distribution/vendor/github.com/bugsnag/bugsnag-go/errors/error.go
Olivier Gambier 77e69b9cf3 Move to vendor
Signed-off-by: Olivier Gambier <olivier@docker.com>
2016-03-22 10:45:49 -07:00

90 lines
2.1 KiB
Go

// Package errors provides errors that have stack-traces.
package errors
import (
"bytes"
"fmt"
"reflect"
"runtime"
)
// The maximum number of stackframes on any error.
var MaxStackDepth = 50
// Error is an error with an attached stacktrace. It can be used
// wherever the builtin error interface is expected.
type Error struct {
Err error
stack []uintptr
frames []StackFrame
}
// New makes an Error from the given value. If that value is already an
// error then it will be used directly, if not, it will be passed to
// fmt.Errorf("%v"). The skip parameter indicates how far up the stack
// to start the stacktrace. 0 is from the current call, 1 from its caller, etc.
func New(e interface{}, skip int) *Error {
var err error
switch e := e.(type) {
case *Error:
return e
case error:
err = e
default:
err = fmt.Errorf("%v", e)
}
stack := make([]uintptr, MaxStackDepth)
length := runtime.Callers(2+skip, stack[:])
return &Error{
Err: err,
stack: stack[:length],
}
}
// Errorf creates a new error with the given message. You can use it
// as a drop-in replacement for fmt.Errorf() to provide descriptive
// errors in return values.
func Errorf(format string, a ...interface{}) *Error {
return New(fmt.Errorf(format, a...), 1)
}
// Error returns the underlying error's message.
func (err *Error) Error() string {
return err.Err.Error()
}
// Stack returns the callstack formatted the same way that go does
// in runtime/debug.Stack()
func (err *Error) Stack() []byte {
buf := bytes.Buffer{}
for _, frame := range err.StackFrames() {
buf.WriteString(frame.String())
}
return buf.Bytes()
}
// StackFrames returns an array of frames containing information about the
// stack.
func (err *Error) StackFrames() []StackFrame {
if err.frames == nil {
err.frames = make([]StackFrame, len(err.stack))
for i, pc := range err.stack {
err.frames[i] = NewStackFrame(pc)
}
}
return err.frames
}
// TypeName returns the type this error. e.g. *errors.stringError.
func (err *Error) TypeName() string {
if _, ok := err.Err.(uncaughtPanic); ok {
return "panic"
}
return reflect.TypeOf(err.Err).String()
}