[PATCH v2 app-xdm 18/19] config: replace platform check with compiler defines for SU

[Gaetan Nadon]

The intent for the platform check for SU is to use "su -m" for
BSD-like systems. The compiler already provide defines for
such systems.

Better alternatives are to perform a feature check on the behavior of "su",
or to change code in xdm-config to setuid.

For the time being, this patch will reduce maintenance by replacing
the large case statement and the Automake variable with an 
existing one liner of defines.

Signed-off-by: Gaetan Nadon <memsize at videotron.ca>
---

Seconnd edition. Commit text modified to indicate the patch is done in the hope of reducing
configuration complexity and maintenance and not for promoting one solution over another.

 config/Makefile.am    |    2 +-
 config/xdm-config.cpp |    7 ++++++-
 configure.ac          |   24 ------------------------
 3 files changed, 7 insertions(+), 26 deletions(-)

diff --git a/config/Makefile.am b/config/Makefile.am
index d13645f..c3d837f 100644
--- a/config/Makefile.am
+++ b/config/Makefile.am
@@ -54,7 +54,7 @@ CPP_FILES_FLAGS = -DBINDIR="$(bindir)" -DDEFAULTVT="$(DEFAULTVT)" \
     -DXDMDIR="$(XDMLIBDIR)" -DXDMLOGDIR="$(XDMLOGDIR)" \
     -DXDMXAUTHDIR="$(XDMXAUTHDIR)" \
     -DXDMPIDDIR="$(XDMPIDDIR)" -DXDMCONFIGDIR="$(XDMCONFIGDIR)" \
-    -DXDMSCRIPTDIR="$(XDMSCRIPTDIR)" -DSU="$(SU)" \
+    -DXDMSCRIPTDIR="$(XDMSCRIPTDIR)" \
     -DCHOOSERPATH="$(XDMLIBDIR)/chooser" $(XPMDEFINES) \
     -DSHELL_CMD="$(SHELL_CMD)" $(MKTEMP_DEFINES)
 
diff --git a/config/xdm-config.cpp b/config/xdm-config.cpp
index 59d548b..81a5931 100644
--- a/config/xdm-config.cpp
+++ b/config/xdm-config.cpp
@@ -16,7 +16,12 @@ DisplayManager.keyFile:		XDMCONFIGDIR/xdm-keys
 DisplayManager.servers:		XDMCONFIGDIR/Xservers
 DisplayManager.accessFile:	XDMCONFIGDIR/Xaccess
 DisplayManager*resources:	XDMCONFIGDIR/Xresources
-DisplayManager.willing:		SU nobody -c XDMSCRIPTDIR/Xwilling
+# if defined(__OpenBSD__) || defined(__NetBSD__) || defined(__FreeBSD__) \
+	|| defined(__APPLE__) || defined(__DragonFly__)
+DisplayManager.willing:		su -m nobody -c XDMSCRIPTDIR/Xwilling
+#else
+DisplayManager.willing:		su nobody -c XDMSCRIPTDIR/Xwilling
+#endif
 ! All displays should use authorization, but we cannot be sure
 ! X terminals may not be configured that way, so they will require
 ! individual resource settings.
diff --git a/configure.ac b/configure.ac
index 53793a1..69f251c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -145,30 +145,6 @@ if test "x$USE_SELINUX" != "xno" ; then
 	LIBS="$old_LIBS"
 fi
 
-# FIXME: Find better test for which OS'es use su -m  - for now, just try to
-# mirror the Imakefile setting of:
-# if  defined(OpenBSDArchitecture) || defined(NetBSDArchitecture) || defined(FreeBSDArchitecture) || defined(DarwinArchitecture)
-
-
-case $host_os in
-    linux*|gnu*|*-gnu)
-	SU="su"
-        ;;
-    darwin*)
-	SU="su -m"
-        ;;
-    *bsd*|dragonfly*)
-	SU="su -m"
-        ;;
-    solaris*|sysv4*)
-	SU="su"
-	;;
-    *)
-	SU="su"
-        ;;
-esac
-AC_SUBST(SU)
-
 # Check for /dev/random or /dev/urandom
 AC_ARG_WITH(random-device, 
 	AC_HELP_STRING([--with-random-device\[=<pathname>\]],
-- 
1.6.0.4