m4/socklen.m4

   1 # socklen.m4 serial 10
   2 dnl Copyright (C) 2005-2007, 2009-2014 Free Software Foundation, Inc.
   3 dnl This file is free software; the Free Software Foundation
   4 dnl gives unlimited permission to copy and/or distribute it,
   5 dnl with or without modifications, as long as this notice is preserved.
   6
   7 dnl From Albert Chin, Windows fixes from Simon Josefsson.
   8
   9 dnl Check for socklen_t: historically on BSD it is an int, and in
  10 dnl POSIX 1g it is a type of its own, but some platforms use different
  11 dnl types for the argument to getsockopt, getpeername, etc.:
  12 dnl HP-UX 10.20, IRIX 6.5, OSF/1 4.0, Interix 3.5, BeOS.
  13 dnl So we have to test to find something that will work.
  14
  15 AC_DEFUN([gl_TYPE_SOCKLEN_T],
  16   [AC_REQUIRE([gl_CHECK_SOCKET_HEADERS])dnl
  17    AC_CHECK_TYPE([socklen_t], ,
  18      [AC_MSG_CHECKING([for socklen_t equivalent])
  19       AC_CACHE_VAL([gl_cv_socklen_t_equiv],
  20         [# Systems have either "struct sockaddr *" or
  21          # "void *" as the second argument to getpeername
  22          gl_cv_socklen_t_equiv=
  23          for arg2 in "struct sockaddr" void; do
  24            for t in int size_t "unsigned int" "long int" "unsigned long int"; do
  25              AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
  26                  [[#include <sys/types.h>
  27                    #include <sys/socket.h>
  28
  29                    int getpeername (int, $arg2 *, $t *);]],
  30                  [[$t len;
  31                   getpeername (0, 0, &len);]])],
  32                [gl_cv_socklen_t_equiv="$t"])
  33              test "$gl_cv_socklen_t_equiv" != "" && break
  34            done
  35            test "$gl_cv_socklen_t_equiv" != "" && break
  36          done
  37       ])
  38       if test "$gl_cv_socklen_t_equiv" = ""; then
  39         AC_MSG_ERROR([Cannot find a type to use in place of socklen_t])
  40       fi
  41       AC_MSG_RESULT([$gl_cv_socklen_t_equiv])
  42       AC_DEFINE_UNQUOTED([socklen_t], [$gl_cv_socklen_t_equiv],
  43         [type to use in place of socklen_t if not defined])],
  44      [gl_SOCKET_HEADERS])])
  45
  46 dnl On mingw32, socklen_t is in ws2tcpip.h ('int'), so we try to find
  47 dnl it there too.  But on Cygwin, wc2tcpip.h must not be included.  Users
  48 dnl of this module should use the same include pattern as gl_SOCKET_HEADERS.
  49 dnl When you change this macro, keep also in sync:
  50 dnl   - gl_CHECK_SOCKET_HEADERS,
  51 dnl   - the Include section of modules/socklen.
  52 AC_DEFUN([gl_SOCKET_HEADERS],
  53 [
  54 /* <sys/types.h> is not needed according to POSIX, but the
  55    <sys/socket.h> in i386-unknown-freebsd4.10 and
  56    powerpc-apple-darwin5.5 required it. */
  57 #include <sys/types.h>
  58 #if HAVE_SYS_SOCKET_H
  59 # include <sys/socket.h>
  60 #elif HAVE_WS2TCPIP_H
  61 # include <ws2tcpip.h>
  62 #endif
  63 ])
  64
  65 dnl Tests for the existence of the header for socket facilities.
  66 dnl Defines the C macros HAVE_SYS_SOCKET_H, HAVE_WS2TCPIP_H.
  67 dnl This macro must match gl_SOCKET_HEADERS.
  68 AC_DEFUN([gl_CHECK_SOCKET_HEADERS],
  69   [AC_CHECK_HEADERS_ONCE([sys/socket.h])
  70    if test $ac_cv_header_sys_socket_h = no; then
  71      dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make
  72      dnl the check for those headers unconditional; yet cygwin reports
  73      dnl that the headers are present but cannot be compiled (since on
  74      dnl cygwin, all socket information should come from sys/socket.h).
  75      AC_CHECK_HEADERS([ws2tcpip.h])
  76    fi
  77   ])