-/* The null return. */
-struct tdb_data tdb_null = { .dptr = NULL, .dsize = 0 };
-
-/* all contexts, to ensure no double-opens (fcntl locks don't nest!) */
-static struct tdb_context *tdbs = NULL;
-
-static bool tdb_already_open(dev_t device, ino_t ino)
-{
- struct tdb_context *i;
-
- for (i = tdbs; i; i = i->next) {
- if (i->device == device && i->inode == ino) {
- return true;
- }
- }
-
- return false;
-}
-
-static bool read_all(int fd, void *buf, size_t len)
-{
- while (len) {
- ssize_t ret;
- ret = read(fd, buf, len);
- if (ret < 0)
- return false;
- if (ret == 0) {
- /* ETOOSHORT? */
- errno = EWOULDBLOCK;
- return false;
- }
- buf = (char *)buf + ret;
- len -= ret;
- }
- return true;
-}
-
-static uint64_t random_number(struct tdb_context *tdb)
-{
- int fd;
- uint64_t ret = 0;
- struct timeval now;
-
- fd = open("/dev/urandom", O_RDONLY);
- if (fd >= 0) {
- if (read_all(fd, &ret, sizeof(ret))) {
- close(fd);
- return ret;
- }
- close(fd);
- }
- /* FIXME: Untested! Based on Wikipedia protocol description! */
- fd = open("/dev/egd-pool", O_RDWR);
- if (fd >= 0) {
- /* Command is 1, next byte is size we want to read. */
- char cmd[2] = { 1, sizeof(uint64_t) };
- if (write(fd, cmd, sizeof(cmd)) == sizeof(cmd)) {
- char reply[1 + sizeof(uint64_t)];
- int r = read(fd, reply, sizeof(reply));
- if (r > 1) {
- /* Copy at least some bytes. */
- memcpy(&ret, reply+1, r - 1);
- if (reply[0] == sizeof(uint64_t)
- && r == sizeof(reply)) {
- close(fd);
- return ret;
- }
- }
- }
- close(fd);
- }
-
- /* Fallback: pid and time. */
- gettimeofday(&now, NULL);
- ret = getpid() * 100132289ULL + now.tv_sec * 1000000ULL + now.tv_usec;
- tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
- "tdb_open: random from getpid and time");
- return ret;
-}
-
-struct new_database {
- struct tdb_header hdr;
- struct tdb_freetable ftable;
-};
-
-/* initialise a new database */
-static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb,
- struct tdb_attribute_seed *seed,
- struct tdb_header *hdr)
-{
- /* We make it up in memory, then write it out if not internal */
- struct new_database newdb;
- unsigned int magic_len;
- ssize_t rlen;
- enum TDB_ERROR ecode;
-
- /* Fill in the header */
- newdb.hdr.version = TDB_VERSION;
- if (seed)
- newdb.hdr.hash_seed = seed->seed;
- else
- newdb.hdr.hash_seed = random_number(tdb);
- newdb.hdr.hash_test = TDB_HASH_MAGIC;
- newdb.hdr.hash_test = tdb->khash(&newdb.hdr.hash_test,
- sizeof(newdb.hdr.hash_test),
- newdb.hdr.hash_seed,
- tdb->hash_priv);
- newdb.hdr.recovery = 0;
- memset(newdb.hdr.reserved, 0, sizeof(newdb.hdr.reserved));
- /* Initial hashes are empty. */
- memset(newdb.hdr.hashtable, 0, sizeof(newdb.hdr.hashtable));
-
- /* Free is empty. */
- newdb.hdr.free_table = offsetof(struct new_database, ftable);
- memset(&newdb.ftable, 0, sizeof(newdb.ftable));
- ecode = set_header(NULL, &newdb.ftable.hdr, TDB_FTABLE_MAGIC, 0,
- sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
- sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
- 0);
- if (ecode != TDB_SUCCESS) {
- return ecode;
- }
-
- /* Magic food */
- memset(newdb.hdr.magic_food, 0, sizeof(newdb.hdr.magic_food));
- strcpy(newdb.hdr.magic_food, TDB_MAGIC_FOOD);
-
- /* This creates an endian-converted database, as if read from disk */
- magic_len = sizeof(newdb.hdr.magic_food);
- tdb_convert(tdb,
- (char *)&newdb.hdr + magic_len, sizeof(newdb) - magic_len);
-
- *hdr = newdb.hdr;
-
- if (tdb->flags & TDB_INTERNAL) {
- tdb->map_size = sizeof(newdb);
