X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/be8098689121d2352751c51005c133797d77ecea..dd9f8b6bb6935360a8271dc3e8749fb026b601a8:/src/msw/thread.cpp diff --git a/src/msw/thread.cpp b/src/msw/thread.cpp index ec70911da4..942a0379da 100644 --- a/src/msw/thread.cpp +++ b/src/msw/thread.cpp @@ -1,19 +1,15 @@ ///////////////////////////////////////////////////////////////////////////// -// Name: thread.cpp +// Name: src/msw/thread.cpp // Purpose: wxThread Implementation // Author: Original from Wolfram Gloger/Guilhem Lavaux // Modified by: Vadim Zeitlin to make it work :-) // Created: 04/22/98 // RCS-ID: $Id$ -// Copyright: (c) Wolfram Gloger (1996, 1997); Guilhem Lavaux (1998), -// Vadim Zeitlin (1999) +// Copyright: (c) Wolfram Gloger (1996, 1997), Guilhem Lavaux (1998); +// Vadim Zeitlin (1999-2002) // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// -#ifdef __GNUG__ - #pragma implementation "thread.h" -#endif - // ---------------------------------------------------------------------------- // headers // ---------------------------------------------------------------------------- @@ -25,20 +21,24 @@ #pragma hdrstop #endif +#if wxUSE_THREADS + +#include "wx/thread.h" + #ifndef WX_PRECOMP -# include "wx/wx.h" + #include "wx/intl.h" + #include "wx/app.h" + #include "wx/module.h" #endif -#if wxUSE_THREADS +#include "wx/apptrait.h" +#include "wx/scopeguard.h" #include "wx/msw/private.h" +#include "wx/msw/missing.h" +#include "wx/msw/seh.h" -#include "wx/module.h" -#include "wx/thread.h" - -#ifdef Yield -# undef Yield -#endif +#include "wx/except.h" // must have this symbol defined to get _beginthread/_endthread declarations #ifndef _MT @@ -62,18 +62,21 @@ #if defined(__VISUALC__) || \ (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \ (defined(__GNUG__) && defined(__MSVCRT__)) || \ - defined(__WATCOMC__) + defined(__WATCOMC__) || defined(__MWERKS__) +#ifndef __WXWINCE__ #undef wxUSE_BEGIN_THREAD #define wxUSE_BEGIN_THREAD #endif +#endif + #ifdef wxUSE_BEGIN_THREAD // this is where _beginthreadex() is declared #include // the return type of the thread function entry point - typedef unsigned THREAD_RETVAL; + typedef wxUIntPtr THREAD_RETVAL; // the calling convention of the thread function entry point #define THREAD_CALLCONV __stdcall @@ -83,6 +86,8 @@ #define THREAD_CALLCONV WINAPI #endif +static const THREAD_RETVAL THREAD_ERROR_EXIT = (THREAD_RETVAL)-1; + // ---------------------------------------------------------------------------- // constants // ---------------------------------------------------------------------------- @@ -109,8 +114,8 @@ static DWORD gs_tlsThisThread = 0xFFFFFFFF; // calling wxMutexGuiEnter() static DWORD gs_idMainThread = 0; -// if it's FALSE, some secondary thread is holding the GUI lock -static bool gs_bGuiOwnedByMainThread = TRUE; +// if it's false, some secondary thread is holding the GUI lock +static bool gs_bGuiOwnedByMainThread = true; // critical section which controls access to all GUI functions: any secondary // thread (i.e. except the main one) must enter this crit section before doing @@ -120,448 +125,263 @@ static wxCriticalSection *gs_critsectGui = NULL; // critical section which protects gs_nWaitingForGui variable static wxCriticalSection *gs_critsectWaitingForGui = NULL; +// critical section which serializes WinThreadStart() and WaitForTerminate() +// (this is a potential bottleneck, we use a single crit sect for all threads +// in the system, but normally time spent inside it should be quite short) +static wxCriticalSection *gs_critsectThreadDelete = NULL; + // number of threads waiting for GUI in wxMutexGuiEnter() static size_t gs_nWaitingForGui = 0; // are we waiting for a thread termination? -static bool gs_waitingForThread = FALSE; +static bool gs_waitingForThread = false; // ============================================================================ -// Windows implementation of thread classes +// Windows implementation of thread and related classes // ============================================================================ // ---------------------------------------------------------------------------- -// wxMutex implementation +// wxCriticalSection // ---------------------------------------------------------------------------- -class wxMutexInternal -{ -public: - wxMutexInternal() - { - m_mutex = ::CreateMutex(NULL, FALSE, NULL); - if ( !m_mutex ) - { - wxLogSysError(_("Can not create mutex")); - } - } - - ~wxMutexInternal() { if ( m_mutex ) ::CloseHandle(m_mutex); } - -public: - HANDLE m_mutex; -}; - -wxMutex::wxMutex() -{ - m_internal = new wxMutexInternal; - - m_locked = 0; -} - -wxMutex::~wxMutex() +wxCriticalSection::wxCriticalSection() { - if ( m_locked > 0 ) - { - wxLogDebug(_T("Warning: freeing a locked mutex (%d locks)."), m_locked); - } + wxCOMPILE_TIME_ASSERT( sizeof(CRITICAL_SECTION) <= sizeof(wxCritSectBuffer), + wxCriticalSectionBufferTooSmall ); - delete m_internal; + ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer); } -wxMutexError wxMutex::Lock() +wxCriticalSection::~wxCriticalSection() { - DWORD ret; - - ret = WaitForSingleObject(m_internal->m_mutex, INFINITE); - switch ( ret ) - { - case WAIT_ABANDONED: - return wxMUTEX_BUSY; - - case WAIT_OBJECT_0: - // ok - break; - - case WAIT_FAILED: - wxLogSysError(_("Couldn't acquire a mutex lock")); - return wxMUTEX_MISC_ERROR; - - case WAIT_TIMEOUT: - default: - wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock")); - } - - m_locked++; - return wxMUTEX_NO_ERROR; + ::DeleteCriticalSection((CRITICAL_SECTION *)m_buffer); } -wxMutexError wxMutex::TryLock() +void wxCriticalSection::Enter() { - DWORD ret; - - ret = WaitForSingleObject(m_internal->m_mutex, 0); - if (ret == WAIT_TIMEOUT || ret == WAIT_ABANDONED) - return wxMUTEX_BUSY; - - m_locked++; - return wxMUTEX_NO_ERROR; + ::EnterCriticalSection((CRITICAL_SECTION *)m_buffer); } -wxMutexError wxMutex::Unlock() +void wxCriticalSection::Leave() { - if (m_locked > 0) - m_locked--; - - BOOL ret = ReleaseMutex(m_internal->m_mutex); - if ( ret == 0 ) - { - wxLogSysError(_("Couldn't release a mutex")); - return wxMUTEX_MISC_ERROR; - } - - return wxMUTEX_NO_ERROR; + ::LeaveCriticalSection((CRITICAL_SECTION *)m_buffer); } -// ========================================================================== -// wxSemaphore -// ========================================================================== - -// -------------------------------------------------------------------------- -// wxSemaphoreInternal -// -------------------------------------------------------------------------- +// ---------------------------------------------------------------------------- +// wxMutex +// ---------------------------------------------------------------------------- -class wxSemaphoreInternal +class wxMutexInternal { public: - wxSemaphoreInternal( int initialcount = 0, int maxcount = 0 ); - ~wxSemaphoreInternal(); - - void Wait(); - bool TryWait(); + wxMutexInternal(wxMutexType mutexType); + ~wxMutexInternal(); - bool Wait( unsigned long timeout_millis ); + bool IsOk() const { return m_mutex != NULL; } - void Post(); + wxMutexError Lock() { return LockTimeout(INFINITE); } + wxMutexError Lock(unsigned long ms) { return LockTimeout(ms); } + wxMutexError TryLock(); + wxMutexError Unlock(); private: - HANDLE m_semaphore; + wxMutexError LockTimeout(DWORD milliseconds); + + HANDLE m_mutex; + + DECLARE_NO_COPY_CLASS(wxMutexInternal) }; -wxSemaphoreInternal::wxSemaphoreInternal( int initialcount, int maxcount ) +// all mutexes are recursive under Win32 so we don't use mutexType +wxMutexInternal::wxMutexInternal(wxMutexType WXUNUSED(mutexType)) { - if ( maxcount == 0 ) - { - // make it practically infinite - maxcount = INT_MAX; - } + // create a nameless (hence intra process and always private) mutex + m_mutex = ::CreateMutex + ( + NULL, // default secutiry attributes + FALSE, // not initially locked + NULL // no name + ); - m_semaphore = ::CreateSemaphore( NULL, initialcount, maxcount, NULL ); - if ( !m_semaphore ) + if ( !m_mutex ) { - wxLogLastError(_T("CreateSemaphore()")); + wxLogLastError(_T("CreateMutex()")); } } -wxSemaphoreInternal::~wxSemaphoreInternal() +wxMutexInternal::~wxMutexInternal() { - CloseHandle( m_semaphore ); -} - -void wxSemaphoreInternal::Wait() -{ - if ( ::WaitForSingleObject( m_semaphore, INFINITE ) != WAIT_OBJECT_0 ) + if ( m_mutex ) { - wxLogLastError(_T("WaitForSingleObject")); + if ( !::CloseHandle(m_mutex) ) + { + wxLogLastError(_T("CloseHandle(mutex)")); + } } } -bool wxSemaphoreInternal::TryWait() +wxMutexError wxMutexInternal::TryLock() { - return Wait(0); + const wxMutexError rc = LockTimeout(0); + + // we have a special return code for timeout in this case + return rc == wxMUTEX_TIMEOUT ? wxMUTEX_BUSY : rc; } -bool wxSemaphoreInternal::Wait( unsigned long timeout_millis ) +wxMutexError wxMutexInternal::LockTimeout(DWORD milliseconds) { - DWORD result = ::WaitForSingleObject( m_semaphore, timeout_millis ); + DWORD rc = ::WaitForSingleObject(m_mutex, milliseconds); + if ( rc == WAIT_ABANDONED ) + { + // the previous caller died without releasing the mutex, but now we can + // really lock it + wxLogDebug(_T("WaitForSingleObject() returned WAIT_ABANDONED")); + + // use 0 timeout, normally we should always get it + rc = ::WaitForSingleObject(m_mutex, 0); + } - switch ( result ) + switch ( rc ) { case WAIT_OBJECT_0: - return TRUE; + // ok + break; case WAIT_TIMEOUT: - break; + return wxMUTEX_TIMEOUT; + case WAIT_ABANDONED: // checked for above default: - wxLogLastError(_T("WaitForSingleObject()")); + wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock")); + // fall through + + case WAIT_FAILED: + wxLogLastError(_T("WaitForSingleObject(mutex)")); + return wxMUTEX_MISC_ERROR; } - return FALSE; + return wxMUTEX_NO_ERROR; } -void wxSemaphoreInternal::Post() +wxMutexError wxMutexInternal::Unlock() { - if ( !::ReleaseSemaphore( m_semaphore, 1, NULL ) ) + if ( !::ReleaseMutex(m_mutex) ) { - wxLogLastError(_T("ReleaseSemaphore")); + wxLogLastError(_T("ReleaseMutex()")); + + return wxMUTEX_MISC_ERROR; } + + return wxMUTEX_NO_ERROR; } // -------------------------------------------------------------------------- // wxSemaphore // -------------------------------------------------------------------------- -wxSemaphore::wxSemaphore( int initialcount, int maxcount ) -{ - m_internal = new wxSemaphoreInternal( initialcount, maxcount ); -} - -wxSemaphore::~wxSemaphore() -{ - delete m_internal; -} - -void wxSemaphore::Wait() -{ - m_internal->Wait(); -} - -bool wxSemaphore::TryWait() -{ - return m_internal->TryWait(); -} - -bool wxSemaphore::Wait( unsigned long timeout_millis ) -{ - return m_internal->Wait( timeout_millis ); -} - -void wxSemaphore::Post() +// a trivial wrapper around Win32 semaphore +class wxSemaphoreInternal { - m_internal->Post(); -} - - -// ========================================================================== -// wxCondition -// ========================================================================== +public: + wxSemaphoreInternal(int initialcount, int maxcount); + ~wxSemaphoreInternal(); -// -------------------------------------------------------------------------- -// wxConditionInternal -// -------------------------------------------------------------------------- + bool IsOk() const { return m_semaphore != NULL; } -class wxConditionInternal -{ -public: - wxConditionInternal( wxMutex *mutex ); - ~wxConditionInternal(); + wxSemaError Wait() { return WaitTimeout(INFINITE); } - void Wait(); + wxSemaError TryWait() + { + wxSemaError rc = WaitTimeout(0); + if ( rc == wxSEMA_TIMEOUT ) + rc = wxSEMA_BUSY; - bool Wait( unsigned long timeout_millis ); + return rc; + } - void Signal(); + wxSemaError WaitTimeout(unsigned long milliseconds); - void Broadcast(); + wxSemaError Post(); private: - int m_numWaiters; - wxMutex m_mutexNumWaiters; - - wxMutex *m_mutex; + HANDLE m_semaphore; - wxSemaphore m_semaphore; + DECLARE_NO_COPY_CLASS(wxSemaphoreInternal) }; -wxConditionInternal::wxConditionInternal( wxMutex *mutex ) +wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount) { - m_mutex = mutex; - - m_numWaiters = 0; -} - -wxConditionInternal::~wxConditionInternal() -{ -} +#if !defined(_WIN32_WCE) || (_WIN32_WCE >= 300) + if ( maxcount == 0 ) + { + // make it practically infinite + maxcount = INT_MAX; + } -void wxConditionInternal::Wait() -{ - // increment the number of waiters - m_mutexNumWaiters.Lock(); - m_numWaiters++; - m_mutexNumWaiters.Unlock(); - - m_mutex->Unlock(); - - // a potential race condition can occur here - // - // after a thread increments nwaiters, and unlocks the mutex and before the - // semaphore.Wait() is called, if another thread can cause a signal to be - // generated - // - // this race condition is handled by using a semaphore and incrementing the - // semaphore only if 'nwaiters' is greater that zero since the semaphore, - // can 'remember' signals the race condition will not occur - - // wait ( if necessary ) and decrement semaphore - m_semaphore.Wait(); - - m_mutex->Lock(); + m_semaphore = ::CreateSemaphore + ( + NULL, // default security attributes + initialcount, + maxcount, + NULL // no name + ); +#endif + if ( !m_semaphore ) + { + wxLogLastError(_T("CreateSemaphore()")); + } } -bool wxConditionInternal::Wait( unsigned long timeout_millis ) +wxSemaphoreInternal::~wxSemaphoreInternal() { - m_mutexNumWaiters.Lock(); - m_numWaiters++; - m_mutexNumWaiters.Unlock(); - - m_mutex->Unlock(); - - // a race condition can occur at this point in the code - // - // please see the comments in Wait(), for details - - bool success = TRUE; - - bool result = m_semaphore.Wait( timeout_millis ); - - if ( !result ) + if ( m_semaphore ) { - // another potential race condition exists here it is caused when a - // 'waiting' thread timesout, and returns from WaitForSingleObject, but - // has not yet decremented 'nwaiters'. - // - // at this point if another thread calls signal() then the semaphore - // will be incremented, but the waiting thread will miss it. - // - // to handle this particular case, the waiting thread calls - // WaitForSingleObject again with a timeout of 0, after locking - // 'nwaiters_mutex'. this call does not block because of the zero - // timeout, but will allow the waiting thread to catch the missed - // signals. - m_mutexNumWaiters.Lock(); - result = m_semaphore.Wait( 0 ); - - if ( !result ) + if ( !::CloseHandle(m_semaphore) ) { - m_numWaiters--; - success = FALSE; + wxLogLastError(_T("CloseHandle(semaphore)")); } - - m_mutexNumWaiters.Unlock(); } - - m_mutex->Lock(); - - return success; } -void wxConditionInternal::Signal() +wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long milliseconds) { - m_mutexNumWaiters.Lock(); + DWORD rc = ::WaitForSingleObject( m_semaphore, milliseconds ); - if ( m_numWaiters > 0 ) + switch ( rc ) { - // increment the semaphore by 1 - m_semaphore.Post(); - - m_numWaiters--; - } - - m_mutexNumWaiters.Unlock(); -} + case