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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         case TDB_ATTRIBUTE_TDB1_HASHSIZE:
 213                 return tdb->last_error
 214                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 215                                      TDB_LOG_USE_ERROR,
 216                                      "tdb_set_attribute:"
 217                                      " cannot set %s after opening",
 218                                      attr->base.attr == TDB_ATTRIBUTE_HASH
 219                                      ? "TDB_ATTRIBUTE_HASH"
 220                                      : attr->base.attr == TDB_ATTRIBUTE_SEED
 221                                      ? "TDB_ATTRIBUTE_SEED"
 222                                      : attr->base.attr == TDB_ATTRIBUTE_OPENHOOK
 223                                      ? "TDB_ATTRIBUTE_OPENHOOK"
 224                                      : "TDB_ATTRIBUTE_TDB1_HASHSIZE");
 225         case TDB_ATTRIBUTE_STATS:
 226                 return tdb->last_error
 227                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 228                                      TDB_LOG_USE_ERROR,
 229                                      "tdb_set_attribute:"
 230                                      " cannot set TDB_ATTRIBUTE_STATS");
 231         case TDB_ATTRIBUTE_FLOCK:
 232                 tdb->lock_fn = attr->flock.lock;
 233                 tdb->unlock_fn = attr->flock.unlock;
 234                 tdb->lock_data = attr->flock.data;
 235                 break;
 236         default:
 237                 return tdb->last_error
 238                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 239                                      TDB_LOG_USE_ERROR,
 240                                      "tdb_set_attribute:"
 241                                      " unknown attribute type %u",
 242                                      attr->base.attr);
 243         }
 244         return TDB_SUCCESS;
 245 }
 246
 247 enum TDB_ERROR tdb_get_attribute(struct tdb_context *tdb,
 248                                  union tdb_attribute *attr)
 249 {
 250         switch (attr->base.attr) {
 251         case TDB_ATTRIBUTE_LOG:
 252                 if (!tdb->log_fn)
 253                         return tdb->last_error = TDB_ERR_NOEXIST;
 254                 attr->log.fn = tdb->log_fn;
 255                 attr->log.data = tdb->log_data;
 256                 break;
 257         case TDB_ATTRIBUTE_HASH:
 258                 attr->hash.fn = tdb->hash_fn;
 259                 attr->hash.data = tdb->hash_data;
 260                 break;
 261         case TDB_ATTRIBUTE_SEED:
 262                 attr->seed.seed = tdb->hash_seed;
 263                 break;
 264         case TDB_ATTRIBUTE_OPENHOOK:
 265                 if (!tdb->openhook)
 266                         return tdb->last_error = TDB_ERR_NOEXIST;
 267                 attr->openhook.fn = tdb->openhook;
 268                 attr->openhook.data = tdb->openhook_data;
 269                 break;
 270         case TDB_ATTRIBUTE_STATS: {
 271                 size_t size = attr->stats.size;
 272                 if (size > tdb->stats.size)
 273                         size = tdb->stats.size;
 274                 memcpy(&attr->stats, &tdb->stats, size);
 275                 break;
 276         }
 277         case TDB_ATTRIBUTE_FLOCK:
 278                 attr->flock.lock = tdb->lock_fn;
 279                 attr->flock.unlock = tdb->unlock_fn;
 280                 attr->flock.data = tdb->lock_data;
 281                 break;
 282         case TDB_ATTRIBUTE_TDB1_HASHSIZE:
 283                 if (!(tdb->flags & TDB_VERSION1))
 284                         return tdb->last_error
 285                                 = tdb_logerr(tdb, TDB_ERR_EINVAL,
 286                                              TDB_LOG_USE_ERROR,
 287                                      "tdb_get_attribute:"
 288                                      " cannot get TDB_ATTRIBUTE_TDB1_HASHSIZE"
 289                                      " on TDB2 tdb.");
 290                 attr->tdb1_hashsize.hsize = tdb->tdb1.header.hash_size;
 291                 break;
 292         default:
 293                 return tdb->last_error
 294                         = tdb_logerr(tdb, TDB_ERR_EINVAL,
 295                                      TDB_LOG_USE_ERROR,
