structure");
 194         tdb->file->num_lockrecs = 0;
 195         tdb->file->lockrecs = NULL;
 196         tdb->file->allrecord_lock.count = 0;
 197         tdb->file->refcnt = 1;
 198         return TDB_SUCCESS;
 199 }
 200
 201 enum TDB_ERROR tdb_set_attribute(struct tdb_context *tdb,
 202                                  const union tdb_attribute *attr)
 203 {
 204         switch (attr->base.attr) {
 205         case TDB_ATTRIBUTE_LOG:
 206                 tdb->log_fn = attr->log.fn;
 207                 tdb->log_data = attr->log.data;
 208                 break;
 209         case TDB_ATTRIBUTE_HASH:
 210         case TDB_ATTRIBUTE_SEED:
 211         case TDB_ATTRIBUTE_OPENHOOK:
 212                 return tdb->last_error
 213                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 214                                      TDB_LOG_USE_ERROR,
 215                                      "tdb_set_attribute:"
 216                                      " cannot set %s after opening",
 217                                      attr->base.attr == TDB_ATTRIBUTE_HASH
 218                                      ? "TDB_ATTRIBUTE_HASH"
 219                                      : attr->base.attr == TDB_ATTRIBUTE_SEED
 220                                      ? "TDB_ATTRIBUTE_SEED"
 221                                      : "TDB_ATTRIBUTE_OPENHOOK");
 222         case TDB_ATTRIBUTE_STATS:
 223                 return tdb->last_error
 224                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 225                                      TDB_LOG_USE_ERROR,
 226                                      "tdb_set_attribute:"
 227                                      " cannot set TDB_ATTRIBUTE_STATS");
 228         case TDB_ATTRIBUTE_FLOCK:
 229                 tdb->lock_fn = attr->flock.lock;
 230                 tdb->unlock_fn = attr->flock.unlock;
 231                 tdb->lock_data = attr->flock.data;
 232                 break;
 233         default:
 234                 return tdb->last_error
 235                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 236                                      TDB_LOG_USE_ERROR,
 237                                      "tdb_set_attribute:"
 238                                      " unknown attribute type %u",
 239                                      attr->base.attr);
 240         }
 241         return TDB_SUCCESS;
 242 }
 243
 244 enum TDB_ERROR tdb_get_attribute(struct tdb_context *tdb,
 245                                  union tdb_attribute *attr)
 246 {
 247         switch (attr->base.attr) {
 248         case TDB_ATTRIBUTE_LOG:
 249                 if (!tdb->log_fn)
 250                         return tdb->last_error = TDB_ERR_NOEXIST;
 251                 attr->log.fn = tdb->log_fn;
 252                 attr->log.data = tdb->log_data;
 253                 break;
 254         case TDB_ATTRIBUTE_HASH:
 255                 attr->hash.fn = tdb->hash_fn;
 256                 attr->hash.data = tdb->hash_data;
 257                 break;
 258         case TDB_ATTRIBUTE_SEED:
 259                 attr->seed.seed = tdb->hash_seed;
 260                 break;
 261         case TDB_ATTRIBUTE_OPENHOOK:
 262                 if (!tdb->openhook)
 263                         return tdb->last_error = TDB_ERR_NOEXIST;
 264                 attr->openhook.fn = tdb->openhook;
 265                 attr->openhook.data = tdb->openhook_data;
 266                 break;
 267         case TDB_ATTRIBUTE_STATS: {
 268                 size_t size = attr->stats.size;
 269                 if (size > tdb->stats.size)
 270                         size = tdb->stats.size;
 271                 memcpy(&attr->stats, &tdb->stats, size);
 272                 break;
 273         }
 274         case TDB_ATTRIBUTE_FLOCK:
 275                 attr->flock.lock = tdb->lock_fn;
 276                 attr->flock.unlock = tdb->unlock_fn;
 277                 attr->flock.data = tdb->lock_data;
 278                 break;
 279         default:
 280                 return tdb->last_error
 281                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 282                                      TDB_LOG_USE_ERROR,
