1 | // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com) |
2 | // (C) Copyright 2003-2007 Jonathan Turkanis |
3 | // Distributed under the Boost Software License, Version 1.0. (See accompanying |
4 | // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.) |
5 | |
6 | // See http://www.boost.org/libs/iostreams for documentation. |
7 | |
8 | // To configure Boost to work with zlib, see the |
9 | // installation instructions here: |
10 | // http://boost.org/libs/iostreams/doc/index.html?path=7 |
11 | |
12 | // Define BOOST_IOSTREAMS_SOURCE so that <boost/iostreams/detail/config.hpp> |
13 | // knows that we are building the library (possibly exporting code), rather |
14 | // than using it (possibly importing code). |
15 | #define BOOST_IOSTREAMS_SOURCE |
16 | |
17 | #include <boost/throw_exception.hpp> |
18 | #include <boost/iostreams/detail/config/dyn_link.hpp> |
19 | #include <boost/iostreams/filter/zlib.hpp> |
20 | #include "zlib.h" // Jean-loup Gailly's and Mark Adler's "zlib.h" header. |
21 | // To configure Boost to work with zlib, see the |
22 | // installation instructions here: |
23 | // http://boost.org/libs/iostreams/doc/index.html?path=7 |
24 | |
25 | namespace boost { namespace iostreams { |
26 | |
27 | namespace zlib { |
28 | |
29 | // Compression levels |
30 | |
31 | const int no_compression = Z_NO_COMPRESSION; |
32 | const int best_speed = Z_BEST_SPEED; |
33 | const int best_compression = Z_BEST_COMPRESSION; |
34 | const int default_compression = Z_DEFAULT_COMPRESSION; |
35 | |
36 | // Compression methods |
37 | |
38 | const int deflated = Z_DEFLATED; |
39 | |
40 | // Compression strategies |
41 | |
42 | const int default_strategy = Z_DEFAULT_STRATEGY; |
43 | const int filtered = Z_FILTERED; |
44 | const int huffman_only = Z_HUFFMAN_ONLY; |
45 | |
46 | // Status codes |
47 | |
48 | const int okay = Z_OK; |
49 | const int stream_end = Z_STREAM_END; |
50 | const int stream_error = Z_STREAM_ERROR; |
51 | const int version_error = Z_VERSION_ERROR; |
52 | const int data_error = Z_DATA_ERROR; |
53 | const int mem_error = Z_MEM_ERROR; |
54 | const int buf_error = Z_BUF_ERROR; |
55 | |
56 | // Flush codes |
57 | |
58 | const int finish = Z_FINISH; |
59 | const int no_flush = Z_NO_FLUSH; |
60 | const int sync_flush = Z_SYNC_FLUSH; |
61 | |
62 | // Code for current OS |
63 | |
64 | //const int os_code = OS_CODE; |
65 | |
66 | } // End namespace zlib. |
67 | |
68 | //------------------Implementation of zlib_error------------------------------// |
69 | |
70 | zlib_error::zlib_error(int error) |
71 | : BOOST_IOSTREAMS_FAILURE("zlib error" ), error_(error) |
72 | { } |
73 | |
74 | void zlib_error::check BOOST_PREVENT_MACRO_SUBSTITUTION(int error) |
75 | { |
76 | switch (error) { |
77 | case Z_OK: |
78 | case Z_STREAM_END: |
79 | //case Z_BUF_ERROR: |
80 | return; |
81 | case Z_MEM_ERROR: |
82 | boost::throw_exception(e: std::bad_alloc()); |
83 | default: |
84 | boost::throw_exception(e: zlib_error(error)); |
85 | ; |
86 | } |
87 | } |
88 | |
89 | //------------------Implementation of zlib_base-------------------------------// |
90 | |
91 | namespace detail { |
92 | |
93 | zlib_base::zlib_base() |
94 | : stream_(new z_stream), calculate_crc_(false), crc_(0), crc_imp_(0), |
95 | total_in_(0), total_out_(0) |
96 | { } |
97 | |
