Move to x11/ in preparation for merge into new dotfiles repository

[config/dotfiles.git] / x11 / bin / xlockscreen

diff --git a/x11/bin/xlockscreen b/x11/bin/xlockscreen
new file mode 100755 (executable)
index 0000000..11b8aec
--- /dev/null
+++ b/x11/bin/xlockscreen
@@ -0,0 +1,106 @@
+#!/bin/sh
+
+# Helper script to start/lock the screen with an available screen locker.
+
+# Copyright (C) 2015  Simon Ruderich
+#
+# 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
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+set -eu
+
+
+usage() {
+    printf 'usage: %s start <lock time (min)> <lock binary>\n' "$0"
+    printf '       %s lock\n' "$0"
+    exit 1
+}
+
+installed() {
+    type "$1" >/dev/null 2>&1
+}
+
+
+if test $# -eq 0; then
+    usage
+fi
+
+if test x"$1" = xstart; then
+    if test $# -ne 3; then
+        usage
+    fi
+    lock_time_minutes="$2"
+    lock_binary="$3"
+
+    # NOTE: We must redirect stdout of the spawned background processes to
+    # /dev/null or a potential caller which uses our output will wait forever
+    # on the inherited stdin (and we become a zombie)! Thanks to Beano on [1]
+    # for the idea, read on 2015-08-23.
+    #
+    # [1]: https://stackoverflow.com/questions/3748432/insane-crond-behavior-keeps-making-defunct-bash-processes/3750028#3750028
+
+    if installed xscreensaver; then
+        printf 'xscreensaver.timeout: %d
+                xscreensaver.lock: True
+                xscreensaver.lockTimeout: 0
+               ' "$lock_time_minutes" | xrdb -merge
+        xscreensaver >/dev/null &
+        echo xscreensaver
+    elif installed xautolock; then
+        if installed "$lock_binary"; then
+            # Terminate a running xautolock because we might have to replace
+            # its timeout and other settings with our values.
+            pkill -u "$USER" xautolock || true
+
+            xautolock -secure -time "$lock_time_minutes" \
+                      -locker "$lock_binary" \
+                      >/dev/null &
+            echo xautolock
+        else
+            echo "Locker '$lock_binary' not installed. Auto lock won't work!"
+            exit 1
+        fi
+    else
+        echo "No locker found. Auto lock won't work!"
+        exit 1
+    fi
+
+elif test x"$1" = xlock; then
+    if test $# -ne 1; then
+        usage
+    fi
+
+    if installed xscreensaver; then
+        # Start xscreensaver if it's not already running. xscreensaver-command
+        # ensures xscreensaver is available for the current X session.
+        xscreensaver-command -time >/dev/null 2>&1 || xscreensaver &
+
+        # It can take a while for xscreensaver to start, wait until it's
+        # ready. a || b && c behaves like (a || b) && c.
+        while :; do
+            xscreensaver-command -lock || test $? -ne 255 && break
+        done
+    elif installed xtrlock; then
+        # Sleep is necessary to allow xtrlock to grab the keyboard input.
+        sleep 1
+        exec xtrlock
+    elif installed xlock; then
+        exec xlock
+    else
+        echo 'No screen locker found!'
+        exit 1
+    fi
+
+else
+    usage
+fi