src/basic/macro.h

   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 _section_(x) __attribute__((__section__(x)))
  19 #define _used_ __attribute__((__used__))
  20 #define _unused_ __attribute__ ((__unused__))
  21 #define _destructor_ __attribute__ ((__destructor__))
  22 #define _pure_ __attribute__ ((__pure__))
  23 #define _const_ __attribute__ ((__const__))
  24 #define _deprecated_ __attribute__ ((__deprecated__))
  25 #define _packed_ __attribute__ ((__packed__))
  26 #define _malloc_ __attribute__ ((__malloc__))
  27 #define _weak_ __attribute__ ((__weak__))
  28 #define _likely_(x) (__builtin_expect(!!(x), 1))
  29 #define _unlikely_(x) (__builtin_expect(!!(x), 0))
  30 #define _public_ __attribute__ ((__visibility__("default")))
  31 #define _hidden_ __attribute__ ((__visibility__("hidden")))
  32 #define _weakref_(x) __attribute__((__weakref__(#x)))
  33 #define _align_(x) __attribute__((__aligned__(x)))
  34 #define _alignas_(x) __attribute__((__aligned__(__alignof(x))))
  35 #define _alignptr_ __attribute__((__aligned__(sizeof(void*))))
  36 #define _cleanup_(x) __attribute__((__cleanup__(x)))
  37 #if __GNUC__ >= 7
  38 #define _fallthrough_ __attribute__((__fallthrough__))
  39 #else
  40 #define _fallthrough_
  41 #endif
  42 /* Define C11 noreturn without <stdnoreturn.h> and even on older gcc
  43  * compiler versions */
  44 #ifndef _noreturn_
  45 #if __STDC_VERSION__ >= 201112L
  46 #define _noreturn_ _Noreturn
  47 #else
  48 #define _noreturn_ __attribute__((__noreturn__))
  49 #endif
  50 #endif
  51
  52 #if !defined(HAS_FEATURE_MEMORY_SANITIZER)
  53 #  if defined(__has_feature)
  54 #    if __has_feature(memory_sanitizer)
  55 #      define HAS_FEATURE_MEMORY_SANITIZER 1
  56 #    endif
  57 #  endif
  58 #  if !defined(HAS_FEATURE_MEMORY_SANITIZER)
  59 #    define HAS_FEATURE_MEMORY_SANITIZER 0
  60 #  endif
  61 #endif
  62
  63 /* Temporarily disable some warnings */
  64 #define DISABLE_WARNING_FORMAT_NONLITERAL                               \
  65         _Pragma("GCC diagnostic push");                                 \
  66         _Pragma("GCC diagnostic ignored \"-Wformat-nonliteral\"")
  67
  68 #define DISABLE_WARNING_MISSING_PROTOTYPES                              \
  69         _Pragma("GCC diagnostic push");                                 \
  70         _Pragma("GCC diagnostic ignored \"-Wmissing-prototypes\"")
  71
  72 #define DISABLE_WARNING_NONNULL                                         \
  73         _Pragma("GCC diagnostic push");                                 \
  74         _Pragma("GCC diagnostic ignored \"-Wnonnull\"")
  75
  76 #define DISABLE_WARNING_SHADOW                                          \
  77         _Pragma("GCC diagnostic push");                                 \
  78         _Pragma("GCC diagnostic ignored \"-Wshadow\"")
  79
  80 #define DISABLE_WARNING_INCOMPATIBLE_POINTER_TYPES                      \
  81         _Pragma("GCC diagnostic push");                                 \
  82         _Pragma("GCC diagnostic ignored \"-Wincompatible-pointer-types\"")
  83
  84 #define REENABLE_WARNING                                                \
  85         _Pragma("GCC diagnostic pop")
  86
  87 /* automake test harness */
  88 #define EXIT_TEST_SKIP 77
  89
  90 #define XSTRINGIFY(x) #x
  91 #define STRINGIFY(x) XSTRINGIFY(x)
  92
  93 #define XCONCATENATE(x, y) x ## y
  94 #define CONCATENATE(x, y) XCONCATENATE(x, y)
  95
  96 #define UNIQ_T(x, uniq) CONCATENATE(__unique_prefix_, CONCATENATE(x, uniq))
  97 #define UNIQ __COUNTER__
  98
  99 /* builtins */
 100 #if __SIZEOF_INT__ == 4
 101 #define BUILTIN_FFS_U32(x) __builtin_ffs(x);
 102 #elif __SIZEOF_LONG__ == 4
 103 #define BUILTIN_FFS_U32(x) __builtin_ffsl(x);
 104 #else
 105 #error "neither int nor long are four bytes long?!?"
