1 /**************************************************************************
3 * Copyright 2011 Zack Rusin
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 **************************************************************************/
27 #ifndef TRACE_SNAPPYFILE_HPP
28 #define TRACE_SNAPPYFILE_HPP
32 #include "trace_file.hpp"
43 #define SNAPPY_CHUNK_SIZE (1 * 1024 * 1024)
45 #define SNAPPY_BYTE1 'a'
46 #define SNAPPY_BYTE2 't'
49 class SnappyFile : public File {
51 SnappyFile(const std::string &filename = std::string(),
52 File::Mode mode = File::Read);
53 virtual ~SnappyFile();
55 virtual bool supportsOffsets() const;
56 virtual File::Offset currentOffset();
57 virtual void setCurrentOffset(const File::Offset &offset);
59 virtual bool rawOpen(const std::string &filename, File::Mode mode);
60 virtual bool rawWrite(const void *buffer, size_t length);
61 virtual bool rawRead(void *buffer, size_t length);
62 virtual int rawGetc();
63 virtual void rawClose();
64 virtual void rawFlush();
65 virtual bool rawSkip(size_t length);
66 virtual int rawPercentRead();
69 inline size_t usedCacheSize() const
71 assert(m_cachePtr >= m_cache);
72 return m_cachePtr - m_cache;
74 inline size_t freeCacheSize() const
76 assert(m_cacheSize >= usedCacheSize());
77 if (m_cacheSize > 0) {
78 return m_cacheSize - usedCacheSize();
83 inline bool endOfData() const
85 return m_stream.eof() && freeCacheSize() == 0;
87 void flushWriteCache();
88 void flushReadCache(size_t skipLength = 0);
89 void createCache(size_t size);
90 void writeCompressedLength(size_t length);
91 size_t readCompressedLength();
93 std::fstream m_stream;
98 char *m_compressedCache;
100 File::Offset m_currentOffset;
101 std::streampos m_endPos;
106 #endif // TRACE_SNAPPYFILE_HPP