feat: initial goget release — modern IPv6-first download utility

internal/compression/lzw.go

@@ -0,0 +1,52 @@
+//go:build linux || freebsd
+// +build linux freebsd
+
+package compression
+
+import (
+	"compress/lzw"
+	"io"
+)
+
+const lzwLitWidth = 8
+
+type lzwDecompressor struct {
+	*BaseDecompressor
+	order lzw.Order
+}
+
+func NewLzwDecompressor() *lzwDecompressor { return NewLzwDecompressorWithOrder(lzw.LSB) }
+
+func NewLzwDecompressorWithOrder(order lzw.Order) *lzwDecompressor {
+	name := "lzw"
+	if order == lzw.MSB {
+		name = "lzw-msb"
+	}
+	return &lzwDecompressor{NewBaseDecompressor(name, []string{}, []string{".z", ".lzw"}), order}
+}
+
+func (l *lzwDecompressor) Reader(r io.Reader) (io.ReadCloser, error) {
+	return lzw.NewReader(r, l.order, lzwLitWidth), nil
+}
+
+type lzwCompressor struct {
+	name  string
+	order lzw.Order
+}
+
+func NewLzwCompressor() *lzwCompressor { return NewLzwCompressorWithOrder(lzw.LSB) }
+func NewLzwCompressorWithOrder(order lzw.Order) *lzwCompressor {
+	name := "lzw"
+	if order == lzw.MSB {
+		name = "lzw-msb"
+	}
+	return &lzwCompressor{name: name, order: order}
+}
+
+func (l *lzwCompressor) Name() string { return l.name }
+
+func (l *lzwCompressor) Writer(w io.Writer) (io.WriteCloser, error) {
+	return lzw.NewWriter(w, l.order, lzwLitWidth), nil
+}
+
+func init() { Register(NewLzwDecompressor()) }