+
+class WXDLLIMPEXP_BASE wxThread
+{
+public:
+ // the return type for the thread function
+ typedef void *ExitCode;
+
+ // static functions
+ // Returns the wxThread object for the calling thread. NULL is returned
+ // if the caller is the main thread (but it's recommended to use
+ // IsMain() and only call This() for threads other than the main one
+ // because NULL is also returned on error). If the thread wasn't
+ // created with wxThread class, the returned value is undefined.
+ static wxThread *This();
+
+ // Returns true if current thread is the main thread.
+ static bool IsMain();
+
+ // Release the rest of our time slice letting the other threads run
+ static void Yield();
+
+ // Sleep during the specified period of time in milliseconds
+ //
+ // NB: at least under MSW worker threads can not call ::wxSleep()!
+ static void Sleep(unsigned long milliseconds);
+
+ // get the number of system CPUs - useful with SetConcurrency()
+ // (the "best" value for it is usually number of CPUs + 1)
+ //
+ // Returns -1 if unknown, number of CPUs otherwise
+ static int GetCPUCount();
+
+ // Get the platform specific thread ID and return as a long. This
+ // can be used to uniquely identify threads, even if they are not
+ // wxThreads. This is used by wxPython.
+ static wxThreadIdType GetCurrentId();
+
+ // sets the concurrency level: this is, roughly, the number of threads
+ // the system tries to schedule to run in parallel. 0 means the
+ // default value (usually acceptable, but may not yield the best
+ // performance for this process)
+ //
+ // Returns true on success, false otherwise (if not implemented, for
+ // example)
+ static bool SetConcurrency(size_t level);
+
+ // constructor only creates the C++ thread object and doesn't create (or
+ // start) the real thread
+ wxThread(wxThreadKind kind = wxTHREAD_DETACHED);
+
+ // functions that change the thread state: all these can only be called
+ // from _another_ thread (typically the thread that created this one, e.g.
+ // the main thread), not from the thread itself
+
+ // create a new thread and optionally set the stack size on
+ // platforms that support that - call Run() to start it
+ // (special cased for watcom which won't accept 0 default)
+
+ wxThreadError Create(unsigned int stackSize = 0);
+
+ // starts execution of the thread - from the moment Run() is called
+ // the execution of wxThread::Entry() may start at any moment, caller
+ // shouldn't suppose that it starts after (or before) Run() returns.
+ wxThreadError Run();
+
+ // stops the thread if it's running and deletes the wxThread object if
+ // this is a detached thread freeing its memory - otherwise (for
+ // joinable threads) you still need to delete wxThread object
+ // yourself.
+ //
+ // this function only works if the thread calls TestDestroy()
+ // periodically - the thread will only be deleted the next time it
+ // does it!
+ //
+ // will fill the rc pointer with the thread exit code if it's !NULL
+ wxThreadError Delete(ExitCode *rc = (ExitCode *)NULL);
+
+ // waits for a joinable thread to finish and returns its exit code
+ //
+ // Returns (ExitCode)-1 on error (for example, if the thread is not
+ // joinable)
+ ExitCode Wait();
+
+ // kills the thread without giving it any chance to clean up - should
+ // not be used under normal circumstances, use Delete() instead.
+ // It is a dangerous function that should only be used in the most
+ // extreme cases!
+ //
+ // The wxThread object is deleted by Kill() if the thread is
+ // detachable, but you still have to delete it manually for joinable
+ // threads.
+ wxThreadError Kill();
+
+ // pause a running thread: as Delete(), this only works if the thread
+ // calls TestDestroy() regularly
+ wxThreadError Pause();
+
+ // resume a paused thread
+ wxThreadError Resume();
+
+ // priority
+ // Sets the priority to "prio": see WXTHREAD_XXX_PRIORITY constants
+ //
+ // NB: the priority can only be set before the thread is created
+ void SetPriority(unsigned int prio);
+
+ // Get the current priority.
+ unsigned int GetPriority() const;
+
+ // thread status inquiries
+ // Returns true if the thread is alive: i.e. running or suspended
+ bool IsAlive() const;
+ // Returns true if the thread is running (not paused, not killed).
+ bool IsRunning() const;
+ // Returns true if the thread is suspended
+ bool IsPaused() const;
+
+ // is the thread of detached kind?
