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1 /* SPDX-License-Identifier: LGPL-2.1+ */
2 #pragma once
3
4 #include <assert.h>
5 #include <inttypes.h>
6 #include <stdbool.h>
7 #include <sys/param.h>
8 #include <sys/sysmacros.h>
9 #include <sys/types.h>
10
11 #define _printf_(a, b) __attribute__ ((format (printf, a, b)))
12 #ifdef __clang__
13 # define _alloc_(...)
14 #else
15 # define _alloc_(...) __attribute__ ((alloc_size(__VA_ARGS__)))
16 #endif
17 #define _sentinel_ __attribute__ ((sentinel))
18 #define _unused_ __attribute__ ((unused))
19 #define _destructor_ __attribute__ ((destructor))
20 #define _pure_ __attribute__ ((pure))
21 #define _const_ __attribute__ ((const))
22 #define _deprecated_ __attribute__ ((deprecated))
23 #define _packed_ __attribute__ ((packed))
24 #define _malloc_ __attribute__ ((malloc))
25 #define _weak_ __attribute__ ((weak))
26 #define _likely_(x) (__builtin_expect(!!(x), 1))
27 #define _unlikely_(x) (__builtin_expect(!!(x), 0))
28 #define _public_ __attribute__ ((visibility("default")))
29 #define _hidden_ __attribute__ ((visibility("hidden")))
30 #define _weakref_(x) __attribute__((weakref(#x)))
31 #define _alignas_(x) __attribute__((aligned(__alignof(x))))
32 #define _cleanup_(x) __attribute__((cleanup(x)))
33 #if __GNUC__ >= 7
34 #define _fallthrough_ __attribute__((fallthrough))
35 #else
36 #define _fallthrough_
37 #endif
38 /* Define C11 noreturn without <stdnoreturn.h> and even on older gcc
39 * compiler versions */
40 #ifndef _noreturn_
41 #if __STDC_VERSION__ >= 201112L
42 #define _noreturn_ _Noreturn
43 #else
44 #define _noreturn_ __attribute__((noreturn))
45 #endif
46 #endif
47
48 #if !defined(HAS_FEATURE_MEMORY_SANITIZER)
49 # if defined(__has_feature)
50 # if __has_feature(memory_sanitizer)
51 # define HAS_FEATURE_MEMORY_SANITIZER 1
52 # endif
53 # endif
54 # if !defined(HAS_FEATURE_MEMORY_SANITIZER)
55 # define HAS_FEATURE_MEMORY_SANITIZER 0
56 # endif
57 #endif
58
59 /* Temporarily disable some warnings */
60 #define DISABLE_WARNING_FORMAT_NONLITERAL \
61 _Pragma("GCC diagnostic push"); \
62 _Pragma("GCC diagnostic ignored \"-Wformat-nonliteral\"")
63
64 #define DISABLE_WARNING_MISSING_PROTOTYPES \
65 _Pragma("GCC diagnostic push"); \
66 _Pragma("GCC diagnostic ignored \"-Wmissing-prototypes\"")
67
68 #define DISABLE_WARNING_NONNULL \
69 _Pragma("GCC diagnostic push"); \
70 _Pragma("GCC diagnostic ignored \"-Wnonnull\"")
71
72 #define DISABLE_WARNING_SHADOW \
73 _Pragma("GCC diagnostic push"); \
74 _Pragma("GCC diagnostic ignored \"-Wshadow\"")
75
76 #define DISABLE_WARNING_INCOMPATIBLE_POINTER_TYPES \
77 _Pragma("GCC diagnostic push"); \
78 _Pragma("GCC diagnostic ignored \"-Wincompatible-pointer-types\"")
79
80 #define REENABLE_WARNING \
81 _Pragma("GCC diagnostic pop")
82
83 /* automake test harness */
84 #define EXIT_TEST_SKIP 77
85
86 #define XSTRINGIFY(x) #x
87 #define STRINGIFY(x) XSTRINGIFY(x)
88
89 #define XCONCATENATE(x, y) x ## y
90 #define CONCATENATE(x, y) XCONCATENATE(x, y)
91
92 #define UNIQ_T(x, uniq) CONCATENATE(__unique_prefix_, CONCATENATE(x, uniq))
93 #define UNIQ __COUNTER__
94
95 /* builtins */
96 #if __SIZEOF_INT__ == 4
97 #define BUILTIN_FFS_U32(x) __builtin_ffs(x);
98 #elif __SIZEOF_LONG__ == 4
99 #define BUILTIN_FFS_U32(x) __builtin_ffsl(x);
100 #else
101 #error "neither int nor long are four bytes long?!?"
