xref: /freebsd/contrib/xz/src/liblzma/api/lzma.h (revision a57ca37dd1848cd42844d9082c4a74c2ed57f68a)
1 /**
2  * \file        api/lzma.h
3  * \brief       The public API of liblzma data compression library
4  * \mainpage
5  *
6  * liblzma is a public domain general-purpose data compression library with
7  * a zlib-like API. The native file format is .xz, but also the old .lzma
8  * format and raw (no headers) streams are supported. Multiple compression
9  * algorithms (filters) are supported. Currently LZMA2 is the primary filter.
10  *
11  * liblzma is part of XZ Utils <https://tukaani.org/xz/>. XZ Utils includes
12  * a gzip-like command line tool named xz and some other tools. XZ Utils
13  * is developed and maintained by Lasse Collin and Jia Tan.
14  *
15  * Major parts of liblzma are based on Igor Pavlov's public domain LZMA SDK
16  * <https://7-zip.org/sdk.html>.
17  *
18  * The SHA-256 implementation is based on the public domain code found from
19  * 7-Zip <https://7-zip.org/>, which has a modified version of the public
20  * domain SHA-256 code found from Crypto++ <https://www.cryptopp.com/>.
21  * The SHA-256 code in Crypto++ was written by Kevin Springle and Wei Dai.
22  */
23 
24 /*
25  * Author: Lasse Collin
26  *
27  * This file has been put into the public domain.
28  * You can do whatever you want with this file.
29  */
30 
31 #ifndef LZMA_H
32 #define LZMA_H
33 
34 /*****************************
35  * Required standard headers *
36  *****************************/
37 
38 /*
39  * liblzma API headers need some standard types and macros. To allow
40  * including lzma.h without requiring the application to include other
41  * headers first, lzma.h includes the required standard headers unless
42  * they already seem to be included already or if LZMA_MANUAL_HEADERS
43  * has been defined.
44  *
45  * Here's what types and macros are needed and from which headers:
46  *  - stddef.h: size_t, NULL
47  *  - stdint.h: uint8_t, uint32_t, uint64_t, UINT32_C(n), uint64_C(n),
48  *    UINT32_MAX, UINT64_MAX
49  *
50  * However, inttypes.h is a little more portable than stdint.h, although
51  * inttypes.h declares some unneeded things compared to plain stdint.h.
52  *
53  * The hacks below aren't perfect, specifically they assume that inttypes.h
54  * exists and that it typedefs at least uint8_t, uint32_t, and uint64_t,
55  * and that, in case of incomplete inttypes.h, unsigned int is 32-bit.
56  * If the application already takes care of setting up all the types and
57  * macros properly (for example by using gnulib's stdint.h or inttypes.h),
58  * we try to detect that the macros are already defined and don't include
59  * inttypes.h here again. However, you may define LZMA_MANUAL_HEADERS to
60  * force this file to never include any system headers.
61  *
62  * Some could argue that liblzma API should provide all the required types,
63  * for example lzma_uint64, LZMA_UINT64_C(n), and LZMA_UINT64_MAX. This was
64  * seen as an unnecessary mess, since most systems already provide all the
65  * necessary types and macros in the standard headers.
66  *
67  * Note that liblzma API still has lzma_bool, because using stdbool.h would
68  * break C89 and C++ programs on many systems. sizeof(bool) in C99 isn't
69  * necessarily the same as sizeof(bool) in C++.
70  */
71 
72 #ifndef LZMA_MANUAL_HEADERS
73 	/*
74 	 * I suppose this works portably also in C++. Note that in C++,
75 	 * we need to get size_t into the global namespace.
76 	 */
77 #	include <stddef.h>
78 
79 	/*
80 	 * Skip inttypes.h if we already have all the required macros. If we
81 	 * have the macros, we assume that we have the matching typedefs too.
82 	 */
83 #	if !defined(UINT32_C) || !defined(UINT64_C) \
84 			|| !defined(UINT32_MAX) || !defined(UINT64_MAX)
85 		/*
86 		 * MSVC versions older than 2013 have no C99 support, and
87 		 * thus they cannot be used to compile liblzma. Using an
88 		 * existing liblzma.dll with old MSVC can work though(*),
89 		 * but we need to define the required standard integer
90 		 * types here in a MSVC-specific way.
