liblzma: Improve documentation in index.h
[xz/debian.git] / src / liblzma / common / common.c
bloba708fdf187a6eb16e3c99be0da30e0219ff77c01
1 ///////////////////////////////////////////////////////////////////////////////
2 //
3 /// \file common.c
4 /// \brief Common functions needed in many places in liblzma
5 //
6 // Author: Lasse Collin
7 //
8 // This file has been put into the public domain.
9 // You can do whatever you want with this file.
11 ///////////////////////////////////////////////////////////////////////////////
13 #include "common.h"
16 /////////////
17 // Version //
18 /////////////
20 extern LZMA_API(uint32_t)
21 lzma_version_number(void)
23 return LZMA_VERSION;
27 extern LZMA_API(const char *)
28 lzma_version_string(void)
30 return LZMA_VERSION_STRING;
34 ///////////////////////
35 // Memory allocation //
36 ///////////////////////
38 extern void * lzma_attribute((__malloc__)) lzma_attr_alloc_size(1)
39 lzma_alloc(size_t size, const lzma_allocator *allocator)
41 // Some malloc() variants return NULL if called with size == 0.
42 if (size == 0)
43 size = 1;
45 void *ptr;
47 if (allocator != NULL && allocator->alloc != NULL)
48 ptr = allocator->alloc(allocator->opaque, 1, size);
49 else
50 ptr = malloc(size);
52 return ptr;
56 extern void * lzma_attribute((__malloc__)) lzma_attr_alloc_size(1)
57 lzma_alloc_zero(size_t size, const lzma_allocator *allocator)
59 // Some calloc() variants return NULL if called with size == 0.
60 if (size == 0)
61 size = 1;
63 void *ptr;
65 if (allocator != NULL && allocator->alloc != NULL) {
66 ptr = allocator->alloc(allocator->opaque, 1, size);
67 if (ptr != NULL)
68 memzero(ptr, size);
69 } else {
70 ptr = calloc(1, size);
73 return ptr;
77 extern void
78 lzma_free(void *ptr, const lzma_allocator *allocator)
80 if (allocator != NULL && allocator->free != NULL)
81 allocator->free(allocator->opaque, ptr);
82 else
83 free(ptr);
85 return;
89 //////////
90 // Misc //
91 //////////
93 extern size_t
94 lzma_bufcpy(const uint8_t *restrict in, size_t *restrict in_pos,
95 size_t in_size, uint8_t *restrict out,
96 size_t *restrict out_pos, size_t out_size)
98 const size_t in_avail = in_size - *in_pos;
99 const size_t out_avail = out_size - *out_pos;
100 const size_t copy_size = my_min(in_avail, out_avail);
102 // Call memcpy() only if there is something to copy. If there is
103 // nothing to copy, in or out might be NULL and then the memcpy()
104 // call would trigger undefined behavior.
105 if (copy_size > 0)
106 memcpy(out + *out_pos, in + *in_pos, copy_size);
108 *in_pos += copy_size;
109 *out_pos += copy_size;
111 return copy_size;
115 extern lzma_ret
116 lzma_next_filter_init(lzma_next_coder *next, const lzma_allocator *allocator,
117 const lzma_filter_info *filters)
119 lzma_next_coder_init(filters[0].init, next, allocator);
120 next->id = filters[0].id;
121 return filters[0].init == NULL
122 ? LZMA_OK : filters[0].init(next, allocator, filters);
126 extern lzma_ret
127 lzma_next_filter_update(lzma_next_coder *next, const lzma_allocator *allocator,
128 const lzma_filter *reversed_filters)
130 // Check that the application isn't trying to change the Filter ID.
131 // End of filters is indicated with LZMA_VLI_UNKNOWN in both
132 // reversed_filters[0].id and next->id.
133 if (reversed_filters[0].id != next->id)
134 return LZMA_PROG_ERROR;
136 if (reversed_filters[0].id == LZMA_VLI_UNKNOWN)
137 return LZMA_OK;
139 assert(next->update != NULL);
140 return next->update(next->coder, allocator, NULL, reversed_filters);
144 extern void
145 lzma_next_end(lzma_next_coder *next, const lzma_allocator *allocator)
147 if (next->init != (uintptr_t)(NULL)) {
148 // To avoid tiny end functions that simply call
149 // lzma_free(coder, allocator), we allow leaving next->end
150 // NULL and call lzma_free() here.
151 if (next->end != NULL)
152 next->end(next->coder, allocator);
153 else
154 lzma_free(next->coder, allocator);
156 // Reset the variables so the we don't accidentally think
157 // that it is an already initialized coder.