+ bool IsDetached() const { return m_isDetached; }
+
+ // Get the thread ID - a platform dependent number which uniquely
+ // identifies a thread inside a process
+ wxThreadIdType GetId() const;
+
+ // called when the thread exits - in the context of this thread
+ //
+ // NB: this function will not be called if the thread is Kill()ed
+ virtual void OnExit() { }
+
+ // Returns true if the thread was asked to terminate: this function should
+ // be called by the thread from time to time, otherwise the main thread
+ // will be left forever in Delete()!
+ virtual bool TestDestroy();
+
+ // dtor is public, but the detached threads should never be deleted - use
+ // Delete() instead (or leave the thread terminate by itself)
+ virtual ~wxThread();
+
+protected:
+ // exits from the current thread - can be called only from this thread
+ void Exit(ExitCode exitcode = 0);
+
+ // entry point for the thread - called by Run() and executes in the context
+ // of this thread.
+ virtual void *Entry() = 0;
+
+private:
+ // no copy ctor/assignment operator
+ wxThread(const wxThread&);
+ wxThread& operator=(const wxThread&);
+
+ friend class wxThreadInternal;
+
+ // the (platform-dependent) thread class implementation
+ wxThreadInternal *m_internal;
+
+ // protects access to any methods of wxThreadInternal object
+ wxCriticalSection m_critsect;
+
+ // true if the thread is detached, false if it is joinable
+ bool m_isDetached;
+};
+
+// wxThreadHelperThread class
+// --------------------------
+
+class WXDLLIMPEXP_BASE wxThreadHelperThread : public wxThread
+{
+public:
+ // constructor only creates the C++ thread object and doesn't create (or
+ // start) the real thread
+ wxThreadHelperThread(wxThreadHelper& owner, wxThreadKind kind)
+ : wxThread(kind), m_owner(owner)
+ { }
+
+protected:
+ // entry point for the thread -- calls Entry() in owner.
+ virtual void *Entry();
+
+private:
+ // the owner of the thread
+ wxThreadHelper& m_owner;
+
+ // no copy ctor/assignment operator
+ wxThreadHelperThread(const wxThreadHelperThread&);
+ wxThreadHelperThread& operator=(const wxThreadHelperThread&);
+};
+
+// ----------------------------------------------------------------------------
+// wxThreadHelper: this class implements the threading logic to run a
+// background task in another object (such as a window). It is a mix-in: just
+// derive from it to implement a threading background task in your class.
+// ----------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxThreadHelper
+{
+private:
+ void KillThread()
+ {
+ // If detached thread is about to finish, it will set
+ // m_thread to NULL so don't delete it then
+ // But if KillThread is called before detached thread
+ // sets it to NULL, then the thread object still
+ // exists and can be killed
+ wxCriticalSectionLocker locker(m_critSection);
+
+ if ( m_thread )
+ {
+ m_thread->Kill();
+
+ if ( m_kind == wxTHREAD_JOINABLE )
+ delete m_thread;
+
+ m_thread = NULL;
+ }
+ }
+
+public:
+ // constructor only initializes m_thread to NULL
+ wxThreadHelper(wxThreadKind kind = wxTHREAD_JOINABLE)
+ : m_thread(NULL), m_kind(kind) { }
+
+ // destructor deletes m_thread
+ virtual ~wxThreadHelper() { KillThread(); }
+
+ // create a new thread (and optionally set the stack size on platforms that
+ // support/need that), call Run() to start it
+ wxThreadError Create(unsigned int stackSize = 0)
+ {
+ KillThread();
+
+ m_thread = new wxThreadHelperThread(*this, m_kind);
+
+ return m_thread->Create(stackSize);
+ }
+
+ // entry point for the thread - called by Run() and executes in the context
+ // of this thread.
+ virtual void *Entry() = 0;
+
+ // returns a pointer to the thread which can be used to call Run()
+ wxThread *GetThread() const
+ {
+ wxCriticalSectionLocker locker((wxCriticalSection&)m_critSection);
+
+ wxThread* thread = m_thread;
+
+ return thread;
+ }
+
+protected:
+ wxThread *m_thread;
+ wxThreadKind m_kind;
+ wxCriticalSection m_critSection; // To guard the m_thread variable
+
+ friend class wxThreadHelperThread;
+};
+
+// call Entry() in owner, put it down here to avoid circular declarations
+inline void *wxThreadHelperThread::Entry()
+{
+ void * const result = m_owner.Entry();
+
+ wxCriticalSectionLocker locker(m_owner.m_critSection);
+
+ // Detached thread will be deleted after returning, so make sure
+ // wxThreadHelper::GetThread will not return an invalid pointer.
