/*

* Copyright (C) 2018 The dad-go Authors

* This file is part of The dad-go library.

*

* The dad-go is free software: you can redistribute it and/or modify

* it under the terms of the GNU Lesser General Public License as published by

* the Free Software Foundation, either version 3 of the License, or

* (at your option) any later version.

*

* The dad-go is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU Lesser General Public License for more details.

*

* You should have received a copy of the GNU Lesser General Public License

* along with The dad-go. If not, see <http://www.gnu.org/licenses/>.

*/

package errors

import (

"bytes"

"fmt"

"runtime"

)

type CallStacker interface {

GetCallStack() *CallStack

}

type CallStack struct {

Stacks []uintptr

}

func GetCallStacks(err error) *CallStack {

if err, ok := err.(CallStacker); ok {

return err.GetCallStack()

}

return nil

}

func CallStacksString(call *CallStack) string {

buf := bytes.Buffer{}

if call == nil {

return fmt.Sprintf("No call stack available")

}

for _, stack := range call.Stacks {

f := runtime.FuncForPC(stack)

file, line := f.FileLine(stack)

buf.WriteString(fmt.Sprintf("%s:%d - %s\n", file, line, f.Name()))

}

return fmt.Sprintf("%s", buf.Bytes())

}

func getCallStack(skip int, depth int) *CallStack {

stacks := make([]uintptr, depth)

stacklen := runtime.Callers(skip, stacks)

return &CallStack{

Stacks: stacks[:stacklen],

}

}