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MentOS/libc/inc/sys/bitops.h
T
Enrico Fraccaroli (Galfurian) 30e01ba560 Update version
2024-01-17 13:49:48 +01:00

51 lines
2.7 KiB
C

/// @file bitops.h
/// @brief Bitmasks functions.
/// @copyright (c) 2014-2024 This file is distributed under the MIT License.
/// See LICENSE.md for details.
#pragma once
#define bit_set(V, B) ((V) | (1U << (B))) ///< Sets the given bit.
#define bit_clear(V, B) ((V) & ~(1U << (B))) ///< Clears the given bit.
#define bit_flip(V, B) ((V) ^ (1U << (B))) ///< Flips the given bit.
#define bit_check(V, B) ((V) & (1U << (B))) ///< Checks if the given bit is 1.
#define bit_toggle(V, B, C) ((C) ? bit_set(V, B) : bit_clear(V, B)) ///< Sets the given bit based on control bit C.
#define bit_set_assign(V, B) ((V) |= (1U << (B))) ///< Sets the given bit, permanently.
#define bit_clear_assign(V, B) ((V) &= ~(1U << (B))) ///< Clears the given bit, permanently.
#define bit_flip_assign(V, B) ((V) ^= (1U << (B))) ///< Flips the given bit, permanently.
#define bit_toggle_assign(V, B, C) ((C) ? bit_set_assign(V, B) : bit_clear_assign(V, B)) ///< Sets the given bit based on control bit C.
#define bitmask_set(V, M) ((V) | (M)) ///< Sets the bits identified by the mask.
#define bitmask_clear(V, M) ((V) & ~(M)) ///< Clears the bits identified by the mask.
#define bitmask_flip(V, M) ((V) ^ (M)) ///< Flips the bits identified by the mask.
#define bitmask_check(V, M) ((V) & (M)) ///< Checks if the bits identified by the mask are all 1.
#define bitmask_set_assign(V, M) ((V) |= (M)) ///< Sets the bits identified by the mask, permanently.
#define bitmask_clear_assign(V, M) ((V) &= ~(M)) ///< Clears the bits identified by the mask, permanently.
#define bitmask_flip_assign(V, M) ((V) ^= (M)) ///< Flips the bits identified by the mask, permanently.
/// @brief Finds the first bit at zero, starting from the less significative bit.
/// @param value the value we need to analyze.
/// @return the position of the first zero bit.
static inline int find_first_zero(unsigned long value)
{
for (int i = 0; i < 32; ++i) {
if (!bit_check(value, i)) {
return i;
}
}
return 0;
}
/// @brief Finds the first bit not zero, starting from the less significative bit.
/// @param value the value we need to analyze.
/// @return the position of the first non-zero bit.
static inline int find_first_non_zero(unsigned long value)
{
for (int i = 0; i < 32; ++i) {
if (bit_check(value, i)) {
return i;
}
}
return 0;
}