gecko/xpcom/glue/nsThreadUtils.h
Cervantes Yu 33b1e54f81 Backed out 2 changesets (bug 1138620)
Backed out changeset e60b4b01c05d (bug 1138620)
Backed out changeset 52d49dd25d6d (bug 1138620)
2015-04-24 15:05:44 +08:00

1022 lines
32 KiB
C++

/* -*- 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/. */
#ifndef nsThreadUtils_h__
#define nsThreadUtils_h__
#include "prthread.h"
#include "prinrval.h"
#include "MainThreadUtils.h"
#include "nsIThreadManager.h"
#include "nsIThread.h"
#include "nsIRunnable.h"
#include "nsICancelableRunnable.h"
#include "nsStringGlue.h"
#include "nsCOMPtr.h"
#include "nsAutoPtr.h"
#include "mozilla/Atomics.h"
#include "mozilla/Likely.h"
#include "mozilla/TypeTraits.h"
//-----------------------------------------------------------------------------
// These methods are alternatives to the methods on nsIThreadManager, provided
// for convenience.
/**
* Set name of the target thread. This operation is asynchronous.
*/
extern void NS_SetThreadName(nsIThread* aThread, const nsACString& aName);
/**
* Static length version of the above function checking length of the
* name at compile time.
*/
template<size_t LEN>
inline void
NS_SetThreadName(nsIThread* aThread, const char (&aName)[LEN])
{
static_assert(LEN <= 16,
"Thread name must be no more than 16 characters");
NS_SetThreadName(aThread, nsDependentCString(aName));
}
/**
* Create a new thread, and optionally provide an initial event for the thread.
*
* @param aResult
* The resulting nsIThread object.
* @param aInitialEvent
* The initial event to run on this thread. This parameter may be null.
* @param aStackSize
* The size in bytes to reserve for the thread's stack.
*
* @returns NS_ERROR_INVALID_ARG
* Indicates that the given name is not unique.
*/
extern NS_METHOD
NS_NewThread(nsIThread** aResult,
nsIRunnable* aInitialEvent = nullptr,
uint32_t aStackSize = nsIThreadManager::DEFAULT_STACK_SIZE);
/**
* Creates a named thread, otherwise the same as NS_NewThread
*/
template<size_t LEN>
inline NS_METHOD
NS_NewNamedThread(const char (&aName)[LEN],
nsIThread** aResult,
nsIRunnable* aInitialEvent = nullptr,
uint32_t aStackSize = nsIThreadManager::DEFAULT_STACK_SIZE)
{
// Hold a ref while dispatching the initial event to match NS_NewThread()
nsCOMPtr<nsIThread> thread;
nsresult rv = NS_NewThread(getter_AddRefs(thread), nullptr, aStackSize);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
NS_SetThreadName<LEN>(thread, aName);
if (aInitialEvent) {
rv = thread->Dispatch(aInitialEvent, NS_DISPATCH_NORMAL);
NS_WARN_IF_FALSE(NS_SUCCEEDED(rv), "Initial event dispatch failed");
}
*aResult = nullptr;
thread.swap(*aResult);
return rv;
}
/**
* Get a reference to the current thread.
*
* @param aResult
* The resulting nsIThread object.
*/
extern NS_METHOD NS_GetCurrentThread(nsIThread** aResult);
/**
* Dispatch the given event to the current thread.
*
* @param aEvent
* The event to dispatch.
*
* @returns NS_ERROR_INVALID_ARG
* If event is null.
*/
extern NS_METHOD NS_DispatchToCurrentThread(nsIRunnable* aEvent);
/**
* Dispatch the given event to the main thread.
*
* @param aEvent
* The event to dispatch.
* @param aDispatchFlags
* The flags to pass to the main thread's dispatch method.
*
* @returns NS_ERROR_INVALID_ARG
* If event is null.
*/
extern NS_METHOD
NS_DispatchToMainThread(nsIRunnable* aEvent,
uint32_t aDispatchFlags = NS_DISPATCH_NORMAL);
#ifndef XPCOM_GLUE_AVOID_NSPR
/**
* Process all pending events for the given thread before returning. This
* method simply calls ProcessNextEvent on the thread while HasPendingEvents
* continues to return true and the time spent in NS_ProcessPendingEvents
* does not exceed the given timeout value.
