mirror of https://git.tukaani.org/xz.git
liblzma: Update the comments in the API headers.
Adding support for LZMA_FINISH for Index encoding and decoding needed tiny additions to the relevant .c files too.
This commit is contained in:
parent
33c1c0e102
commit
d09c5753e3
|
@ -60,8 +60,8 @@
|
|||
*
|
||||
* Some could argue that liblzma API should provide all the required types,
|
||||
* for example lzma_uint64, LZMA_UINT64_C(n), and LZMA_UINT64_MAX. This was
|
||||
* seen unnecessary mess, since most systems already provide all the necessary
|
||||
* types and macros in the standard headers.
|
||||
* seen as an unnecessary mess, since most systems already provide all the
|
||||
* necessary types and macros in the standard headers.
|
||||
*
|
||||
* Note that liblzma API still has lzma_bool, because using stdbool.h would
|
||||
* break C89 and C++ programs on many systems. sizeof(bool) in C99 isn't
|
||||
|
|
|
@ -281,21 +281,21 @@ typedef enum {
|
|||
* Using LZMA_SYNC_FLUSH very often can dramatically reduce
|
||||
* the compression ratio. With some filters (for example,
|
||||
* LZMA2), fine-tuning the compression options may help
|
||||
* mitigate this problem significantly.
|
||||
* mitigate this problem significantly (for example,
|
||||
* match finder with LZMA2).
|
||||
*
|
||||
* Decoders don't support LZMA_SYNC_FLUSH.
|
||||
*/
|
||||
|
||||
LZMA_FULL_FLUSH = 2,
|
||||
/**<
|
||||
* \brief Make all the input available at output
|
||||
* \brief Finish encoding of the current Block
|
||||
*
|
||||
* Finish encoding of the current Block. All the input
|
||||
* data going to the current Block must have been given
|
||||
* to the encoder (the last bytes can still be pending in
|
||||
* next_in). Call lzma_code() with LZMA_FULL_FLUSH until
|
||||
* it returns LZMA_STREAM_END. Then continue normally with
|
||||
* LZMA_RUN or finish the Stream with LZMA_FINISH.
|
||||
* All the input data going to the current Block must have
|
||||
* been given to the encoder (the last bytes can still be
|
||||
* pending in* next_in). Call lzma_code() with LZMA_FULL_FLUSH
|
||||
* until it returns LZMA_STREAM_END. Then continue normally
|
||||
* with LZMA_RUN or finish the Stream with LZMA_FINISH.
|
||||
*
|
||||
* This action is currently supported only by Stream encoder
|
||||
* and easy encoder (which uses Stream encoder). If there is
|
||||
|
@ -306,12 +306,12 @@ typedef enum {
|
|||
/**<
|
||||
* \brief Finish the coding operation
|
||||
*
|
||||
* Finishes the coding operation. All the input data must
|
||||
* have been given to the encoder (the last bytes can still
|
||||
* be pending in next_in). Call lzma_code() with LZMA_FINISH
|
||||
* until it returns LZMA_STREAM_END. Once LZMA_FINISH has
|
||||
* been used, the amount of input must no longer be changed
|
||||
* by the application.
|
||||
* All the input data must have been given to the encoder
|
||||
* (the last bytes can still be pending in next_in).
|
||||
* Call lzma_code() with LZMA_FINISH until it returns
|
||||
* LZMA_STREAM_END. Once LZMA_FINISH has been used,
|
||||
* the amount of input must no longer be changed by
|
||||
* the application.
|
||||
*
|
||||
* When decoding, using LZMA_FINISH is optional unless the
|
||||
* LZMA_CONCATENATED flag was used when the decoder was
|
||||
|
@ -554,11 +554,11 @@ extern LZMA_API(void) lzma_end(lzma_stream *strm) lzma_nothrow;
|
|||
* this may give misleading information if decoding .xz Streams that have
|
||||
* multiple Blocks, because each Block can have different memory requirements.
|
||||
*
|
||||
* \return Rough estimate of how much memory is currently allocated
|
||||
* for the filter decoders. If no filter chain is currently
|
||||
* allocated, some non-zero value is still returned, which is
|
||||
* less than or equal to what any filter chain would indicate
|
||||
* as its memory requirement.
|
||||
* \return How much memory is currently allocated for the filter
|
||||
* decoders. If no filter chain is currently allocated,
|
||||
* some non-zero value is still returned, which is less than
|
||||
* or equal to what any filter chain would indicate as its
|
||||
* memory requirement.