102 #endif
103
104 /* Rounds up */
105
106 #define ALIGN4(l) (((l) + 3) & ~3)
107 #define ALIGN8(l) (((l) + 7) & ~7)
108
109 #if __SIZEOF_POINTER__ == 8
110 #define ALIGN(l) ALIGN8(l)
111 #elif __SIZEOF_POINTER__ == 4
112 #define ALIGN(l) ALIGN4(l)
113 #else
114 #error "Wut? Pointers are neither 4 nor 8 bytes long?"
115 #endif
116
117 #define ALIGN_PTR(p) ((void*) ALIGN((unsigned long) (p)))
118 #define ALIGN4_PTR(p) ((void*) ALIGN4((unsigned long) (p)))
119 #define ALIGN8_PTR(p) ((void*) ALIGN8((unsigned long) (p)))
120
121 static inline size_t ALIGN_TO(size_t l, size_t ali) {
122 return ((l + ali - 1) & ~(ali - 1));
123 }
124
125 #define ALIGN_TO_PTR(p, ali) ((void*) ALIGN_TO((unsigned long) (p), (ali)))
126
127 /* align to next higher power-of-2 (except for: 0 => 0, overflow => 0) */
128 static inline unsigned long ALIGN_POWER2(unsigned long u) {
129 /* clz(0) is undefined */
130 if (u == 1)
131 return 1;
132
133 /* left-shift overflow is undefined */
134 if (__builtin_clzl(u - 1UL) < 1)
135 return 0;
136
137 return 1UL << (sizeof(u) * 8 - __builtin_clzl(u - 1UL));
138 }
139
140 #ifndef __COVERITY__
141 # define VOID_0 ((void)0)
142 #else
143 # define VOID_0 ((void*)0)
144 #endif
145
146 #define ELEMENTSOF(x) \
147 (__builtin_choose_expr( \
148 !__builtin_types_compatible_p(typeof(x), typeof(&*(x))), \
149 sizeof(x)/sizeof((x)[0]), \
150 VOID_0))
151
152 /*
153 * STRLEN - return the length of a string literal, minus the trailing NUL byte.
154 * Contrary to strlen(), this is a constant expression.
155 * @x: a string literal.
156 */
157 #define STRLEN(x) (sizeof(""x"") - 1)
158
159 /*
160 * container_of - cast a member of a structure out to the containing structure
161 * @ptr: the pointer to the member.
162 * @type: the type of the container struct this is embedded in.
163 * @member: the name of the member within the struct.
