1 /* 2 * Copyright (C) 2012 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef WebSocketDeflater_h 32 #define WebSocketDeflater_h 33 34 #include "wtf/Noncopyable.h" 35 #include "wtf/OwnPtr.h" 36 #include "wtf/PassOwnPtr.h" 37 #include "wtf/Vector.h" 38 39 struct z_stream_s; 40 typedef z_stream_s z_stream; 41 42 namespace blink { 43 44 class WebSocketDeflater { 45 WTF_MAKE_FAST_ALLOCATED; 46 public: 47 // This enum is reused for histogram. When this needs to be modified, add a 48 // new enum for histogram and convert mode values into values in the new 49 // enum to keep new data consistent with old one. 50 enum ContextTakeOverMode { 51 DoNotTakeOverContext, 52 TakeOverContext, 53 ContextTakeOverModeMax, 54 }; 55 static PassOwnPtr<WebSocketDeflater> create(int windowBits, ContextTakeOverMode = TakeOverContext); 56 57 ~WebSocketDeflater(); 58 59 bool initialize(); 60 bool addBytes(const char*, size_t); 61 bool finish(); data()62 const char* data() { return m_buffer.data(); } size()63 size_t size() const { return m_buffer.size(); } 64 // Reset the deflate result. 65 void softReset(); 66 // Reset the deflate result and internal state if the take over mode is DoNotTakeOverContext. 67 void reset(); 68 69 private: 70 WebSocketDeflater(int windowBits, ContextTakeOverMode); 71 72 int m_windowBits; 73 ContextTakeOverMode m_contextTakeOverMode; 74 bool m_isBytesAdded; 75 Vector<char> m_buffer; 76 OwnPtr<z_stream> m_stream; 77 }; 78 79 class WebSocketInflater { 80 WTF_MAKE_FAST_ALLOCATED; 81 public: 82 static PassOwnPtr<WebSocketInflater> create(int windowBits = 15); 83 84 ~WebSocketInflater(); 85 86 bool initialize(); 87 bool addBytes(const char*, size_t); 88 bool finish(); data()89 const char* data() { return m_buffer.data(); } size()90 size_t size() const { return m_buffer.size(); } 91 // Reset the inflate result. 92 void reset(); 93 94 private: 95 explicit WebSocketInflater(int windowBits); 96 97 int m_windowBits; 98 Vector<char> m_buffer; 99 OwnPtr<z_stream> m_stream; 100 }; 101 102 } 103 104 #endif // WebSocketDeflater_h 105