/* See the end of this file for copyright and license terms. */

#pragma once

#include <gay/cdefs.h>

/**
 * @brief Get the number of elements in a statically allocated array.
 *
 * @param a The array
 * @returns The number of elements
 */
#define ARRAY_SIZE(a) ( sizeof(a) / sizeof(a[0]) )

#define abs(x) ({		\
	typeof(x) __x = (x);	\
	__x < 0 ? -__x : __x;	\
})

#define max(a, b) ({		\
	typeof(a) __a = (a);	\
	typeof(b) __b = (b);	\
	__a > __b ? __a : __b;	\
})

#define min(a, b) ({		\
	typeof(a) __a = (a);	\
	typeof(b) __b = (b);	\
	__a < __b ? __a : __b;	\
})

/**
 * @brief Cast a pointer to a struct member out to the containing structure.
 *
 * @param ptr Pointer to the struct member
 * @param type Type of the containing structure
 * @param member Name of the member within the containing structure
 * @returns Pointer to the containing structure
 */
#define container_of(ptr, type, member) \
	((type *)( (void *)(ptr) - offsetof(type, member) ))

/**
 * @brief Do an evil raw cast.
 *
 * @param type Type to cast to
 * @param expr Expression to cast
 * @returns The raw value of `expr`, cast to `type`
 */
#define raw_cast(type, expr) ({		\
	typeof(expr) __expr = (expr);	\
	*(type *)&__expr;		\
})

/**
 * @brief Align `ptr` such that `ptr % n == 0`.
 *
 * @param ptr Pointer to align
 * @param log The log2 of the alignment.  If negative, the pointer will be
 *	aligned to the next lower address, otherwise to the next higher one.
 * @returns The aligned pointer
 */
void *ptr_align(void *ptr, int log);

/*
 * This file is part of GayBSD.
 * Copyright (c) 2021 fef <owo@fef.moe>.
 *
 * GayBSD is nonviolent software: you may only use, redistribute, and/or
 * modify it under the terms of the Cooperative Nonviolent Public License
 * (CNPL) as found in the LICENSE file in the source code root directory
 * or at <https://git.pixie.town/thufie/npl-builder>; either version 7
 * of the license, or (at your option) any later version.
 *
 * GayBSD comes with ABSOLUTELY NO WARRANTY, to the extent
 * permitted by applicable law.  See the CNPL for details.
 */