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-rw-r--r--vendor/github.com/ulikunitz/xz/lzma/properties.go69
1 files changed, 69 insertions, 0 deletions
diff --git a/vendor/github.com/ulikunitz/xz/lzma/properties.go b/vendor/github.com/ulikunitz/xz/lzma/properties.go
new file mode 100644
index 000000000..23418e25d
--- /dev/null
+++ b/vendor/github.com/ulikunitz/xz/lzma/properties.go
@@ -0,0 +1,69 @@
+// Copyright 2014-2017 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 (
+ "errors"
+ "fmt"
+)
+
+// maximum and minimum values for the LZMA properties.
+const (
+ minPB = 0
+ maxPB = 4
+)
+
+// maxPropertyCode is the possible maximum of a properties code byte.
+const maxPropertyCode = (maxPB+1)*(maxLP+1)*(maxLC+1) - 1
+
+// Properties contains the parameters LC, LP and PB. The parameter LC
+// defines the number of literal context bits; parameter LP the number
+// of literal position bits and PB the number of position bits.
+type Properties struct {
+ LC int
+ LP int
+ PB int
+}
+
+// String returns the properties in a string representation.
+func (p *Properties) String() string {
+ return fmt.Sprintf("LC %d LP %d PB %d", p.LC, p.LP, p.PB)
+}
+
+// PropertiesForCode converts a properties code byte into a Properties value.
+func PropertiesForCode(code byte) (p Properties, err error) {
+ if code > maxPropertyCode {
+ return p, errors.New("lzma: invalid properties code")
+ }
+ p.LC = int(code % 9)
+ code /= 9
+ p.LP = int(code % 5)
+ code /= 5
+ p.PB = int(code % 5)
+ return p, err
+}
+
+// verify checks the properties for correctness.
+func (p *Properties) verify() error {
+ if p == nil {
+ return errors.New("lzma: properties are nil")
+ }
+ if !(minLC <= p.LC && p.LC <= maxLC) {
+ return errors.New("lzma: lc out of range")
+ }
+ if !(minLP <= p.LP && p.LP <= maxLP) {
+ return errors.New("lzma: lp out of range")
+ }
+ if !(minPB <= p.PB && p.PB <= maxPB) {
+ return errors.New("lzma: pb out of range")
+ }
+ return nil
+}
+
+// Code converts the properties to a byte. The function assumes that
+// the properties components are all in range.
+func (p Properties) Code() byte {
+ return byte((p.PB*5+p.LP)*9 + p.LC)
+}