chiark / gitweb /
tree-wide: remove Lennart's copyright lines
[elogind.git] / src / basic / macro.h
1 /* SPDX-License-Identifier: LGPL-2.1+ */
2 #pragma once
3
4 #include <inttypes.h>
5 #include <stdbool.h>
6 #include <sys/param.h>
7 #include <sys/sysmacros.h>
8 #include <sys/types.h>
9
10 #define _printf_(a,b) __attribute__ ((format (printf, a, b)))
11 #ifdef __clang__
12 #  define _alloc_(...)
13 #else
14 #  define _alloc_(...) __attribute__ ((alloc_size(__VA_ARGS__)))
15 #endif
16 #define _sentinel_ __attribute__ ((sentinel))
17 #define _unused_ __attribute__ ((unused))
18 #define _destructor_ __attribute__ ((destructor))
19 #define _pure_ __attribute__ ((pure))
20 #define _const_ __attribute__ ((const))
21 #define _deprecated_ __attribute__ ((deprecated))
22 #define _packed_ __attribute__ ((packed))
23 #define _malloc_ __attribute__ ((malloc))
24 #define _weak_ __attribute__ ((weak))
25 #define _likely_(x) (__builtin_expect(!!(x),1))
26 #define _unlikely_(x) (__builtin_expect(!!(x),0))
27 #define _public_ __attribute__ ((visibility("default")))
28 #define _hidden_ __attribute__ ((visibility("hidden")))
29 #define _weakref_(x) __attribute__((weakref(#x)))
30 #define _alignas_(x) __attribute__((aligned(__alignof(x))))
31 #define _cleanup_(x) __attribute__((cleanup(x)))
32 #if __GNUC__ >= 7
33 #define _fallthrough_ __attribute__((fallthrough))
34 #else
35 #define _fallthrough_
36 #endif
37 /* Define C11 noreturn without <stdnoreturn.h> and even on older gcc
38  * compiler versions */
39 #ifndef _noreturn_
40 #if __STDC_VERSION__ >= 201112L
41 #define _noreturn_ _Noreturn
42 #else
43 #define _noreturn_ __attribute__((noreturn))
44 #endif
45 #endif
46
47 #if !defined(HAS_FEATURE_MEMORY_SANITIZER)
48 #  if defined(__has_feature)
49 #    if __has_feature(memory_sanitizer)
50 #      define HAS_FEATURE_MEMORY_SANITIZER 1
51 #    endif
52 #  endif
53 #  if !defined(HAS_FEATURE_MEMORY_SANITIZER)
54 #    define HAS_FEATURE_MEMORY_SANITIZER 0
55 #  endif
56 #endif
57
58 /* Temporarily disable some warnings */
59 #define DISABLE_WARNING_DECLARATION_AFTER_STATEMENT                     \
60         _Pragma("GCC diagnostic push");                                 \
61         _Pragma("GCC diagnostic ignored \"-Wdeclaration-after-statement\"")
62
63 #define DISABLE_WARNING_FORMAT_NONLITERAL                               \
64         _Pragma("GCC diagnostic push");                                 \
65         _Pragma("GCC diagnostic ignored \"-Wformat-nonliteral\"")
66
67 #define DISABLE_WARNING_MISSING_PROTOTYPES                              \
68         _Pragma("GCC diagnostic push");                                 \
69         _Pragma("GCC diagnostic ignored \"-Wmissing-prototypes\"")
70
71 #define DISABLE_WARNING_NONNULL                                         \
72         _Pragma("GCC diagnostic push");                                 \
73         _Pragma("GCC diagnostic ignored \"-Wnonnull\"")
74
75 #define DISABLE_WARNING_SHADOW                                          \
76         _Pragma("GCC diagnostic push");                                 \
77         _Pragma("GCC diagnostic ignored \"-Wshadow\"")
78
79 #define DISABLE_WARNING_INCOMPATIBLE_POINTER_TYPES                      \
80         _Pragma("GCC diagnostic push");                                 \
81         _Pragma("GCC diagnostic ignored \"-Wincompatible-pointer-types\"")
82
83 #define REENABLE_WARNING                                                \
84         _Pragma("GCC diagnostic pop")
85
86 /* automake test harness */
87 #define EXIT_TEST_SKIP 77
88
89 #define XSTRINGIFY(x) #x
90 #define STRINGIFY(x) XSTRINGIFY(x)
91
92 #define XCONCATENATE(x, y) x ## y
93 #define CONCATENATE(x, y) XCONCATENATE(x, y)
94
95 #define UNIQ_T(x, uniq) CONCATENATE(__unique_prefix_, CONCATENATE(x, uniq))
96 #define UNIQ __COUNTER__
97
98 /* builtins */
99 #if __SIZEOF_INT__ == 4
100 #define BUILTIN_FFS_U32(x) __builtin_ffs(x);
101 #elif __SIZEOF_LONG__ == 4
102 #define BUILTIN_FFS_U32(x) __builtin_ffsl(x);
103 #else
104 #error "neither int nor long are four bytes long?!?"
