3 files changed, 91 insertions, 0 deletions
diff --git a/pkgs/simple/xdpytools/default.nix b/pkgs/simple/xdpytools/default.nix
new file mode 100644
index 0000000..7d1ee07
--- /dev/null
+++ b/pkgs/simple/xdpytools/default.nix
@@ -0,0 +1,31 @@
+{ lib, pkgs }:
+
+let
+  install = name: { path }: /* sh */ ''
+    (
+      mkdir -p $out/bin
+      touch $out/bin/${name}
+      chmod +x $out/bin/${name}
+      exec >$out/bin/${name}
+
+      echo '#! ${pkgs.dash}/bin/dash'
+      echo export PATH=${lib.makeBinPath path}
+      sed 1d ${./src + "/${name}"}
+    )
+  '';
+in
+
+pkgs.runCommand "xdpytools" {}
+  (toString
+    (lib.mapAttrsToList install {
+      xdpychvt.path = [
+        "$out"
+        "/run/wrappers/'$LOGNAME'"
+        "/run/wrappers"
+      ];
+      xdpysel.path = [
+        "$out"
+        pkgs.findutils
+        pkgs.jq
+      ];
+    }))
diff --git a/pkgs/simple/xdpytools/src/xdpychvt b/pkgs/simple/xdpytools/src/xdpychvt
new file mode 100755
index 0000000..84c1907
--- /dev/null
+++ b/pkgs/simple/xdpytools/src/xdpychvt
@@ -0,0 +1,11 @@
+#! /bin/sh
+# usage: xdpychvt {prev,next}
+# Changes to the VT based on the selected X display.
+#
+# This allows switching between X servers when display names and VT numbers
+# correlate.  A more sophisticated tool would try to determine the correct VT
+# by e.g. looking at /proc, but this might not possible when e.g.  using
+# security.hideProcessInformation.
+#
+
+chvt "$(xdpysel "$1")"
diff --git a/pkgs/simple/xdpytools/src/xdpysel b/pkgs/simple/xdpytools/src/xdpysel
new file mode 100755
index 0000000..e080155
--- /dev/null
+++ b/pkgs/simple/xdpytools/src/xdpysel
@@ -0,0 +1,49 @@
+#! /bin/sh
+# usage: xdpysel {prev,next}
+# Print the number of the selected X display.
+
+find /tmp/.X11-unix -mindepth 1 -maxdepth 1 |
+jq -Rrs --arg command "$1" '
+  (
+    split("\n") |
+    map(
+      select(.!="") |
+      match("^.*/X([0-9]+)$").captures[0].string |
+      tonumber
+    )
+  )
+    as $all_displays |
+
+  (
+    env.DISPLAY |
+    match("^:([0-9]+)(?:[.][0-9]+)?$").captures[0].string |
+    tonumber
+  )
+    as $current_display |
+
+  ($all_displays | length) as $all_displays_count |
+
+  ($all_displays|index($current_display))
+    as $current_index |
+
+  (($current_index + 1) % $all_displays_count)
+    as $next_index |
+
+  (($all_displays_count + $current_index - 1) % $all_displays_count)
+    as $prev_index |
+
+  $all_displays[$prev_index] as $prev_display |
+  $all_displays[$next_index] as $next_display |
+
+  {
+    prev: $prev_display,
+    next: $next_display,
+  }[$command]
+    as $result |
+
+  if $result | type == "number" then
+    $result
+  else
+    "xdpysel: bad argument: \($command)\n" | halt_error(-1)
+  end
+'