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git.ipfire.org Git - thirdparty/systemd.git/blob - src/basic/macro.h
1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
6 This file is part of systemd.
8 Copyright 2010 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
25 #include <sys/param.h>
26 #include <sys/types.h>
31 #define _printf_(a,b) __attribute__ ((format (printf, a, b)))
32 #define _alloc_(...) __attribute__ ((alloc_size(__VA_ARGS__)))
33 #define _sentinel_ __attribute__ ((sentinel))
34 #define _unused_ __attribute__ ((unused))
35 #define _destructor_ __attribute__ ((destructor))
36 #define _pure_ __attribute__ ((pure))
37 #define _const_ __attribute__ ((const))
38 #define _deprecated_ __attribute__ ((deprecated))
39 #define _packed_ __attribute__ ((packed))
40 #define _malloc_ __attribute__ ((malloc))
41 #define _weak_ __attribute__ ((weak))
42 #define _likely_(x) (__builtin_expect(!!(x),1))
43 #define _unlikely_(x) (__builtin_expect(!!(x),0))
44 #define _public_ __attribute__ ((visibility("default")))
45 #define _hidden_ __attribute__ ((visibility("hidden")))
46 #define _weakref_(x) __attribute__((weakref(#x)))
47 #define _alignas_(x) __attribute__((aligned(__alignof(x))))
48 #define _cleanup_(x) __attribute__((cleanup(x)))
50 /* Temporarily disable some warnings */
51 #define DISABLE_WARNING_DECLARATION_AFTER_STATEMENT \
52 _Pragma("GCC diagnostic push"); \
53 _Pragma("GCC diagnostic ignored \"-Wdeclaration-after-statement\"")
55 #define DISABLE_WARNING_FORMAT_NONLITERAL \
56 _Pragma("GCC diagnostic push"); \
57 _Pragma("GCC diagnostic ignored \"-Wformat-nonliteral\"")
59 #define DISABLE_WARNING_MISSING_PROTOTYPES \
60 _Pragma("GCC diagnostic push"); \
61 _Pragma("GCC diagnostic ignored \"-Wmissing-prototypes\"")
63 #define DISABLE_WARNING_NONNULL \
64 _Pragma("GCC diagnostic push"); \
65 _Pragma("GCC diagnostic ignored \"-Wnonnull\"")
67 #define DISABLE_WARNING_SHADOW \
68 _Pragma("GCC diagnostic push"); \
69 _Pragma("GCC diagnostic ignored \"-Wshadow\"")
71 #define DISABLE_WARNING_INCOMPATIBLE_POINTER_TYPES \
72 _Pragma("GCC diagnostic push"); \
73 _Pragma("GCC diagnostic ignored \"-Wincompatible-pointer-types\"")
75 #define REENABLE_WARNING \
76 _Pragma("GCC diagnostic pop")
78 /* automake test harness */
79 #define EXIT_TEST_SKIP 77
81 #define XSTRINGIFY(x) #x
82 #define STRINGIFY(x) XSTRINGIFY(x)
84 #define XCONCATENATE(x, y) x ## y
85 #define CONCATENATE(x, y) XCONCATENATE(x, y)
87 #define UNIQ_T(x, uniq) CONCATENATE(__unique_prefix_, CONCATENATE(x, uniq))
88 #define UNIQ __COUNTER__
92 #define ALIGN4(l) (((l) + 3) & ~3)
93 #define ALIGN8(l) (((l) + 7) & ~7)
95 #if __SIZEOF_POINTER__ == 8
96 #define ALIGN(l) ALIGN8(l)
97 #elif __SIZEOF_POINTER__ == 4
98 #define ALIGN(l) ALIGN4(l)
100 #error "Wut? Pointers are neither 4 nor 8 bytes long?"
