serve grpc and http on the same socket

Signed-off-by: Antonio Murdaca <runcom@redhat.com>

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)
+}