WAIT_OBJECT_0: + return wxSEMA_NO_ERROR; -void wxConditionInternal::Broadcast() -{ - m_mutexNumWaiters.Lock(); + case WAIT_TIMEOUT: + return wxSEMA_TIMEOUT; - while ( m_numWaiters > 0 ) - { - m_semaphore.Post(); - m_numWaiters--; + default: + wxLogLastError(_T("WaitForSingleObject(semaphore)")); } - m_mutexNumWaiters.Unlock(); + return wxSEMA_MISC_ERROR; } -// ---------------------------------------------------------------------------- -// wxCondition implementation -// ---------------------------------------------------------------------------- - -wxCondition::wxCondition( wxMutex *mutex ) +wxSemaError wxSemaphoreInternal::Post() { - if ( !mutex ) +#if !defined(_WIN32_WCE) || (_WIN32_WCE >= 300) + if ( !::ReleaseSemaphore(m_semaphore, 1, NULL /* ptr to previous count */) ) { - wxFAIL_MSG( _T("NULL mutex in wxCondition ctor") ); - - m_internal = NULL; - } - else - { - m_internal = new wxConditionInternal( mutex ); + if ( GetLastError() == ERROR_TOO_MANY_POSTS ) + { + return wxSEMA_OVERFLOW; + } + else + { + wxLogLastError(_T("ReleaseSemaphore")); + return wxSEMA_MISC_ERROR; + } } -} - -wxCondition::~wxCondition() -{ - delete m_internal; -} - -void wxCondition::Wait() -{ - if ( m_internal ) - m_internal->Wait(); -} - -bool wxCondition::Wait( unsigned long timeout_millis ) -{ - return m_internal ? m_internal->Wait(timeout_millis) : FALSE; -} - -void wxCondition::Signal() -{ - if ( m_internal ) - m_internal->Signal(); -} -void wxCondition::Broadcast() -{ - if ( m_internal ) - m_internal->Broadcast(); -} - -// ---------------------------------------------------------------------------- -// wxCriticalSection implementation -// ---------------------------------------------------------------------------- - -wxCriticalSection::wxCriticalSection() -{ -#ifdef __WXDEBUG__ - // Done this way to stop warnings during compilation about statement - // always being FALSE - int csSize = sizeof(CRITICAL_SECTION); - int bSize = sizeof(m_buffer); - wxASSERT_MSG( csSize <= bSize, - _T("must increase buffer size in wx/thread.h") ); + return wxSEMA_NO_ERROR; +#else + return wxSEMA_MISC_ERROR; #endif - - ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer); -} - -wxCriticalSection::~wxCriticalSection() -{ - ::DeleteCriticalSection((CRITICAL_SECTION *)m_buffer); -} - -void wxCriticalSection::Enter() -{ - ::EnterCriticalSection((CRITICAL_SECTION *)m_buffer); -} - -void wxCriticalSection::Leave() -{ - ::LeaveCriticalSection((CRITICAL_SECTION *)m_buffer); } // ---------------------------------------------------------------------------- @@ -574,11 +394,13 @@ void wxCriticalSection::Leave() class wxThreadInternal { public: - wxThreadInternal() + wxThreadInternal(wxThread *thread) { + m_thread = thread; m_hThread = 0; m_state = STATE_NEW; m_priority = WXTHREAD_DEFAULT_PRIORITY; + m_nRef = 1; } ~wxThreadInternal() @@ -602,6 +424,15 @@ public: // create a new (suspended) thread (for the given thread object) bool Create(wxThread *thread, unsigned int stackSize); + // wait for the thread to terminate, either by itself, or by asking it + // (politely, this is not Kill()!) to do it + wxThreadError WaitForTerminate(wxCriticalSection& cs, + wxThread::ExitCode *pRc, + wxThread *threadToDelete = NULL); + + // kill the thread unconditionally + wxThreadError Kill(); + // suspend/resume/terminate bool Suspend(); bool Resume(); @@ -619,58 +450,133 @@ public: HANDLE GetHandle() const { return m_hThread; } DWORD GetId() const { return m_tid; } - // thread function + // the thread function forwarding to DoThreadStart static THREAD_RETVAL THREAD_CALLCONV WinThreadStart(void *thread); + // really start the thread (if it's not already dead) + static THREAD_RETVAL DoThreadStart(wxThread *thread); + + // call OnExit() on the thread + static void DoThreadOnExit(wxThread *thread); + + + void KeepAlive() + { + if ( m_thread->IsDetached() ) + ::InterlockedIncrement(&m_nRef); + } + + void LetDie() + { + if ( m_thread->IsDetached() && !::InterlockedDecrement(&m_nRef) ) + delete m_thread; + } + private: + // the thread we're associated with + wxThread *m_thread; + HANDLE m_hThread; // handle of the thread wxThreadState m_state; // state, see wxThreadState enum unsigned int m_priority; // thread priority in "wx" units DWORD m_tid; // thread id + + // number of threads which need this thread to remain alive, when the count + // reaches 0 we kill the owning wxThread -- and die ourselves with it + LONG m_nRef; + + DECLARE_NO_COPY_CLASS(wxThreadInternal) }; -THREAD_RETVAL THREAD_CALLCONV wxThreadInternal::WinThreadStart(void *param) +// small class which keeps a thread alive during its lifetime +class wxThreadKeepAlive { - THREAD_RETVAL rc; - bool wasCancelled; +public: + wxThreadKeepAlive(wxThreadInternal& thrImpl) : m_thrImpl(thrImpl) + { m_thrImpl.KeepAlive(); } + ~wxThreadKeepAlive() + { m_thrImpl.LetDie(); } - // first of all, check whether we hadn't been cancelled already and don't - // start the user code