 283                                      "tdb_get_attribute:"
 284                                      " unknown attribute type %u",
 285                                      attr->base.attr);
 286         }
 287         attr->base.next = NULL;
 288         return TDB_SUCCESS;
 289 }
 290
 291 void tdb_unset_attribute(struct tdb_context *tdb,
 292                          enum tdb_attribute_type type)
 293 {
 294         switch (type) {
 295         case TDB_ATTRIBUTE_LOG:
 296                 tdb->log_fn = NULL;
 297                 break;
 298         case TDB_ATTRIBUTE_OPENHOOK:
 299                 tdb->openhook = NULL;
 300                 break;
 301         case TDB_ATTRIBUTE_HASH:
 302         case TDB_ATTRIBUTE_SEED:
 303                 tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 304                            "tdb_unset_attribute: cannot unset %s after opening",
 305                            type == TDB_ATTRIBUTE_HASH
 306                            ? "TDB_ATTRIBUTE_HASH"
 307                            : "TDB_ATTRIBUTE_SEED");
 308                 break;
 309         case TDB_ATTRIBUTE_STATS:
 310                 tdb_logerr(tdb, TDB_ERR_EINVAL,
 311                            TDB_LOG_USE_ERROR,
 312                            "tdb_unset_attribute:"
 313                            "cannot unset TDB_ATTRIBUTE_STATS");
 314                 break;
 315         case TDB_ATTRIBUTE_FLOCK:
 316                 tdb->lock_fn = tdb_fcntl_lock;
 317                 tdb->unlock_fn = tdb_fcntl_unlock;
 318                 break;
 319         default:
 320                 tdb_logerr(tdb, TDB_ERR_EINVAL,
 321                            TDB_LOG_USE_ERROR,
 322                            "tdb_unset_attribute: unknown attribute type %u",
 323                            type);
 324         }
 325 }
 326
 327 struct tdb_context *tdb_open(const char *name, int tdb_flags,
 328                              int open_flags, mode_t mode,
 329                              union tdb_attribute *attr)
 330 {
 331         struct tdb_context *tdb;
 332         struct stat st;
 333         int saved_errno = 0;
 334         uint64_t hash_test;
 335         unsigned v;
 336         ssize_t rlen;
 337         struct tdb_header hdr;
 338         struct tdb_attribute_seed *seed = NULL;
 339         tdb_bool_err berr;
 340         enum TDB_ERROR ecode;
 341         int openlock;
 342
 343         tdb = malloc(sizeof(*tdb) + (name ? strlen(name) + 1 : 0));
 344         if (!tdb) {
 345                 /* Can't log this */
 346                 errno = ENOMEM;
 347                 return NULL;
 348         }
 349         /* Set name immediately for logging functions. */
 350         if (name) {
 351                 tdb->name = strcpy((char *)(tdb + 1), name);
 352         } else {
 353                 tdb->name = NULL;
 354         }
 355         tdb->flags = tdb_flags;
 356         tdb->log_fn = NULL;
 357         tdb->open_flags = open_flags;
 358         tdb->last_error = TDB_SUCCESS;
 359         tdb->file = NULL;
 360         tdb->openhook = NULL;
 361         tdb->lock_fn = tdb_fcntl_lock;
 362         tdb->unlock_fn = tdb_fcntl_unlock;
 363         tdb->hash_fn = tdb_jenkins_hash;
 364         memset(&tdb->stats, 0, sizeof(tdb->stats));
 365         tdb->stats.base.attr = TDB_ATTRIBUTE_STATS;
 366         tdb->stats.size = sizeof(tdb->stats);
 367         tdb_io_init(tdb);
 368         tdb->tdb2.direct_access = 0;
 369         tdb->tdb2.transaction = NULL;
 370         tdb->tdb2.access = NULL;
 371
 372         while (attr) {
 373                 switch (attr->base.attr) {
 374                 case TDB_ATTRIBUTE_HASH:
 375                         tdb->hash_fn = attr->hash.fn;
 376                         tdb->hash_data = attr->hash.data;
 377                         break;
 378                 case TDB_ATTRIBUTE_SEED:
 379                         seed = &attr->seed;
 380                         break;
 381                 case TDB_ATTRIBUTE_OPENHOOK:
 382                         tdb->openhook = attr->openhook.fn;
 383                         tdb->openhook_data = attr->openhook.data;
