m4/ensc_syscall.m4

   1 dnl $Id: ensc_syscall.m4,v 1.6 2005/05/19 18:04:12 ensc Exp $
   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_SYSCALL
  19
  20 AC_DEFUN([ENSC_SYSCALL_ALTERNATIVE],
  21 [
  22         AC_MSG_CHECKING([whether to use alternative _syscallX macros])
  23         AC_ARG_ENABLE([alternative-syscalls],
  24                       [AC_HELP_STRING([--disable-alternative-syscalls],
  25                                       [do not use the alternative _syscallX macros
  26                                        provided by Herbert Poetzl (default: use them)])],
  27                       [case $enableval in
  28                            (yes|no)   ensc_use_alternative_syscall_macros=$enableval;;
  29                            (*)        AC_MSG_ERROR(['$enableval' is not a valid value for '--disable-alternative-syscalls']);;
  30                        esac],
  31                       [ensc_use_alternative_syscall_macros=yes])
  32
  33         case $ensc_use_alternative_syscall_macros in
  34                 (yes)   AC_DEFINE(ENSC_USE_ALTERNATIVE_SYSCALL_MACROS, 1, [Use alternative _syscallX macros]);;
  35         esac
  36
  37         AC_MSG_RESULT([$ensc_use_alternative_syscall_macros])
  38 ])
  39
  40 AC_DEFUN([ENSC_SYSCALL],
  41 [
  42         AC_REQUIRE([ENSC_KERNEL_HEADERS])
  43         AC_REQUIRE([ENSC_SYSCALL_ALTERNATIVE])
  44
  45         AC_MSG_CHECKING([for syscall(2) invocation method])
  46         AC_ARG_WITH([syscall],
  47                     [AC_HELP_STRING([--with-syscall=METHOD],
  48                                     [call syscall(2) with the specified METHOD; valid values are 'fast', 'traditional' and 'auto' (default: auto)])],
  49                     [],
  50                     [with_syscall=auto])
  51         AC_MSG_RESULT([$with_syscall])
  52
  53         case x"$with_syscall" in
  54             (xauto)
  55                 AC_CACHE_CHECK([which syscall(2) invocation works], [ensc_cv_test_syscall],
  56                                [
  57                                 AC_LANG_PUSH(C)
  58                                 AC_COMPILE_IFELSE(AC_LANG_SOURCE([
  59 #include "$srcdir/lib/syscall-wrap.h"
  60 #include <errno.h>
  61
  62 #define __NR_foo0       300
  63 #define __NR_foo1       301
  64 #define __NR_foo2       302
  65 #define __NR_foo3       303
  66 #define __NR_foo4       304
  67 #define __NR_foo5       305
  68 inline static _syscall0(int, foo0)
  69 inline static _syscall1(int, foo1, int, a)
  70 inline static _syscall2(int, foo2, int, a, int, b)
  71 inline static _syscall3(int, foo3, int, a, int, b, int, c)
  72 inline static _syscall4(int, foo4, int, a, int, b, int, c, int, d)
  73 inline static _syscall5(int, foo5, int, a, int, b, int, c, int, d, int, e)
  74
  75 int main() {
  76   return foo0() || \
  77          foo1(1) || \
  78          foo2(1,2) || \
  79          foo3(1,2,3) || \
  80          foo4(1,2,3,4) || \
  81          foo5(1,2,3,4,5);
  82 }
  83                                 ]),
  84                                 [ensc_cv_test_syscall=fast],
  85                                 [ensc_cv_test_syscall=traditional])
  86
  87                                 AC_LANG_POP
  88                 ])
  89                 with_syscall=$ensc_cv_test_syscall
  90                 ;;
  91             (xfast|xtraditional)
  92                 ;;
  93             *)
  94                 AC_MSG_ERROR(['$with_syscall' is not a valid value for '--with-syscall'])
  95                 ;;
  96         esac
  97
  98         if test x"$with_syscall $ensc_use_alternative_syscall_macros" = 'xfast yes'; then
  99             with_syscall='alternative'
 100         fi
 101
 102         if test x"$with_syscall" = xtraditional; then
 103             AC_DEFINE(ENSC_SYSCALL_TRADITIONAL,  1, [Define to 1 when the fast syscall(2) invocation does not work])
 104         fi
 105
 106         AH_BOTTOM([
 107 #if defined(__pic__) && defined(__i386) && !defined(ENSC_SYSCALL_TRADITIONAL)
 108 #  define ENSC_SYSCALL_TRADITIONAL      1
 109 #endif])
 110 ])