Vendor used libs

vendor/github.com/ulikunitz/xz/lzma/operation.go

@@ -0,0 +1,55 @@
+// Copyright 2014-2022 Ulrich Kunitz. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package lzma
+
+import (
+	"fmt"
+	"unicode"
+)
+
+// operation represents an operation on the dictionary during encoding or
+// decoding.
+type operation interface {
+	Len() int
+}
+
+// rep represents a repetition at the given distance and the given length
+type match struct {
+	// supports all possible distance values, including the eos marker
+	distance int64
+	// length
+	n int
+}
+
+// Len returns the number of bytes matched.
+func (m match) Len() int {
+	return m.n
+}
+
+// String returns a string representation for the repetition.
+func (m match) String() string {
+	return fmt.Sprintf("M{%d,%d}", m.distance, m.n)
+}
+
+// lit represents a single byte literal.
+type lit struct {
+	b byte
+}
+
+// Len returns 1 for the single byte literal.
+func (l lit) Len() int {
+	return 1
+}
+
+// String returns a string representation for the literal.
+func (l lit) String() string {
+	var c byte
+	if unicode.IsPrint(rune(l.b)) {
+		c = l.b
+	} else {
+		c = '.'
+	}
+	return fmt.Sprintf("L{%c/%02x}", c, l.b)
+}