src/nss-myhostname/ifconf.h

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

#pragma once

/***
  This file is part of systemd.

  Copyright 2008-2011 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 <inttypes.h>
#include <sys/types.h>
#include <assert.h>
#include <sys/socket.h>

struct address {
        unsigned char family;
        uint8_t address[16];
        unsigned char scope;
        int ifindex;
};

#define _public_ __attribute__ ((visibility("default")))
#define _hidden_ __attribute__ ((visibility("hidden")))

int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) _hidden_;

static inline size_t PROTO_ADDRESS_SIZE(int proto) {
        assert(proto == AF_INET || proto == AF_INET6);

        return proto == AF_INET6 ? 16 : 4;
}

static inline int address_compare(const void *_a, const void *_b) {
        const struct address *a = _a, *b = _b;

        /* Order lowest scope first, IPv4 before IPv6, lowest interface index first */

        if (a->scope < b->scope)
                return -1;
        if (a->scope > b->scope)
                return 1;

        if (a->family == AF_INET && b->family == AF_INET6)
                return -1;
        if (a->family == AF_INET6 && b->family == AF_INET)
                return 1;

        if (a->ifindex < b->ifindex)
                return -1;
        if (a->ifindex > b->ifindex)
                return 1;

        return 0;
}