| /** |
| * \file lzma/filter.h |
| * \brief Common filter related types and functions |
| */ |
| |
| /* |
| * Author: Lasse Collin |
| * |
| * This file has been put into the public domain. |
| * You can do whatever you want with this file. |
| * |
| * See ../lzma.h for information about liblzma as a whole. |
| */ |
| |
| #ifndef LZMA_H_INTERNAL |
| # error Never include this file directly. Use <lzma.h> instead. |
| #endif |
| |
| |
| /** |
| * \brief Maximum number of filters in a chain |
| * |
| * A filter chain can have 1-4 filters, of which three are allowed to change |
| * the size of the data. Usually only one or two filters are needed. |
| */ |
| #define LZMA_FILTERS_MAX 4 |
| |
| |
| /** |
| * \brief Filter options |
| * |
| * This structure is used to pass Filter ID and a pointer filter's |
| * options to liblzma. A few functions work with a single lzma_filter |
| * structure, while most functions expect a filter chain. |
| * |
| * A filter chain is indicated with an array of lzma_filter structures. |
| * The array is terminated with .id = LZMA_VLI_UNKNOWN. Thus, the filter |
| * array must have LZMA_FILTERS_MAX + 1 elements (that is, five) to |
| * be able to hold any arbitrary filter chain. This is important when |
| * using lzma_block_header_decode() from block.h, because too small |
| * array would make liblzma write past the end of the filters array. |
| */ |
| typedef struct { |
| /** |
| * \brief Filter ID |
| * |
| * Use constants whose name begin with `LZMA_FILTER_' to specify |
| * different filters. In an array of lzma_filter structures, use |
| * LZMA_VLI_UNKNOWN to indicate end of filters. |
| * |
| * \note This is not an enum, because on some systems enums |
| * cannot be 64-bit. |
| */ |
| lzma_vli id; |
| |
| /** |
| * \brief Pointer to filter-specific options structure |
| * |
| * 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. |
| */ |
| void *options; |
| |
| } lzma_filter; |
| |
| |
| /** |
| * \brief Test if the given Filter ID is supported for encoding |
| * |
| * Return true if the give Filter ID is supported for encoding by this |
| * liblzma build. Otherwise false is returned. |
| * |
| * There is no way to list which filters are available in this particular |
| * liblzma version and build. It would be useless, because the application |
| * couldn't know what kind of options the filter would need. |
| */ |
| extern LZMA_API(lzma_bool) lzma_filter_encoder_is_supported(lzma_vli id) |
| lzma_nothrow lzma_attr_const; |
| |
| |
| /** |
| * \brief Test if the given Filter ID is supported for decoding |
| * |
| * Return true if the give Filter ID is supported for decoding by this |
| * liblzma build. Otherwise false is returned. |
| */ |
| extern LZMA_API(lzma_bool) lzma_filter_decoder_is_supported(lzma_vli id) |
| lzma_nothrow lzma_attr_const; |
| |
| |
| /** |
| * \brief Copy the filters array |
| * |
| * Copy the Filter IDs and filter-specific options from src to dest. |
| * Up to LZMA_FILTERS_MAX filters are copied, plus the terminating |
| * .id == LZMA_VLI_UNKNOWN. Thus, dest should have at least |
| * LZMA_FILTERS_MAX + 1 elements space unless the caller knows that |
| * src is smaller than that. |
| * |
| * Unless the filter-specific options is NULL, the Filter ID has to be |
| * supported by liblzma, because liblzma needs to know the size of every |
| * filter-specific options structure. The filter-specific options are not |
| * validated. If options is NULL, any unsupported Filter IDs are copied |
| * without returning an error. |
| * |
| * Old filter-specific options in dest are not freed, so dest doesn't |
| * need to be initialized by the caller in any way. |
| * |
| * If an error occurs, memory possibly already allocated by this function |
| * is always freed. |
| * |
| * \return - LZMA_OK |
| * - LZMA_MEM_ERROR |
| * - LZMA_OPTIONS_ERROR: Unsupported Filter ID and its options |
| * is not NULL. |
| * - LZMA_PROG_ERROR: src or dest is NULL. |
| */ |
| extern LZMA_API(lzma_ret) lzma_filters_copy( |
| const lzma_filter *src, lzma_filter *dest, |
| const lzma_allocator *allocator) lzma_nothrow; |
| |
| |
| /** |
| * \brief Calculate approximate memory requirements for raw encoder |
| * |
| * 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 Number of bytes of memory required for the given |
| * filter chain when encoding. If an error occurs, |
| * for example due to unsupported filter chain, |
| * UINT64_MAX is returned. |
| */ |
| extern LZMA_API(uint64_t) lzma_raw_encoder_memusage(const lzma_filter *filters) |
| lzma_nothrow lzma_attr_pure; |
| |
| |
| /** |
| * \brief Calculate approximate memory requirements for raw decoder |
| * |
