xref: /freebsd/contrib/xz/src/liblzma/api/lzma/block.h (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /**
2  * \file        lzma/block.h
3  * \brief       .xz Block handling
4  * \note        Never include this file directly. Use <lzma.h> instead.
5  */
6 
7 /*
8  * Author: Lasse Collin
9  *
10  * This file has been put into the public domain.
11  * You can do whatever you want with this file.
12  */
13 
14 #ifndef LZMA_H_INTERNAL
15 #	error Never include this file directly. Use <lzma.h> instead.
16 #endif
17 
18 
19 /**
20  * \brief       Options for the Block and Block Header encoders and decoders
21  *
22  * Different Block handling functions use different parts of this structure.
23  * Some read some members, other functions write, and some do both. Only the
24  * members listed for reading need to be initialized when the specified
25  * functions are called. The members marked for writing will be assigned
26  * new values at some point either by calling the given function or by
27  * later calls to lzma_code().
28  */
29 typedef struct {
30 	/**
31 	 * \brief       Block format version
32 	 *
33 	 * To prevent API and ABI breakages when new features are needed,
34 	 * a version number is used to indicate which members in this
35 	 * structure are in use:
36 	 *   - liblzma >= 5.0.0: version = 0 is supported.
37 	 *   - liblzma >= 5.1.4beta: Support for version = 1 was added,
38 	 *     which adds the ignore_check member.
39 	 *
40 	 * If version is greater than one, most Block related functions
41 	 * will return LZMA_OPTIONS_ERROR (lzma_block_header_decode() works
42 	 * with any version value).
43 	 *
44 	 * Read by:
45 	 *  - lzma_block_header_size()
46 	 *  - lzma_block_header_encode()
47 	 *  - lzma_block_header_decode()
48 	 *  - lzma_block_compressed_size()
49 	 *  - lzma_block_unpadded_size()
50 	 *  - lzma_block_total_size()
51 	 *  - lzma_block_encoder()
52 	 *  - lzma_block_decoder()
53 	 *  - lzma_block_buffer_encode()
54 	 *  - lzma_block_uncomp_encode()
55 	 *  - lzma_block_buffer_decode()
56 	 *
57 	 * Written by:
58 	 *  - lzma_block_header_decode()
59 	 */
60 	uint32_t version;
61 
62 	/**
63 	 * \brief       Size of the Block Header field in bytes
64 	 *
65 	 * This is always a multiple of four.
66 	 *
67 	 * Read by:
68 	 *  - lzma_block_header_encode()
69 	 *  - lzma_block_header_decode()
70 	 *  - lzma_block_compressed_size()
71 	 *  - lzma_block_unpadded_size()
72 	 *  - lzma_block_total_size()
73 	 *  - lzma_block_decoder()
74 	 *  - lzma_block_buffer_decode()
75 	 *
76 	 * Written by:
77 	 *  - lzma_block_header_size()
78 	 *  - lzma_block_buffer_encode()
79 	 *  - lzma_block_uncomp_encode()
80 	 */
81 	uint32_t header_size;
82 #	define LZMA_BLOCK_HEADER_SIZE_MIN 8
83 #	define LZMA_BLOCK_HEADER_SIZE_MAX 1024
84 
85 	/**
86 	 * \brief       Type of integrity Check
87 	 *
88 	 * The Check ID is not stored into the Block Header, thus its value
89 	 * must be provided also when decoding.
90 	 *
91 	 * Read by:
92 	 *  - lzma_block_header_encode()
93 	 *  - lzma_block_header_decode()
94 	 *  - lzma_block_compressed_size()
95 	 *  - lzma_block_unpadded_size()
96 	 *  - lzma_block_total_size()
97 	 *  - lzma_block_encoder()
98 	 *  - lzma_block_decoder()
99 	 *  - lzma_block_buffer_encode()
100 	 *  - lzma_block_buffer_decode()
101 	 */
102 	lzma_check check;
103 
104 	/**
105 	 * \brief       Size of the Compressed Data in bytes
106 	 *
107 	 * Encoding: If this is not LZMA_VLI_UNKNOWN, Block Header encoder
108 	 * will store this value to the Block Header. Block encoder doesn't
109 	 * care about this value, but will set it once the encoding has been
110 	 * finished.