|
||||
*
|
||||
* If this function isn't supported by *strm or some other error
|
||||
* occurs, zero is returned.
|
||||
|
|
|
@ -31,7 +31,7 @@
|
|||
|
||||
#define LZMA_FILTER_IA64 LZMA_VLI_C(0x06)
|
||||
/**<
|
||||
* Filter for IA64 (Itanium) binaries.
|
||||
* Filter for IA-64 (Itanium) binaries.
|
||||
*/
|
||||
|
||||
#define LZMA_FILTER_ARM LZMA_VLI_C(0x07)
|
||||
|
@ -41,7 +41,7 @@
|
|||
|
||||
#define LZMA_FILTER_ARMTHUMB LZMA_VLI_C(0x08)
|
||||
/**<
|
||||
* Filter for ARMThumb binaries.
|
||||
* Filter for ARM-Thumb binaries.
|
||||
*/
|
||||
|
||||
#define LZMA_FILTER_SPARC LZMA_VLI_C(0x09)
|
||||
|
|
|
@ -318,8 +318,8 @@ extern LZMA_API(lzma_ret) lzma_block_header_encode(
|
|||
* The size of the Block Header must have already been decoded with
|
||||
* lzma_block_header_size_decode() macro and stored to block->header_size.
|
||||
*
|
||||
* block->filters must have been allocated, but not necessarily initialized.
|
||||
* Possible existing filter options are _not_ freed.
|
||||
* block->filters must have been allocated, but they don't need to be
|
||||
* initialized (possible existing filter options are not freed).
|
||||
*
|
||||
* \param block Destination for Block options.
|
||||
* \param allocator lzma_allocator for custom allocator functions.
|
||||
|
|
|
@ -55,13 +55,13 @@
|
|||
*
|
||||
* This flag doesn't affect the memory usage requirements of the decoder (at
|
||||
* least not significantly). The memory usage of the encoder may be increased
|
||||
* a little but only at the lowest preset levels (0-2).
|
||||
* a little but only at the lowest preset levels (0-3).
|
||||
*/
|
||||
#define LZMA_PRESET_EXTREME (UINT32_C(1) << 31)
|
||||
|
||||
|
||||
/**
|
||||
* \brief Calculate rough memory usage of easy encoder
|
||||
* \brief Calculate approximate memory usage of easy encoder
|
||||
*
|
||||
* This function is a wrapper for lzma_raw_encoder_memusage().
|
||||
*
|
||||
|
@ -72,7 +72,7 @@ extern LZMA_API(uint64_t) lzma_easy_encoder_memusage(uint32_t preset)
|
|||
|
||||
|
||||
/**
|
||||
* \brief Calculate rough decoder memory usage of a preset
|
||||
* \brief Calculate approximate decoder memory usage of a preset
|
||||
*
|
||||
* This function is a wrapper for lzma_raw_decoder_memusage().
|
||||
*
|
||||
|
@ -93,16 +93,19 @@ extern LZMA_API(uint64_t) lzma_easy_decoder_memusage(uint32_t preset)
|
|||
* \param preset Compression preset to use. A preset consist of level
|
||||
* number and zero or more flags. Usually flags aren't
|
||||
* used, so preset is simply a number [0, 9] which match
|
||||
* the options -0 .. -9 of the xz command line tool.
|
||||
* the options -0 ... -9 of the xz command line tool.
|
||||
* Additional flags can be be set using bitwise-or with
|
||||
* the preset level number, e.g. 6 | LZMA_PRESET_EXTREME.
|
||||
* \param check Integrity check type to use. See check.h for available
|
||||
* checks. If you are unsure, use LZMA_CHECK_CRC32.
|
||||
* checks. The xz command line tool defaults to
|
||||
* LZMA_CHECK_CRC64, which is a good choice if you are
|
||||
* unsure. LZMA_CHECK_CRC32 is good too as long as the
|
||||
* uncompressed file is not many gigabytes.
|
||||
*
|
||||
* \return - LZMA_OK: Initialization succeeded. Use lzma_code() to
|
||||
* encode your data.
|
||||
* - LZMA_MEM_ERROR: Memory allocation failed.
|
||||
* - LZMA_OPTIONS_ERROR: The given compression level is not
|
||||
* - LZMA_OPTIONS_ERROR: The given compression preset is not
|
||||
* supported by this build of liblzma.