at all then - wxThread *thread = (wxThread *)param; - if ( thread->m_internal->GetState() == STATE_EXITED ) +private: + wxThreadInternal& m_thrImpl; +}; + +/* static */ +void wxThreadInternal::DoThreadOnExit(wxThread *thread) +{ + wxTRY { - rc = (THREAD_RETVAL)-1; - wasCancelled = TRUE; + thread->OnExit(); } - else // do run thread + wxCATCH_ALL( wxTheApp->OnUnhandledException(); ) +} + +/* static */ +THREAD_RETVAL wxThreadInternal::DoThreadStart(wxThread *thread) +{ + wxON_BLOCK_EXIT1(DoThreadOnExit, thread); + + THREAD_RETVAL rc = THREAD_ERROR_EXIT; + + wxTRY { // store the thread object in the TLS if ( !::TlsSetValue(gs_tlsThisThread, thread) ) { wxLogSysError(_("Can not start thread: error writing TLS.")); - return (DWORD)-1; + return THREAD_ERROR_EXIT; } rc = (THREAD_RETVAL)thread->Entry(); + } + wxCATCH_ALL( wxTheApp->OnUnhandledException(); ) + + return rc; +} +/* static */ +THREAD_RETVAL THREAD_CALLCONV wxThreadInternal::WinThreadStart(void *param) +{ + THREAD_RETVAL rc = THREAD_ERROR_EXIT; + + wxThread * const thread = (wxThread *)param; + + // each thread has its own SEH translator so install our own a.s.a.p. + DisableAutomaticSETranslator(); + + // first of all, check whether we hadn't been cancelled already and don't + // start the user code at all then + const bool hasExited = thread->m_internal->GetState() == STATE_EXITED; + + // run the thread function itself inside a SEH try/except block + wxSEH_TRY + { + if ( hasExited ) + DoThreadOnExit(thread); + else + rc = DoThreadStart(thread); + } + wxSEH_HANDLE(THREAD_ERROR_EXIT) + + + // save IsDetached because thread object can be deleted by joinable + // threads after state is changed to STATE_EXITED. + const bool isDetached = thread->IsDetached(); + if ( !hasExited ) + { // enter m_critsect before changing the thread state + // + // NB: can't use wxCriticalSectionLocker here as we use SEH and it's + // incompatible with C++ object dtors thread->m_critsect.Enter(); - wasCancelled = thread->m_internal->GetState() == STATE_CANCELED; thread->m_internal->SetState(STATE_EXITED); thread->m_critsect.Leave(); } - thread->OnExit(); - - // if the thread was cancelled (from Delete()), then its handle is still - // needed there - if ( thread->IsDetached() && !wasCancelled ) - { - // auto delete - delete thread; - } - //else: the joinable threads handle will be closed when Wait() is done + // the thread may delete itself now if it wants, we don't need it any more + if ( isDetached ) + thread->m_internal->LetDie(); return rc; } @@ -679,7 +585,7 @@ void wxThreadInternal::SetPriority(unsigned int priority) { m_priority = priority; - // translate wxWindows priority to the Windows one + // translate wxWidgets priority to the Windows one int win_priority; if (m_priority <= 20) win_priority = THREAD_PRIORITY_LOWEST; @@ -705,6 +611,9 @@ void wxThreadInternal::SetPriority(unsigned int priority) bool wxThreadInternal::Create(wxThread *thread, unsigned int stackSize) { + wxASSERT_MSG( m_state == STATE_NEW && !m_hThread, + _T("Create()ing thread twice?") ); + // for compilers which have it, we should use C RTL function for thread // creation instead of Win32 API one because otherwise we will have memory // leaks if the thread uses C RTL (and most threads do) @@ -742,7 +651,7 @@ bool wxThreadInternal::Create(wxThread *thread, unsigned int stackSize) { wxLogSysError(_("Can't create thread")); - return FALSE; + return false; } if ( m_priority != WXTHREAD_DEFAULT_PRIORITY ) @@ -750,7 +659,195 @@ bool wxThreadInternal::Create(wxThread *thread, unsigned int stackSize) SetPriority(m_priority); } - return TRUE; + return true; +} + +wxThreadError wxThreadInternal::Kill() +{ + if ( !::TerminateThread(m_hThread, THREAD_ERROR_EXIT) ) + { + wxLogSysError(_("Couldn't terminate thread")); + + return wxTHREAD_MISC_ERROR; + } + + Free(); + + return wxTHREAD_NO_ERROR; +} + +wxThreadError +wxThreadInternal::WaitForTerminate(wxCriticalSection& cs, + wxThread::ExitCode *pRc, + wxThread *threadToDelete) +{ + // prevent the thread C++ object from disappearing as long as we are using + // it here + wxThreadKeepAlive keepAlive(*this); + + + // we may either wait passively for the thread to terminate (when called + // from Wait()) or ask it to terminate (when called from Delete()) + bool shouldDelete = threadToDelete != NULL; + + DWORD rc = 0; + + // we might need to resume the thread if it's currently stopped + bool shouldResume = false; + + // as Delete() (which calls us) is always safe to call we need to consider + // all possible states + { + wxCriticalSectionLocker lock(cs); + + if ( m_state == STATE_NEW ) + { + if ( shouldDelete ) + { + // WinThreadStart() will see it and terminate immediately, no + // need to cancel the thread -- but we still need to resume it + // to let it run + m_state = STATE_EXITED; + + // we must call Resume() as the thread hasn't been initially + // resumed yet (and as Resume() it knows about STATE_EXITED + // special case, it won't touch it