X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/9fc3ad34c5326856aeebf02335244ae315cef688..567be1875494c4cb90a3bdff691f8545e4f6e41d:/src/msw/thread.cpp diff --git a/src/msw/thread.cpp b/src/msw/thread.cpp index 3ae5d7b979..46719dc9c2 100644 --- a/src/msw/thread.cpp +++ b/src/msw/thread.cpp @@ -1,12 +1,12 @@ ///////////////////////////////////////////////////////////////////////////// -// 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 ///////////////////////////////////////////////////////////////////////////// @@ -26,12 +26,16 @@ #endif #ifndef WX_PRECOMP - #include "wx/wx.h" + #include "wx/intl.h" + #include "wx/app.h" #endif #if wxUSE_THREADS +#include "wx/apptrait.h" + #include "wx/msw/private.h" +#include "wx/msw/missing.h" #include "wx/module.h" #include "wx/thread.h" @@ -41,8 +45,45 @@ #define _MT #endif -#ifdef __VISUALC__ +#if defined(__BORLANDC__) + #if !defined(__MT__) + // I can't set -tWM in the IDE (anyone?) so have to do this + #define __MT__ + #endif + + #if !defined(__MFC_COMPAT__) + // Needed to know about _beginthreadex etc.. + #define __MFC_COMPAT__ + #endif +#endif // BC++ + +// define wxUSE_BEGIN_THREAD if the compiler has _beginthreadex() function +// which should be used instead of Win32 ::CreateThread() if possible +#if defined(__VISUALC__) || \ + (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \ + (defined(__GNUG__) && defined(__MSVCRT__)) || \ + 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; + + // the calling convention of the thread function entry point + #define THREAD_CALLCONV __stdcall +#else + // the settings for CreateThread() + typedef DWORD THREAD_RETVAL; + #define THREAD_CALLCONV WINAPI #endif // ---------------------------------------------------------------------------- @@ -89,211 +130,371 @@ static size_t gs_nWaitingForGui = 0; static bool gs_waitingForThread = FALSE; // ============================================================================ -// Windows implementation of thread classes +// Windows implementation of thread and related classes // ============================================================================ // ---------------------------------------------------------------------------- -// wxMutex implementation +// wxCriticalSection +// ---------------------------------------------------------------------------- + +wxCriticalSection::wxCriticalSection() +{ + wxCOMPILE_TIME_ASSERT( sizeof(CRITICAL_SECTION) <= sizeof(wxCritSectBuffer), + wxCriticalSectionBufferTooSmall ); + + ::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); +} + +// ---------------------------------------------------------------------------- +// wxMutex // ---------------------------------------------------------------------------- class wxMutexInternal { public: - HANDLE p_mutex; + wxMutexInternal(wxMutexType mutexType); + ~wxMutexInternal(); + + bool IsOk() const { return m_mutex != NULL; } + + wxMutexError Lock() { return LockTimeout(INFINITE); } + wxMutexError TryLock() { return LockTimeout(0); } + wxMutexError Unlock(); + +private: + wxMutexError LockTimeout(DWORD milliseconds); + + HANDLE m_mutex; + + DECLARE_NO_COPY_CLASS(wxMutexInternal) }; -wxMutex::wxMutex() +// all mutexes are recursive under Win32 so we don't use mutexType +wxMutexInternal::wxMutexInternal(wxMutexType WXUNUSED(mutexType)) { - m_internal = new wxMutexInternal; - m_internal->p_mutex = CreateMutex(NULL, FALSE, NULL); - if ( !m_internal->p_mutex ) + // create a nameless (hence intra process and always private) mutex + m_mutex = ::CreateMutex + ( + NULL, // default secutiry attributes + FALSE, // not initially locked + NULL // no name + ); + + if ( !m_mutex ) { - wxLogSysError(_("Can not create mutex.")); + wxLogLastError(_T("CreateMutex()")); } - - m_locked = 