*
* @param aThread
* The thread object for which to process pending events. If null, then
* events will be processed for the current thread.
* @param aTimeout
* The maximum number of milliseconds to spend processing pending events.
* Events are not pre-empted to honor this timeout. Rather, the timeout
* value is simply used to determine whether or not to process another event.
* Pass PR_INTERVAL_NO_TIMEOUT to specify no timeout.
*/
extern NS_METHOD
NS_ProcessPendingEvents(nsIThread* aThread,
PRIntervalTime aTimeout = PR_INTERVAL_NO_TIMEOUT);
#endif
/**
* Shortcut for nsIThread::HasPendingEvents.
*
* It is an error to call this function when the given thread is not the
* current thread. This function will return false if called from some
* other thread.
*
* @param aThread
* The current thread or null.
*
* @returns
* A boolean value that if "true" indicates that there are pending events
* in the current thread's event queue.
*/
extern bool NS_HasPendingEvents(nsIThread* aThread = nullptr);
/**
* Shortcut for nsIThread::ProcessNextEvent.
*
* It is an error to call this function when the given thread is not the
* current thread. This function will simply return false if called
* from some other thread.
*
* @param aThread
* The current thread or null.
* @param aMayWait
* A boolean parameter that if "true" indicates that the method may block
* the calling thread to wait for a pending event.
*
* @returns
* A boolean value that if "true" indicates that an event from the current
* thread's event queue was processed.
*/
extern bool NS_ProcessNextEvent(nsIThread* aThread = nullptr,
bool aMayWait = true);
//-----------------------------------------------------------------------------
// Helpers that work with nsCOMPtr:
inline already_AddRefed<nsIThread>
do_GetCurrentThread()
{
nsIThread* thread = nullptr;
NS_GetCurrentThread(&thread);
return already_AddRefed<nsIThread>(thread);
}
inline already_AddRefed<nsIThread>
do_GetMainThread()
{
nsIThread* thread = nullptr;
NS_GetMainThread(&thread);
return already_AddRefed<nsIThread>(thread);
}
//-----------------------------------------------------------------------------
#ifdef MOZILLA_INTERNAL_API
// Fast access to the current thread. Do not release the returned pointer! If
// you want to use this pointer from some other thread, then you will need to
// AddRef it. Otherwise, you should only consider this pointer valid from code
// running on the current thread.
extern nsIThread* NS_GetCurrentThread();
#endif
//-----------------------------------------------------------------------------
#ifndef XPCOM_GLUE_AVOID_NSPR
// This class is designed to be subclassed.
class nsRunnable : public nsIRunnable
{
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSIRUNNABLE
nsRunnable() {}
protected:
virtual ~nsRunnable() {}
};
// This class is designed to be subclassed.
class nsCancelableRunnable : public nsICancelableRunnable
{
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSIRUNNABLE
NS_DECL_NSICANCELABLERUNNABLE
nsCancelableRunnable() {}
protected:
virtual ~nsCancelableRunnable() {}
};
// An event that can be used to call a C++11 functions or function objects,
// including lambdas. The function must have no required arguments, and must
// return void.
template<typename Function>
class nsRunnableFunction : public nsRunnable
{
public:
explicit nsRunnableFunction(const Function& aFunction)
: mFunction(aFunction)
{ }
NS_IMETHOD Run() {
static_assert(mozilla::IsVoid<decltype(mFunction())>::value,
"The lambda must return void!");
mFunction();
return NS_OK;
}
private:
Function mFunction;
};
template<typename Function>
nsRunnableFunction<Function>* NS_NewRunnableFunction(const Function& aFunction)
{
return new nsRunnableFunction<Function>(aFunction);
}
// An event that can be used to call a method on a class. The class type must
// support reference counting. This event supports Revoke for use
// with nsRevocableEventPtr.
template<class ClassType,
typename ReturnType = void,
bool Owning = true>
class nsRunnableMethod : public nsRunnable
{
public:
virtual void Revoke() = 0;
// These ReturnTypeEnforcer classes set up a blacklist for return types that
// we know are not safe. The default ReturnTypeEnforcer compiles just fine but
// already_AddRefed will not.
template<typename OtherReturnType>
class ReturnTypeEnforcer
{
public:
typedef int ReturnTypeIsSafe;
};
template<class T>
class ReturnTypeEnforcer<already_AddRefed<T>>
{
// No ReturnTypeIsSafe makes this illegal!
