1 files changed, 21 insertions, 0 deletions
diff --git a/Library/Formula/osm2pgsql.rb b/Library/Formula/osm2pgsql.rb
index 0cf3301c2..717703a1f 100644
--- a/Library/Formula/osm2pgsql.rb
+++ b/Library/Formula/osm2pgsql.rb
@@ -1,5 +1,24 @@
 require 'formula'
 
+class PostgresqlInstalled < Requirement
+  def message; <<-EOS.undent
+    PostgresQL is required to install.
+
+    You can install this with:
+      brew install postgresql
+
+    Or you can use an official installer from:
+      http://www.postgresql.org/
+    EOS
+  end
+  def satisfied?
+    which 'pg_config'
+  end
+  def fatal?
+    true
+  end
+end
+
 class Osm2pgsql < Formula
   head 'http://svn.openstreetmap.org/applications/utils/export/osm2pgsql/', :using => :svn
   homepage 'http://wiki.openstreetmap.org/wiki/Osm2pgsql'
@@ -9,8 +28,10 @@ class Osm2pgsql < Formula
     depends_on "libtool" => :build
   end
 
+  depends_on PostgresqlInstalled.new
   depends_on "geos"
   depends_on "proj"
+  depends_on "protobuf-c" => :optional
 
   def install
     system "./autogen.sh"