0; } -wxMutex::~wxMutex() +wxMutexInternal::~wxMutexInternal() { - if (m_locked > 0) - wxLogDebug(wxT("Warning: freeing a locked mutex (%d locks)."), m_locked); - CloseHandle(m_internal->p_mutex); + if ( m_mutex ) + { + if ( !::CloseHandle(m_mutex) ) + { + wxLogLastError(_T("CloseHandle(mutex)")); + } + } } -wxMutexError wxMutex::Lock() +wxMutexError wxMutexInternal::LockTimeout(DWORD milliseconds) { - DWORD ret; - - ret = WaitForSingleObject(m_internal->p_mutex, INFINITE); - switch ( ret ) + DWORD rc = ::WaitForSingleObject(m_mutex, milliseconds); + if ( rc == WAIT_ABANDONED ) { - case WAIT_ABANDONED: - return wxMUTEX_BUSY; + // 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 ( rc ) + { case WAIT_OBJECT_0: // ok break; - case WAIT_FAILED: - wxLogSysError(_("Couldn't acquire a mutex lock")); - return wxMUTEX_MISC_ERROR; - case WAIT_TIMEOUT: + return wxMUTEX_BUSY; + + case WAIT_ABANDONED: // checked for above default: wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock")); - } - - m_locked++; - return wxMUTEX_NO_ERROR; -} + // fall through -wxMutexError wxMutex::TryLock() -{ - DWORD ret; - - ret = WaitForSingleObject(m_internal->p_mutex, 0); - if (ret == WAIT_TIMEOUT || ret == WAIT_ABANDONED) - return wxMUTEX_BUSY; + case WAIT_FAILED: + wxLogLastError(_T("WaitForSingleObject(mutex)")); + return wxMUTEX_MISC_ERROR; + } - m_locked++; return wxMUTEX_NO_ERROR; } -wxMutexError wxMutex::Unlock() +wxMutexError wxMutexInternal::Unlock() { - if (m_locked > 0) - m_locked--; - - BOOL ret = ReleaseMutex(m_internal->p_mutex); - if ( ret == 0 ) + if ( !::ReleaseMutex(m_mutex) ) { - wxLogSysError(_("Couldn't release a mutex")); + wxLogLastError(_T("ReleaseMutex()")); + return wxMUTEX_MISC_ERROR; } return wxMUTEX_NO_ERROR; } -// ---------------------------------------------------------------------------- -// wxCondition implementation -// ---------------------------------------------------------------------------- +// -------------------------------------------------------------------------- +// wxSemaphore +// -------------------------------------------------------------------------- -class wxConditionInternal +// a trivial wrapper around Win32 semaphore +class wxSemaphoreInternal { public: - wxConditionInternal() - { - event = ::CreateEvent( - NULL, // default secutiry - FALSE, // not manual reset - FALSE, // nonsignaled initially - NULL // nameless event - ); - if ( !event ) - { - wxLogSysError(_("Can not create event object.")); - } - waiters = 0; - } + wxSemaphoreInternal(int initialcount, int maxcount); + ~wxSemaphoreInternal(); - bool Wait(DWORD timeout) - { - waiters++; + bool IsOk() const { return m_semaphore != NULL; } - // FIXME this should be MsgWaitForMultipleObjects() as well probably - DWORD rc = ::WaitForSingleObject(event, timeout); + wxSemaError Wait() { return WaitTimeout(INFINITE); } - waiters--; + wxSemaError TryWait() + { + wxSemaError rc = WaitTimeout(0); + if ( rc == wxSEMA_TIMEOUT ) + rc = wxSEMA_BUSY; - return rc != WAIT_TIMEOUT; + return rc; } - ~wxConditionInternal() - { - if ( event ) - { - if ( !::CloseHandle(event) ) - { - wxLogLastError("CloseHandle(event)"); - } - } - } + wxSemaError WaitTimeout(unsigned long milliseconds); + + wxSemaError Post(); - HANDLE event; - int waiters; +private: + HANDLE m_semaphore; + + DECLARE_NO_COPY_CLASS(wxSemaphoreInternal) }; -wxCondition::wxCondition() +wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount) { - m_internal = new wxConditionInternal; -} +#ifndef __WXWINCE__ + if ( maxcount == 0 ) + { + // make it practically infinite + maxcount = INT_MAX; + } -wxCondition::~wxCondition() -{ - delete m_internal; + m_semaphore = ::CreateSemaphore + ( + NULL, // default security attributes + initialcount, + maxcount, + NULL // no name + ); +#endif + if ( !m_semaphore ) + { + wxLogLastError(_T("CreateSemaphore()")); + } } -void