111 	 *
112 	 * Decoding: If this is not LZMA_VLI_UNKNOWN, Block decoder will
113 	 * verify that the size of the Compressed Data field matches
114 	 * compressed_size.
115 	 *
116 	 * Usually you don't know this value when encoding in streamed mode,
117 	 * and thus cannot write this field into the Block Header.
118 	 *
119 	 * In non-streamed mode you can reserve space for this field before
120 	 * encoding the actual Block. After encoding the data, finish the
121 	 * Block by encoding the Block Header. Steps in detail:
122 	 *
123 	 *  - Set compressed_size to some big enough value. If you don't know
124 	 *    better, use LZMA_VLI_MAX, but remember that bigger values take
125 	 *    more space in Block Header.
126 	 *
127 	 *  - Call lzma_block_header_size() to see how much space you need to
128 	 *    reserve for the Block Header.
129 	 *
130 	 *  - Encode the Block using lzma_block_encoder() and lzma_code().
131 	 *    It sets compressed_size to the correct value.
132 	 *
133 	 *  - Use lzma_block_header_encode() to encode the Block Header.
134 	 *    Because space was reserved in the first step, you don't need
135 	 *    to call lzma_block_header_size() anymore, because due to
136 	 *    reserving, header_size has to be big enough. If it is "too big",
137 	 *    lzma_block_header_encode() will add enough Header Padding to
138 	 *    make Block Header to match the size specified by header_size.
139 	 *
140 	 * Read by:
141 	 *  - lzma_block_header_size()
142 	 *  - lzma_block_header_encode()
143 	 *  - lzma_block_compressed_size()
144 	 *  - lzma_block_unpadded_size()
145 	 *  - lzma_block_total_size()
146 	 *  - lzma_block_decoder()
147 	 *  - lzma_block_buffer_decode()
148 	 *
149 	 * Written by:
150 	 *  - lzma_block_header_decode()
151 	 *  - lzma_block_compressed_size()
152 	 *  - lzma_block_encoder()
153 	 *  - lzma_block_decoder()
154 	 *  - lzma_block_buffer_encode()
155 	 *  - lzma_block_uncomp_encode()
156 	 *  - lzma_block_buffer_decode()
157 	 */
158 	lzma_vli compressed_size;
159 
160 	/**
161 	 * \brief       Uncompressed Size in bytes
162 	 *
163 	 * This is handled very similarly to compressed_size above.
164 	 *
165 	 * uncompressed_size is needed by fewer functions than
166 	 * compressed_size. This is because uncompressed_size isn't
167 	 * needed to validate that Block stays within proper limits.
168 	 *
169 	 * Read by:
170 	 *  - lzma_block_header_size()
171 	 *  - lzma_block_header_encode()
172 	 *  - lzma_block_decoder()
173 	 *  - lzma_block_buffer_decode()
174 	 *
175 	 * Written by:
176 	 *  - lzma_block_header_decode()
177 	 *  - lzma_block_encoder()
178 	 *  - lzma_block_decoder()
179 	 *  - lzma_block_buffer_encode()
180 	 *  - lzma_block_uncomp_encode()
181 	 *  - lzma_block_buffer_decode()
182 	 */
183 	lzma_vli uncompressed_size;
184 
185 	/**
186 	 * \brief       Array of filters
187 	 *
188 	 * There can be 1-4 filters. The end of the array is marked with
189 	 * .id = LZMA_VLI_UNKNOWN.
190 	 *
191 	 * Read by:
192 	 *  - lzma_block_header_size()
193 	 *  - lzma_block_header_encode()
194 	 *  - lzma_block_encoder()
195 	 *  - lzma_block_decoder()
196 	 *  - lzma_block_buffer_encode()
197 	 *  - lzma_block_buffer_decode()
198 	 *
199 	 * Written by:
200 	 *  - lzma_block_header_decode(): Note that this does NOT free()
201 	 *    the old filter options structures. All unused filters[] will
202 	 *    have .id == LZMA_VLI_UNKNOWN and .options == NULL. If
203 	 *    decoding fails, all filters[] are guaranteed to be
204 	 *    LZMA_VLI_UNKNOWN and NULL.
