enum wxMutexError
{
- wxMUTEX_NO_ERROR = 0,
- wxMUTEX_DEAD_LOCK, // Mutex has been already locked by THE CALLING thread
- wxMUTEX_BUSY, // Mutex has been already locked by ONE thread
- wxMUTEX_UNLOCKED,
- wxMUTEX_MISC_ERROR
+ wxMUTEX_NO_ERROR = 0,
+ 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
};
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_MISC_ERROR // Some other error
+ 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
wxMutex& operator=(const wxMutex&);
int m_locked;
- wxMutexInternal *p_internal;
+ wxMutexInternal *m_internal;
};
// a helper class which locks the mutex in the ctor and unlocks it in the dtor:
};
// ----------------------------------------------------------------------------
-// Condition handler.
+// Condition variable: allows to block the thread execution until something
+// happens (== condition is signaled)
// ----------------------------------------------------------------------------
class wxConditionInternal;
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();
+ // constructor & destructor
+ wxCondition();
+ ~wxCondition();
+
+ // wait until the condition is signaled
+ // waits indefinitely.
+ void Wait();
+ // waits until a signal is raised or the timeout elapses
+ bool Wait(unsigned long sec, unsigned long nsec);
+
+ // signal the condition
+ // wakes up one (and only one) of the waiting threads
+ void Signal();
+ // wakes up all threads waiting onthis condition
+ void Broadcast();
private:
- wxConditionInternal *p_internal;
+ wxConditionInternal *m_internal;
};
// ----------------------------------------------------------------------------
-// Thread management class
+// Thread class
// ----------------------------------------------------------------------------
-// FIXME Thread termination model is still unclear. Delete() should probably
-// have a timeout after which the thread must be Kill()ed.
+// 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)
+
class wxThreadInternal;
class WXDLLEXPORT wxThread
{
// NB: at least under MSW worker threads can not call ::wxSleep()!
static void Sleep(unsigned long milliseconds);
- // default constructor
- wxThread();
+ // 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();
+
+ // 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
- // function that change the thread state
// create a new thread - call Run() to start it
wxThreadError Create();
- // starts execution of the thread - from the moment Run() is called the
- // execution of wxThread::Entry() may start at any moment, caller
+ // starts execution of the thread - from the moment Run() is called
+ // the execution of wxThread::Entry() may start at any moment, caller
// shouldn't suppose that it starts after (or before) Run() returns.
wxThreadError Run();
- // stops the thread if it's running and deletes the wxThread object
- // freeing its memory. This function should also be called if the
- // Create() or Run() fails to free memory (otherwise it will be done by
- // the thread itself when it terminates). The return value is the
- // thread exit code if the thread was gracefully terminated, 0 if it
- // wasn't running and -1 if an error occured.
- ExitCode Delete();
+ // 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 thread was
- // killed (i.e. no errors occured).
+ // 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
+ // pause a running thread: as Delete(), this only works if the thread
+ // calls TestDestroy() regularly
wxThreadError Pause();
// resume a paused thread
// Get the current priority.
unsigned int GetPriority() const;
- // Get the thread ID - a platform dependent number which uniquely
- // identifies a thread inside a process
- unsigned long GetID() const;
-
// thread status inquiries
// Returns true if the thread is alive: i.e. running or suspended
bool IsAlive() const;
// Returns true if the thread is 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
+ unsigned long 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: this function should
// be called by the thread from time to time, otherwise the main thread
bool TestDestroy();
// exits from the current thread - can be called only from this thread
- void Exit(void *exitcode = 0);
-
- // destructor is private - user code can't delete thread objects, they will
- // auto-delete themselves (and thus must be always allocated on the heap).
- // Use Delete() or Kill() instead.
- //
- // NB: derived classes dtors shouldn't be public neither!
- virtual ~wxThread();
+ void Exit(ExitCode exitcode = 0);
// entry point for the thread - called by Run() and executes in the context
// of this thread.
friend class wxThreadInternal;
// the (platform-dependent) thread class implementation
- wxThreadInternal *p_internal;
+ wxThreadInternal *m_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;
};
// ----------------------------------------------------------------------------
// 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_LOCKER(name, cs) wxCriticalSectionLocker name(*cs)
+#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
// 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