| Alexandre Lision | 8af73cb | 2013-12-10 14:11:20 -0500 | [diff] [blame] | 1 | /* $Id$ */ |
| 2 | /* |
| 3 | * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| 4 | * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | #ifndef __PJLIB_UTIL_CRC32_H__ |
| 21 | #define __PJLIB_UTIL_CRC32_H__ |
| 22 | |
| 23 | /** |
| 24 | * @file crc32.h |
| 25 | * @brief CRC32 implementation |
| 26 | */ |
| 27 | |
| 28 | #include <pjlib-util/types.h> |
| 29 | |
| 30 | PJ_BEGIN_DECL |
| 31 | |
| 32 | /** |
| 33 | * @defgroup PJLIB_UTIL_CRC32 CRC32 (Cyclic Redundancy Check) |
| 34 | * @ingroup PJLIB_UTIL_ENCRYPTION |
| 35 | * @{ |
| 36 | * This implements CRC32 algorithm. See ITU-T V.42 for the formal |
| 37 | * specification. |
| 38 | */ |
| 39 | |
| 40 | /** CRC32 context. */ |
| 41 | typedef struct pj_crc32_context |
| 42 | { |
| 43 | pj_uint32_t crc_state; /**< Current state. */ |
| 44 | } pj_crc32_context; |
| 45 | |
| 46 | |
| 47 | /** |
| 48 | * Initialize CRC32 context. |
| 49 | * |
| 50 | * @param ctx CRC32 context. |
| 51 | */ |
| 52 | PJ_DECL(void) pj_crc32_init(pj_crc32_context *ctx); |
| 53 | |
| 54 | /** |
| 55 | * Feed data incrementally to the CRC32 algorithm. |
| 56 | * |
| 57 | * @param ctx CRC32 context. |
| 58 | * @param data Input data. |
| 59 | * @param nbytes Length of the input data. |
| 60 | * |
| 61 | * @return The current CRC32 value. |
| 62 | */ |
| 63 | PJ_DECL(pj_uint32_t) pj_crc32_update(pj_crc32_context *ctx, |
| 64 | const pj_uint8_t *data, |
| 65 | pj_size_t nbytes); |
| 66 | |
| 67 | /** |
| 68 | * Finalize CRC32 calculation and retrieve the CRC32 value. |
| 69 | * |
| 70 | * @param ctx CRC32 context. |
| 71 | * |
| 72 | * @return The current CRC value. |
| 73 | */ |
| 74 | PJ_DECL(pj_uint32_t) pj_crc32_final(pj_crc32_context *ctx); |
| 75 | |
| 76 | /** |
| 77 | * Perform one-off CRC32 calculation to the specified data. |
| 78 | * |
| 79 | * @param data Input data. |
| 80 | * @param nbytes Length of input data. |
| 81 | * |
| 82 | * @return CRC value of the data. |
| 83 | */ |
| 84 | PJ_DECL(pj_uint32_t) pj_crc32_calc(const pj_uint8_t *data, |
| 85 | pj_size_t nbytes); |
| 86 | |
| 87 | |
| 88 | /** |
| 89 | * @} |
| 90 | */ |
| 91 | |
| 92 | PJ_END_DECL |
| 93 | |
| 94 | |
| 95 | #endif /* __PJLIB_UTIL_CRC32_H__ */ |
| 96 | |