X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/13d068d93e1e2bef0cb86225feb9355b4f6b4da9..661698e54f2bc599dc1a961ffbae08ccdd6b9b97:/include/wx/thread.h diff --git a/include/wx/thread.h b/include/wx/thread.h index 7e575b2f1e..1a1d0c27b4 100644 --- a/include/wx/thread.h +++ b/include/wx/thread.h @@ -1,5 +1,5 @@ ///////////////////////////////////////////////////////////////////////////// -// Name: thread.h +// Name: wx/thread.h // Purpose: Thread API // Author: Guilhem Lavaux // Modified by: Vadim Zeitlin (modifications partly inspired by omnithreads @@ -10,41 +10,49 @@ // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// -#ifndef __THREADH__ -#define __THREADH__ +#ifndef _WX_THREAD_H_ +#define _WX_THREAD_H_ // ---------------------------------------------------------------------------- // headers // ---------------------------------------------------------------------------- // get the value of wxUSE_THREADS configuration flag -#include "wx/setup.h" +#include "wx/defs.h" #if wxUSE_THREADS -// only for wxUSE_THREADS - otherwise we'd get undefined symbols -#ifdef __GNUG__ - #pragma interface "thread.h" -#endif - -// Windows headers define it -#ifdef Yield - #undef Yield -#endif - -#include "wx/module.h" - // ---------------------------------------------------------------------------- // constants // ---------------------------------------------------------------------------- enum wxMutexError { - wxMUTEX_NO_ERROR = 0, - 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 + wxMUTEX_NO_ERROR = 0, // operation completed successfully + wxMUTEX_INVALID, // mutex hasn't been initialized + wxMUTEX_DEAD_LOCK, // mutex is already locked by the calling thread + wxMUTEX_BUSY, // mutex is already locked by another thread + wxMUTEX_UNLOCKED, // attempt to unlock a mutex which is not locked + wxMUTEX_TIMEOUT, // LockTimeout() has timed out + wxMUTEX_MISC_ERROR // any other error +}; + +enum wxCondError +{ + wxCOND_NO_ERROR = 0, + wxCOND_INVALID, + wxCOND_TIMEOUT, // WaitTimeout() has timed out + wxCOND_MISC_ERROR +}; + +enum wxSemaError +{ + wxSEMA_NO_ERROR = 0, + wxSEMA_INVALID, // semaphore hasn't been initialized successfully + wxSEMA_BUSY, // returned by TryWait() if Wait() would block + wxSEMA_TIMEOUT, // returned by WaitTimeout() + wxSEMA_OVERFLOW, // Post() would increase counter past the max + wxSEMA_MISC_ERROR }; enum wxThreadError @@ -63,14 +71,61 @@ enum wxThreadKind wxTHREAD_JOINABLE }; -// defines the interval of priority +enum wxThreadWait +{ + wxTHREAD_WAIT_BLOCK, + wxTHREAD_WAIT_YIELD, // process events while waiting; MSW only + + // For compatibility reasons we use wxTHREAD_WAIT_YIELD by default as this + // was the default behaviour of wxMSW 2.8 but it should be avoided as it's + // dangerous and not portable. +#if WXWIN_COMPATIBILITY_2_8 + wxTHREAD_WAIT_DEFAULT = wxTHREAD_WAIT_YIELD +#else + wxTHREAD_WAIT_DEFAULT = wxTHREAD_WAIT_BLOCK +#endif +}; + +// Obsolete synonyms for wxPRIORITY_XXX for backwards compatibility-only enum { - WXTHREAD_MIN_PRIORITY = 0u, - WXTHREAD_DEFAULT_PRIORITY = 50u, - WXTHREAD_MAX_PRIORITY = 100u + WXTHREAD_MIN_PRIORITY = wxPRIORITY_MIN, + WXTHREAD_DEFAULT_PRIORITY = wxPRIORITY_DEFAULT, + WXTHREAD_MAX_PRIORITY = wxPRIORITY_MAX }; +// There are 2 types of mutexes: normal mutexes and recursive ones. The attempt +// to lock a normal mutex by a thread which already owns it results in +// undefined behaviour (it always works under Windows, it will almost always +// result in a deadlock under Unix). Locking a recursive mutex in such +// situation always succeeds and it must be unlocked as many times as it has +// been locked. +// +// However recursive mutexes have several important drawbacks: first, in the +// POSIX implementation, they're less efficient. Second, and more importantly, +// they CAN NOT BE USED WITH CONDITION VARIABLES under Unix! Using them with +// wxCondition will work under Windows and some Unices (notably Linux) but will +// deadlock under other Unix versions (e.g. Solaris). As it might be difficult +// to ensure that a recursive mutex is not used with