• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 WebCore {
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