};
// Make sure this return type is safe.
typedef typename ReturnTypeEnforcer<ReturnType>::ReturnTypeIsSafe check;
};
template<class ClassType, bool Owning>
struct nsRunnableMethodReceiver
{
nsRefPtr<ClassType> mObj;
explicit nsRunnableMethodReceiver(ClassType* aObj) : mObj(aObj) {}
~nsRunnableMethodReceiver() { Revoke(); }
ClassType* Get() const { return mObj.get(); }
void Revoke() { mObj = nullptr; }
};
template<class ClassType>
struct nsRunnableMethodReceiver<ClassType, false>
{
ClassType* MOZ_NON_OWNING_REF mObj;
explicit nsRunnableMethodReceiver(ClassType* aObj) : mObj(aObj) {}
ClassType* Get() const { return mObj; }
void Revoke() { mObj = nullptr; }
};
template<typename Method, bool Owning> struct nsRunnableMethodTraits;
template<class C, typename R, bool Owning, typename... As>
struct nsRunnableMethodTraits<R(C::*)(As...), Owning>
{
typedef C class_type;
typedef R return_type;
typedef nsRunnableMethod<C, R, Owning> base_type;
};
#ifdef NS_HAVE_STDCALL
template<class C, typename R, bool Owning, typename... As>
struct nsRunnableMethodTraits<R(__stdcall C::*)(As...), Owning>
{
typedef C class_type;
typedef R return_type;
typedef nsRunnableMethod<C, R, Owning> base_type;
};
template<class C, typename R, bool Owning>
struct nsRunnableMethodTraits<R(NS_STDCALL C::*)(), Owning>
{
typedef C class_type;
typedef R return_type;
typedef nsRunnableMethod<C, R, Owning> base_type;
};
#endif
// IsParameterStorageClass<T>::value is true if T is a parameter-storage class
// that will be recognized by NS_New[NonOwning]RunnableMethodWithArg[s] to
// force a specific storage&passing strategy (instead of inferring one,
// see ParameterStorage).
// When creating a new storage class, add a specialization for it to be
// recognized.
template<typename T>
struct IsParameterStorageClass : public mozilla::FalseType {};
// StoreXPassByY structs used to inform nsRunnableMethodArguments how to
// store arguments, and how to pass them to the target method.
template<typename T>
struct StoreCopyPassByValue
{
typedef T stored_type;
typedef T passed_type;
stored_type m;
template <typename A>
StoreCopyPassByValue(A&& a) : m(mozilla::Forward<A>(a)) {}
passed_type PassAsParameter() { return m; }
};
template<typename S>
struct IsParameterStorageClass<StoreCopyPassByValue<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreCopyPassByConstLRef
{
typedef T stored_type;
typedef const T& passed_type;
stored_type m;
template <typename A>
StoreCopyPassByConstLRef(A&& a) : m(mozilla::Forward<A>(a)) {}
passed_type PassAsParameter() { return m; }
};
template<typename S>
struct IsParameterStorageClass<StoreCopyPassByConstLRef<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreCopyPassByLRef
{
typedef T stored_type;
typedef T& passed_type;
stored_type m;
template <typename A>
StoreCopyPassByLRef(A&& a) : m(mozilla::Forward<A>(a)) {}
passed_type PassAsParameter() { return m; }
};
template<typename S>
struct IsParameterStorageClass<StoreCopyPassByLRef<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreCopyPassByRRef
{
typedef T stored_type;
typedef T&& passed_type;
stored_type m;
template <typename A>
StoreCopyPassByRRef(A&& a) : m(mozilla::Forward<A>(a)) {}
passed_type PassAsParameter() { return mozilla::Move(m); }
};
template<typename S>
struct IsParameterStorageClass<StoreCopyPassByRRef<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreRefPassByLRef
{
typedef T& stored_type;
typedef T& passed_type;
stored_type m;
template <typename A>
StoreRefPassByLRef(A& a) : m(a) {}
passed_type PassAsParameter() { return m; }
};
template<typename S>
struct IsParameterStorageClass<StoreRefPassByLRef<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreConstRefPassByConstLRef
{
typedef const T& stored_type;
typedef const T& passed_type;
stored_type m;
template <typename A>
StoreConstRefPassByConstLRef(const A& a) : m(a) {}
passed_type PassAsParameter() { return m; }
};
template<typename S>
struct IsParameterStorageClass<StoreConstRefPassByConstLRef<S>>
: public mozilla::TrueType {};
template<typename T>
struct StorensRefPtrPassByPtr
{
typedef nsRefPtr<T> stored_type;
typedef T* passed_type;
stored_type m;
template <typename A>
StorensRefPtrPassByPtr(A a) : m(a) {}
passed_type PassAsParameter() { return m.get(); }
};
template<typename S>
struct IsParameterStorageClass<StorensRefPtrPassByPtr<S>>
: public mozilla::TrueType {};
template<typename T>
struct StorePtrPassByPtr
{
typedef T* stored_type;
typedef T* passed_type;
stored_type m;
template <typename A>
StorePtrPassByPtr(A a) : m(a) {}
passed_type PassAsParameter() { return m; }
};
template<typename S>
struct IsParameterStorageClass<StorePtrPassByPtr<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreConstPtrPassByConstPtr
{
typedef const T* stored_type;
typedef const T* passed_type;
stored_type m;
template <typename A>
StoreConstPtrPassByConstPtr(A a) : m(a) {}
passed_type PassAsParameter() { return m; }
};
template<typename S>
struct IsParameterStorageClass<StoreConstPtrPassByConstPtr<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreCopyPassByConstPtr
{
typedef T stored_type;
typedef const T* passed_type;
stored_type m;
template <typename A>
StoreCopyPassByConstPtr(A&& a) : m(mozilla::Forward<A>(a)) {}
passed_type PassAsParameter() { return &m; }
};
template<typename S>
struct IsParameterStorageClass<StoreCopyPassByConstPtr<S>>
: public mozilla::TrueType {};
template<typename T>
struct StoreCopyPassByPtr
{
typedef T stored_type;
typedef T* passed_type;
stored_type m;
template <typename A>
StoreCopyPassByPtr(A&& a) : m(mozilla::Forward<A>(a)) {}
passed_type PassAsParameter() { return &m; }
};
template<typename S>
struct IsParameterStorageClass<StoreCopyPassByPtr<S>>
: public mozilla::TrueType {};
namespace detail {
template<typename TWithoutPointer>
struct NonnsISupportsPointerStorageClass
: mozilla::Conditional<mozilla::IsConst<TWithoutPointer>::value,
StoreConstPtrPassByConstPtr<
typename mozilla::RemoveConst<TWithoutPointer>::Type>,
StorePtrPassByPtr<TWithoutPointer>>
{};
template<typename TWithoutPointer>
struct PointerStorageClass
: mozilla::Conditional<mozilla::IsBaseOf<nsISupports, TWithoutPointer>::value,
StorensRefPtrPassByPtr<TWithoutPointer>,
typename NonnsISupportsPointerStorageClass<
TWithoutPointer
>::Type>
{};
template<typename TWithoutRef>
struct LValueReferenceStorageClass
: mozilla::Conditional<mozilla::IsConst<TWithoutRef>::value,
StoreConstRefPassByConstLRef<
typename mozilla::RemoveConst<TWithoutRef>::Type>,
StoreRefPassByLRef<TWithoutRef>>
{};
template<typename T>
struct NonLValueReferenceStorageClass
: mozilla::Conditional<mozilla::IsRvalueReference<T>::value,
StoreCopyPassByRRef<
typename mozilla::RemoveReference<T>::Type>,
StoreCopyPassByValue<T>>
{};
template<typename T>
struct NonPointerStorageClass
: mozilla::Conditional<mozilla::IsLvalueReference<T>::value,
typename LValueReferenceStorageClass<
typename mozilla::RemoveReference<T>::Type
>::Type,
typename NonLValueReferenceStorageClass<T>::Type>
{};
template<typename T>
struct NonParameterStorageClass
: mozilla::Conditional<mozilla::IsPointer<T>::value,
typename PointerStorageClass<
typename mozilla::RemovePointer<T>::Type
>::Type,
typename NonPointerStorageClass<T>::Type>
{};
// Choose storage&passing strategy based on preferred storage type:
// - If IsParameterStorageClass<T>::value is true, use as-is.
