Merge pull request #1664 from lovedheart/patch-2

Create libxshmfence.rb

packages/libxshmfence.rb

+require 'package'
+
+class Libxshmfence < Package
+  description 'A library that exposes a event API on top of Linux futexes'
+  homepage 'http://t2sde.org/packages/libxshmfence.html'
+  version '1.2'
+  source_url 'https://xorg.freedesktop.org/releases/individual/lib/libxshmfence-1.2.tar.bz2'
+  source_sha256 'd21b2d1fd78c1efbe1f2c16dae1cb23f8fd231dcf891465b8debe636a9054b0c'
+
+  def self.build
+    system './configure',
+      "--prefix=#{CREW_PREFIX}",
+      "--libdir=#{CREW_LIB_PREFIX}"
+    system 'make'
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+end