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-rw-r--r--vendor/github.com/soheilhy/cmux/patricia.go179
1 files changed, 179 insertions, 0 deletions
diff --git a/vendor/github.com/soheilhy/cmux/patricia.go b/vendor/github.com/soheilhy/cmux/patricia.go
new file mode 100644
index 0000000..c3e3d85
--- /dev/null
+++ b/vendor/github.com/soheilhy/cmux/patricia.go
@@ -0,0 +1,179 @@
+// Copyright 2016 The CMux Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied. See the License for the specific language governing
+// permissions and limitations under the License.
+
+package cmux
+
+import (
+ "bytes"
+ "io"
+)
+
+// patriciaTree is a simple patricia tree that handles []byte instead of string
+// and cannot be changed after instantiation.
+type patriciaTree struct {
+ root *ptNode
+ maxDepth int // max depth of the tree.
+}
+
+func newPatriciaTree(bs ...[]byte) *patriciaTree {
+ max := 0
+ for _, b := range bs {
+ if max < len(b) {
+ max = len(b)
+ }
+ }
+ return &patriciaTree{
+ root: newNode(bs),
+ maxDepth: max + 1,
+ }
+}
+
+func newPatriciaTreeString(strs ...string) *patriciaTree {
+ b := make([][]byte, len(strs))
+ for i, s := range strs {
+ b[i] = []byte(s)
+ }
+ return newPatriciaTree(b...)
+}
+
+func (t *patriciaTree) matchPrefix(r io.Reader) bool {
+ buf := make([]byte, t.maxDepth)
+ n, _ := io.ReadFull(r, buf)
+ return t.root.match(buf[:n], true)
+}
+
+func (t *patriciaTree) match(r io.Reader) bool {
+ buf := make([]byte, t.maxDepth)
+ n, _ := io.ReadFull(r, buf)
+ return t.root.match(buf[:n], false)
+}
+
+type ptNode struct {
+ prefix []byte
+ next map[byte]*ptNode
+ terminal bool
+}
+
+func newNode(strs [][]byte) *ptNode {
+ if len(strs) == 0 {
+ return &ptNode{
+ prefix: []byte{},
+ terminal: true,
+ }
+ }
+
+ if len(strs) == 1 {
+ return &ptNode{
+ prefix: strs[0],
+ terminal: true,
+ }
+ }
+
+ p, strs := splitPrefix(strs)
+ n := &ptNode{
+ prefix: p,
+ }
+
+ nexts := make(map[byte][][]byte)
+ for _, s := range strs {
+ if len(s) == 0 {
+ n.terminal = true
+ continue
+ }
+ nexts[s[0]] = append(nexts[s[0]], s[1:])
+ }
+
+ n.next = make(map[byte]*ptNode)
+ for first, rests := range nexts {
+ n.next[first] = newNode(rests)
+ }
+
+ return n
+}
+
+func splitPrefix(bss [][]byte) (prefix []byte, rest [][]byte) {
+ if len(bss) == 0 || len(bss[0]) == 0 {
+ return prefix, bss
+ }
+
+ if len(bss) == 1 {
+ return bss[0], [][]byte{{}}
+ }
+
+ for i := 0; ; i++ {
+ var cur byte
+ eq := true
+ for j, b := range bss {
+ if len(b) <= i {
+ eq = false
+ break
+ }
+
+ if j == 0 {
+ cur = b[i]
+ continue
+ }
+
+ if cur != b[i] {
+ eq = false
+ break
+ }
+ }
+
+ if !eq {
+ break
+ }
+
+ prefix = append(prefix, cur)
+ }
+
+ rest = make([][]byte, 0, len(bss))
+ for _, b := range bss {
+ rest = append(rest, b[len(prefix):])
+ }
+
+ return prefix, rest
+}
+
+func (n *ptNode) match(b []byte, prefix bool) bool {
+ l := len(n.prefix)
+ if l > 0 {
+ if l > len(b) {
+ l = len(b)
+ }
+ if !bytes.Equal(b[:l], n.prefix) {
+ return false
+ }
+ }
+
+ if n.terminal && (prefix || len(n.prefix) == len(b)) {
+ return true
+ }
+
+ if l >= len(b) {
+ return false
+ }
+
+ nextN, ok := n.next[b[l]]
+ if !ok {
+ return false
+ }
+
+ if l == len(b) {
+ b = b[l:l]
+ } else {
+ b = b[l+1:]
+ }
+ return nextN.match(b, prefix)
+}