From 5d58982f77e27143b5e046dc14af7dbf8cc99048 Mon Sep 17 00:00:00 2001
From: Benjamin Sergeant <bsergeant@mz.com>
Date: Tue, 3 Sep 2019 15:48:55 -0700
Subject: [PATCH] IXWebSocketTransport message processing refactoring

---
 ixwebsocket/IXWebSocketTransport.cpp | 38 ++++++++++------------------
 ixwebsocket/IXWebSocketTransport.h   |  2 +-
 2 files changed, 14 insertions(+), 26 deletions(-)

diff --git a/ixwebsocket/IXWebSocketTransport.cpp b/ixwebsocket/IXWebSocketTransport.cpp
index 4c7cf492..6cd10758 100644
--- a/ixwebsocket/IXWebSocketTransport.cpp
+++ b/ixwebsocket/IXWebSocketTransport.cpp
@@ -558,13 +558,16 @@ namespace ix
                 return;
             }
 
+            unmaskReceiveBuffer(ws);
+            std::string frameData(_rxbuf.begin()+ws.header_size,
+                                  _rxbuf.begin()+ws.header_size+(size_t) ws.N);
+
             // We got a whole message, now do something with it:
             if (
                    ws.opcode == wsheader_type::TEXT_FRAME
                 || ws.opcode == wsheader_type::BINARY_FRAME
                 || ws.opcode == wsheader_type::CONTINUATION
             ) {
-                unmaskReceiveBuffer(ws);
 
                 if (ws.opcode != wsheader_type::CONTINUATION)
                 {
@@ -593,8 +596,7 @@ namespace ix
                 if (ws.fin && _chunks.empty())
                 {
                     emitMessage(_fragmentedMessageKind,
-                                std::string(_rxbuf.begin()+ws.header_size,
-                                            _rxbuf.begin()+ws.header_size+(size_t) ws.N),
+                                frameData,
                                 ws,
                                 onMessageCallback);
                 }
@@ -607,9 +609,8 @@ namespace ix
                     // the internal buffer which is slow and can let the internal OS
                     // receive buffer fill out.
                     //
-                    _chunks.emplace_back(
-                        std::vector<uint8_t>(_rxbuf.begin()+ws.header_size,
-                                             _rxbuf.begin()+ws.header_size+(size_t)ws.N));
+                    _chunks.emplace_back(frameData);
+
                     if (ws.fin)
                     {
                         emitMessage(_fragmentedMessageKind, getMergedChunks(),
@@ -624,13 +625,8 @@ namespace ix
             }
             else if (ws.opcode == wsheader_type::PING)
             {
-                unmaskReceiveBuffer(ws);
-
-                std::string pingData(_rxbuf.begin()+ws.header_size,
-                                     _rxbuf.begin()+ws.header_size + (size_t) ws.N);
-
                 // too large
-                if (pingData.size() > 125)
+                if (frameData.size() > 125)
                 {
                     // Unexpected frame type
                     close(WebSocketCloseConstants::kProtocolErrorCode,
@@ -642,29 +638,23 @@ namespace ix
                 {
                     // Reply back right away
                     bool compress = false;
-                    sendData(wsheader_type::PONG, pingData, compress);
+                    sendData(wsheader_type::PONG, frameData, compress);
                 }
 
-                emitMessage(MessageKind::PING, pingData, ws, onMessageCallback);
+                emitMessage(MessageKind::PING, frameData, ws, onMessageCallback);
             }
             else if (ws.opcode == wsheader_type::PONG)
             {
-                unmaskReceiveBuffer(ws);
-                std::string pongData(_rxbuf.begin()+ws.header_size,
-                                     _rxbuf.begin()+ws.header_size + (size_t) ws.N);
-
                 std::lock_guard<std::mutex> lck(_lastReceivePongTimePointMutex);
                 _lastReceivePongTimePoint = std::chrono::steady_clock::now();
 
-                emitMessage(MessageKind::PONG, pongData, ws, onMessageCallback);
+                emitMessage(MessageKind::PONG, frameData, ws, onMessageCallback);
             }
             else if (ws.opcode == wsheader_type::CLOSE)
             {
                 std::string reason;
                 uint16_t code = 0;
 
-                unmaskReceiveBuffer(ws);
-
                 if (ws.N >= 2)
                 {
                     // Extract the close code first, available as the first 2 bytes
@@ -674,8 +664,7 @@ namespace ix
                     // Get the reason.
                     if (ws.N > 2)
                     {
-                        reason.assign(_rxbuf.begin()+ws.header_size + 2,
-                                      _rxbuf.begin()+ws.header_size + (size_t) ws.N);
+                        reason = frameData.substr(2, frameData.size());
                     }
 
                     // Validate that the reason is proper utf-8. Autobahn 7.5.1
@@ -782,8 +771,7 @@ namespace ix
 
         for (auto&& chunk : _chunks)
         {
-            std::string str(chunk.begin(), chunk.end());
-            msg += str;
+            msg += chunk;
         }
 
         return msg;
diff --git a/ixwebsocket/IXWebSocketTransport.h b/ixwebsocket/IXWebSocketTransport.h
index 331d5fdf..54546a7d 100644
--- a/ixwebsocket/IXWebSocketTransport.h
+++ b/ixwebsocket/IXWebSocketTransport.h
@@ -149,7 +149,7 @@ namespace ix
         // messages (tested messages up to 700M) and we cannot put them in a single
         // buffer that is resized, as this operation can be slow when a buffer has its
         // size increased 2 fold, while appending to a list has a fixed cost.
-        std::list<std::vector<uint8_t>> _chunks;
+        std::list<std::string> _chunks;
 
         // Record the message kind (will be TEXT or BINARY) for a fragmented
         // message, present in the first chunk, since the final chunk will be a