 384                         break;
 385                 default:
 386                         /* These are set as normal. */
 387                         ecode = tdb_set_attribute(tdb, attr);
 388                         if (ecode != TDB_SUCCESS)
 389                                 goto fail;
 390                 }
 391                 attr = attr->base.next;
 392         }
 393
 394         if (tdb_flags & ~(TDB_INTERNAL | TDB_NOLOCK | TDB_NOMMAP | TDB_CONVERT
 395                           | TDB_NOSYNC | TDB_SEQNUM | TDB_ALLOW_NESTING
 396                           | TDB_RDONLY)) {
 397                 ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 398                                    "tdb_open: unknown flags %u", tdb_flags);
 399                 goto fail;
 400         }
 401
 402         if ((open_flags & O_ACCMODE) == O_WRONLY) {
 403                 ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 404                                    "tdb_open: can't open tdb %s write-only",
 405                                    name);
 406                 goto fail;
 407         }
 408
 409         if ((open_flags & O_ACCMODE) == O_RDONLY) {
 410                 openlock = F_RDLCK;
 411                 tdb->flags |= TDB_RDONLY;
 412         } else {
 413                 if (tdb_flags & TDB_RDONLY) {
 414                         ecode = tdb_logerr(tdb, TDB_ERR_EINVAL,
 415                                            TDB_LOG_USE_ERROR,
 416                                            "tdb_open: can't use TDB_RDONLY"
 417                                            " without O_RDONLY");
 418                         goto fail;
 419                 }
 420                 openlock = F_WRLCK;
 421         }
 422
 423         /* internal databases don't need any of the rest. */
 424         if (tdb->flags & TDB_INTERNAL) {
 425                 tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP);
 426                 ecode = tdb_new_file(tdb);
 427                 if (ecode != TDB_SUCCESS) {
 428                         goto fail;
 429                 }
 430                 tdb->file->fd = -1;
 431                 ecode = tdb_new_database(tdb, seed, &hdr);
 432                 if (ecode != TDB_SUCCESS) {
 433                         goto fail;
 434                 }
 435                 tdb_convert(tdb, &hdr.hash_seed, sizeof(hdr.hash_seed));
 436                 tdb->hash_seed = hdr.hash_seed;
 437                 tdb_ftable_init(tdb);
 438                 return tdb;
 439         }
 440
 441         if (stat(name, &st) != -1)
 442                 tdb->file = find_file(st.st_dev, st.st_ino);
 443
 444         if (!tdb->file) {
 445                 int fd;
 446
 447                 if ((fd = open(name, open_flags, mode)) == -1) {
 448                         /* errno set by open(2) */
 449                         saved_errno = errno;
 450                         tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 451                                    "tdb_open: could not open file %s: %s",
 452                                    name, strerror(errno));
 453                         goto fail_errno;
 454                 }
 455
 456                 /* on exec, don't inherit the fd */
 457                 v = fcntl(fd, F_GETFD, 0);
 458                 fcntl(fd, F_SETFD, v | FD_CLOEXEC);
 459
 460                 if (fstat(fd, &st) == -1) {
 461                         saved_errno = errno;
 462                         tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 463                                    "tdb_open: could not stat open %s: %s",
 464                                    name, strerror(errno));
 465                         close(fd);
 466                         goto fail_errno;
 467                 }
 468
 469                 ecode = tdb_new_file(tdb);
 470                 if (ecode != TDB_SUCCESS) {
 471                         close(fd);
 472                         goto fail;
 473                 }
 474
 475                 tdb->file->fd = fd;
 476                 tdb->file->device = st.st_dev;
 477                 tdb->file->inode = st.st_ino;
