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-rw-r--r--lib/tdb2/tdb.c486
1 files changed, 486 insertions, 0 deletions
diff --git a/lib/tdb2/tdb.c b/lib/tdb2/tdb.c
new file mode 100644
index 0000000000..753ccb0c8b
--- /dev/null
+++ b/lib/tdb2/tdb.c
@@ -0,0 +1,486 @@
+#include "private.h"
+#ifndef _SAMBA_BUILD_
+#include <ccan/asprintf/asprintf.h>
+#include <stdarg.h>
+#endif
+
+static enum TDB_ERROR update_rec_hdr(struct tdb_context *tdb,
+ tdb_off_t off,
+ tdb_len_t keylen,
+ tdb_len_t datalen,
+ struct tdb_used_record *rec,
+ uint64_t h)
+{
+ uint64_t dataroom = rec_data_length(rec) + rec_extra_padding(rec);
+ enum TDB_ERROR ecode;
+
+ ecode = set_header(tdb, rec, TDB_USED_MAGIC, keylen, datalen,
+ keylen + dataroom, h);
+ if (ecode == TDB_SUCCESS) {
+ ecode = tdb_write_convert(tdb, off, rec, sizeof(*rec));
+ }
+ return ecode;
+}
+
+static enum TDB_ERROR replace_data(struct tdb_context *tdb,
+ struct hash_info *h,
+ struct tdb_data key, struct tdb_data dbuf,
+ tdb_off_t old_off, tdb_len_t old_room,
+ bool growing)
+{
+ tdb_off_t new_off;
+ enum TDB_ERROR ecode;
+
+ /* Allocate a new record. */
+ new_off = alloc(tdb, key.dsize, dbuf.dsize, h->h, TDB_USED_MAGIC,
+ growing);
+ if (TDB_OFF_IS_ERR(new_off)) {
+ return new_off;
+ }
+
+ /* We didn't like the existing one: remove it. */
+ if (old_off) {
+ tdb->stats.frees++;
+ ecode = add_free_record(tdb, old_off,
+ sizeof(struct tdb_used_record)
+ + key.dsize + old_room,
+ TDB_LOCK_WAIT, true);
+ if (ecode == TDB_SUCCESS)
+ ecode = replace_in_hash(tdb, h, new_off);
+ } else {
+ ecode = add_to_hash(tdb, h, new_off);
+ }
+ if (ecode != TDB_SUCCESS) {
+ return ecode;
+ }
+
+ new_off += sizeof(struct tdb_used_record);
+ ecode = tdb->methods->twrite(tdb, new_off, key.dptr, key.dsize);
+ if (ecode != TDB_SUCCESS) {
+ return ecode;
+ }
+
+ new_off += key.dsize;
+ ecode = tdb->methods->twrite(tdb, new_off, dbuf.dptr, dbuf.dsize);
+ if (ecode != TDB_SUCCESS) {
+ return ecode;
+ }
+
+ if (tdb->flags & TDB_SEQNUM)
+ tdb_inc_seqnum(tdb);
+
+ return TDB_SUCCESS;
+}
+
+static enum TDB_ERROR update_data(struct tdb_context *tdb,
+ tdb_off_t off,
+ struct tdb_data dbuf,
+ tdb_len_t extra)
+{
+ enum TDB_ERROR ecode;
+
+ ecode = tdb->methods->twrite(tdb, off, dbuf.dptr, dbuf.dsize);
+ if (ecode == TDB_SUCCESS && extra) {
+ /* Put a zero in; future versions may append other data. */
+ ecode = tdb->methods->twrite(tdb, off + dbuf.dsize, "", 1);
+ }
+ if (tdb->flags & TDB_SEQNUM)
+ tdb_inc_seqnum(tdb);
+
+ return ecode;
+}
+
+enum TDB_ERROR tdb_store(struct tdb_context *tdb,
+ struct tdb_data key, struct tdb_data dbuf, int flag)
+{
+ struct hash_info h;
+ tdb_off_t off;
+ tdb_len_t old_room = 0;
+ struct tdb_used_record rec;
+ enum TDB_ERROR ecode;
+
+ off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
+ if (TDB_OFF_IS_ERR(off)) {
+ return tdb->last_error = off;
+ }
+
+ /* Now we have lock on this hash bucket. */
