github.com/go-spring/spring-base@v1.1.3/log/internal/caller.go (about) 1 /* 2 * Copyright 2012-2019 the original author or authors. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * https://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package internal 18 19 import ( 20 "runtime" 21 "sync" 22 ) 23 24 // frameMap 用于缓存调用点,基准测试表明使用缓存大约有 50% 的性能提升。 25 var frameMap sync.Map 26 27 // Caller 获取调用点的文件及行号信息,fast 为 true 时使用缓存进行加速。 28 func Caller(skip int, fast bool) (file string, line int, loaded bool) { 29 30 if !fast { 31 _, file, line, loaded = runtime.Caller(skip + 1) 32 return 33 } 34 35 rpc := make([]uintptr, 1) 36 n := runtime.Callers(skip+2, rpc[:]) 37 if n < 1 { 38 return 39 } 40 pc := rpc[0] 41 if v, ok := frameMap.Load(pc); ok { 42 e := v.(*runtime.Frame) 43 return e.File, e.Line, true 44 } 45 frame, _ := runtime.CallersFrames(rpc).Next() 46 frameMap.Store(pc, &frame) 47 return frame.File, frame.Line, false 48 }