+static int mdb_midl_grow( MDB_IDL *idp, int num )
+{
+ MDB_IDL idn = *idp-1;
+ /* grow it */
+ idn = realloc(idn, (*idn + num + 2) * sizeof(MDB_ID));
+ if (!idn)
+ return ENOMEM;
+ *idn++ += num;
+ *idp = idn;
+ return 0;
+}
+
+int mdb_midl_need( MDB_IDL *idp, unsigned num )
+{
+ MDB_IDL ids = *idp;
+ num += ids[0];
+ if (num > ids[-1]) {
+ num = (num + num/4 + (256 + 2)) & -256;
+ if (!(ids = realloc(ids-1, num * sizeof(MDB_ID))))
+ return ENOMEM;
+ *ids++ = num -= 2;
+ *idp = ids;
+ }
+ return 0;
+}
+