 106 #endif
 107
 108 /* Rounds up */
 109
 110 #define ALIGN4(l) (((l) + 3) & ~3)
 111 #define ALIGN8(l) (((l) + 7) & ~7)
 112
 113 #if __SIZEOF_POINTER__ == 8
 114 #define ALIGN(l) ALIGN8(l)
 115 #elif __SIZEOF_POINTER__ == 4
 116 #define ALIGN(l) ALIGN4(l)
 117 #else
 118 #error "Wut? Pointers are neither 4 nor 8 bytes long?"
 119 #endif
 120
 121 #define ALIGN_PTR(p) ((void*) ALIGN((unsigned long) (p)))
 122 #define ALIGN4_PTR(p) ((void*) ALIGN4((unsigned long) (p)))
 123 #define ALIGN8_PTR(p) ((void*) ALIGN8((unsigned long) (p)))
 124
 125 static inline size_t ALIGN_TO(size_t l, size_t ali) {
 126         return ((l + ali - 1) & ~(ali - 1));
 127 }
 128
 129 #define ALIGN_TO_PTR(p, ali) ((void*) ALIGN_TO((unsigned long) (p), (ali)))
 130
 131 /* align to next higher power-of-2 (except for: 0 => 0, overflow => 0) */
 132 static inline unsigned long ALIGN_POWER2(unsigned long u) {
 133         /* clz(0) is undefined */
 134         if (u == 1)
 135                 return 1;
 136
 137         /* left-shift overflow is undefined */
 138         if (__builtin_clzl(u - 1UL) < 1)
 139                 return 0;
 140
 141         return 1UL << (sizeof(u) * 8 - __builtin_clzl(u - 1UL));
 142 }
 143
 144 #ifndef __COVERITY__
 145 #  define VOID_0 ((void)0)
 146 #else
 147 #  define VOID_0 ((void*)0)
 148 #endif
 149
 150 #define ELEMENTSOF(x)                                                   \
 151         (__builtin_choose_expr(                                         \
 152                 !__builtin_types_compatible_p(typeof(x), typeof(&*(x))), \
 153                 sizeof(x)/sizeof((x)[0]),                               \
 154                 VOID_0))
 155
 156 /*
 157  * STRLEN - return the length of a string literal, minus the trailing NUL byte.
 158  *          Contrary to strlen(), this is a constant expression.
 159  * @x: a string literal.
 160  */
 161 #define STRLEN(x) (sizeof(""x"") - 1)
 162
 163 /*
 164  * container_of - cast a member of a structure out to the containing structure
 165  * @ptr: the pointer to the member.
 166  * @type: the type of the container struct this is embedded in.
 167  * @member: the name of the member within the struct.
 168  */
 169 #define container_of(ptr, type, member) __container_of(UNIQ, (ptr), type, member)
 170 #define __container_of(uniq, ptr, type, member)                         \
 171         ({                                                              \
 172                 const typeof( ((type*)0)->member ) *UNIQ_T(A, uniq) = (ptr); \
 173                 (type*)( (char *)UNIQ_T(A, uniq) - offsetof(type, member) ); \
 174         })
 175
 176 #undef MAX
 177 #define MAX(a, b) __MAX(UNIQ, (a), UNIQ, (b))
 178 #define __MAX(aq, a, bq, b)                             \
 179         ({                                              \
 180                 const typeof(a) UNIQ_T(A, aq) = (a);    \
 181                 const typeof(b) UNIQ_T(B, bq) = (b);    \
 182                 UNIQ_T(A, aq) > UNIQ_T(B, bq) ? UNIQ_T(A, aq) : UNIQ_T(B, bq); \
 183         })
 184
 185 /* evaluates to (void) if _A or _B are not constant or of different types */
 186 #define CONST_MAX(_A, _B) \
 187         (__builtin_choose_expr(                                         \
 188                 __builtin_constant_p(_A) &&                             \
 189                 __builtin_constant_p(_B) &&                             \
 190                 __builtin_types_compatible_p(typeof(_A), typeof(_B)),   \
 191                 ((_A) > (_B)) ? (_A) : (_B),                            \
 192                 VOID_0))
 193
 194 /* takes two types and returns the size of the larger one */
 195 #define MAXSIZE(A, B) (sizeof(union _packed_ { typeof(A) a; typeof(B) b; }))
 196
 197 #define MAX3(x, y, z)                                   \
 198         ({                                              \
