xapian-core/common/safesyssocket.h

   1 /** @file safesyssocket.h
   2  * @brief #include <sys/socket.h> with portability workarounds.
   3  */
   4 /* Copyright (C) 2012,2013,2014 Olly Betts
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifndef XAPIAN_INCLUDED_SAFESYSSOCKET_H
  22 #define XAPIAN_INCLUDED_SAFESYSSOCKET_H
  23
  24 #ifndef __WIN32__
  25 // Some older BSDs require sys/types.h to be included first.
  26 # include <sys/types.h>
  27 # include <sys/socket.h>
  28 #else
  29 # include "safewinsock2.h"
  30 #endif
  31
  32 #ifndef SOCK_CLOEXEC
  33 # define SOCK_CLOEXEC 0
  34 #else
  35 // On Linux at least, sometimes SOCK_CLOEXEC is defined but the kernel doesn't
  36 // handle it in socket() or socketpair():
  37
  38 # include "safeerrno.h"
  39
  40 inline int socket_(int domain, int type, int protocol) {
  41     // Usually type is passed a constant, so we'll collapse to one branch or
  42     // the other here.  The case where SOCK_CLOEXEC == 0 is handled suitably.
  43     if (type & SOCK_CLOEXEC) {
  44         int save_errno = errno;
  45         int r = socket(domain, type, protocol);
  46         if (r != 0 && errno == EINVAL) {
  47             errno = save_errno;
  48             r = socket(domain, type &~ SOCK_CLOEXEC, protocol);
  49         }
  50         return r;
  51     } else {
  52         return socket(domain, type, protocol);
  53     }
  54 }
  55
  56 inline int socketpair_(int domain, int type, int protocol, int *sv) {
  57     // Usually type is passed a constant, so we'll collapse to one branch or
  58     // the other here.  The case where SOCK_CLOEXEC == 0 is handled suitably.
  59     if (type & SOCK_CLOEXEC) {
  60         int save_errno = errno;
  61         int r = socketpair(domain, type, protocol, sv);
  62         if (r != 0 && errno == EINVAL) {
  63             errno = save_errno;
  64             r = socketpair(domain, type &~ SOCK_CLOEXEC, protocol, sv);
  65         }
  66         return r;
  67     } else {
  68         return socketpair(domain, type, protocol, sv);
  69     }
  70 }
  71
  72 # ifdef socket
  73 #  undef socket
  74 # endif
  75 # define socket(D,T,P) socket_(D,T,P)
  76 # ifdef socketpair
  77 #  undef socketpair
  78 # endif
  79 # define socketpair(D,T,P,S) socketpair_(D,T,P,S)
  80 #endif
  81
  82 #endif // XAPIAN_INCLUDED_SAFESYSSOCKET_H