103 #define ALIGN_PTR(p) ((void*) ALIGN((unsigned long) (p)))
104 #define ALIGN4_PTR(p) ((void*) ALIGN4((unsigned long) (p)))
105 #define ALIGN8_PTR(p) ((void*) ALIGN8((unsigned long) (p)))
107 static inline size_t ALIGN_TO(size_t l
, size_t ali
) {
108 return ((l
+ ali
- 1) & ~(ali
- 1));
111 #define ALIGN_TO_PTR(p, ali) ((void*) ALIGN_TO((unsigned long) (p), (ali)))
113 /* align to next higher power-of-2 (except for: 0 => 0, overflow => 0) */
114 static inline unsigned long ALIGN_POWER2(unsigned long u
) {
115 /* clz(0) is undefined */
119 /* left-shift overflow is undefined */
120 if (__builtin_clzl(u
- 1UL) < 1)
123 return 1UL << (sizeof(u
) * 8 - __builtin_clzl(u
- 1UL));
126 #define ELEMENTSOF(x) \
127 __extension__ (__builtin_choose_expr( \
128 !__builtin_types_compatible_p(typeof(x), typeof(&*(x))), \
129 sizeof(x)/sizeof((x)[0]), \
132 * container_of - cast a member of a structure out to the containing structure
133 * @ptr: the pointer to the member.
134 * @type: the type of the container struct this is embedded in.
135 * @member: the name of the member within the struct.
137 #define container_of(ptr, type, member) __container_of(UNIQ, (ptr), type, member)
138 #define __container_of(uniq, ptr, type, member) \
140 const typeof( ((type*)0)->member ) *UNIQ_T(A, uniq) = (ptr); \
141 (type*)( (char *)UNIQ_T(A, uniq) - offsetof(type,member) ); \
145 #define MAX(a, b) __MAX(UNIQ, (a), UNIQ, (b))
146 #define __MAX(aq, a, bq, b) \
148 const typeof(a) UNIQ_T(A, aq) = (a); \
149 const typeof(b) UNIQ_T(B, bq) = (b); \
150 UNIQ_T(A,aq) > UNIQ_T(B,bq) ? UNIQ_T(A,aq) : UNIQ_T(B,bq); \
153 /* evaluates to (void) if _A or _B are not constant or of different types */
154 #define CONST_MAX(_A, _B) \
155 __extension__ (__builtin_choose_expr( \
156 __builtin_constant_p(_A) && \
157 __builtin_constant_p(_B) && \
158 __builtin_types_compatible_p(typeof(_A), typeof(_B)), \
159 ((_A) > (_B)) ? (_A) : (_B), \
162 /* takes two types and returns the size of the larger one */
163 #define MAXSIZE(A, B) (sizeof(union _packed_ { typeof(A) a; typeof(B) b; }))
165 #define MAX3(x,y,z) \
167 const typeof(x) _c = MAX(x,y); \
172 #define MIN(a, b) __MIN(UNIQ, (a), UNIQ, (b))
173 #define __MIN(aq, a, bq, b) \
175 const typeof(a) UNIQ_T(A, aq) = (a); \
176 const typeof(b) UNIQ_T(B, bq) = (b); \
177 UNIQ_T(A,aq) < UNIQ_T(B,bq) ? UNIQ_T(A,aq) : UNIQ_T(B,bq); \
180 #define MIN3(x,y,z) \
182 const typeof(x) _c = MIN(x,y); \
186 #define LESS_BY(a, b) __LESS_BY(UNIQ, (a), UNIQ, (b))
187 #define __LESS_BY(aq, a, bq, b) \
189 const typeof(a) UNIQ_T(A, aq) = (a); \
190 const typeof(b) UNIQ_T(B, bq) = (b); \
191 UNIQ_T(A,aq) > UNIQ_T(B,bq) ? UNIQ_T(A,aq) - UNIQ_T(B,bq) : 0; \
195 #define CLAMP(x, low, high) __CLAMP(UNIQ, (x), UNIQ, (low), UNIQ, (high))
196 #define __CLAMP(xq, x, lowq, low, highq, high) \
198 const typeof(x) UNIQ_T(X,xq) = (x); \
199 const typeof(low) UNIQ_T(LOW,lowq) = (low); \
200 const typeof(high) UNIQ_T(HIGH,highq) = (high); \
201 UNIQ_T(X,xq) > UNIQ_T(HIGH,highq) ? \
202 UNIQ_T(HIGH,highq) : \
203 UNIQ_T(X,xq) < UNIQ_T(LOW,lowq) ? \
208 /* [(x + y - 1) / y] suffers from an integer overflow, even though the
209 * computation should be possible in the given type. Therefore, we use