| * 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 Number of bytes of memory required for the given |
| * filter chain when decoding. If an error occurs, |
| * for example due to unsupported filter chain, |
| * UINT64_MAX is returned. |
| */ |
| extern LZMA_API(uint64_t) lzma_raw_decoder_memusage(const lzma_filter *filters) |
| lzma_nothrow lzma_attr_pure; |
| |
| |
| /** |
| * \brief Initialize raw encoder |
| * |
| * This function may be useful when implementing custom file formats. |
| * |
| * \param strm Pointer to properly prepared lzma_stream |
| * \param filters Array of lzma_filter structures. The end of the |
| * array must be marked with .id = LZMA_VLI_UNKNOWN. |
| * |
| * The `action' with lzma_code() can be LZMA_RUN, LZMA_SYNC_FLUSH (if the |
| * filter chain supports it), or LZMA_FINISH. |
| * |
| * \return - LZMA_OK |
| * - LZMA_MEM_ERROR |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_PROG_ERROR |
| */ |
| extern LZMA_API(lzma_ret) lzma_raw_encoder( |
| lzma_stream *strm, const lzma_filter *filters) |
| lzma_nothrow lzma_attr_warn_unused_result; |
| |
| |
| /** |
| * \brief Initialize raw decoder |
| * |
| * The initialization of raw decoder goes similarly to raw encoder. |
| * |
| * The `action' with lzma_code() can be LZMA_RUN or LZMA_FINISH. Using |
| * LZMA_FINISH is not required, it is supported just for convenience. |
| * |
| * \return - LZMA_OK |
| * - LZMA_MEM_ERROR |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_PROG_ERROR |
| */ |
| extern LZMA_API(lzma_ret) lzma_raw_decoder( |
| lzma_stream *strm, const lzma_filter *filters) |
| lzma_nothrow lzma_attr_warn_unused_result; |
| |
| |
| /** |
| * \brief Update the filter chain in the encoder |
| * |
| * This function is for advanced users only. This function has two slightly |
| * different purposes: |
| * |
| * - After LZMA_FULL_FLUSH when using Stream encoder: Set a new filter |
| * chain, which will be used starting from the next Block. |
| * |
| * - After LZMA_SYNC_FLUSH using Raw, Block, or Stream encoder: Change |
| * the filter-specific options in the middle of encoding. The actual |
| * filters in the chain (Filter IDs) cannot be changed. In the future, |
| * it might become possible to change the filter options without |
| * using LZMA_SYNC_FLUSH. |
| * |
| * While rarely useful, this function may be called also when no data has |
| * been compressed yet. In that case, this function will behave as if |
| * LZMA_FULL_FLUSH (Stream encoder) or LZMA_SYNC_FLUSH (Raw or Block |
| * encoder) had been used right before calling this function. |
| * |
| * \return - LZMA_OK |
| * - LZMA_MEM_ERROR |
| * - LZMA_MEMLIMIT_ERROR |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_PROG_ERROR |
| */ |
| extern LZMA_API(lzma_ret) lzma_filters_update( |
| lzma_stream *strm, const lzma_filter *filters) lzma_nothrow; |
| |
| |
| /** |
| * \brief Single-call raw encoder |
| * |
| * \param filters Array of lzma_filter structures. The end of the |
| * array must be marked with .id = LZMA_VLI_UNKNOWN. |
| * \param allocator lzma_allocator for custom allocator functions. |
| * Set to NULL to use malloc() and free(). |
| * \param in Beginning of the input buffer |
| * \param in_size Size of the input buffer |
| * \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. |
| * \param out_size Size of the out buffer; the first byte into |
| * which no data is written to is out[out_size]. |
| * |
| * \return - LZMA_OK: Encoding was successful. |
| * - LZMA_BUF_ERROR: Not enough output buffer space. |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_MEM_ERROR |
| * - LZMA_DATA_ERROR |
| * - LZMA_PROG_ERROR |
| * |
| * \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(); raw encoder |
| * won't necessarily meet that bound.) |
| */ |
| extern LZMA_API(lzma_ret) lzma_raw_buffer_encode( |
| const lzma_filter *filters, const lzma_allocator *allocator, |
| const uint8_t *in, size_t in_size, uint8_t *out, |
| size_t *out_pos, size_t out_size) lzma_nothrow; |
| |
| |
| /** |
| * \brief Single-call raw decoder |
| * |
| * \param filters Array of lzma_filter structures. The end of the |
| * array must be marked with .id = LZMA_VLI_UNKNOWN. |
| * \param allocator lzma_allocator for custom allocator functions. |
| * Set to NULL to use malloc() and free(). |
| * \param in Beginning of the input buffer |
| * \param in_pos The next byte will be read from in[*in_pos]. |
| * *in_pos is updated only if decoding succeeds. |
| * \param in_size Size of the input buffer; the first byte that |
| * 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. |
| * \param out_size Size of the out buffer; the first byte into |
