+
+static tdb_len_t adjust_size(size_t keylen, size_t datalen, bool growing)
+{
+ tdb_len_t size = keylen + datalen;
+
+ if (size < MIN_DATA_LEN)
+ size = MIN_DATA_LEN;
+
+ /* Overallocate if this is coming from an enlarging store. */
+ if (growing)
+ size += datalen / 2;
+
+ /* Round to next uint64_t boundary. */
+ return (size + (sizeof(uint64_t) - 1ULL)) & ~(sizeof(uint64_t) - 1ULL);
+}
+
+/* This won't fail: it will expand the database if it has to. */
+tdb_off_t alloc(struct tdb_context *tdb, size_t keylen, size_t datalen,
+ uint64_t hash, bool growing)
+{
+ tdb_off_t off;
+ tdb_len_t size, actual;
+ struct tdb_used_record rec;
+
+ /* We don't want header to change during this! */
+ assert(tdb->header_uptodate);
+
+ size = adjust_size(keylen, datalen, growing);
+
+again:
+ off = get_free(tdb, size, &actual);
+ if (unlikely(off == TDB_OFF_ERR))
+ return off;
+
+ if (unlikely(off == 0)) {
+ if (tdb_expand(tdb, size) == -1)
+ return TDB_OFF_ERR;
+ goto again;
+ }
+
+ /* Some supergiant values can't be encoded. */
+ /* FIXME: Check before, and limit actual in get_free. */
+ if (set_header(tdb, &rec, keylen, datalen, actual, hash,
+ tdb->zhdr.zone_bits) != 0) {
+ add_free_record(tdb, tdb->zhdr.zone_bits, off,
+ sizeof(rec) + actual);
+ return TDB_OFF_ERR;
+ }
+
+ if (tdb_write_convert(tdb, off, &rec, sizeof(rec)) != 0)
+ return TDB_OFF_ERR;
+
+ return off;
+}