91 		 *
92 		 * (*) If you do this, the existing liblzma.dll probably uses
93 		 *     a different runtime library than your MSVC-built
94 		 *     application. Mixing runtimes is generally bad, but
95 		 *     in this case it should work as long as you avoid
96 		 *     the few rarely-needed liblzma functions that allocate
97 		 *     memory and expect the caller to free it using free().
98 		 */
99 #		if defined(_WIN32) && defined(_MSC_VER) && _MSC_VER < 1800
100 			typedef unsigned __int8 uint8_t;
101 			typedef unsigned __int32 uint32_t;
102 			typedef unsigned __int64 uint64_t;
103 #		else
104 			/* Use the standard inttypes.h. */
105 #			ifdef __cplusplus
106 				/*
107 				 * C99 sections 7.18.2 and 7.18.4 specify
108 				 * that C++ implementations define the limit
109 				 * and constant macros only if specifically
110 				 * requested. Note that if you want the
111 				 * format macros (PRIu64 etc.) too, you need
112 				 * to define __STDC_FORMAT_MACROS before
113 				 * including lzma.h, since re-including
114 				 * inttypes.h with __STDC_FORMAT_MACROS
115 				 * defined doesn't necessarily work.
116 				 */
117 #				ifndef __STDC_LIMIT_MACROS
118 #					define __STDC_LIMIT_MACROS 1
119 #				endif
120 #				ifndef __STDC_CONSTANT_MACROS
121 #					define __STDC_CONSTANT_MACROS 1
122 #				endif
123 #			endif
124 
125 #			include <inttypes.h>
126 #		endif
127 
128 		/*
129 		 * Some old systems have only the typedefs in inttypes.h, and
130 		 * lack all the macros. For those systems, we need a few more
131 		 * hacks. We assume that unsigned int is 32-bit and unsigned
132 		 * long is either 32-bit or 64-bit. If these hacks aren't
133 		 * enough, the application has to setup the types manually
134 		 * before including lzma.h.
135 		 */
136 #		ifndef UINT32_C
137 #			if defined(_WIN32) && defined(_MSC_VER)
138 #				define UINT32_C(n) n ## UI32
139 #			else
140 #				define UINT32_C(n) n ## U
141 #			endif
142 #		endif
143 
144 #		ifndef UINT64_C
145 #			if defined(_WIN32) && defined(_MSC_VER)
146 #				define UINT64_C(n) n ## UI64
147 #			else
148 				/* Get ULONG_MAX. */
149 #				include <limits.h>
150 #				if ULONG_MAX == 4294967295UL
151 #					define UINT64_C(n) n ## ULL
152 #				else
153 #					define UINT64_C(n) n ## UL
154 #				endif
155 #			endif
156 #		endif
157 
158 #		ifndef UINT32_MAX
159 #			define UINT32_MAX (UINT32_C(4294967295))
160 #		endif
161 
162 #		ifndef UINT64_MAX
163 #			define UINT64_MAX (UINT64_C(18446744073709551615))
164 #		endif
165 #	endif
166 #endif /* ifdef LZMA_MANUAL_HEADERS */
167 
168 
169 /******************
170  * LZMA_API macro *
171  ******************/
172 
173 /*
174  * Some systems require that the functions and function pointers are
175  * declared specially in the headers. LZMA_API_IMPORT is for importing
176  * symbols and LZMA_API_CALL is to specify the calling convention.
177  *
178  * By default it is assumed that the application will link dynamically
179  * against liblzma. #define LZMA_API_STATIC in your application if you
180  * want to link against static liblzma. If you don't care about portability
181  * to operating systems like Windows, or at least don't care about linking
182  * against static liblzma on them, don't worry about LZMA_API_STATIC. That
183  * is, most developers will never need to use LZMA_API_STATIC.
184  *
185  * The GCC variants are a special case on Windows (Cygwin and MinGW).
186  * We rely on GCC doing the right thing with its auto-import feature,
187  * and thus don't use __declspec(dllimport). This way developers don't
188  * need to worry about LZMA_API_STATIC. Also the calling convention is
189  * omitted on Cygwin but not on MinGW.