|
||||
* - LZMA_UNSUPPORTED_CHECK: The given check type is not
|
||||
* supported by this liblzma build.
|
||||
|
@ -310,7 +313,8 @@ extern LZMA_API(lzma_ret) lzma_stream_buffer_encode(
|
|||
* \brief Initialize .xz Stream decoder
|
||||
*
|
||||
* \param strm Pointer to properly prepared lzma_stream
|
||||
* \param memlimit Rough memory usage limit as bytes
|
||||
* \param memlimit Memory usage limit as bytes. Use UINT64_MAX
|
||||
* to effectively disable the limiter.
|
||||
* \param flags Bitwise-or of zero or more of the decoder flags:
|
||||
* LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK,
|
||||
* LZMA_TELL_ANY_CHECK, LZMA_CONCATENATED
|
||||
|
@ -318,6 +322,7 @@ extern LZMA_API(lzma_ret) lzma_stream_buffer_encode(
|
|||
* \return - LZMA_OK: Initialization was successful.
|
||||
* - LZMA_MEM_ERROR: Cannot allocate memory.
|
||||
* - LZMA_OPTIONS_ERROR: Unsupported flags
|
||||
* - LZMA_PROG_ERROR
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_stream_decoder(
|
||||
lzma_stream *strm, uint64_t memlimit, uint32_t flags)
|
||||
|
@ -332,12 +337,14 @@ extern LZMA_API(lzma_ret) lzma_stream_decoder(
|
|||
* of the input file has been detected.
|
||||
*
|
||||
* \param strm Pointer to properly prepared lzma_stream
|
||||
* \param memlimit Rough memory usage limit as bytes
|
||||
* \param memlimit Memory usage limit as bytes. Use UINT64_MAX
|
||||
* to effectively disable the limiter.
|
||||
* \param flags Bitwise-or of flags, or zero for no flags.
|
||||
*
|
||||
* \return - LZMA_OK: Initialization was successful.
|
||||
* - LZMA_MEM_ERROR: Cannot allocate memory.
|
||||
* - LZMA_OPTIONS_ERROR: Unsupported flags
|
||||
* - LZMA_PROG_ERROR
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_auto_decoder(
|
||||
lzma_stream *strm, uint64_t memlimit, uint32_t flags)
|
||||
|
@ -353,6 +360,7 @@ extern LZMA_API(lzma_ret) lzma_auto_decoder(
|
|||
*
|
||||
* \return - LZMA_OK
|
||||
* - LZMA_MEM_ERROR
|
||||
* - LZMA_PROG_ERROR
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_alone_decoder(
|
||||
lzma_stream *strm, uint64_t memlimit)
|
||||
|
@ -379,7 +387,7 @@ extern LZMA_API(lzma_ret) lzma_alone_decoder(
|
|||
* won't be read is in[in_size].
|
||||
* \param out Beginning of the output buffer
|
||||
* \param out_pos The next byte will be written to out[*out_pos].
|
||||
* *out_pos is updated only if encoding succeeds.
|
||||
* *out_pos is updated only if decoding succeeds.
|
||||
* \param out_size Size of the out buffer; the first byte into
|
||||
* which no data is written to is out[out_size].
|
||||
*
|
||||
|
|
|
@ -1,6 +1,6 @@
|
|||
/**
|
||||
* \file lzma/filter.h
|
||||
* \brief Common filter related types
|
||||
* \brief Common filter related types and functions
|
||||
*/
|
||||
|
||||
/*
|
||||
|
@ -59,11 +59,6 @@ typedef struct {
|
|||
* If the filter doesn't need options, set this to NULL. If id is
|
||||
* set to LZMA_VLI_UNKNOWN, options is ignored, and thus
|
||||
* doesn't need be initialized.
|
||||
*
|
||||
* Some filters support changing the options in the middle of
|
||||
* the encoding process. These filters store the pointer of the
|
||||
* options structure and communicate with the application via
|
||||
* modifications of the options structure.
|
||||
*/
|
||||
void *options;
|
||||
|
||||
|
@ -126,15 +121,16 @@ extern LZMA_API(lzma_ret) lzma_filters_copy(const lzma_filter *src,
|
|||
|
||||
|
||||
/**
|
||||
* \brief Calculate rough memory requirements for raw encoder
|
||||
* \brief Calculate approximate memory requirements for raw encoder
|
||||
*
|
||||
* Because the calculation is rough, this function can be used to calculate
|
||||
* the memory requirements for Block and Stream encoders too.
