Sawfish (git): New Package

Sawfish is a versatile, Lisp-based window manager

In that commit I include all Sawfish stack:
- librep, a lisp system;
- rep-gtk, bindings for gtk
- sawfish, the window manager

pkgs/applications/window-managers/sawfish/default.nix

@@ -0,0 +1,42 @@
+{ stdenv, fetchgit, pkgconfig, which, autoreconfHook, rep-gtk, pango, gdk_pixbuf, libXinerama, libXrandr, libXtst, imlib, gettext, texinfo, makeWrapper }:
+
+with stdenv.lib;
+stdenv.mkDerivation rec {
+
+  name = "sawfish-git-2015-02-15";
+
+  src = fetchgit {
+    url = "https://github.com/SawfishWM/sawfish.git";
+    rev = "44729f44017e6779b4b66a7ecdbd63a98731f668";
+    sha256 = "bd3f42f1604f37ecb2515008341cac4f6965840b2d6a6639dd1f3f2459f68e73";
+  };
+
+  buildInputs = [ pkgconfig which autoreconfHook rep-gtk pango gdk_pixbuf libXinerama libXrandr libXtst imlib gettext texinfo makeWrapper ];
+
+  patchPhase = ''
+    sed -e 's|REP_DL_LOAD_PATH=|REP_DL_LOAD_PATH=$(REP_DL_LOAD_PATH):|g' -i Makedefs.in
+    sed -e 's|$(repexecdir)|$(libdir)/rep|g' -i src/Makefile.in
+  '';
+
+  postInstall = ''
+    for i in $out/lib/sawfish/sawfish-menu $out/bin/sawfish-about  $out/bin/sawfish-client $out/bin/sawfish-config $out/bin/sawfish; do
+      wrapProgram $i \
+        --prefix REP_DL_LOAD_PATH "$out/lib/rep" \
+	--set REP_LOAD_PATH "$out/share/sawfish/lisp"
+    done
+  '';
+  
+  meta = {
+    description = "An extensible, Lisp-based window manager";
+    longDescription = ''
+      Sawfish is an extensible window manager using a Lisp-based scripting language.
+      Its policy is very minimal compared to most window managers. Its aim is simply
+      to manage windows in the most flexible and attractive manner possible.
+      All high-level WM functions are implemented in Lisp for future extensibility
+      or redefinition.
+    '';
+    homepage = http://sawfish.wikia.com;
+    license = licenses.gpl2;
+    maintainers = [ maintainers.AndersonTorres ];
+  };
+}