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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 // Note: custom allocators are not supported on VC6, since that compiler
9 // had trouble finding the function zlib_base::do_init.
10 
11 #ifndef BOOST_IOSTREAMS_ZLIB_HPP_INCLUDED
12 #define BOOST_IOSTREAMS_ZLIB_HPP_INCLUDED
13 
14 #if defined(_MSC_VER)
15 # pragma once
16 #endif
17 
18 #include <cassert>
19 #include <iosfwd>            // streamsize.
20 #include <memory>            // allocator, bad_alloc.
21 #include <new>
22 #include <boost/config.hpp>  // MSVC, STATIC_CONSTANT, DEDUCED_TYPENAME, DINKUM.
23 #include <boost/cstdint.hpp> // uint*_t
24 #include <boost/detail/workaround.hpp>
25 #include <boost/iostreams/constants.hpp>   // buffer size.
26 #include <boost/iostreams/detail/config/auto_link.hpp>
27 #include <boost/iostreams/detail/config/dyn_link.hpp>
28 #include <boost/iostreams/detail/config/wide_streams.hpp>
29 #include <boost/iostreams/detail/config/zlib.hpp>
30 #include <boost/iostreams/detail/ios.hpp>  // failure, streamsize.
31 #include <boost/iostreams/filter/symmetric.hpp>
32 #include <boost/iostreams/pipeline.hpp>
33 #include <boost/type_traits/is_same.hpp>
34 
35 // Must come last.
36 #ifdef BOOST_MSVC
37 # pragma warning(push)
38 # pragma warning(disable:4251 4275 4231 4660)         // Dependencies not exported.
39 #endif
40 #include <boost/config/abi_prefix.hpp>
41 
42 namespace boost { namespace iostreams {
43 
44 namespace zlib {
45                     // Typedefs
46 
47 typedef uint32_t uint;
48 typedef uint8_t byte;
49 typedef uint32_t ulong;
50 
51 // Prefix 'x' prevents symbols from being redefined when Z_PREFIX is defined
52 typedef void* (*xalloc_func)(void*, zlib::uint, zlib::uint);
53 typedef void (*xfree_func)(void*, void*);
54 
55                     // Compression levels
56 
57 BOOST_IOSTREAMS_DECL extern const int no_compression;
58 BOOST_IOSTREAMS_DECL extern const int best_speed;
59 BOOST_IOSTREAMS_DECL extern const int best_compression;
60 BOOST_IOSTREAMS_DECL extern const int default_compression;
61 
62                     // Compression methods
63 
64 BOOST_IOSTREAMS_DECL extern const int deflated;
65 
66                     // Compression strategies
67 
68 BOOST_IOSTREAMS_DECL extern const int default_strategy;
69 BOOST_IOSTREAMS_DECL extern const int filtered;
70 BOOST_IOSTREAMS_DECL extern const int huffman_only;
71 
72                     // Status codes
73 
74 BOOST_IOSTREAMS_DECL extern const int okay;
75 BOOST_IOSTREAMS_DECL extern const int stream_end;
76 BOOST_IOSTREAMS_DECL extern const int stream_error;
77 BOOST_IOSTREAMS_DECL extern const int version_error;
78 BOOST_IOSTREAMS_DECL extern const int data_error;
79 BOOST_IOSTREAMS_DECL extern const int mem_error;
80 BOOST_IOSTREAMS_DECL extern const int buf_error;
81 
82                     // Flush codes
83 
84 BOOST_IOSTREAMS_DECL extern const int finish;
85 BOOST_IOSTREAMS_DECL extern const int no_flush;
86 BOOST_IOSTREAMS_DECL extern const int sync_flush;
87 
88                     // Code for current OS
89 
90 //BOOST_IOSTREAMS_DECL extern const int os_code;
91 
92                     // Null pointer constant.
93 
94 const int null                               = 0;
95 
96                     // Default values
97 
98 const int default_window_bits                = 15;
99 const int default_mem_level                  = 8;
100 const bool default_crc                       = false;
101 const bool default_noheader                  = false;
102 
103 } // End namespace zlib.
104 
105 //
106 // Class name: zlib_params.
107 // Description: Encapsulates the parameters passed to deflateInit2
108 //      and inflateInit2 to customize compression and decompression.