205 	 *
206 	 * \note        Because of the array is terminated with
207 	 *              .id = LZMA_VLI_UNKNOWN, the actual array must
208 	 *              have LZMA_FILTERS_MAX + 1 members or the Block
209 	 *              Header decoder will overflow the buffer.
210 	 */
211 	lzma_filter *filters;
212 
213 	/**
214 	 * \brief       Raw value stored in the Check field
215 	 *
216 	 * After successful coding, the first lzma_check_size(check) bytes
217 	 * of this array contain the raw value stored in the Check field.
218 	 *
219 	 * Note that CRC32 and CRC64 are stored in little endian byte order.
220 	 * Take it into account if you display the Check values to the user.
221 	 *
222 	 * Written by:
223 	 *  - lzma_block_encoder()
224 	 *  - lzma_block_decoder()
225 	 *  - lzma_block_buffer_encode()
226 	 *  - lzma_block_uncomp_encode()
227 	 *  - lzma_block_buffer_decode()
228 	 */
229 	uint8_t raw_check[LZMA_CHECK_SIZE_MAX];
230 
231 	/*
232 	 * Reserved space to allow possible future extensions without
233 	 * breaking the ABI. You should not touch these, because the names
234 	 * of these variables may change. These are and will never be used
235 	 * with the currently supported options, so it is safe to leave these
236 	 * uninitialized.
237 	 */
238 
239 	/** \private     Reserved member. */
240 	void *reserved_ptr1;
241 
242 	/** \private     Reserved member. */
243 	void *reserved_ptr2;
244 
245 	/** \private     Reserved member. */
246 	void *reserved_ptr3;
247 
248 	/** \private     Reserved member. */
249 	uint32_t reserved_int1;
250 
251 	/** \private     Reserved member. */
252 	uint32_t reserved_int2;
253 
254 	/** \private     Reserved member. */
255 	lzma_vli reserved_int3;
256 
257 	/** \private     Reserved member. */
258 	lzma_vli reserved_int4;
259 
260 	/** \private     Reserved member. */
261 	lzma_vli reserved_int5;
262 
263 	/** \private     Reserved member. */
264 	lzma_vli reserved_int6;
265 
266 	/** \private     Reserved member. */
267 	lzma_vli reserved_int7;
268 
269 	/** \private     Reserved member. */
270 	lzma_vli reserved_int8;
271 
272 	/** \private     Reserved member. */
273 	lzma_reserved_enum reserved_enum1;
274 
275 	/** \private     Reserved member. */
276 	lzma_reserved_enum reserved_enum2;
277 
278 	/** \private     Reserved member. */
279 	lzma_reserved_enum reserved_enum3;
280 
281 	/** \private     Reserved member. */
282 	lzma_reserved_enum reserved_enum4;
283 
284 	/**
285 	 * \brief       A flag to Block decoder to not verify the Check field
286 	 *
287 	 * This member is supported by liblzma >= 5.1.4beta if .version >= 1.
288 	 *
289 	 * If this is set to true, the integrity check won't be calculated
290 	 * and verified. Unless you know what you are doing, you should
291 	 * leave this to false. (A reason to set this to true is when the
292 	 * file integrity is verified externally anyway and you want to
293 	 * speed up the decompression, which matters mostly when using
294 	 * SHA-256 as the integrity check.)
295 	 *
296 	 * If .version >= 1, read by:
297 	 *   - lzma_block_decoder()
298 	 *   - lzma_block_buffer_decode()
299 	 *
300 	 * Written by (.version is ignored):
301 	 *   - lzma_block_header_decode() always sets this to false
302 	 */
303 	lzma_bool ignore_check;
304 
305 	/** \private     Reserved member. */
306 	lzma_bool reserved_bool2;
307 
308 	/** \private     Reserved member. */
309 	lzma_bool reserved_bool3;
310 
311 	/** \private     Reserved member. */
312 	lzma_bool reserved_bool4;
313 
314 	/** \private     Reserved member. */
315 	lzma_bool reserved_bool5;
316 
317 	/** \private     Reserved member. */
318 	lzma_bool reserved_bool6;
319 
320 	/** \private     Reserved member. */
321 	lzma_bool reserved_bool7;
322 
323 	/** \private     Reserved member. */
324 	lzma_bool reserved_bool8;
325 
326 } lzma_block;
327 
328 
329 /**
330  * \brief       Decode the Block Header Size field
331  *
332  * To decode Block Header using lzma_block_header_decode(), the size of the
333  * Block Header has to be known and stored into lzma_block.header_size.