| * which no data is written to is out[out_size]. |
| */ |
| extern LZMA_API(lzma_ret) lzma_raw_buffer_decode( |
| const lzma_filter *filters, const lzma_allocator *allocator, |
| const uint8_t *in, size_t *in_pos, size_t in_size, |
| uint8_t *out, size_t *out_pos, size_t out_size) lzma_nothrow; |
| |
| |
| /** |
| * \brief Get the size of the Filter Properties field |
| * |
| * This function may be useful when implementing custom file formats |
| * using the raw encoder and decoder. |
| * |
| * \param size Pointer to uint32_t to hold the size of the properties |
| * \param filter Filter ID and options (the size of the properties may |
| * vary depending on the options) |
| * |
| * \return - LZMA_OK |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_PROG_ERROR |
| * |
| * \note This function validates the Filter ID, but does not |
| * necessarily validate the options. Thus, it is possible |
| * that this returns LZMA_OK while the following call to |
| * lzma_properties_encode() returns LZMA_OPTIONS_ERROR. |
| */ |
| extern LZMA_API(lzma_ret) lzma_properties_size( |
| uint32_t *size, const lzma_filter *filter) lzma_nothrow; |
| |
| |
| /** |
| * \brief Encode the Filter Properties field |
| * |
| * \param filter Filter ID and options |
| * \param props Buffer to hold the encoded options. The size of |
| * buffer must have been already determined with |
| * lzma_properties_size(). |
| * |
| * \return - LZMA_OK |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_PROG_ERROR |
| * |
| * \note Even this function won't validate more options than actually |
| * necessary. Thus, it is possible that encoding the properties |
| * succeeds but using the same options to initialize the encoder |
| * will fail. |
| * |
| * \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; |
| |
| |
| /** |
| * \brief Decode the Filter Properties field |
| * |
| * \param filter filter->id must have been set to the correct |
| * Filter ID. filter->options doesn't need to be |
| * initialized (it's not freed by this function). The |
| * decoded options will be stored in filter->options; |
| * it's application's responsibility to free it when |
| * appropriate. filter->options is set to NULL if |
| * there are no properties or if an error occurs. |
| * \param allocator Custom memory allocator used to allocate the |
| * options. Set to NULL to use the default malloc(), |
| * and in case of an error, also free(). |
| * \param props Input buffer containing the properties. |
| * \param props_size Size of the properties. This must be the exact |
| * size; giving too much or too little input will |
| * return LZMA_OPTIONS_ERROR. |
| * |
| * \return - LZMA_OK |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_MEM_ERROR |
| */ |
| extern LZMA_API(lzma_ret) lzma_properties_decode( |
| lzma_filter *filter, const lzma_allocator *allocator, |
| const uint8_t *props, size_t props_size) lzma_nothrow; |
| |
| |
| /** |
| * \brief Calculate encoded size of a Filter Flags field |
| * |
| * Knowing the size of Filter Flags is useful to know when allocating |
| * memory to hold the encoded Filter Flags. |
| * |
| * \param size Pointer to integer to hold the calculated size |
| * \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 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 |
| * |
| * \note If you need to calculate size of List of Filter Flags, |
| * you need to loop over every lzma_filter entry. |
| */ |
| extern LZMA_API(lzma_ret) lzma_filter_flags_size( |
| uint32_t *size, const lzma_filter *filter) |
| lzma_nothrow lzma_attr_warn_unused_result; |
| |
| |
| /** |
| * \brief Encode Filter Flags into given buffer |
| * |
| * 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 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. |
| * \param out_size out[out_size] is the first byte to not write. |
| * |
| * \return - LZMA_OK: Encoding was successful. |
| * - LZMA_OPTIONS_ERROR: Invalid or unsupported options. |
| * - LZMA_PROG_ERROR: Invalid options or not enough output |
| * buffer space (you should have checked it with |
| * lzma_filter_flags_size()). |
| */ |
| 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; |
| |
| |
| /** |
| * \brief Decode Filter Flags from given buffer |
| * |
| * The decoded result is stored into *filter. The old value of |
| * filter->options is not free()d. |
| * |
| * \return - LZMA_OK |
| * - LZMA_OPTIONS_ERROR |
| * - LZMA_MEM_ERROR |
| * - LZMA_PROG_ERROR |
| */ |
| extern LZMA_API(lzma_ret) lzma_filter_flags_decode( |
| lzma_filter *filter, const lzma_allocator *allocator, |
| const uint8_t *in, size_t *in_pos, size_t in_size) |
| lzma_nothrow lzma_attr_warn_unused_result; |