|
||||
* This function can be used to calculate the memory requirements for
|
||||
* Block and Stream encoders too because Block and Stream encoders don't
|
||||
* need significantly more memory than raw encoder.
|
||||
*
|
||||
* \param filters Array of filters terminated with
|
||||
* .id == LZMA_VLI_UNKNOWN.
|
||||
*
|
||||
* \return Rough number of bytes of memory required for the given
|
||||
* \return Number of bytes of memory required for the given
|
||||
* filter chain when encoding.
|
||||
*/
|
||||
extern LZMA_API(uint64_t) lzma_raw_encoder_memusage(const lzma_filter *filters)
|
||||
|
@ -142,15 +138,16 @@ extern LZMA_API(uint64_t) lzma_raw_encoder_memusage(const lzma_filter *filters)
|
|||
|
||||
|
||||
/**
|
||||
* \brief Calculate rough memory requirements for raw decoder
|
||||
* \brief Calculate approximate memory requirements for raw decoder
|
||||
*
|
||||
* Because the calculation is rough, this function can be used to calculate
|
||||
* the memory requirements for Block and Stream decoders too.
|
||||
* This function can be used to calculate the memory requirements for
|
||||
* Block and Stream decoders too because Block and Stream decoders don't
|
||||
* need significantly more memory than raw decoder.
|
||||
*
|
||||
* \param filters Array of filters terminated with
|
||||
* .id == LZMA_VLI_UNKNOWN.
|
||||
*
|
||||
* \return Rough number of bytes of memory required for the given
|
||||
* \return Number of bytes of memory required for the given
|
||||
* filter chain when decoding.
|
||||
*/
|
||||
extern LZMA_API(uint64_t) lzma_raw_decoder_memusage(const lzma_filter *filters)
|
||||
|
@ -251,7 +248,8 @@ extern LZMA_API(lzma_ret) lzma_filters_update(
|
|||
*
|
||||
* \note There is no function to calculate how big output buffer
|
||||
* would surely be big enough. (lzma_stream_buffer_bound()
|
||||
* works only for lzma_stream_buffer_encode().)
|
||||
* works only for lzma_stream_buffer_encode(); raw encoder
|
||||
* won't necessarily meet that bound.)
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_raw_buffer_encode(
|
||||
const lzma_filter *filters, lzma_allocator *allocator,
|
||||
|
@ -323,9 +321,10 @@ extern LZMA_API(lzma_ret) lzma_properties_size(
|
|||
* succeeds but using the same options to initialize the encoder
|
||||
* will fail.
|
||||
*
|
||||
* \note It is OK to skip calling this function if
|
||||
* lzma_properties_size() indicated that the size
|
||||
* of the Filter Properties field is zero.
|
||||
* \note If lzma_properties_size() indicated that the size
|
||||
* of the Filter Properties field is zero, calling
|
||||
* lzma_properties_encode() is not required, but it
|
||||
* won't do any harm either.
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_properties_encode(
|
||||
const lzma_filter *filter, uint8_t *props) lzma_nothrow;
|
||||
|
@ -364,11 +363,11 @@ extern LZMA_API(lzma_ret) lzma_properties_decode(
|
|||
* memory to hold the encoded Filter Flags.
|
||||
*
|
||||
* \param size Pointer to integer to hold the calculated size
|
||||
* \param filters Filter ID and associated options whose encoded
|
||||
* \param filter Filter ID and associated options whose encoded
|
||||
* size is to be calculated
|
||||
*
|
||||
* \return - LZMA_OK: *size set successfully. Note that this doesn't
|
||||
* guarantee that filters->options is valid, thus
|
||||
* guarantee that filter->options is valid, thus
|
||||
* lzma_filter_flags_encode() may still fail.
|
||||
* - LZMA_OPTIONS_ERROR: Unknown Filter ID or unsupported options.
|
||||
* - LZMA_PROG_ERROR: Invalid options
|
||||
|
@ -377,7 +376,7 @@ extern LZMA_API(lzma_ret) lzma_properties_decode(
|
|||
* you need to loop over every lzma_filter entry.
