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Diffstat (limited to 'LIDAR/sdk/src/sl_crc.cpp')
| -rw-r--r-- | LIDAR/sdk/src/sl_crc.cpp | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/LIDAR/sdk/src/sl_crc.cpp b/LIDAR/sdk/src/sl_crc.cpp new file mode 100644 index 0000000..49d7844 --- /dev/null +++ b/LIDAR/sdk/src/sl_crc.cpp @@ -0,0 +1,102 @@ +/* + * Slamtec LIDAR SDK + * + * Copyright (c) 2014 - 2020 Shanghai Slamtec Co., Ltd. + * http://www.slamtec.com + * + */ + /* + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, + * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#include "sl_crc.h" + +namespace sl {namespace crc32 { + + static sl_u32 table[256];//crc32_table + sl_u32 bitrev(sl_u32 input, sl_u16 bw) + { + sl_u16 i; + sl_u32 var; + var = 0; + for (i = 0; i < bw; i++) { + if (input & 0x01) { + var |= 1 << (bw - 1 - i); + } + input >>= 1; + } + return var; + } + + void init(sl_u32 poly) + { + sl_u16 i; + sl_u16 j; + sl_u32 c; + + poly = bitrev(poly, 32); + for (i = 0; i < 256; i++) { + c = i; + for (j = 0; j < 8; j++) { + if (c & 1) + c = poly ^ (c >> 1); + else + c = c >> 1; + } + table[i] = c; + } + } + + sl_u32 cal(sl_u32 crc, void* input, sl_u16 len) + { + sl_u16 i; + sl_u8 index; + sl_u8* pch; + pch = (unsigned char*)input; + sl_u8 leftBytes = 4 - (len & 0x3); + + for (i = 0; i < len; i++) { + index = (unsigned char)(crc^*pch); + crc = (crc >> 8) ^ table[index]; + pch++; + } + + for (i = 0; i < leftBytes; i++) {//zero padding + index = (unsigned char)(crc ^ 0); + crc = (crc >> 8) ^ table[index]; + } + return crc ^ 0xffffffff; + } + + sl_result getResult(sl_u8 *ptr, sl_u32 len) + { + static sl_u8 tmp; + if (tmp != 1) { + init(0x4C11DB7); + tmp = 1; + } + + return cal(0xFFFFFFFF, ptr, len); + } +}}
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