 296                                      "tdb_get_attribute:"
 297                                      " unknown attribute type %u",
 298                                      attr->base.attr);
 299         }
 300         attr->base.next = NULL;
 301         return TDB_SUCCESS;
 302 }
 303
 304 void tdb_unset_attribute(struct tdb_context *tdb,
 305                          enum tdb_attribute_type type)
 306 {
 307         switch (type) {
 308         case TDB_ATTRIBUTE_LOG:
 309                 tdb->log_fn = NULL;
 310                 break;
 311         case TDB_ATTRIBUTE_OPENHOOK:
 312                 tdb->openhook = NULL;
 313                 break;
 314         case TDB_ATTRIBUTE_HASH:
 315         case TDB_ATTRIBUTE_SEED:
 316         case TDB_ATTRIBUTE_TDB1_HASHSIZE:
 317                 tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 318                            "tdb_unset_attribute: cannot unset %s after opening",
 319                            type == TDB_ATTRIBUTE_HASH
 320                            ? "TDB_ATTRIBUTE_HASH"
 321                            : type == TDB_ATTRIBUTE_SEED
 322                            ? "TDB_ATTRIBUTE_SEED"
 323                            : "TDB_ATTRIBUTE_TDB1_HASHSIZE");
 324                 break;
 325         case TDB_ATTRIBUTE_STATS:
 326                 tdb_logerr(tdb, TDB_ERR_EINVAL,
 327                            TDB_LOG_USE_ERROR,
 328                            "tdb_unset_attribute:"
 329                            "cannot unset TDB_ATTRIBUTE_STATS");
 330                 break;
 331         case TDB_ATTRIBUTE_FLOCK:
 332                 tdb->lock_fn = tdb_fcntl_lock;
 333                 tdb->unlock_fn = tdb_fcntl_unlock;
 334                 break;
 335         default:
 336                 tdb_logerr(tdb, TDB_ERR_EINVAL,
 337                            TDB_LOG_USE_ERROR,
 338                            "tdb_unset_attribute: unknown attribute type %u",
 339                            type);
 340         }
 341 }
 342
 343 struct tdb_context *tdb_open(const char *name, int tdb_flags,
 344                              int open_flags, mode_t mode,
 345                              union tdb_attribute *attr)
 346 {
 347         struct tdb_context *tdb;
 348         struct stat st;
 349         int saved_errno = 0;
 350         uint64_t hash_test;
 351         unsigned v;
 352         ssize_t rlen;
 353         struct tdb_header hdr;
 354         struct tdb_attribute_seed *seed = NULL;
 355         struct tdb_attribute_tdb1_hashsize *hsize_attr = NULL;
 356         tdb_bool_err berr;
 357         enum TDB_ERROR ecode;
 358         int openlock;
 359
 360         tdb = malloc(sizeof(*tdb) + (name ? strlen(name) + 1 : 0));
 361         if (!tdb) {
 362                 /* Can't log this */
 363                 errno = ENOMEM;
 364                 return NULL;
 365         }
 366         /* Set name immediately for logging functions. */
 367         if (name) {
 368                 tdb->name = strcpy((char *)(tdb + 1), name);
 369         } else {
 370                 tdb->name = NULL;
 371         }
 372         tdb->flags = tdb_flags;
 373         tdb->log_fn = NULL;
 374         tdb->open_flags = open_flags;
 375         tdb->last_error = TDB_SUCCESS;
 376         tdb->file = NULL;
 377         tdb->openhook = NULL;
 378         tdb->lock_fn = tdb_fcntl_lock;
 379         tdb->unlock_fn = tdb_fcntl_unlock;
 380         tdb->hash_fn = tdb_jenkins_hash;
 381         memset(&tdb->stats, 0, sizeof(tdb->stats));
 382         tdb->stats.base.attr = TDB_ATTRIBUTE_STATS;
 383         tdb->stats.size = sizeof(tdb->stats);
 384         tdb_io_init(tdb);
 385         tdb->tdb2.direct_access = 0;
 386         tdb->tdb2.transaction = NULL;
 387         tdb->tdb2.access = NULL;
 388
 389         while (attr) {
 390                 switch (attr->base.attr) {
 391                 case TDB_ATTRIBUTE_HASH:
 392                         tdb->hash_fn = attr->hash.fn;
 393                         tdb->hash_data = attr->hash.data;
 394                         break;
 395                 case TDB_ATTRIBUTE_SEED:
 396                         seed = &attr->seed;
 397                         break;
 398                 case TDB_ATTRIBUTE_OPENHOOK:
 399                         tdb->openhook = attr->openhook.fn;
 400                         tdb->openhook_data = attr->openhook.data;
 401                         break;