210 * [x / y + !!(x % y)]. Note that on "Real CPUs" a division returns both the
211 * quotient and the remainder, so both should be equally fast. */
212 #define DIV_ROUND_UP(_x, _y) \
214 const typeof(_x) __x = (_x); \
215 const typeof(_y) __y = (_y); \
216 (__x / __y + !!(__x % __y)); \
219 #define assert_message_se(expr, message) \
221 if (_unlikely_(!(expr))) \
222 log_assert_failed(message, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
225 #define assert_se(expr) assert_message_se(expr, #expr)
227 /* We override the glibc assert() here. */
230 #define assert(expr) do {} while(false)
232 #define assert(expr) assert_message_se(expr, #expr)
235 #define assert_not_reached(t) \
237 log_assert_failed_unreachable(t, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
240 #if defined(static_assert)
241 /* static_assert() is sometimes defined in a way that trips up
242 * -Wdeclaration-after-statement, hence let's temporarily turn off
243 * this warning around it. */
244 #define assert_cc(expr) \
245 DISABLE_WARNING_DECLARATION_AFTER_STATEMENT; \
246 static_assert(expr, #expr); \
249 #define assert_cc(expr) \
250 DISABLE_WARNING_DECLARATION_AFTER_STATEMENT; \
251 struct CONCATENATE(_assert_struct_, __COUNTER__) { \
252 char x[(expr) ? 0 : -1]; \
257 #define assert_log(expr, message) ((_likely_(expr)) \
259 : (log_assert_failed_return(message, __FILE__, __LINE__, __PRETTY_FUNCTION__), false))
261 #define assert_return(expr, r) \
263 if (!assert_log(expr, #expr)) \
267 #define assert_return_errno(expr, r, err) \
269 if (!assert_log(expr, #expr)) { \
275 #define PTR_TO_INT(p) ((int) ((intptr_t) (p)))
276 #define INT_TO_PTR(u) ((void *) ((intptr_t) (u)))
277 #define PTR_TO_UINT(p) ((unsigned int) ((uintptr_t) (p)))
278 #define UINT_TO_PTR(u) ((void *) ((uintptr_t) (u)))
280 #define PTR_TO_LONG(p) ((long) ((intptr_t) (p)))
281 #define LONG_TO_PTR(u) ((void *) ((intptr_t) (u)))
282 #define PTR_TO_ULONG(p) ((unsigned long) ((uintptr_t) (p)))
283 #define ULONG_TO_PTR(u) ((void *) ((uintptr_t) (u)))
285 #define PTR_TO_INT32(p) ((int32_t) ((intptr_t) (p)))
286 #define INT32_TO_PTR(u) ((void *) ((intptr_t) (u)))
287 #define PTR_TO_UINT32(p) ((uint32_t) ((uintptr_t) (p)))
288 #define UINT32_TO_PTR(u) ((void *) ((uintptr_t) (u)))
290 #define PTR_TO_INT64(p) ((int64_t) ((intptr_t) (p)))
291 #define INT64_TO_PTR(u) ((void *) ((intptr_t) (u)))
292 #define PTR_TO_UINT64(p) ((uint64_t) ((uintptr_t) (p)))
293 #define UINT64_TO_PTR(u) ((void *) ((uintptr_t) (u)))
295 #define PTR_TO_SIZE(p) ((size_t) ((uintptr_t) (p)))
296 #define SIZE_TO_PTR(u) ((void *) ((uintptr_t) (u)))
298 #define PTR_TO_PID(p) ((pid_t) ((uintptr_t) p))
299 #define PID_TO_PTR(p) ((void*) ((uintptr_t) p))
301 #define memzero(x,l) (memset((x), 0, (l)))
302 #define zero(x) (memzero(&(x), sizeof(x)))
304 #define CHAR_TO_STR(x) ((char[2]) { x, 0 })
306 #define char_array_0(x) x[sizeof(x)-1] = 0;
308 #define IOVEC_SET_STRING(i, s) \
310 struct iovec *_i = &(i); \
311 char *_s = (char *)(s); \
313 _i->iov_len = strlen(_s); \
316 static inline size_t IOVEC_TOTAL_SIZE(const struct iovec
*i
, unsigned n
) {
320 for (j
= 0; j
< n
; j
++)
326 static inline size_t IOVEC_INCREMENT(struct iovec
*i
, unsigned n
, size_t k
) {
329 for (j
= 0; j
< n
; j
++) {
332 if (_unlikely_(k
<= 0))
