return TDB_OFF_ERR;
}
+/* Returns -1 on error, 0 on OK, 1 on "expand and retry." */
+static int replace_data(struct tdb_context *tdb,
+ uint64_t h, struct tdb_data key, struct tdb_data dbuf,
+ tdb_off_t bucket,
+ tdb_off_t old_off, tdb_len_t old_room,
+ bool growing)
+{
+ tdb_off_t new_off;
+
+ /* Allocate a new record. */
+ new_off = alloc(tdb, key.dsize, dbuf.dsize, h, growing);
+ if (new_off == 0)
+ return 1;
+
+ /* We didn't like the existing one: remove it. */
+ if (old_off)
+ add_free_record(tdb, old_off,
+ sizeof(struct tdb_used_record)
+ + key.dsize + old_room);
+
+ /* FIXME: Encode extra hash bits! */
+ if (tdb_write_off(tdb, hash_off(tdb, bucket), new_off) == -1)
+ return -1;
+
+ new_off += sizeof(struct tdb_used_record);
+ if (tdb->methods->write(tdb, new_off, key.dptr, key.dsize) == -1)
+ return -1;
+
+ new_off += key.dsize;
+ if (tdb->methods->write(tdb, new_off, dbuf.dptr, dbuf.dsize) == -1)
+ return -1;
+
+ /* FIXME: tdb_increment_seqnum(tdb); */
+ return 0;
+}
+
int tdb_store(struct tdb_context *tdb,
struct tdb_data key, struct tdb_data dbuf, int flag)
{
- tdb_off_t new_off, off, bucket, start, num;
+ tdb_off_t off, bucket, start, num;
+ tdb_len_t old_room = 0;
struct tdb_used_record rec;
uint64_t h;
- bool growing = false;
+ int ret;
h = tdb_hash(tdb, key.dptr, key.dsize);
off = find_and_lock(tdb, key, h, F_WRLCK, &start, &num, &bucket, &rec);
}
} else {
if (off) {
- if (rec_data_length(&rec) + rec_extra_padding(&rec)
- >= dbuf.dsize) {
- new_off = off;
+ old_room = rec_data_length(&rec)
+ + rec_extra_padding(&rec);
+ if (old_room >= dbuf.dsize) {
+ /* Can modify in-place. Easy! */
if (update_rec_hdr(tdb, off,
key.dsize, dbuf.dsize,
&rec, h))
goto fail;
- goto write;
+ if (tdb->methods->write(tdb, off + sizeof(rec)
+ + key.dsize,
+ dbuf.dptr, dbuf.dsize))
+ goto fail;
+ unlock_lists(tdb, start, num, F_WRLCK);
+ return 0;
}
/* FIXME: See if right record is free? */
- /* Hint to allocator that we've realloced. */
- growing = true;
} else {
if (flag == TDB_MODIFY) {
/* if the record doesn't exist and we
}
}
- /* Allocate a new record. */
- new_off = alloc(tdb, key.dsize, dbuf.dsize, h, growing);
- if (new_off == 0) {
- unlock_lists(tdb, start, num, F_WRLCK);
+ /* If we didn't use the old record, this implies we're growing. */
+ ret = replace_data(tdb, h, key, dbuf, bucket, off, old_room, off != 0);
+ unlock_lists(tdb, start, num, F_WRLCK);
+
+ if (unlikely(ret == 1)) {
/* Expand, then try again... */
- if (tdb_expand(tdb, key.dsize, dbuf.dsize, growing) == -1)
+ if (tdb_expand(tdb, key.dsize, dbuf.dsize, off != 0) == -1)
return -1;
return tdb_store(tdb, key, dbuf, flag);
}
- /* We didn't like the existing one: remove it. */
+ /* FIXME: by simple simulation, this approximated 60% full.
+ * Check in real case! */
+ if (unlikely(num > 4 * tdb->header.v.hash_bits - 30))
+ enlarge_hash(tdb);
+
+ return ret;
+
+fail:
+ unlock_lists(tdb, start, num, F_WRLCK);
+ return -1;
+}
+
+int tdb_append(struct tdb_context *tdb,
+ struct tdb_data key, struct tdb_data dbuf)
+{
+ tdb_off_t off, bucket, start, num;
+ struct tdb_used_record rec;
+ tdb_len_t old_room = 0, old_dlen;
+ uint64_t h;
+ unsigned char *newdata;
+ struct tdb_data new_dbuf;
+ int ret;
+
+ h = tdb_hash(tdb, key.dptr, key.dsize);
+ off = find_and_lock(tdb, key, h, F_WRLCK, &start, &num, &bucket, &rec);
+ if (unlikely(off == TDB_OFF_ERR))
+ return -1;
+
if (off) {
- add_free_record(tdb, off, sizeof(struct tdb_used_record)
- + rec_key_length(&rec)
- + rec_data_length(&rec)
- + rec_extra_padding(&rec));
- }
+ old_dlen = rec_data_length(&rec);
+ old_room = old_dlen + rec_extra_padding(&rec);
- /* FIXME: Encode extra hash bits! */
- if (tdb_write_off(tdb, hash_off(tdb, bucket), new_off) == -1)
- goto fail;
+ /* Fast path: can append in place. */
+ if (rec_extra_padding(&rec) >= dbuf.dsize) {
+ if (update_rec_hdr(tdb, off, key.dsize,
+ old_dlen + dbuf.dsize, &rec, h))
+ goto fail;
-write:
- off = new_off + sizeof(struct tdb_used_record);
- if (tdb->methods->write(tdb, off, key.dptr, key.dsize) == -1)
- goto fail;
- off += key.dsize;
- if (tdb->methods->write(tdb, off, dbuf.dptr, dbuf.dsize) == -1)
- goto fail;
+ off += sizeof(rec) + key.dsize + old_dlen;
+ if (tdb->methods->write(tdb, off, dbuf.dptr,
+ dbuf.dsize) == -1)
+ goto fail;
- /* FIXME: tdb_increment_seqnum(tdb); */
+ /* FIXME: tdb_increment_seqnum(tdb); */
+ unlock_lists(tdb, start, num, F_WRLCK);
+ return 0;
+ }
+ /* FIXME: Check right record free? */
+
+ /* Slow path. */
+ newdata = malloc(key.dsize + old_dlen + dbuf.dsize);
+ if (!newdata) {
+ tdb->ecode = TDB_ERR_OOM;
+ tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
+ "tdb_append: cannot allocate %llu bytes!\n",
+ (long long)key.dsize + old_dlen + dbuf.dsize);
+ goto fail;
+ }
+ if (tdb->methods->read(tdb, off + sizeof(rec) + key.dsize,
+ newdata, old_dlen) != 0) {
+ free(newdata);
+ goto fail;
+ }
+ 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. */
+ ret = replace_data(tdb, h, key, new_dbuf, bucket, off, old_room, true);
unlock_lists(tdb, start, num, F_WRLCK);
+ free(newdata);
+
+ if (unlikely(ret == 1)) {
+ /* Expand, then try again. */
+ if (tdb_expand(tdb, key.dsize, dbuf.dsize, true) == -1)
+ return -1;
+ return tdb_append(tdb, key, dbuf);
+ }
/* FIXME: by simple simulation, this approximated 60% full.
* Check in real case! */
projects / ccan-lca-2011.git / blobdiff