From 6bf0a5cb5034a7e684dcc3500e841785237ce2dd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 19:32:43 +0200 Subject: Adding upstream version 1:115.7.0. Signed-off-by: Daniel Baumann --- xpcom/threads/RecursiveMutex.h | 120 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) create mode 100644 xpcom/threads/RecursiveMutex.h (limited to 'xpcom/threads/RecursiveMutex.h') diff --git a/xpcom/threads/RecursiveMutex.h b/xpcom/threads/RecursiveMutex.h new file mode 100644 index 0000000000..dde21c9a35 --- /dev/null +++ b/xpcom/threads/RecursiveMutex.h @@ -0,0 +1,120 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +// A lock that can be acquired multiple times on the same thread. + +#ifndef mozilla_RecursiveMutex_h +#define mozilla_RecursiveMutex_h + +#include "mozilla/ThreadSafety.h" +#include "mozilla/BlockingResourceBase.h" + +#ifndef XP_WIN +# include +#endif + +namespace mozilla { + +class MOZ_CAPABILITY("recursive mutex") RecursiveMutex + : public BlockingResourceBase { + public: + explicit RecursiveMutex(const char* aName); + ~RecursiveMutex(); + +#ifdef DEBUG + void Lock() MOZ_CAPABILITY_ACQUIRE(); + void Unlock() MOZ_CAPABILITY_RELEASE(); +#else + void Lock() MOZ_CAPABILITY_ACQUIRE() { LockInternal(); } + void Unlock() MOZ_CAPABILITY_RELEASE() { UnlockInternal(); } +#endif + +#ifdef DEBUG + /** + * AssertCurrentThreadIn + **/ + void AssertCurrentThreadIn() const MOZ_ASSERT_CAPABILITY(this); + /** + * AssertNotCurrentThreadIn + **/ + void AssertNotCurrentThreadIn() const MOZ_EXCLUDES(this) { + // Not currently implemented. See bug 476536 for discussion. + } +#else + void AssertCurrentThreadIn() const MOZ_ASSERT_CAPABILITY(this) {} + void AssertNotCurrentThreadIn() const MOZ_EXCLUDES(this) {} +#endif + + private: + RecursiveMutex() = delete; + RecursiveMutex(const RecursiveMutex&) = delete; + RecursiveMutex& operator=(const RecursiveMutex&) = delete; + + void LockInternal(); + void UnlockInternal(); + +#ifdef DEBUG + PRThread* mOwningThread; + size_t mEntryCount; +#endif + +#if !defined(XP_WIN) + pthread_mutex_t mMutex; +#else + // We eschew including windows.h and using CRITICAL_SECTION here so that files + // including us don't also pull in windows.h. Just use a type that's big + // enough for CRITICAL_SECTION, and we'll fix it up later. + void* mMutex[6]; +#endif +}; + +class MOZ_RAII MOZ_SCOPED_CAPABILITY RecursiveMutexAutoLock { + public: + explicit RecursiveMutexAutoLock(RecursiveMutex& aRecursiveMutex) + MOZ_CAPABILITY_ACQUIRE(aRecursiveMutex) + : mRecursiveMutex(&aRecursiveMutex) { + NS_ASSERTION(mRecursiveMutex, "null mutex"); + mRecursiveMutex->Lock(); + } + + ~RecursiveMutexAutoLock(void) MOZ_CAPABILITY_RELEASE() { + mRecursiveMutex->Unlock(); + } + + private: + RecursiveMutexAutoLock() = delete; + RecursiveMutexAutoLock(const RecursiveMutexAutoLock&) = delete; + RecursiveMutexAutoLock& operator=(const RecursiveMutexAutoLock&) = delete; + static void* operator new(size_t) noexcept(true); + + mozilla::RecursiveMutex* mRecursiveMutex; +}; + +class MOZ_RAII MOZ_SCOPED_CAPABILITY RecursiveMutexAutoUnlock { + public: + explicit RecursiveMutexAutoUnlock(RecursiveMutex& aRecursiveMutex) + MOZ_SCOPED_UNLOCK_RELEASE(aRecursiveMutex) + : mRecursiveMutex(&aRecursiveMutex) { + NS_ASSERTION(mRecursiveMutex, "null mutex"); + mRecursiveMutex->Unlock(); + } + + ~RecursiveMutexAutoUnlock(void) MOZ_SCOPED_UNLOCK_REACQUIRE() { + mRecursiveMutex->Lock(); + } + + private: + RecursiveMutexAutoUnlock() = delete; + RecursiveMutexAutoUnlock(const RecursiveMutexAutoUnlock&) = delete; + RecursiveMutexAutoUnlock& operator=(const RecursiveMutexAutoUnlock&) = delete; + static void* operator new(size_t) noexcept(true); + + mozilla::RecursiveMutex* mRecursiveMutex; +}; + +} // namespace mozilla + +#endif // mozilla_RecursiveMutex_h -- cgit v1.2.3