Fix two small bugs in json's populate_record_worker

The first bug is not releasing a tupdesc when doing an early return out
of the function. The second bug is a logic error in choosing when to do
an early return if given an empty jsonb object.

Bug reports from Pavel Stehule and Tom Lane respectively.

Backpatch to 9.4 where these were introduced.

diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index 274f64c95f81c1d320f372aa62d6d0acc776428b..5f61cfcb73ae7f1510f489e91868b192f1336398 100644 (file)
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -2115,6 +2115,7 @@ populate_record_worker(FunctionCallInfo fcinfo, const char *funcname,
        if (hash_get_num_entries(json_hash) == 0 && rec)
        {
            hash_destroy(json_hash);
+           ReleaseTupleDesc(tupdesc);
            PG_RETURN_POINTER(rec);
        }
    }
@@ -2123,8 +2124,11 @@ populate_record_worker(FunctionCallInfo fcinfo, const char *funcname,
        jb = PG_GETARG_JSONB(json_arg_num);
 
        /* same logic as for json */
-       if (!have_record_arg && rec)
+       if (JB_ROOT_COUNT(jb) == 0 && rec)
+       {
+           ReleaseTupleDesc(tupdesc);
            PG_RETURN_POINTER(rec);
+       }
    }
 
    ncolumns = tupdesc->natts;