add libubootenv package

pkgs/default.nix

@@ -104,4 +104,6 @@ in {
   anoia = callPackage ./anoia {};
 
   levitate = callPackage ./levitate {};
+
+  libubootenv = callPackage ./libubootenv {};
 }

pkgs/libubootenv/Makefile

@@ -0,0 +1,6 @@
+CFLAGS=$(INC) -D_LINUX_TYPES_H -D_LINUX_STRING_H_
+
+fw_printenv: fw_env_main.o fw_env.o \
+        crc32.o ctype.o linux_string.o \
+        env_attr.o env_flags.o
+	$(CC) -o $@ $^

pkgs/libubootenv/default.nix

@@ -0,0 +1,17 @@
+{ stdenv
+, cmake
+, zlib
+, libyaml
+, fetchFromGitHub
+} :
+stdenv.mkDerivation {
+  name = "libubootenv";
+  src = fetchFromGitHub {
+    owner = "sbabic";
+    repo = "libubootenv";
+    rev = "3f4d15e36ceb58085b08dd13f3f2788e9299877b"; # v0.3.5
+    hash = "sha256-i7gUb1A6FTOBCpympQpndhOG9pCDA4P0iH7ZNBqo+PA=";
+  };
+  buildInputs = [ zlib libyaml ];
+  nativeBuildInputs = [ cmake ];
+}