prevent copying of buffers

include/connectionimpl.h

@@ -348,7 +348,7 @@ public:
      *
      *  @param  buffer      the buffer with data to send
      */
-    bool send(const CopiedBuffer &buffer);
+    bool send(CopiedBuffer &&buffer);
 
     /**
      *  Get a channel by its identifier

include/copiedbuffer.h

@@ -82,17 +82,10 @@ public:
     }
 
     /**
-     *  Copy constructor
+     *  Disabled copy constructor to prevent expensive copy operations
      *  @param  that
      */
-    CopiedBuffer(const CopiedBuffer &that) :
-        _capacity(that._capacity),
-        _buffer((char *)malloc(_capacity)),
-        _size(that._size)
-    {
-        // copy the data
-        memcpy(_buffer, that._buffer, _size);
-    }
+    CopiedBuffer(const CopiedBuffer &that) = delete;
 
     /**
      *  Move constructor

src/channelimpl.cpp

@@ -727,15 +727,15 @@ void ChannelImpl::onSynchronized()
     while (_connection && !_synchronous && !_queue.empty())
     {
         // retrieve the first buffer and synchronous
-        const auto &pair = _queue.front();
+        auto &pair = _queue.front();
 
         // mark as synchronous if necessary
         _synchronous = pair.first;
 
         // send it over the connection
-        _connection->send(pair.second);
+        _connection->send(std::move(pair.second));
 
-        // the user space handler may have destructed the channel
+        // the user space handler may have destructed this channel object
         if (!monitor.valid()) return;
 
         // remove from the list

src/connectionimpl.cpp

@@ -353,7 +353,7 @@ bool ConnectionImpl::send(const Frame &frame)
  *
  *  @param  buffer      the buffer with data to send
  */
-bool ConnectionImpl::send(const CopiedBuffer &buffer)
+bool ConnectionImpl::send(CopiedBuffer &&buffer)
 {
     // this only works when we are already connected
     if (_state != state_connected) return false;
@@ -367,7 +367,7 @@ bool ConnectionImpl::send(const CopiedBuffer &buffer)
     else
     {
         // add to the list of waiting buffers
-        _queue.push(buffer);
+        _queue.emplace(std::move(buffer));
     }
 
     // done