[gdm] autogoo: make udev rules dir configurable

[Ray Strode <halfline src gnome org>]

commit ef231c2790e7a3bbee3f09ac4a125e28e95011b4
Author: Bin Li <bin li canonical com>
Date:   Mon Sep 3 22:46:48 2018 +0800

    autogoo: make udev rules dir configurable
    
    Different distributions place udev rules in
    different locations (depending on whether or
    not /usr is a symlink to /)
    
    That means the location needs to be configurable.
    
    This commit adds a new ./configure argument,
    --with-udevdir that allows distributions to specify
    where udev looks for its data files.
    
    By default it pulls the answer from pkg-config.
    
    This commit also fixes `make distcheck` when run
    by an unprivileged user by disabling udev rule
    installation entirely during distcheck.
    
    Small changes by Ray Strode.
    
    Closes https://gitlab.gnome.org/GNOME/gdm/merge_requests/44

 Makefile.am      |  2 +-
 configure.ac     | 11 ++++++++++-
 data/Makefile.am |  4 +++-
 3 files changed, 14 insertions(+), 3 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 1b710098..7896f59d 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -30,4 +30,4 @@ EXTRA_DIST = \
 DISTCLEANFILES = \
        $(NULL)
 
-AM_DISTCHECK_CONFIGURE_FLAGS = --enable-split-authentication --enable-introspection 
--without-systemdsystemunitdir
+AM_DISTCHECK_CONFIGURE_FLAGS = --enable-split-authentication --enable-introspection 
--without-systemdsystemunitdir --without-udevdir
diff --git a/configure.ac b/configure.ac
index 1a25c808..bba96d2b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -254,7 +254,10 @@ AC_ARG_WITH(tcp-wrappers,
                            [Use TCP Wrappers @<:@default=auto@:>@]),,
             with_tcp_wrappers=auto)
 
-
+AC_ARG_WITH([udevdir],
+            AS_HELP_STRING([--with-udevdir=DIR],
+                           [Directory for udev files]),
+                [with_udevdir=$withval], [with_udevdir=$($PKG_CONFIG --variable=udevdir udev)])
 AC_ARG_WITH([systemdsystemunitdir],
             AS_HELP_STRING([--with-systemdsystemunitdir=DIR],
                            [Directory for systemd service files]),
@@ -867,6 +870,11 @@ AC_PATH_PROG(SYSTEMD_X_SERVER, systemd-multi-seat-x, [/lib/systemd/systemd-multi
 AC_SUBST(SYSTEMD_X_SERVER)
 AC_DEFINE_UNQUOTED(SYSTEMD_X_SERVER,"$SYSTEMD_X_SERVER",[Path to systemd X server wrapper])
 
+if test "x$with_udevdir" != xno; then
+        AC_SUBST(UDEV_DIR, [$with_udevdir])
+fi
+AM_CONDITIONAL(INSTALL_UDEV_RULES, test x$with_udevdir != xno)
+
 if test "x$with_systemdsystemunitdir" != xno; then
         AC_SUBST(SYSTEMD_SYSTEM_UNIT_DIR, [$with_systemdsystemunitdir])
 fi
@@ -1517,6 +1525,7 @@ echo \
         XDMCP support:            ${XDMCP_SUPPORT}
         SELinux support:          ${use_selinux}
         systemd unit dir:         ${with_systemdsystemunitdir}
+        udev dir:                 ${with_udevdir}
         plymouth support:         ${use_plymouth}
         wayland support:          ${enable_wayland_support}
         Build with RBAC:          ${msg_rbac_shutdown}
diff --git a/data/Makefile.am b/data/Makefile.am
index 7c6a2eb3..162074f1 100644
--- a/data/Makefile.am
+++ b/data/Makefile.am
@@ -154,8 +154,10 @@ if ENABLE_ARCH_PAM_CONFIG
 pam_files = $(pam_arch_files)
 endif
 
-udevrulesdir = /lib/udev/rules.d
+if INSTALL_UDEV_RULES
+udevrulesdir = $(UDEV_DIR)/rules.d
 udevrules_DATA = 61-gdm.rules
+endif
 
 EXTRA_DIST += $(srcdir)/61-gdm.rules.in
 61-gdm.rules: $(srcdir)/61-gdm.rules.in