GoToSocial/internal/util/fns.go

69 lines
1.7 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/>.
package util
import (
"fmt"
"os"
"runtime"
"codeberg.org/gruf/go-errors/v2"
)
// Must executes 'fn' repeatedly until
// it successfully returns without panic.
func Must(fn func()) {
if fn == nil {
panic("nil func")
}
for !func() (done bool) {
defer func() {
if r := recover(); r != nil {
// Gather calling func frames.
pcs := make([]uintptr, 10)
n := runtime.Callers(3, pcs)
i := runtime.CallersFrames(pcs[:n])
c := gatherFrames(i, n)
const msg = "recovered panic: %v\n\n%s\n"
fmt.Fprintf(os.Stderr, msg, r, c.String())
}
}()
fn()
done = true
return
}() { //nolint
}
}
// gatherFrames collates runtime frames from a frame iterator.
func gatherFrames(iter *runtime.Frames, n int) errors.Callers {
if iter == nil {
return nil
}
frames := make([]runtime.Frame, 0, n)
for {
f, ok := iter.Next()
if !ok {
break
}
frames = append(frames, f)
}
return frames
}