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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#pragma once
/**
* @file sys/param.h
* @brief Various macros.
*/
#include <endian.h>
#include <limits.h>
#include <linux/param.h>
#include <sys/cdefs.h>
/** The unit of `st_blocks` in `struct stat`. */
#define DEV_BSIZE 512
/** A historical name for PATH_MAX. */
#define MAXPATHLEN PATH_MAX
#define MAXSYMLINKS 8
#ifndef howmany
#define howmany(x, y) (((x)+((y)-1))/(y))
#endif
#define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
/**
* Returns true if the binary representation of the argument is all zeros
* or has exactly one bit set. Contrary to the macro name, this macro
* DOES NOT determine if the provided value is a power of 2. In particular,
* this function falsely returns true for powerof2(0) and some negative
* numbers.
*/
#define powerof2(x) \
({ \
__typeof__(x) _x = (x); \
__typeof__(x) _x2; \
__builtin_add_overflow(_x, -1, &_x2) ? 1 : ((_x2 & _x) == 0); \
})
/** Returns the lesser of its two arguments. */
#define MIN(a,b) (((a)<(b))?(a):(b))
/** Returns the greater of its two arguments. */
#define MAX(a,b) (((a)>(b))?(a):(b))