| 1 | /* |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This source code is licensed under both the BSD-style license (found in the |
| 6 | * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
| 7 | * in the COPYING file in the root directory of this source tree). |
| 8 | * You may select, at your option, one of the above-listed licenses. |
| 9 | */ |
| 10 | |
| 11 | #include <stddef.h> /* size_t */ |
| 12 | |
| 13 | /******* EXPOSED TYPES ********************************************************/ |
| 14 | /* |
| 15 | * Contains the parsed contents of a dictionary |
| 16 | * This includes Huffman and FSE tables used for decoding and data on offsets |
| 17 | */ |
| 18 | typedef struct dictionary_s dictionary_t; |
| 19 | /******* END EXPOSED TYPES ****************************************************/ |
| 20 | |
| 21 | /******* DECOMPRESSION FUNCTIONS **********************************************/ |
| 22 | /// Zstandard decompression functions. |
| 23 | /// `dst` must point to a space at least as large as the reconstructed output. |
| 24 | size_t ZSTD_decompress(void *const dst, const size_t dst_len, |
| 25 | const void *const src, const size_t src_len); |
| 26 | |
| 27 | /// If `dict != NULL` and `dict_len >= 8`, does the same thing as |
| 28 | /// `ZSTD_decompress` but uses the provided dict |
| 29 | size_t ZSTD_decompress_with_dict(void *const dst, const size_t dst_len, |
| 30 | const void *const src, const size_t src_len, |
| 31 | dictionary_t* parsed_dict); |
| 32 | |
| 33 | /// Get the decompressed size of an input stream so memory can be allocated in |
| 34 | /// advance |
| 35 | /// Returns -1 if the size can't be determined |
| 36 | /// Assumes decompression of a single frame |
| 37 | size_t ZSTD_get_decompressed_size(const void *const src, const size_t src_len); |
| 38 | /******* END DECOMPRESSION FUNCTIONS ******************************************/ |
| 39 | |
| 40 | /******* DICTIONARY MANAGEMENT ***********************************************/ |
| 41 | /* |
| 42 | * Return a valid dictionary_t pointer for use with dictionary initialization |
| 43 | * or decompression |
| 44 | */ |
| 45 | dictionary_t* create_dictionary(void); |
| 46 | |
| 47 | /* |
| 48 | * Parse a provided dictionary blob for use in decompression |
| 49 | * `src` -- must point to memory space representing the dictionary |
| 50 | * `src_len` -- must provide the dictionary size |
| 51 | * `dict` -- will contain the parsed contents of the dictionary and |
| 52 | * can be used for decompression |
| 53 | */ |
| 54 | void parse_dictionary(dictionary_t *const dict, const void *src, |
| 55 | size_t src_len); |
| 56 | |
| 57 | /* |
| 58 | * Free internal Huffman tables, FSE tables, and dictionary content |
| 59 | */ |
| 60 | void free_dictionary(dictionary_t *const dict); |
| 61 | /******* END DICTIONARY MANAGEMENT *******************************************/ |