+#include "private.h"
+
+/* 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;
+ newdb.hdr.features_used = newdb.hdr.features_offered = TDB_FEATURE_MASK;
+ 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 (tdb_flags & ~(TDB_INTERNAL | TDB_NOLOCK | TDB_NOMMAP | TDB_CONVERT
+ | TDB_NOSYNC)) {
+ ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
+ "tdb_open: unknown flags %u", tdb_flags);
+ goto fail;
+ }
+
+ 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;
+ }
+
+ /* Clear any features we don't understand. */
+ if ((open_flags & O_ACCMODE) != O_RDONLY) {
+ hdr.features_used &= TDB_FEATURE_MASK;
+ if (tdb_write_convert(tdb, offsetof(struct tdb_header,
+ features_used),
+ &hdr.features_used,
+ sizeof(hdr.features_used)) == -1)
+ 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;
+}
+
+int tdb_close(struct tdb_context *tdb)
+{
+ struct tdb_context **i;
+ int ret = 0;
+
+ tdb_trace(tdb, "tdb_close");
+
+ if (tdb->transaction) {
+ tdb_transaction_cancel(tdb);
+ }
+
+ if (tdb->map_ptr) {
+ if (tdb->flags & TDB_INTERNAL)
+ free(tdb->map_ptr);
+ else
+ tdb_munmap(tdb);
+ }
+ free((char *)tdb->name);
+ if (tdb->fd != -1) {
+ ret = close(tdb->fd);
+ tdb->fd = -1;
+ }
+ free(tdb->lockrecs);
+
+ /* Remove from contexts list */
+ for (i = &tdbs; *i; i = &(*i)->next) {
+ if (*i == tdb) {
+ *i = tdb->next;
+ break;
+ }
+ }
+
+#ifdef TDB_TRACE
+ close(tdb->tracefd);
+#endif
+ free(tdb);
+
+ return ret;
+}