334  * The size can be calculated from the first byte of a Block using this macro.
335  * Note that if the first byte is 0x00, it indicates beginning of Index; use
336  * this macro only when the byte is not 0x00.
337  *
338  * There is no encoding macro because lzma_block_header_size() and
339  * lzma_block_header_encode() should be used.
340  */
341 #define lzma_block_header_size_decode(b) (((uint32_t)(b) + 1) * 4)
342 
343 
344 /**
345  * \brief       Calculate Block Header Size
346  *
347  * Calculate the minimum size needed for the Block Header field using the
348  * settings specified in the lzma_block structure. Note that it is OK to
349  * increase the calculated header_size value as long as it is a multiple of
350  * four and doesn't exceed LZMA_BLOCK_HEADER_SIZE_MAX. Increasing header_size
351  * just means that lzma_block_header_encode() will add Header Padding.
352  *
353  * \note        This doesn't check that all the options are valid i.e. this
354  *              may return LZMA_OK even if lzma_block_header_encode() or
355  *              lzma_block_encoder() would fail. If you want to validate the
356  *              filter chain, consider using lzma_memlimit_encoder() which as
357  *              a side-effect validates the filter chain.
358  *
359  * \param       block   Block options
360  *
361  * \return      Possible lzma_ret values:
362  *              - LZMA_OK: Size calculated successfully and stored to
363  *                block->header_size.
364  *              - LZMA_OPTIONS_ERROR: Unsupported version, filters or
365  *                filter options.
366  *              - LZMA_PROG_ERROR: Invalid values like compressed_size == 0.
367  */
368 extern LZMA_API(lzma_ret) lzma_block_header_size(lzma_block *block)
369 		lzma_nothrow lzma_attr_warn_unused_result;
370 
371 
372 /**
373  * \brief       Encode Block Header
374  *
375  * The caller must have calculated the size of the Block Header already with
376  * lzma_block_header_size(). If a value larger than the one calculated by
377  * lzma_block_header_size() is used, the Block Header will be padded to the
378  * specified size.
379  *
380  * \param       block       Block options to be encoded.
381  * \param[out]  out         Beginning of the output buffer. This must be
382  *                          at least block->header_size bytes.
383  *
384  * \return      Possible lzma_ret values:
385  *              - LZMA_OK: Encoding was successful. block->header_size
386  *                bytes were written to output buffer.
387  *              - LZMA_OPTIONS_ERROR: Invalid or unsupported options.
388  *              - LZMA_PROG_ERROR: Invalid arguments, for example
389  *                block->header_size is invalid or block->filters is NULL.
390  */
391 extern LZMA_API(lzma_ret) lzma_block_header_encode(
392 		const lzma_block *block, uint8_t *out)
393 		lzma_nothrow lzma_attr_warn_unused_result;
394 
395 
396 /**
397  * \brief       Decode Block Header
398  *
399  * block->version should (usually) be set to the highest value supported
400  * by the application. If the application sets block->version to a value
401  * higher than supported by the current liblzma version, this function will
402  * downgrade block->version to the highest value supported by it. Thus one
403  * should check the value of block->version after calling this function if
404  * block->version was set to a non-zero value and the application doesn't
405  * otherwise know that the liblzma version being used is new enough to
406  * support the specified block->version.
407  *
408  * The size of the Block Header must have already been decoded with
409  * lzma_block_header_size_decode() macro and stored to block->header_size.
410  *
411  * The integrity check type from Stream Header must have been stored
412  * to block->check.
413  *
414  * block->filters must have been allocated, but they don't need to be
415  * initialized (possible existing filter options are not freed).
416  *
417  * \param[out]  block       Destination for Block options
418  * \param       allocator   lzma_allocator for custom allocator functions.
419  *                          Set to NULL to use malloc() (and also free()
420  *                          if an error occurs).
421  * \param       in          Beginning of the input buffer. This must be
422  *                          at least block->header_size bytes.