// - nsISupports* -> StorensRefPtrPassByPtr<T> : Store nsRefPtr<T>, pass T*
// - const T* -> StoreConstPtrPassByConstPtr<T> : Store const T*, pass const T*
// - T* -> StorePtrPassByPtr<T> : Store T*, pass T*.
// - const T& -> StoreConstRefPassByConstLRef<T>: Store const T&, pass const T&.
// - T& -> StoreRefPassByLRef<T> : Store T&, pass T&.
// - T&& -> StoreCopyPassByRRef<T> : Store T, pass Move(T).
// - Other T -> StoreCopyPassByValue<T> : Store T, pass T.
// Other available explicit options:
// - StoreCopyPassByConstLRef<T> : Store T, pass const T&.
// - StoreCopyPassByLRef<T> : Store T, pass T& (of copy!)
// - StoreCopyPassByConstPtr<T> : Store T, pass const T*
// - StoreCopyPassByPtr<T> : Store T, pass T* (of copy!)
// Or create your own class with PassAsParameter() method, optional
// clean-up in destructor, and with associated IsParameterStorageClass<>.
template<typename T>
struct ParameterStorage
: mozilla::Conditional<IsParameterStorageClass<T>::value,
T,
typename NonParameterStorageClass<T>::Type>
{};
} /* namespace detail */
// struct used to store arguments and later apply them to a method.
template <typename... Ts> struct nsRunnableMethodArguments;
// Specializations for 0-8 arguments, add more as required.
// TODO Use tuple instead; And/or use lambdas (see bug 1152753)
template <>
struct nsRunnableMethodArguments<>
{
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)();
}
};
template <typename T0>
struct nsRunnableMethodArguments<T0>
{
typename ::detail::ParameterStorage<T0>::Type m0;
template<typename A0>
nsRunnableMethodArguments(A0&& a0)
: m0(mozilla::Forward<A0>(a0))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter());
}
};
template <typename T0, typename T1>
struct nsRunnableMethodArguments<T0, T1>
{
typename ::detail::ParameterStorage<T0>::Type m0;
typename ::detail::ParameterStorage<T1>::Type m1;
template<typename A0, typename A1>
nsRunnableMethodArguments(A0&& a0, A1&& a1)
: m0(mozilla::Forward<A0>(a0))
, m1(mozilla::Forward<A1>(a1))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter(), m1.PassAsParameter());
}
};
template <typename T0, typename T1, typename T2>
struct nsRunnableMethodArguments<T0, T1, T2>
{
typename ::detail::ParameterStorage<T0>::Type m0;
typename ::detail::ParameterStorage<T1>::Type m1;
typename ::detail::ParameterStorage<T2>::Type m2;
template<typename A0, typename A1, typename A2>
nsRunnableMethodArguments(A0&& a0, A1&& a1, A2&& a2)
: m0(mozilla::Forward<A0>(a0))
, m1(mozilla::Forward<A1>(a1))
, m2(mozilla::Forward<A2>(a2))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter(), m1.PassAsParameter(), m2.PassAsParameter());
}
};
template <typename T0, typename T1, typename T2, typename T3>
struct nsRunnableMethodArguments<T0, T1, T2, T3>
{
typename ::detail::ParameterStorage<T0>::Type m0;
typename ::detail::ParameterStorage<T1>::Type m1;
typename ::detail::ParameterStorage<T2>::Type m2;
typename ::detail::ParameterStorage<T3>::Type m3;
template<typename A0, typename A1, typename A2, typename A3>
nsRunnableMethodArguments(A0&& a0, A1&& a1, A2&& a2, A3&& a3)
: m0(mozilla::Forward<A0>(a0))
, m1(mozilla::Forward<A1>(a1))
, m2(mozilla::Forward<A2>(a2))
, m3(mozilla::Forward<A3>(a3))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter(), m1.PassAsParameter(),
m2.PassAsParameter(), m3.PassAsParameter());
}
