McRogueFace/deps_linux/SFML/System/Thread.hpp

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////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2018 Laurent Gomila (laurent@sfml-dev.org)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
// you must not claim that you wrote the original software.
// If you use this software in a product, an acknowledgment
// in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
// and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
////////////////////////////////////////////////////////////
#ifndef SFML_THREAD_HPP
#define SFML_THREAD_HPP
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/System/Export.hpp>
#include <SFML/System/NonCopyable.hpp>
#include <cstdlib>
namespace sf
{
namespace priv
{
class ThreadImpl;
struct ThreadFunc;
}
////////////////////////////////////////////////////////////
/// \brief Utility class to manipulate threads
///
////////////////////////////////////////////////////////////
class SFML_SYSTEM_API Thread : NonCopyable
{
public:
////////////////////////////////////////////////////////////
/// \brief Construct the thread from a functor with no argument
///
/// This constructor works for function objects, as well
/// as free functions.
///
/// Use this constructor for this kind of function:
/// \code
/// void function();
///
/// // --- or ----
///
/// struct Functor
/// {
/// void operator()();
/// };
/// \endcode
/// Note: this does *not* run the thread, use launch().
///
/// \param function Functor or free function to use as the entry point of the thread
///
////////////////////////////////////////////////////////////
template <typename F>
Thread(F function);
////////////////////////////////////////////////////////////
/// \brief Construct the thread from a functor with an argument
///
/// This constructor works for function objects, as well
/// as free functions.
/// It is a template, which means that the argument can
/// have any type (int, std::string, void*, Toto, ...).
///
/// Use this constructor for this kind of function:
/// \code
/// void function(int arg);
///
/// // --- or ----
///
/// struct Functor
/// {
/// void operator()(std::string arg);
/// };
/// \endcode
/// Note: this does *not* run the thread, use launch().
///
/// \param function Functor or free function to use as the entry point of the thread
/// \param argument argument to forward to the function
///
////////////////////////////////////////////////////////////
template <typename F, typename A>
Thread(F function, A argument);
////////////////////////////////////////////////////////////
/// \brief Construct the thread from a member function and an object
///
/// This constructor is a template, which means that you can
/// use it with any class.
/// Use this constructor for this kind of function:
/// \code
/// class MyClass
/// {
/// public:
///
/// void function();
/// };
/// \endcode
/// Note: this does *not* run the thread, use launch().
///
/// \param function Entry point of the thread
/// \param object Pointer to the object to use
///
////////////////////////////////////////////////////////////
template <typename C>
Thread(void(C::*function)(), C* object);
////////////////////////////////////////////////////////////
/// \brief Destructor
///
/// This destructor calls wait(), so that the internal thread
/// cannot survive after its sf::Thread instance is destroyed.
///
////////////////////////////////////////////////////////////
~Thread();
////////////////////////////////////////////////////////////
/// \brief Run the thread
///
/// This function starts the entry point passed to the
/// thread's constructor, and returns immediately.
/// After this function returns, the thread's function is
/// running in parallel to the calling code.
///
////////////////////////////////////////////////////////////
void launch();
////////////////////////////////////////////////////////////
/// \brief Wait until the thread finishes
///
/// This function will block the execution until the
/// thread's function ends.
/// Warning: if the thread function never ends, the calling
/// thread will block forever.
/// If this function is called from its owner thread, it
/// returns without doing anything.
///
////////////////////////////////////////////////////////////
void wait();
////////////////////////////////////////////////////////////
/// \brief Terminate the thread
///
/// This function immediately stops the thread, without waiting
/// for its function to finish.
/// Terminating a thread with this function is not safe,
/// and can lead to local variables not being destroyed
/// on some operating systems. You should rather try to make
/// the thread function terminate by itself.
///
////////////////////////////////////////////////////////////
void terminate();
private:
friend class priv::ThreadImpl;
////////////////////////////////////////////////////////////
/// \brief Internal entry point of the thread
///
/// This function is called by the thread implementation.
///
////////////////////////////////////////////////////////////
void run();
////////////////////////////////////////////////////////////
// Member data
////////////////////////////////////////////////////////////
priv::ThreadImpl* m_impl; ///< OS-specific implementation of the thread
priv::ThreadFunc* m_entryPoint; ///< Abstraction of the function to run
};
#include <SFML/System/Thread.inl>
} // namespace sf
#endif // SFML_THREAD_HPP
////////////////////////////////////////////////////////////
/// \class sf::Thread
/// \ingroup system
///
/// Threads provide a way to run multiple parts of the code
/// in parallel. When you launch a new thread, the execution
/// is split and both the new thread and the caller run
/// in parallel.
///
/// To use a sf::Thread, you construct it directly with the
/// function to execute as the entry point of the thread.
/// sf::Thread has multiple template constructors, which means
/// that you can use several types of entry points:
/// \li non-member functions with no argument
/// \li non-member functions with one argument of any type
/// \li functors with no argument (this one is particularly useful for compatibility with boost/std::%bind)
/// \li functors with one argument of any type
/// \li member functions from any class with no argument
///
/// The function argument, if any, is copied in the sf::Thread
/// instance, as well as the functor (if the corresponding
/// constructor is used). Class instances, however, are passed
/// by pointer so you must make sure that the object won't be
/// destroyed while the thread is still using it.
///
/// The thread ends when its function is terminated. If the
/// owner sf::Thread instance is destroyed before the
/// thread is finished, the destructor will wait (see wait())
///
/// Usage examples:
/// \code
/// // example 1: non member function with one argument
///
/// void threadFunc(int argument)
/// {
/// ...
/// }
///
/// sf::Thread thread(&threadFunc, 5);
/// thread.launch(); // start the thread (internally calls threadFunc(5))
/// \endcode
///
/// \code
/// // example 2: member function
///
/// class Task
/// {
/// public:
/// void run()
/// {
/// ...
/// }
/// };
///
/// Task task;
/// sf::Thread thread(&Task::run, &task);
/// thread.launch(); // start the thread (internally calls task.run())
/// \endcode
///
/// \code
/// // example 3: functor
///
/// struct Task
/// {
/// void operator()()
/// {
/// ...
/// }
/// };
///
/// sf::Thread thread(Task());
/// thread.launch(); // start the thread (internally calls operator() on the Task instance)
/// \endcode
///
/// Creating parallel threads of execution can be dangerous:
/// all threads inside the same process share the same memory space,
/// which means that you may end up accessing the same variable
/// from multiple threads at the same time. To prevent this
/// kind of situations, you can use mutexes (see sf::Mutex).
///
/// \see sf::Mutex
///
////////////////////////////////////////////////////////////