105 #endif
106
107 /* Rounds up */
108
109 #define ALIGN4(l) (((l) + 3) & ~3)
110 #define ALIGN8(l) (((l) + 7) & ~7)
111
112 #if __SIZEOF_POINTER__ == 8
113 #define ALIGN(l) ALIGN8(l)
114 #elif __SIZEOF_POINTER__ == 4
115 #define ALIGN(l) ALIGN4(l)
116 #else
117 #error "Wut? Pointers are neither 4 nor 8 bytes long?"
118 #endif
119
120 #define ALIGN_PTR(p) ((void*) ALIGN((unsigned long) (p)))
121 #define ALIGN4_PTR(p) ((void*) ALIGN4((unsigned long) (p)))
122 #define ALIGN8_PTR(p) ((void*) ALIGN8((unsigned long) (p)))
123
124 static inline size_t ALIGN_TO(size_t l, size_t ali) {
125         return ((l + ali - 1) & ~(ali - 1));
126 }
127
128 #define ALIGN_TO_PTR(p, ali) ((void*) ALIGN_TO((unsigned long) (p), (ali)))
129
130 /* align to next higher power-of-2 (except for: 0 => 0, overflow => 0) */
131 static inline unsigned long ALIGN_POWER2(unsigned long u) {
132         /* clz(0) is undefined */
133         if (u == 1)
134                 return 1;
135
136         /* left-shift overflow is undefined */
137         if (__builtin_clzl(u - 1UL) < 1)
138                 return 0;
139
140         return 1UL << (sizeof(u) * 8 - __builtin_clzl(u - 1UL));
141 }
142
143 #ifndef __COVERITY__
144 #  define VOID_0 ((void)0)
145 #else
146 #  define VOID_0 ((void*)0)
147 #endif
148
149 #define ELEMENTSOF(x)                                                    \
150         __extension__ (__builtin_choose_expr(                            \
151                 !__builtin_types_compatible_p(typeof(x), typeof(&*(x))), \
152                 sizeof(x)/sizeof((x)[0]),                                \
153                 VOID_0))
154
155 /*
156  * STRLEN - return the length of a string literal, minus the trailing NUL byte.
157  *          Contrary to strlen(), this is a constant expression.
158  * @x: a string literal.
159  */
160 #define STRLEN(x) (sizeof(""x"") - 1)
161
162 /*
163  * container_of - cast a member of a structure out to the containing structure
164  * @ptr: the pointer to the member.
165  * @type: the type of the container struct this is embedded in.
166  * @member: the name of the member within the struct.