423  *
424  * \return      Possible lzma_ret values:
425  *              - LZMA_OK: Decoding was successful. block->header_size
426  *                bytes were read from the input buffer.
427  *              - LZMA_OPTIONS_ERROR: The Block Header specifies some
428  *                unsupported options such as unsupported filters. This can
429  *                happen also if block->version was set to a too low value
430  *                compared to what would be required to properly represent
431  *                the information stored in the Block Header.
432  *              - LZMA_DATA_ERROR: Block Header is corrupt, for example,
433  *                the CRC32 doesn't match.
434  *              - LZMA_PROG_ERROR: Invalid arguments, for example
435  *                block->header_size is invalid or block->filters is NULL.
436  */
437 extern LZMA_API(lzma_ret) lzma_block_header_decode(lzma_block *block,
438 		const lzma_allocator *allocator, const uint8_t *in)
439 		lzma_nothrow lzma_attr_warn_unused_result;
440 
441 
442 /**
443  * \brief       Validate and set Compressed Size according to Unpadded Size
444  *
445  * Block Header stores Compressed Size, but Index has Unpadded Size. If the
446  * application has already parsed the Index and is now decoding Blocks,
447  * it can calculate Compressed Size from Unpadded Size. This function does
448  * exactly that with error checking:
449  *
450  *  - Compressed Size calculated from Unpadded Size must be positive integer,
451  *    that is, Unpadded Size must be big enough that after Block Header and
452  *    Check fields there's still at least one byte for Compressed Size.
453  *
454  *  - If Compressed Size was present in Block Header, the new value
455  *    calculated from Unpadded Size is compared against the value
456  *    from Block Header.
457  *
458  * \note        This function must be called _after_ decoding the Block Header
459  *              field so that it can properly validate Compressed Size if it
460  *              was present in Block Header.
461  *
462  * \param       block           Block options: block->header_size must
463  *                              already be set with lzma_block_header_size().
464  * \param       unpadded_size   Unpadded Size from the Index field in bytes
465  *
466  * \return      Possible lzma_ret values:
467  *              - LZMA_OK: block->compressed_size was set successfully.
468  *              - LZMA_DATA_ERROR: unpadded_size is too small compared to
469  *                block->header_size and lzma_check_size(block->check).
470  *              - LZMA_PROG_ERROR: Some values are invalid. For example,
471  *                block->header_size must be a multiple of four and
472  *                between 8 and 1024 inclusive.
473  */
474 extern LZMA_API(lzma_ret) lzma_block_compressed_size(
475 		lzma_block *block, lzma_vli unpadded_size)
476 		lzma_nothrow lzma_attr_warn_unused_result;
477 
478 
479 /**
480  * \brief       Calculate Unpadded Size
481  *
482  * The Index field stores Unpadded Size and Uncompressed Size. The latter
483  * can be taken directly from the lzma_block structure after coding a Block,
484  * but Unpadded Size needs to be calculated from Block Header Size,
485  * Compressed Size, and size of the Check field. This is where this function
486  * is needed.
487  *
488  * \param       block   Block options: block->header_size must already be
489  *                      set with lzma_block_header_size().
490  *
491  * \return      Unpadded Size on success, or zero on error.
492  */
493 extern LZMA_API(lzma_vli) lzma_block_unpadded_size(const lzma_block *block)
494 		lzma_nothrow lzma_attr_pure;
495 
496 
497 /**
498  * \brief       Calculate the total encoded size of a Block
499  *
500  * This is equivalent to lzma_block_unpadded_size() except that the returned
501  * value includes the size of the Block Padding field.
502  *
503  * \param       block   Block options: block->header_size must already be
504  *                      set with lzma_block_header_size().
505  *
506  * \return      On success, total encoded size of the Block. On error,
507  *              zero is returned.
508  */
509 extern LZMA_API(lzma_vli) lzma_block_total_size(const lzma_block *block)
510 		lzma_nothrow lzma_attr_pure;
511 
512 
513 /**
514  * \brief       Initialize .xz Block encoder
515  *
516  * Valid actions for lzma_code() are LZMA_RUN, LZMA_SYNC_FLUSH (only if the
517  * filter chain supports it), and LZMA_FINISH.
