Go语言运行时内省：获取调用方包名与函数信息

package main

import (
    "fmt"
    "path/filepath"
    "runtime"
    "strings"
)

// getCallerInfo 获取调用方的详细信息
func getCallerInfo(skip int) (packageName, funcName, filePath string, line int, ok bool) {
    pc, file, line, ok := runtime.Caller(skip + 1) // +1 是为了跳过 getCallerInfo 自身
    if !ok {
        return
    }

    f := runtime.FuncForPC(pc)
    if f == nil {
        return
    }

    fullFuncName := f.Name()
    // 从完整的函数名中解析出包名和函数名
    // 例如：github.com/user/project/pkg.MyFunc
    lastSlash := strings.LastIndex(fullFuncName, "/")
    if lastSlash == -1 {
        // 如果没有斜杠，可能是标准库函数或main包函数
        dotIndex := strings.LastIndex(fullFuncName, ".")
        if dotIndex != -1 {
            packageName = fullFuncName[:dotIndex]
            funcName = fullFuncName[dotIndex+1:]
        } else {
            // 无法解析，可能直接是函数名
            funcName = fullFuncName
        }
    } else {
        // 有斜杠，尝试解析包路径和函数名
        pkgAndFunc := fullFuncName[lastSlash+1:] // pkg.MyFunc
        dotIndex := strings.LastIndex(pkgAndFunc, ".")
        if dotIndex != -1 {
            packageName = pkgAndFunc[:dotIndex] // pkg
            funcName = pkgAndFunc[dotIndex+1:]  // MyFunc
            // 更完整的包路径可以从 fullFuncName[:lastSlash] 结合 packageName 获得
            // 但这里我们主要关注最终的包名
        } else {
            // 无法解析，可能直接是函数名
            funcName = pkgAndFunc
        }
    }

    // 进一步优化，从完整函数名中提取出完整的包路径
    // 例如 "github.com/mattn/go-gtk/gtk.Init" -> "github.com/mattn/go-gtk/gtk"
    if dotIndex := strings.LastIndex(fullFuncName, "."); dotIndex != -1 {
        potentialPackagePath := fullFuncName[:dotIndex]
        // 检查这个路径是否是真正的包路径
        // 简单的判断方式是它不包含函数名特征
        if !strings.ContainsRune(potentialPackagePath, '/') && !strings.ContainsRune(potentialPackagePath, '.') {
            // 可能是像 "main.main" 这样的情况，packageName 已经处理了
        } else {
            packageName = potentialPackagePath
        }
    }


    return packageName, funcName, file, line, true
}

// 模拟一个库函数
func myLibraryFunction() {
    pkgName, funcName, file, line, ok := getCallerInfo(0)
    if ok {
        fmt.Printf("Library Function Called By:\n")
        fmt.Printf("  Package Path: %s\n", pkgName)
        fmt.Printf("  Function Name: %s\n", funcName)
        fmt.Printf("  File: %s\n", filepath.Base(file)) // 只显示文件名
        fmt.Printf("  Line: %d\n", line)
    } else {
        fmt.Println("Failed to get caller info.")
    }
    fmt.Println("---")
}

// 另一个函数，用于从 main 包调用库函数
func callerInMainPackage() {
    myLibraryFunction()
}

func main() {
    fmt.Println("Calling from main.main directly:")
    myLibraryFunction()

    fmt.Println("Calling from another function in main package:")
    callerInMainPackage()

    fmt.Println("Calling from an anonymous function:")
    func() {
        myLibraryFunction()
    }()
}

Calling from main.main directly:
Library Function Called By:
  Package Path: main
  Function Name: main
  File: main.go
  Line: 83
---
Calling from another function in main package:
Library Function Called By:
  Package Path: main
  Function Name: callerInMainPackage
  File: main.go
  Line: 78
---
Calling from an anonymous function:
Library Function Called By:
  Package Path: main
  Function Name: main.func1
  File: main.go
  Line: 87
---