nmap/ncat/sockaddr_u.h

/***************************************************************************
 * sockaddr_u.h -- a union containing sockaddr types compatible with C99   *
 * strict-aliasing rules.                                                  *
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 ***************************************************************************/

/* $Id:$ */

#include "ncat_config.h"

#ifndef SOCKADDR_U_H_
#define SOCKADDR_U_H_

#ifdef WIN32
# include <ws2def.h>
#endif
#if HAVE_NETINET_IN_H
# include <netinet/in.h>
#endif
#if HAVE_SYS_SOCKET_H
# include <sys/socket.h>
#endif
#if HAVE_SYS_UN_H
# include <sys/un.h>
#endif
#if HAVE_LINUX_VM_SOCKETS_H
#include <linux/vm_sockets.h>
#endif

union sockaddr_u {
    struct sockaddr_storage storage;
#ifdef HAVE_SYS_UN_H
    struct sockaddr_un un;
#endif
#ifdef HAVE_LINUX_VM_SOCKETS_H
    struct sockaddr_vm vm;
#endif
    struct sockaddr_in in;
    struct sockaddr_in6 in6;
    struct sockaddr sockaddr;
};

static inline socklen_t get_socklen(const union sockaddr_u *s)
{
    switch(s->storage.ss_family) {
#ifdef HAVE_SYS_UN_H
      case AF_UNIX:
        return SUN_LEN(&s->un);
        break;
#endif
#ifdef HAVE_LINUX_VM_SOCKETS_H
      case AF_VSOCK:
        return sizeof(struct sockaddr_vm);
        break;
#endif
#ifdef HAVE_SOCKADDR_SA_LEN
      default:
        return s->sockaddr.sa_len;
        break;
#else
      case AF_INET:
        return sizeof(struct sockaddr_in);
        break;
#ifdef AF_INET6
      case AF_INET6:
        return sizeof(struct sockaddr_in6);
        break;
#endif
      default:
        return sizeof(union sockaddr_u);
        break;
#endif
    }
    return 0;
}
#endif