 199                 const typeof(x) _c = MAX(x, y);         \
 200                 MAX(_c, z);                             \
 201         })
 202
 203 #undef MIN
 204 #define MIN(a, b) __MIN(UNIQ, (a), UNIQ, (b))
 205 #define __MIN(aq, a, bq, b)                             \
 206         ({                                              \
 207                 const typeof(a) UNIQ_T(A, aq) = (a);    \
 208                 const typeof(b) UNIQ_T(B, bq) = (b);    \
 209                 UNIQ_T(A, aq) < UNIQ_T(B, bq) ? UNIQ_T(A, aq) : UNIQ_T(B, bq); \
 210         })
 211
 212 #define MIN3(x, y, z)                                   \
 213         ({                                              \
 214                 const typeof(x) _c = MIN(x, y);         \
 215                 MIN(_c, z);                             \
 216         })
 217
 218 #define LESS_BY(a, b) __LESS_BY(UNIQ, (a), UNIQ, (b))
 219 #define __LESS_BY(aq, a, bq, b)                         \
 220         ({                                              \
 221                 const typeof(a) UNIQ_T(A, aq) = (a);    \
 222                 const typeof(b) UNIQ_T(B, bq) = (b);    \
 223                 UNIQ_T(A, aq) > UNIQ_T(B, bq) ? UNIQ_T(A, aq) - UNIQ_T(B, bq) : 0; \
 224         })
 225
 226 #define CMP(a, b) __CMP(UNIQ, (a), UNIQ, (b))
 227 #define __CMP(aq, a, bq, b)                             \
 228         ({                                              \
 229                 const typeof(a) UNIQ_T(A, aq) = (a);    \
 230                 const typeof(b) UNIQ_T(B, bq) = (b);    \
 231                 UNIQ_T(A, aq) < UNIQ_T(B, bq) ? -1 :    \
 232                 UNIQ_T(A, aq) > UNIQ_T(B, bq) ? 1 : 0;  \
 233         })
 234
 235 #undef CLAMP
 236 #define CLAMP(x, low, high) __CLAMP(UNIQ, (x), UNIQ, (low), UNIQ, (high))
 237 #define __CLAMP(xq, x, lowq, low, highq, high)                          \
 238         ({                                                              \
 239                 const typeof(x) UNIQ_T(X, xq) = (x);                    \
 240                 const typeof(low) UNIQ_T(LOW, lowq) = (low);            \
 241                 const typeof(high) UNIQ_T(HIGH, highq) = (high);        \
 242                         UNIQ_T(X, xq) > UNIQ_T(HIGH, highq) ?           \
 243                                 UNIQ_T(HIGH, highq) :                   \
 244                                 UNIQ_T(X, xq) < UNIQ_T(LOW, lowq) ?     \
 245                                         UNIQ_T(LOW, lowq) :             \
 246                                         UNIQ_T(X, xq);                  \
 247         })
 248
 249 /* [(x + y - 1) / y] suffers from an integer overflow, even though the
 250  * computation should be possible in the given type. Therefore, we use
 251  * [x / y + !!(x % y)]. Note that on "Real CPUs" a division returns both the
 252  * quotient and the remainder, so both should be equally fast. */
 253 #define DIV_ROUND_UP(x, y) __DIV_ROUND_UP(UNIQ, (x), UNIQ, (y))
 254 #define __DIV_ROUND_UP(xq, x, yq, y)                                    \
 255         ({                                                              \
 256                 const typeof(x) UNIQ_T(X, xq) = (x);                    \
 257                 const typeof(y) UNIQ_T(Y, yq) = (y);                    \
 258                 (UNIQ_T(X, xq) / UNIQ_T(Y, yq) + !!(UNIQ_T(X, xq) % UNIQ_T(Y, yq))); \
 259         })
 260
 261 #ifdef __COVERITY__
 262
 263 /* Use special definitions of assertion macros in order to prevent
 264  * false positives of ASSERT_SIDE_EFFECT on Coverity static analyzer
 265  * for uses of assert_se() and assert_return().
 266  *
 267  * These definitions make expression go through a (trivial) function
 268  * call to ensure they are not discarded. Also use ! or !! to ensure
 269  * the boolean expressions are seen as such.
