Add support for zero-copy transfer of unchanged bytes.

net/spdy/spdy_protocol.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file contains some protocol structures for use with SPDY 3 and HTTP 2
 // The SPDY 3 spec can be found at:
 // http://dev.chromium.org/spdy/spdy-protocol/spdy-protocol-draft3
 
 #ifndef NET_SPDY_SPDY_PROTOCOL_H_
 #define NET_SPDY_SPDY_PROTOCOL_H_
@@ skipping 1179 matching lines @@
     }
   }
 
   // Provides access to the frame bytes, which is a buffer containing the frame
   // packed as expected for sending over the wire.
   char* data() const { return frame_; }
 
   // Returns the actual size of the underlying buffer.
   size_t size() const { return size_; }
 
+  // Returns a buffer containing the contents of the frame, of which the caller
+  // takes ownership, and clears this SpdySerializedFrame.
+  char* ReleaseBuffer() {
+    char* buffer;
+    if (owns_buffer_) {
+      // If the buffer is owned, relinquish ownership to the caller.
+      buffer = frame_;
+      owns_buffer_ = false;
+    } else {
+      // Otherwise, we need to make a copy to give to the caller.
+      buffer = new char[size_];
+      memcpy(buffer, frame_, size_);
+    }
+    *this = SpdySerializedFrame();
+    return buffer;
+  }
+
  protected:
   char* frame_;
 
  private:
   size_t size_;
   bool owns_buffer_;
   DISALLOW_COPY_AND_ASSIGN(SpdySerializedFrame);
 };
 
 // This interface is for classes that want to process SpdyFrameIRs without
@@ skipping 21 matching lines @@
   SpdyFrameVisitor() {}
   virtual ~SpdyFrameVisitor() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SpdyFrameVisitor);
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_SPDY_PROTOCOL_H_