| /** |
| * \file lzma/filter.h |
| * \brief Common filter related types |
| * |
| * \author Copyright (C) 1999-2006 Igor Pavlov |
| * \author Copyright (C) 2007 Lasse Collin |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| */ |
| |
| #ifndef LZMA_H_INTERNAL |
| # error Never include this file directly. Use <lzma.h> instead. |
| #endif |
| |
| |
| /** |
| * \brief Filter options |
| * |
| * This structure is used to pass Filter ID and a pointer filter's options |
| * to liblzma. |
| */ |
| typedef struct { |
| /** |
| * \brief Filter ID |
| * |
| * Use constants whose name begin with `LZMA_FILTER_' to specify |
| * different filters. In an array of lzma_option_filter structures, |
| * use LZMA_VLI_VALUE_UNKNOWN to indicate end of filters. |
| */ |
| 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_VALUE_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; |
| |
| } lzma_filter; |
| |
| |
| /** |
| * \brief Test if the given Filter ID is supported for encoding |
| * |
| * Returns 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_bool lzma_filter_encoder_is_supported(lzma_vli id); |
| |
| |
| /** |
| * \brief Test if the given Filter ID is supported for decoding |
| * |
| * Returns true if the give Filter ID is supported for decoding by this |
| * liblzma build. Otherwise false is returned. |
| */ |
| extern lzma_bool lzma_filter_decoder_is_supported(lzma_vli id); |
| |
| |
| /** |
| * \brief Calculate rough memory requirements for raw encoder |
| * |
| * \param filters Array of filters terminated with |
| * .id == LZMA_VLI_VALUE_UNKNOWN. |
| * |
| * \return Rough number of bytes required for the given filter chain |
| * when encoding. |
| */ |
| extern uint64_t lzma_memusage_encoder(const lzma_filter *filters) |
| lzma_attr_pure; |
| |
| |
| /** |
| * \brief Calculate rough memory requirements for raw decoder |
| * |
| * \param filters Array of filters terminated with |
| * .id == LZMA_VLI_VALUE_UNKNOWN. |
| * |
| * \return Rough number of bytes required for the given filter chain |
| * when decoding. |
| */ |
| extern uint64_t lzma_memusage_decoder(const lzma_filter *filters) |
| 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 options Array of lzma_filter structures. |
| * The end of the array must be marked with |
| * .id = LZMA_VLI_VALUE_UNKNOWN. The minimum |
| * number of filters is one and the maximum is four. |
| * |
| * 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_HEADER_ERROR |
| * - LZMA_PROG_ERROR |
| */ |
| extern lzma_ret lzma_raw_encoder( |
| lzma_stream *strm, const lzma_filter *options) |
| 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_HEADER_ERROR |
| * - LZMA_PROG_ERROR |
| */ |
| extern lzma_ret lzma_raw_decoder( |
| lzma_stream *strm, const lzma_filter *options) |
| lzma_attr_warn_unused_result; |
| |
| |
| /** |
| * \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 propeties may |
| * vary depending on the options) |
| * |
| * \return - LZMA_OK |
| * - LZMA_HEADER_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_HEADER_ERROR. |
| */ |
| extern lzma_ret lzma_properties_size( |
| uint32_t *size, const lzma_filter *filter); |
| |
| |
| /** |
| * \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_HEADER_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 It is OK to skip calling this function if |
| * lzma_properties_size() indicated that the size |
| * of the Filter Properties field is zero. |
| */ |
| extern lzma_ret lzma_properties_encode( |
| const lzma_filter *filter, uint8_t *props); |
| |
| |
| /** |
| * \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 to filter->options. |
| * 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_HEADER_ERROR. |
| * |
| * \return - LZMA_OK |
| * - LZMA_HEADER_ERROR |
| * - LZMA_MEM_ERROR |
| */ |
| extern lzma_ret lzma_properties_decode( |
| lzma_filter *filter, lzma_allocator *allocator, |
| const uint8_t *props, size_t props_size); |
| |
| |
| /** |
| * \brief Calculates 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 options Filter ID and associated options whose encoded |
| * size is to be calculted |
| * |
| * \return - LZMA_OK: *size set successfully. Note that this doesn't |
| * guarantee that options->options is valid, thus |
| * lzma_filter_flags_encode() may still fail. |
| * - LZMA_HEADER_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_ret lzma_filter_flags_size( |
| uint32_t *size, const lzma_filter *options) |
| lzma_attr_warn_unused_result; |
| |
| |
| /** |
| * \brief Encodes 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 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. |
| * \param options Filter options to be encoded |
| * |
| * \return - LZMA_OK: Encoding was successful. |
| * - LZMA_HEADER_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_ret lzma_filter_flags_encode(const lzma_filter *options, |
| uint8_t *out, size_t *out_pos, size_t out_size) |
| lzma_attr_warn_unused_result; |
| |
| |
| /** |
| * \brief Initializes Filter Flags decoder |
| * |
| * The decoded result is stored into *options. options->options is |
| * initialized but the old value is NOT free()d. |
| * |
| * Because the results of this decoder are placed into *options, |
| * strm->next_in, strm->avail_in, and strm->total_in are not used |
| * when calling lzma_code(). The only valid action for lzma_code() |
| * is LZMA_RUN |
| * |
| * \return - LZMA_OK |
| * - LZMA_MEM_ERROR |
| * - LZMA_PROG_ERROR |
| */ |
| extern lzma_ret lzma_filter_flags_decode( |
| lzma_filter *options, lzma_allocator *allocator, |
| const uint8_t *in, size_t *in_pos, size_t in_size) |
| lzma_attr_warn_unused_result; |
