diff --git a/src/crc.c b/src/crc.c new file mode 100644 index 00000000..058b1529 --- /dev/null +++ b/src/crc.c @@ -0,0 +1,43 @@ +/* + * This file is part of the libsigrok project. + * + * Copyright (C) 2015 Aurelien Jacobs + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include "libsigrok-internal.h" + +SR_PRIV uint16_t sr_crc16(uint16_t crc, const uint8_t *buffer, int len) +{ + int i; + + if (!buffer || len < 0) + return crc; + + while (len--) { + crc ^= *buffer++; + for (i = 0; i < 8; i++) { + int carry = crc & 1; + crc >>= 1; + if (carry) + crc ^= 0xA001; + } + } + + return crc; +}