164 */
165 #define container_of(ptr, type, member) __container_of(UNIQ, (ptr), type, member)
166 #define __container_of(uniq, ptr, type, member) \
167 ({ \
168 const typeof( ((type*)0)->member ) *UNIQ_T(A, uniq) = (ptr); \
169 (type*)( (char *)UNIQ_T(A, uniq) - offsetof(type, member) ); \
170 })
171
172 #undef MAX
173 #define MAX(a, b) __MAX(UNIQ, (a), UNIQ, (b))
174 #define __MAX(aq, a, bq, b) \
175 ({ \
176 const typeof(a) UNIQ_T(A, aq) = (a); \
177 const typeof(b) UNIQ_T(B, bq) = (b); \
178 UNIQ_T(A, aq) > UNIQ_T(B, bq) ? UNIQ_T(A, aq) : UNIQ_T(B, bq); \
179 })
180
181 /* evaluates to (void) if _A or _B are not constant or of different types */
182 #define CONST_MAX(_A, _B) \
183 (__builtin_choose_expr( \
184 __builtin_constant_p(_A) && \
185 __builtin_constant_p(_B) && \
186 __builtin_types_compatible_p(typeof(_A), typeof(_B)), \
187 ((_A) > (_B)) ? (_A) : (_B), \
188 VOID_0))
189
190 /* takes two types and returns the size of the larger one */
191 #define MAXSIZE(A, B) (sizeof(union _packed_ { typeof(A) a; typeof(B) b; }))
192
193 #define MAX3(x, y, z) \
194 ({ \
195 const typeof(x) _c = MAX(x, y); \
196 MAX(_c, z); \
197 })
198
199 #undef MIN
200 #define MIN(a, b) __MIN(UNIQ, (a), UNIQ, (b))
201 #define __MIN(aq, a, bq, b) \
202 ({ \
203 const typeof(a) UNIQ_T(A, aq) = (a); \
204 const typeof(b) UNIQ_T(B, bq) = (b); \
205 UNIQ_T(A, aq) < UNIQ_T(B, bq) ? UNIQ_T(A, aq) : UNIQ_T(B, bq); \
206 })
207
208 #define MIN3(x, y, z) \
209 ({ \
210 const typeof(x) _c = MIN(x, y); \
211 MIN(_c, z); \
212 })
213
214 #define LESS_BY(a, b) __LESS_BY(UNIQ, (a), UNIQ, (b))
215 #define __LESS_BY(aq, a, bq, b) \
216 ({ \
217 const typeof(a) UNIQ_T(A, aq) = (a); \
218 const typeof(b) UNIQ_T(B, bq) = (b); \
219 UNIQ_T(A, aq) > UNIQ_T(B, bq) ? UNIQ_T(A, aq) - UNIQ_T(B, bq) : 0; \
220 })
221
222 #define CMP(a, b) __CMP(UNIQ, (a), UNIQ, (b))
223 #define __CMP(aq, a, bq, b) \
224 ({ \
225 const typeof(a) UNIQ_T(A, aq) = (a); \
226 const typeof(b) UNIQ_T(B, bq) = (b); \
227 UNIQ_T(A, aq) < UNIQ_T(B, bq) ? -1 : \
228 UNIQ_T(A, aq) > UNIQ_T(B, bq) ? 1 : 0; \
229 })
230
231 #undef CLAMP
232 #define CLAMP(x, low, high) __CLAMP(UNIQ, (x), UNIQ, (low), UNIQ, (high))
233 #define __CLAMP(xq, x, lowq, low, highq, high) \
234 ({ \
235 const typeof(x) UNIQ_T(X, xq) = (x); \
236 const typeof(low) UNIQ_T(LOW, lowq) = (low); \
237 const typeof(high) UNIQ_T(HIGH, highq) = (high); \
238 UNIQ_T(X, xq) > UNIQ_T(HIGH, highq) ? \
239 UNIQ_T(HIGH, highq) : \
240 UNIQ_T(X, xq) < UNIQ_T(LOW, lowq) ? \
241 UNIQ_T(LOW, lowq) : \
242 UNIQ_T(X, xq); \
243 })
244
245 /* [(x + y - 1) / y] suffers from an integer overflow, even though the
246 * computation should be possible in the given type. Therefore, we use
247 * [x / y + !!(x % y)]. Note that on "Real CPUs" a division returns both the
248 * quotient and the remainder, so both should be equally fast. */
249 #define DIV_ROUND_UP(_x, _y) \
250 ({ \
251 const typeof(_x) __x = (_x); \
252 const typeof(_y) __y = (_y); \
253 (__x / __y + !!(__x % __y)); \
254 })
255
256 #ifdef __COVERITY__
257
258 /* Use special definitions of assertion macros in order to prevent
259 * false positives of ASSERT_SIDE_EFFECT on Coverity static analyzer
260 * for uses of assert_se() and assert_return().
