1 /* 2 * The UCW Library -- Miscellaneous Functions 3 * 4 * (c) 1997--2014 Martin Mares <mj@ucw.cz> 5 * (c) 2005--2014 Tomas Valla <tom@ucw.cz> 6 * (c) 2006 Robert Spalek <robert@ucw.cz> 7 * (c) 2007 Pavel Charvat <pchar@ucw.cz> 8 * 9 * SPDX-License-Identifier: LGPL-2.1-or-later 10 * Source: https://www.ucw.cz/libucw/ 11 */ 12 13 #ifndef _UCW_LIB_H 14 #define _UCW_LIB_H 15 16 #include <stdarg.h> 17 #include <stdbool.h> 18 #include <stdlib.h> 19 20 #ifdef CONFIG_UCW_CLEAN_ABI 21 #define assert_failed ucw_assert_failed 22 #define assert_failed_msg ucw_assert_failed_msg 23 #define assert_failed_noinfo ucw_assert_failed_noinfo 24 #define big_alloc ucw_big_alloc 25 #define big_alloc_zero ucw_big_alloc_zero 26 #define big_free ucw_big_free 27 #define die ucw_die 28 #define log_die_hook ucw_log_die_hook 29 #define log_file ucw_log_file 30 #define log_fork ucw_log_fork 31 #define log_init ucw_log_init 32 #define log_pid ucw_log_pid 33 #define log_title ucw_log_title 34 #define msg ucw_msg 35 #define page_alloc ucw_page_alloc 36 #define page_alloc_zero ucw_page_alloc_zero 37 #define page_free ucw_page_free 38 #define page_realloc ucw_page_realloc 39 #define random_max ucw_random_max 40 #define random_max_u64 ucw_random_max_u64 41 #define random_u32 ucw_random_u32 42 #define random_u64 ucw_random_u64 43 #define vdie ucw_vdie 44 #define vmsg ucw_vmsg 45 #define xfree ucw_xfree 46 #define xmalloc ucw_xmalloc 47 #define xmalloc_zero ucw_xmalloc_zero 48 #define xrealloc ucw_xrealloc 49 #define xstrdup ucw_xstrdup 50 #endif 51 52 /*** === Macros for handling structures, offsets and alignment ***/ 53 54 #define CHECK_PTR_TYPE(x, type) ((x)-(type)(x) + (type)(x)) /** Check that a pointer @x is of type @type. Fail compilation if not. **/ 55 #define PTR_TO(s, i) &((s*)0)->i /** Return OFFSETOF() in form of a pointer. **/ 56 #define OFFSETOF(s, i) ((uint)offsetof(s, i)) /** Offset of item @i from the start of structure @s **/ 57 #define SKIP_BACK(s, i, p) ((s *)((char *)p - OFFSETOF(s, i))) /** Given a pointer @p to item @i of structure @s, return a pointer to the start of the struct. **/ 58 59 /** Align an integer @s to the nearest higher multiple of @a (which should be a power of two) **/ 60 #define ALIGN_TO(s, a) (((s)+a-1)&~(a-1)) 61 62 /** Align a pointer @p to the nearest higher multiple of @s. **/ 63 #define ALIGN_PTR(p, s) ((uintptr_t)(p) % (s) ? (typeof(p))((uintptr_t)(p) + (s) - (uintptr_t)(p) % (s)) : (p)) 64 65 #define UNALIGNED_PART(ptr, type) (((uintptr_t) (ptr)) % sizeof(type)) 66 67 /*** === Other utility macros ***/ 68 69 #define MIN(a,b) (((a)<(b))?(a):(b)) /** Minimum of two numbers **/ 70 #define MAX(a,b) (((a)>(b))?(a):(b)) /** Maximum of two numbers **/ 71 #define CLAMP(x,min,max) ({ typeof(x) _t=x; (_t < min) ? min : (_t > max) ? max : _t; }) /** Clip a number @x to interval [@min,@max] **/ 72 #define ABS(x) ((x) < 0 ? -(x) : (x)) /** Absolute value **/ 73 #define ARRAY_SIZE(a) (sizeof(a)/sizeof(*(a))) /** The number of elements of an array **/ 74 #define STRINGIFY(x) #x /** Convert macro parameter to a string **/ 75 #define STRINGIFY_EXPANDED(x) STRINGIFY(x) /** Convert an expanded macro parameter to a string **/ 76 #define GLUE(x,y) x##y /** Glue two tokens together **/ 77 #define GLUE_(x,y) x##_##y /** Glue two tokens together, separating them by an underscore **/ 78 79 #define COMPARE(x,y) do { if ((x)<(y)) return -1; if ((x)>(y)) return 1; } while(0) /** Numeric comparison function for qsort() **/ 80 #define REV_COMPARE(x,y) COMPARE(y,x) /** Reverse numeric comparison **/ 81 #define COMPARE_LT(x,y) do { if ((x)<(y)) return 1; if ((x)>(y)) return 0; } while(0) 82 #define COMPARE_GT(x,y) COMPARE_LT(y,x) 83 84 #define ROL(x, bits) (((x) << (bits)) | ((uint)(x) >> (sizeof(uint)*8 - (bits)))) /** Bitwise rotation of an unsigned int to the left **/ 85 #define ROR(x, bits) (((uint)(x) >> (bits)) | ((x) << (sizeof(uint)*8 - (bits)))) /** Bitwise rotation of an unsigned int to the right **/ 86 87 /*** === Shortcuts for GCC Extensions ***/ 88 89 #ifdef __GNUC__ 90 91 #include "ccan/compiler/compiler.h" 92 #define FORMAT_CHECK(x,y,z) __attribute__((format(x,y,z))) /** Checking of printf-like format strings **/ 93 #define likely(x) __builtin_expect((x),1) /** Use `if (likely(@x))` if @x is almost always true **/ 94 #define unlikely(x) __builtin_expect((x),0) /** Use `if (unlikely(@x))` to hint that @x is almost always false **/ 95 96 #if __GNUC__ >= 4 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3 97 #define ALWAYS_INLINE inline __attribute__((always_inline)) /** Forcibly inline **/ 98 #define NO_INLINE __attribute__((noinline)) /** Forcibly uninline **/ 99 #else 100 #define ALWAYS_INLINE inline 101 #endif 102 103 #if __GNUC__ >= 4 104 #define LIKE_MALLOC __attribute__((malloc)) /** Function returns a "new" pointer **/ 105 #define SENTINEL_CHECK __attribute__((sentinel)) /** The last argument must be NULL **/ 106 #else 107 #define LIKE_MALLOC 108 #define SENTINEL_CHECK 109 #endif 110 111 #else 112 #error This program requires the GNU C compiler. 113 #endif 114 115 /*** 116 * [[logging]] 117 * 118 * === Basic logging functions (see <<log:,Logging>> and <ucw/log.h> for more) 119 ***/ 120 121 #define DBG(x, ...) do { } while(0) 122 #define DBG_SPOT do { } while(0) 123 #define ASSERT(x) 124 125 #endif 126