ClickHouse/contrib/libpoco/Foundation/include/Poco/Thread.h

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//
// Thread.h
//
// $Id: //poco/1.4/Foundation/include/Poco/Thread.h#3 $
//
// Library: Foundation
// Package: Threading
// Module: Thread
//
// Definition of the Thread class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_Thread_INCLUDED
#define Foundation_Thread_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/Event.h"
#include "Poco/Mutex.h"
#if defined(POCO_OS_FAMILY_WINDOWS)
#if defined(_WIN32_WCE)
#include "Poco/Thread_WINCE.h"
#else
#include "Poco/Thread_WIN32.h"
#endif
#elif defined(POCO_VXWORKS)
#include "Poco/Thread_VX.h"
#else
#include "Poco/Thread_POSIX.h"
#endif
namespace Poco {
class Runnable;
class ThreadLocalStorage;
class Foundation_API Thread: private ThreadImpl
/// This class implements a platform-independent
/// wrapper to an operating system thread.
///
/// Every Thread object gets a unique (within
/// its process) numeric thread ID.
/// Furthermore, a thread can be assigned a name.
/// The name of a thread can be changed at any time.
{
public:
typedef ThreadImpl::TIDImpl TID;
using ThreadImpl::Callable;
enum Priority
/// Thread priorities.
{
PRIO_LOWEST = PRIO_LOWEST_IMPL, /// The lowest thread priority.
PRIO_LOW = PRIO_LOW_IMPL, /// A lower than normal thread priority.
PRIO_NORMAL = PRIO_NORMAL_IMPL, /// The normal thread priority.
PRIO_HIGH = PRIO_HIGH_IMPL, /// A higher than normal thread priority.
PRIO_HIGHEST = PRIO_HIGHEST_IMPL /// The highest thread priority.
};
enum Policy
{
POLICY_DEFAULT = POLICY_DEFAULT_IMPL
};
Thread();
/// Creates a thread. Call start() to start it.
Thread(const std::string& name);
/// Creates a named thread. Call start() to start it.
~Thread();
/// Destroys the thread.
int id() const;
/// Returns the unique thread ID of the thread.
TID tid() const;
/// Returns the native thread ID of the thread.
std::string name() const;
/// Returns the name of the thread.
std::string getName() const;
/// Returns the name of the thread.
void setName(const std::string& name);
/// Sets the name of the thread.
void setPriority(Priority prio);
/// Sets the thread's priority.
///
/// Some platform only allow changing a thread's priority
/// if the process has certain privileges.
Priority getPriority() const;
/// Returns the thread's priority.
void setOSPriority(int prio, int policy = POLICY_DEFAULT);
/// Sets the thread's priority, using an operating system specific
/// priority value. Use getMinOSPriority() and getMaxOSPriority() to
/// obtain mininum and maximum priority values. Additionally,
/// a scheduling policy can be specified. The policy is currently
/// only used on POSIX platforms where the values SCHED_OTHER (default),
/// SCHED_FIFO and SCHED_RR are supported.
int getOSPriority() const;
/// Returns the thread's priority, expressed as an operating system
/// specific priority value.
///
/// May return 0 if the priority has not been explicitly set.
static int getMinOSPriority(int policy = POLICY_DEFAULT);
/// Returns the minimum operating system-specific priority value,
/// which can be passed to setOSPriority() for the given policy.
static int getMaxOSPriority(int policy = POLICY_DEFAULT);
/// Returns the maximum operating system-specific priority value,
/// which can be passed to setOSPriority() for the given policy.
void setStackSize(int size);
/// Sets the thread's stack size in bytes.
/// Setting the stack size to 0 will use the default stack size.
/// Typically, the real stack size is rounded up to the nearest
/// page size multiple.
int getStackSize() const;
/// Returns the thread's stack size in bytes.
/// If the default stack size is used, 0 is returned.
void start(Runnable& target);
/// Starts the thread with the given target.
///
/// Note that the given Runnable object must remain
/// valid during the entire lifetime of the thread, as
/// only a reference to it is stored internally.
void start(Callable target, void* pData = 0);
/// Starts the thread with the given target and parameter.
template <class Functor>
void startFunc(Functor fn)
/// Starts the thread with the given functor object or lambda.
