/*

 * Copyright 2016 Google Inc.

 *

 * Use of this source code is governed by a BSD-style license that can be

 * found in the LICENSE file.

 */

#ifndef skgpu_SingleOwner_DEFINED

#define skgpu_SingleOwner_DEFINED

#include "include/private/base/SkDebug.h" // IWYU pragma: keep

#if defined(SK_DEBUG)

#include "include/private/base/SkAssert.h"

#include "include/private/base/SkMutex.h"

#include "include/private/base/SkThreadAnnotations.h"

#include "include/private/base/SkThreadID.h"

#endif

namespace skgpu {

#if defined(SK_DEBUG)

#define SKGPU_ASSERT_SINGLE_OWNER(obj) \

    skgpu::SingleOwner::AutoEnforce debug_SingleOwner(obj, __FILE__, __LINE__);

// This is a debug tool to verify an object is only being used from one thread at a time.

class SingleOwner {

public:

     SingleOwner() : fOwner(kIllegalThreadID), fReentranceCount(0) {}

     struct AutoEnforce {

         AutoEnforce(SingleOwner* so, const char* file, int line)

                : fFile(file), fLine(line), fSO(so) {

             fSO->enter(file, line);

         }

         ~AutoEnforce() { fSO->exit(fFile, fLine); }

         const char* fFile;

         int fLine;

         SingleOwner* fSO;

     };

private:

     void enter(const char* file, int line) {

         SkAutoMutexExclusive lock(fMutex);

         SkThreadID self = SkGetThreadID();

         SkASSERTF(fOwner == self || fOwner == kIllegalThreadID, "%s:%d Single owner failure.",

                   file, line);

         fReentranceCount++;

         fOwner = self;

     }

     void exit(const char* file, int line) {

         SkAutoMutexExclusive lock(fMutex);

         SkASSERTF(fOwner == SkGetThreadID(), "%s:%d Single owner failure.", file, line);

         fReentranceCount--;

         if (fReentranceCount == 0) {

             fOwner = kIllegalThreadID;

         }

     }

     SkMutex fMutex;

     SkThreadID fOwner    SK_GUARDED_BY(fMutex);

     int fReentranceCount SK_GUARDED_BY(fMutex);

};

#else

#define SKGPU_ASSERT_SINGLE_OWNER(obj)

class SingleOwner {}; // Provide a no-op implementation so we can pass pointers to constructors

#endif

} // namespace skgpu

#endif