cramfsswap: Make binary available

Signed-off-by: Pamplemousse <[e-mail]>

pkgs/os-specific/linux/cramfsswap/builder.sh

···
-source $stdenv/setup
-
-export DESTDIR=$out
-mkdir -p $out/usr/bin
-
-genericBuild

pkgs/os-specific/linux/cramfsswap/default.nix

···
 {stdenv, fetchurl, zlib}:
 
-stdenv.mkDerivation {
-  name = "cramfsswap-1.4.1";
-  builder = ./builder.sh;
+stdenv.mkDerivation rec {
+  pname = "cramfsswap";
+  version = "1.4.1";
+
   src = fetchurl {
-    url = "mirror://debian/pool/main/c/cramfsswap/cramfsswap_1.4.1.tar.gz";
+    url = "mirror://debian/pool/main/c/cramfsswap/${pname}_${version}.tar.gz";
     sha256 = "0c6lbx1inkbcvvhh3y6fvfaq3w7d1zv7psgpjs5f3zjk1jysi9qd";
   };
 
   buildInputs = [zlib];
 
+  installPhase = ''
+    install --target $out/bin -D cramfsswap
+  '';
+
   meta = with stdenv.lib; {
-    description = "swap endianess of a cram filesystem (cramfs)";
+    description = "Swap endianess of a cram filesystem (cramfs)";
     homepage = "https://packages.debian.org/sid/utils/cramfsswap";
     license = licenses.gpl2;
     platforms = platforms.linux;