wxCondition::Wait() +wxSemaphoreInternal::~wxSemaphoreInternal() { - (void)m_internal->Wait(INFINITE); + if ( m_semaphore ) + { + if ( !::CloseHandle(m_semaphore) ) + { + wxLogLastError(_T("CloseHandle(semaphore)")); + } + } } -bool wxCondition::Wait(unsigned long sec, - unsigned long nsec) +wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long milliseconds) { - return m_internal->Wait(sec*1000 + nsec/1000000); -} + DWORD rc = ::WaitForSingleObject( m_semaphore, milliseconds ); -void wxCondition::Signal() -{ - // set the event to signaled: if a thread is already waiting on it, it will - // be woken up, otherwise the event will remain in the signaled state until - // someone waits on it. In any case, the system will return it to a non - // signalled state afterwards. If multiple threads are waiting, only one - // will be woken up. - if ( !::SetEvent(m_internal->event) ) + switch ( rc ) { - wxLogLastError("SetEvent"); + case WAIT_OBJECT_0: + return wxSEMA_NO_ERROR; + + case WAIT_TIMEOUT: + return wxSEMA_TIMEOUT; + + default: + wxLogLastError(_T("WaitForSingleObject(semaphore)")); } + + return wxSEMA_MISC_ERROR; } -void wxCondition::Broadcast() +wxSemaError wxSemaphoreInternal::Post() { - // this works because all these threads are already waiting and so each - // SetEvent() inside Signal() is really a PulseEvent() because the event - // state is immediately returned to non-signaled - for ( int i = 0; i < m_internal->waiters; i++ ) +#ifndef __WXWINCE__ + if ( !::ReleaseSemaphore(m_semaphore, 1, NULL /* ptr to previous count */) ) +#endif { - Signal(); + wxLogLastError(_T("ReleaseSemaphore")); + + return wxSEMA_MISC_ERROR; } + + return wxSEMA_NO_ERROR; } -// ---------------------------------------------------------------------------- -// wxCriticalSection implementation -// ---------------------------------------------------------------------------- +// -------------------------------------------------------------------------- +// wxCondition +// -------------------------------------------------------------------------- -wxCriticalSection::wxCriticalSection() +// Win32 doesn't have explicit support for the POSIX condition variables and +// the Win32 events have quite different semantics, so we reimplement the +// conditions from scratch using the mutexes and semaphores +class wxConditionInternal { - wxASSERT_MSG( sizeof(CRITICAL_SECTION) <= sizeof(m_buffer), - _T("must increase buffer size in wx/thread.h") ); +public: + wxConditionInternal(wxMutex& mutex); - ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer); + bool IsOk() const { return m_mutex.IsOk() && m_semaphore.IsOk(); } + + wxCondError Wait(); + wxCondError WaitTimeout(unsigned long milliseconds); + + wxCondError Signal(); + wxCondError Broadcast(); + +private: + // the number of threads currently waiting for this condition + LONG m_numWaiters; + + // the critical section protecting m_numWaiters + wxCriticalSection m_csWaiters; + + wxMutex& m_mutex; + wxSemaphore m_semaphore; + + DECLARE_NO_COPY_CLASS(wxConditionInternal) +}; + +wxConditionInternal::wxConditionInternal(wxMutex& mutex) + : m_mutex(mutex) +{ + // another thread can't access it until we return from ctor, so no need to + // protect access to m_numWaiters here + m_numWaiters = 0; } -wxCriticalSection::~wxCriticalSection() +wxCondError wxConditionInternal::Wait() { - ::DeleteCriticalSection((CRITICAL_SECTION *)m_buffer); + // increment the number of waiters + ::InterlockedIncrement(&m_numWaiters); + + 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 + wxSemaError err = m_semaphore.Wait(); + m_mutex.Lock(); + + return err == wxSEMA_NO_ERROR ? wxCOND_NO_ERROR : wxCOND_MISC_ERROR; } -void wxCriticalSection::Enter() +wxCondError wxConditionInternal::WaitTimeout(unsigned