X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/9d133d8787de36494207675475eda4ef7a9f11f4..63cc5d9d20f997961881855811f6b6987679969d:/include/wx/thread.h diff --git a/include/wx/thread.h b/include/wx/thread.h index fcdfe7a743..b0bbc261f7 100644 --- a/include/wx/thread.h +++ b/include/wx/thread.h @@ -2,7 +2,8 @@ // Name: thread.h // Purpose: Thread API // Author: Guilhem Lavaux -// Modified by: +// Modified by: Vadim Zeitlin (modifications partly inspired by omnithreads +// package from Olivetti & Oracle Research Laboratory) // Created: 04/13/98 // RCS-ID: $Id$ // Copyright: (c) Guilhem Lavaux @@ -12,32 +13,40 @@ #ifndef __THREADH__ #define __THREADH__ -#ifdef __GNUG__ -#pragma interface "thread.h" -#endif - // ---------------------------------------------------------------------------- // headers // ---------------------------------------------------------------------------- + +// get the value of wxUSE_THREADS configuration flag #include "wx/setup.h" #if wxUSE_THREADS +/* otherwise we get undefined references for non-thread case (KB)*/ +#ifdef __GNUG__ + #pragma interface "thread.h" +#endif + +// Windows headers define it +#ifdef Yield + #undef Yield +#endif + #include "wx/module.h" // ---------------------------------------------------------------------------- // constants // ---------------------------------------------------------------------------- -typedef enum +typedef enum { wxMUTEX_NO_ERROR = 0, - wxMUTEX_DEAD_LOCK, // Mutex has been already locked by THE CALLING thread + wxMUTEX_DEAD_LOCK, // Mutex has been already locked by THE CALLING thread wxMUTEX_BUSY, // Mutex has been already locked by ONE thread wxMUTEX_UNLOCKED, wxMUTEX_MISC_ERROR } wxMutexError; -typedef enum +typedef enum { wxTHREAD_NO_ERROR = 0, // No error wxTHREAD_NO_RESOURCE, // No resource left to create a new thread @@ -46,10 +55,10 @@ typedef enum wxTHREAD_MISC_ERROR // Some other error } wxThreadError; -/* defines the interval of priority. */ -#define WXTHREAD_MIN_PRIORITY 0 -#define WXTHREAD_DEFAULT_PRIORITY 50 -#define WXTHREAD_MAX_PRIORITY 100 +// defines the interval of priority +#define WXTHREAD_MIN_PRIORITY 0u +#define WXTHREAD_DEFAULT_PRIORITY 50u +#define WXTHREAD_MAX_PRIORITY 100u // ---------------------------------------------------------------------------- // A mutex object is a synchronization object whose state is set to signaled @@ -61,28 +70,32 @@ typedef enum // you should consider wxMutexLocker whenever possible instead of directly // working with wxMutex class - it is safer class WXDLLEXPORT wxMutexInternal; -class WXDLLEXPORT wxMutex +class WXDLLEXPORT wxMutex { public: - // constructor & destructor - wxMutex(); - ~wxMutex(); + // constructor & destructor + wxMutex(); + ~wxMutex(); - // Lock the mutex. - wxMutexError Lock(); - // Try to lock the mutex: if it can't, returns immediately with an error. - wxMutexError TryLock(); - // Unlock the mutex. - wxMutexError Unlock(); + // Lock the mutex. + wxMutexError Lock(); + // Try to lock the mutex: if it can't, returns immediately with an error. + wxMutexError TryLock(); + // Unlock the mutex. + wxMutexError Unlock(); - // Returns true if the mutex is locked. - bool IsLocked() const { return (m_locked > 0); } + // Returns true if the mutex is locked. + bool IsLocked() const { return (m_locked > 0); } protected: - friend class wxCondition; + friend class wxCondition; + + // no assignment operator nor copy ctor + wxMutex(const wxMutex&); + wxMutex& operator=(const wxMutex&); - int m_locked; - wxMutexInternal *p_internal; + int m_locked; + wxMutexInternal *p_internal; }; // a helper class which locks the mutex in the ctor and unlocks it in the dtor: @@ -92,18 +105,24 @@ class WXDLLEXPORT wxMutexLocker { public: // lock the mutex in the ctor - wxMutexLocker(wxMutex *mutex) - { m_isOk = mutex && ((m_mutex = mutex)->Lock() == wxMUTEX_NO_ERROR); } + wxMutexLocker(wxMutex& mutex) : m_mutex(mutex) + { m_isOk = m_mutex.Lock() == wxMUTEX_NO_ERROR; } // returns TRUE if mutex was successfully locked in ctor - bool IsOk() const { return m_isOk; } + bool IsOk() const + { return m_isOk; } // unlock the mutex in dtor - ~wxMutexLocker() { if ( IsOk() ) m_mutex->Unlock(); } + ~wxMutexLocker() + { if ( IsOk() ) m_mutex.Unlock(); } private: + // no assignment operator nor copy ctor + wxMutexLocker(const wxMutexLocker&); + wxMutexLocker& operator=(const wxMutexLocker&); + bool m_isOk; - wxMutex *m_mutex; + wxMutex& m_mutex; }; // ---------------------------------------------------------------------------- @@ -113,37 +132,60 @@ private: // mutexes // ---------------------------------------------------------------------------- +// in order to avoid any overhead under !MSW make all wxCriticalSection class +// functions inline - but this can't be done under MSW +#ifdef __WXMSW__ + class WXDLLEXPORT wxCriticalSectionInternal; + #define WXCRITICAL_INLINE +#else // !MSW + #define WXCRITICAL_INLINE inline +#endif // MSW/!MSW + // you should consider wxCriticalSectionLocker whenever possible instead of // directly working with wxCriticalSection class - it is safer -class WXDLLEXPORT wxCriticalSectionInternal; class WXDLLEXPORT wxCriticalSection { public: // ctor & dtor - wxCriticalSection(); - ~wxCriticalSection(); + WXCRITICAL_INLINE wxCriticalSection(); + WXCRITICAL_INLINE ~wxCriticalSection(); // enter the section (the same as locking a mutex) - void Enter(); + WXCRITICAL_INLINE void Enter(); // leave the critical section (same as unlocking a mutex) - void Leave(); + WXCRITICAL_INLINE void Leave(); private: + // no assignment operator nor copy ctor + wxCriticalSection(const wxCriticalSection&); + wxCriticalSection& operator=(const wxCriticalSection&); + +#ifdef __WXMSW__ wxCriticalSectionInternal *m_critsect; +#else // !MSW + wxMutex m_mutex; +#endif // MSW/!MSW }; +// keep your preprocessor name space clean +#undef WXCRITICAL_INLINE + // wxCriticalSectionLocker is the same to critical sections as wxMutexLocker is // to th mutexes class WXDLLEXPORT wxCriticalSectionLocker { public: - wxCriticalSectionLocker(wxCriticalSection *critsect) - { (m_critsect = critsect)->Enter(); } + wxCriticalSectionLocker(wxCriticalSection& critsect) : m_critsect(critsect) + { m_critsect.Enter(); } ~wxCriticalSectionLocker() - { m_critsect->Leave(); } + { m_critsect.Leave(); } private: - wxCriticalSection *m_critsect; + // no assignment operator nor copy ctor + wxCriticalSectionLocker(const wxCriticalSectionLocker&); + wxCriticalSectionLocker& operator=(const wxCriticalSectionLocker&); + + wxCriticalSection& m_critsect; }; // ---------------------------------------------------------------------------- @@ -151,7 +193,7 @@ private: // ---------------------------------------------------------------------------- class wxConditionInternal; -class WXDLLEXPORT wxCondition +class WXDLLEXPORT wxCondition { public: // constructor & destructor @@ -175,70 +217,129 @@ private: // Thread management class // ---------------------------------------------------------------------------- +// FIXME Thread termination model is still unclear. Delete() should probably +// have a timeout after which the thread must be Kill()ed. + +// NB: in the function descriptions the words "this thread" mean the thread +// created by the wxThread object while "main thread" is the thread created +// during the process initialization (a.k.a. the GUI thread) class wxThreadInternal; -class WXDLLEXPORT wxThread +class WXDLLEXPORT wxThread { public: - // constructor & destructor. - wxThread(); - virtual ~wxThread(); - - // Create a new thread, this method should check there is only one thread - // running by object. - wxThreadError Create(); - - // Destroys the thread immediately if the defer flag isn't true. - wxThreadError Destroy(); - - // Pause a running thread - wxThreadError Pause(); + // 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 leting 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); + + // default constructor + wxThread(); + + // function that change the thread state + // create a new thread - call Run() to start it + wxThreadError Create(); + + // 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 + // freeing its memory. This function should also be called if the + // Create() or Run() fails to free memory (otherwise it will be done by + // the thread itself when it terminates). The return value is the + // thread exit code if the thread was gracefully terminated, 0 if it + // wasn't running and -1 