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_filter_flags_size(
|
||||
uint32_t *size, const lzma_filter *filters)
|
||||
uint32_t *size, const lzma_filter *filter)
|
||||
lzma_nothrow lzma_attr_warn_unused_result;
|
||||
|
||||
|
||||
|
@ -387,7 +386,7 @@ extern LZMA_API(lzma_ret) lzma_filter_flags_size(
|
|||
* In contrast to some functions, this doesn't allocate the needed buffer.
|
||||
* This is due to how this function is used internally by liblzma.
|
||||
*
|
||||
* \param filters Filter ID and options to be encoded
|
||||
* \param filter Filter ID and options to be encoded
|
||||
* \param out Beginning of the output buffer
|
||||
* \param out_pos out[*out_pos] is the next write position. This
|
||||
* is updated by the encoder.
|
||||
|
@ -399,7 +398,7 @@ extern LZMA_API(lzma_ret) lzma_filter_flags_size(
|
|||
* buffer space (you should have checked it with
|
||||
* lzma_filter_flags_size()).
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_filter_flags_encode(const lzma_filter *filters,
|
||||
extern LZMA_API(lzma_ret) lzma_filter_flags_encode(const lzma_filter *filter,
|
||||
uint8_t *out, size_t *out_pos, size_t out_size)
|
||||
lzma_nothrow lzma_attr_warn_unused_result;
|
||||
|
||||
|
@ -407,8 +406,8 @@ extern LZMA_API(lzma_ret) lzma_filter_flags_encode(const lzma_filter *filters,
|
|||
/**
|
||||
* \brief Decode Filter Flags from given buffer
|
||||
*
|
||||
* The decoded result is stored into *filters. filters->options is
|
||||
* initialized but the old value is NOT free()d.
|
||||
* The decoded result is stored into *filter. The old value of
|
||||
* filter->options is not free()d.
|
||||
*
|
||||
* \return - LZMA_OK
|
||||
* - LZMA_OPTIONS_ERROR
|
||||
|
@ -416,6 +415,6 @@ extern LZMA_API(lzma_ret) lzma_filter_flags_encode(const lzma_filter *filters,
|
|||
* - LZMA_PROG_ERROR
|
||||
*/
|
||||
extern LZMA_API(lzma_ret) lzma_filter_flags_decode(
|
||||
lzma_filter *filters, lzma_allocator *allocator,
|
||||
lzma_filter *filter, lzma_allocator *allocator,
|
||||
const uint8_t *in, size_t *in_pos, size_t in_size)
|
||||
lzma_nothrow lzma_attr_warn_unused_result;
|
||||
|
|
|
@ -39,8 +39,7 @@
|
|||
*
|
||||
* This function may be useful when determining a reasonable memory
|
||||
* usage limit for decompressing or how much memory it is OK to use
|
||||
* for compressing. For example, the default limit used by the xz
|
||||
* command line tool is 40 % of RAM.
|
||||
* for compressing.
|
||||
*
|
||||
* \return On success, the total amount of physical memory in bytes
|
||||
* is returned. If the amount of RAM cannot be determined,
|
||||
|
|
|
@ -136,6 +136,13 @@ typedef struct {
|
|||
*
|
||||
* This offset is relative to the beginning of the lzma_index
|
||||
* (i.e. usually the beginning of the .xz file).
|
||||
*
|
||||
* When doing random-access reading, it is possible that
|
||||
* the target offset is not exactly at Block boundary. One
|
||||
* will need to compare the target offset against
|
||||
* uncompressed_file_offset or uncompressed_stream_offset,
|
||||
* and possibly decode and throw away some amount of data
|
||||
* before reaching the target offset.
|
||||
*/
|
||||
lzma_vli uncompressed_file_offset;
|
||||
|
||||
|
@ -166,14 +173,8 @@ typedef struct {
|
|||
* \brief Uncompressed size of this Block
|
||||
*
|
||||
* You should pass this to the Block decoder if you will
|
||||
* decode this Block.
|
||||
*
|
||||
* When doing random-access reading, it is possible that
|
||||
* the target offset is not exactly at Block boundary. One
|
||||
* will need to compare the target offset against
|
||||
* uncompressed_file_offset or uncompressed_stream_offset,
|
||||
* and possibly decode and throw away some amount of data
|
||||
* before reaching the target offset.
|
||||
* decode this Block. It will allow the Block decoder to
|
||||
* validate the uncompressed size.
|
||||
*/
|
||||
lzma_vli uncompressed_size;
|
||||
|
||||
|
@ -181,7 +182,8 @@ typedef struct {
|
|||
* \brief Unpadded size of this Block
|
||||
*
|
||||
* You should pass this to the Block decoder if you will
|
||||
* decode this Block.