 270  *
 271  * This technique has been described and recommended in:
 272  * https://community.synopsys.com/s/question/0D534000046Yuzb/suppressing-assertsideeffect-for-functions-that-allow-for-sideeffects
 273  */
 274
 275 extern void __coverity_panic__(void);
 276
 277 static inline int __coverity_check__(int condition) {
 278         return condition;
 279 }
 280
 281 #define assert_message_se(expr, message)                                \
 282         do {                                                            \
 283                 if (__coverity_check__(!(expr)))                        \
 284                         __coverity_panic__();                           \
 285         } while (false)
 286
 287 #define assert_log(expr, message) __coverity_check__(!!(expr))
 288
 289 #else  /* ! __COVERITY__ */
 290
 291 #define assert_message_se(expr, message)                                \
 292         do {                                                            \
 293                 if (_unlikely_(!(expr)))                                \
 294                         log_assert_failed(message, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
 295         } while (false)
 296
 297 #define assert_log(expr, message) ((_likely_(expr))                     \
 298         ? (true)                                                        \
 299         : (log_assert_failed_return(message, __FILE__, __LINE__, __PRETTY_FUNCTION__), false))
 300
 301 #endif  /* __COVERITY__ */
 302
 303 #define assert_se(expr) assert_message_se(expr, #expr)
 304
 305 /* We override the glibc assert() here. */
 306 #undef assert
 307 #ifdef NDEBUG
 308 #define assert(expr) do {} while (false)
 309 #else
 310 #define assert(expr) assert_message_se(expr, #expr)
 311 #endif
 312
 313 #define assert_not_reached(t)                                           \
 314         do {                                                            \
 315                 log_assert_failed_unreachable(t, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
 316         } while (false)
 317
 318 #if defined(static_assert)
 319 #define assert_cc(expr)                                                 \
 320         static_assert(expr, #expr);
 321 #else
 322 #define assert_cc(expr)                                                 \
 323         struct CONCATENATE(_assert_struct_, __COUNTER__) {              \
 324                 char x[(expr) ? 0 : -1];                                \
 325         };
 326 #endif
 327
 328 #define assert_return(expr, r)                                          \
 329         do {                                                            \
 330                 if (!assert_log(expr, #expr))                           \
 331                         return (r);                                     \
 332         } while (false)
 333
 334 #define assert_return_errno(expr, r, err)                               \
 335         do {                                                            \
 336                 if (!assert_log(expr, #expr)) {                         \
 337                         errno = err;                                    \
 338                         return (r);                                     \
 339                 }                                                       \
 340         } while (false)
 341
 342 #define return_with_errno(r, err)                     \
 343         do {                                          \
 344                 errno = abs(err);                     \
 345                 return r;                             \
 346         } while (false)
 347
 348 #define PTR_TO_INT(p) ((int) ((intptr_t) (p)))
 349 #define INT_TO_PTR(u) ((void *) ((intptr_t) (u)))
 350 #define PTR_TO_UINT(p) ((unsigned) ((uintptr_t) (p)))
 351 #define UINT_TO_PTR(u) ((void *) ((uintptr_t) (u)))
 352
 353 #define PTR_TO_LONG(p) ((long) ((intptr_t) (p)))
 354 #define LONG_TO_PTR(u) ((void *) ((intptr_t) (u)))
 355 #define PTR_TO_ULONG(p) ((unsigned long) ((uintptr_t) (p)))
 356 #define ULONG_TO_PTR(u) ((void *) ((uintptr_t) (u)))
 357
 358 #define PTR_TO_INT32(p) ((int32_t) ((intptr_t) (p)))
 359 #define INT32_TO_PTR(u) ((void *) ((intptr_t) (u)))
 360 #define PTR_TO_UINT32(p) ((uint32_t) ((uintptr_t) (p)))
 361 #define UINT32_TO_PTR(u) ((void *) ((uintptr_t) (u)))
 362
 363 #define PTR_TO_INT64(p) ((int64_t) ((intptr_t) (p)))
