Adds javalib and sawja

Javalib is a library that parses Java .class files into OCaml data
structures. Sawja is a library written in OCaml, relying on Javalib to
provide a high level representation of Java bytecode programs.

Homepage: http://sawja.inria.fr/

pkgs/development/ocaml-modules/javalib/default.nix

@@ -0,0 +1,40 @@
+{stdenv, fetchurl, which, ocaml, findlib, camlzip, extlib}:
+let
+  pname = "javalib";
+  version = "2.3";
+  webpage = "http://sawja.inria.fr/";
+  ocaml_version = (builtins.parseDrvName ocaml.name).version;
+in
+stdenv.mkDerivation rec {
+
+  name = "ocaml-${pname}-${version}";
+
+  src = fetchurl {
+    url = "https://gforge.inria.fr/frs/download.php/33090/${pname}-${version}.tar.bz2";
+    sha256 = "1i8djcanzm250mwilm3jfy37cz0k0x7jbnrz8a5vvdi91kyzh52j";
+  };
+
+  buildInputs = [ which ocaml findlib camlzip extlib ];
+
+  patches = [ ./configure.sh.patch ./Makefile.config.example.patch ];
+
+  createFindlibDestdir = true;
+
+  configureScript = "./configure.sh";
+  dontAddPrefix = "true";
+
+  preBuild = ''
+    make ptrees;
+    make installptrees;
+    export OCAMLPATH=$out/lib/ocaml/${ocaml_version}/site-lib/:$OCAMLPATH;
+  '';
+
+  propagatedBuildInputs = [ camlzip extlib ];
+
+  meta = {
+    description = "A library that parses Java .class files into OCaml data structures";
+    homepage = "${webpage}";
+    license = stdenv.lib.licenses.lgpl3;
+    platforms = ocaml.meta.platforms;
+  };
+}