|
||||
* decode this Block. It will allow the Block decoder to
|
||||
* validate the unpadded size.
|
||||
*/
|
||||
lzma_vli unpadded_size;
|
||||
|
||||
|
@ -583,7 +585,9 @@ extern LZMA_API(lzma_index *) lzma_index_dup(
|
|||
* \param strm Pointer to properly prepared lzma_stream
|
||||
* \param i Pointer to lzma_index which should be encoded.
|
||||
*
|
||||
* The only valid action value for lzma_code() is LZMA_RUN.
|
||||
* The valid `action' values for lzma_code() are LZMA_RUN and LZMA_FINISH.
|
||||
* It is enough to use only one of them (you can choose freely; use LZMA_RUN
|
||||
* to support liblzma versions older than 5.0.0).
|
||||
*
|
||||
* \return - LZMA_OK: Initialization succeeded, continue with lzma_code().
|
||||
* - LZMA_MEM_ERROR
|
||||
|
@ -608,7 +612,9 @@ extern LZMA_API(lzma_ret) lzma_index_encoder(
|
|||
* \param memlimit How much memory the resulting lzma_index is
|
||||
* allowed to require.
|
||||
*
|
||||
* The only valid action value for lzma_code() is LZMA_RUN.
|
||||
* The valid `action' values for lzma_code() are LZMA_RUN and LZMA_FINISH.
|
||||
* It is enough to use only one of them (you can choose freely; use LZMA_RUN
|
||||
* to support liblzma versions older than 5.0.0).
|
||||
*
|
||||
* \return - LZMA_OK: Initialization succeeded, continue with lzma_code().
|
||||
* - LZMA_MEM_ERROR
|
||||
|
|
|
@ -1,6 +1,6 @@
|
|||
/**
|
||||
* \file lzma/index_hash.h
|
||||
* \brief Validates Index by using a hash function
|
||||
* \brief Validate Index by using a hash function
|
||||
*
|
||||
* Hashing makes it possible to use constant amount of memory to validate
|
||||
* Index of arbitrary size.
|
||||
|
|
|
@ -46,6 +46,10 @@
|
|||
* Match finder has major effect on both speed and compression ratio.
|
||||
* Usually hash chains are faster than binary trees.
|
||||
*
|
||||
* If you will use LZMA_SYNC_FLUSH often, the hash chains may be a better
|
||||
* choice, because binary trees get much higher compression ratio penalty
|
||||
* with LZMA_SYNC_FLUSH.
|
||||
*
|
||||
* The memory usage formulas are only rough estimates, which are closest to
|
||||
* reality when dict_size is a power of two. The formulas are more complex
|
||||
* in reality, and can also change a little between liblzma versions. Use
|
||||
|
@ -173,6 +177,7 @@ extern LZMA_API(lzma_bool) lzma_mode_is_supported(lzma_mode mode)
|
|||
* Since LZMA1 and LZMA2 share most of the code, it's simplest to share
|
||||
* the options structure too. For encoding, all but the reserved variables
|
||||
* need to be initialized unless specifically mentioned otherwise.
|
||||
* lzma_lzma_preset() can be used to get a good starting point.
|
||||
*
|
||||
* For raw decoding, both LZMA1 and LZMA2 need dict_size, preset_dict, and
|
||||
* preset_dict_size (if preset_dict != NULL). LZMA1 needs also lc, lp, and pb.
|
||||
|
@ -255,7 +260,13 @@ typedef struct {
|
|||
* eight-bit byte (also known as `literal') are taken into
|
||||
* account when predicting the bits of the next literal.
|
||||
*
|
||||
* \todo Example
|
||||
* E.g. in typical English text, an upper-case letter is
|
||||
* often followed by a lower-case letter, and a lower-case
|
||||
* letter is usually followed by another lower-case letter.
|
||||
* In the US-ASCII character set, the highest three bits are 010
|
||||
* for upper-case letters and 011 for lower-case letters.
|
||||
* When lc is at least 3, the literal coding can take advantage of
|
||||
* this property in the uncompressed data.
