GoToSocial/internal/gtserror/new_caller.go

93 lines
2.2 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//go:build !noerrcaller
package gtserror
import (
"errors"
"fmt"
"runtime"
"strings"
)
// Caller returns whether created errors will prepend calling function name.
const Caller = true
// cerror wraps an error with a string
// prefix of the caller function name.
type cerror struct {
c string
e error
}
func (ce *cerror) Error() string {
msg := ce.e.Error()
return ce.c + ": " + msg
}
func (ce *cerror) Unwrap() error {
return ce.e
}
// newAt is the same as New() but allows specifying calldepth.
func newAt(calldepth int, msg string) error {
return &cerror{
c: caller(calldepth + 1),
e: errors.New(msg),
}
}
// newfAt is the same as Newf() but allows specifying calldepth.
func newfAt(calldepth int, msgf string, args ...any) error {
return &cerror{
c: caller(calldepth + 1),
e: fmt.Errorf(msgf, args...),
}
}
// caller fetches the calling function name, skipping 'depth'. Results are cached per PC.
func caller(depth int) string {
var pcs [1]uintptr
// Fetch calling function using calldepth
_ = runtime.Callers(depth, pcs[:])
fn := runtime.FuncForPC(pcs[0])
if fn == nil {
return ""
}
// Get func name.
name := fn.Name()
// Drop everything but but function name itself
if idx := strings.LastIndexByte(name, '.'); idx >= 0 {
name = name[idx+1:]
}
const params = `[...]`
// Drop any generic type parameter markers
if idx := strings.Index(name, params); idx >= 0 {
name = name[:idx] + name[idx+len(params):]
}
return name
}