| // Copyright 2013 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. |
| |
| #ifndef NET_WEBSOCKETS_WEBSOCKET_DEFLATER_H_ |
| #define NET_WEBSOCKETS_WEBSOCKET_DEFLATER_H_ |
| |
| #include <stddef.h> |
| |
| #include <memory> |
| #include <vector> |
| |
| #include "base/containers/circular_deque.h" |
| #include "base/macros.h" |
| #include "base/memory/scoped_refptr.h" |
| #include "net/base/net_export.h" |
| |
| extern "C" struct z_stream_s; |
| |
| namespace net { |
| |
| class IOBufferWithSize; |
| |
| class NET_EXPORT_PRIVATE WebSocketDeflater { |
| public: |
| enum ContextTakeOverMode { |
| DO_NOT_TAKE_OVER_CONTEXT, |
| TAKE_OVER_CONTEXT, |
| NUM_CONTEXT_TAKEOVER_MODE_TYPES, |
| }; |
| |
| explicit WebSocketDeflater(ContextTakeOverMode mode); |
| ~WebSocketDeflater(); |
| |
| // Returns true if there is no error and false otherwise. |
| // This function must be called exactly once before calling any of |
| // following methods. |
| // |window_bits| must be between 8 and 15 (both inclusive). |
| bool Initialize(int window_bits); |
| |
| // Adds bytes to |stream_|. |
| // Returns true if there is no error and false otherwise. |
| bool AddBytes(const char* data, size_t size); |
| |
| // Flushes the current processing data. |
| // Returns true if there is no error and false otherwise. |
| bool Finish(); |
| |
| // Pushes "\x00\x00\xff\xff" to the end of the buffer. |
| void PushSyncMark(); |
| |
| // Returns the current deflated output. |
| // If the current output is larger than |size| bytes, |
| // returns the first |size| bytes of the current output. |
| // The returned bytes will be dropped from the current output and never be |
| // returned thereafter. |
| scoped_refptr<IOBufferWithSize> GetOutput(size_t size); |
| |
| // Returns the size of the current deflated output. |
| size_t CurrentOutputSize() const { return buffer_.size(); } |
| |
| private: |
| void ResetContext(); |
| int Deflate(int flush); |
| |
| std::unique_ptr<z_stream_s> stream_; |
| ContextTakeOverMode mode_; |
| base::circular_deque<char> buffer_; |
| std::vector<char> fixed_buffer_; |
| // true if bytes were added after last Finish(). |
| bool are_bytes_added_; |
| |
| DISALLOW_COPY_AND_ASSIGN(WebSocketDeflater); |
| }; |
| |
| } // namespace net |
| |
| #endif // NET_WEBSOCKETS_WEBSOCKET_DEFLATER_H_ |