| /** |
| * \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_options_filter; |
| |
| |
| /** |
| * \brief Filters available for encoding |
| * |
| * Pointer to an array containing the list of available Filter IDs that |
| * can be used for encoding. The last element is LZMA_VLI_VALUE_UNKNOWN. |
| * |
| * If lzma_available_filter_encoders[0] == LZMA_VLI_VALUE_UNKNOWN, the |
| * encoder components haven't been built at all. This means that the |
| * encoding-specific functions are probably missing from the library |
| * API/ABI completely. |
| */ |
| extern const lzma_vli *const lzma_available_filter_encoders; |
| |
| |
| /** |
| * \brief Filters available for decoding |
| * |
| * Pointer to an array containing the list of available Filter IDs that |
| * can be used for decoding. The last element is LZMA_VLI_VALUE_UNKNOWN. |
| * |
| * If lzma_available_filter_decoders[0] == LZMA_VLI_VALUE_UNKNOWN, the |
| * decoder components haven't been built at all. This means that the |
| * decoding-specific functions are probably missing from the library |
| * API/ABI completely. |
| */ |
| extern const lzma_vli *const lzma_available_filter_decoders; |
| |
| |
| /** |
| * \brief Calculate rough memory requirements for given filter chain |
| * |
| * \param filters Array of filters terminated with |
| * .id == LZMA_VLI_VALUE_UNKNOWN. |
| * \param is_encoder Set to true when calculating memory requirements |
| * of an encoder; false for decoder. |
| * |
| * \return Number of mebibytes (MiB i.e. 2^20) required for the given |
| * encoder or decoder filter chain. |
| * |
| * \note If calculating memory requirements of encoder, lzma_init() or |
| * lzma_init_encoder() must have been called earlier. Similarly, |
| * if calculating memory requirements of decoder, lzma_init() or |
| * lzma_init_decoder() must have been called earlier. |
| */ |
| extern uint32_t lzma_memory_usage( |
| const lzma_options_filter *filters, lzma_bool is_encoder); |
| |
| |
| /** |
| * \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_options_filter entry. |
| */ |
| extern lzma_ret lzma_filter_flags_size( |
| uint32_t *size, const lzma_options_filter *options); |
| |
| |
| /** |
| * \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(uint8_t *out, size_t *out_pos, |
| size_t out_size, const lzma_options_filter *options); |
| |
| |
| /** |
| * \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_decoder( |
| lzma_stream *strm, lzma_options_filter *options); |