* ENSC_SYSCALL_ALTERNATIVE: added
[util-vserver.git] / util-vserver / m4 / ensc_syscall.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_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 $enable_val in
28                            (yes|no)   ensc_use_alternative_syscall_macros=$enable_val;;
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         AC_MSG_CHECKING([for syscall(2) invocation method])
45         AC_ARG_WITH([syscall],
46                     [AC_HELP_STRING([--with-syscall=METHOD],
47                                     [call syscall(2) with the specified METHOD; valid values are 'fast', 'traditional' and 'auto' (default: auto)])],
48                     [],
49                     [with_syscall=auto])
50         AC_MSG_RESULT([$with_syscall])
51         
52         case x"$with_syscall" in
53             (xauto)
54                 AC_CACHE_CHECK([which syscall(2) invocation works], [ensc_cv_test_syscall],
55                                [
56                                 AC_LANG_PUSH(C)
57                                 AC_COMPILE_IFELSE(AC_LANG_SOURCE([
58 #include "$srcdir/lib/syscall-wrap.h"
59 #include <errno.h>
60 #define __NR_foo0       300
61 #define __NR_foo1       301
62 #define __NR_foo2       302
63 #define __NR_foo3       303
64 #define __NR_foo4       304
65 #define __NR_foo5       305
66 inline static _syscall0(int, foo0)
67 inline static _syscall1(int, foo1, int, a)
68 inline static _syscall2(int, foo2, int, a, int, b)
69 inline static _syscall3(int, foo3, int, a, int, b, int, c)
70 inline static _syscall4(int, foo4, int, a, int, b, int, c, int, d)
71 inline static _syscall5(int, foo5, int, a, int, b, int, c, int, d, int, e)
72
73 int main() {
74   return foo0() || \
75          foo1(1) || \
76          foo2(1,2) || \
77          foo3(1,2,3) || \
78          foo4(1,2,3,4) || \
79          foo5(1,2,3,4,5);
80 }
81                                 ]),
82                                 [ensc_cv_test_syscall=fast],
83                                 [ensc_cv_test_syscall=traditional])
84
85                                 AC_LANG_POP
86                 ])
87                 with_syscall=$ensc_cv_test_syscall
88                 ;;
89             (xfast|xtraditional)
90                 ;;
91             *)
92                 AC_MSG_ERROR(['$with_syscall' is not a valid value for '--with-syscall'])
93                 ;;
94         esac
95
96         if test x"$with_syscall $ensc_use_alternative_syscall_macros" = 'xfast yes'; then
97             with_syscall='alternative'
98         fi
99
100         if test x"$with_syscall" = xtraditional; then
101             AC_DEFINE(ENSC_SYSCALL_TRADITIONAL,  1, [Define to 1 when the fast syscall(2) invocation does not work])
102         fi
103         
104         AH_BOTTOM([
105 #if defined(__pic__) && defined(__i386) && !defined(ENSC_SYSCALL_TRADITIONAL)
106 #  define ENSC_SYSCALL_TRADITIONAL      1
107 #endif])
108 ])