 402                 case TDB_ATTRIBUTE_TDB1_HASHSIZE:
 403                         hsize_attr = &attr->tdb1_hashsize;
 404                         break;
 405                 default:
 406                         /* These are set as normal. */
 407                         ecode = tdb_set_attribute(tdb, attr);
 408                         if (ecode != TDB_SUCCESS)
 409                                 goto fail;
 410                 }
 411                 attr = attr->base.next;
 412         }
 413
 414         if (tdb_flags & ~(TDB_INTERNAL | TDB_NOLOCK | TDB_NOMMAP | TDB_CONVERT
 415                           | TDB_NOSYNC | TDB_SEQNUM | TDB_ALLOW_NESTING
 416                           | TDB_RDONLY)) {
 417                 ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 418                                    "tdb_open: unknown flags %u", tdb_flags);
 419                 goto fail;
 420         }
 421
 422         if (hsize_attr) {
 423                 if (!(tdb_flags & TDB_VERSION1) ||
 424                     (!(tdb_flags & TDB_INTERNAL) && !(open_flags & O_CREAT))) {
 425                         ecode = tdb_logerr(tdb, TDB_ERR_EINVAL,
 426                                            TDB_LOG_USE_ERROR,
 427                                            "tdb_open: can only use"
 428                                            " TDB_ATTRIBUTE_TDB1_HASHSIZE when"
 429                                            " creating a TDB_VERSION1 tdb");
 430                         goto fail;
 431                 }
 432         }
 433
 434         if ((open_flags & O_ACCMODE) == O_WRONLY) {
 435                 ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
 436                                    "tdb_open: can't open tdb %s write-only",
 437                                    name);
 438                 goto fail;
 439         }
 440
 441         if ((open_flags & O_ACCMODE) == O_RDONLY) {
 442                 openlock = F_RDLCK;
 443                 tdb->flags |= TDB_RDONLY;
 444         } else {
 445                 if (tdb_flags & TDB_RDONLY) {
 446                         ecode = tdb_logerr(tdb, TDB_ERR_EINVAL,
 447                                            TDB_LOG_USE_ERROR,
 448                                            "tdb_open: can't use TDB_RDONLY"
 449                                            " without O_RDONLY");
 450                         goto fail;
 451                 }
 452                 openlock = F_WRLCK;
 453         }
 454
 455         /* internal databases don't need any of the rest. */
 456         if (tdb->flags & TDB_INTERNAL) {
 457                 tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP);
 458                 ecode = tdb_new_file(tdb);
 459                 if (ecode != TDB_SUCCESS) {
 460                         goto fail;
 461                 }
 462                 tdb->file->fd = -1;
 463                 ecode = tdb_new_database(tdb, seed, &hdr);
 464                 if (ecode != TDB_SUCCESS) {
 465                         goto fail;
 466                 }
 467                 tdb_convert(tdb, &hdr.hash_seed, sizeof(hdr.hash_seed));
 468                 tdb->hash_seed = hdr.hash_seed;
 469                 tdb_ftable_init(tdb);
 470                 return tdb;
 471         }
 472
 473         if (stat(name, &st) != -1)
 474                 tdb->file = find_file(st.st_dev, st.st_ino);
 475
 476         if (!tdb->file) {
 477                 int fd;
 478
 479                 if ((fd = open(name, open_flags, mode)) == -1) {
 480                         /* errno set by open(2) */
 481                         saved_errno = errno;
 482                         tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 483                                    "tdb_open: could not open file %s: %s",
 484                                    name, strerror(errno));
 485                         goto fail_errno;
 486                 }
 487
 488                 /* on exec, don't inherit the fd */
 489                 v = fcntl(fd, F_GETFD, 0);
 490                 fcntl(fd, F_SETFD, v | FD_CLOEXEC);
 491
 492                 if (fstat(fd, &st) == -1) {
 493                         saved_errno = errno;
 494                         tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 495                                    "tdb_open: could not stat open %s: %s",
 496                                    name, strerror(errno));