{
startImpl(new FunctorRunnable<Functor>(fn));
}
void join();
/// Waits until the thread completes execution.
/// If multiple threads try to join the same
/// thread, the result is undefined.
void join(long milliseconds);
/// Waits for at most the given interval for the thread
/// to complete. Throws a TimeoutException if the thread
/// does not complete within the specified time interval.
bool tryJoin(long milliseconds);
/// Waits for at most the given interval for the thread
/// to complete. Returns true if the thread has finished,
/// false otherwise.
bool isRunning() const;
/// Returns true if the thread is running.
static bool trySleep(long milliseconds);
/// Starts an interruptible sleep. When trySleep() is called,
/// the thread will remain suspended until:
/// - the timeout expires or
/// - wakeUp() is called
///
/// Function returns true if sleep attempt was completed, false
/// if sleep was interrupted by a wakeUp() call.
/// A frequent scenario where trySleep()/wakeUp() pair of functions
/// is useful is with threads spending most of the time idle,
/// with periodic activity between the idle times; trying to sleep
/// (as opposed to sleeping) allows immediate ending of idle thread
/// from the outside.
///
/// The trySleep() and wakeUp() calls should be used with
/// understanding that the suspended state is not a true sleep,
/// but rather a state of waiting for an event, with timeout
/// expiration. This makes order of calls significant; calling
/// wakeUp() before calling trySleep() will prevent the next
/// trySleep() call to actually suspend the thread (which, in
/// some scenarios, may be desirable behavior).
void wakeUp();
/// Wakes up the thread which is in the state of interruptible
/// sleep. For threads that are not suspended, calling this
/// function has the effect of preventing the subsequent
/// trySleep() call to put thread in a suspended state.
static void sleep(long milliseconds);
/// Suspends the current thread for the specified
/// amount of time.
static void yield();
/// Yields cpu to other threads.
static Thread* current();
/// Returns the Thread object for the currently active thread.
/// If the current thread is the main thread, 0 is returned.
static TID currentTid();
/// Returns the native thread ID for the current thread.
protected:
ThreadLocalStorage& tls();
/// Returns a reference to the thread's local storage.
void clearTLS();
/// Clears the thread's local storage.
std::string makeName();
/// Creates a unique name for a thread.
static int uniqueId();
/// Creates and returns a unique id for a thread.
template <class Functor>
class FunctorRunnable: public Runnable
{
public:
FunctorRunnable(const Functor& functor):
_functor(functor)
{
}
~FunctorRunnable()
{
}
void run()
{
_functor();
}
private:
Functor _functor;
};
private:
Thread(const Thread&);
Thread& operator = (const Thread&);
int _id;
std::string _name;
ThreadLocalStorage* _pTLS;
Event _event;
mutable FastMutex _mutex;
friend class ThreadLocalStorage;
friend class PooledThread;
};
//
// inlines
//
inline Thread::TID Thread::tid() const
{
return tidImpl();
}
inline int Thread::id() const
{
return _id;
}
inline std::string Thread::name() const
{
FastMutex::ScopedLock lock(_mutex);
return _name;
}
inline std::string Thread::getName() const
{
FastMutex::ScopedLock lock(_mutex);
return _name;
}
inline bool Thread::isRunning() const
{
return isRunningImpl();
}
inline void Thread::sleep(long milliseconds)
{
sleepImpl(milliseconds);
}
inline void Thread::yield()
{
yieldImpl();
}
inline Thread* Thread::current()
{
return static_cast<Thread*>(currentImpl());
}
inline void Thread::setOSPriority(int prio, int policy)
{
setOSPriorityImpl(prio, policy);
}
inline int Thread::getOSPriority() const
{
return getOSPriorityImpl();
}
inline int Thread::getMinOSPriority(int policy)
{
return ThreadImpl::getMinOSPriorityImpl(policy);
}
inline int Thread::getMaxOSPriority(int policy)
{
return ThreadImpl::getMaxOSPriorityImpl(policy);
}
inline void Thread::setStackSize(int size)
{
setStackSizeImpl(size);
}
inline int Thread::getStackSize() const
{
return getStackSizeImpl();
}
inline Thread::TID Thread::currentTid()
{
return currentTidImpl();
}
} // namespace Poco
#endif // Foundation_Thread_INCLUDED