};
template <typename T0, typename T1, typename T2, typename T3, typename T4>
struct nsRunnableMethodArguments<T0, T1, T2, T3, T4>
{
typename ::detail::ParameterStorage<T0>::Type m0;
typename ::detail::ParameterStorage<T1>::Type m1;
typename ::detail::ParameterStorage<T2>::Type m2;
typename ::detail::ParameterStorage<T3>::Type m3;
typename ::detail::ParameterStorage<T4>::Type m4;
template<typename A0, typename A1, typename A2, typename A3, typename A4>
nsRunnableMethodArguments(A0&& a0, A1&& a1, A2&& a2, A3&& a3, A4&& a4)
: m0(mozilla::Forward<A0>(a0))
, m1(mozilla::Forward<A1>(a1))
, m2(mozilla::Forward<A2>(a2))
, m3(mozilla::Forward<A3>(a3))
, m4(mozilla::Forward<A4>(a4))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter(), m1.PassAsParameter(),
m2.PassAsParameter(), m3.PassAsParameter(),
m4.PassAsParameter());
}
};
template <typename T0, typename T1, typename T2, typename T3, typename T4,
typename T5>
struct nsRunnableMethodArguments<T0, T1, T2, T3, T4, T5>
{
typename ::detail::ParameterStorage<T0>::Type m0;
typename ::detail::ParameterStorage<T1>::Type m1;
typename ::detail::ParameterStorage<T2>::Type m2;
typename ::detail::ParameterStorage<T3>::Type m3;
typename ::detail::ParameterStorage<T4>::Type m4;
typename ::detail::ParameterStorage<T5>::Type m5;
template<typename A0, typename A1, typename A2, typename A3, typename A4,
typename A5>
nsRunnableMethodArguments(A0&& a0, A1&& a1, A2&& a2, A3&& a3, A4&& a4,
A5&& a5)
: m0(mozilla::Forward<A0>(a0))
, m1(mozilla::Forward<A1>(a1))
, m2(mozilla::Forward<A2>(a2))
, m3(mozilla::Forward<A3>(a3))
, m4(mozilla::Forward<A4>(a4))
, m5(mozilla::Forward<A5>(a5))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter(), m1.PassAsParameter(),
m2.PassAsParameter(), m3.PassAsParameter(),
m4.PassAsParameter(), m5.PassAsParameter());
}
};
template <typename T0, typename T1, typename T2, typename T3, typename T4,
typename T5, typename T6>
struct nsRunnableMethodArguments<T0, T1, T2, T3, T4, T5, T6>
{
typename ::detail::ParameterStorage<T0>::Type m0;
typename ::detail::ParameterStorage<T1>::Type m1;
typename ::detail::ParameterStorage<T2>::Type m2;
typename ::detail::ParameterStorage<T3>::Type m3;
typename ::detail::ParameterStorage<T4>::Type m4;
typename ::detail::ParameterStorage<T5>::Type m5;
typename ::detail::ParameterStorage<T6>::Type m6;
template<typename A0, typename A1, typename A2, typename A3, typename A4,
typename A5, typename A6>
nsRunnableMethodArguments(A0&& a0, A1&& a1, A2&& a2, A3&& a3, A4&& a4,
A5&& a5, A6&& a6)
: m0(mozilla::Forward<A0>(a0))
, m1(mozilla::Forward<A1>(a1))
, m2(mozilla::Forward<A2>(a2))
, m3(mozilla::Forward<A3>(a3))
, m4(mozilla::Forward<A4>(a4))
, m5(mozilla::Forward<A5>(a5))
, m6(mozilla::Forward<A6>(a6))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter(), m1.PassAsParameter(),
m2.PassAsParameter(), m3.PassAsParameter(),
m4.PassAsParameter(), m5.PassAsParameter(),
m6.PassAsParameter());
}
};
template <typename T0, typename T1, typename T2, typename T3, typename T4,
typename T5, typename T6, typename T7>
struct nsRunnableMethodArguments<T0, T1, T2, T3, T4, T5, T6, T7>
{
typename ::detail::ParameterStorage<T0>::Type m0;
typename ::detail::ParameterStorage<T1>::Type m1;
typename ::detail::ParameterStorage<T2>::Type m2;
typename ::detail::ParameterStorage<T3>::Type m3;