109 //
110 struct zlib_params {
111 
112     // Non-explicit constructor.
zlib_paramsboost::iostreams::zlib_params113     zlib_params( int level_          = zlib::default_compression,
114                  int method_         = zlib::deflated,
115                  int window_bits_    = zlib::default_window_bits,
116                  int mem_level_      = zlib::default_mem_level,
117                  int strategy_       = zlib::default_strategy,
118                  bool noheader_      = zlib::default_noheader,
119                  bool calculate_crc_ = zlib::default_crc )
120         : level(level_), method(method_), window_bits(window_bits_),
121           mem_level(mem_level_), strategy(strategy_),
122           noheader(noheader_), calculate_crc(calculate_crc_)
123         { }
124     int level;
125     int method;
126     int window_bits;
127     int mem_level;
128     int strategy;
129     bool noheader;
130     bool calculate_crc;
131 };
132 
133 //
134 // Class name: zlib_error.
135 // Description: Subclass of std::ios::failure thrown to indicate
136 //     zlib errors other than out-of-memory conditions.
137 //
138 class BOOST_IOSTREAMS_DECL zlib_error : public BOOST_IOSTREAMS_FAILURE {
139 public:
140     explicit zlib_error(int error);
error() const141     int error() const { return error_; }
142     static void check BOOST_PREVENT_MACRO_SUBSTITUTION(int error);
143 private:
144     int error_;
145 };
146 
147 namespace detail {
148 
149 template<typename Alloc>
150 struct zlib_allocator_traits {
151 #ifndef BOOST_NO_STD_ALLOCATOR
152 #if defined(BOOST_NO_CXX11_ALLOCATOR)
153     typedef typename Alloc::template rebind<char>::other type;
154 #else
155     typedef typename std::allocator_traits<Alloc>::template rebind_alloc<char> type;
156 #endif
157 #else
158     typedef std::allocator<char> type;
159 #endif
160 };
161 
162 template< typename Alloc,
163           typename Base = // VC6 workaround (C2516)
164               BOOST_DEDUCED_TYPENAME zlib_allocator_traits<Alloc>::type >
165 struct zlib_allocator : private Base {
166 private:
167 #if defined(BOOST_NO_CXX11_ALLOCATOR) || defined(BOOST_NO_STD_ALLOCATOR)
168     typedef typename Base::size_type size_type;
169 #else
170     typedef typename std::allocator_traits<Base>::size_type size_type;
171 #endif
172 public:
173     BOOST_STATIC_CONSTANT(bool, custom =
174         (!is_same<std::allocator<char>, Base>::value));
175     typedef typename zlib_allocator_traits<Alloc>::type allocator_type;
176     static void* allocate(void* self, zlib::uint items, zlib::uint size);
177     static void deallocate(void* self, void* address);
178 };
179 
180 class BOOST_IOSTREAMS_DECL zlib_base {
181 public:
182     typedef char char_type;
183 protected:
184     zlib_base();
185     ~zlib_base();
stream()186     void* stream() { return stream_; }
187     template<typename Alloc>
init(const zlib_params & p,bool compress,zlib_allocator<Alloc> & zalloc)188     void init( const zlib_params& p,
189                bool compress,
190                zlib_allocator<Alloc>& zalloc )
191         {
192             bool custom = zlib_allocator<Alloc>::custom;
193             do_init( p, compress,
194                      custom ? zlib_allocator<Alloc>::allocate : 0,
195                      custom ? zlib_allocator<Alloc>::deallocate : 0,
196                      &zalloc );
197         }
198     void before( const char*& src_begin, const char* src_end,
199                  char*& dest_begin, char* dest_end );
200     void after( const char*& src_begin, char*& dest_begin,
201                 bool compress );
202     int xdeflate(int flush);  // Prefix 'x' prevents symbols from being
203     int xinflate(int flush);  // redefined when Z_PREFIX is defined
204     void reset(bool compress, bool realloc);
205 public:
crc() const206     zlib::ulong crc() const { return crc_; }
total_in() const207     int total_in() const { return total_in_; }
total_out() const208     int total_out() const { return total_out_; }
209 private:
210     void do_init( const zlib_params& p, bool compress,
211                   zlib::xalloc_func,
212                   zlib::xfree_func,
213                   void* derived );
214     void*        stream_;         // Actual type: z_stream*.
215     bool         calculate_crc_;
216     zlib::ulong  crc_;
217     zlib::ulong  crc_imp_;
218     int          total_in_;
219     int          total_out_;
220 };
221 
222 //
223 // Template name: zlib_compressor_impl
224 // Description: Model of C-Style Filte implementing compression by
225 //      delegating to the zlib function deflate.
226 //
227 template<typename Alloc = std::allocator<char> >
228 class zlib_compressor_impl : public zlib_base, public zlib_allocator<Alloc> {
229 public:
230     zlib_compressor_impl(const zlib_params& = zlib::default_compression);
231     ~zlib_compressor_impl();
232     bool filter( const char*& src_begin, const char* src_end,
233                  char*& dest_begin, char* dest_end, bool flush );
234     void close();
235 };
236 
237 //
238 // Template name: zlib_compressor
239 // Description: Model of C-Style Filte implementing decompression by
240 //      delegating to the zlib function inflate.