167  */
168 #define container_of(ptr, type, member) __container_of(UNIQ, (ptr), type, member)
169 #define __container_of(uniq, ptr, type, member)                         \
170         __extension__ ({                                                \
171                 const typeof( ((type*)0)->member ) *UNIQ_T(A, uniq) = (ptr); \
172                 (type*)( (char *)UNIQ_T(A, uniq) - offsetof(type,member) ); \
173         })
174
175 #undef MAX
176 #define MAX(a, b) __MAX(UNIQ, (a), UNIQ, (b))
177 #define __MAX(aq, a, bq, b)                             \
178         __extension__ ({                                \
179                 const typeof(a) UNIQ_T(A, aq) = (a);    \
180                 const typeof(b) UNIQ_T(B, bq) = (b);    \
181                 UNIQ_T(A,aq) > UNIQ_T(B,bq) ? UNIQ_T(A,aq) : UNIQ_T(B,bq); \
182         })
183
184 /* evaluates to (void) if _A or _B are not constant or of different types */
185 #define CONST_MAX(_A, _B) \
186         __extension__ (__builtin_choose_expr(                           \
187                 __builtin_constant_p(_A) &&                             \
188                 __builtin_constant_p(_B) &&                             \
189                 __builtin_types_compatible_p(typeof(_A), typeof(_B)),   \
190                 ((_A) > (_B)) ? (_A) : (_B),                            \
191                 VOID_0))
192
193 /* takes two types and returns the size of the larger one */
194 #define MAXSIZE(A, B) (sizeof(union _packed_ { typeof(A) a; typeof(B) b; }))
195
196 #define MAX3(x,y,z)                                     \
197         __extension__ ({                                \
198                         const typeof(x) _c = MAX(x,y);  \
199                         MAX(_c, z);                     \
200                 })
201
202 #undef MIN
203 #define MIN(a, b) __MIN(UNIQ, (a), UNIQ, (b))
204 #define __MIN(aq, a, bq, b)                             \
205         __extension__ ({                                \
206                 const typeof(a) UNIQ_T(A, aq) = (a);    \
207                 const typeof(b) UNIQ_T(B, bq) = (b);    \
208                 UNIQ_T(A,aq) < UNIQ_T(B,bq) ? UNIQ_T(A,aq) : UNIQ_T(B,bq); \
209         })
210
211 #define MIN3(x,y,z)                                     \
212         __extension__ ({                                \
213                         const typeof(x) _c = MIN(x,y);  \
214                         MIN(_c, z);                     \
215                 })
216
217 #define LESS_BY(a, b) __LESS_BY(UNIQ, (a), UNIQ, (b))
218 #define __LESS_BY(aq, a, bq, b)                         \
219         __extension__ ({                                \
220                 const typeof(a) UNIQ_T(A, aq) = (a);    \
221                 const typeof(b) UNIQ_T(B, bq) = (b);    \
222                 UNIQ_T(A,aq) > UNIQ_T(B,bq) ? UNIQ_T(A,aq) - UNIQ_T(B,bq) : 0; \
223         })
224
225 #undef CLAMP
226 #define CLAMP(x, low, high) __CLAMP(UNIQ, (x), UNIQ, (low), UNIQ, (high))
227 #define __CLAMP(xq, x, lowq, low, highq, high)                          \
228         __extension__ ({                                                \
229                 const typeof(x) UNIQ_T(X,xq) = (x);                     \
230                 const typeof(low) UNIQ_T(LOW,lowq) = (low);             \
231                 const typeof(high) UNIQ_T(HIGH,highq) = (high);         \
232                         UNIQ_T(X,xq) > UNIQ_T(HIGH,highq) ?             \
233                                 UNIQ_T(HIGH,highq) :                    \
234                                 UNIQ_T(X,xq) < UNIQ_T(LOW,lowq) ?       \
235                                         UNIQ_T(LOW,lowq) :              \
236                                         UNIQ_T(X,xq);                   \
237         })
238
239 /* [(x + y - 1) / y] suffers from an integer overflow, even though the
240  * computation should be possible in the given type. Therefore, we use
241  * [x / y + !!(x % y)]. Note that on "Real CPUs" a division returns both the
242  * quotient and the remainder, so both should be equally fast. */
243 #define DIV_ROUND_UP(_x, _y)                                            \
244         __extension__ ({                                                \
245                 const typeof(_x) __x = (_x);                            \
246                 const typeof(_y) __y = (_y);                            \
247                 (__x / __y + !!(__x % __y));                            \
248         })
249
250 #define assert_message_se(expr, message)                                \