335 sub
= MIN(i
[j
].iov_len
, k
);
337 i
[j
].iov_base
= (uint8_t*) i
[j
].iov_base
+ sub
;
344 #define VA_FORMAT_ADVANCE(format, ap) \
346 int _argtypes[128]; \
348 _k = parse_printf_format((format), ELEMENTSOF(_argtypes), _argtypes); \
349 assert(_k < ELEMENTSOF(_argtypes)); \
350 for (_i = 0; _i < _k; _i++) { \
351 if (_argtypes[_i] & PA_FLAG_PTR) { \
352 (void) va_arg(ap, void*); \
356 switch (_argtypes[_i]) { \
358 case PA_INT|PA_FLAG_SHORT: \
360 (void) va_arg(ap, int); \
362 case PA_INT|PA_FLAG_LONG: \
363 (void) va_arg(ap, long int); \
365 case PA_INT|PA_FLAG_LONG_LONG: \
366 (void) va_arg(ap, long long int); \
369 (void) va_arg(ap, wchar_t); \
374 (void) va_arg(ap, void*); \
378 (void) va_arg(ap, double); \
380 case PA_DOUBLE|PA_FLAG_LONG_DOUBLE: \
381 (void) va_arg(ap, long double); \
384 assert_not_reached("Unknown format string argument."); \
389 /* Because statfs.t_type can be int on some architectures, we have to cast
390 * the const magic to the type, otherwise the compiler warns about
391 * signed/unsigned comparison, because the magic can be 32 bit unsigned.
393 #define F_TYPE_EQUAL(a, b) (a == (typeof(a)) b)
395 /* Returns the number of chars needed to format variables of the
396 * specified type as a decimal string. Adds in extra space for a
397 * negative '-' prefix (hence works correctly on signed
398 * types). Includes space for the trailing NUL. */
399 #define DECIMAL_STR_MAX(type) \
400 (2+(sizeof(type) <= 1 ? 3 : \
401 sizeof(type) <= 2 ? 5 : \
402 sizeof(type) <= 4 ? 10 : \
403 sizeof(type) <= 8 ? 20 : sizeof(int[-2*(sizeof(type) > 8)])))
405 #define SET_FLAG(v, flag, b) \
406 (v) = (b) ? ((v) | (flag)) : ((v) & ~(flag))
408 #define IN_SET(x, y, ...) \
410 static const typeof(y) _array[] = { (y), __VA_ARGS__ }; \
411 const typeof(y) _x = (x); \
413 bool _found = false; \
414 for (_i = 0; _i < ELEMENTSOF(_array); _i++) \
415 if (_array[_i] == _x) { \
422 /* Return a nulstr for a standard cascade of configuration directories,
423 * suitable to pass to conf_files_list_nulstr or config_parse_many. */
424 #define CONF_DIRS_NULSTR(n) \
427 "/usr/local/lib/" n ".d\0" \
428 "/usr/lib/" n ".d\0" \
429 CONF_DIR_SPLIT_USR(n)
431 #ifdef HAVE_SPLIT_USR
432 #define CONF_DIR_SPLIT_USR(n) "/lib/" n ".d\0"
434 #define CONF_DIR_SPLIT_USR(n)
437 /* Define C11 thread_local attribute even on older gcc compiler
441 * Don't break on glibc < 2.16 that doesn't define __STDC_NO_THREADS__
442 * see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53769
444 #if __STDC_VERSION__ >= 201112L && !(defined(__STDC_NO_THREADS__) || (defined(__GNU_LIBRARY__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 16))
445 #define thread_local _Thread_local
447 #define thread_local __thread
451 /* Define C11 noreturn without <stdnoreturn.h> and even on older gcc
452 * compiler versions */
454 #if __STDC_VERSION__ >= 201112L
455 #define noreturn _Noreturn
457 #define noreturn __attribute__((noreturn))
461 #define MODE_INVALID ((mode_t) -1)
463 #define DEFINE_TRIVIAL_CLEANUP_FUNC(type, func) \
464 static inline void func##p(type *p) { \
468 struct __useless_struct_to_allow_trailing_semicolon__
470 #define CMSG_FOREACH(cmsg, mh) \
471 for ((cmsg) = CMSG_FIRSTHDR(mh); (cmsg); (cmsg) = CMSG_NXTHDR((mh), (cmsg)))