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- /**
- * \file stdout
- * Functions and types for CRC checks.
- *
- * Generated on Tue Jun 30 21:35:13 2009,
- * by pycrc v0.7.1, http://www.tty1.net/pycrc/
- * using the configuration:
- * Width = 32
- * Poly = 0x04c11db7
- * XorIn = 0xffffffff
- * ReflectIn = True
- * XorOut = 0xffffffff
- * ReflectOut = True
- * Algorithm = bit-by-bit-fast
- * Direct = True
- *****************************************************************************/
- #include <stdint.h>
- #include "crc32.h"
- /**
- * Reflect all bits of a \a data word of \a data_len bytes.
- *
- * \param data The data word to be reflected.
- * \param data_len The width of \a data expressed in number of bits.
- * \return The reflected data.
- *****************************************************************************/
- long crc_reflect(long data, size_t data_len)
- {
- unsigned int i;
- long ret;
- ret = data & 0x01;
- for (i = 1; i < data_len; i++)
- {
- data >>= 1;
- ret = (ret << 1) | (data & 0x01);
- }
- return ret;
- }
- /**
- * Update the crc value with new data.
- *
- * \param crc The current crc value.
- * \param data Pointer to a buffer of \a data_len bytes.
- * \param data_len Number of bytes in the \a data buffer.
- * \return The updated crc value.
- *****************************************************************************/
- crc_t crc_update(crc_t crc, const unsigned char *data, size_t data_len)
- {
- unsigned int i;
- uint8_t bit;
- unsigned char c;
- while (data_len--) {
- c = *data++;
- for (i = 0x01; i & 0xff; i <<= 1) {
- bit = ((crc & 0x80000000) ? 1 : 0);
- if (c & i) {
- bit ^= 1;
- }
- crc <<= 1;
- if (bit) {
- crc ^= 0x04c11db7;
- }
- }
- crc &= 0xffffffff;
- }
- return crc & 0xffffffff;
- }
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