long milliseconds) { - ::EnterCriticalSection((CRITICAL_SECTION *)m_buffer); + ::InterlockedIncrement(&m_numWaiters); + + m_mutex.Unlock(); + + // a race condition can occur at this point in the code + // + // please see the comments in Wait(), for details + + wxSemaError err = m_semaphore.WaitTimeout(milliseconds); + + if ( err == wxSEMA_BUSY ) + { + // 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. + wxCriticalSectionLocker lock(m_csWaiters); + + err = m_semaphore.WaitTimeout(0); + + if ( err != wxSEMA_NO_ERROR ) + { + m_numWaiters--; + } + } + + m_mutex.Lock(); + + return err == wxSEMA_NO_ERROR ? wxCOND_NO_ERROR : wxCOND_MISC_ERROR; } -void wxCriticalSection::Leave() +wxCondError wxConditionInternal::Signal() { - ::LeaveCriticalSection((CRITICAL_SECTION *)m_buffer); + wxCriticalSectionLocker lock(m_csWaiters); + + if ( m_numWaiters > 0 ) + { + // increment the semaphore by 1 + if ( m_semaphore.Post() != wxSEMA_NO_ERROR ) + return wxCOND_MISC_ERROR; + + m_numWaiters--; + } + + return wxCOND_NO_ERROR; +} + +wxCondError wxConditionInternal::Broadcast() +{ + wxCriticalSectionLocker lock(m_csWaiters); + + while ( m_numWaiters > 0 ) + { + if ( m_semaphore.Post() != wxSEMA_NO_ERROR ) + return wxCOND_MISC_ERROR; + + m_numWaiters--; + } + + return wxCOND_NO_ERROR; } // ---------------------------------------------------------------------------- @@ -324,7 +525,7 @@ public: { if ( !::CloseHandle(m_hThread) ) { - wxLogLastError("CloseHandle(thread)"); + wxLogLastError(wxT("CloseHandle(thread)")); } m_hThread = 0; @@ -332,7 +533,16 @@ public: } // create a new (suspended) thread (for the given thread object) - bool Create(wxThread *thread); + 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(bool shouldCancel, + wxCriticalSection& cs, + wxThread::ExitCode *pRc); + + // kill the thread unconditionally + wxThreadError Kill(); // suspend/resume/terminate bool Suspend(); @@ -352,36 +562,52 @@ public: DWORD GetId() const { return m_tid; } // thread function - static DWORD WinThreadStart(wxThread *thread); + static THREAD_RETVAL THREAD_CALLCONV WinThreadStart(void *thread); private: 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 + + DECLARE_NO_COPY_CLASS(wxThreadInternal) }; -DWORD wxThreadInternal::WinThreadStart(wxThread *thread) +THREAD_RETVAL THREAD_CALLCONV wxThreadInternal::WinThreadStart(void *param) { - // store the thread object in the TLS - if ( !::TlsSetValue(gs_tlsThisThread, thread) ) - { - wxLogSysError(_("Can not start thread: error writing TLS.")); + THREAD_RETVAL rc; + bool wasCancelled; - return (DWORD)-1; + // 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 ) + { + rc = (THREAD_RETVAL)-1; + wasCancelled = TRUE; } + else // do run thread + { + // store the thread object in the TLS + if ( !::TlsSetValue(gs_tlsThisThread, thread) ) + { + wxLogSysError(_("Can not start thread: error writing TLS.")); - DWORD rc = (DWORD)thread->Entry(); + return (DWORD)-1; + } - // enter m_critsect before changing the thread state - thread->m_critsect.Enter(); - bool wasCancelled = thread->m_internal->GetState() == STATE_CANCELED; - thread->m_internal->SetState(STATE_EXITED); - thread->m_critsect.Leave(); + rc = (THREAD_RETVAL)thread->Entry(); + + // enter m_critsect before changing the thread state + 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 it the handle is still + // if the thread was cancelled (from Delete()), then its handle is still // needed there if ( thread->IsDetached() && !wasCancelled ) { @@ -421,31 +647,43 @@ void wxThreadInternal::SetPriority(unsigned int priority) } } -bool wxThreadInternal::Create(wxThread *thread) +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) -#ifdef __VISUALC__ - typedef unsigned (__stdcall *RtlThreadStart)(void *); - - m_hThread = (HANDLE)_beginthreadex(NULL, 