261 *
262 * These definitions make expression go through a (trivial) function
263 * call to ensure they are not discarded. Also use ! or !! to ensure
264 * the boolean expressions are seen as such.
265 *
266 * This technique has been described and recommended in:
267 * https://community.synopsys.com/s/question/0D534000046Yuzb/suppressing-assertsideeffect-for-functions-that-allow-for-sideeffects
268 */
269
270 extern void __coverity_panic__(void);
271
272 static inline int __coverity_check__(int condition) {
273 return condition;
274 }
275
276 #define assert_message_se(expr, message) \
277 do { \
278 if (__coverity_check__(!(expr))) \
279 __coverity_panic__(); \
280 } while (false)
281
282 #define assert_log(expr, message) __coverity_check__(!!(expr))
283
284 #else /* ! __COVERITY__ */
285
286 #define assert_message_se(expr, message) \
287 do { \
288 if (_unlikely_(!(expr))) \
289 log_assert_failed(message, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
290 } while (false)
291
292 #define assert_log(expr, message) ((_likely_(expr)) \
293 ? (true) \
294 : (log_assert_failed_return(message, __FILE__, __LINE__, __PRETTY_FUNCTION__), false))
295
296 #endif /* __COVERITY__ */
297
298 #define assert_se(expr) assert_message_se(expr, #expr)
299
300 /* We override the glibc assert() here. */
301 #undef assert
302 #ifdef NDEBUG
303 #define assert(expr) do {} while (false)
304 #else
305 #define assert(expr) assert_message_se(expr, #expr)
306 #endif
307
308 #define assert_not_reached(t) \
309 do { \
310 log_assert_failed_unreachable(t, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
311 } while (false)
312
313 #if defined(static_assert)
314 #define assert_cc(expr) \
315 static_assert(expr, #expr);
316 #else
317 #define assert_cc(expr) \
318 struct CONCATENATE(_assert_struct_, __COUNTER__) { \
319 char x[(expr) ? 0 : -1]; \
320 };
321 #endif
322
323 #define assert_return(expr, r) \
324 do { \
325 if (!assert_log(expr, #expr)) \
326 return (r); \
327 } while (false)
328
329 #define assert_return_errno(expr, r, err) \
330 do { \
331 if (!assert_log(expr, #expr)) { \
332 errno = err; \
333 return (r); \
334 } \
335 } while (false)
336
337 #define PTR_TO_INT(p) ((int) ((intptr_t) (p)))
338 #define INT_TO_PTR(u) ((void *) ((intptr_t) (u)))
339 #define PTR_TO_UINT(p) ((unsigned) ((uintptr_t) (p)))
340 #define UINT_TO_PTR(u) ((void *) ((uintptr_t) (u)))
341
342 #define PTR_TO_LONG(p) ((long) ((intptr_t) (p)))
343 #define LONG_TO_PTR(u) ((void *) ((intptr_t) (u)))
344 #define PTR_TO_ULONG(p) ((unsigned long) ((uintptr_t) (p)))
345 #define ULONG_TO_PTR(u) ((void *) ((uintptr_t) (u)))
346
347 #define PTR_TO_INT32(p) ((int32_t) ((intptr_t) (p)))
348 #define INT32_TO_PTR(u) ((void *) ((intptr_t) (u)))
349 #define PTR_TO_UINT32(p) ((uint32_t) ((uintptr_t) (p)))
350 #define UINT32_TO_PTR(u) ((void *) ((uintptr_t) (u)))
351
352 #define PTR_TO_INT64(p) ((int64_t) ((intptr_t) (p)))
353 #define INT64_TO_PTR(u) ((void *) ((intptr_t) (u)))
354 #define PTR_TO_UINT64(p) ((uint64_t) ((uintptr_t) (p)))
