Fix queryables memory leak (#880)

* fix: null malloc allocation

* fix: memory leak in queryables

* fix: avoid api call null size alloc

* fix: cmake unstable warning

* build: bad compile config in workflow

* fix: revert matching changes

src/api/api.c

@@ -261,6 +261,9 @@ z_result_t z_bytes_to_string(const z_loaned_bytes_t *bytes, z_owned_string_t *s)
     z_internal_string_null(s);
     // Convert bytes to string
     size_t len = _z_bytes_len(bytes);
+    if (len == 0) {
+        return _Z_RES_OK;
+    }
     s->_val = _z_string_preallocate(len);
     if (_z_string_len(&s->_val) != len) return _Z_ERR_SYSTEM_OUT_OF_MEMORY;
     _z_bytes_to_buf(bytes, (uint8_t *)_z_string_data(&s->_val), len);

src/session/queryable.c

@@ -215,6 +215,9 @@ static z_result_t _z_trigger_queryables_inner(_z_session_rc_t *zsrc, _z_msg_quer
              (int)_z_string_len(&qle_infos.ke_out._suffix), _z_string_data(&qle_infos.ke_out._suffix));
     if (qle_infos.qle_nb == 0) {
         _z_keyexpr_clear(&qle_infos.ke_out);
+#if Z_FEATURE_RX_CACHE == 0
+        _z_queryable_infos_svec_release(&qle_infos.infos);  // Otherwise it's released with cache
+#endif
         return _Z_RES_OK;
     }
     // Check anyke
@@ -243,7 +246,7 @@ static z_result_t _z_trigger_queryables_inner(_z_session_rc_t *zsrc, _z_msg_quer
     _z_query_rc_drop(&query);
     // Clean up
     _z_keyexpr_clear(&qle_infos.ke_out);
-#if Z_FEATURE_RX_CACHE != 1
+#if Z_FEATURE_RX_CACHE == 0
     _z_queryable_infos_svec_release(&qle_infos.infos);  // Otherwise it's released with cache
 #endif
     return _Z_RES_OK;