X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/cb4f1ca43a115e5ee862b19304bd4c6294aac101..08e5319b03f80c8554a49c1ef4c9d2adaa8587ce:/include/wx/thread.h diff --git a/include/wx/thread.h b/include/wx/thread.h index 906a4eb517..8652d6cbf8 100644 --- a/include/wx/thread.h +++ b/include/wx/thread.h @@ -1,55 +1,125 @@ ///////////////////////////////////////////////////////////////////////////// -// Name: thread.h +// Name: wx/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 // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// -#ifndef __THREADH__ -#define __THREADH__ - -#ifdef __GNUG__ -#pragma interface "thread.h" -#endif +#ifndef _WX_THREAD_H_ +#define _WX_THREAD_H_ // ---------------------------------------------------------------------------- // headers // ---------------------------------------------------------------------------- -#include "wx/setup.h" + +// get the value of wxUSE_THREADS configuration flag +#include "wx/defs.h" #if wxUSE_THREADS + +// only for wxUSE_THREADS - otherwise we'd get undefined symbols +#if defined(__GNUG__) && !defined(__APPLE__) + #pragma interface "thread.h" +#endif + +// Windows headers define it +#ifdef Yield + #undef Yield +#endif + #include "wx/module.h" // ---------------------------------------------------------------------------- // constants // ---------------------------------------------------------------------------- -typedef enum +enum wxMutexError +{ + 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_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 +{ + wxTHREAD_NO_ERROR = 0, // No error + wxTHREAD_NO_RESOURCE, // No resource left to create a new thread + wxTHREAD_RUNNING, // The thread is already running + wxTHREAD_NOT_RUNNING, // The thread isn't running + wxTHREAD_KILLED, // Thread we waited for had to be killed + wxTHREAD_MISC_ERROR // Some other error +}; + +enum wxThreadKind +{ + wxTHREAD_DETACHED, + wxTHREAD_JOINABLE +}; + +// defines the interval of priority +enum { - 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 -} wxMutexError; - -typedef enum + WXTHREAD_MIN_PRIORITY = 0u, + WXTHREAD_DEFAULT_PRIORITY = 50u, + WXTHREAD_MAX_PRIORITY = 100u +}; + +// 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 { - wxTHREAD_NO_ERROR = 0, // No error - wxTHREAD_NO_RESOURCE, // No resource left to create a new thread - wxTHREAD_RUNNING, // The thread is already running - wxTHREAD_NOT_RUNNING, // The thread isn't running - 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 + // normal mutex: try to always use this one + wxMUTEX_DEFAULT, + + // recursive mutex: don't use these ones with wxCondition + wxMUTEX_RECURSIVE +}; + +// forward declarations +class WXDLLEXPORT wxConditionInternal; +class WXDLLEXPORT wxMutexInternal; +class WXDLLEXPORT wxSemaphoreInternal; +class WXDLLEXPORT wxThreadInternal; // ---------------------------------------------------------------------------- // A mutex object is a synchronization object whose state is set to signaled @@ -60,33 +130,44 @@ 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(); + // constructor & destructor + // ------------------------ + + // 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. + + // 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 *p_internal; + DECLARE_NO_COPY_CLASS(wxMutex) }; // a helper class which locks the mutex in the ctor and unlocks it in the dtor: @@ -96,14 +177,17 @@ 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_isOk(FALSE), 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 @@ -111,154 +195,392 @@ private: wxMutexLocker& operator=(const wxMutexLocker&); bool m_isOk; - wxMutex *m_mutex; + wxMutex& m_mutex; }; -#ifdef __WXMSW__ - // ---------------------------------------------------------------------------- // Critical section: this is the same as mutex but is only visible to the // threads of the same process. For the platforms which don't have native // support for critical sections, they're implemented entirely in terms of -// mutexes +// mutexes. +// +// NB: wxCriticalSection object does not allocate any memory in its ctor +// which makes it possible to have static globals of this class // ---------------------------------------------------------------------------- +// 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 wxCRITSECT_IS_MUTEX 1 + + #define wxCRITSECT_INLINE inline +#else // MSW || OS2 + #define wxCRITSECT_IS_MUTEX 0 + + #define