241 //
242 template<typename Alloc = std::allocator<char> >
243 class zlib_decompressor_impl : public zlib_base, public zlib_allocator<Alloc> {
244 public:
245     zlib_decompressor_impl(const zlib_params&);
246     zlib_decompressor_impl(int window_bits = zlib::default_window_bits);
247     ~zlib_decompressor_impl();
248     bool filter( const char*& begin_in, const char* end_in,
249                  char*& begin_out, char* end_out, bool flush );
250     void close();
eof() const251     bool eof() const { return eof_; }
252 private:
253     bool eof_;
254 };
255 
256 } // End namespace detail.
257 
258 //
259 // Template name: zlib_compressor
260 // Description: Model of InputFilter and OutputFilter implementing
261 //      compression using zlib.
262 //
263 template<typename Alloc = std::allocator<char> >
264 struct basic_zlib_compressor
265     : symmetric_filter<detail::zlib_compressor_impl<Alloc>, Alloc>
266 {
267 private:
268     typedef detail::zlib_compressor_impl<Alloc>         impl_type;
269     typedef symmetric_filter<impl_type, Alloc>  base_type;
270 public:
271     typedef typename base_type::char_type               char_type;
272     typedef typename base_type::category                category;
273     basic_zlib_compressor( const zlib_params& = zlib::default_compression,
274                            std::streamsize buffer_size = default_device_buffer_size );
crcboost::iostreams::basic_zlib_compressor275     zlib::ulong crc() { return this->filter().crc(); }
total_inboost::iostreams::basic_zlib_compressor276     int total_in() {  return this->filter().total_in(); }
277 };
278 BOOST_IOSTREAMS_PIPABLE(basic_zlib_compressor, 1)
279 
280 typedef basic_zlib_compressor<> zlib_compressor;
281 
282 //
283 // Template name: zlib_decompressor
284 // Description: Model of InputFilter and OutputFilter implementing
285 //      decompression using zlib.
286 //
287 template<typename Alloc = std::allocator<char> >
288 struct basic_zlib_decompressor
289     : symmetric_filter<detail::zlib_decompressor_impl<Alloc>, Alloc>
290 {
291 private:
292     typedef detail::zlib_decompressor_impl<Alloc>       impl_type;
293     typedef symmetric_filter<impl_type, Alloc>  base_type;
294 public:
295     typedef typename base_type::char_type               char_type;
296     typedef typename base_type::category                category;
297     basic_zlib_decompressor( int window_bits = zlib::default_window_bits,
298                              std::streamsize buffer_size = default_device_buffer_size );
299     basic_zlib_decompressor( const zlib_params& p,
300                              std::streamsize buffer_size = default_device_buffer_size );
crcboost::iostreams::basic_zlib_decompressor301     zlib::ulong crc() { return this->filter().crc(); }
total_outboost::iostreams::basic_zlib_decompressor302     int total_out() {  return this->filter().total_out(); }
eofboost::iostreams::basic_zlib_decompressor303     bool eof() { return this->filter().eof(); }
304 };
305 BOOST_IOSTREAMS_PIPABLE(basic_zlib_decompressor, 1)
306 
307 typedef basic_zlib_decompressor<> zlib_decompressor;
308 
309 //----------------------------------------------------------------------------//
310 
311 //------------------Implementation of zlib_allocator--------------------------//
312 
313 namespace detail {
314 
315 template<typename Alloc, typename Base>
allocate(void * self,zlib::uint items,zlib::uint size)316 void* zlib_allocator<Alloc, Base>::allocate
317     (void* self, zlib::uint items, zlib::uint size)
318 {
319     size_type len = items * size;
320     char* ptr =
321         static_cast<allocator_type*>(self)->allocate
322             (len + sizeof(size_type)
323             #if BOOST_WORKAROUND(BOOST_DINKUMWARE_STDLIB, == 1)
324                 , (char*)0
325             #endif
326             );
327     *reinterpret_cast<size_type*>(ptr) = len;
328     return ptr + sizeof(size_type);
329 }
330 
331 template<typename Alloc, typename Base>
deallocate(void * self,void * address)332 void zlib_allocator<Alloc, Base>::deallocate(void* self, void* address)
333 {
334     char* ptr = reinterpret_cast<char*>(address) - sizeof(size_type);
