Golang: Stack Trace on Panic

stacktrace.go

func stackDump(err *error, f interface{}) {
	fname := runtime.FuncForPC(reflect.ValueOf(f).Pointer()).Name()
	_, file, line, _ := runtime.Caller(4) // this skips the first 4 that are called under log.Panic()
	if r := recover(); r != nil {
		fmt.Printf("%s (recover): %v\n", fname, r)
		if err != nil {
			*err = fmt.Errorf("%v", r)
		}
	} else if err != nil && *err != nil {
		fmt.Printf("%s : %v\n", fname, *err)
	}

	buf := make([]byte, 1<<10)
	runtime.Stack(buf, false)
	fmt.Println("==> stack trace: [PANIC:", file, line, fname+"]")
	fmt.Println(string(buf))
}

usage.go

package main

import (
	"fmt"
	"log"
	"os"
	"reflect"
	"runtime"
	"strings"
)

// define func stackDump(err *error, f interface{})

func foo() (err error) {
	defer stackDump(&err, foo)

	_, err = os.Open("no_such_file.exists")
	if err != nil {
		log.Panic(err)
	}

	return err
}

func main() {
	foo()
}