 478                 tdb->file->map_ptr = NULL;
 479                 tdb->file->map_size = sizeof(struct tdb_header);
 480         }
 481
 482         /* ensure there is only one process initialising at once */
 483         ecode = tdb_lock_open(tdb, openlock, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
 484         if (ecode != TDB_SUCCESS) {
 485                 saved_errno = errno;
 486                 goto fail_errno;
 487         }
 488
 489         /* call their open hook if they gave us one. */
 490         if (tdb->openhook) {
 491                 ecode = tdb->openhook(tdb->file->fd, tdb->openhook_data);
 492                 if (ecode != TDB_SUCCESS) {
 493                         tdb_logerr(tdb, ecode, TDB_LOG_ERROR,
 494                                    "tdb_open: open hook failed");
 495                         goto fail;
 496                 }
 497                 open_flags |= O_CREAT;
 498         }
 499
 500         /* If they used O_TRUNC, read will return 0. */
 501         rlen = pread(tdb->file->fd, &hdr, sizeof(hdr), 0);
 502         if (rlen == 0 && (open_flags & O_CREAT)) {
 503                 ecode = tdb_new_database(tdb, seed, &hdr);
 504                 if (ecode != TDB_SUCCESS) {
 505                         goto fail;
 506                 }
 507         } else if (rlen < 0) {
 508                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 509                                    "tdb_open: error %s reading %s",
 510                                    strerror(errno), name);
 511                 goto fail;
 512         } else if (rlen < sizeof(hdr)
 513                    || strcmp(hdr.magic_food, TDB_MAGIC_FOOD) != 0) {
 514                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 515                                    "tdb_open: %s is not a tdb file", name);
 516                 goto fail;
 517         }
 518
 519         if (hdr.version != TDB_VERSION) {
 520                 if (hdr.version == bswap_64(TDB_VERSION))
 521                         tdb->flags |= TDB_CONVERT;
 522                 else {
 523                         /* wrong version */
 524                         ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 525                                            "tdb_open:"
 526                                            " %s is unknown version 0x%llx",
 527                                            name, (long long)hdr.version);
 528                         goto fail;
 529                 }
 530         } else if (tdb->flags & TDB_CONVERT) {
 531                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 532                                    "tdb_open:"
 533                                    " %s does not need TDB_CONVERT",
 534                                    name);
 535                 goto fail;
 536         }
 537
 538         tdb_convert(tdb, &hdr, sizeof(hdr));
 539         tdb->hash_seed = hdr.hash_seed;
 540         hash_test = TDB_HASH_MAGIC;
 541         hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
 542         if (hdr.hash_test != hash_test) {
 543                 /* wrong hash variant */
 544                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 545                                    "tdb_open:"
 546                                    " %s uses a different hash function",
 547                                    name);
 548                 goto fail;
 549         }
 550
 551         /* Clear any features we don't understand. */
 552         if ((open_flags & O_ACCMODE) != O_RDONLY) {
 553                 hdr.features_used &= TDB_FEATURE_MASK;
 554                 ecode = tdb_write_convert(tdb, offsetof(struct tdb_header,
 555                                                         features_used),
 556                                           &hdr.features_used,
 557                                           sizeof(hdr.features_used));
 558                 if (ecode != TDB_SUCCESS)
 559                         goto fail;
 560         }
 561
 562         tdb_unlock_open(tdb, openlock);
 563
 564         /* This make sure we have current map_size and mmap. */
