fix(client): fix potential memory leak.

source/client/src/clientTmq.c

@@ -874,7 +874,7 @@ int32_t tmqHandleAllDelayedTask(tmq_t* pTmq) {
   return 0;
 }
 
-static void tmqFreeRspWrapper(SMqRspWrapper* rspWrapper) {
+static void* tmqFreeRspWrapper(SMqRspWrapper* rspWrapper) {
   if (rspWrapper->tmqRspType == TMQ_MSG_TYPE__END_RSP) {
     // do nothing
   } else if (rspWrapper->tmqRspType == TMQ_MSG_TYPE__EP_RSP) {
@@ -905,6 +905,8 @@ static void tmqFreeRspWrapper(SMqRspWrapper* rspWrapper) {
     taosArrayDestroy(pRsp->taosxRsp.createTableLen);
     taosArrayDestroyP(pRsp->taosxRsp.createTableReq, taosMemoryFree);
   }
+
+  return NULL;
 }
 
 void tmqClearUnhandleMsg(tmq_t* tmq) {
@@ -1788,29 +1790,28 @@ static void* tmqHandleAllRsp(tmq_t* tmq, int64_t timeout, bool pollIfReset) {
   tscDebug("consumer:0x%" PRIx64 " start to handle the rsp, total:%d", tmq->consumerId, tmq->qall->numOfItems);
 
   while (1) {
-    SMqRspWrapper* rspWrapper = NULL;
-    taosGetQitem(tmq->qall, (void**)&rspWrapper);
+    SMqRspWrapper* pRspWrapper = NULL;
+    taosGetQitem(tmq->qall, (void**)&pRspWrapper);
 
-    if (rspWrapper == NULL) {
+    if (pRspWrapper == NULL) {
       taosReadAllQitems(tmq->mqueue, tmq->qall);
-      taosGetQitem(tmq->qall, (void**)&rspWrapper);
+      taosGetQitem(tmq->qall, (void**)&pRspWrapper);
 
-      if (rspWrapper == NULL) {
+      if (pRspWrapper == NULL) {
         return NULL;
       }
     }
 
-    tscDebug("consumer:0x%"PRIx64" handle rsp, type:%d", tmq->consumerId, rspWrapper->tmqRspType);
+    tscDebug("consumer:0x%"PRIx64" handle rsp, type:%d", tmq->consumerId, pRspWrapper->tmqRspType);
 
-    if (rspWrapper->tmqRspType == TMQ_MSG_TYPE__END_RSP) {
-      taosFreeQitem(rspWrapper);
+    if (pRspWrapper->tmqRspType == TMQ_MSG_TYPE__END_RSP) {
+      taosFreeQitem(pRspWrapper);
       terrno = TSDB_CODE_TQ_NO_COMMITTED_OFFSET;
       tscError("consumer:0x%" PRIx64 " unexpected rsp from poll, code:%s", tmq->consumerId, tstrerror(terrno));
       return NULL;
-    } else if (rspWrapper->tmqRspType == TMQ_MSG_TYPE__POLL_RSP) {
-      SMqPollRspWrapper* pollRspWrapper = (SMqPollRspWrapper*)rspWrapper;
+    } else if (pRspWrapper->tmqRspType == TMQ_MSG_TYPE__POLL_RSP) {
+      SMqPollRspWrapper* pollRspWrapper = (SMqPollRspWrapper*)pRspWrapper;
 
-      /*atomic_sub_fetch_32(&tmq->readyRequest, 1);*/
       int32_t consumerEpoch = atomic_load_32(&tmq->epoch);
       SMqDataRsp* pDataRsp = &pollRspWrapper->dataRsp;
 
@@ -1835,9 +1836,8 @@ static void* tmqHandleAllRsp(tmq_t* tmq, int64_t timeout, bool pollIfReset) {
         if (pDataRsp->blockNum == 0) {
           tscDebug("consumer:0x%" PRIx64 " empty block received, vgId:%d, offset:%s, reqId:0x%" PRIx64, tmq->consumerId,
                    pVg->vgId, buf, pollRspWrapper->reqId);
+          pRspWrapper = tmqFreeRspWrapper(pRspWrapper);
           taosFreeQitem(pollRspWrapper);
-          rspWrapper = NULL;
-          continue;
         } else {  // build rsp
           SMqRspObj* pRsp = tmqBuildRspFromWrapper(pollRspWrapper, pVg);
           tscDebug("consumer:0x%" PRIx64 " process poll rsp, vgId:%d, offset:%s, blocks:%d, rows:%"PRId64" reqId:0x%" PRIx64,
@@ -1850,11 +1850,11 @@ static void* tmqHandleAllRsp(tmq_t* tmq, int64_t timeout, bool pollIfReset) {
       } else {
         tscDebug("consumer:0x%" PRIx64 " msg discard since epoch mismatch: msg epoch %d, consumer epoch %d",
                  tmq->consumerId, pDataRsp->head.epoch, consumerEpoch);
-        tmqFreeRspWrapper(rspWrapper);
+        pRspWrapper = tmqFreeRspWrapper(pRspWrapper);
         taosFreeQitem(pollRspWrapper);
       }
-    } else if (rspWrapper->tmqRspType == TMQ_MSG_TYPE__POLL_META_RSP) {
-      SMqPollRspWrapper* pollRspWrapper = (SMqPollRspWrapper*)rspWrapper;
+    } else if (pRspWrapper->tmqRspType == TMQ_MSG_TYPE__POLL_META_RSP) {
+      SMqPollRspWrapper* pollRspWrapper = (SMqPollRspWrapper*)pRspWrapper;
       int32_t            consumerEpoch = atomic_load_32(&tmq->epoch);
 