 497                         close(fd);
 498                         goto fail_errno;
 499                 }
 500
 501                 ecode = tdb_new_file(tdb);
 502                 if (ecode != TDB_SUCCESS) {
 503                         close(fd);
 504                         goto fail;
 505                 }
 506
 507                 tdb->file->fd = fd;
 508                 tdb->file->device = st.st_dev;
 509                 tdb->file->inode = st.st_ino;
 510                 tdb->file->map_ptr = NULL;
 511                 tdb->file->map_size = sizeof(struct tdb_header);
 512         }
 513
 514         /* ensure there is only one process initialising at once */
 515         ecode = tdb_lock_open(tdb, openlock, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
 516         if (ecode != TDB_SUCCESS) {
 517                 saved_errno = errno;
 518                 goto fail_errno;
 519         }
 520
 521         /* call their open hook if they gave us one. */
 522         if (tdb->openhook) {
 523                 ecode = tdb->openhook(tdb->file->fd, tdb->openhook_data);
 524                 if (ecode != TDB_SUCCESS) {
 525                         tdb_logerr(tdb, ecode, TDB_LOG_ERROR,
 526                                    "tdb_open: open hook failed");
 527                         goto fail;
 528                 }
 529                 open_flags |= O_CREAT;
 530         }
 531
 532         /* If they used O_TRUNC, read will return 0. */
 533         rlen = pread(tdb->file->fd, &hdr, sizeof(hdr), 0);
 534         if (rlen == 0 && (open_flags & O_CREAT)) {
 535                 ecode = tdb_new_database(tdb, seed, &hdr);
 536                 if (ecode != TDB_SUCCESS) {
 537                         goto fail;
 538                 }
 539         } else if (rlen < 0) {
 540                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 541                                    "tdb_open: error %s reading %s",
 542                                    strerror(errno), name);
 543                 goto fail;
 544         } else if (rlen < sizeof(hdr)
 545                    || strcmp(hdr.magic_food, TDB_MAGIC_FOOD) != 0) {
 546                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 547                                    "tdb_open: %s is not a tdb file", name);
 548                 goto fail;
 549         }
 550
 551         if (hdr.version != TDB_VERSION) {
 552                 if (hdr.version == bswap_64(TDB_VERSION))
 553                         tdb->flags |= TDB_CONVERT;
 554                 else {
 555                         /* wrong version */
 556                         ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 557                                            "tdb_open:"
 558                                            " %s is unknown version 0x%llx",
 559                                            name, (long long)hdr.version);
 560                         goto fail;
 561                 }
 562         } else if (tdb->flags & TDB_CONVERT) {
 563                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 564                                    "tdb_open:"
 565                                    " %s does not need TDB_CONVERT",
 566                                    name);
 567                 goto fail;
 568         }
 569
 570         tdb_convert(tdb, &hdr, sizeof(hdr));
 571         tdb->hash_seed = hdr.hash_seed;
 572         hash_test = TDB_HASH_MAGIC;
 573         hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
 574         if (hdr.hash_test != hash_test) {
 575                 /* wrong hash variant */
 576                 ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 577                                    "tdb_open:"
 578                                    " %s uses a different hash function",
 579                                    name);
 580                 goto fail;
 581         }
 582
 583         /* Clear any features we don't understand. */
 584         if ((open_flags & O_ACCMODE) != O_RDONLY) {
 585                 hdr.features_used &= TDB_FEATURE_MASK;
 586                 ecode = tdb_write_convert(tdb, offsetof(struct tdb_header,
 587                                                         features_used),
 588                                           &hdr.features_used,
 589                                           sizeof(hdr.features_used));
