libgsm 1.0.13

Closes Homebrew/homebrew#20688.

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

Formula/libgsm.rb

@@ -0,0 +1,39 @@
+require 'formula'
+
+class Libgsm < Formula
+  homepage 'http://www.quut.com/gsm/'
+  url 'http://www.quut.com/gsm/gsm-1.0.13.tar.gz'
+  sha1 '668b0a180039a50d379b3d5a22e78da4b1d90afc'
+
+  option :universal
+
+  def patches
+    # Builds a dynamic library for gsm, this package is no longer developed
+    # upstream. Patch taken from Debian and modified to build a dylib.
+    'https://gist.github.com/dholm/5840964/raw/'
+  end
+
+  def install
+    ENV.universal_binary if build.universal?
+    ENV.append_to_cflags '-c -O2 -DNeedFunctionPrototypes=1'
+
+    # Only the targets for which a directory exists will be installed
+    bin.mkpath
+    lib.mkpath
+    include.mkpath
+    man1.mkpath
+    man3.mkpath
+
+    # Dynamic library must be built first
+    system "make", "lib/libgsm.1.0.13.dylib",
+           "CC=#{ENV.cc}", "CCFLAGS=#{ENV.cflags}",
+           "LDFLAGS=#{ENV.ldflags}"
+    system "make", "all",
+           "CC=#{ENV.cc}", "CCFLAGS=#{ENV.cflags}",
+           "LDFLAGS=#{ENV.ldflags}"
+    system "make", "install",
+           "INSTALL_ROOT=#{prefix}",
+           "GSM_INSTALL_INC=#{include}"
+    lib.install Dir['lib/*dylib']
+  end
+end