typename ::detail::ParameterStorage<T4>::Type m4;
typename ::detail::ParameterStorage<T5>::Type m5;
typename ::detail::ParameterStorage<T6>::Type m6;
typename ::detail::ParameterStorage<T7>::Type m7;
template<typename A0, typename A1, typename A2, typename A3, typename A4,
typename A5, typename A6, typename A7>
nsRunnableMethodArguments(A0&& a0, A1&& a1, A2&& a2, A3&& a3, A4&& a4,
A5&& a5, A6&& a6, A7&& a7)
: m0(mozilla::Forward<A0>(a0))
, m1(mozilla::Forward<A1>(a1))
, m2(mozilla::Forward<A2>(a2))
, m3(mozilla::Forward<A3>(a3))
, m4(mozilla::Forward<A4>(a4))
, m5(mozilla::Forward<A5>(a5))
, m6(mozilla::Forward<A6>(a6))
, m7(mozilla::Forward<A7>(a7))
{}
template<class C, typename M> void apply(C* o, M m)
{
((*o).*m)(m0.PassAsParameter(), m1.PassAsParameter(),
m2.PassAsParameter(), m3.PassAsParameter(),
m4.PassAsParameter(), m5.PassAsParameter(),
m6.PassAsParameter(), m7.PassAsParameter());
}
};
template<typename Method, bool Owning, typename... Storages>
class nsRunnableMethodImpl
: public nsRunnableMethodTraits<Method, Owning>::base_type
{
typedef typename nsRunnableMethodTraits<Method, Owning>::class_type
ClassType;
nsRunnableMethodReceiver<ClassType, Owning> mReceiver;
Method mMethod;
nsRunnableMethodArguments<Storages...> mArgs;
public:
virtual ~nsRunnableMethodImpl() { Revoke(); };
template<typename... Args>
explicit nsRunnableMethodImpl(ClassType* aObj, Method aMethod,
Args&&... aArgs)
: mReceiver(aObj)
, mMethod(aMethod)
, mArgs(mozilla::Forward<Args>(aArgs)...)
{
static_assert(sizeof...(Storages) == sizeof...(Args), "Storages and Args should have equal sizes");
}
NS_IMETHOD Run()
{
if (MOZ_LIKELY(mReceiver.Get())) {
mArgs.apply(mReceiver.Get(), mMethod);
}
return NS_OK;
}
void Revoke() { mReceiver.Revoke(); }
};
// Use this template function like so:
//
// nsCOMPtr<nsIRunnable> event =
// NS_NewRunnableMethod(myObject, &MyClass::HandleEvent);
// NS_DispatchToCurrentThread(event);
//
// Statically enforced constraints:
// - myObject must be of (or implicitly convertible to) type MyClass
// - MyClass must defined AddRef and Release methods
//
template<typename PtrType, typename Method>
typename nsRunnableMethodTraits<Method, true>::base_type*
NS_NewRunnableMethod(PtrType aPtr, Method aMethod)
{
return new nsRunnableMethodImpl<Method, true>(aPtr, aMethod);
}
template<typename PtrType, typename Method>
typename nsRunnableMethodTraits<Method, false>::base_type*
NS_NewNonOwningRunnableMethod(PtrType&& aPtr, Method aMethod)
{
return new nsRunnableMethodImpl<Method, false>(aPtr, aMethod);
}
// Similar to NS_NewRunnableMethod. Call like so:
// nsCOMPtr<nsIRunnable> event =
// NS_NewRunnableMethodWithArg<Type>(myObject, &MyClass::HandleEvent, myArg);
// 'Type' is the stored type for the argument, see ParameterStorage for details.
template<typename Storage, typename Method, typename PtrType, typename Arg>
typename nsRunnableMethodTraits<Method, true>::base_type*
NS_NewRunnableMethodWithArg(PtrType&& aPtr, Method aMethod, Arg&& aArg)
{
return new nsRunnableMethodImpl<Method, true, Storage>(
aPtr, aMethod, mozilla::Forward<Arg>(aArg));
}
// Similar to NS_NewRunnableMethod. Call like so:
// nsCOMPtr<nsIRunnable> event =
// NS_NewRunnableMethodWithArg<Types,...>(myObject, &MyClass::HandleEvent, myArg1,...);
// 'Types' are the stored type for each argument, see ParameterStorage for details.