 364 #define INT64_TO_PTR(u) ((void *) ((intptr_t) (u)))
 365 #define PTR_TO_UINT64(p) ((uint64_t) ((uintptr_t) (p)))
 366 #define UINT64_TO_PTR(u) ((void *) ((uintptr_t) (u)))
 367
 368 #define PTR_TO_SIZE(p) ((size_t) ((uintptr_t) (p)))
 369 #define SIZE_TO_PTR(u) ((void *) ((uintptr_t) (u)))
 370
 371 #define CHAR_TO_STR(x) ((char[2]) { x, 0 })
 372
 373 #define char_array_0(x) x[sizeof(x)-1] = 0;
 374
 375 /* Returns the number of chars needed to format variables of the
 376  * specified type as a decimal string. Adds in extra space for a
 377  * negative '-' prefix (hence works correctly on signed
 378  * types). Includes space for the trailing NUL. */
 379 #define DECIMAL_STR_MAX(type)                                           \
 380         (2+(sizeof(type) <= 1 ? 3 :                                     \
 381             sizeof(type) <= 2 ? 5 :                                     \
 382             sizeof(type) <= 4 ? 10 :                                    \
 383             sizeof(type) <= 8 ? 20 : sizeof(int[-2*(sizeof(type) > 8)])))
 384
 385 #define DECIMAL_STR_WIDTH(x)                            \
 386         ({                                              \
 387                 typeof(x) _x_ = (x);                    \
 388                 unsigned ans = 1;                       \
 389                 while ((_x_ /= 10) != 0)                \
 390                         ans++;                          \
 391                 ans;                                    \
 392         })
 393
 394 #define SET_FLAG(v, flag, b) \
 395         (v) = (b) ? ((v) | (flag)) : ((v) & ~(flag))
 396 #define FLAGS_SET(v, flags) \
 397         ((~(v) & (flags)) == 0)
 398
 399 #define CASE_F(X) case X:
 400 #define CASE_F_1(CASE, X) CASE_F(X)
 401 #define CASE_F_2(CASE, X, ...)  CASE(X) CASE_F_1(CASE, __VA_ARGS__)
 402 #define CASE_F_3(CASE, X, ...)  CASE(X) CASE_F_2(CASE, __VA_ARGS__)
 403 #define CASE_F_4(CASE, X, ...)  CASE(X) CASE_F_3(CASE, __VA_ARGS__)
 404 #define CASE_F_5(CASE, X, ...)  CASE(X) CASE_F_4(CASE, __VA_ARGS__)
 405 #define CASE_F_6(CASE, X, ...)  CASE(X) CASE_F_5(CASE, __VA_ARGS__)
 406 #define CASE_F_7(CASE, X, ...)  CASE(X) CASE_F_6(CASE, __VA_ARGS__)
 407 #define CASE_F_8(CASE, X, ...)  CASE(X) CASE_F_7(CASE, __VA_ARGS__)
 408 #define CASE_F_9(CASE, X, ...)  CASE(X) CASE_F_8(CASE, __VA_ARGS__)
 409 #define CASE_F_10(CASE, X, ...) CASE(X) CASE_F_9(CASE, __VA_ARGS__)
 410 #define CASE_F_11(CASE, X, ...) CASE(X) CASE_F_10(CASE, __VA_ARGS__)
 411 #define CASE_F_12(CASE, X, ...) CASE(X) CASE_F_11(CASE, __VA_ARGS__)
 412 #define CASE_F_13(CASE, X, ...) CASE(X) CASE_F_12(CASE, __VA_ARGS__)
 413 #define CASE_F_14(CASE, X, ...) CASE(X) CASE_F_13(CASE, __VA_ARGS__)
 414 #define CASE_F_15(CASE, X, ...) CASE(X) CASE_F_14(CASE, __VA_ARGS__)
 415 #define CASE_F_16(CASE, X, ...) CASE(X) CASE_F_15(CASE, __VA_ARGS__)
 416 #define CASE_F_17(CASE, X, ...) CASE(X) CASE_F_16(CASE, __VA_ARGS__)
 417 #define CASE_F_18(CASE, X, ...) CASE(X) CASE_F_17(CASE, __VA_ARGS__)
 418 #define CASE_F_19(CASE, X, ...) CASE(X) CASE_F_18(CASE, __VA_ARGS__)
 419 #define CASE_F_20(CASE, X, ...) CASE(X) CASE_F_19(CASE, __VA_ARGS__)
 420
 421 #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
 422 #define FOR_EACH_MAKE_CASE(...) \
 423         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, \
 424                                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) \
 425                    (CASE_F,__VA_ARGS__)
 426
 427 #define IN_SET(x, ...)                          \
 428         ({                                      \
 429                 bool _found = false;            \
 430                 /* If the build breaks in the line below, you need to extend the case macros. (We use "long double" as  \
 431                  * type for the array, in the hope that checkers such as ubsan don't complain that the initializers for \
 432                  * the array are not representable by the base type. Ideally we'd use typeof(x) as base type, but that  \
 433                  * doesn't work, as we want to use this on bitfields and gcc refuses typeof() on bitfields.) */         \
 434                 assert_cc((sizeof((long double[]){__VA_ARGS__})/sizeof(long double)) <= 20); \
 435                 switch(x) {                     \
 436                 FOR_EACH_MAKE_CASE(__VA_ARGS__) \