190  */
191 #ifndef LZMA_API_IMPORT
192 #	if !defined(LZMA_API_STATIC) && defined(_WIN32) && !defined(__GNUC__)
193 #		define LZMA_API_IMPORT __declspec(dllimport)
194 #	else
195 #		define LZMA_API_IMPORT
196 #	endif
197 #endif
198 
199 #ifndef LZMA_API_CALL
200 #	if defined(_WIN32) && !defined(__CYGWIN__)
201 #		define LZMA_API_CALL __cdecl
202 #	else
203 #		define LZMA_API_CALL
204 #	endif
205 #endif
206 
207 #ifndef LZMA_API
208 #	define LZMA_API(type) LZMA_API_IMPORT type LZMA_API_CALL
209 #endif
210 
211 
212 /***********
213  * nothrow *
214  ***********/
215 
216 /*
217  * None of the functions in liblzma may throw an exception. Even
218  * the functions that use callback functions won't throw exceptions,
219  * because liblzma would break if a callback function threw an exception.
220  */
221 #ifndef lzma_nothrow
222 #	if defined(__cplusplus)
223 #		if __cplusplus >= 201103L || (defined(_MSVC_LANG) \
224 				&& _MSVC_LANG >= 201103L)
225 #			define lzma_nothrow noexcept
226 #		else
227 #			define lzma_nothrow throw()
228 #		endif
229 #	elif defined(__GNUC__) && (__GNUC__ > 3 \
230 			|| (__GNUC__ == 3 && __GNUC_MINOR__ >= 3))
231 #		define lzma_nothrow __attribute__((__nothrow__))
232 #	else
233 #		define lzma_nothrow
234 #	endif
235 #endif
236 
237 
238 /********************
239  * GNU C extensions *
240  ********************/
241 
242 /*
243  * GNU C extensions are used conditionally in the public API. It doesn't
244  * break anything if these are sometimes enabled and sometimes not, only
245  * affects warnings and optimizations.
246  */
247 #if defined(__GNUC__) && __GNUC__ >= 3
248 #	ifndef lzma_attribute
249 #		define lzma_attribute(attr) __attribute__(attr)
250 #	endif
251 
252 	/* warn_unused_result was added in GCC 3.4. */
253 #	ifndef lzma_attr_warn_unused_result
254 #		if __GNUC__ == 3 && __GNUC_MINOR__ < 4
255 #			define lzma_attr_warn_unused_result
256 #		endif
257 #	endif
258 
259 #else
260 #	ifndef lzma_attribute
261 #		define lzma_attribute(attr)
262 #	endif
263 #endif
264 
265 
266 #ifndef lzma_attr_pure
267 #	define lzma_attr_pure lzma_attribute((__pure__))
268 #endif
269 
270 #ifndef lzma_attr_const
271 #	define lzma_attr_const lzma_attribute((__const__))
272 #endif
273 
274 #ifndef lzma_attr_warn_unused_result
275 #	define lzma_attr_warn_unused_result \
276 		lzma_attribute((__warn_unused_result__))
277 #endif
278 
279 
280 /**************
281  * Subheaders *
282  **************/
283 
284 #ifdef __cplusplus
285 extern "C" {
286 #endif
287 
288 /*
289  * Subheaders check that this is defined. It is to prevent including
290  * them directly from applications.
291  */
292 #define LZMA_H_INTERNAL 1
293 
294 /* Basic features */
295 #include "lzma/version.h"
296 #include "lzma/base.h"
297 #include "lzma/vli.h"
298 #include "lzma/check.h"
299 
300 /* Filters */
301 #include "lzma/filter.h"
302 #include "lzma/bcj.h"
303 #include "lzma/delta.h"
304 #include "lzma/lzma12.h"
305 
306 /* Container formats */
307 #include "lzma/container.h"
308 
309 /* Advanced features */
310 #include "lzma/stream_flags.h"
311 #include "lzma/block.h"
312 #include "lzma/index.h"
313 #include "lzma/index_hash.h"
314 
315 /* Hardware information */
316 #include "lzma/hardware.h"
317 
318 /*
319  * All subheaders included. Undefine LZMA_H_INTERNAL to prevent applications
320  * re-including the subheaders.
321  */
322 #undef LZMA_H_INTERNAL
323 
324 #ifdef __cplusplus
325 }
326 #endif
327 
328 #endif /* ifndef LZMA_H */
329