+ if (flag == TDB_INSERT) {
+ if (off) {
+ ecode = TDB_ERR_EXISTS;
+ goto out;
+ }
+ } else {
+ if (off) {
+ old_room = rec_data_length(&rec)
+ + rec_extra_padding(&rec);
+ if (old_room >= dbuf.dsize) {
+ /* Can modify in-place. Easy! */
+ ecode = update_rec_hdr(tdb, off,
+ key.dsize, dbuf.dsize,
+ &rec, h.h);
+ if (ecode != TDB_SUCCESS) {
+ goto out;
+ }
+ ecode = update_data(tdb,
+ off + sizeof(rec)
+ + key.dsize, dbuf,
+ old_room - dbuf.dsize);
+ if (ecode != TDB_SUCCESS) {
+ goto out;
+ }
+ tdb_unlock_hashes(tdb, h.hlock_start,
+ h.hlock_range, F_WRLCK);
+ return tdb->last_error = TDB_SUCCESS;
+ }
+ } else {
+ if (flag == TDB_MODIFY) {
+ /* if the record doesn't exist and we
+ are in TDB_MODIFY mode then we should fail
+ the store */
+ ecode = TDB_ERR_NOEXIST;
+ goto out;
+ }
+ }
+ }
+
+ /* If we didn't use the old record, this implies we're growing. */
+ ecode = replace_data(tdb, &h, key, dbuf, off, old_room, off);
+out:
+ tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
+ return tdb->last_error = ecode;
+}
+
+enum TDB_ERROR tdb_append(struct tdb_context *tdb,
+ struct tdb_data key, struct tdb_data dbuf)
+{
+ struct hash_info h;
+ tdb_off_t off;
+ struct tdb_used_record rec;
+ tdb_len_t old_room = 0, old_dlen;
+ unsigned char *newdata;
+ struct tdb_data new_dbuf;
+ enum TDB_ERROR ecode;
+
+ off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
+ if (TDB_OFF_IS_ERR(off)) {
+ return tdb->last_error = off;
+ }
+
+ if (off) {
+ old_dlen = rec_data_length(&rec);
+ old_room = old_dlen + rec_extra_padding(&rec);
+
+ /* Fast path: can append in place. */
+ if (rec_extra_padding(&rec) >= dbuf.dsize) {
+ ecode = update_rec_hdr(tdb, off, key.dsize,
+ old_dlen + dbuf.dsize, &rec,
+ h.h);
+ if (ecode != TDB_SUCCESS) {
+ goto out;
+ }
+
+ off += sizeof(rec) + key.dsize + old_dlen;
+ ecode = update_data(tdb, off, dbuf,
+ rec_extra_padding(&rec));
+ goto out;
+ }
+
+ /* Slow path. */
+ newdata = malloc(key.dsize + old_dlen + dbuf.dsize);
+ if (!newdata) {
+ ecode = tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
+ "tdb_append:"
+ " failed to allocate %zu bytes",
+ (size_t)(key.dsize + old_dlen
+ + dbuf.dsize));
+ goto out;
+ }
+ ecode = tdb->methods->tread(tdb, off + sizeof(rec) + key.dsize,
+ newdata, old_dlen);
+ if (ecode != TDB_SUCCESS) {
+ goto out_free_newdata;
+ }
+ memcpy(newdata + old_dlen, dbuf.dptr, dbuf.dsize);
+ new_dbuf.dptr = newdata;
+ new_dbuf.dsize = old_dlen + dbuf.dsize;
+ } else {
+ newdata = NULL;
+ new_dbuf = dbuf;
+ }
+
+ /* If they're using tdb_append(), it implies they're growing record. */
+ ecode = replace_data(tdb, &h, key, new_dbuf, off, old_room, true);
+
+out_free_newdata:
+ free(newdata);
+out:
+ tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
+ return tdb->last_error = ecode;
+}
+
+enum TDB_ERROR tdb_fetch(struct tdb_context *tdb, struct tdb_data key,
+ struct tdb_data *data)
+{
+ tdb_off_t off;
+ struct tdb_used_record rec;
