From db121a56e13b4b93b6bcc9217f7890bc4783cabd Mon Sep 17 00:00:00 2001
From: David Cermak <cermak@espressif.com>
Date: Tue, 30 Apr 2019 11:41:39 +0200
Subject: [PATCH] tcp_transport: modified ws_read to read payload directly to
 the read buffer and separately from header bytes

Previous version read all data to the buffer including header which reduced maximum payload read. This version uses a local array to receive header and reads payload bytes to the buffer
---
 components/mqtt/esp-mqtt                |  2 +-
 components/tcp_transport/transport_ws.c | 24 +++++++++---------------
 2 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/components/mqtt/esp-mqtt b/components/mqtt/esp-mqtt
index 39118d5182..18b6f2c582 160000
--- a/components/mqtt/esp-mqtt
+++ b/components/mqtt/esp-mqtt
@@ -1 +1 @@
-Subproject commit 39118d5182f804edc01ed030c8ba137a9c7f388e
+Subproject commit 18b6f2c58231728805ff813d46021d07ed023dcb
diff --git a/components/tcp_transport/transport_ws.c b/components/tcp_transport/transport_ws.c
index a760ecfec0..e31149e178 100644
--- a/components/tcp_transport/transport_ws.c
+++ b/components/tcp_transport/transport_ws.c
@@ -192,8 +192,8 @@ static int ws_read(esp_transport_handle_t t, char *buffer, int len, int timeout_
 {
     transport_ws_t *ws = esp_transport_get_context_data(t);
     int payload_len;
-    int payload_len_buff = len;
-    char *data_ptr = buffer, opcode, mask, *mask_key = NULL;
+    char ws_header[MAX_WEBSOCKET_HEADER_SIZE];
+    char *data_ptr = ws_header, opcode, mask, *mask_key = NULL;
     int rlen;
     int poll_read;
     if ((poll_read = esp_transport_poll_read(ws->parent, timeout_ms)) <= 0) {
@@ -202,7 +202,7 @@ static int ws_read(esp_transport_handle_t t, char *buffer, int len, int timeout_
 
     // Receive and process header first (based on header size)
     int header = 2;
-    if ((rlen = esp_transport_read(ws->parent, buffer, header, timeout_ms)) <= 0) {
+    if ((rlen = esp_transport_read(ws->parent, data_ptr, header, timeout_ms)) <= 0) {
         ESP_LOGE(TAG, "Error read data");
         return rlen;
     }
@@ -219,8 +219,6 @@ static int ws_read(esp_transport_handle_t t, char *buffer, int len, int timeout_
             return rlen;
         }
         payload_len = data_ptr[0] << 8 | data_ptr[1];
-        payload_len_buff = len - 4;
-        data_ptr += 2;
     } else if (payload_len == 127) {
         // headerLen += 8;
         header = 8;
@@ -235,29 +233,25 @@ static int ws_read(esp_transport_handle_t t, char *buffer, int len, int timeout_
         } else {
             payload_len = data_ptr[4] << 24 | data_ptr[5] << 16 | data_ptr[6] << 8 | data_ptr[7];
         }
-        data_ptr += 8;
-        payload_len_buff = len - 10;
     }
 
-    if (payload_len > payload_len_buff) {
-        ESP_LOGD(TAG, "Actual data to receive (%d) are longer than ws buffer (%d)", payload_len, payload_len_buff);
-        payload_len = payload_len_buff;
+    if (payload_len > len) {
+        ESP_LOGD(TAG, "Actual data to receive (%d) are longer than ws buffer (%d)", payload_len, len);
+        payload_len = len;
     }
 
     // Then receive and process payload
-    if ((rlen = esp_transport_read(ws->parent, data_ptr, payload_len, timeout_ms)) <= 0) {
+    if ((rlen = esp_transport_read(ws->parent, buffer, payload_len, timeout_ms)) <= 0) {
         ESP_LOGE(TAG, "Error read data");
         return rlen;
     }
 
     if (mask) {
-        mask_key = data_ptr;
-        data_ptr += 4;
+        mask_key = buffer;
+        data_ptr = buffer + 4;
         for (int i = 0; i < payload_len; i++) {
             buffer[i] = (data_ptr[i] ^ mask_key[i % 4]);
         }
-    } else {
-        memmove(buffer, data_ptr, payload_len);
     }
     return payload_len;
 }