OClCollMeshEngn: fix mem leak in [un]mapBuffer()

stimBuffApis/livoxGen1/openClCollatingAndMeshingEngine.cpp

@@ -747,20 +747,22 @@ bool OpenClCollatingAndMeshingEngine::mapBuffer(
 	if (mappedPtr != nullptr) { return true; }
 
 	cl_int err;
-	cl_event mapEvent;
 	mappedPtr = clEnqueueMapBuffer(
 		commandQueue, buffer, CL_TRUE, mapFlags,
-		0, size, 0, nullptr, &mapEvent, &err);
+		0, size, 0, nullptr, nullptr, &err);
 
 	if (err != CL_SUCCESS || !mappedPtr)
 	{
 		std::cerr << __func__ << ": failed to map buffer: " << err
 			<< std::endl;
-		mappedPtr = nullptr;
-		return false;
+		goto cleanup;
 	}
 
 	return true;
+
+cleanup:
+	mappedPtr = nullptr;
+	return false;
 }
 
 bool OpenClCollatingAndMeshingEngine::unmapBuffer(cl_mem buffer, void*& mappedPtr)
@@ -778,7 +780,7 @@ bool OpenClCollatingAndMeshingEngine::unmapBuffer(cl_mem buffer, void*& mappedPt
 	}
 
 	cl_int err;
-	cl_event unmapEvent;
+	cl_event unmapEvent = nullptr;
 	err = clEnqueueUnmapMemObject(
 		commandQueue, buffer, mappedPtr,
 		0, nullptr, &unmapEvent);
@@ -787,11 +789,26 @@ bool OpenClCollatingAndMeshingEngine::unmapBuffer(cl_mem buffer, void*& mappedPt
 	{
 		std::cerr << __func__ << ": failed to unmap buffer: " << err
 			<< std::endl;
-		return false;
+		goto cleanup;
 	}
 
+	// Wait for unmap to complete and release the event
+	err = clWaitForEvents(1, &unmapEvent);
+	if (err != CL_SUCCESS)
+	{
+		std::cerr << __func__ << ": failed to wait for unmap event: " << err
+			<< std::endl;
+		goto cleanup_unmapEvent;
+	}
+
+	clReleaseEvent(unmapEvent);
 	mappedPtr = nullptr;
 	return true;
+
+cleanup_unmapEvent:
+	clReleaseEvent(unmapEvent);
+cleanup:
+	return false;
 }
 
 bool OpenClCollatingAndMeshingEngine::mapAssemblyBuffer(cl_map_flags mapFlags)