251         do {                                                            \
252                 if (_unlikely_(!(expr)))                                \
253                         log_assert_failed(message, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
254         } while (false)
255
256 #define assert_se(expr) assert_message_se(expr, #expr)
257
258 /* We override the glibc assert() here. */
259 #undef assert
260 #ifdef NDEBUG
261 #define assert(expr) do {} while (false)
262 #else
263 #define assert(expr) assert_message_se(expr, #expr)
264 #endif
265
266 #define assert_not_reached(t)                                           \
267         do {                                                            \
268                 log_assert_failed_unreachable(t, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
269         } while (false)
270
271 #if defined(static_assert)
272 /* static_assert() is sometimes defined in a way that trips up
273  * -Wdeclaration-after-statement, hence let's temporarily turn off
274  * this warning around it. */
275 #define assert_cc(expr)                                                 \
276         DISABLE_WARNING_DECLARATION_AFTER_STATEMENT;                    \
277         static_assert(expr, #expr);                                     \
278         REENABLE_WARNING
279 #else
280 #define assert_cc(expr)                                                 \
281         DISABLE_WARNING_DECLARATION_AFTER_STATEMENT;                    \
282         struct CONCATENATE(_assert_struct_, __COUNTER__) {              \
283                 char x[(expr) ? 0 : -1];                                \
284         };                                                              \
285         REENABLE_WARNING
286 #endif
287
288 #define assert_log(expr, message) ((_likely_(expr))                     \
289         ? (true)                                                        \
290         : (log_assert_failed_return(message, __FILE__, __LINE__, __PRETTY_FUNCTION__), false))
291
292 #define assert_return(expr, r)                                          \
293         do {                                                            \
294                 if (!assert_log(expr, #expr))                           \
295                         return (r);                                     \
296         } while (false)
297
298 #define assert_return_errno(expr, r, err)                               \
299         do {                                                            \
300                 if (!assert_log(expr, #expr)) {                         \
301                         errno = err;                                    \
302                         return (r);                                     \
303                 }                                                       \
304         } while (false)
305
306 #define PTR_TO_INT(p) ((int) ((intptr_t) (p)))
307 #define INT_TO_PTR(u) ((void *) ((intptr_t) (u)))
308 #define PTR_TO_UINT(p) ((unsigned int) ((uintptr_t) (p)))
309 #define UINT_TO_PTR(u) ((void *) ((uintptr_t) (u)))
310
311 #define PTR_TO_LONG(p) ((long) ((intptr_t) (p)))
312 #define LONG_TO_PTR(u) ((void *) ((intptr_t) (u)))
313 #define PTR_TO_ULONG(p) ((unsigned long) ((uintptr_t) (p)))
314 #define ULONG_TO_PTR(u) ((void *) ((uintptr_t) (u)))
315
316 #define PTR_TO_INT32(p) ((int32_t) ((intptr_t) (p)))
317 #define INT32_TO_PTR(u) ((void *) ((intptr_t) (u)))
318 #define PTR_TO_UINT32(p) ((uint32_t) ((uintptr_t) (p)))
319 #define UINT32_TO_PTR(u) ((void *) ((uintptr_t) (u)))
320
321 #define PTR_TO_INT64(p) ((int64_t) ((intptr_t) (p)))
322 #define INT64_TO_PTR(u) ((void *) ((intptr_t) (u)))
323 #define PTR_TO_UINT64(p) ((uint64_t) ((uintptr_t) (p)))
324 #define UINT64_TO_PTR(u) ((void *) ((uintptr_t) (u)))
325
326 #define PTR_TO_SIZE(p) ((size_t) ((uintptr_t) (p)))
327 #define SIZE_TO_PTR(u) ((void *) ((uintptr_t) (u)))
328
329 #define CHAR_TO_STR(x) ((char[2]) { x, 0 })
330
331 #define char_array_0(x) x[sizeof(x)-1] = 0;
332
333 /* Returns the number of chars needed to format variables of the
334  * specified type as a decimal string. Adds in extra space for a
335  * negative '-' prefix (hence works correctly on signed
336  * types). Includes space for the trailing NUL. */
337 #define DECIMAL_STR_MAX(type)                                           \
338         (2+(sizeof(type) <= 1 ? 3 :                                     \
339             sizeof(type) <= 2 ? 5 :                                     \
340             sizeof(type) <= 4 ? 10 :                                    \