518  *
519  * The Block encoder encodes the Block Data, Block Padding, and Check value.
520  * It does NOT encode the Block Header which can be encoded with
521  * lzma_block_header_encode().
522  *
523  * \param       strm    Pointer to lzma_stream that is at least initialized
524  *                      with LZMA_STREAM_INIT.
525  * \param       block   Block options: block->version, block->check,
526  *                      and block->filters must have been initialized.
527  *
528  * \return      Possible lzma_ret values:
529  *              - LZMA_OK: All good, continue with lzma_code().
530  *              - LZMA_MEM_ERROR
531  *              - LZMA_OPTIONS_ERROR
532  *              - LZMA_UNSUPPORTED_CHECK: block->check specifies a Check ID
533  *                that is not supported by this build of liblzma. Initializing
534  *                the encoder failed.
535  *              - LZMA_PROG_ERROR
536  */
537 extern LZMA_API(lzma_ret) lzma_block_encoder(
538 		lzma_stream *strm, lzma_block *block)
539 		lzma_nothrow lzma_attr_warn_unused_result;
540 
541 
542 /**
543  * \brief       Initialize .xz Block decoder
544  *
545  * Valid actions for lzma_code() are LZMA_RUN and LZMA_FINISH. Using
546  * LZMA_FINISH is not required. It is supported only for convenience.
547  *
548  * The Block decoder decodes the Block Data, Block Padding, and Check value.
549  * It does NOT decode the Block Header which can be decoded with
550  * lzma_block_header_decode().
551  *
552  * \param       strm    Pointer to lzma_stream that is at least initialized
553  *                      with LZMA_STREAM_INIT.
554  * \param       block   Block options
555  *
556  * \return      Possible lzma_ret values:
557  *              - LZMA_OK: All good, continue with lzma_code().
558  *              - LZMA_PROG_ERROR
559  *              - LZMA_MEM_ERROR
560  */
561 extern LZMA_API(lzma_ret) lzma_block_decoder(
562 		lzma_stream *strm, lzma_block *block)
563 		lzma_nothrow lzma_attr_warn_unused_result;
564 
565 
566 /**
567  * \brief       Calculate maximum output size for single-call Block encoding
568  *
569  * This is equivalent to lzma_stream_buffer_bound() but for .xz Blocks.
570  * See the documentation of lzma_stream_buffer_bound().
571  *
572  * \param       uncompressed_size   Size of the data to be encoded with the
573  *                                  single-call Block encoder.
574  *
575  * \return      Maximum output size in bytes for single-call Block encoding.
576  */
577 extern LZMA_API(size_t) lzma_block_buffer_bound(size_t uncompressed_size)
578 		lzma_nothrow;
579 
580 
581 /**
582  * \brief       Single-call .xz Block encoder
583  *
584  * In contrast to the multi-call encoder initialized with
585  * lzma_block_encoder(), this function encodes also the Block Header. This
586  * is required to make it possible to write appropriate Block Header also
587  * in case the data isn't compressible, and different filter chain has to be
588  * used to encode the data in uncompressed form using uncompressed chunks
589  * of the LZMA2 filter.
590  *
591  * When the data isn't compressible, header_size, compressed_size, and
592  * uncompressed_size are set just like when the data was compressible, but
593  * it is possible that header_size is too small to hold the filter chain
594  * specified in block->filters, because that isn't necessarily the filter
595  * chain that was actually used to encode the data. lzma_block_unpadded_size()
596  * still works normally, because it doesn't read the filters array.
597  *
598  * \param       block       Block options: block->version, block->check,
599  *                          and block->filters must have been initialized.
600  * \param       allocator   lzma_allocator for custom allocator functions.
601  *                          Set to NULL to use malloc() and free().
602  * \param       in          Beginning of the input buffer
603  * \param       in_size     Size of the input buffer
604  * \param[out]  out         Beginning of the output buffer
605  * \param[out]  out_pos     The next byte will be written to out[*out_pos].
606  *                          *out_pos is updated only if encoding succeeds.
607  * \param       out_size    Size of the out buffer; the first byte into
608  *                          which no data is written to is out[out_size].
