/* * Copyright (C) 2007 Red Hat, Inc. All rights reserved. * * This file is part of LVM2. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU Lesser General Public License v.2.1. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _LVM_UTIL_H #define _LVM_UTIL_H #include #define min(a, b) ({ typeof(a) _a = (a); \ typeof(b) _b = (b); \ (void) (&_a == &_b); \ _a < _b ? _a : _b; }) #define max(a, b) ({ typeof(a) _a = (a); \ typeof(b) _b = (b); \ (void) (&_a == &_b); \ _a > _b ? _a : _b; }) #define is_power_of_2(n) ((n) && !((n) & ((n) - 1))) #if defined(__clang__) || (defined(__GNUC__) && __GNUC__ >= 4 && __GNUC_MINOR__ >= 6) #define uninitialized_var(x) x #else #define uninitialized_var(x) x = x #endif /* * GCC 3.4 adds a __builtin_clz, which uses the count leading zeros (clz) * instruction on arches that have one. Provide a fallback using shifts * and comparisons for older compilers. */ #ifdef HAVE___BUILTIN_CLZ #define clz(x) __builtin_clz((x)) #else /* ifdef HAVE___BUILTIN_CLZ */ static unsigned _dm_clz(unsigned x) { int n; if ((int)x <= 0) return (~x >> 26) & 32; n = 1; if ((x >> 16) == 0) { n = n + 16; x = x << 16; } if ((x >> 24) == 0) { n = n + 8; x = x << 8; } if ((x >> 28) == 0) { n = n + 4; x = x << 4; } if ((x >> 30) == 0) { n = n + 2; x = x << 2; } n = n - (x >> 31); return n; } #define clz(x) _dm_clz((x)) #endif /* ifdef HAVE___BUILTIN_CLZ */ #ifdef HAVE___BUILTIN_CLZLL #define clzll(x) __builtin_clzll((x)) #else /* ifdef HAVE___BUILTIN_CLZ */ static unsigned _dm_clzll(unsigned long long x) { if (x <= 0xffffffff) return 32 + clz((unsigned) (x & 0xffffffff)); return clz(x >> 32); } #define clzll(x) _dm_clzll((x)) #endif /* ifdef HAVE___BUILTIN_CLZLL */ #define KERNEL_VERSION(major, minor, release) (((major) << 16) + ((minor) << 8) + (release)) /* Define some portable printing types */ #define PRIsize_t "zu" #define PRIssize_t "zd" #define PRIptrdiff_t "td" #define PRIpid_t PRId32 /* For convenience */ #define FMTsize_t "%" PRIsize_t #define FMTssize_t "%" PRIssize_t #define FMTptrdiff_t "%" PRIptrdiff_t #define FMTpid_t "%" PRIpid_t #define FMTd8 "%" PRId8 #define FMTd16 "%" PRId16 #define FMTd32 "%" PRId32 #define FMTd64 "%" PRId64 #define FMTi8 "%" PRIi8 #define FMTi16 "%" PRIi16 #define FMTi32 "%" PRIi32 #define FMTi64 "%" PRIi64 #define FMTo8 "%" PRIo8 #define FMTo16 "%" PRIo16 #define FMTo32 "%" PRIo32 #define FMTo64 "%" PRIo64 #define FMTu8 "%" PRIu8 #define FMTu16 "%" PRIu16 #define FMTu32 "%" PRIu32 #define FMTu64 "%" PRIu64 #define FMTx8 "%" PRIx8 #define FMTx16 "%" PRIx16 #define FMTx32 "%" PRIx32 #define FMTx64 "%" PRIx64 #define FMTVGID "%." DM_TO_STRING(ID_LEN) "s" #endif