0, - (RtlThreadStart) - wxThreadInternal::WinThreadStart, - thread, CREATE_SUSPENDED, - (unsigned int *)&m_tid); -#else // !VC++ +#ifdef wxUSE_BEGIN_THREAD + + // Watcom is reported to not like 0 stack size (which means "use default" + // for the other compilers and is also the default value for stackSize) +#ifdef __WATCOMC__ + if ( !stackSize ) + stackSize = 10240; +#endif // __WATCOMC__ + + m_hThread = (HANDLE)_beginthreadex + ( + NULL, // default security + stackSize, + wxThreadInternal::WinThreadStart, // entry point + thread, + CREATE_SUSPENDED, + (unsigned int *)&m_tid + ); +#else // compiler doesn't have _beginthreadex m_hThread = ::CreateThread ( NULL, // default security - 0, // default stack size - (LPTHREAD_START_ROUTINE) // thread entry point - wxThreadInternal::WinThreadStart, // + stackSize, // stack size + wxThreadInternal::WinThreadStart, // thread entry point (LPVOID)thread, // parameter CREATE_SUSPENDED, // flags &m_tid // [out] thread id ); -#endif // VC++/!VC++ +#endif // _beginthreadex/CreateThread if ( m_hThread == NULL ) { @@ -462,6 +700,184 @@ bool wxThreadInternal::Create(wxThread *thread) return TRUE; } +wxThreadError wxThreadInternal::Kill() +{ + if ( !::TerminateThread(m_hThread, (DWORD)-1) ) + { + wxLogSysError(_("Couldn't terminate thread")); + + return wxTHREAD_MISC_ERROR; + } + + Free(); + + return wxTHREAD_NO_ERROR; +} + +wxThreadError +wxThreadInternal::WaitForTerminate(bool shouldCancel, + wxCriticalSection& cs, + wxThread::ExitCode *pRc) +{ + wxThread::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, + isRunning = FALSE; + + // check if the thread already started to run + { + wxCriticalSectionLocker lock(cs); + + if ( m_state == STATE_NEW ) + { + if ( shouldCancel ) + { + // 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; + + Resume(); // it knows about STATE_EXITED special case + + shouldCancel = FALSE; + } + + isRunning = TRUE; + + // shouldResume is correctly set to FALSE here + } + else + { + shouldResume = m_state == STATE_PAUSED; + } + } + + // resume the thread if it is paused + if ( shouldResume ) + Resume(); + + // does is still run? + if ( isRunning || m_state == STATE_RUNNING ) + { + if ( wxThread::IsMain() ) + { + // set flag for wxIsWaitingForThread() + gs_waitingForThread = TRUE; + } + + // ask the thread to terminate + if ( shouldCancel ) + { + wxCriticalSectionLocker lock(cs); + + Cancel(); + } + + // 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 = 0; // suppress warnings from broken compilers + 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(); + } + } + + result = ::MsgWaitForMultipleObjects + ( + 1, // number of objects to wait for + &m_hThread, // the objects + FALSE, // don't wait for all objects + INFINITE, // no timeout + QS_ALLINPUT | // return as soon as there are any events + QS_ALLPOSTMESSAGE + ); + + 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 wxWindows) + // the system might dead lock then + if ( wxThread::IsMain() ) + { + // it looks that sometimes WAIT_OBJECT_0 + 1 is + // returned but there are no messages in the thread + // queue -- prevent DoMessageFromThreadWait() from + // blocking inside ::GetMessage() forever in this case + ::PostMessage(NULL, WM_NULL, 0, 0); + + wxAppTraits *traits = wxTheApp ? wxTheApp->GetTraits() + : NULL; + + 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 + do + { + if ( !::GetExitCodeThread(m_hThread, (LPDWORD)&rc) ) + { + wxLogLastError(wxT("GetExitCodeThread")); + + rc = (wxThread::ExitCode)-1; + } + } while ( (DWORD)rc == STILL_ACTIVE ); + + if ( pRc ) + *pRc = rc; + + return rc == (wxThread::ExitCode)-1 ? wxTHREAD_MISC_ERROR + : wxTHREAD_NO_ERROR; +} + bool wxThreadInternal::Suspend() { DWORD nSuspendCount = ::SuspendThread(m_hThread); @@ -487,7 +903,13 @@ bool wxThreadInternal::Resume() return