| /* |
| * 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)) |