 590                 if (ecode != TDB_SUCCESS)
 591                         goto fail;
 592         }
 593
 594         tdb_unlock_open(tdb, openlock);
 595
 596         /* This make sure we have current map_size and mmap. */
 597         ecode = tdb->tdb2.io->oob(tdb, tdb->file->map_size + 1, true);
 598         if (unlikely(ecode != TDB_SUCCESS))
 599                 goto fail;
 600
 601         /* Now it's fully formed, recover if necessary. */
 602         berr = tdb_needs_recovery(tdb);
 603         if (unlikely(berr != false)) {
 604                 if (berr < 0) {
 605                         ecode = berr;
 606                         goto fail;
 607                 }
 608                 ecode = tdb_lock_and_recover(tdb);
 609                 if (ecode != TDB_SUCCESS) {
 610                         goto fail;
 611                 }
 612         }
 613
 614         ecode = tdb_ftable_init(tdb);
 615         if (ecode != TDB_SUCCESS) {
 616                 goto fail;
 617         }
 618
 619         tdb->next = tdbs;
 620         tdbs = tdb;
 621         return tdb;
 622
 623  fail:
 624         /* Map ecode to some logical errno. */
 625         switch (ecode) {
 626         case TDB_ERR_CORRUPT:
 627         case TDB_ERR_IO:
 628                 saved_errno = EIO;
 629                 break;
 630         case TDB_ERR_LOCK:
 631                 saved_errno = EWOULDBLOCK;
 632                 break;
 633         case TDB_ERR_OOM:
 634                 saved_errno = ENOMEM;
 635                 break;
 636         case TDB_ERR_EINVAL:
 637                 saved_errno = EINVAL;
 638                 break;
 639         default:
 640                 saved_errno = EINVAL;
 641                 break;
 642         }
 643
 644 fail_errno:
 645 #ifdef TDB_TRACE
 646         close(tdb->tracefd);
 647 #endif
 648         if (tdb->file) {
 649                 tdb_lock_cleanup(tdb);
 650                 if (--tdb->file->refcnt == 0) {
 651                         assert(tdb->file->num_lockrecs == 0);
 652                         if (tdb->file->map_ptr) {
 653                                 if (tdb->flags & TDB_INTERNAL) {
 654                                         free(tdb->file->map_ptr);
 655                                 } else
 656                                         tdb_munmap(tdb->file);
 657                         }
 658                         if (close(tdb->file->fd) != 0)
 659                                 tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 660                                            "tdb_open: failed to close tdb fd"
 661                                            " on error: %s", strerror(errno));
 662                         free(tdb->file->lockrecs);
 663                         free(tdb->file);
 664                 }
 665         }
 666
 667         free(tdb);
 668         errno = saved_errno;
 669         return NULL;
 670 }
 671
 672 int tdb_close(struct tdb_context *tdb)
 673 {
 674         int ret = 0;
 675         struct tdb_context **i;
 676
 677         tdb_trace(tdb, "tdb_close");
 678
 679         if (tdb->tdb2.transaction) {
 680                 tdb_transaction_cancel(tdb);
 681         }
 682
 683         if (tdb->file->map_ptr) {
 684                 if (tdb->flags & TDB_INTERNAL)
 685                         free(tdb->file->map_ptr);
 686                 else
 687                         tdb_munmap(tdb->file);
 688         }
 689         if (tdb->file) {
 690                 tdb_lock_cleanup(tdb);
 691                 if (--tdb->file->refcnt == 0) {
 692                         ret = close(tdb->file->fd);
 693                         free(tdb->file->lockrecs);
 694                         free(tdb->file);
 695                 }
 696         }
 697
 698         /* Remove from tdbs list */
 699         for (i = &tdbs; *i; i = &(*i)->next) {
 700                 if (*i == tdb) {
 701                         *i = tdb->next;
 702                         break;
 703                 }
 704         }
 705
 706 #ifdef TDB_TRACE
 707         close(tdb->tracefd);
 708 #endif
 709         free(tdb);
 710
 711         return ret;
 712 }
 713
 714 void tdb_foreach_(int (*fn)(struct tdb_context *, void *), void *p)
 715 {
 716         struct tdb_context *i;
 717
 718         for (i = tdbs; i; i = i->next) {
 719                 if (fn(i, p) != 0)
 720                         break;
 721         }
 722 }