macros.h revision 95ec0fd4789bd249b106e282a32a08f4d1827f63
#ifndef MACROS_H
#define MACROS_H
/* several useful macros, mostly from glib.h */
#ifndef NULL
# define NULL ((void *)0)
#endif
#ifndef FALSE
# define FALSE (!1)
#endif
#ifndef TRUE
# define TRUE (!FALSE)
#endif
#define N_ELEMENTS(arr) \
(sizeof(arr) / sizeof((arr)[0]))
#define MEM_ALIGN(size) \
(((size) + MEM_ALIGN_SIZE-1) & ~((size_t) MEM_ALIGN_SIZE-1))
#define PTR_OFFSET(ptr, offset) \
((void *) (((unsigned char *) (ptr)) + (offset)))
#define CONST_PTR_OFFSET(ptr, offset) \
((const void *) (((const unsigned char *) (ptr)) + (offset)))
#define container_of(ptr, type, name) \
(type *)((uintptr_t)(ptr) - (uintptr_t)offsetof(type, name) + \
COMPILE_ERROR_IF_TYPES_NOT_COMPATIBLE(ptr, &((type *) 0)->name))
/* Don't use simply MIN/MAX, as they're often defined elsewhere in include
files that are included after this file generating tons of warnings. */
#define I_MIN(a, b) (((a) < (b)) ? (a) : (b))
#define I_MAX(a, b) (((a) > (b)) ? (a) : (b))
/* make it easier to cast from/to pointers. assumes that
sizeof(size_t) == sizeof(void *) and they're both the largest datatypes
that are allowed to be used. so, long long isn't safe with these. */
#define POINTER_CAST(i) \
((void *) ((char *) NULL + (i)))
#define POINTER_CAST_TO(p, type) \
((type) ((const char *) (p) - (const char *) NULL))
/* Define VA_COPY() to do the right thing for copying va_list variables.
config.h may have already defined VA_COPY as va_copy or __va_copy. */
#ifndef VA_COPY
# if defined (__GNUC__) && defined (__PPC__) && \
(defined (_CALL_SYSV) || defined (_WIN32))
# define VA_COPY(ap1, ap2) (*(ap1) = *(ap2))
# elif defined (VA_COPY_AS_ARRAY)
# define VA_COPY(ap1, ap2) memmove ((ap1), (ap2), sizeof (va_list))
# else /* va_list is a pointer */
# define VA_COPY(ap1, ap2) ((ap1) = (ap2))
# endif /* va_list is a pointer */
#endif
/* Provide convenience macros for handling structure
* fields through their offsets.
*/
#define STRUCT_MEMBER_P(struct_p, struct_offset) \
((void *) ((char *) (struct_p) + (long) (struct_offset)))
#define CONST_STRUCT_MEMBER_P(struct_p, struct_offset) \
((const void *) ((const char *) (struct_p) + (long) (struct_offset)))
/* Provide simple macro statement wrappers (adapted from Perl):
STMT_START { statements; } STMT_END;
can be used as a single statement, as in
if (x) STMT_START { ... } STMT_END; else ...
For gcc we will wrap the statements within `({' and `})' braces.
For SunOS they will be wrapped within `if (1)' and `else (void) 0',
and otherwise within `do' and `while (0)'. */
#if !(defined (STMT_START) && defined (STMT_END))
# if defined (__GNUC__) && !defined (__cplusplus) && \
!defined (__STRICT_ANSI__) && !defined (PEDANTIC)
# define STMT_START (void)(
# define STMT_END )
# else
# if (defined (sun) || defined (__sun__))
# define STMT_START if (1)
# define STMT_END else (void)0
# else
# define STMT_START do
# define STMT_END while (0)
# endif
# endif
#endif
/* Provide macros to feature the GCC function attribute. */
#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4)