wxCondition, it is a good +// idea to avoid using recursive mutexes at all. Also, the last problem with +// them is that some (older) Unix versions don't support this at all -- which +// results in a configure warning when building and a deadlock when using them. +enum wxMutexType +{ + // normal mutex: try to always use this one + wxMUTEX_DEFAULT, + + // recursive mutex: don't use these ones with wxCondition + wxMUTEX_RECURSIVE +}; + +// forward declarations +class WXDLLIMPEXP_FWD_BASE wxThreadHelper; +class WXDLLIMPEXP_FWD_BASE wxConditionInternal; +class WXDLLIMPEXP_FWD_BASE wxMutexInternal; +class WXDLLIMPEXP_FWD_BASE wxSemaphoreInternal; +class WXDLLIMPEXP_FWD_BASE wxThreadInternal; + // ---------------------------------------------------------------------------- // A mutex object is a synchronization object whose state is set to signaled // when it is not owned by any thread, and nonsignaled when it is owned. Its @@ -80,46 +135,62 @@ enum // you should consider wxMutexLocker whenever possible instead of directly // working with wxMutex class - it is safer -class WXDLLEXPORT wxMutexInternal; -class WXDLLEXPORT wxMutex +class WXDLLIMPEXP_BASE wxMutex { public: // constructor & destructor - wxMutex(); + // ------------------------ + + // create either default (always safe) or recursive mutex + wxMutex(wxMutexType mutexType = wxMUTEX_DEFAULT); + + // destroys the mutex kernel object ~wxMutex(); - // Lock the mutex. + // test if the mutex has been created successfully + bool IsOk() const; + + // mutex operations + // ---------------- + + // Lock the mutex, blocking on it until it is unlocked by the other thread. + // The result of locking a mutex already locked by the current thread + // depend on the mutex type. + // + // The caller must call Unlock() later if Lock() returned wxMUTEX_NO_ERROR. wxMutexError Lock(); - // Try to lock the mutex: if it can't, returns immediately with an error. + + // Same as Lock() but return wxMUTEX_TIMEOUT if the mutex can't be locked + // during the given number of milliseconds + wxMutexError LockTimeout(unsigned long ms); + + // Try to lock the mutex: if it is currently locked, return immediately + // with an error. Otherwise the caller must call Unlock(). wxMutexError TryLock(); - // Unlock the mutex. - wxMutexError Unlock(); - // Returns true if the mutex is locked. - bool IsLocked() const { return (m_locked > 0); } + // Unlock the mutex. It is an error to unlock an already unlocked mutex + wxMutexError Unlock(); protected: - friend class wxCondition; + wxMutexInternal *m_internal; - // no assignment operator nor copy ctor - wxMutex(const wxMutex&); - wxMutex& operator=(const wxMutex&); + friend class wxConditionInternal; - int m_locked; - wxMutexInternal *m_internal; + wxDECLARE_NO_COPY_CLASS(wxMutex); }; // a helper class which locks the mutex in the ctor and unlocks it in the dtor: // this ensures that mutex is always unlocked, even if the function returns or // throws an exception before it reaches the end -class WXDLLEXPORT wxMutexLocker +class WXDLLIMPEXP_BASE wxMutexLocker { public: // lock the mutex in the ctor - wxMutexLocker(wxMutex& mutex) : m_mutex(mutex) - { m_isOk = m_mutex.Lock() == wxMUTEX_NO_ERROR; } + wxMutexLocker(wxMutex& mutex) + : m_isOk(false), m_mutex(mutex) + { m_isOk = ( m_mutex.Lock() == wxMUTEX_NO_ERROR ); } - // returns TRUE if mutex was successfully locked in ctor + // returns true if mutex was successfully locked in ctor bool IsOk() const { return m_isOk; } @@ -146,103 +217,218 @@ private: // which makes it possible to have static globals of this class // ---------------------------------------------------------------------------- -class WXDLLEXPORT wxCriticalSectionInternal; - // in order to avoid any overhead under platforms where critical sections are // just mutexes make all wxCriticalSection class functions inline -#if !defined(__WXMSW__) && !defined(__WXPM__) - #define WXCRITICAL_INLINE inline - +#if !defined(__WINDOWS__) #define wxCRITSECT_IS_MUTEX 1 -#else // MSW || OS2 - #define WXCRITICAL_INLINE + #define wxCRITSECT_INLINE WXEXPORT