609  *
610  * \return      Possible lzma_ret values:
611  *              - LZMA_OK: Encoding was successful.
612  *              - LZMA_BUF_ERROR: Not enough output buffer space.
613  *              - LZMA_UNSUPPORTED_CHECK
614  *              - LZMA_OPTIONS_ERROR
615  *              - LZMA_MEM_ERROR
616  *              - LZMA_DATA_ERROR
617  *              - LZMA_PROG_ERROR
618  */
619 extern LZMA_API(lzma_ret) lzma_block_buffer_encode(
620 		lzma_block *block, const lzma_allocator *allocator,
621 		const uint8_t *in, size_t in_size,
622 		uint8_t *out, size_t *out_pos, size_t out_size)
623 		lzma_nothrow lzma_attr_warn_unused_result;
624 
625 
626 /**
627  * \brief       Single-call uncompressed .xz Block encoder
628  *
629  * This is like lzma_block_buffer_encode() except this doesn't try to
630  * compress the data and instead encodes the data using LZMA2 uncompressed
631  * chunks. The required output buffer size can be determined with
632  * lzma_block_buffer_bound().
633  *
634  * Since the data won't be compressed, this function ignores block->filters.
635  * This function doesn't take lzma_allocator because this function doesn't
636  * allocate any memory from the heap.
637  *
638  * \param       block       Block options: block->version, block->check,
639  *                          and block->filters must have been initialized.
640  * \param       in          Beginning of the input buffer
641  * \param       in_size     Size of the input buffer
642  * \param[out]  out         Beginning of the output buffer
643  * \param[out]  out_pos     The next byte will be written to out[*out_pos].
644  *                          *out_pos is updated only if encoding succeeds.
645  * \param       out_size    Size of the out buffer; the first byte into
646  *                          which no data is written to is out[out_size].
647  *
648  * \return      Possible lzma_ret values:
649  *              - LZMA_OK: Encoding was successful.
650  *              - LZMA_BUF_ERROR: Not enough output buffer space.
651  *              - LZMA_UNSUPPORTED_CHECK
652  *              - LZMA_OPTIONS_ERROR
653  *              - LZMA_MEM_ERROR
654  *              - LZMA_DATA_ERROR
655  *              - LZMA_PROG_ERROR
656  */
657 extern LZMA_API(lzma_ret) lzma_block_uncomp_encode(lzma_block *block,
658 		const uint8_t *in, size_t in_size,
659 		uint8_t *out, size_t *out_pos, size_t out_size)
660 		lzma_nothrow lzma_attr_warn_unused_result;
661 
662 
663 /**
664  * \brief       Single-call .xz Block decoder
665  *
666  * This is single-call equivalent of lzma_block_decoder(), and requires that
667  * the caller has already decoded Block Header and checked its memory usage.
668  *
669  * \param       block       Block options
670  * \param       allocator   lzma_allocator for custom allocator functions.
671  *                          Set to NULL to use malloc() and free().
672  * \param       in          Beginning of the input buffer
673  * \param       in_pos      The next byte will be read from in[*in_pos].
674  *                          *in_pos is updated only if decoding succeeds.
675  * \param       in_size     Size of the input buffer; the first byte that
676  *                          won't be read is in[in_size].
677  * \param[out]  out         Beginning of the output buffer
678  * \param[out]  out_pos     The next byte will be written to out[*out_pos].
679  *                          *out_pos is updated only if encoding succeeds.
680  * \param       out_size    Size of the out buffer; the first byte into
681  *                          which no data is written to is out[out_size].
682  *
683  * \return      Possible lzma_ret values:
684  *              - LZMA_OK: Decoding was successful.
685  *              - LZMA_OPTIONS_ERROR
686  *              - LZMA_DATA_ERROR
687  *              - LZMA_MEM_ERROR
688  *              - LZMA_BUF_ERROR: Output buffer was too small.
689  *              - LZMA_PROG_ERROR
690  */
691 extern LZMA_API(lzma_ret) lzma_block_buffer_decode(
692 		lzma_block *block, const lzma_allocator *allocator,
693 		const uint8_t *in, size_t *in_pos, size_t in_size,
694 		uint8_t *out, size_t *out_pos, size_t out_size)
695 		lzma_nothrow;
696