+ struct hash_info h;
+ enum TDB_ERROR ecode;
+
+ off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+ if (TDB_OFF_IS_ERR(off)) {
+ return tdb->last_error = off;
+ }
+
+ if (!off) {
+ ecode = TDB_ERR_NOEXIST;
+ } else {
+ data->dsize = rec_data_length(&rec);
+ data->dptr = tdb_alloc_read(tdb, off + sizeof(rec) + key.dsize,
+ data->dsize);
+ if (TDB_PTR_IS_ERR(data->dptr)) {
+ ecode = TDB_PTR_ERR(data->dptr);
+ } else
+ ecode = TDB_SUCCESS;
+ }
+
+ tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+ return tdb->last_error = ecode;
+}
+
+bool tdb_exists(struct tdb_context *tdb, TDB_DATA key)
+{
+ tdb_off_t off;
+ struct tdb_used_record rec;
+ struct hash_info h;
+
+ off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+ if (TDB_OFF_IS_ERR(off)) {
+ tdb->last_error = off;
+ return false;
+ }
+ tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+
+ tdb->last_error = TDB_SUCCESS;
+ return off ? true : false;
+}
+
+enum TDB_ERROR tdb_delete(struct tdb_context *tdb, struct tdb_data key)
+{
+ tdb_off_t off;
+ struct tdb_used_record rec;
+ struct hash_info h;
+ enum TDB_ERROR ecode;
+
+ off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
+ if (TDB_OFF_IS_ERR(off)) {
+ return tdb->last_error = off;
+ }
+
+ if (!off) {
+ ecode = TDB_ERR_NOEXIST;
+ goto unlock;
+ }
+
+ ecode = delete_from_hash(tdb, &h);
+ if (ecode != TDB_SUCCESS) {
+ goto unlock;
+ }
+
+ /* Free the deleted entry. */
+ tdb->stats.frees++;
+ ecode = add_free_record(tdb, off,
+ sizeof(struct tdb_used_record)
+ + rec_key_length(&rec)
+ + rec_data_length(&rec)
+ + rec_extra_padding(&rec),
+ TDB_LOCK_WAIT, true);
+
+ if (tdb->flags & TDB_SEQNUM)
+ tdb_inc_seqnum(tdb);
+
+unlock:
+ tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
+ return tdb->last_error = ecode;
+}
+
+unsigned int tdb_get_flags(struct tdb_context *tdb)
+{
+ return tdb->flags;
+}
+
+void tdb_add_flag(struct tdb_context *tdb, unsigned flag)
+{
+ if (tdb->flags & TDB_INTERNAL) {
+ tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+ TDB_LOG_USE_ERROR,
+ "tdb_add_flag: internal db");
+ return;
+ }
+ switch (flag) {
+ case TDB_NOLOCK:
+ tdb->flags |= TDB_NOLOCK;
+ break;
+ case TDB_NOMMAP:
+ tdb->flags |= TDB_NOMMAP;
+ tdb_munmap(tdb->file);
+ break;
+ case TDB_NOSYNC:
+ tdb->flags |= TDB_NOSYNC;
+ break;
+ case TDB_SEQNUM:
+ tdb->flags |= TDB_SEQNUM;
+ break;
+ case TDB_ALLOW_NESTING:
+ tdb->flags |= TDB_ALLOW_NESTING;
+ break;
+ default:
+ tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+ TDB_LOG_USE_ERROR,
+ "tdb_add_flag: Unknown flag %u",
+ flag);
+ }
+}
+
+void tdb_remove_flag(struct tdb_context *tdb, unsigned flag)
+{
+ if (tdb->flags & TDB_INTERNAL) {
+ tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+ TDB_LOG_USE_ERROR,
+ "tdb_remove_flag: internal db");
+ return;
+ }
+ switch (flag) {
+ case TDB_NOLOCK:
+ tdb->flags &= ~TDB_NOLOCK;
+ break;
+ case TDB_NOMMAP:
+ tdb->flags &= ~TDB_NOMMAP;
+ tdb_mmap(tdb);