355 #define UINT64_TO_PTR(u) ((void *) ((uintptr_t) (u)))
356
357 #define PTR_TO_SIZE(p) ((size_t) ((uintptr_t) (p)))
358 #define SIZE_TO_PTR(u) ((void *) ((uintptr_t) (u)))
359
360 #define CHAR_TO_STR(x) ((char[2]) { x, 0 })
361
362 #define char_array_0(x) x[sizeof(x)-1] = 0;
363
364 /* Returns the number of chars needed to format variables of the
365 * specified type as a decimal string. Adds in extra space for a
366 * negative '-' prefix (hence works correctly on signed
367 * types). Includes space for the trailing NUL. */
368 #define DECIMAL_STR_MAX(type) \
369 (2+(sizeof(type) <= 1 ? 3 : \
370 sizeof(type) <= 2 ? 5 : \
371 sizeof(type) <= 4 ? 10 : \
372 sizeof(type) <= 8 ? 20 : sizeof(int[-2*(sizeof(type) > 8)])))
373
374 #define DECIMAL_STR_WIDTH(x) \
375 ({ \
376 typeof(x) _x_ = (x); \
377 unsigned ans = 1; \
378 while ((_x_ /= 10) != 0) \
379 ans++; \
380 ans; \
381 })
382
383 #define SET_FLAG(v, flag, b) \
384 (v) = (b) ? ((v) | (flag)) : ((v) & ~(flag))
385 #define FLAGS_SET(v, flags) \
386 (((v) & (flags)) == (flags))
387
388 #define CASE_F(X) case X:
389 #define CASE_F_1(CASE, X) CASE_F(X)
390 #define CASE_F_2(CASE, X, ...) CASE(X) CASE_F_1(CASE, __VA_ARGS__)
391 #define CASE_F_3(CASE, X, ...) CASE(X) CASE_F_2(CASE, __VA_ARGS__)
392 #define CASE_F_4(CASE, X, ...) CASE(X) CASE_F_3(CASE, __VA_ARGS__)
393 #define CASE_F_5(CASE, X, ...) CASE(X) CASE_F_4(CASE, __VA_ARGS__)
394 #define CASE_F_6(CASE, X, ...) CASE(X) CASE_F_5(CASE, __VA_ARGS__)
395 #define CASE_F_7(CASE, X, ...) CASE(X) CASE_F_6(CASE, __VA_ARGS__)
396 #define CASE_F_8(CASE, X, ...) CASE(X) CASE_F_7(CASE, __VA_ARGS__)
397 #define CASE_F_9(CASE, X, ...) CASE(X) CASE_F_8(CASE, __VA_ARGS__)
398 #define CASE_F_10(CASE, X, ...) CASE(X) CASE_F_9(CASE, __VA_ARGS__)
399 #define CASE_F_11(CASE, X, ...) CASE(X) CASE_F_10(CASE, __VA_ARGS__)
400 #define CASE_F_12(CASE, X, ...) CASE(X) CASE_F_11(CASE, __VA_ARGS__)
401 #define CASE_F_13(CASE, X, ...) CASE(X) CASE_F_12(CASE, __VA_ARGS__)
402 #define CASE_F_14(CASE, X, ...) CASE(X) CASE_F_13(CASE, __VA_ARGS__)
403 #define CASE_F_15(CASE, X, ...) CASE(X) CASE_F_14(CASE, __VA_ARGS__)
404 #define CASE_F_16(CASE, X, ...) CASE(X) CASE_F_15(CASE, __VA_ARGS__)
405 #define CASE_F_17(CASE, X, ...) CASE(X) CASE_F_16(CASE, __VA_ARGS__)
406 #define CASE_F_18(CASE, X, ...) CASE(X) CASE_F_17(CASE, __VA_ARGS__)
407 #define CASE_F_19(CASE, X, ...) CASE(X) CASE_F_18(CASE, __VA_ARGS__)
408 #define CASE_F_20(CASE, X, ...) CASE(X) CASE_F_19(CASE, __VA_ARGS__)
409
410 #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
411 #define FOR_EACH_MAKE_CASE(...) \
412 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, \
413 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) \
414 (CASE_F,__VA_ARGS__)
415
416 #define IN_SET(x, ...) \
417 ({ \
418 bool _found = false; \
419 /* If the build breaks in the line below, you need to extend the case macros. (We use "long double" as \
420 * type for the array, in the hope that checkers such as ubsan don't complain that the initializers for \