inline +#else // MSW #define wxCRITSECT_IS_MUTEX 0 + + #define wxCRITSECT_INLINE #endif // MSW/!MSW +enum wxCriticalSectionType +{ + // recursive critical section + wxCRITSEC_DEFAULT, + + // non-recursive critical section + wxCRITSEC_NON_RECURSIVE +}; + // you should consider wxCriticalSectionLocker whenever possible instead of // directly working with wxCriticalSection class - it is safer -class WXDLLEXPORT wxCriticalSection +class WXDLLIMPEXP_BASE wxCriticalSection { public: // ctor & dtor - WXCRITICAL_INLINE wxCriticalSection(); - WXCRITICAL_INLINE ~wxCriticalSection(); - + wxCRITSECT_INLINE wxCriticalSection( wxCriticalSectionType critSecType = wxCRITSEC_DEFAULT ); + wxCRITSECT_INLINE ~wxCriticalSection(); // enter the section (the same as locking a mutex) - WXCRITICAL_INLINE void Enter(); + wxCRITSECT_INLINE void Enter(); + + // try to enter the section (the same as trying to lock a mutex) + wxCRITSECT_INLINE bool TryEnter(); + // leave the critical section (same as unlocking a mutex) - WXCRITICAL_INLINE void Leave(); + wxCRITSECT_INLINE void Leave(); private: - // no assignment operator nor copy ctor - wxCriticalSection(const wxCriticalSection&); - wxCriticalSection& operator=(const wxCriticalSection&); - #if wxCRITSECT_IS_MUTEX wxMutex m_mutex; -#elif defined(__WXMSW__) +#elif defined(__WINDOWS__) // we can't allocate any memory in the ctor, so use placement new - // unfortunately, we have to hardcode the sizeof() here because we can't - // include windows.h from this public header - char m_buffer[24]; -#elif !defined(__WXPM__) - wxCriticalSectionInternal *m_critsect; -#else - // nothing for OS/2 -#endif // !Unix/Unix + // include windows.h from this public header and we also have to use the + // union to force the correct (i.e. maximal) alignment + // + // if CRITICAL_SECTION size changes in Windows, you'll get an assert from + // thread.cpp and will need to increase the buffer size +#ifdef __WIN64__ + typedef char wxCritSectBuffer[40]; +#else // __WIN32__ + typedef char wxCritSectBuffer[24]; +#endif + union + { + unsigned long m_dummy1; + void *m_dummy2; + + wxCritSectBuffer m_buffer; + }; +#endif // Unix&OS2/Win32 + + wxDECLARE_NO_COPY_CLASS(wxCriticalSection); }; -// keep your preprocessor name space clean -#undef WXCRITICAL_INLINE +#if wxCRITSECT_IS_MUTEX + // implement wxCriticalSection using mutexes + inline wxCriticalSection::wxCriticalSection( wxCriticalSectionType critSecType ) + : m_mutex( critSecType == wxCRITSEC_DEFAULT ? wxMUTEX_RECURSIVE : wxMUTEX_DEFAULT ) { } + inline wxCriticalSection::~wxCriticalSection() { } + + inline void wxCriticalSection::Enter() { (void)m_mutex.Lock(); } + inline bool wxCriticalSection::TryEnter() { return m_mutex.TryLock() == wxMUTEX_NO_ERROR; } + inline void wxCriticalSection::Leave() { (void)m_mutex.Unlock(); } +#endif // wxCRITSECT_IS_MUTEX + +#undef wxCRITSECT_INLINE +#undef wxCRITSECT_IS_MUTEX // wxCriticalSectionLocker is the same to critical sections as wxMutexLocker is -// to th mutexes -class WXDLLEXPORT wxCriticalSectionLocker +// to mutexes +class WXDLLIMPEXP_BASE wxCriticalSectionLocker { public: - inline wxCriticalSectionLocker(wxCriticalSection& critsect); - inline ~wxCriticalSectionLocker(); + wxCriticalSectionLocker(wxCriticalSection& cs) + : m_critsect(cs) + { + m_critsect.Enter(); + } -private: - // no assignment operator nor copy ctor - wxCriticalSectionLocker(const wxCriticalSectionLocker&); - wxCriticalSectionLocker& operator=(const wxCriticalSectionLocker&); + ~wxCriticalSectionLocker() + { + m_critsect.Leave(); + } +private: wxCriticalSection& m_critsect; + + wxDECLARE_NO_COPY_CLASS(wxCriticalSectionLocker); }; // ---------------------------------------------------------------------------- -// Condition variable: allows to block the thread execution until something -// happens (== condition is signaled) +// wxCondition models a POSIX condition variable which allows one (or more) +// thread(s) to wait until some condition is fulfilled // ---------------------------------------------------------------------------- -class wxConditionInternal; -class