if an error occured. + ExitCode Delete(); + + // kills the thread without giving it any chance to clean up - should + // not be used in 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 thread was + // killed (i.e. no errors occured). + wxThreadError Kill(); + + // pause a running thread + 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; + + // Get the thread ID - a platform dependent number which uniquely + // identifies a thread inside a process + unsigned long GetID() 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; + + // 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() { } - // Resume a paused thread - wxThreadError Resume(); - - // Switches on the defer flag. - void DeferDestroy(bool on); - - // Waits for the termination of the thread. - void *Join(); - - // Sets the priority to "prio". (Warning: The priority can only be set before - // the thread is created) - void SetPriority(int prio); - // Get the current priority. - int GetPriority() const; - - // Get the thread ID - unsigned long GetID() const; - - // Returns true if the thread is alive. - 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 { return IsAlive() && !IsRunning(); } - - // Returns true if current thread is the main thread (aka the GUI thread) - static bool IsMain(); +protected: + // 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()! + bool TestDestroy(); - // Called when thread exits. - virtual void OnExit(); + // exits from the current thread - can be called only from this thread + void Exit(void *exitcode = 0); -protected: - // Returns TRUE if the thread was asked to terminate - bool TestDestroy(); + // destructor is private - user code can't delete thread objects, they will + // auto-delete themselves (and thus must be always allocated on the heap). + // Use Delete() or Kill() instead. + // + // NB: derived classes dtors shouldn't be public neither! + virtual ~wxThread(); - // Exits from the current thread. - void Exit(void *status = NULL); + // entry point for the thread - called by Run() and executes in the context + // of this thread. + virtual void *Entry() = 0; private: - // Entry point for the thread. - virtual void *Entry() = 0; + // no copy ctor/assignment operator + wxThread(const wxThread&); + wxThread& operator=(const wxThread&); -private: - friend class wxThreadInternal; + friend class wxThreadInternal; - wxThreadInternal *p_internal; + // the (platform-dependent) thread class implementation + wxThreadInternal *p_internal; + + // protects access to any methods of wxThreadInternal object + wxCriticalSection m_critsect; }; // ---------------------------------------------------------------------------- @@ -251,10 +352,49 @@ void WXDLLEXPORT wxMutexGuiLeave(); #else // !wxUSE_THREADS +#include // for WXDLLEXPORT + // no thread support inline void WXDLLEXPORT wxMutexGuiEnter() { } inline void WXDLLEXPORT wxMutexGuiLeave() { } #endif // wxUSE_THREADS +// automatically unlock GUI mutex in dtor +class WXDLLEXPORT wxMutexGuiLocker +{ +public: + wxMutexGuiLocker() { wxMutexGuiEnter(); } + ~wxMutexGuiLocker() { wxMutexGuiLeave(); } +}; + +// ----------------------------------------------------------------------------- +// implementation only until the end of file +// ----------------------------------------------------------------------------- +#if wxUSE_THREADS +#ifdef __WXMSW__ + // 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 WXDLLEXPORT wxMutexGuiLeaveOrEnter(); + + // returns TRUE if the main thread has GUI lock + extern bool WXDLLEXPORT wxGuiOwnedByMainThread(); + + // wakes up the main thread if it's sleeping inside ::GetMessage() + extern void WXDLLEXPORT wxWakeUpMainThread(); + + // return TRUE if the main thread is waiting for some other to terminate: + // wxApp then should block all "dangerous" messages + extern bool WXDLLEXPORT wxIsWaitingForThread(); +#else // !MSW + // implement wxCriticalSection using mutexes + inline wxCriticalSection::wxCriticalSection() { } + inline wxCriticalSection::~wxCriticalSection() { } + + inline void wxCriticalSection::Enter() { (void)m_mutex.Lock(); } + inline void wxCriticalSection::Leave() { (void)m_mutex.Unlock(); } +#endif // MSW/!MSW +#endif // wxUSE_THREADS + #endif // __THREADH__