tuntaposx 20111101

Closes Homebrew/homebrew#16311.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

Formula/tuntap.rb

@@ -0,0 +1,47 @@
+require 'formula'
+
+def kext_prefix
+  prefix/'Library/Extensions'
+end
+
+class Tuntap < Formula
+  homepage 'http://tuntaposx.sourceforge.net/'
+  url 'git://git.code.sf.net/p/tuntaposx/code', :tag => 'release_20111101'
+  version '20111101'
+
+  def install
+    ENV.j1 # to avoid race conditions (can't open: ../tuntap.o)
+    cd 'tuntap' do
+      system "make"
+      kext_prefix.install "tun.kext", "tap.kext"
+      prefix.install "startup_item/tap", "startup_item/tun"
+    end
+  end
+
+  def caveats
+    message = <<-EOS.undent
+      In order for TUN/TAP network devices to work, the tun/tap kernel extensions
+      must be installed by the root user:
+
+        sudo cp -pR #{kext_prefix}/tap.kext /Library/Extensions/
+        sudo cp -pR #{kext_prefix}/tun.kext /Library/Extensions/
+        sudo chown -R root:wheel /Library/Extensions/tap.kext
+        sudo chown -R root:wheel /Library/Extensions/tun.kext
+        sudo touch /Library/Extensions/
+
+      To load the extensions at startup, you have to install those scripts too:
+
+        sudo cp -pR #{prefix}/tap /Library/StartupItems/
+        sudo cp -pR #{prefix}/tun /Library/StartupItems/
+
+      If upgrading from a previous version of tuntap, the old kernel extension
+      will need to be unloaded before performing the steps listed above. First,
+      check that no tunnel is being activated, disconnect them all and then unload
+      the kernel extension:
+
+        sudo kextunload -b foo.tun
+        sudo kextunload -b foo.tap
+
+    EOS
+  end
+end