 437                         _found = true;          \
 438                         break;                  \
 439                 default:                        \
 440                         break;                  \
 441                 }                               \
 442                 _found;                         \
 443         })
 444
 445 #define SWAP_TWO(x, y) do {                        \
 446                 typeof(x) _t = (x);                \
 447                 (x) = (y);                         \
 448                 (y) = (_t);                        \
 449         } while (false)
 450
 451 /* Define C11 thread_local attribute even on older gcc compiler
 452  * version */
 453 #ifndef thread_local
 454 /*
 455  * Don't break on glibc < 2.16 that doesn't define __STDC_NO_THREADS__
 456  * see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53769
 457  */
 458 #if __STDC_VERSION__ >= 201112L && !(defined(__STDC_NO_THREADS__) || (defined(__GNU_LIBRARY__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 16))
 459 #define thread_local _Thread_local
 460 #else
 461 #define thread_local __thread
 462 #endif
 463 #endif
 464
 465 #define DEFINE_TRIVIAL_CLEANUP_FUNC(type, func)                 \
 466         static inline void func##p(type *p) {                   \
 467                 if (*p)                                         \
 468                         func(*p);                               \
 469         }
 470
 471 #define _DEFINE_TRIVIAL_REF_FUNC(type, name, scope)             \
 472         scope type *name##_ref(type *p) {                       \
 473                 if (!p)                                         \
 474                         return NULL;                            \
 475                                                                 \
 476                 assert(p->n_ref > 0);                           \
 477                 p->n_ref++;                                     \
 478                 return p;                                       \
 479         }
 480
 481 #define _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func, scope) \
 482         scope type *name##_unref(type *p) {                      \
 483                 if (!p)                                          \
 484                         return NULL;                             \
 485                                                                  \
 486                 assert(p->n_ref > 0);                            \
 487                 p->n_ref--;                                      \
 488                 if (p->n_ref > 0)                                \
 489                         return NULL;                             \
 490                                                                  \
 491                 return free_func(p);                             \
 492         }
 493
 494 #define DEFINE_TRIVIAL_REF_FUNC(type, name)     \
 495         _DEFINE_TRIVIAL_REF_FUNC(type, name,)
 496 #define DEFINE_PRIVATE_TRIVIAL_REF_FUNC(type, name)     \
 497         _DEFINE_TRIVIAL_REF_FUNC(type, name, static)
 498 #define DEFINE_PUBLIC_TRIVIAL_REF_FUNC(type, name)      \
 499         _DEFINE_TRIVIAL_REF_FUNC(type, name, _public_)
 500
 501 #define DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func)        \
 502         _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func,)
 503 #define DEFINE_PRIVATE_TRIVIAL_UNREF_FUNC(type, name, free_func)        \
 504         _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func, static)
 505 #define DEFINE_PUBLIC_TRIVIAL_UNREF_FUNC(type, name, free_func)         \
 506         _DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func, _public_)
 507
 508 #define DEFINE_TRIVIAL_REF_UNREF_FUNC(type, name, free_func)    \
 509         DEFINE_TRIVIAL_REF_FUNC(type, name);                    \
 510         DEFINE_TRIVIAL_UNREF_FUNC(type, name, free_func);
 511
 512 #define DEFINE_PRIVATE_TRIVIAL_REF_UNREF_FUNC(type, name, free_func)    \
 513         DEFINE_PRIVATE_TRIVIAL_REF_FUNC(type, name);                    \
 514         DEFINE_PRIVATE_TRIVIAL_UNREF_FUNC(type, name, free_func);
 515
 516 #define DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(type, name, free_func)    \
 517         DEFINE_PUBLIC_TRIVIAL_REF_FUNC(type, name);                    \
 518         DEFINE_PUBLIC_TRIVIAL_UNREF_FUNC(type, name, free_func);
 519
 520 #include "log.h"