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 15 package kati 16 17 import "sync" 18 19 type symtabT struct { 20 mu sync.Mutex 21 m map[string]string 22 } 23 24 var symtab = &symtabT{ 25 m: make(map[string]string), 26 } 27 28 func 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 40 func internBytes(s []byte) string { 41 return intern(string(s)) 42 } 43