- tdb->map_ptr = malloc(tdb->map_size);
- if (!tdb->map_ptr) {
- return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
- "tdb_new_database:"
- " failed to allocate");
- }
- memcpy(tdb->map_ptr, &newdb, tdb->map_size);
- return TDB_SUCCESS;
- }
- if (lseek(tdb->fd, 0, SEEK_SET) == -1) {
- return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_new_database:"
- " failed to seek: %s", strerror(errno));
- }
-
- if (ftruncate(tdb->fd, 0) == -1) {
- return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_new_database:"
- " failed to truncate: %s", strerror(errno));
- }
-
- rlen = write(tdb->fd, &newdb, sizeof(newdb));
- if (rlen != sizeof(newdb)) {
- if (rlen >= 0)
- errno = ENOSPC;
- return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_new_database: %zi writing header: %s",
- rlen, strerror(errno));
- }
- return TDB_SUCCESS;
-}
-
-struct tdb_context *tdb_open(const char *name, int tdb_flags,
- int open_flags, mode_t mode,
- union tdb_attribute *attr)
-{
- struct tdb_context *tdb;
- struct stat st;
- int saved_errno = 0;
- uint64_t hash_test;
- unsigned v;
- ssize_t rlen;
- struct tdb_header hdr;
- struct tdb_attribute_seed *seed = NULL;
- tdb_bool_err berr;
- enum TDB_ERROR ecode;
-
- tdb = malloc(sizeof(*tdb));
- if (!tdb) {
- /* Can't log this */
- errno = ENOMEM;
- return NULL;
- }
- tdb->name = NULL;
- tdb->map_ptr = NULL;
- tdb->direct_access = 0;
- tdb->fd = -1;
- tdb->map_size = sizeof(struct tdb_header);
- tdb->flags = tdb_flags;
- tdb->logfn = NULL;
- tdb->transaction = NULL;
- tdb->stats = NULL;
- tdb->access = NULL;
- tdb_hash_init(tdb);
- tdb_io_init(tdb);
- tdb_lock_init(tdb);
-
- while (attr) {
- switch (attr->base.attr) {
- case TDB_ATTRIBUTE_LOG:
- tdb->logfn = attr->log.log_fn;
- tdb->log_private = attr->log.log_private;
- break;
- case TDB_ATTRIBUTE_HASH:
- tdb->khash = attr->hash.hash_fn;
- tdb->hash_priv = attr->hash.hash_private;
- break;
- case TDB_ATTRIBUTE_SEED:
- seed = &attr->seed;
- break;
- case TDB_ATTRIBUTE_STATS:
- tdb->stats = &attr->stats;
- /* They have stats we don't know about? Tell them. */
- if (tdb->stats->size > sizeof(attr->stats))
- tdb->stats->size = sizeof(attr->stats);
- break;
- default:
- ecode = tdb_logerr(tdb, TDB_ERR_EINVAL,
- TDB_LOG_USE_ERROR,
- "tdb_open:"
- " unknown attribute type %u",
- attr->base.attr);
- goto fail;
- }
- attr = attr->base.next;
- }
-
- if ((open_flags & O_ACCMODE) == O_WRONLY) {
- ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
- "tdb_open: can't open tdb %s write-only",
- name);
- goto fail;
- }
-
- if ((open_flags & O_ACCMODE) == O_RDONLY) {
- tdb->read_only = true;
- tdb->mmap_flags = PROT_READ;
- } else {
- tdb->read_only = false;
- tdb->mmap_flags = PROT_READ | PROT_WRITE;
- }
-
- /* internal databases don't need any of the rest. */
- if (tdb->flags & TDB_INTERNAL) {
- tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP);
- ecode = tdb_new_database(tdb, seed, &hdr);
- if (ecode != TDB_SUCCESS) {
- goto fail;
- }
- tdb_convert(tdb, &hdr.hash_seed, sizeof(hdr.hash_seed));
- tdb->hash_seed = hdr.hash_seed;
- tdb_ftable_init(tdb);
- return tdb;
- }
-
- if ((tdb->fd = open(name, open_flags, mode)) == -1) {
- /* errno set by open(2) */
- saved_errno = errno;
- ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_open: could not open file %s: %s",
- name, strerror(errno));
- goto fail;
- }
-
- /* on exec, don't inherit the fd */
- v = fcntl(tdb->fd, F_GETFD, 0);
- fcntl(tdb->fd, F_SETFD, v | FD_CLOEXEC);
-