98 | zlib_base::~zlib_base() { delete static_cast<z_stream*>(stream_); } |
99 | |
100 | void zlib_base::before( const char*& src_begin, const char* src_end, |
101 | char*& dest_begin, char* dest_end ) |
102 | { |
103 | z_stream* s = static_cast<z_stream*>(stream_); |
104 | s->next_in = reinterpret_cast<zlib::byte*>(const_cast<char*>(src_begin)); |
105 | s->avail_in = static_cast<zlib::uint>(src_end - src_begin); |
106 | s->next_out = reinterpret_cast<zlib::byte*>(dest_begin); |
107 | s->avail_out= static_cast<zlib::uint>(dest_end - dest_begin); |
108 | } |
109 | |
110 | void zlib_base::after(const char*& src_begin, char*& dest_begin, bool compress) |
111 | { |
112 | z_stream* s = static_cast<z_stream*>(stream_); |
113 | const char* next_in = reinterpret_cast<const char*>(s->next_in); |
114 | char* next_out = reinterpret_cast<char*>(s->next_out); |
115 | if (calculate_crc_) { |
116 | const zlib::byte* buf = compress ? |
117 | reinterpret_cast<const zlib::byte*>(src_begin) : |
118 | reinterpret_cast<const zlib::byte*>( |
119 | const_cast<const char*>(dest_begin) |
120 | ); |
121 | zlib::uint length = compress ? |
122 | static_cast<zlib::uint>(next_in - src_begin) : |
123 | static_cast<zlib::uint>(next_out - dest_begin); |
124 | crc_ = crc_imp_ = crc32(crc: crc_imp_, buf, len: length); |
125 | } |
126 | total_in_ = s->total_in; |
127 | total_out_ = s->total_out; |
128 | src_begin = next_in; |
129 | dest_begin = next_out; |
130 | } |
131 | |
132 | int zlib_base::xdeflate(int flush) |
133 | { |
134 | return ::deflate(strm: static_cast<z_stream*>(stream_), flush); |
135 | } |
136 | |
137 | int zlib_base::xinflate(int flush) |
138 | { |
139 | return ::inflate(strm: static_cast<z_stream*>(stream_), flush); |
140 | } |
141 | |
142 | void zlib_base::reset(bool compress, bool realloc) |
143 | { |
144 | z_stream* s = static_cast<z_stream*>(stream_); |
145 | // Undiagnosed bug: |
146 | // deflateReset(), etc., return Z_DATA_ERROR |
147 | //zlib_error::check BOOST_PREVENT_MACRO_SUBSTITUTION( |
148 | realloc ? |
149 | (compress ? deflateReset(strm: s) : inflateReset(strm: s)) : |
150 | (compress ? deflateEnd(strm: s) : inflateEnd(strm: s)) |
151 | ; |
152 | //); |
153 | crc_imp_ = 0; |
154 | } |
155 | |
156 | void zlib_base::do_init |
157 | ( const zlib_params& p, bool compress, |
158 | zlib::xalloc_func /* alloc */, zlib::xfree_func /* free*/, |
159 | void* derived ) |
160 | { |
161 | calculate_crc_ = p.calculate_crc; |
162 | z_stream* s = static_cast<z_stream*>(stream_); |
163 | |
164 | // Current interface for customizing memory management |
165 | // is non-conforming and has been disabled: |
166 | // s->zalloc = alloc; |
167 | // s->zfree = free; |
168 | s->zalloc = 0; |
169 | s->zfree = 0; |
170 | s->opaque = derived; |
171 | int window_bits = p.noheader? -p.window_bits : p.window_bits; |
172 | zlib_error::check BOOST_PREVENT_MACRO_SUBSTITUTION( |
173 | error: compress ? |
174 | deflateInit2( s, |
175 | p.level, |
176 | p.method, |
177 | window_bits, |
178 | p.mem_level, |
179 | p.strategy ) : |
180 | inflateInit2(s, window_bits) |
181 | ); |
182 | } |
183 | |
184 | } // End namespace detail. |
185 | |
186 | //----------------------------------------------------------------------------// |
187 | |
188 | } } // End namespaces iostreams, boost. |
189 | |