template<typename... Storages, typename Method, typename PtrType, typename... Args>
typename nsRunnableMethodTraits<Method, true>::base_type*
NS_NewRunnableMethodWithArgs(PtrType&& aPtr, Method aMethod, Args&&... aArgs)
{
static_assert(sizeof...(Storages) == sizeof...(Args),
"<Storages...> size should be equal to number of arguments");
return new nsRunnableMethodImpl<Method, true, Storages...>(
aPtr, aMethod, mozilla::Forward<Args>(aArgs)...);
}
template<typename... Storages, typename Method, typename PtrType, typename... Args>
typename nsRunnableMethodTraits<Method, false>::base_type*
NS_NewNonOwningRunnableMethodWithArgs(PtrType&& aPtr, Method aMethod,
Args&&... aArgs)
{
static_assert(sizeof...(Storages) == sizeof...(Args),
"<Storages...> size should be equal to number of arguments");
return new nsRunnableMethodImpl<Method, false, Storages...>(
aPtr, aMethod, mozilla::Forward<Args>(aArgs)...);
}
#endif // XPCOM_GLUE_AVOID_NSPR
// This class is designed to be used when you have an event class E that has a
// pointer back to resource class R. If R goes away while E is still pending,
// then it is important to "revoke" E so that it does not try use R after R has
// been destroyed. nsRevocableEventPtr makes it easy for R to manage such
// situations:
//
// class R;
//
// class E : public nsRunnable {
// public:
// void Revoke() {
// mResource = nullptr;
// }
// private:
// R *mResource;
// };
//
// class R {
// public:
// void EventHandled() {
// mEvent.Forget();
// }
// private:
// nsRevocableEventPtr<E> mEvent;
// };
//
// void R::PostEvent() {
// // Make sure any pending event is revoked.
// mEvent->Revoke();
//
// nsCOMPtr<nsIRunnable> event = new E();
// if (NS_SUCCEEDED(NS_DispatchToCurrentThread(event))) {
// // Keep pointer to event so we can revoke it.
// mEvent = event;
// }
// }
//
// NS_IMETHODIMP E::Run() {
// if (!mResource)
// return NS_OK;
// ...
// mResource->EventHandled();
// return NS_OK;
// }
//
template<class T>
class nsRevocableEventPtr
{
public:
nsRevocableEventPtr() : mEvent(nullptr) {}
~nsRevocableEventPtr() { Revoke(); }
const nsRevocableEventPtr& operator=(T* aEvent)
{
if (mEvent != aEvent) {
Revoke();
mEvent = aEvent;
}
return *this;
}
void Revoke()
{
if (mEvent) {
mEvent->Revoke();
mEvent = nullptr;
}
}
void Forget() { mEvent = nullptr; }
bool IsPending() { return mEvent != nullptr; }
T* get() { return mEvent; }
private:
// Not implemented
nsRevocableEventPtr(const nsRevocableEventPtr&);
nsRevocableEventPtr& operator=(const nsRevocableEventPtr&);
nsRefPtr<T> mEvent;
};
/**
* A simple helper to suffix thread pool name
* with incremental numbers.
*/
class nsThreadPoolNaming
{
public:
nsThreadPoolNaming() : mCounter(0) {}
/**
* Creates and sets next thread name as "<aPoolName> #<n>"
* on the specified thread. If no thread is specified (aThread
* is null) then the name is synchronously set on the current thread.
*/
void SetThreadPoolName(const nsACString& aPoolName,
nsIThread* aThread = nullptr);
private:
mozilla::Atomic<uint32_t> mCounter;
nsThreadPoolNaming(const nsThreadPoolNaming&) = delete;
void operator=(const nsThreadPoolNaming&) = delete;
};
/**
* Thread priority in most operating systems affect scheduling, not IO. This
* helper is used to set the current thread to low IO priority for the lifetime
* of the created object. You can only use this low priority IO setting within
* the context of the current thread.
*/
class MOZ_STACK_CLASS nsAutoLowPriorityIO
{
public:
nsAutoLowPriorityIO();
~nsAutoLowPriorityIO();
private:
bool lowIOPrioritySet;
#if defined(XP_MACOSX)
int oldPriority;
#endif
};
void
NS_SetMainThread();
/**
* Helpers for thread to report their status when compiled with Nuwa.
*/
#ifdef MOZILLA_INTERNAL_API
#ifdef MOZ_NUWA_PROCESS
extern void
NS_SetIgnoreStatusOfCurrentThread();
#else // MOZ_NUWA_PROCESS
inline void
NS_SetIgnoreStatusOfCurrentThread()
{
}
#endif // MOZ_NUWA_PROCESS
#endif // MOZILLA_INTERNAL_API
#endif // nsThreadUtils_h__