arduino-esp32/tools/sdk/include/coap/bits.h

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/*
* bits.h -- bit vector manipulation
*
* Copyright (C) 2010-2011 Olaf Bergmann <bergmann@tzi.org>
*
* This file is part of the CoAP library libcoap. Please see README for terms
* of use.
*/
/**
* @file bits.h
* @brief Bit vector manipulation
*/
#ifndef _COAP_BITS_H_
#define _COAP_BITS_H_
#include <stdint.h>
/**
* Sets the bit @p bit in bit-vector @p vec. This function returns @c 1 if bit
* was set or @c -1 on error (i.e. when the given bit does not fit in the
* vector).
*
* @param vec The bit-vector to change.
* @param size The size of @p vec in bytes.
* @param bit The bit to set in @p vec.
*
* @return @c -1 if @p bit does not fit into @p vec, @c 1 otherwise.
*/
inline static int
bits_setb(uint8_t *vec, size_t size, uint8_t bit) {
if (size <= (bit >> 3))
return -1;
*(vec + (bit >> 3)) |= (uint8_t)(1 << (bit & 0x07));
return 1;
}
/**
* Clears the bit @p bit from bit-vector @p vec. This function returns @c 1 if
* bit was cleared or @c -1 on error (i.e. when the given bit does not fit in
* the vector).
*
* @param vec The bit-vector to change.
* @param size The size of @p vec in bytes.
* @param bit The bit to clear from @p vec.
*
* @return @c -1 if @p bit does not fit into @p vec, @c 1 otherwise.
*/
inline static int
bits_clrb(uint8_t *vec, size_t size, uint8_t bit) {
if (size <= (bit >> 3))
return -1;
*(vec + (bit >> 3)) &= (uint8_t)(~(1 << (bit & 0x07)));
return 1;
}
/**
* Gets the status of bit @p bit from bit-vector @p vec. This function returns
* @c 1 if the bit is set, @c 0 otherwise (even in case of an error).
*
* @param vec The bit-vector to read from.
* @param size The size of @p vec in bytes.
* @param bit The bit to get from @p vec.
*
* @return @c 1 if the bit is set, @c 0 otherwise.
*/
inline static int
bits_getb(const uint8_t *vec, size_t size, uint8_t bit) {
if (size <= (bit >> 3))
return -1;
return (*(vec + (bit >> 3)) & (1 << (bit & 0x07))) != 0;
}
#endif /* _COAP_BITS_H_ */