tailscale/syncs/locked.go
Josh Bleecher Snyder 997b19545b syncs: use TryLock and TryRLock instead of unsafe
The docs say:

Note that while correct uses of TryLock do exist, they are rare,
and use of TryLock is often a sign of a deeper problem in a particular use of mutexes.

Rare code! Or bad code! Who can tell!

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2022-03-17 10:57:41 -07:00

34 lines
698 B
Go

// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package syncs
import (
"sync"
)
// AssertLocked panics if m is not locked.
func AssertLocked(m *sync.Mutex) {
if m.TryLock() {
m.Unlock()
panic("mutex is not locked")
}
}
// AssertRLocked panics if rw is not locked for reading or writing.
func AssertRLocked(rw *sync.RWMutex) {
if rw.TryLock() {
rw.Unlock()
panic("mutex is not locked")
}
}
// AssertWLocked panics if rw is not locked for writing.
func AssertWLocked(rw *sync.RWMutex) {
if rw.TryRLock() {
rw.RUnlock()
panic("mutex is not rlocked")
}
}