158 *next = LZMA_NEXT_CODER_INIT;
161 return;
165 //////////////////////////////////////
166 // External to internal API wrapper //
167 //////////////////////////////////////
169 extern lzma_ret
170 lzma_strm_init(lzma_stream *strm)
172 if (strm == NULL)
173 return LZMA_PROG_ERROR;
175 if (strm->internal == NULL) {
176 strm->internal = lzma_alloc(sizeof(lzma_internal),
177 strm->allocator);
178 if (strm->internal == NULL)
179 return LZMA_MEM_ERROR;
181 strm->internal->next = LZMA_NEXT_CODER_INIT;
184 memzero(strm->internal->supported_actions,
185 sizeof(strm->internal->supported_actions));
186 strm->internal->sequence = ISEQ_RUN;
187 strm->internal->allow_buf_error = false;
189 strm->total_in = 0;
190 strm->total_out = 0;
192 return LZMA_OK;
196 extern LZMA_API(lzma_ret)
197 lzma_code(lzma_stream *strm, lzma_action action)
199 // Sanity checks
200 if ((strm->next_in == NULL && strm->avail_in != 0)
201 || (strm->next_out == NULL && strm->avail_out != 0)
202 || strm->internal == NULL
203 || strm->internal->next.code == NULL
204 || (unsigned int)(action) > LZMA_ACTION_MAX
205 || !strm->internal->supported_actions[action])
206 return LZMA_PROG_ERROR;
208 // Check if unsupported members have been set to non-zero or non-NULL,
209 // which would indicate that some new feature is wanted.
210 if (strm->reserved_ptr1 != NULL
211 || strm->reserved_ptr2 != NULL
212 || strm->reserved_ptr3 != NULL
213 || strm->reserved_ptr4 != NULL
214 || strm->reserved_int2 != 0
215 || strm->reserved_int3 != 0
216 || strm->reserved_int4 != 0
217 || strm->reserved_enum1 != LZMA_RESERVED_ENUM
218 || strm->reserved_enum2 != LZMA_RESERVED_ENUM)
219 return LZMA_OPTIONS_ERROR;
221 switch (strm->internal->sequence) {
222 case ISEQ_RUN:
223 switch (action) {
224 case LZMA_RUN:
225 break;
227 case LZMA_SYNC_FLUSH:
228 strm->internal->sequence = ISEQ_SYNC_FLUSH;
229 break;
231 case LZMA_FULL_FLUSH:
232 strm->internal->sequence = ISEQ_FULL_FLUSH;
233 break;
235 case LZMA_FINISH:
236 strm->internal->sequence = ISEQ_FINISH;
237 break;
239 case LZMA_FULL_BARRIER:
240 strm->internal->sequence = ISEQ_FULL_BARRIER;
241 break;
244 break;
246 case ISEQ_SYNC_FLUSH:
247 // The same action must be used until we return
248 // LZMA_STREAM_END, and the amount of input must not change.
249 if (action != LZMA_SYNC_FLUSH
250 || strm->internal->avail_in != strm->avail_in)
251 return LZMA_PROG_ERROR;
253 break;
255 case ISEQ_FULL_FLUSH:
256 if (action != LZMA_FULL_FLUSH
257 || strm->internal->avail_in != strm->avail_in)
258 return LZMA_PROG_ERROR;
260 break;
262 case ISEQ_FINISH:
263 if (action != LZMA_FINISH
264 || strm->internal->avail_in != strm->avail_in)
265 return LZMA_PROG_ERROR;
267 break;
269 case ISEQ_FULL_BARRIER:
270 if (action != LZMA_FULL_BARRIER
271 || strm->internal->avail_in != strm->avail_in)
272 return LZMA_PROG_ERROR;
274 break;
276 case ISEQ_END:
277 return LZMA_STREAM_END;
279 case ISEQ_ERROR:
280 default:
281 return LZMA_PROG_ERROR;
284 size_t in_pos = 0;
285 size_t out_pos = 0;
286 lzma_ret ret = strm->internal->next.code(
287 strm->internal->next.coder, strm->allocator,
288 strm->next_in, &in_pos, strm->avail_in,
289 strm->next_out, &out_pos, strm->avail_out, action);
291 strm->next_in += in_pos;
292 strm->avail_in -= in_pos;
293 strm->total_in += in_pos;
295 strm->next_out += out_pos;
296 strm->avail_out -= out_pos;
297 strm->total_out += out_pos;
299 strm->internal->avail_in = strm->avail_in;
301 switch (ret) {
302 case LZMA_OK:
303 // Don't return LZMA_BUF_ERROR when it happens the first time.
304 // This is to avoid returning LZMA_BUF_ERROR when avail_out
305 // was zero but still there was no more data left to written
306 // to next_out.
307 if (out_pos == 0 && in_pos == 0) {
308 if (strm->internal->allow_buf_error)
309 ret = LZMA_BUF_ERROR;
310 else
311 strm->internal->allow_buf_error = true;
312 } else {
313 strm->internal->allow_buf_error = false;
315 break;
317 case LZMA_TIMED_OUT:
318 strm->internal->allow_buf_error = false;
319 ret = LZMA_OK;
320 break;
322 case LZMA_SEEK_NEEDED:
323 strm->internal->allow_buf_error = false;
325 // If LZMA_FINISH was used, reset it back to the
326 // LZMA_RUN-based state so that new input can be supplied
327 // by the application.