+ break;
+ case TDB_NOSYNC:
+ tdb->flags &= ~TDB_NOSYNC;
+ break;
+ case TDB_SEQNUM:
+ tdb->flags &= ~TDB_SEQNUM;
+ break;
+ case TDB_ALLOW_NESTING:
+ tdb->flags &= ~TDB_ALLOW_NESTING;
+ break;
+ default:
+ tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+ TDB_LOG_USE_ERROR,
+ "tdb_remove_flag: Unknown flag %u",
+ flag);
+ }
+}
+
+const char *tdb_errorstr(enum TDB_ERROR ecode)
+{
+ /* Gcc warns if you miss a case in the switch, so use that. */
+ switch (ecode) {
+ case TDB_SUCCESS: return "Success";
+ case TDB_ERR_CORRUPT: return "Corrupt database";
+ case TDB_ERR_IO: return "IO Error";
+ case TDB_ERR_LOCK: return "Locking error";
+ case TDB_ERR_OOM: return "Out of memory";
+ case TDB_ERR_EXISTS: return "Record exists";
+ case TDB_ERR_EINVAL: return "Invalid parameter";
+ case TDB_ERR_NOEXIST: return "Record does not exist";
+ case TDB_ERR_RDONLY: return "write not permitted";
+ }
+ return "Invalid error code";
+}
+
+enum TDB_ERROR tdb_error(struct tdb_context *tdb)
+{
+ return tdb->last_error;
+}
+
+enum TDB_ERROR COLD tdb_logerr(struct tdb_context *tdb,
+ enum TDB_ERROR ecode,
+ enum tdb_log_level level,
+ const char *fmt, ...)
+{
+ char *message;
+ va_list ap;
+ size_t len;
+ /* tdb_open paths care about errno, so save it. */
+ int saved_errno = errno;
+
+ if (!tdb->log_fn)
+ return ecode;
+
+ va_start(ap, fmt);
+ len = vasprintf(&message, fmt, ap);
+ va_end(ap);
+
+ if (len < 0) {
+ tdb->log_fn(tdb, TDB_LOG_ERROR,
+ "out of memory formatting message:", tdb->log_data);
+ tdb->log_fn(tdb, level, fmt, tdb->log_data);
+ } else {
+ tdb->log_fn(tdb, level, message, tdb->log_data);
+ free(message);
+ }
+ errno = saved_errno;
+ return ecode;
+}
+
+enum TDB_ERROR tdb_parse_record_(struct tdb_context *tdb,
+ TDB_DATA key,
+ enum TDB_ERROR (*parse)(TDB_DATA k,
+ TDB_DATA d,
+ void *data),
+ void *data)
+{
+ tdb_off_t off;
+ struct tdb_used_record rec;
+ struct hash_info h;
+ enum TDB_ERROR ecode;
+
+ off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+ if (TDB_OFF_IS_ERR(off)) {
+ return tdb->last_error = off;
+ }
+
+ if (!off) {
+ ecode = TDB_ERR_NOEXIST;
+ } else {
+ const void *dptr;
+ dptr = tdb_access_read(tdb, off + sizeof(rec) + key.dsize,
+ rec_data_length(&rec), false);
+ if (TDB_PTR_IS_ERR(dptr)) {
+ ecode = TDB_PTR_ERR(dptr);
+ } else {
+ TDB_DATA d = tdb_mkdata(dptr, rec_data_length(&rec));
+
+ ecode = parse(key, d, data);
+ tdb_access_release(tdb, dptr);
+ }
+ }
+
+ tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+ return tdb->last_error = ecode;
+}
+
+const char *tdb_name(const struct tdb_context *tdb)
+{
+ return tdb->name;
+}
+
+int64_t tdb_get_seqnum(struct tdb_context *tdb)
+{
+ tdb_off_t off = tdb_read_off(tdb, offsetof(struct tdb_header, seqnum));
+ if (TDB_OFF_IS_ERR(off))
+ tdb->last_error = off;
+ else
+ tdb->last_error = TDB_SUCCESS;
+ return off;
+}
+
+
+int tdb_fd(const struct tdb_context *tdb)
+{
+ return tdb->file->fd;
+}