and WinThreadStart() will + // just exit immediately) + shouldResume = true; + shouldDelete = false; + } + //else: shouldResume is correctly set to false here, wait until + // someone else runs the thread and it finishes + } + else // running, paused, cancelled or even exited + { + shouldResume = m_state == STATE_PAUSED; + } + } + + // resume the thread if it is paused + if ( shouldResume ) + Resume(); + + // ask the thread to terminate + if ( shouldDelete ) + { + wxCriticalSectionLocker lock(cs); + + Cancel(); + } + + + // now wait for thread to finish + if ( wxThread::IsMain() ) + { + // set flag for wxIsWaitingForThread() + gs_waitingForThread = true; + } + + // we can't just wait for the thread to terminate because it might be + // calling some GUI functions and so it will never terminate before we + // process the Windows messages that result from these functions + // (note that even in console applications we might have to process + // messages if we use wxExecute() or timers or ...) + DWORD result wxDUMMY_INITIALIZE(0); + do + { + if ( wxThread::IsMain() ) + { + // give the thread we're waiting for chance to do the GUI call + // it might be in + if ( (gs_nWaitingForGui > 0) && wxGuiOwnedByMainThread() ) + { + wxMutexGuiLeave(); + } + } + + wxAppTraits *traits = wxTheApp ? wxTheApp->GetTraits() : NULL; + if ( traits ) + { + result = traits->WaitForThread(m_hThread); + } + else // can't wait for the thread + { + // so kill it below + result = 0xFFFFFFFF; + } + + switch ( result ) + { + case 0xFFFFFFFF: + // error + wxLogSysError(_("Can not wait for thread termination")); + Kill(); + return wxTHREAD_KILLED; + + case WAIT_OBJECT_0: + // thread we're waiting for terminated + break; + + case WAIT_OBJECT_0 + 1: + // new message arrived, process it -- but only if we're the + // main thread as we don't support processing messages in + // the other ones + // + // NB: we still must include QS_ALLINPUT even when waiting + // in a secondary thread because if it had created some + // window somehow (possible not even using wxWidgets) + // the system might dead lock then + if ( wxThread::IsMain() ) + { + if ( traits && !traits->DoMessageFromThreadWait() ) + { + // WM_QUIT received: kill the thread + Kill(); + + return wxTHREAD_KILLED; + } + } + break; + + default: + wxFAIL_MSG(wxT("unexpected result of MsgWaitForMultipleObject")); + } + } while ( result != WAIT_OBJECT_0 ); + + if ( wxThread::IsMain() ) + { + gs_waitingForThread = false; + } + + + // although the thread might be already in the EXITED state it might not + // have terminated yet and so we are not sure that it has actually + // terminated if the "if" above hadn't been taken + for ( ;; ) + { + if ( !::GetExitCodeThread(m_hThread, &rc) ) + { + wxLogLastError(wxT("GetExitCodeThread")); + + rc = THREAD_ERROR_EXIT; + + break; + } + + if ( rc != STILL_ACTIVE ) + break; + + // give the other thread some time to terminate, otherwise we may be + // starving it + ::Sleep(1); + } + + if ( pRc ) + *pRc = wxUIntToPtr(rc); + + // we don't need the thread handle any more in any case + Free(); + + + return rc == THREAD_ERROR_EXIT ? wxTHREAD_MISC_ERROR : wxTHREAD_NO_ERROR; } bool wxThreadInternal::Suspend() @@ -760,12 +857,12 @@ bool wxThreadInternal::Suspend() { wxLogSysError(_("Can not suspend thread %x"), m_hThread); - return FALSE; + return false; } m_state = STATE_PAUSED; - return TRUE; + return true; } bool wxThreadInternal::Resume() @@ -775,18 +872,18 @@ bool wxThreadInternal::Resume() { wxLogSysError(_("Can not resume thread %x"), m_hThread); - return FALSE; + return false; } // don't change the state from STATE_EXITED because it's special and means // we are going to terminate without running any user code - if we did it, - // the codei n Delete() wouldn't work + // the code in WaitForTerminate() wouldn't work if ( m_state != STATE_EXITED ) { m_state = STATE_RUNNING; } - return TRUE; + return true; } // static functions @@ -809,13 +906,9 @@ wxThread *wxThread::This() bool wxThread::IsMain() { - return ::GetCurrentThreadId() == gs_idMainThread; + return ::GetCurrentThreadId() == gs_idMainThread || gs_idMainThread == 0; } -#ifdef Yield -#undef Yield -#endif - void wxThread::Yield() { // 0 argument to Sleep() is special and means to just give away the rest of @@ -841,8 +934,11 @@ unsigned long wxThread::GetCurrentId() return (unsigned long)::GetCurrentThreadId(); } -bool wxThread::SetConcurrency(size_t level) +bool wxThread::SetConcurrency(size_t WXUNUSED_IN_WINCE(level)) { +#ifdef __WXWINCE__ + return false; +#else wxASSERT_MSG( IsMain(), _T("should only be called from the main thread") ); // ok only for the default one @@ -851,12 +947,12 @@ bool wxThread::SetConcurrency(size_t level) // get system affinity mask first HANDLE hProcess = ::GetCurrentProcess(); - DWORD dwProcMask, dwSysMask; + DWORD_PTR dwProcMask, dwSysMask; if ( ::GetProcessAffinityMask(hProcess, &dwProcMask, &dwSysMask) == 0 ) { wxLogLastError(_T("GetProcessAffinityMask")); - return FALSE; + return false; } // how many CPUs have we got? @@ -879,7 +975,7 @@ bool wxThread::SetConcurrency(size_t level) dwProcMask |= bit; // another process added - if ( !