uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/pkgs-lib/formats/java-properties/default.nix

@@ -0,0 +1,132 @@
+{ lib, pkgs }:
+let
+  inherit (lib) types;
+  inherit (types) attrsOf oneOf coercedTo str bool int float package;
+in
+{
+  javaProperties = { comment ? "Generated with Nix", boolToString ? lib.boolToString }: {
+
+    # Design note:
+    # A nested representation of inevitably leads to bad UX:
+    # 1. keys like "a.b" must be disallowed, or
+    #    the addition of options in a freeformType module
+    #    become breaking changes
+    # 2. adding a value for "a" after "a"."b" was already
+    #    defined leads to a somewhat hard to understand
+    #    Nix error, because that's not something you can
+    #    do with attrset syntax. Workaround: "a"."", but
+    #    that's too little too late. Another workaround:
+    #    mkMerge [ { a = ...; } { a.b = ...; } ].
+    #
+    # Choosing a non-nested representation does mean that
+    # we sacrifice the ability to override at the (conceptual)
+    # hierarchical levels, _if_ an application exhibits those.
+    #
+    # Some apps just use periods instead of spaces in an odd
+    # mix of attempted categorization and natural language,
+    # with no meaningful hierarchy.
+    #
+    # We _can_ choose to support hierarchical config files
+    # via nested attrsets, but the module author should
+    # make sure that problem (2) does not occur.
+    type = let
+      elemType =
+        oneOf ([
+          # `package` isn't generalized to `path` because path values
+          # are ambiguous. Are they host path strings (toString /foo/bar)
+          # or should they be added to the store? ("${/foo/bar}")
+          # The user must decide.
+          (coercedTo package toString str)
+
+          (coercedTo bool boolToString str)
+          (coercedTo int toString str)
+          (coercedTo float toString str)
+        ])
+        // { description = "string, package, bool, int or float"; };
+      in attrsOf elemType;
+
+    generate = name: value:
+      pkgs.runCommandLocal name
+        {
+          # Requirements
+          # ============
+          #
+          #  1. Strings in Nix carry over to the same
+          #     strings in Java => need proper escapes
+          #  2. Generate files quickly
+          #      - A JVM would have to match the app's
+          #        JVM to avoid build closure bloat
+          #      - Even then, JVM startup would slow
+          #        down config generation.
+          #
+          #
+          # Implementation
+          # ==============
+          #
+          # Escaping has two steps
+          #
+          # 1. jq
+          #    Escape known separators, in order not
+          #    to break up the keys and values.
+          #    This handles typical whitespace correctly,
+          #    but may produce garbage for other control
+          #    characters.
+          #
+          # 2. iconv
+          #    Escape >ascii code points to java escapes,
+          #    as .properties files are supposed to be
+          #    encoded in ISO 8859-1. It's an old format.
+          #    UTF-8 behavior may exist in some apps and
+          #    libraries, but we can't rely on this in
+          #    general.
+
+          passAsFile = [ "value" ];
+          value = builtins.toJSON value;
+          nativeBuildInputs = [
+            pkgs.jq
+            pkgs.libiconvReal
+          ];
+
+          jqCode =
+            let
+              main = ''
+                to_entries
+                  | .[]
+                  | "\(
+                      .key
+                      | ${commonEscapes}
+                      | gsub(" "; "\\ ")
+                      | gsub("="; "\\=")
+                    ) = \(
+                      .value
+                      | ${commonEscapes}
+                      | gsub("^ "; "\\ ")
+                      | gsub("\\n "; "\n\\ ")
+                    )"
+              '';
+              # Most escapes are equal for both keys and values.
+              commonEscapes = ''
+                gsub("\\\\"; "\\\\")
+                | gsub("\\n"; "\\n\\\n")
+                | gsub("#"; "\\#")
+                | gsub("!"; "\\!")
+                | gsub("\\t"; "\\t")
+                | gsub("\r"; "\\r")
+              '';
+            in
+            main;
+
+          inputEncoding = "UTF-8";
+
+          inherit comment;
+
+        } ''
+        (
+          echo "$comment" | while read -r ln; do echo "# $ln"; done
+          echo
+          jq -r --arg hash '#' "$jqCode" "$valuePath" \
+            | iconv --from-code "$inputEncoding" --to-code JAVA \
+        ) > "$out"
+      '';
+  };
+}