(powsershell): Add logoff script.

Documents/PowerShell/logoff.ps1

@@ -0,0 +1,126 @@
+#
+# This background job automatically locks your Workstation after a specified amount of
+# time. It will come in handy if you cannot access the screensaver settings due to policy
+# restriction but want to lock your screen after a idle timeout. Or you could just
+# press [Win]+[L] everytime you leave your desk ;) .
+#
+# start with
+#       powershell.exe -windowstylpowee hidden -executionpolicy Unrestricted P:\ATH\TO\logoff.ps1
+#
+# `-windowstyle hidden` will make your PowerShell disappear/run in background
+# `-executionpolicy Unrestricted` will enable this PowerShell process to allow non-signed scripts
+#
+
+# This is the only setting: How long before locking?
+# Alternative Options:
+# * -Seconds 10 ( = 10 Seconds)
+# * -Minutes 10 ( = 10 Minutes)
+# * -Hours 10 ( = 10 Hours)
+#
+$idle_timeout = New-TimeSpan -Minutes 30
+$switch_timeout = New-TimeSpan -Minutes 4
+$untouched = New-TimeSpan -Minutes 0
+
+$touch_date = (Get-Date)
+$touch_span = New-TimeSpan -Milliseconds 500
+
+# DO NOT CHANGE ANYTHING BELOW THIS LINE
+####################################################################################################################################################################
+
+# This snippet is from http://stackoverflow.com/a/15846912
+Add-Type @'
+using System;
+using System.Diagnostics;
+using System.Runtime.InteropServices;
+
+namespace PInvoke.Win32 {
+
+    public static class UserInput {
+
+        [DllImport("user32.dll", SetLastError=false)]
+        private static extern bool GetLastInputInfo(ref LASTINPUTINFO plii);
+
+        [StructLayout(LayoutKind.Sequential)]
+        private struct LASTINPUTINFO {
+            public uint cbSize;
+            public int dwTime;
+        }
+
+        public static DateTime LastInput {
+            get {
+                DateTime bootTime = DateTime.UtcNow.AddMilliseconds(-Environment.TickCount);
+                DateTime lastInput = bootTime.AddMilliseconds(LastInputTicks);
+                return lastInput;
+            }
+        }
+
+        public static TimeSpan IdleTime {
+            get {
+                return DateTime.UtcNow.Subtract(LastInput);
+            }
+        }
+
+        public static int LastInputTicks {
+            get {
+                LASTINPUTINFO lii = new LASTINPUTINFO();
+                lii.cbSize = (uint)Marshal.SizeOf(typeof(LASTINPUTINFO));
+                GetLastInputInfo(ref lii);
+                return lii.dwTime;
+            }
+        }
+    }
+}
+'@
+#End snippet
+
+Add-Type -AssemblyName System.Windows.Forms
+
+# Helper: Is currently locked?
+$locked = 0;
+
+do {
+        # 1st: How long is your computer currently idle?
+        $idle_time = [PInvoke.Win32.UserInput]::IdleTime
+        $now = Get-Date
+
+        # Switch Window only if timeout reached
+        if (($locked -eq 0) -And ($idle_time -gt $switch_timeout)) {
+                Write-Host (Get-Date -Format HH:mm:ss) -ForegroundColor Green -NoNewline
+                $sleep_in = $idle_timeout - $idle_time
+
+                # Elapsed since last auto touch
+                $diff = New-Timespan -Start $touch_date -End $now
+
+                if (($diff - $idle_time) -lt $touch_span) {
+                        $untouched += $idle_time
+                } else {
+                        $untouched = $idle_time
+                }
+
+                Write-Host " Idle for $idle_time, touched at $touch_date ($diff ago), untouched since $untouched"
+                $touch_date = Get-Date
+
+                [System.Windows.Forms.SendKeys]::SendWait("%{TAB}")
+        }
+
+        # Your computer is not locked, but idle time is longer than allowed? -> Lock it!
+        if (($locked -eq 0) -And ($untouched -gt $idle_timeout)) {
+                # Lock it
+                rundll32.exe user32.dll,LockWorkStation
+
+                # Setting $locked to 1 will prevent it from relocking every 10 seconds
+                $locked = 1;
+                $untouched = New-Timespan -Seconds 0;
+                Write-Host ("Locking");
+        }
+
+        # Your computer is idle for less than the allowed time -> in most cases this means it is unlocked and
+        # therefore ready to be locked again!
+        if ($idle_time -lt $idle_timeout) {
+                $locked = 0;
+        }
+
+        # Save the environment. Don't use 100% of a single CPU just for idle checking :)
+    Start-Sleep -Seconds 10
+}
+while (1 -eq 1)