WXDLLEXPORT wxCondition +class WXDLLIMPEXP_BASE wxCondition { public: - // constructor & destructor - wxCondition(); + // Each wxCondition object is associated with a (single) wxMutex object. + // The mutex object MUST be locked before calling Wait() + wxCondition(wxMutex& mutex); + + // dtor is not virtual, don't use this class polymorphically ~wxCondition(); - // wait until the condition is signaled - // waits indefinitely. - void Wait(); - // waits until a signal is raised or the timeout elapses - bool Wait(unsigned long sec, unsigned long nsec); + // return true if the condition has been created successfully + bool IsOk() const; + + // NB: the associated mutex MUST be locked beforehand by the calling thread + // + // it atomically releases the lock on the associated mutex + // and starts waiting to be woken up by a Signal()/Broadcast() + // once its signaled, then it will wait until it can reacquire + // the lock on the associated mutex object, before returning. + wxCondError Wait(); + + // exactly as Wait() except that it may also return if the specified + // timeout elapses even if the condition hasn't been signalled: in this + // case, the return value is false, otherwise (i.e. in case of a normal + // return) it is true + // + // the timeout parameter specifies an interval that needs to be waited for + // in milliseconds + wxCondError WaitTimeout(unsigned long milliseconds); + + // NB: the associated mutex may or may not be locked by the calling thread + // + // this method unblocks one thread if any are blocking on the condition. + // if no thread is blocking in Wait(), then the signal is NOT remembered + // The thread which was blocking on Wait() will then reacquire the lock + // on the associated mutex object before returning + wxCondError Signal(); + + // NB: the associated mutex may or may not be locked by the calling thread + // + // this method unblocks all threads if any are blocking on the condition. + // if no thread is blocking in Wait(), then the signal is NOT remembered + // The threads which were blocking on Wait() will then reacquire the lock + // on the associated mutex object before returning. + wxCondError Broadcast(); + - // signal the condition - // wakes up one (and only one) of the waiting threads - void Signal(); - // wakes up all threads waiting onthis condition - void Broadcast(); +#if WXWIN_COMPATIBILITY_2_6 + // deprecated version, don't use + wxDEPRECATED( bool Wait(unsigned long milliseconds) ); +#endif // WXWIN_COMPATIBILITY_2_6 private: wxConditionInternal *m_internal; + + wxDECLARE_NO_COPY_CLASS(wxCondition); }; +#if WXWIN_COMPATIBILITY_2_6 + inline bool wxCondition::Wait(unsigned long milliseconds) + { return WaitTimeout(milliseconds) == wxCOND_NO_ERROR; } +#endif // WXWIN_COMPATIBILITY_2_6 + // ---------------------------------------------------------------------------- -// Thread class +// wxSemaphore: a counter limiting the number of threads concurrently accessing +// a shared resource +// ---------------------------------------------------------------------------- + +class WXDLLIMPEXP_BASE wxSemaphore +{ +public: + // specifying a maxcount of 0 actually makes wxSemaphore behave as if there + // is no upper limit, if maxcount is 1 the semaphore behaves as a mutex + wxSemaphore( int initialcount = 0, int maxcount = 0 ); + + // dtor is not virtual, don't use this class polymorphically + ~wxSemaphore(); + + // return true if the semaphore has been created successfully + bool IsOk() const; + + // wait indefinitely, until the semaphore count goes beyond 0 + // and then decrement it and return (this method might have been called + // Acquire()) + wxSemaError Wait(); + + // same as Wait(), but does not block, returns wxSEMA_NO_ERROR if + // successful and wxSEMA_BUSY if the count is currently zero + wxSemaError TryWait(); + + // same as Wait(), but as a timeout limit, returns wxSEMA_NO_ERROR if the + // semaphore was acquired and wxSEMA_TIMEOUT if the timeout has elapsed + wxSemaError WaitTimeout(unsigned long milliseconds); + + // increments the semaphore count