Merge branch 'lukeshu/json'

1 files changed, 48 insertions, 0 deletions

diff --git a/lib/jsonutil/binstruct.go b/lib/jsonutil/binstruct.go
new file mode 100644
index 0000000..7f4bd3f
--- /dev/null
+++ b/lib/jsonutil/binstruct.go
@@ -0,0 +1,48 @@
+// Copyright (C) 2023  Luke Shumaker <lukeshu@lukeshu.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package jsonutil
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+
+	"git.lukeshu.com/go/lowmemjson"
+
+	"git.lukeshu.com/btrfs-progs-ng/lib/binstruct"
+	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
+)
+
+type Binary[T any] struct {
+	Val T
+}
+
+var (
+	_ lowmemjson.Encodable = Binary[int]{}
+	_ lowmemjson.Decodable = (*Binary[int])(nil)
+)
+
+func (o Binary[T]) EncodeJSON(w io.Writer) error {
+	bs, err := binstruct.Marshal(o.Val)
+	if err != nil {
+		return err
+	}
+	return EncodeSplitHexString(w, bs, textui.Tunable(80))
+}
+
+func (o *Binary[T]) DecodeJSON(r io.RuneScanner) error {
+	var buf bytes.Buffer
+	if err := DecodeSplitHexString(r, &buf); err != nil {
+		return err
+	}
+	n, err := binstruct.Unmarshal(buf.Bytes(), &o.Val)
+	if err != nil {
+		return err
+	}
+	if n < buf.Len() {
+		return fmt.Errorf("%d bytes of garbage after value", n-buf.Len())
+	}
+	return nil
+}