mirror of
https://github.com/netbirdio/gvisor.git
synced 2026-05-22 17:12:49 -07:00
Michael Pratt
65569cfca0
None of the dependencies have changed in 1.15. It may be possible to simplify some of the wrappers in rawfile following 1.13, but that can come in a later change. PiperOrigin-RevId: 313863264
50 lines
936 B
Go
50 lines
936 B
Go
// Copyright 2019 The gVisor Authors.
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//
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// +build go1.13
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// +build !go1.16
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// When updating the build constraint (above), check that syncMutex matches the
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// standard library sync.Mutex definition.
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package sync
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import (
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"sync"
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"sync/atomic"
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"unsafe"
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)
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// Mutex is a try lock.
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type Mutex struct {
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sync.Mutex
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}
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type syncMutex struct {
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state int32
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sema uint32
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}
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func (m *Mutex) state() *int32 {
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return &(*syncMutex)(unsafe.Pointer(&m.Mutex)).state
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}
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const (
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mutexUnlocked = 0
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mutexLocked = 1
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)
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// TryLock tries to aquire the mutex. It returns true if it succeeds and false
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// otherwise. TryLock does not block.
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func (m *Mutex) TryLock() bool {
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if atomic.CompareAndSwapInt32(m.state(), mutexUnlocked, mutexLocked) {
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if RaceEnabled {
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RaceAcquire(unsafe.Pointer(&m.Mutex))
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}
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return true
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}
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return false
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}
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