328 if (strm->internal->sequence == ISEQ_FINISH)
329 strm->internal->sequence = ISEQ_RUN;
331 break;
333 case LZMA_STREAM_END:
334 if (strm->internal->sequence == ISEQ_SYNC_FLUSH
335 || strm->internal->sequence == ISEQ_FULL_FLUSH
336 || strm->internal->sequence
337 == ISEQ_FULL_BARRIER)
338 strm->internal->sequence = ISEQ_RUN;
339 else
340 strm->internal->sequence = ISEQ_END;
342 // Fall through
344 case LZMA_NO_CHECK:
345 case LZMA_UNSUPPORTED_CHECK:
346 case LZMA_GET_CHECK:
347 case LZMA_MEMLIMIT_ERROR:
348 // Something else than LZMA_OK, but not a fatal error,
349 // that is, coding may be continued (except if ISEQ_END).
350 strm->internal->allow_buf_error = false;
351 break;
353 default:
354 // All the other errors are fatal; coding cannot be continued.
355 assert(ret != LZMA_BUF_ERROR);
356 strm->internal->sequence = ISEQ_ERROR;
357 break;
360 return ret;
364 extern LZMA_API(void)
365 lzma_end(lzma_stream *strm)
367 if (strm != NULL && strm->internal != NULL) {
368 lzma_next_end(&strm->internal->next, strm->allocator);
369 lzma_free(strm->internal, strm->allocator);
370 strm->internal = NULL;
373 return;
377 #ifdef HAVE_SYMBOL_VERSIONS_LINUX
378 // This is for compatibility with binaries linked against liblzma that
379 // has been patched with xz-5.2.2-compat-libs.patch from RHEL/CentOS 7.
380 LZMA_SYMVER_API("lzma_get_progress@XZ_5.2.2",
381 void, lzma_get_progress_522)(lzma_stream *strm,
382 uint64_t *progress_in, uint64_t *progress_out) lzma_nothrow
383 __attribute__((__alias__("lzma_get_progress_52")));
385 LZMA_SYMVER_API("lzma_get_progress@@XZ_5.2",
386 void, lzma_get_progress_52)(lzma_stream *strm,
387 uint64_t *progress_in, uint64_t *progress_out) lzma_nothrow;
389 #define lzma_get_progress lzma_get_progress_52
390 #endif
391 extern LZMA_API(void)
392 lzma_get_progress(lzma_stream *strm,
393 uint64_t *progress_in, uint64_t *progress_out)
395 if (strm->internal->next.get_progress != NULL) {
396 strm->internal->next.get_progress(strm->internal->next.coder,
397 progress_in, progress_out);
398 } else {
399 *progress_in = strm->total_in;
400 *progress_out = strm->total_out;
403 return;
407 extern LZMA_API(lzma_check)
408 lzma_get_check(const lzma_stream *strm)
410 // Return LZMA_CHECK_NONE if we cannot know the check type.
411 // It's a bug in the application if this happens.
412 if (strm->internal->next.get_check == NULL)
413 return LZMA_CHECK_NONE;
415 return strm->internal->next.get_check(strm->internal->next.coder);
419 extern LZMA_API(uint64_t)
420 lzma_memusage(const lzma_stream *strm)
422 uint64_t memusage;
423 uint64_t old_memlimit;
425 if (strm == NULL || strm->internal == NULL
426 || strm->internal->next.memconfig == NULL
427 || strm->internal->next.memconfig(
428 strm->internal->next.coder,
429 &memusage, &old_memlimit, 0) != LZMA_OK)
430 return 0;
432 return memusage;
436 extern LZMA_API(uint64_t)
437 lzma_memlimit_get(const lzma_stream *strm)
439 uint64_t old_memlimit;
440 uint64_t memusage;
442 if (strm == NULL || strm->internal == NULL
443 || strm->internal->next.memconfig == NULL
444 || strm->internal->next.memconfig(
445 strm->internal->next.coder,
446 &memusage, &old_memlimit, 0) != LZMA_OK)
447 return 0;
449 return old_memlimit;
453 extern LZMA_API(lzma_ret)
454 lzma_memlimit_set(lzma_stream *strm, uint64_t new_memlimit)
456 // Dummy variables to simplify memconfig functions
457 uint64_t old_memlimit;
458 uint64_t memusage;
460 if (strm == NULL || strm->internal == NULL
461 || strm->internal->next.memconfig == NULL)
462 return LZMA_PROG_ERROR;
464 // Zero is a special value that cannot be used as an actual limit.
465 // If 0 was specified, use 1 instead.
466 if (new_memlimit == 0)
467 new_memlimit = 1;
469 return strm->internal->next.memconfig(strm->internal->next.coder,
470 &memusage, &old_memlimit, new_memlimit);