skia2/include/private/SkMutex.h
John Stiles 3b0c30e93c Assert in ~SkMutex that the mutex is unowned.
Destroying a mutex while it is held is never valid, and can be extremely
hard to debug.

Change-Id: I42ff79de7892006337f204621ff59bf84112dcd7
Bug: skia:12943
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/507998
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
2022-02-14 15:23:12 +00:00

65 lines
1.6 KiB
C++

/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkMutex_DEFINED
#define SkMutex_DEFINED
#include "include/core/SkTypes.h"
#include "include/private/SkMacros.h"
#include "include/private/SkSemaphore.h"
#include "include/private/SkThreadAnnotations.h"
#include "include/private/SkThreadID.h"
class SK_CAPABILITY("mutex") SkMutex {
public:
constexpr SkMutex() = default;
~SkMutex() {
this->assertNotHeld();
}
void acquire() SK_ACQUIRE() {
fSemaphore.wait();
SkDEBUGCODE(fOwner = SkGetThreadID();)
}
void release() SK_RELEASE_CAPABILITY() {
this->assertHeld();
SkDEBUGCODE(fOwner = kIllegalThreadID;)
fSemaphore.signal();
}
void assertHeld() SK_ASSERT_CAPABILITY(this) {
SkASSERT(fOwner == SkGetThreadID());
}
void assertNotHeld() {
SkASSERT(fOwner == kIllegalThreadID);
}
private:
SkSemaphore fSemaphore{1};
SkDEBUGCODE(SkThreadID fOwner{kIllegalThreadID};)
};
class SK_SCOPED_CAPABILITY SkAutoMutexExclusive {
public:
SkAutoMutexExclusive(SkMutex& mutex) SK_ACQUIRE(mutex) : fMutex(mutex) { fMutex.acquire(); }
~SkAutoMutexExclusive() SK_RELEASE_CAPABILITY() { fMutex.release(); }
SkAutoMutexExclusive(const SkAutoMutexExclusive&) = delete;
SkAutoMutexExclusive(SkAutoMutexExclusive&&) = delete;
SkAutoMutexExclusive& operator=(const SkAutoMutexExclusive&) = delete;
SkAutoMutexExclusive& operator=(SkAutoMutexExclusive&&) = delete;
private:
SkMutex& fMutex;
};
#endif // SkMutex_DEFINED