systemd/src/shared/macro.h

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

#pragma once

/***
  This file is part of systemd.

  Copyright 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <assert.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <inttypes.h>

#define _printf_attr_(a,b) __attribute__ ((format (printf, a, b)))
#define _sentinel_ __attribute__ ((sentinel))
#define _noreturn_ __attribute__((noreturn))
#define _unused_ __attribute__ ((unused))
#define _destructor_ __attribute__ ((destructor))
#define _pure_ __attribute__ ((pure))
#define _const_ __attribute__ ((const))
#define _deprecated_ __attribute__ ((deprecated))
#define _packed_ __attribute__ ((packed))
#define _malloc_ __attribute__ ((malloc))
#define _weak_ __attribute__ ((weak))
#define _likely_(x) (__builtin_expect(!!(x),1))
#define _unlikely_(x) (__builtin_expect(!!(x),0))
#define _public_ __attribute__ ((visibility("default")))
#define _hidden_ __attribute__ ((visibility("hidden")))
#define _weakref_(x) __attribute__((weakref(#x)))
#define _introspect_(x) __attribute__((section("introspect." x)))
#define _alignas_(x) __attribute__((aligned(__alignof(x))))

#define XSTRINGIFY(x) #x
#define STRINGIFY(x) XSTRINGIFY(x)

/* Rounds up */
#define ALIGN(l) ALIGN_TO((l), sizeof(void*))
static inline size_t ALIGN_TO(size_t l, size_t ali) {
        return ((l + ali - 1) & ~(ali - 1));
}

#define ELEMENTSOF(x) (sizeof(x)/sizeof((x)[0]))

/*
 * container_of - cast a member of a structure out to the containing structure
 * @ptr: the pointer to the member.
 * @type: the type of the container struct this is embedded in.
 * @member: the name of the member within the struct.
 *
 */
#define container_of(ptr, type, member) ({ \
        const typeof( ((type *)0)->member ) *__mptr = (ptr); \
        (type *)( (char *)__mptr - offsetof(type,member) );})

#ifndef MAX
#define MAX(a,b)                                \
        __extension__ ({                        \
                        typeof(a) _a = (a);     \
                        typeof(b) _b = (b);     \
                        _a > _b ? _a : _b;      \
                })
#endif

#define MAX3(a,b,c)                             \
        MAX(MAX(a,b),c)

#ifndef MIN
#define MIN(a,b)                                \
        __extension__ ({                        \
                        typeof(a) _a = (a);     \
                        typeof(b) _b = (b);     \
                        _a < _b ? _a : _b;      \
                })
#endif

#define MIN3(a,b,c)                             \
        MIN(MIN(a,b),c)

#define CLAMP(x, low, high)                                             \
        __extension__ ({                                                \
                        typeof(x) _x = (x);                             \
                        typeof(low) _low = (low);                       \
                        typeof(high) _high = (high);                    \
                        ((_x > _high) ? _high : ((_x < _low) ? _low : _x)); \
                })

#define assert_se(expr)                                                 \
        do {                                                            \
                if (_unlikely_(!(expr)))                                \
                        log_assert_failed(#expr, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
        } while (false)                                                 \

/* We override the glibc assert() here. */
#undef assert
#ifdef NDEBUG
#define assert(expr) do {} while(false)
#else
#define assert(expr) assert_se(expr)
#endif

#define assert_not_reached(t)                                           \
        do {                                                            \
                log_assert_failed_unreachable(t, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
        } while (false)

#define assert_cc(expr)                            \
        do {                                       \
                switch (0) {                       \
                        case 0:                    \
                        case !!(expr):             \
                                ;                  \
                }                                  \
        } while (false)

#define PTR_TO_UINT(p) ((unsigned int) ((uintptr_t) (p)))
#define UINT_TO_PTR(u) ((void*) ((uintptr_t) (u)))

#define PTR_TO_UINT32(p) ((uint32_t) ((uintptr_t) (p)))
#define UINT32_TO_PTR(u) ((void*) ((uintptr_t) (u)))

#define PTR_TO_ULONG(p) ((unsigned long) ((uintptr_t) (p)))
#define ULONG_TO_PTR(u) ((void*) ((uintptr_t) (u)))

#define PTR_TO_INT(p) ((int) ((intptr_t) (p)))
#define INT_TO_PTR(u) ((void*) ((intptr_t) (u)))

#define TO_INT32(p) ((int32_t) ((intptr_t) (p)))
#define INT32_TO_PTR(u) ((void*) ((intptr_t) (u)))

#define PTR_TO_LONG(p) ((long) ((intptr_t) (p)))
#define LONG_TO_PTR(u) ((void*) ((intptr_t) (u)))

#define memzero(x,l) (memset((x), 0, (l)))
#define zero(x) (memzero(&(x), sizeof(x)))

#define char_array_0(x) x[sizeof(x)-1] = 0;

#define IOVEC_SET_STRING(i, s)                  \
        do {                                    \
                struct iovec *_i = &(i);        \
                char *_s = (char *)(s);         \
                _i->iov_base = _s;              \
                _i->iov_len = strlen(_s);       \
        } while(false)

static inline size_t IOVEC_TOTAL_SIZE(const struct iovec *i, unsigned n) {
        unsigned j;
        size_t r = 0;

        for (j = 0; j < n; j++)
                r += i[j].iov_len;

        return r;
}

static inline size_t IOVEC_INCREMENT(struct iovec *i, unsigned n, size_t k) {
        unsigned j;

        for (j = 0; j < n; j++) {
                size_t sub;

                if (_unlikely_(k <= 0))
                        break;

                sub = MIN(i[j].iov_len, k);
                i[j].iov_len -= sub;
                i[j].iov_base = (uint8_t*) i[j].iov_base + sub;
                k -= sub;
        }

        return k;
}

#include "log.h"