 565         ecode = tdb->tdb2.io->oob(tdb, tdb->file->map_size + 1, true);
 566         if (unlikely(ecode != TDB_SUCCESS))
 567                 goto fail;
 568
 569         /* Now it's fully formed, recover if necessary. */
 570         berr = tdb_needs_recovery(tdb);
 571         if (unlikely(berr != false)) {
 572                 if (berr < 0) {
 573                         ecode = berr;
 574                         goto fail;
 575                 }
 576                 ecode = tdb_lock_and_recover(tdb);
 577                 if (ecode != TDB_SUCCESS) {
 578                         goto fail;
 579                 }
 580         }
 581
 582         ecode = tdb_ftable_init(tdb);
 583         if (ecode != TDB_SUCCESS) {
 584                 goto fail;
 585         }
 586
 587         tdb->next = tdbs;
 588         tdbs = tdb;
 589         return tdb;
 590
 591  fail:
 592         /* Map ecode to some logical errno. */
 593         switch (ecode) {
 594         case TDB_ERR_CORRUPT:
 595         case TDB_ERR_IO:
 596                 saved_errno = EIO;
 597                 break;
 598         case TDB_ERR_LOCK:
 599                 saved_errno = EWOULDBLOCK;
 600                 break;
 601         case TDB_ERR_OOM:
 602                 saved_errno = ENOMEM;
 603                 break;
 604         case TDB_ERR_EINVAL:
 605                 saved_errno = EINVAL;
 606                 break;
 607         default:
 608                 saved_errno = EINVAL;
 609                 break;
 610         }
 611
 612 fail_errno:
 613 #ifdef TDB_TRACE
 614         close(tdb->tracefd);
 615 #endif
 616         if (tdb->file) {
 617                 tdb_lock_cleanup(tdb);
 618                 if (--tdb->file->refcnt == 0) {
 619                         assert(tdb->file->num_lockrecs == 0);
 620                         if (tdb->file->map_ptr) {
 621                                 if (tdb->flags & TDB_INTERNAL) {
 622                                         free(tdb->file->map_ptr);
 623                                 } else
 624                                         tdb_munmap(tdb->file);
 625                         }
 626                         if (close(tdb->file->fd) != 0)
 627                                 tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 628                                            "tdb_open: failed to close tdb fd"
 629                                            " on error: %s", strerror(errno));
 630                         free(tdb->file->lockrecs);
 631                         free(tdb->file);
 632                 }
 633         }
 634
 635         free(tdb);
 636         errno = saved_errno;
 637         return NULL;
 638 }
 639
 640 int tdb_close(struct tdb_context *tdb)
 641 {
 642         int ret = 0;
 643         struct tdb_context **i;
 644
 645         tdb_trace(tdb, "tdb_close");
 646
 647         if (tdb->tdb2.transaction) {
 648                 tdb_transaction_cancel(tdb);
 649         }
 650
 651         if (tdb->file->map_ptr) {
 652                 if (tdb->flags & TDB_INTERNAL)
 653                         free(tdb->file->map_ptr);
 654                 else
 655                         tdb_munmap(tdb->file);
 656         }
 657         if (tdb->file) {
 658                 tdb_lock_cleanup(tdb);
 659                 if (--tdb->file->refcnt == 0) {
 660                         ret = close(tdb->file->fd);
 661                         free(tdb->file->lockrecs);
 662                         free(tdb->file);
 663                 }
 664         }
 665
 666         /* Remove from tdbs list */
 667         for (i = &tdbs; *i; i = &(*i)->next) {
 668                 if (*i == tdb) {
 669                         *i = tdb->next;
 670                         break;
 671                 }
 672         }
 673
 674 #ifdef TDB_TRACE
 675         close(tdb->tracefd);
 676 #endif
 677         free(tdb);
 678
 679         return ret;
 680 }
 681
 682 void tdb_foreach_(int (*fn)(struct tdb_context *, void *), void *p)
 683 {
 684         struct tdb_context *i;
 685
 686         for (i = tdbs; i; i = i->next) {
 687                 if (fn(i, p) != 0)
 688                         break;
 689         }
 690 }