1// Copyright 2015 Google Inc. All rights reserved 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15package kati 16 17import "sync" 18 19type symtabT struct { 20 mu sync.Mutex 21 m map[string]string 22} 23 24var symtab = &symtabT{ 25 m: make(map[string]string), 26} 27 28func intern(s string) string { 29 symtab.mu.Lock() 30 v, ok := symtab.m[s] 31 if ok { 32 symtab.mu.Unlock() 33 return v 34 } 35 symtab.m[s] = s 36 symtab.mu.Unlock() 37 return s 38} 39 40func internBytes(s []byte) string { 41 return intern(string(s)) 42} 43