fix(websocket): Treat write timeouts as partial success (not fatal errors)

Author: david-cermak

components/esp_websocket_client/esp_websocket_client.c

@@ -243,6 +243,13 @@ static esp_err_t esp_websocket_client_dispatch_event(esp_websocket_client_handle
 static esp_err_t esp_websocket_client_abort_connection(esp_websocket_client_handle_t client, esp_websocket_error_type_t error_type)
 {
     ESP_WS_CLIENT_STATE_CHECK(TAG, client, return ESP_FAIL);
+
+    // Prevent double connection close - check if already closing or closed
+    if (client->state == WEBSOCKET_STATE_CLOSING || client->state == WEBSOCKET_STATE_UNKNOW) {
+        ESP_LOGV(TAG, "Connection already closing/closed, skipping abort");
+        return ESP_OK;
+    }
+
     esp_transport_close(client->transport);
 
     if (!client->config->auto_reconnect) {
@@ -654,19 +661,58 @@ static int esp_websocket_client_send_with_exact_opcode(esp_websocket_client_hand
         // send with ws specific way and specific opcode
         wlen = esp_transport_ws_send_raw(client->transport, opcode, (char *)client->tx_buffer, need_write,
                                          (timeout == portMAX_DELAY) ? -1 : timeout * portTICK_PERIOD_MS);
-        if (wlen < 0 || (wlen == 0 && need_write != 0)) {
+        if (wlen < 0) {
+            // Handle negative return values (actual errors)
             ret = wlen;
             esp_websocket_free_buf(client, true);
             esp_tls_error_handle_t error_handle = esp_transport_get_error_handle(client->transport);
             if (error_handle) {
-                esp_websocket_client_error(client, "esp_transport_write() returned %d, transport_error=%s, tls_error_code=%i, tls_flags=%i, errno=%d",
-                                           ret, esp_err_to_name(error_handle->last_error), error_handle->esp_tls_error_code,
-                                           error_handle->esp_tls_flags, errno);
+                // Check for specific transport error codes
+                if (error_handle->last_error == ESP_ERR_ESP_TLS_CONNECTION_TIMEOUT) {
+                    ESP_LOGV(TAG, "Transport layer reported timeout during write");
+                    // Treat timeout as partial success, don't abort connection
+                    ret = 0; // Return 0 to indicate no bytes written but not an error
+                } else if (error_handle->last_error == ESP_ERR_ESP_TLS_TCP_CLOSED_FIN) {
+                    ESP_LOGD(TAG, "Connection closed by peer during write (FIN)");
+                    esp_websocket_client_abort_connection(client, WEBSOCKET_ERROR_TYPE_TCP_TRANSPORT);
+                } else {
+                    esp_websocket_client_error(client, "esp_transport_write() failed with %d, transport_error=%s, tls_error_code=%i, tls_flags=%i, errno=%d",
+                                               ret, esp_err_to_name(error_handle->last_error), error_handle->esp_tls_error_code,
+                                               error_handle->esp_tls_flags, errno);
+                    esp_websocket_client_abort_connection(client, WEBSOCKET_ERROR_TYPE_TCP_TRANSPORT);
+                }
             } else {
-                esp_websocket_client_error(client, "esp_transport_write() returned %d, errno=%d", ret, errno);
+                esp_websocket_client_error(client, "esp_transport_write() failed with %d, errno=%d", ret, errno);
+                esp_websocket_client_abort_connection(client, WEBSOCKET_ERROR_TYPE_TCP_TRANSPORT);
             }
-            esp_websocket_client_abort_connection(client, WEBSOCKET_ERROR_TYPE_TCP_TRANSPORT);
             goto unlock_and_return;
+        } else if (wlen == 0 && need_write != 0) {
+            // Handle zero return value - could be timeout or connection issue
+            esp_tls_error_handle_t error_handle = esp_transport_get_error_handle(client->transport);
+            bool is_timeout = false;
+
+            if (error_handle) {
+                // Check for specific transport error codes that indicate timeout
+                if (error_handle->last_error == ESP_ERR_ESP_TLS_CONNECTION_TIMEOUT) {
+                    is_timeout = true;
+                    ESP_LOGV(TAG, "Transport layer reported timeout during write (wlen=0)");
+                }
+            }
+
+            if (is_timeout) {
+                // Timeout during write - treat as partial success, don't abort connection
+                ESP_LOGV(TAG, "Write timeout detected, treating as partial success");
+                ret = 0; // Return 0 to indicate no bytes written but not an error
+                esp_websocket_free_buf(client, true);
+                goto unlock_and_return;
+            } else {
+                // Not a timeout - likely connection issue, abort connection
+                ret = -1;
+                esp_websocket_free_buf(client, true);
+                esp_websocket_client_error(client, "esp_transport_write() returned 0 with no timeout, connection may be broken");
+                esp_websocket_client_abort_connection(client, WEBSOCKET_ERROR_TYPE_TCP_TRANSPORT);
+                goto unlock_and_return;
+            }
         }
         opcode = 0;
         widx += wlen;