and signals one of the waiting threads + wxSemaError Post(); + +private: + wxSemaphoreInternal *m_internal; + + wxDECLARE_NO_COPY_CLASS(wxSemaphore); +}; + +// ---------------------------------------------------------------------------- +// wxThread: class encapsulating a thread of execution // ---------------------------------------------------------------------------- // there are two different kinds of threads: joinable and detached (default) @@ -254,8 +440,14 @@ private: // 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 +// On VMS thread pointers are 64 bits (also needed for other systems??? +#ifdef __VMS + typedef unsigned long long wxThreadIdType; +#else + typedef unsigned long wxThreadIdType; +#endif + +class WXDLLIMPEXP_BASE wxThread { public: // the return type for the thread function @@ -270,14 +462,24 @@ public: 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 + // + // Notice that it also returns true if main thread id hadn't been + // initialized yet on the assumption that it's too early in wx startup + // process for any other threads to have been created in this case. + static bool IsMain() + { + return !ms_idMainThread || GetCurrentId() == ms_idMainThread; + } + + // Return the main thread id + static wxThreadIdType GetMainId() { return ms_idMainThread; } + + // 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()! + // This is the same as wxMilliSleep(). static void Sleep(unsigned long milliseconds); // get the number of system CPUs - useful with SetConcurrency() @@ -286,12 +488,17 @@ public: // 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 + // Returns true on success, false otherwise (if not implemented, for // example) static bool SetConcurrency(size_t level); @@ -303,8 +510,11 @@ public: // from _another_ thread (typically the thread that created this one, e.g. // the main thread), not from the thread itself - // create a new thread - call Run() to start it - wxThreadError Create(); + // 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 @@ -321,18 +531,19 @@ public: // does it! // // will fill the rc pointer with the thread exit code if it's !NULL - wxThreadError Delete(ExitCode *rc = (ExitCode *)NULL); + wxThreadError Delete(ExitCode *rc = NULL, + wxThreadWait waitMode = wxTHREAD_WAIT_DEFAULT); // 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(); + ExitCode Wait(wxThreadWait waitMode = wxTHREAD_WAIT_DEFAULT); // 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! + // 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 @@ -347,7 +558,8 @@ public: wxThreadError Resume(); // priority - // Sets the priority to "prio": see WXTHREAD_XXX_PRIORITY constants + // Sets the priority to "prio" which must be in 0..100 range (see + // also wxPRIORITY_XXX constants). // // NB: the priority can only be set before the thread is created void SetPriority(unsigned int prio); @@ -368,27 +580,21 @@ public: // Get the thread ID - a platform dependent number which uniquely // identifies a thread inside a process -#ifdef __VMS - unsigned long long GetId() const; -#else - unsigned long GetId() const; -#endif - - // 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() { } + wxThreadIdType GetId() const; + + wxThreadKind GetKind() const + { return m_isDetached ? wxTHREAD_DETACHED : wxTHREAD_JOINABLE; } + + // 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: - // 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(); - // exits from the current thread - can be called only from this thread void Exit(ExitCode exitcode = 0); @@ -396,12 +602,35 @@ protected: // of this thread. virtual void *Entry() = 0; + + // Callbacks which may be overridden by the derived class to perform some + // specific actions when the thread is deleted or killed. By default they + // do nothing. + + // This one is called by Delete() before actually deleting the thread and + // is executed in the context of the thread that called Delete(). + virtual void OnDelete() {} + + // This one is called by Kill() before killing the thread and is executed + // in the context of the thread that called