added 'personality'
[util-vserver.git] / util-vserver / m4 / ensc_syscall.m4
index 8d2feed..57b1c8e 100644 (file)
@@ -17,8 +17,31 @@ dnl Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
 dnl Usage: ENSC_SYSCALL
 
+AC_DEFUN([ENSC_SYSCALL_ALTERNATIVE],
+[
+       AC_MSG_CHECKING([whether to use alternative _syscallX macros])
+       AC_ARG_ENABLE([alternative-syscalls],
+                     [AC_HELP_STRING([--disable-alternative-syscalls],
+                                     [do not use the alternative _syscallX macros
+                                      provided by Herbert Poetzl (default: use them)])],
+                     [case $enableval in
+                          (yes|no)   ensc_use_alternative_syscall_macros=$enableval;;
+                          (*)        AC_MSG_ERROR(['$enableval' is not a valid value for '--disable-alternative-syscalls']);;
+                      esac],
+                      [ensc_use_alternative_syscall_macros=yes])
+
+       case $ensc_use_alternative_syscall_macros in
+               (yes)   AC_DEFINE(ENSC_USE_ALTERNATIVE_SYSCALL_MACROS, 1, [Use alternative _syscallX macros]);;
+       esac
+
+       AC_MSG_RESULT([$ensc_use_alternative_syscall_macros])
+])
+
 AC_DEFUN([ENSC_SYSCALL],
 [
+       AC_REQUIRE([ENSC_KERNEL_HEADERS])
+       AC_REQUIRE([ENSC_SYSCALL_ALTERNATIVE])
+
         AC_MSG_CHECKING([for syscall(2) invocation method])
         AC_ARG_WITH([syscall],
                    [AC_HELP_STRING([--with-syscall=METHOD],
@@ -28,29 +51,54 @@ AC_DEFUN([ENSC_SYSCALL],
         AC_MSG_RESULT([$with_syscall])
         
         case x"$with_syscall" in
-            xauto)
+            (xauto)
                AC_CACHE_CHECK([which syscall(2) invocation works], [ensc_cv_test_syscall],
-                              [AC_COMPILE_IFELSE([
-#include <asm/unistd.h>
-#include <syscall.h>
+                              [
+                               AC_LANG_PUSH(C)
+                               AC_COMPILE_IFELSE(AC_LANG_SOURCE([
+#include "$srcdir/lib/syscall-wrap.h"
 #include <errno.h>
-#define __NR_foo       300
-inline static _syscall4(int, foo, int, a, int, b, int, c, int, d)
+
+#define __NR_foo0      300
+#define __NR_foo1      301
+#define __NR_foo2      302
+#define __NR_foo3      303
+#define __NR_foo4      304
+#define __NR_foo5      305
+inline static _syscall0(int, foo0)
+inline static _syscall1(int, foo1, int, a)
+inline static _syscall2(int, foo2, int, a, int, b)
+inline static _syscall3(int, foo3, int, a, int, b, int, c)
+inline static _syscall4(int, foo4, int, a, int, b, int, c, int, d)
+inline static _syscall5(int, foo5, int, a, int, b, int, c, int, d, int, e)
 
 int main() {
-  return foo(1,2,3,4);
+  return foo0() || \
+        foo1(1) || \
+        foo2(1,2) || \
+         foo3(1,2,3) || \
+         foo4(1,2,3,4) || \
+        foo5(1,2,3,4,5);
 }
-               ],
-               [ensc_cv_test_syscall=fast],[ensc_cv_test_syscall=traditional])])
+                               ]),
+                               [ensc_cv_test_syscall=fast],
+                               [ensc_cv_test_syscall=traditional])
+
+                               AC_LANG_POP
+               ])
                with_syscall=$ensc_cv_test_syscall
                ;;
-            xfast|xtraditional)
+            (xfast|xtraditional)
                ;;
             *)
                AC_MSG_ERROR(['$with_syscall' is not a valid value for '--with-syscall'])
                ;;
         esac
 
+       if test x"$with_syscall $ensc_use_alternative_syscall_macros" = 'xfast yes'; then
+           with_syscall='alternative'
+        fi
+
         if test x"$with_syscall" = xtraditional; then
             AC_DEFINE(ENSC_SYSCALL_TRADITIONAL,  1, [Define to 1 when the fast syscall(2) invocation does not work])
         fi