40 lines
1 KiB
Go
40 lines
1 KiB
Go
// Copyright (c) HashiCorp, Inc.
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// SPDX-License-Identifier: MPL-2.0
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/*
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Package mutex implements the sync.Locker interface using x/sync/semaphore. It
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may be used as a replacement for sync.Mutex when one or more goroutines need to
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allow their calls to Lock to be cancelled by context cancellation.
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*/
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package mutex
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import (
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"context"
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"golang.org/x/sync/semaphore"
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)
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type Mutex semaphore.Weighted
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// New returns a Mutex that is ready for use.
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func New() *Mutex {
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return (*Mutex)(semaphore.NewWeighted(1))
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}
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func (m *Mutex) Lock() {
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_ = (*semaphore.Weighted)(m).Acquire(context.Background(), 1)
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}
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func (m *Mutex) Unlock() {
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(*semaphore.Weighted)(m).Release(1)
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}
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// TryLock acquires the mutex, blocking until resources are available or ctx is
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// done. On success, returns nil. On failure, returns ctx.Err() and leaves the
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// semaphore unchanged.
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//
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// If ctx is already done, Acquire may still succeed without blocking.
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func (m *Mutex) TryLock(ctx context.Context) error {
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return (*semaphore.Weighted)(m).Acquire(ctx, 1)
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}
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