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+#ifndef ucoo_utils_crc_hh
+#define ucoo_utils_crc_hh
+// ucoolib - Microcontroller object oriented library. {{{
+//
+// Copyright (C) 2013 Nicolas Schodet
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+//
+// }}}
+#include "ucoo/common.hh"
+
+/// Please read "A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS",
+/// http://www.ross.net/crc/download/crc_v3.txt
+
+namespace ucoo {
+
+/// Dallas/Maxim iButton 8bit CRC.
+/// Polynomial: x^8 + x^5 + x^4 + 1
+/// Initial value: 0
+static inline uint8_t
+crc8_update (uint8_t crc, uint8_t data)
+{
+ uint8_t i;
+ crc = crc ^ data;
+ for (i = 0; i < 8; i++)
+ {
+ if (crc & 0x01)
+ crc = (crc >> 1) ^ 0x8C;
+ else
+ crc >>= 1;
+ }
+ return crc;
+}
+
+uint8_t
+crc8_compute (const uint8_t *data, int size);
+
+/// Name : "CRC-32"
+/// Width : 32
+/// Poly : 04C11DB7
+/// Init : FFFFFFFF
+/// RefIn : True
+/// RefOut : True
+/// XorOut : FFFFFFFF
+/// Check : CBF43926
+uint32_t
+crc32_update (uint32_t crc, uint8_t data);
+
+uint32_t
+crc32_compute (const uint8_t *data, int size);
+
+} // namespace ucoo
+
+#endif // ucoo_utils_crc_hh