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#ifndef BITOPS_H
#define BITOPS_H
#include "string.h" /* due to memset */
/* determines if bit number "bit_nb" is set in array "arr" */
#define IS_BIT_SET(arr, bit_nb) (((unsigned char*) arr)[(bit_nb) >> 3] & \
(((unsigned char) 1) << ((bit_nb) & 7)))
/* determines if bit number "bit_nb" is set in array "arr" */
#define IS_BIT_CLEARED(arr, bit_nb) (! IS_BIT_SET(arr, bit_nb))
/* resets bit "bit_nb" in array "arr" */
#define RESET_BIT(arr, bit_nb) (((unsigned char*) arr)[(bit_nb) >> 3] &= ~(((unsigned char) 1) << ((bit_nb) & 7)))
/* sets bit "bit_nb" in array "arr" */
#define SET_BIT(arr, bit_nb) (((unsigned char*) arr)[(bit_nb) >> 3] |= ((unsigned char) 1) << ((bit_nb) & 7))
/* set the first nb_bits in array arr */
inline void SET_ALL_BITS(unsigned char* arr, unsigned long nb_bits)
{
memset(arr, 255, nb_bits >> 3);
if(nb_bits & 7) {
arr[nb_bits >> 3] |= ((unsigned char) 255) >> (8 - (nb_bits & 7));
}
}
/* reset the first nb_bits in array arr */
inline void RESET_ALL_BITS(unsigned char* arr, unsigned long nb_bits)
{
memset(arr, 0, nb_bits >> 3);
if(nb_bits & 7) {
arr[nb_bits >> 3] &= ((unsigned char) 255) << (nb_bits & 7);
}
}
#endif
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