|
||||
*
|
||||
* There is a limit that applies to literal context bits and literal
|
||||
* position bits together: lc + lp <= 4. Without this limit the
|
||||
|
@ -275,12 +286,9 @@ typedef struct {
|
|||
/**
|
||||
* \brief Number of literal position bits
|
||||
*
|
||||
* How many of the lowest bits of the current position (number
|
||||
* of bytes from the beginning of the uncompressed data) in the
|
||||
* uncompressed data is taken into account when predicting the
|
||||
* bits of the next literal (a single eight-bit byte).
|
||||
*
|
||||
* \todo Example
|
||||
* lp affects what kind of alignment in the uncompressed data is
|
||||
* assumed when encoding literals. A literal is a single 8-bit byte.
|
||||
* See pb below for more information about alignment.
|
||||
*/
|
||||
uint32_t lp;
|
||||
# define LZMA_LP_DEFAULT 0
|
||||
|
@ -288,14 +296,22 @@ typedef struct {
|
|||
/**
|
||||
* \brief Number of position bits
|
||||
*
|
||||
* How many of the lowest bits of the current position in the
|
||||
* uncompressed data is taken into account when estimating
|
||||
* probabilities of matches. A match is a sequence of bytes for
|
||||
* which a matching sequence is found from the dictionary and
|
||||
* thus can be stored as distance-length pair.
|
||||
* pb affects what kind of alignment in the uncompressed data is
|
||||
* assumed in general. The default means four-byte alignment
|
||||
* (2^ pb =2^2=4), which is often a good choice when there's
|
||||
* no better guess.
|
||||
*
|
||||
* Example: If most of the matches occur at byte positions of
|
||||
* 8 * n + 3, that is, 3, 11, 19, ... set pb to 3, because 2**3 == 8.
|
||||
* When the aligment is known, setting pb accordingly may reduce
|
||||
* the file size a little. E.g. with text files having one-byte
|
||||
* alignment (US-ASCII, ISO-8859-*, UTF-8), setting pb=0 can
|
||||
* improve compression slightly. For UTF-16 text, pb=1 is a good
|
||||
* choice. If the alignment is an odd number like 3 bytes, pb=0
|
||||
* might be the best choice.
|
||||
*
|
||||
* Even though the assumed alignment can be adjusted with pb and
|
||||
* lp, LZMA1 and LZMA2 still slightly favor 16-byte alignment.
|
||||
* It might be worth taking into account when designing file formats
|
||||
* that are likely to be often compressed with LZMA1 or LZMA2.
|
||||
*/
|
||||
uint32_t pb;
|
||||
# define LZMA_PB_MIN 0
|
||||
|
@ -346,7 +362,7 @@ typedef struct {
|
|||
*
|
||||
* Setting depth to zero tells liblzma to use an automatic default
|
||||
* value, that depends on the selected match finder and nice_len.
|
||||
* The default is in the range [10, 200] or so (it may vary between
|
||||
* The default is in the range [4, 200] or so (it may vary between
|
||||
* liblzma versions).
|
||||
*
|
||||
* Using a bigger depth value than the default can increase
|
||||
|
|
|
@ -148,7 +148,7 @@ extern LZMA_API(lzma_ret) lzma_stream_footer_encode(
|
|||
/**
|
||||
* \brief Decode Stream Header
|
||||
*
|
||||
* \param options Stream Header options to be encoded.
|
||||
* \param options Target for the decoded Stream Header options.
|
||||
* \param in Beginning of the input buffer of
|
||||
* LZMA_STREAM_HEADER_SIZE bytes.
|
||||
*
|
||||
|
@ -183,7 +183,7 @@ extern LZMA_API(lzma_ret) lzma_stream_header_decode(
|
|||
/**
|
||||
* \brief Decode Stream Footer
|
||||
*
|
||||
* \param options Stream Header options to be encoded.
|
||||
* \param options Target for the decoded Stream Header options.
|
||||
* \param in Beginning of the input buffer of
|
||||
* LZMA_STREAM_HEADER_SIZE bytes.
|
||||
*
|
||||
|
|
|
@ -29,7 +29,7 @@
|
|||
|
||||
|
||||
/**
|
||||
* \brief Maximum supported value of variable-length integer
|
||||
* \brief Maximum supported value of a variable-length integer
|
||||
*/
|
||||
#define LZMA_VLI_MAX (UINT64_MAX / 2)
|
||||
|
||||
|
@ -39,11 +39,10 @@
|
|||
#define LZMA_VLI_UNKNOWN UINT64_MAX
|
||||
|
||||
/**
|
||||
* \brief Maximum supported length of variable length integers
|
||||
* \brief Maximum supported encoded length of variable length integers
|
||||
*/
|
||||
#define LZMA_VLI_BYTES_MAX 9
|
||||
|
||||
|
||||
/**
|
||||
* \brief VLI constant suffix
|
||||
*/
|
||||
|
@ -53,19 +52,19 @@
|
|||
/**
|
||||
* \brief Variable-length integer type
|
||||
*
|
||||
* This will always be unsigned integer. Valid VLI values are in the range
|
||||
* [0, LZMA_VLI_MAX]. Unknown value is indicated with LZMA_VLI_UNKNOWN,
|
||||
* which is the maximum value of the underlaying integer type.