FALSE; } - m_state = STATE_RUNNING; + // 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 + if ( m_state != STATE_EXITED ) + { + m_state = STATE_RUNNING; + } return TRUE; } @@ -515,6 +937,10 @@ bool wxThread::IsMain() return ::GetCurrentThreadId() == gs_idMainThread; } +#ifdef Yield +#undef Yield +#endif + void wxThread::Yield() { // 0 argument to Sleep() is special and means to just give away the rest of @@ -527,6 +953,115 @@ void wxThread::Sleep(unsigned long milliseconds) ::Sleep(milliseconds); } +int wxThread::GetCPUCount() +{ + SYSTEM_INFO si; + GetSystemInfo(&si); + + return si.dwNumberOfProcessors; +} + +unsigned long wxThread::GetCurrentId() +{ + return (unsigned long)::GetCurrentThreadId(); +} + +bool wxThread::SetConcurrency(size_t level) +{ +#ifndef __WXWINCE__ + wxASSERT_MSG( IsMain(), _T("should only be called from the main thread") ); + + // ok only for the default one + if ( level == 0 ) + return 0; + + // get system affinity mask first + HANDLE hProcess = ::GetCurrentProcess(); + DWORD dwProcMask, dwSysMask; + if ( ::GetProcessAffinityMask(hProcess, &dwProcMask, &dwSysMask) == 0 ) + { + wxLogLastError(_T("GetProcessAffinityMask")); + + return FALSE; + } + + // how many CPUs have we got? + if ( dwSysMask == 1 ) + { + // don't bother with all this complicated stuff - on a single + // processor system it doesn't make much sense anyhow + return level == 1; + } + + // calculate the process mask: it's a bit vector with one bit per + // processor; we want to schedule the process to run on first level + // CPUs + DWORD bit = 1; + while ( bit ) + { + if ( dwSysMask & bit ) + { + // ok, we can set this bit + dwProcMask |= bit; + + // another process added + if ( !--level ) + { + // and that's enough + break; + } + } + + // next bit + bit <<= 1; + } + + // could we set all bits? + if ( level != 0 ) + { + wxLogDebug(_T("bad level %u in wxThread::SetConcurrency()"), level); + + 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); + + // can use static var because we're always in the main thread here + static SETPROCESSAFFINITYMASK pfnSetProcessAffinityMask = NULL; + + if ( !pfnSetProcessAffinityMask ) + { + HMODULE hModKernel = ::LoadLibrary(_T("kernel32")); + if ( hModKernel ) + { + pfnSetProcessAffinityMask = (SETPROCESSAFFINITYMASK) + ::GetProcAddress(hModKernel, "SetProcessAffinityMask"); + } + + // we've discovered a MT version of Win9x! + wxASSERT_MSG( pfnSetProcessAffinityMask, + _T("this system has several CPUs but no SetProcessAffinityMask function?") ); + } + + if ( !pfnSetProcessAffinityMask ) + { + // msg given above - do it only once + return FALSE; + } + + if ( pfnSetProcessAffinityMask(hProcess, dwProcMask) == 0 ) + { + wxLogLastError(_T("SetProcessAffinityMask")); + + return FALSE; + } +#endif + return TRUE; +} + // ctor and dtor // ------------- @@ -545,11 +1080,11 @@ wxThread::~wxThread() // create/start thread // ------------------- -wxThreadError wxThread::Create() +wxThreadError wxThread::Create(unsigned int stackSize) { wxCriticalSectionLocker lock(m_critsect); - if ( !m_internal->Create(this) ) + if ( !m_internal->Create(this, stackSize) ) return wxTHREAD_NO_RESOURCE; return wxTHREAD_NO_ERROR; @@ -594,144 +1129,36 @@ wxThread::ExitCode wxThread::Wait() // 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") ); + _T("wxThread::Wait(): can't wait for detached thread") ); ExitCode rc = (ExitCode)-1; - (void)Delete(&rc); + (void)m_internal->WaitForTerminate(false, m_critsect, &rc); m_internal->Free(); + wxCriticalSectionLocker lock(m_critsect); + m_internal->SetState(STATE_EXITED); + return rc; } wxThreadError wxThread::Delete(ExitCode *pRc) { - ExitCode rc = 0; - - // Delete() is always safe to call, so consider all possible states - if ( IsPaused() ) - Resume(); - - HANDLE hThread = m_internal->GetHandle(); - - if ( IsRunning() ) - { - if ( IsMain() ) - { - // set flag for wxIsWaitingForThread() - gs_waitingForThread = TRUE; - -#if wxUSE_GUI - wxBeginBusyCursor(); -#endif // wxUSE_GUI - } - - // ask the thread to terminate - { - 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("GetExitCodeThread"); - - rc = (ExitCode)-1; - } + wxThreadError rc = m_internal->WaitForTerminate(true, m_critsect, pRc); 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 therad handle was - // closed while we were waiting on it, so we must do it here delete this; } + else // joinable + { + // update the status of the joinable thread + wxCriticalSectionLocker lock(m_critsect); + m_internal->SetState(STATE_EXITED); + } - 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 rc; } wxThreadError wxThread::Kill() @@ -739,21 +1166,20 @@ 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) @@ -764,8 +1190,14 @@ 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 __VISUALC__ +#ifdef wxUSE_BEGIN_THREAD _endthreadex((unsigned)status); #else // !VC++ ::ExitThread((DWORD)status); @@ -852,9 +1284,7 @@ bool wxThreadModule::OnInit() // in normal circumstances it will only happen if all other // TLS_MINIMUM_AVAILABLE (>= 64) indices are already taken - in other // words, this should never happen - wxLogSysError(_("Thread module initialization failed: " - "impossible to allocate index in thread " - "local storage")); + wxLogSysError(_("Thread module initialization failed: impossible to allocate index in thread local storage")); return FALSE; } @@ -866,8 +1296,7 @@ bool wxThreadModule::OnInit() ::TlsFree(gs_tlsThisThread); gs_tlsThisThread = 0xFFFFFFFF; - wxLogSysError(_("Thread module initialization failed: " - "can not store value in thread local storage")); + wxLogSysError(_("Thread module initialization failed: can not store value in thread local storage")); return FALSE; } @@ -887,7 +1316,7 @@ void wxThreadModule::OnExit() { if ( !::TlsFree(gs_tlsThisThread) ) { - wxLogLastError("TlsFree failed."); + wxLogLastError(wxT("TlsFree failed.")); } if ( gs_critsectGui ) @@ -906,7 +1335,7 @@ void wxThreadModule::OnExit() // not a mutex, so the names are a bit confusing // ---------------------------------------------------------------------------- -void WXDLLEXPORT wxMutexGuiEnter() +void WXDLLIMPEXP_BASE wxMutexGuiEnter() { // this would dead lock everything... wxASSERT_MSG( !wxThread::IsMain(), @@ -928,7 +1357,7 @@ void WXDLLEXPORT wxMutexGuiEnter() gs_critsectGui->Enter(); } -void WXDLLEXPORT wxMutexGuiLeave() +void WXDLLIMPEXP_BASE wxMutexGuiLeave() { wxCriticalSectionLocker enter(*gs_critsectWaitingForGui); @@ -938,7 +1367,7 @@ void WXDLLEXPORT wxMutexGuiLeave() } else { - // decrement the number of waiters now + // decrement the number of threads waiting for GUI access now wxASSERT_MSG( gs_nWaitingForGui > 0, wxT("calling wxMutexGuiLeave() without entering it first?") ); @@ -950,7 +1379,7 @@ void WXDLLEXPORT wxMutexGuiLeave() gs_critsectGui->Leave(); } -void WXDLLEXPORT wxMutexGuiLeaveOrEnter() +void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter() { wxASSERT_MSG( wxThread::IsMain(), wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") ); @@ -980,25 +1409,32 @@ 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) ) { // should never happen - wxLogLastError("PostThreadMessage(WM_NULL)"); + wxLogLastError(wxT("PostThreadMessage(WM_NULL)")); } } -bool WXDLLEXPORT wxIsWaitingForThread() +bool WXDLLIMPEXP_BASE wxIsWaitingForThread() { return gs_waitingForThread; } +// ---------------------------------------------------------------------------- +// include common implementation code +// ---------------------------------------------------------------------------- + +#include "wx/thrimpl.cpp" + #endif // wxUSE_THREADS +