- /* ensure there is only one process initialising at once */
- ecode = tdb_lock_open(tdb, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
- if (ecode != TDB_SUCCESS) {
- goto fail;
- }
-
- /* If they used O_TRUNC, read will return 0. */
- rlen = read(tdb->fd, &hdr, sizeof(hdr));
- if (rlen == 0 && (open_flags & O_CREAT)) {
- ecode = tdb_new_database(tdb, seed, &hdr);
- if (ecode != TDB_SUCCESS) {
- goto fail;
- }
- } else if (rlen < 0) {
- ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_open: error %s reading %s",
- strerror(errno), name);
- goto fail;
- } else if (rlen < sizeof(hdr)
- || strcmp(hdr.magic_food, TDB_MAGIC_FOOD) != 0) {
- ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_open: %s is not a tdb file", name);
- goto fail;
- }
-
- if (hdr.version != TDB_VERSION) {
- if (hdr.version == bswap_64(TDB_VERSION))
- tdb->flags |= TDB_CONVERT;
- else {
- /* wrong version */
- ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_open:"
- " %s is unknown version 0x%llx",
- name, (long long)hdr.version);
- goto fail;
- }
- }
-
- tdb_convert(tdb, &hdr, sizeof(hdr));
- tdb->hash_seed = hdr.hash_seed;
- hash_test = TDB_HASH_MAGIC;
- hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
- if (hdr.hash_test != hash_test) {
- /* wrong hash variant */
- ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_open:"
- " %s uses a different hash function",
- name);
- goto fail;
- }
-
- if (fstat(tdb->fd, &st) == -1) {
- saved_errno = errno;
- ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_open: could not stat open %s: %s",
- name, strerror(errno));
- goto fail;
- }
-
- /* Is it already in the open list? If so, fail. */
- if (tdb_already_open(st.st_dev, st.st_ino)) {
- /* FIXME */
- ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_USE_ERROR,
- "tdb_open: %s (%d,%d) is already open"
- " in this process",
- name, (int)st.st_dev, (int)st.st_ino);
- goto fail;
- }
-
- tdb->name = strdup(name);
- if (!tdb->name) {
- ecode = tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
- "tdb_open: failed to allocate name");
- goto fail;
- }
-
- tdb->device = st.st_dev;
- tdb->inode = st.st_ino;
- tdb_unlock_open(tdb);
-
- /* This make sure we have current map_size and mmap. */
- tdb->methods->oob(tdb, tdb->map_size + 1, true);
-
- /* Now it's fully formed, recover if necessary. */
- berr = tdb_needs_recovery(tdb);
- if (unlikely(berr != false)) {
- if (berr < 0) {
- ecode = berr;
- goto fail;
- }
- ecode = tdb_lock_and_recover(tdb);
- if (ecode != TDB_SUCCESS) {
- goto fail;
- }
- }
-
- ecode = tdb_ftable_init(tdb);
- if (ecode != TDB_SUCCESS) {
- goto fail;
- }
-
- tdb->next = tdbs;
- tdbs = tdb;
- return tdb;
-
- fail:
- /* Map ecode to some logical errno. */
- if (!saved_errno) {
- switch (ecode) {
- case TDB_ERR_CORRUPT:
- case TDB_ERR_IO:
- saved_errno = EIO;
- break;
- case TDB_ERR_LOCK:
- saved_errno = EWOULDBLOCK;
- break;
- case TDB_ERR_OOM:
- saved_errno = ENOMEM;
- break;
- case TDB_ERR_EINVAL:
- saved_errno = EINVAL;
- break;
- default:
- saved_errno = EINVAL;
- break;
- }
- }
-
-#ifdef TDB_TRACE
- close(tdb->tracefd);
-#endif
- if (tdb->map_ptr) {
- if (tdb->flags & TDB_INTERNAL) {
- free(tdb->map_ptr);
- } else
- tdb_munmap(tdb);
- }
- free(tdb->lockrecs);
- free((char *)tdb->name);
- if (tdb->fd != -1)
- if (close(tdb->fd) != 0)
- tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
- "tdb_open: failed to close tdb->fd"
- " on error: %s", strerror(errno));
- free(tdb);
- errno = saved_errno;
- return NULL;
-}
-