# define ATTRS_DEFINED
# define ATTR_FORMAT(format_idx, arg_idx) \
__attribute__((format (printf, format_idx, arg_idx)))
# define ATTR_FORMAT_ARG(arg_idx) \
__attribute__((format_arg (arg_idx)))
# define ATTR_SCANF(format_idx, arg_idx) \
__attribute__((format (scanf, format_idx, arg_idx)))
# define ATTR_STRFTIME(format_idx) \
__attribute__((format (strftime, format_idx, 0)))
# define ATTR_UNUSED __attribute__((unused))
# define ATTR_NORETURN __attribute__((noreturn))
# define ATTR_CONST __attribute__((const))
# define ATTR_PURE __attribute__((pure))
#else
# define ATTR_FORMAT(format_idx, arg_idx)
# define ATTR_FORMAT_ARG(arg_idx)
# define ATTR_SCANF(format_idx, arg_idx)
# define ATTR_STRFTIME(format_idx)
# define ATTR_UNUSED
# define ATTR_NORETURN
# define ATTR_CONST
# define ATTR_PURE
#endif
#ifdef HAVE_ATTR_NULL
# define ATTR_NULL(...) __attribute__((null(__VA_ARGS__)))
#else
# define ATTR_NULL(...)
#endif
#ifdef HAVE_ATTR_NOWARN_UNUSED_RESULT
# define ATTR_NOWARN_UNUSED_RESULT __attribute__((nowarn_unused_result))
#else
# define ATTR_NOWARN_UNUSED_RESULT
#endif
#if __GNUC__ > 2
# define ATTR_MALLOC __attribute__((malloc))
#else
# define ATTR_MALLOC
#endif
#if __GNUC__ > 3
/* GCC 4.0 and later */
# define ATTR_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
# define ATTR_SENTINEL __attribute__((sentinel))
#else
# define ATTR_WARN_UNUSED_RESULT
# define ATTR_SENTINEL
#endif
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
/* GCC 4.3 and later */
# define ATTR_HOT __attribute__((hot))
# define ATTR_COLD __attribute__((cold))
#else
# define ATTR_HOT
# define ATTR_COLD
#endif
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 9)
/* GCC 4.9 and later */
# define ATTR_RETURNS_NONNULL __attribute__((returns_nonnull))
#else
# define ATTR_RETURNS_NONNULL
#endif
/* Macros to provide type safety for callback functions' context parameters */
#ifdef HAVE_TYPE_CHECKS
# define CALLBACK_TYPECHECK(callback, type) \
(COMPILE_ERROR_IF_TRUE(!__builtin_types_compatible_p( \
typeof(&callback), type)) ? 1 : 0)
#else
# define CALLBACK_TYPECHECK(callback, type) 0
#endif
#if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 0)) && !defined(__cplusplus)
# define COMPILE_ERROR_IF_TRUE(condition) \
(sizeof(char[1 - 2 * ((condition) ? 1 : 0)]) - 1)
#else
# define COMPILE_ERROR_IF_TRUE(condition) 0
#endif
#ifdef HAVE_TYPE_CHECKS
# define COMPILE_ERROR_IF_TYPES_NOT_COMPATIBLE(_a, _b) \
COMPILE_ERROR_IF_TRUE( \
!__builtin_types_compatible_p(typeof(_a), typeof(_b)))
#define COMPILE_ERROR_IF_TYPES2_NOT_COMPATIBLE(_a1, _a2, _b) \
COMPILE_ERROR_IF_TRUE( \
!__builtin_types_compatible_p(typeof(_a1), typeof(_b)) && \
!__builtin_types_compatible_p(typeof(_a2), typeof(_b)))
#else
# define COMPILE_ERROR_IF_TYPES_NOT_COMPATIBLE(_a, _b) 0
# define COMPILE_ERROR_IF_TYPES2_NOT_COMPATIBLE(_a1, _a2, _b) 0
#endif
#if __GNUC__ > 2
# define unlikely(expr) (__builtin_expect((expr) ? 1 : 0, 0) != 0)
# define likely(expr) (__builtin_expect((expr) ? 1 : 0, 1) != 0)
#else
# define unlikely(expr) expr
# define likely(expr) expr
#endif
#if defined(__clang__) && ((__clang_major__ > 4) || (__clang_major__ == 3 && __clang_minor__ >= 9))
# define ATTR_UNSIGNED_WRAPS __attribute__((no_sanitize("integer")))
#else
# define ATTR_UNSIGNED_WRAPS
#endif
/* Provide macros for error handling. */
#ifdef DISABLE_ASSERTS
# define i_assert(expr)
#else
#define i_assert(expr) STMT_START{ \
if (unlikely(!(expr))) \
i_panic("file %s: line %d (%s): assertion failed: (%s)", \
__FILE__, \
__LINE__, \
__func__, \
#expr); }STMT_END
#endif
/* Close the fd and set it to -1. This assert-crashes if fd == 0, and is a
no-op if fd == -1. Normally fd == 0 would happen only if an uninitialized
fd is attempted to be closed, which is a bug. */
#define i_close_fd(fd) STMT_START { \
if (*fd != -1) { \
i_assert(*fd > 0); \
if (unlikely(close_keep_errno(fd) < 0)) \
i_error("close(%d[%s:%d]) failed: %m", \
*(fd), __FILE__, __LINE__); \
} \
} STMT_END
#define i_unreached() \
i_panic("file %s: line %d: unreached", __FILE__, __LINE__)
/* Convenience macros to test the versions of dovecot. */
#if defined DOVECOT_VERSION_MAJOR && defined DOVECOT_VERSION_MINOR
# define DOVECOT_PREREQ(maj, min) \
((DOVECOT_VERSION_MAJOR << 16) + DOVECOT_VERSION_MINOR >= ((maj) << 16) + (min))
#else
# define DOVECOT_PREREQ(maj, min) 0
#endif
#ifdef __cplusplus
# undef STATIC_ARRAY
# define STATIC_ARRAY
#endif
/* Convenience wrappers for initializing a struct */
#define i_zero(p) memset(p, 0, sizeof(*(p)))
#define i_zero_safe(p) safe_memset(p, 0, sizeof(*(p)))
#define ST_CHANGED(st_a, st_b) \
((st_a).st_mtime != (st_b).st_mtime || \
ST_MTIME_NSEC(st_a) != ST_MTIME_NSEC(st_b) || \
(st_a).st_size != (st_b).st_size || \
(st_a).st_ino != (st_b).st_ino)
#endif