m4/ensc_syscallnr.m4

   1 dnl $Id$
   2
   3 dnl Copyright (C) 2004 Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
   4 dnl
   5 dnl This program is free software; you can redistribute it and/or modify
   6 dnl it under the terms of the GNU General Public License as published by
   7 dnl the Free Software Foundation; version 2 of the License.
   8 dnl
   9 dnl This program is distributed in the hope that it will be useful,
  10 dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 dnl GNU General Public License for more details.
  13 dnl
  14 dnl You should have received a copy of the GNU General Public License
  15 dnl along with this program; if not, write to the Free Software
  16 dnl Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17
  18 dnl Usage: ENSC_SYSCALLNR(<syscall>,<default>[,<fallback>])
  19
  20 AC_DEFUN([ENSC_SYSCALLNR],
  21 [
  22         AC_REQUIRE([AC_PROG_CPP])
  23         AC_REQUIRE([AC_PROG_EGREP])
  24
  25         AC_CACHE_CHECK([for number of syscall '$1'], [ensc_cv_value_syscall_$1],
  26         [
  27                 AC_LANG_PUSH(C)
  28                 AC_LANG_CONFTEST([
  29 #ifdef ENSC_SYSCALL_FALLBACK
  30 #  include ENSC_SYSCALL_FALLBACK
  31 #else
  32 #  include <asm/unistd.h>
  33 #endif
  34 #ifdef __NR_$1
  35 ensc_syscall_tmp_nr=__NR_$1;
  36 ensc_syscall_tmp_src=ENSC_MARK
  37 #endif
  38 ])
  39                 ensc_syscall_tmp_nr=
  40                 ensc_syscall_tmp_src=
  41                 test x"$ensc_syscall_tmp_nr" != x || \
  42                         eval $($CPP $CPPFLAGS -D ENSC_MARK='glibc'                                    conftest.c | $EGREP '^ensc_syscall_tmp_(nr=[[1-9]][[0-9]]*;|src=.*)$')
  43                 test x"$ensc_syscall_tmp_nr" != x -o x'$3' = x || \
  44                         eval $($CPP $CPPFLAGS -D ENSC_MARK='fallback' -D ENSC_SYSCALL_FALLBACK='"$3"' conftest.c | $EGREP '^ensc_syscall_tmp_(nr=[[1-9]][[0-9]]*;|src=.*)$')
  45                 test "$ensc_syscall_tmp_nr" || {
  46                         ensc_syscall_tmp_nr=$2
  47                         ensc_syscall_tmp_src=default
  48                 }
  49
  50                 if test x"$ensc_syscall_tmp_nr" = x; then
  51                         AC_MSG_ERROR(
  52 [Can not determine value of __NR_$1; please verify your glibc/kernelheaders, and/or set CPPFLAGS='-D__NR_$1=<value>' environment when calling configure.])
  53                 fi
  54                 AC_LANG_POP
  55
  56                 ensc_cv_value_syscall_$1="$ensc_syscall_tmp_nr/$ensc_syscall_tmp_src"
  57         ])
  58
  59         ensc_syscall_tmp_nr=${ensc_cv_value_syscall_$1%/*}
  60         ensc_syscall_tmp_src=${ensc_cv_value_syscall_$1#*/}
  61
  62         if test x"$ensc_syscall_tmp_src" != x'glibc'; then
  63                 AC_DEFINE_UNQUOTED(ENSC_SYSCALL__NR_$1, $ensc_syscall_tmp_nr, [The number of the $1 syscall])
  64         fi
  65 ])