wxCRITSECT_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(); + wxCRITSECT_INLINE wxCriticalSection(); + wxCRITSECT_INLINE ~wxCriticalSection(); // enter the section (the same as locking a mutex) - void Enter(); + wxCRITSECT_INLINE void Enter(); + // leave the critical section (same as unlocking a mutex) - void Leave(); + wxCRITSECT_INLINE void Leave(); private: - // no assignment operator nor copy ctor - wxCriticalSection(const wxCriticalSection&); - wxCriticalSection& operator=(const wxCriticalSection&); - - wxCriticalSectionInternal *m_critsect; +#if wxCRITSECT_IS_MUTEX + wxMutex m_mutex; +#elif defined(__WXMSW__) + // 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 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 + // + // finally, we need this typedef instead of declaring m_buffer directly + // because otherwise the assert mentioned above wouldn't compile with some + // compilers (notably CodeWarrior 8) + typedef char wxCritSectBuffer[24]; + union + { + unsigned long m_dummy1; + void *m_dummy2; + + wxCritSectBuffer m_buffer; + }; +#else + // nothing for OS/2 +#endif // Unix/Win32/OS2 + + DECLARE_NO_COPY_CLASS(wxCriticalSection) }; +#if wxCRITSECT_IS_MUTEX + // 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 // 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 { public: - wxCriticalSectionLocker(wxCriticalSection& critsect) : m_critsect(critsect) - { m_critsect.Enter(); } + wxCriticalSectionLocker(wxCriticalSection& cs) + : m_critsect(cs) + { + m_critsect.Enter(); + } + ~wxCriticalSectionLocker() - { m_critsect.Leave(); } + { + m_critsect.Leave(); + } private: - // no assignment operator nor copy ctor - wxCriticalSectionLocker(const wxCriticalSectionLocker&); - wxCriticalSectionLocker& operator=(const wxCriticalSectionLocker&); - wxCriticalSection& m_critsect; -}; -#endif + DECLARE_NO_COPY_CLASS(wxCriticalSectionLocker) +}; // ---------------------------------------------------------------------------- -// Condition handler. +// 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 WXDLLEXPORT wxCondition { public: - // constructor & destructor - wxCondition(); - ~wxCondition(); - - // Waits indefinitely. - void Wait(wxMutex& mutex); - // Waits until a signal is raised or the timeout is elapsed. - bool Wait(wxMutex& mutex, unsigned long sec, unsigned long nsec); - // Raises a signal: only one "Waiter" is released. - void Signal(); - // Broadcasts to all "Waiters". - void Broadcast(); + // 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(); + + // 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 ellapses 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 timeeout parameter specifies a interval that needs to be waited 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(); + + + // deprecated version, don't use + bool Wait(unsigned long milliseconds) + { return WaitTimeout(milliseconds) == wxCOND_NO_ERROR; } private: - wxConditionInternal *p_internal; + wxConditionInternal *m_internal; + + DECLARE_NO_COPY_CLASS(wxCondition) }; // ---------------------------------------------------------------------------- -// Thread management class +// wxSemaphore: a counter limiting the number of threads concurrently accessing +// a shared resource // ---------------------------------------------------------------------------- -class wxThreadInternal; -class WXDLLEXPORT wxThread +class WXDLLEXPORT wxSemaphore { public: - // constructor & destructor. - wxThread(); - virtual ~wxThread(); + // 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 ); - // Create a new thread, this method should check there is only one thread - // running by object. - wxThreadError Create(); + // dtor is not virtual, don't use this class polymorphically + ~wxSemaphore(); - // Destroys the thread immediately if the defer flag isn't true. - wxThreadError Destroy(); + // return TRUE if the semaphore has been created successfully + bool IsOk() const; - // Pause a running thread - wxThreadError Pause(); + // wait indefinitely, until the semaphore count goes beyond 0 + // and then decrement it and return (this method might have been called + // Acquire()) + wxSemaError Wait(); - // Resume a paused thread - wxThreadError Resume(); + // same as Wait(), but does not block, returns wxSEMA_NO_ERROR if + // successful and wxSEMA_BUSY if the count is currently zero + wxSemaError TryWait(); - // Switches on the defer flag. - void DeferDestroy(bool on); + // same