--level ) + if ( --level == 0 ) { // and that's enough break; @@ -895,13 +991,13 @@ bool wxThread::SetConcurrency(size_t level) { wxLogDebug(_T("bad level %u in wxThread::SetConcurrency()"), level); - return FALSE; + return false; } // set it: we can't link to SetProcessAffinityMask() because it doesn't // exist in Win9x, use RT binding instead - typedef BOOL (*SETPROCESSAFFINITYMASK)(HANDLE, DWORD); + typedef BOOL (WINAPI *SETPROCESSAFFINITYMASK)(HANDLE, DWORD_PTR); // can use static var because we're always in the main thread here static SETPROCESSAFFINITYMASK pfnSetProcessAffinityMask = NULL; @@ -923,17 +1019,18 @@ bool wxThread::SetConcurrency(size_t level) if ( !pfnSetProcessAffinityMask ) { // msg given above - do it only once - return FALSE; + return false; } if ( pfnSetProcessAffinityMask(hProcess, dwProcMask) == 0 ) { wxLogLastError(_T("SetProcessAffinityMask")); - return FALSE; + return false; } - return TRUE; + return true; +#endif // __WXWINCE__/!__WXWINCE__ } // ctor and dtor @@ -941,7 +1038,7 @@ bool wxThread::SetConcurrency(size_t level) wxThread::wxThread(wxThreadKind kind) { - m_internal = new wxThreadInternal(); + m_internal = new wxThreadInternal(this); m_isDetached = kind == wxTHREAD_DETACHED; } @@ -1000,181 +1097,21 @@ wxThreadError wxThread::Resume() wxThread::ExitCode wxThread::Wait() { + ExitCode rc = (ExitCode)THREAD_ERROR_EXIT; + // although under Windows we can wait for any thread, it's an error to // wait for a detached one in wxWin API - wxCHECK_MSG( !IsDetached(), (ExitCode)-1, - _T("can't wait for detached thread") ); + wxCHECK_MSG( !IsDetached(), rc, + _T("wxThread::Wait(): can't wait for detached thread") ); - ExitCode rc = (ExitCode)-1; - - (void)Delete(&rc); - - m_internal->Free(); + (void)m_internal->WaitForTerminate(m_critsect, &rc); return rc; } wxThreadError wxThread::Delete(ExitCode *pRc) { - ExitCode rc = 0; - - // Delete() is always safe to call, so consider all possible states - - // we might need to resume the thread, but we might also not need to cancel - // it if it doesn't run yet - bool shouldResume = FALSE, - shouldCancel = TRUE, - isRunning = FALSE; - - // check if the thread already started to run - { - wxCriticalSectionLocker lock(m_critsect); - - if ( m_internal->GetState() == STATE_NEW ) - { - // WinThreadStart() will see it and terminate immediately, no need - // to cancel the thread - but we still need to resume it to let it - // run - m_internal->SetState(STATE_EXITED); - - Resume(); // it knows about STATE_EXITED special case - - shouldCancel = FALSE; - isRunning = TRUE; - - // shouldResume is correctly set to FALSE here - } - else - { - shouldResume = IsPaused(); - } - } - - // resume the thread if it is paused - if ( shouldResume ) - Resume(); - - HANDLE hThread = m_internal->GetHandle(); - - // does is still run? - if ( isRunning || IsRunning() ) - { - if ( IsMain() ) - { - // set flag for wxIsWaitingForThread() - gs_waitingForThread = TRUE; - -#if wxUSE_GUI - wxBeginBusyCursor(); -#endif // wxUSE_GUI - } - - // ask the thread to terminate - if ( shouldCancel ) - { - wxCriticalSectionLocker lock(m_critsect); - - m_internal->Cancel(); - } - -#if wxUSE_GUI - // we can't just wait for the thread to terminate because it might be - // calling some GUI functions and so it will never terminate before we - // process the Windows messages that result from these functions - DWORD result; - do - { - result = ::MsgWaitForMultipleObjects - ( - 1, // number of objects to wait for - &hThread, // the objects - FALSE, // don't wait for all objects - INFINITE, // no timeout - QS_ALLEVENTS // return as soon as there are any events - ); - - switch ( result ) - { - case 0xFFFFFFFF: - // error - wxLogSysError(_("Can not wait for thread termination")); - Kill(); - return wxTHREAD_KILLED; - - case WAIT_OBJECT_0: - // thread we're waiting for terminated - break; - - case WAIT_OBJECT_0 + 1: - // new message arrived, process it - if ( !wxTheApp->DoMessage() ) - { - // WM_QUIT received: kill the thread - Kill(); - - return wxTHREAD_KILLED; - } - - if ( IsMain() ) - { - // give the thread we're waiting for chance to exit - // from the GUI call it might have been in - if ( (gs_nWaitingForGui > 0) && wxGuiOwnedByMainThread() ) - { - wxMutexGuiLeave(); - } - } - - break; - - default: - wxFAIL_MSG(wxT("unexpected result of MsgWaitForMultipleObject")); - } - } while ( result != WAIT_OBJECT_0 ); -#else // !wxUSE_GUI - // simply wait for the thread to terminate - // - // OTOH, even console apps create windows (in wxExecute, for WinSock - // &c), so may be use MsgWaitForMultipleObject() too here? - if ( WaitForSingleObject(hThread, INFINITE) != WAIT_OBJECT_0 ) - { - wxFAIL_MSG(wxT("unexpected result of WaitForSingleObject")); - } -#endif // wxUSE_GUI/!wxUSE_GUI - - if ( IsMain() ) - { - gs_waitingForThread = FALSE; - -#if wxUSE_GUI - wxEndBusyCursor(); -#endif // wxUSE_GUI - } - } - - if ( !::GetExitCodeThread(hThread, (LPDWORD)&rc) ) - { - wxLogLastError(wxT("GetExitCodeThread")); - - rc = (ExitCode)-1; - } - - if ( IsDetached() ) - { - // if the thread exits normally, this is done in WinThreadStart, but in - // this case it would have been too early because - // MsgWaitForMultipleObject() would fail if the thread handle was - // closed while we were waiting on it, so we must do it here - delete this; - } - - wxASSERT_MSG( (DWORD)rc != STILL_ACTIVE, - wxT("thread must be already terminated.") ); - - if ( pRc ) - *pRc = rc; - - return rc == (ExitCode)-1 ? wxTHREAD_MISC_ERROR : wxTHREAD_NO_ERROR; + return m_internal->WaitForTerminate(m_critsect, pRc, this); } wxThreadError wxThread::Kill() @@ -1182,21 +1119,20 @@ wxThreadError wxThread::Kill() if ( !IsRunning() ) return wxTHREAD_NOT_RUNNING; - if ( !::TerminateThread(m_internal->GetHandle(), (DWORD)-1) ) - { - wxLogSysError(_("Couldn't terminate thread")); - - return wxTHREAD_MISC_ERROR; - } - - m_internal->Free(); + wxThreadError rc = m_internal->Kill(); if ( IsDetached() ) { delete this; } + else // joinable + { + // update the status of the joinable thread + wxCriticalSectionLocker lock(m_critsect); + m_internal->SetState(STATE_EXITED); + } - return wxTHREAD_NO_ERROR; + return rc; } void wxThread::Exit(ExitCode status) @@ -1207,9 +1143,15 @@ void wxThread::Exit(ExitCode status) { delete this; } + else // joinable + { + // update the status of the joinable thread + wxCriticalSectionLocker lock(m_critsect); + m_internal->SetState(STATE_EXITED); + } #ifdef wxUSE_BEGIN_THREAD - _endthreadex((unsigned)status); + _endthreadex(wxPtrToUInt(status)); #else // !VC++ ::ExitThread((DWORD)status); #endif // VC++/!VC++ @@ -1297,7 +1239,7 @@ bool wxThreadModule::OnInit() // words, this should never happen wxLogSysError(_("Thread module initialization failed: impossible to allocate index in thread local storage")); - return FALSE; + return false; } // main thread doesn't have associated wxThread object, so store 0 in the @@ -1309,7 +1251,7 @@ bool wxThreadModule::OnInit() wxLogSysError(_("Thread module initialization failed: can not store value in thread local storage")); - return FALSE; + return false; } gs_critsectWaitingForGui = new wxCriticalSection(); @@ -1317,10 +1259,12 @@ bool wxThreadModule::OnInit() gs_critsectGui = new wxCriticalSection(); gs_critsectGui->Enter(); + gs_critsectThreadDelete = new wxCriticalSection; + // no error return for GetCurrentThreadId() gs_idMainThread = ::GetCurrentThreadId(); - return TRUE; + return true; } void wxThreadModule::OnExit() @@ -1330,6 +1274,9 @@ void wxThreadModule::OnExit() wxLogLastError(wxT("TlsFree failed.")); } + delete gs_critsectThreadDelete; + gs_critsectThreadDelete = NULL; + if ( gs_critsectGui ) { gs_critsectGui->Leave(); @@ -1346,7 +1293,7 @@ void wxThreadModule::OnExit() // not a mutex, so the names are a bit confusing // ---------------------------------------------------------------------------- -void WXDLLEXPORT wxMutexGuiEnter() +void wxMutexGuiEnterImpl() { // this would dead lock everything... wxASSERT_MSG( !wxThread::IsMain(), @@ -1368,13 +1315,13 @@ void WXDLLEXPORT wxMutexGuiEnter() gs_critsectGui->Enter(); } -void WXDLLEXPORT wxMutexGuiLeave() +void wxMutexGuiLeaveImpl() { wxCriticalSectionLocker enter(*gs_critsectWaitingForGui); if ( wxThread::IsMain() ) { - gs_bGuiOwnedByMainThread = FALSE; + gs_bGuiOwnedByMainThread = false; } else { @@ -1390,7 +1337,7 @@ void WXDLLEXPORT wxMutexGuiLeave() gs_critsectGui->Leave(); } -void WXDLLEXPORT wxMutexGuiLeaveOrEnter() +void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter() { wxASSERT_MSG( wxThread::IsMain(), wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") ); @@ -1405,7 +1352,7 @@ void WXDLLEXPORT wxMutexGuiLeaveOrEnter() { gs_critsectGui->Enter(); - gs_bGuiOwnedByMainThread = TRUE; + gs_bGuiOwnedByMainThread = true; } //else: already have it, nothing to do } @@ -1420,13 +1367,13 @@ void WXDLLEXPORT wxMutexGuiLeaveOrEnter() } } -bool WXDLLEXPORT wxGuiOwnedByMainThread() +bool WXDLLIMPEXP_BASE wxGuiOwnedByMainThread() { return gs_bGuiOwnedByMainThread; } // wake up the main thread if it's in ::GetMessage() -void WXDLLEXPORT wxWakeUpMainThread() +void WXDLLIMPEXP_BASE wxWakeUpMainThread() { // sending any message would do - hopefully WM_NULL is harmless enough if ( !::PostThreadMessage(gs_idMainThread, WM_NULL, 0, 0) ) @@ -1436,11 +1383,15 @@ void WXDLLEXPORT wxWakeUpMainThread() } } -bool WXDLLEXPORT wxIsWaitingForThread() +bool WXDLLIMPEXP_BASE wxIsWaitingForThread() { return gs_waitingForThread; } -#endif // wxUSE_THREADS +// ---------------------------------------------------------------------------- +// include common implementation code +// ---------------------------------------------------------------------------- + +#include "wx/thrimpl.cpp" -// vi:sts=4:sw=4:et +#endif // wxUSE_THREADS