421 * the array are not representable by the base type. Ideally we'd use typeof(x) as base type, but that \
422 * doesn't work, as we want to use this on bitfields and gcc refuses typeof() on bitfields.) */ \
423 assert_cc((sizeof((long double[]){__VA_ARGS__})/sizeof(long double)) <= 20); \
424 switch(x) { \
425 FOR_EACH_MAKE_CASE(__VA_ARGS__) \
426 _found = true; \
427 break; \
428 default: \
429 break; \
430 } \
431 _found; \
432 })
433
434 #define SWAP_TWO(x, y) do { \
435 typeof(x) _t = (x); \
436 (x) = (y); \
437 (y) = (_t); \
438 } while (false)
439
440 /* Define C11 thread_local attribute even on older gcc compiler
441 * version */
442 #ifndef thread_local
443 /*
444 * Don't break on glibc < 2.16 that doesn't define __STDC_NO_THREADS__
445 * see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53769
446 */
447 #if __STDC_VERSION__ >= 201112L && !(defined(__STDC_NO_THREADS__) || (defined(__GNU_LIBRARY__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 16))
448 #define thread_local _Thread_local
449 #else
450 #define thread_local __thread
451 #endif
452 #endif
453
454 #define DEFINE_TRIVIAL_CLEANUP_FUNC(type, func) \
455 static inline void func##p(type *p) { \
456 if (*p) \
457 func(*p); \
458 }
459
460 #define _DEFINE_TRIVIAL_REF_FUNC(type, name, scope) \
461 scope type *name##_ref(type *p) { \
462 if (!p) \
463 return NULL; \
464 \
465 assert(p->n_ref > 0); \
466 p->n_ref++; \
467 return p; \
468 }
469
470 #define _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func, scope) \
471 scope type *name##_unref(type *p) { \
472 if (!p) \
473 return NULL; \
474 \
475 assert(p->n_ref > 0); \
476 p->n_ref--; \
477 if (p->n_ref > 0) \
478 return NULL; \
479 \
480 return free_func(p); \
481 }
482
483 #define DEFINE_TRIVIAL_REF_FUNC(type, name) \
484 _DEFINE_TRIVIAL_REF_FUNC(type, name,)
485 #define DEFINE_PRIVATE_TRIVIAL_REF_FUNC(type, name) \
486 _DEFINE_TRIVIAL_REF_FUNC(type, name, static)
487 #define DEFINE_PUBLIC_TRIVIAL_REF_FUNC(type, name) \
488 _DEFINE_TRIVIAL_REF_FUNC(type, name, _public_)
489
490 #define DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func) \
491 _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func,)
492 #define DEFINE_PRIVATE_TRIVIAL_UNREF_FUNC(type, name, free_func) \
493 _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func, static)
494 #define DEFINE_PUBLIC_TRIVIAL_UNREF_FUNC(type, name, free_func) \
495 _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func, _public_)
496
497 #define DEFINE_TRIVIAL_REF_UNREF_FUNC(type, name, free_func) \
498 DEFINE_TRIVIAL_REF_FUNC(type, name); \
499 DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func);
500
501 #define DEFINE_PRIVATE_TRIVIAL_REF_UNREF_FUNC(type, name, free_func) \
502 DEFINE_PRIVATE_TRIVIAL_REF_FUNC(type, name); \
503 DEFINE_PRIVATE_TRIVIAL_UNREF_FUNC(type, name, free_func);
504
505 #define DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(type, name, free_func) \
506 DEFINE_PUBLIC_TRIVIAL_REF_FUNC(type, name); \
507 DEFINE_PUBLIC_TRIVIAL_UNREF_FUNC(type, name, free_func);
508
509 #include "log.h"