335     size_type len = *reinterpret_cast<size_type*>(ptr) + sizeof(size_type);
336     static_cast<allocator_type*>(self)->deallocate(ptr, len);
337 }
338 
339 //------------------Implementation of zlib_compressor_impl--------------------//
340 
341 template<typename Alloc>
zlib_compressor_impl(const zlib_params & p)342 zlib_compressor_impl<Alloc>::zlib_compressor_impl(const zlib_params& p)
343 { init(p, true, static_cast<zlib_allocator<Alloc>&>(*this)); }
344 
345 template<typename Alloc>
~zlib_compressor_impl()346 zlib_compressor_impl<Alloc>::~zlib_compressor_impl()
347 { reset(true, false); }
348 
349 template<typename Alloc>
filter(const char * & src_begin,const char * src_end,char * & dest_begin,char * dest_end,bool flush)350 bool zlib_compressor_impl<Alloc>::filter
351     ( const char*& src_begin, const char* src_end,
352       char*& dest_begin, char* dest_end, bool flush )
353 {
354     before(src_begin, src_end, dest_begin, dest_end);
355     int result = xdeflate(flush ? zlib::finish : zlib::no_flush);
356     after(src_begin, dest_begin, true);
357     zlib_error::check BOOST_PREVENT_MACRO_SUBSTITUTION(result);
358     return result != zlib::stream_end;
359 }
360 
361 template<typename Alloc>
close()362 void zlib_compressor_impl<Alloc>::close() { reset(true, true); }
363 
364 //------------------Implementation of zlib_decompressor_impl------------------//
365 
366 template<typename Alloc>
zlib_decompressor_impl(const zlib_params & p)367 zlib_decompressor_impl<Alloc>::zlib_decompressor_impl(const zlib_params& p)
368   : eof_(false)
369 { init(p, false, static_cast<zlib_allocator<Alloc>&>(*this)); }
370 
371 template<typename Alloc>
~zlib_decompressor_impl()372 zlib_decompressor_impl<Alloc>::~zlib_decompressor_impl()
373 { reset(false, false); }
374 
375 template<typename Alloc>
zlib_decompressor_impl(int window_bits)376 zlib_decompressor_impl<Alloc>::zlib_decompressor_impl(int window_bits)
377 {
378     zlib_params p;
379     p.window_bits = window_bits;
380     init(p, false, static_cast<zlib_allocator<Alloc>&>(*this));
381 }
382 
383 template<typename Alloc>
filter(const char * & src_begin,const char * src_end,char * & dest_begin,char * dest_end,bool)384 bool zlib_decompressor_impl<Alloc>::filter
385     ( const char*& src_begin, const char* src_end,
386       char*& dest_begin, char* dest_end, bool /* flush */ )
387 {
388     before(src_begin, src_end, dest_begin, dest_end);
389     int result = xinflate(zlib::sync_flush);
390     after(src_begin, dest_begin, false);
391     zlib_error::check BOOST_PREVENT_MACRO_SUBSTITUTION(result);
392     return !(eof_ = result == zlib::stream_end);
393 }
394 
395 template<typename Alloc>
close()396 void zlib_decompressor_impl<Alloc>::close() {
397     eof_ = false;
398     reset(false, true);
399 }
400 
401 } // End namespace detail.
402 
403 //------------------Implementation of zlib_decompressor-----------------------//
404 
405 template<typename Alloc>
basic_zlib_compressor(const zlib_params & p,std::streamsize buffer_size)406 basic_zlib_compressor<Alloc>::basic_zlib_compressor
407     (const zlib_params& p, std::streamsize buffer_size)
408     : base_type(buffer_size, p) { }
409 
410 //------------------Implementation of zlib_decompressor-----------------------//
411 
412 template<typename Alloc>
basic_zlib_decompressor(int window_bits,std::streamsize buffer_size)413 basic_zlib_decompressor<Alloc>::basic_zlib_decompressor
414     (int window_bits, std::streamsize buffer_size)
415     : base_type(buffer_size, window_bits) { }
416 
417 template<typename Alloc>
basic_zlib_decompressor(const zlib_params & p,std::streamsize buffer_size)418 basic_zlib_decompressor<Alloc>::basic_zlib_decompressor
419     (const zlib_params& p, std::streamsize buffer_size)
420     : base_type(buffer_size, p) { }
421 
422 //----------------------------------------------------------------------------//
423 
424 } } // End namespaces iostreams, boost.
425 
426 #include <boost/config/abi_suffix.hpp> // Pops abi_suffix.hpp pragmas.
427 #ifdef BOOST_MSVC
428 # pragma warning(pop)
429 #endif
430 
431 #endif // #ifndef BOOST_IOSTREAMS_ZLIB_HPP_INCLUDED
432