|
||||
* Valid VLI values are in the range [0, LZMA_VLI_MAX]. Unknown value is
|
||||
* indicated with LZMA_VLI_UNKNOWN, which is the maximum value of the
|
||||
* underlaying integer type.
|
||||
*
|
||||
* In future, even if lzma_vli is defined to be something other than uint64_t,
|
||||
* it is guaranteed that 2 * LZMA_VLI_MAX will not overflow lzma_vli.
|
||||
* This simplifies integer overflow detection.
|
||||
* lzma_vli will be uint64_t for the foreseeable future. If a bigger size
|
||||
* is needed in the future, it is guaranteed that 2 * LZMA_VLI_MAX will
|
||||
* not overflow lzma_vli. This simplifies integer overflow detection.
|
||||
*/
|
||||
typedef uint64_t lzma_vli;
|
||||
|
||||
|
||||
/**
|
||||
* \brief Simple macro to validate variable-length integer
|
||||
* \brief Validate a variable-length integer
|
||||
*
|
||||
* This is useful to test that application has given acceptable values
|
||||
* for example in the uncompressed_size and compressed_size variables.
|
||||
|
@ -88,9 +87,9 @@ typedef uint64_t lzma_vli;
|
|||
*
|
||||
* \param vli Integer to be encoded
|
||||
* \param vli_pos How many VLI-encoded bytes have already been written
|
||||
* out. When starting to encode a new integer, *vli_pos
|
||||
* must be set to zero. To use single-call encoding,
|
||||
* set vli_pos to NULL.
|
||||
* out. When starting to encode a new integer in
|
||||
* multi-call mode, *vli_pos must be set to zero.
|
||||
* To use single-call encoding, set vli_pos to NULL.
|
||||
* \param out Beginning of the output buffer
|
||||
* \param out_pos The next byte will be written to out[*out_pos].
|
||||
* \param out_size Size of the out buffer; the first byte into
|
||||
|
@ -126,9 +125,9 @@ extern LZMA_API(lzma_ret) lzma_vli_encode(lzma_vli vli, size_t *vli_pos,
|
|||
* initialize it to zero when *vli_pos == 0, so
|
||||
* application isn't required to initialize *vli.
|
||||
* \param vli_pos How many bytes have already been decoded. When
|
||||
* starting to decode a new integer, *vli_pos must
|
||||
* be initialized to zero. To use single-call decoding,
|
||||
* set this to NULL.
|
||||
* starting to decode a new integer in multi-call
|
||||
* mode, *vli_pos must be initialized to zero. To
|
||||
* use single-call decoding, set vli_pos to NULL.
|
||||
* \param in Beginning of the input buffer
|
||||
* \param in_pos The next byte will be read from in[*in_pos].
|
||||
* \param in_size Size of the input buffer; the first byte that
|
||||
|
|
|
@ -291,6 +291,7 @@ lzma_index_decoder(lzma_stream *strm, lzma_index **i, uint64_t memlimit)
|
|||
lzma_next_strm_init(index_decoder_init, strm, i, memlimit);
|
||||
|
||||
strm->internal->supported_actions[LZMA_RUN] = true;
|
||||
strm->internal->supported_actions[LZMA_FINISH] = true;
|
||||
|
||||
return LZMA_OK;
|
||||
}
|
||||
|
|
|
@ -209,6 +209,7 @@ lzma_index_encoder(lzma_stream *strm, const lzma_index *i)
|
|||
lzma_next_strm_init(lzma_index_encoder_init, strm, i);
|
||||
|
||||
strm->internal->supported_actions[LZMA_RUN] = true;
|
||||
strm->internal->supported_actions[LZMA_FINISH] = true;
|
||||
|
||||
return LZMA_OK;
|
||||
}
|
||||
|
|
Loading…
Reference in New Issue