CFitsIO: Add option to install example programs

Added the option --with-examples to the cfitsio formula, that downloads,
compiles and installs some useful programs, like listhead, modhead, etc.

Signed-off-by: Charlie Sharpsteen <source@sharpsteen.net>

Formula/cfitsio.rb

@@ -1,15 +1,44 @@
 require 'formula'
 
+class CfitsioExamples < Formula
+  url 'http://heasarc.gsfc.nasa.gov/docs/software/fitsio/cexamples/cexamples.zip'
+  md5 '31a5f5622a111f25bee5a3fda2fdac28'
+  version '2010.08.19'
+end
+
 class Cfitsio < Formula
   url 'ftp://heasarc.gsfc.nasa.gov/software/fitsio/c/cfitsio3280.tar.gz'
   homepage 'http://heasarc.gsfc.nasa.gov/docs/software/fitsio/fitsio.html'
   md5 'fdb9c0f51678b47e78592c70fb5dc793'
   version '3.28'
 
+  def options
+    [
+     ['--with-examples', "Compile and install example programs from http://heasarc.gsfc.nasa.gov/docs/software/fitsio/cexamples.html as well as fpack and funpack"]
+    ]
+  end
+
   def install
     # --disable-debug and --disable-dependency-tracking are not recognized by configure
     system "./configure", "--prefix=#{prefix}"
     system "make shared"
     system "make install"
+
+    if ARGV.include? '--with-examples'
+      system "make fpack funpack"
+      bin.install ['fpack', 'funpack']
+
+      # fetch, compile and install examples programs
+      CfitsioExamples.new.brew do
+        mkdir 'bin'
+        Dir.glob('*.c').each do |f|
+          # compressed_fits.c does not work (obsolete function call)
+          if f != 'compress_fits.c'
+            system "#{ENV.compiler} #{f} -I#{include} -L#{lib} -lcfitsio -lm -o bin/#{f.sub('.c','')}"
+          end
+        end
+        bin.install Dir['bin/*']
+      end
+    end
   end
 end