+ // And that wxThreadHelper::KillThread will not try to kill
+ // an already deleted thread
+ if ( m_owner.m_kind == wxTHREAD_DETACHED )
+ m_owner.m_thread = NULL;
+
+ return result;
+}
+
+// ----------------------------------------------------------------------------
+// Automatic initialization
+// ----------------------------------------------------------------------------
+
+// GUI mutex handling.
+void WXDLLIMPEXP_BASE wxMutexGuiEnter();
+void WXDLLIMPEXP_BASE wxMutexGuiLeave();
+
+// macros for entering/leaving critical sections which may be used without
+// having to take them inside "#if wxUSE_THREADS"
+#define wxENTER_CRIT_SECT(cs) (cs).Enter()
+#define wxLEAVE_CRIT_SECT(cs) (cs).Leave()
+#define wxCRIT_SECT_DECLARE(cs) static wxCriticalSection cs
+#define wxCRIT_SECT_DECLARE_MEMBER(cs) wxCriticalSection cs
+#define wxCRIT_SECT_LOCKER(name, cs) wxCriticalSectionLocker name(cs)
+
+// function for checking if we're in the main thread which may be used whether
+// wxUSE_THREADS is 0 or 1
+inline bool wxIsMainThread() { return wxThread::IsMain(); }
+
+#else // !wxUSE_THREADS
+
+// no thread support
+inline void wxMutexGuiEnter() { }
+inline void wxMutexGuiLeave() { }
+
+// macros for entering/leaving critical sections which may be used without
+// having to take them inside "#if wxUSE_THREADS"
+// (the implementation uses dummy structs to force semicolon after the macro)
+#define wxENTER_CRIT_SECT(cs) do {} while (0)
+#define wxLEAVE_CRIT_SECT(cs) do {} while (0)
+#define wxCRIT_SECT_DECLARE(cs) struct wxDummyCS##cs
+#define wxCRIT_SECT_DECLARE_MEMBER(cs) struct wxDummyCSMember##cs
+#define wxCRIT_SECT_LOCKER(name, cs) struct wxDummyCSLocker##name
+
+// if there is only one thread, it is always the main one
+inline bool wxIsMainThread() { return true; }
+
+#endif // wxUSE_THREADS/!wxUSE_THREADS
+
+// mark part of code as being a critical section: this macro declares a
+// critical section with the given name and enters it immediately and leaves
+// it at the end of the current scope
+//
+// example:
+//
+// int Count()
+// {
+// static int s_counter = 0;
+//
+// wxCRITICAL_SECTION(counter);
+//
+// return ++s_counter;
+// }
+//
+// this function is MT-safe in presence of the threads but there is no
+// overhead when the library is compiled without threads
+#define wxCRITICAL_SECTION(name) \
+ wxCRIT_SECT_DECLARE(s_cs##name); \
+ wxCRIT_SECT_LOCKER(cs##name##Locker, s_cs##name)
+
+// automatically lock GUI mutex in ctor and unlock it in dtor
+class WXDLLIMPEXP_BASE wxMutexGuiLocker
+{
+public:
+ wxMutexGuiLocker() { wxMutexGuiEnter(); }
+ ~wxMutexGuiLocker() { wxMutexGuiLeave(); }
+};
+
+// -----------------------------------------------------------------------------
+// implementation only until the end of file
+// -----------------------------------------------------------------------------
+
+#if wxUSE_THREADS
+
+#if defined(__WXMSW__) || defined(__WXMAC__) || defined(__OS2__) || defined(__EMX__)
+ // unlock GUI if there are threads waiting for and lock it back when
+ // there are no more of them - should be called periodically by the main
+ // thread
+ extern void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter();
+
+ // returns true if the main thread has GUI lock
+ extern bool WXDLLIMPEXP_BASE wxGuiOwnedByMainThread();
+
+ // wakes up the main thread if it's sleeping inside ::GetMessage()
+ extern void WXDLLIMPEXP_BASE wxWakeUpMainThread();
+
+ // return true if the main thread is waiting for some other to terminate:
+ // wxApp then should block all "dangerous" messages
+ extern bool WXDLLIMPEXP_BASE wxIsWaitingForThread();
+#endif // MSW, Mac, OS/2
+
+#endif // wxUSE_THREADS
+
+#endif // _WX_THREAD_H_
projects / wxWidgets.git / blobdiff