as Wait(), but as a timeout limit, returns wxSEMA_NO_ERROR if the + // semaphore was acquired and wxSEMA_TIMEOUT if the timeout has ellapsed + wxSemaError WaitTimeout(unsigned long milliseconds); - // Waits for the termination of the thread. - void *Join(); + // increments the semaphore count and signals one of the waiting threads + wxSemaError Post(); - // 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; +private: + wxSemaphoreInternal *m_internal; - // Get the thread ID - unsigned long GetID() const; + DECLARE_NO_COPY_CLASS(wxSemaphore) +}; - // 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(); } +// ---------------------------------------------------------------------------- +// wxThread: class encpasulating a thread of execution +// ---------------------------------------------------------------------------- + +// there are two different kinds of threads: joinable and detached (default) +// ones. Only joinable threads can return a return code and only detached +// threads auto-delete themselves - the user should delete the joinable +// threads manually. + +// 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) - // Returns true if current thread is the main thread (aka the GUI thread) - static bool IsMain(); +// 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 - // Called when thread exits. - virtual void OnExit(); +class WXDLLEXPORT 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 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); + + // 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 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 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() { } + + // 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 - bool TestDestroy(); + // 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. - void Exit(void *status = NULL); + // exits from the current thread - can be called only from this thread + void Exit(ExitCode exitcode = 0); -private: - // Entry point for the thread. - virtual void *Entry() = 0; + // entry point for the thread - called by Run() and executes in the context + // of this thread. + virtual void *Entry() = 0; private: - friend class wxThreadInternal; + // no copy ctor/assignment operator + wxThread(const wxThread&); + wxThread& operator=(const wxThread&); + + friend class wxThreadInternal; + + // the (platform-dependent) thread class implementation + wxThreadInternal *m_internal; - wxThreadInternal *p_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; }; // ---------------------------------------------------------------------------- @@ -269,19 +591,12 @@ private: void WXDLLEXPORT wxMutexGuiEnter(); void WXDLLEXPORT wxMutexGuiLeave(); -// implementation only -#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 - void WXDLLEXPORT wxMutexGuiLeaveOrEnter(); - - // returns TRUE if the main thread has GUI lock - inline bool WXDLLEXPORT wxGuiOwnedByMainThread(); - - // wakes up the main thread if it's sleeping inside ::GetMessage() - inline void WXDLLEXPORT wxWakeUpMainThread(); -#endif // MSW +// 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_LOCKER(name, cs) wxCriticalSectionLocker name(cs) #else // !wxUSE_THREADS @@ -289,9 +604,37 @@ void WXDLLEXPORT wxMutexGuiLeave(); inline void WXDLLEXPORT wxMutexGuiEnter() { } inline void WXDLLEXPORT wxMutexGuiLeave() { } -#endif // wxUSE_THREADS - -// automatically unlock GUI mutex in dtor +// 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/!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 WXDLLEXPORT wxMutexGuiLocker { public: @@ -299,4 +642,32 @@ public: ~wxMutexGuiLocker() { wxMutexGuiLeave(); } }; -#endif // __THREADH__ +// ----------------------------------------------------------------------------- +// implementation only until the end of file +// ----------------------------------------------------------------------------- + +#if wxUSE_THREADS + +#if defined(__WXMSW__) || defined(__WXMAC__) || 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(); + +#ifndef __WXPM__ + // wakes up the main thread if it's sleeping inside ::GetMessage() + extern void WXDLLEXPORT wxWakeUpMainThread(); +#endif // !OS/2 + + // return TRUE if the main thread is waiting for some other to terminate: + // wxApp then should block all "dangerous" messages + extern bool WXDLLEXPORT wxIsWaitingForThread(); +#endif // MSW, Mac, OS/2 + +#endif // wxUSE_THREADS + +#endif // _WX_THREAD_H_ +