341             sizeof(type) <= 8 ? 20 : sizeof(int[-2*(sizeof(type) > 8)])))
342
343 #define DECIMAL_STR_WIDTH(x)                            \
344         ({                                              \
345                 typeof(x) _x_ = (x);                    \
346                 unsigned ans = 1;                       \
347                 while ((_x_ /= 10) != 0)                \
348                         ans++;                          \
349                 ans;                                    \
350         })
351
352 #define SET_FLAG(v, flag, b) \
353         (v) = (b) ? ((v) | (flag)) : ((v) & ~(flag))
354 #define FLAGS_SET(v, flags) \
355         (((v) & (flags)) == (flags))
356
357 #define CASE_F(X) case X:
358 #define CASE_F_1(CASE, X) CASE_F(X)
359 #define CASE_F_2(CASE, X, ...)  CASE(X) CASE_F_1(CASE, __VA_ARGS__)
360 #define CASE_F_3(CASE, X, ...)  CASE(X) CASE_F_2(CASE, __VA_ARGS__)
361 #define CASE_F_4(CASE, X, ...)  CASE(X) CASE_F_3(CASE, __VA_ARGS__)
362 #define CASE_F_5(CASE, X, ...)  CASE(X) CASE_F_4(CASE, __VA_ARGS__)
363 #define CASE_F_6(CASE, X, ...)  CASE(X) CASE_F_5(CASE, __VA_ARGS__)
364 #define CASE_F_7(CASE, X, ...)  CASE(X) CASE_F_6(CASE, __VA_ARGS__)
365 #define CASE_F_8(CASE, X, ...)  CASE(X) CASE_F_7(CASE, __VA_ARGS__)
366 #define CASE_F_9(CASE, X, ...)  CASE(X) CASE_F_8(CASE, __VA_ARGS__)
367 #define CASE_F_10(CASE, X, ...) CASE(X) CASE_F_9(CASE, __VA_ARGS__)
368 #define CASE_F_11(CASE, X, ...) CASE(X) CASE_F_10(CASE, __VA_ARGS__)
369 #define CASE_F_12(CASE, X, ...) CASE(X) CASE_F_11(CASE, __VA_ARGS__)
370 #define CASE_F_13(CASE, X, ...) CASE(X) CASE_F_12(CASE, __VA_ARGS__)
371 #define CASE_F_14(CASE, X, ...) CASE(X) CASE_F_13(CASE, __VA_ARGS__)
372 #define CASE_F_15(CASE, X, ...) CASE(X) CASE_F_14(CASE, __VA_ARGS__)
373 #define CASE_F_16(CASE, X, ...) CASE(X) CASE_F_15(CASE, __VA_ARGS__)
374 #define CASE_F_17(CASE, X, ...) CASE(X) CASE_F_16(CASE, __VA_ARGS__)
375 #define CASE_F_18(CASE, X, ...) CASE(X) CASE_F_17(CASE, __VA_ARGS__)
376 #define CASE_F_19(CASE, X, ...) CASE(X) CASE_F_18(CASE, __VA_ARGS__)
377 #define CASE_F_20(CASE, X, ...) CASE(X) CASE_F_19(CASE, __VA_ARGS__)
378
379 #define GET_CASE_F(_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12,_13,_14,_15,_16,_17,_18,_19,_20,NAME,...) NAME
380 #define FOR_EACH_MAKE_CASE(...) \
381         GET_CASE_F(__VA_ARGS__,CASE_F_20,CASE_F_19,CASE_F_18,CASE_F_17,CASE_F_16,CASE_F_15,CASE_F_14,CASE_F_13,CASE_F_12,CASE_F_11, \
382                                CASE_F_10,CASE_F_9,CASE_F_8,CASE_F_7,CASE_F_6,CASE_F_5,CASE_F_4,CASE_F_3,CASE_F_2,CASE_F_1) \
383                    (CASE_F,__VA_ARGS__)
384
385 #define IN_SET(x, ...)                          \
386         ({                                      \
387                 bool _found = false;            \
388                 /* If the build breaks in the line below, you need to extend the case macros */ \
389                 static _unused_ char _static_assert__macros_need_to_be_extended[20 - sizeof((int[]){__VA_ARGS__})/sizeof(int)]; \
390                 switch(x) {                     \
391                 FOR_EACH_MAKE_CASE(__VA_ARGS__) \
392                         _found = true;          \
393                         break;                  \
394                 default:                        \
395                         break;                  \
396                 }                               \
397                 _found;                         \
398         })
399
400 #define SWAP_TWO(x, y) do {                        \
401                 typeof(x) _t = (x);                \
402                 (x) = (y);                         \
403                 (y) = (_t);                        \
404         } while (false)
405
406 /* Define C11 thread_local attribute even on older gcc compiler
407  * version */
408 #ifndef thread_local
409 /*
410  * Don't break on glibc < 2.16 that doesn't define __STDC_NO_THREADS__
411  * see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53769
412  */
413 #if __STDC_VERSION__ >= 201112L && !(defined(__STDC_NO_THREADS__) || (defined(__GNU_LIBRARY__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 16))
414 #define thread_local _Thread_local
415 #else
416 #define thread_local __thread
417 #endif
418 #endif
419
420 #define DEFINE_TRIVIAL_CLEANUP_FUNC(type, func)                 \
421         static inline void func##p(type *p) {                   \
422                 if (*p)                                         \
423                         func(*p);                               \
424         }
425
426 #include "log.h"