       tscDebug("consumer:0x%" PRIx64 " process meta rsp", tmq->consumerId);
@@ -1870,11 +1870,11 @@ static void* tmqHandleAllRsp(tmq_t* tmq, int64_t timeout, bool pollIfReset) {
       } else {
         tscDebug("consumer:0x%" PRIx64 " msg discard since epoch mismatch: msg epoch %d, consumer epoch %d",
                  tmq->consumerId, pollRspWrapper->metaRsp.head.epoch, consumerEpoch);
-        tmqFreeRspWrapper(rspWrapper);
+        pRspWrapper = tmqFreeRspWrapper(pRspWrapper);
         taosFreeQitem(pollRspWrapper);
       }
-    } else if (rspWrapper->tmqRspType == TMQ_MSG_TYPE__TAOSX_RSP) {
-      SMqPollRspWrapper* pollRspWrapper = (SMqPollRspWrapper*)rspWrapper;
+    } else if (pRspWrapper->tmqRspType == TMQ_MSG_TYPE__TAOSX_RSP) {
+      SMqPollRspWrapper* pollRspWrapper = (SMqPollRspWrapper*)pRspWrapper;
       int32_t consumerEpoch = atomic_load_32(&tmq->epoch);
 
       if (pollRspWrapper->taosxRsp.head.epoch == consumerEpoch) {
@@ -1883,10 +1883,10 @@ static void* tmqHandleAllRsp(tmq_t* tmq, int64_t timeout, bool pollIfReset) {
         atomic_store_32(&pVg->vgStatus, TMQ_VG_STATUS__IDLE);
 
         if (pollRspWrapper->taosxRsp.blockNum == 0) {
-          rspWrapper = NULL;
           tscDebug("consumer:0x%" PRIx64 " taosx empty block received, vgId:%d, reqId:0x%" PRIx64, tmq->consumerId, pVg->vgId,
                    pollRspWrapper->reqId);
           pVg->emptyBlockReceiveTs = taosGetTimestampMs();
+          pRspWrapper = tmqFreeRspWrapper(pRspWrapper);
           taosFreeQitem(pollRspWrapper);
           continue;
         } else {
@@ -1912,15 +1912,15 @@ static void* tmqHandleAllRsp(tmq_t* tmq, int64_t timeout, bool pollIfReset) {
       } else {
         tscDebug("consumer:0x%" PRIx64 " msg discard since epoch mismatch: msg epoch %d, consumer epoch %d",
                  tmq->consumerId, pollRspWrapper->taosxRsp.head.epoch, consumerEpoch);
-        tmqFreeRspWrapper(rspWrapper);
+        pRspWrapper = tmqFreeRspWrapper(pRspWrapper);
         taosFreeQitem(pollRspWrapper);
       }
     } else {
       tscDebug("consumer:0x%" PRIx64 " not data msg received", tmq->consumerId);
 
       bool reset = false;
-      tmqHandleNoPollRsp(tmq, rspWrapper, &reset);
-      taosFreeQitem(rspWrapper);
+      tmqHandleNoPollRsp(tmq, pRspWrapper, &reset);
+      taosFreeQitem(pRspWrapper);
       if (pollIfReset && reset) {
         tscDebug("consumer:0x%" PRIx64 ", reset and repoll", tmq->consumerId);
         tmqPollImpl(tmq, timeout);
@@ -1968,7 +1968,6 @@ TAOS_RES* tmq_consumer_poll(tmq_t* tmq, int64_t timeout) {
 
     if (tmqPollImpl(tmq, timeout) < 0) {
       tscDebug("consumer:0x%" PRIx64 " return due to poll error", tmq->consumerId);
-      /*return NULL;*/
     }
 
     rspObj = tmqHandleAllRsp(tmq, timeout, false);