math.h

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#ifndef UTILS_MATH_H
#define UTILS_MATH_H
 
#include <kernel/types.h>
 
#define MAX(_x, _y)                    \
    ({                                 \
        __typeof__(_x) _max1 = (_x);   \
        __typeof__(_y) _max2 = (_y);   \
        _max1 > _max2 ? _max1 : _max2; \
    })
 
#define MIN(_x, _y)                    \
    ({                                 \
        __typeof__(_x) _max1 = (_x);   \
        __typeof__(_y) _max2 = (_y);   \
        _max1 < _max2 ? _max1 : _max2; \
    })
 
#define ABS(_x)                     \
    ({                              \
        __typeof__(_x) _tmp = (_x); \
        _tmp < 0 ? -_tmp : _tmp;    \
    })
 
#define is_power_of_2(_x) (_x != 0 && ((_x & (_x - 1)) == 0))
 
#define __align_mask(_value, _power) ((__typeof__(_value))((_power)-1))
 
#define align_up(_value, _power) \
    ((((_value)-1) | __align_mask(_value, _power)) + 1)
 
#define align_down(_value, _power) ((_value) & ~__align_mask(_value, _power))
 
#define is_aligned(_value, _alignment) (!((_value) % (_alignment)))
 
#define align_down_ptr(_ptr, _power) ((void *)align_down((vaddr_t)_ptr, _power))
#define align_up_ptr(_ptr, _power) ((void *)align_up((vaddr_t)_ptr, _power))
#define is_aligned_ptr(_ptr, _alignment) is_aligned((vaddr_t)_ptr, _alignment)
 
static inline u32 round_up(u32 value, u32 alignment)
{
    if (alignment == 0)
        return value;
 
    u32 offset = value % alignment;
    if (offset)
        value += alignment - offset; // WARNING: Offset can occur here!
 
    return value;
}
 
static inline u32 round_down(u32 value, u32 alignment)
{
    if (alignment == 0)
        return value;
 
    return value - (value % alignment);
}
 
#endif /* UTILS_MATH_H */