[PATCH] Update xflock4 (Bug 10217) again

[Alexander Mezin]

Based on patch by Jarno Suni.

- Use pgrep instead of pidof, which is, hopefully, available
everywhere.
- Check screensavers running under current uid only.
- Do not redirect output of lock commands to /dev/null. It could
be useful for diagnostics.
---
 scripts/xflock4 | 70 ++++++++++++++++++++++++++++++++++++---------------------
 1 file changed, 44 insertions(+), 26 deletions(-)

diff --git a/scripts/xflock4 b/scripts/xflock4
index ec4d05d..9580683 100644
--- a/scripts/xflock4
+++ b/scripts/xflock4
@@ -4,7 +4,7 @@
 #
 #  Copyright (C) 1999, 2003 Olivier Fourdan (fourdan at xfce.org)
 #  Copyright (C) 2011       Guido Berhoerster (guido+xfce.org at berhoerster.name)
-#  Copyright (C) 2011       Jarno Suni (8 at iki.fi)
+#  Copyright (C) 2014       Jarno Suni (8 at iki.fi)
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
@@ -20,31 +20,49 @@
 #  along with this program; if not, write to the Free Software
 #  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 #
-
-PATH=/bin:/usr/bin
+set -o nounset
+set -o errexit
+# OpenBSD and possibly some other OSs require
+# /usr/local/bin:/usr/X11R6/bin in PATH
+PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
 export PATH
 
-# Lock by xscreensaver or gnome-screensaver, if a respective daemon is running
-for lock_cmd in \
-    "xscreensaver-command -lock" \
-    "gnome-screensaver-command --lock"
-do
-    $lock_cmd >/dev/null 2>&1 && exit
-done
-
-# else run another access locking utility, if installed
-for lock_cmd in \
-  "xlock -mode blank" \
-  "slock"
-  do
-    set -- $lock_cmd
-    if command -v -- $1 >/dev/null 2>&1; then
-        $lock_cmd >/dev/null 2>&1 &
-	# turn off display backlight:
-	xset dpms force off
-        exit
-    fi
-done
+check_running() {
+    pgrep -U `id -u` -x $1 >/dev/null 2>&1
+}
 
-# else access locking failed
-exit 1
+# Lock by a screensaver, if its daemon is running.
+if check_running xscreensaver; then
+    xscreensaver-command -lock
+elif check_running gnome-screensaver; then
+    gnome-screensaver-command --lock
+elif check_running light-locker; then
+    light-locker-command --lock
+elif check_running mate-screensaver; then
+    mate-screensaver-command --lock
+elif check_running cinnamon-screensaver; then
+    cinnamon-screensaver-command --lock
+elif check_running xautolock; then
+# Note: xautolock does not tell, if it succeeds in locking,
+# so be sure to start the daemon properly.
+    xautolock -locknow
+# No daemon was found; use some available utility to lock:
+elif command -v i3lock >/dev/null 2>&1; then
+    i3lock --dpms --color=000000
+else
+ for lock_cmd in \
+    "xlock -mode blank" \
+    "slock" \
+    "slimlock"
+ do
+  if command -v -- $lock_cmd >/dev/null 2>&1; then
+     # Run the command in background
+     $lock_cmd &
+     # Turn off display backlight
+     xset dpms force off
+     exit
+  fi
+ done
+ # None of the above worked. Access locking failed.
+ exit 1
+fi
-- 
2.3.3