Close #107 不能正确处理502 Bad Gateway的问题

* 修正为当HTTP请求未完成时，认为整个HTTP Session非法，不处理。

plugin/protocol/http/src/http_entry.cpp

@@ -223,7 +223,7 @@ static int __on_request_handle_user_req_or_resp(const tfe_stream * stream, struc
 		ret = __write_http_half_to_line(stream, CONN_DIR_UPSTREAM, hf_private_req_user);
 		if (unlikely(ret < 0))
 		{
-			TFE_STREAM_LOG_ERROR(stream, "Failed to write HTTP request setup by user. ");
+			TFE_LOG_ERROR(g_http_plugin->logger, "Failed to write HTTP request setup by user. ");
 			return ret;
 		}
 
@@ -246,7 +246,7 @@ static int __on_request_handle_user_req_or_resp(const tfe_stream * stream, struc
 
 		if (unlikely(ret < 0))
 		{
-			TFE_STREAM_LOG_ERROR(stream, "Failed to write HTTP request setup by user.");
+            TFE_LOG_ERROR(g_http_plugin->logger, "Failed to write HTTP request setup by user.");
 			goto __errout;
 		}
 
@@ -271,7 +271,7 @@ static int __on_response_handle_user_req_or_resp(const tfe_stream * stream, stru
 	int ret = __write_http_half_to_line(stream, CONN_DIR_DOWNSTREAM, hf_private_resp_user);
 	if (unlikely(ret < 0))
 	{
-		TFE_STREAM_LOG_ERROR(stream, "Failed to write HTTP response setup by user.");
+        TFE_LOG_ERROR(g_http_plugin->logger, "Failed to write HTTP response setup by user.");
 		return -1;
 	}
 
@@ -328,7 +328,17 @@ static int __on_response_prepare_context(const struct tfe_stream * stream, unsig
 	/* Standalone response, it means missing something or malformed http protocol */
 	if (hs_private == NULL)
 	{
-		TFE_STREAM_LOG_ERROR(stream, "Standlone HTTP response emerged. Malformed HTTP Protocol, detached. ");
+        TFE_LOG_ERROR(g_http_plugin->logger, "Standlone HTTP response emerged. Malformed HTTP Protocol, detached. ");
+		return -1;
+	}
+
+	struct http_half_private * hf_private_req_in = to_hf_request_private(hs_private);
+
+	/* The request is not completed, but response arrival.
+	 * Something wrong happends to server, like 502 bad gateway */
+	if(hf_private_req_in->message_status != STATUS_COMPLETE)
+	{
+		TFE_LOG_ERROR(g_http_plugin->logger, "Response arrival when request is not completed, detached. ");
 		return -1;
 	}