Kill(). + virtual void OnKill() {} + private: // no copy ctor/assignment operator wxThread(const wxThread&); wxThread& operator=(const wxThread&); + // 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() { } + friend class wxThreadInternal; + friend class wxThreadModule; + + + // the main thread identifier, should be set on startup + static wxThreadIdType ms_idMainThread; // the (platform-dependent) thread class implementation wxThreadInternal *m_internal; @@ -413,40 +642,193 @@ private: 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 wxThreadHelperThread is detached and is about to finish, it will + // set m_thread to NULL so don't delete it then. + // But if KillThread is called before wxThreadHelperThread (in detached mode) + // 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(); } + +#if WXWIN_COMPATIBILITY_2_8 + wxDEPRECATED( wxThreadError Create(unsigned int stackSize = 0) ); +#endif + + // create a new thread (and optionally set the stack size on platforms that + // support/need that), call Run() to start it + wxThreadError CreateThread(wxThreadKind kind = wxTHREAD_JOINABLE, + unsigned int stackSize = 0) + { + KillThread(); + + m_kind = kind; + 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; +}; + +#if WXWIN_COMPATIBILITY_2_8 +inline wxThreadError wxThreadHelper::Create(unsigned int stackSize) +{ return CreateThread(m_kind, stackSize); } +#endif + +// 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 WXDLLEXPORT wxMutexGuiEnter(); -void WXDLLEXPORT wxMutexGuiLeave(); +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) -#else // !wxUSE_THREADS +// 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(); } -#include "wx/defs.h" // for WXDLLEXPORT +#else // !wxUSE_THREADS // no thread support -inline void WXDLLEXPORT wxMutexGuiEnter() { } -inline void WXDLLEXPORT wxMutexGuiLeave() { } +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" -#define wxENTER_CRIT_SECT(cs) -#define wxLEAVE_CRIT_SECT(cs) -#define wxCRIT_SECT_DECLARE(cs) -#define wxCRIT_SECT_LOCKER(name, cs) - -#endif // wxUSE_THREADS - -// automatically unlock GUI mutex in dtor -class WXDLLEXPORT wxMutexGuiLocker +// (the implementation uses dummy structs to force semicolon after the macro; +// also notice that Watcom doesn't like declaring a struct as a member so we +// need to actually define it in wxCRIT_SECT_DECLARE_MEMBER) +#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(); } @@ -459,69 +841,25 @@ public: #if wxUSE_THREADS -#if defined(__WXMSW__) +#if defined(__WINDOWS__) || defined(__OS2__) || defined(__EMX__) || defined(__DARWIN__) // 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(); + extern void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter(); - // returns TRUE if the main thread has GUI lock - extern bool WXDLLEXPORT wxGuiOwnedByMainThread(); + // 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 WXDLLEXPORT wxWakeUpMainThread(); + extern void WXDLLIMPEXP_BASE wxWakeUpMainThread(); - // return TRUE if the main thread is waiting for some other to terminate: +#ifndef __DARWIN__ + // return true if the main thread is waiting for some other to terminate: // wxApp then should block all "dangerous" messages - extern bool WXDLLEXPORT wxIsWaitingForThread(); -#elif defined(__WXMAC__) - 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(); - - // 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(); } -#elif defined(__WXPM__) - // 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(); - - // 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 && !PM - // 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 + extern bool WXDLLIMPEXP_BASE wxIsWaitingForThread(); +#endif +#endif // MSW, OS/2 - // we can define these inline functions now (they should be defined after - // wxCriticalSection::Enter/Leave) - inline - wxCriticalSectionLocker:: wxCriticalSectionLocker(wxCriticalSection& cs) - : m_critsect(cs) { m_critsect.Enter(); } - inline - wxCriticalSectionLocker::~wxCriticalSectionLocker() { m_critsect.Leave(); } #endif // wxUSE_THREADS -#endif // __THREADH__ +#endif // _WX_THREAD_H_