// -*- C++ -*- //============================================================================= /** * @file Select_Reactor_T.h * * @author Douglas C. Schmidt */ //============================================================================= #ifndef ACE_SELECT_REACTOR_T_H #define ACE_SELECT_REACTOR_T_H #include /**/ "ace/pre.h" #include "ace/Select_Reactor_Base.h" #if !defined (ACE_LACKS_PRAGMA_ONCE) # pragma once #endif /* ACE_LACKS_PRAGMA_ONCE */ #include "ace/Lock_Adapter_T.h" #include "ace/Token.h" ACE_BEGIN_VERSIONED_NAMESPACE_DECL #if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0) typedef ACE_Token ACE_SELECT_TOKEN; #else typedef ACE_Noop_Token ACE_SELECT_TOKEN; #endif /* ACE_MT_SAFE && ACE_MT_SAFE != 0 */ /** * @class ACE_Select_Reactor_T * * @brief An object oriented event demultiplexor and event handler * dispatcher. * * The ACE_Select_Reactor is an object-oriented event * demultiplexor and event handler dispatcher. The sources of * events that the ACE_Select_Reactor waits for and dispatches * includes I/O events, signals, and timer events. All public * methods acquire the main ACE_Reactor_Token lock and * call down to private or protected methods, which assume that * the lock is held and so therefore don't (re)acquire the lock. */ template class ACE_Select_Reactor_T : public ACE_Select_Reactor_Impl { public: /// If @a disable_notify_pipe is non-0 then the reactor will /// not create a notification pipe, which will save two I/O handles /// but will elide the notify() feature. If @a mask_signals is /// true the reactor is "signal-safe" when dispatching handlers to /// signal events, whereas if @a mask_signals is false the reactor will /// be more efficient, but not signal-safe (which may be perfectly /// fine if your application doesn't use the reactor to handle signals). ACE_Select_Reactor_T (ACE_Sig_Handler * = 0, ACE_Timer_Queue * = 0, int disable_notify_pipe = ACE_DISABLE_NOTIFY_PIPE_DEFAULT, ACE_Reactor_Notify *notify = 0, bool mask_signals = true, int s_queue = ACE_SELECT_TOKEN::FIFO); /// Initialize @c ACE_Select_Reactor with size @arg size. /// If @arg disable_notify_pipe is non-0 then the reactor will /// not create a notification pipe, which will save two I/O handles /// but will elide the notification feature. If @arg mask_signals is /// true the reactor is "signal-safe" when dispatching handlers to /// signal events, whereas if @arg mask_signals is false the reactor will /// be more efficient, but not signal-safe (which may be perfectly /// fine if your application doesn't use the reactor to handle signals). /** * @note On Unix platforms, the size parameter should be as large as * the maximum number of file descriptors allowed for a given * process. This is necessary since a file descriptor is used * to directly index the array of event handlers maintained by * the Reactor's handler repository. Direct indexing is used * for efficiency reasons. */ ACE_Select_Reactor_T (size_t size, bool restart = false, ACE_Sig_Handler * = 0, ACE_Timer_Queue * = 0, int disable_notify_pipe = ACE_DISABLE_NOTIFY_PIPE_DEFAULT, ACE_Reactor_Notify *notify = 0, bool mask_signals = true, int s_queue = ACE_SELECT_TOKEN::FIFO); /** * Initialize the @c ACE_Select_Reactor to manage * @arg max_number_of_handles. If @arg restart is non-0 then the * @c ACE_Reactor's @c handle_events method will be restarted * automatically when @c EINTR occurs. If @arg signal_handler or * @arg timer_queue are non-0 they are used as the signal handler and * timer queue, respectively. If @arg disable_notify_pipe is non-0 the * notification pipe is not created, thereby saving two I/O handles. * * @note On Unix platforms, the @a maximum_number_of_handles parameter * should be as large as the maximum number of file * descriptors allowed for a given process. This is necessary * since a file descriptor is used to directly index the array * of event handlers maintained by the Reactor's handler * repository. Direct indexing is used for efficiency * reasons. */ virtual int open (size_t max_number_of_handles = DEFAULT_SIZE, bool restart = false, ACE_Sig_Handler * = 0, ACE_Timer_Queue * = 0, int disable_notify_pipe = ACE_DISABLE_NOTIFY_PIPE_DEFAULT, ACE_Reactor_Notify * = 0); /// Returns -1 (not used in this implementation); virtual int current_info (ACE_HANDLE, size_t &size); /// Use a user specified signal handler instead. virtual int set_sig_handler (ACE_Sig_Handler *signal_handler); /// Set a user-specified timer queue. virtual int timer_queue (ACE_Timer_Queue *tq); /// Return the current ACE_Timer_Queue. virtual ACE_Timer_Queue *timer_queue () const; /// Close down the select_reactor and release all of its resources. virtual int close (); /// Close down the select_reactor and release all of its resources. virtual ~ACE_Select_Reactor_T (); // = Event loop drivers. /** * Returns non-zero if there are I/O events "ready" for dispatching, * but does not actually dispatch the event handlers. By default, * don't block while checking this, i.e., "poll". */ virtual int work_pending (const ACE_Time_Value &max_wait_time = ACE_Time_Value::zero); //@{ /** * This event loop driver that blocks for @a max_wait_time before * returning. It will return earlier if timer events, I/O events, * or signal events occur. Note that @a max_wait_time can be 0, in * which case this method blocks indefinitely until events occur. * * @a max_wait_time is decremented to reflect how much time this call * took. For instance, if a time value of 3 seconds is passed to * handle_events and an event occurs after 2 seconds, * @a max_wait_time will equal 1 second. This can be used if an * application wishes to handle events for some fixed amount of * time. * * Returns the total number of I/O and Timer ACE_Event_Handler's * that were dispatched, 0 if the @a max_wait_time elapsed without * dispatching any handlers, or -1 if something goes wrong. * * Current alertable_handle_events() is identical to * handle_events(). */ virtual int handle_events (ACE_Time_Value *max_wait_time = 0); virtual int alertable_handle_events (ACE_Time_Value *max_wait_time = 0); //@} //@{ /** * This method is just like the one above, except the * @a max_wait_time value is a reference and can therefore never be * NULL. * * Current is identical to * . */ virtual int handle_events (ACE_Time_Value &max_wait_time); virtual int alertable_handle_events (ACE_Time_Value &max_wait_time); //@} // = Event handling control. /** * Return the status of Reactor. If this function returns 0, the reactor is * actively handling events. If it returns non-zero, and * return -1 immediately. */ virtual int deactivated (); /** * Control whether the Reactor will handle any more incoming events or not. * If @a do_stop == 1, the Reactor will be disabled. By default, a reactor * is in active state and can be deactivated/reactived as wish. */ virtual void deactivate (int do_stop); // = Register and remove ACE_Event_Handlers. /** * Register a @a eh with a particular @a mask. Note that the * will call ACE_Event_Handler::get_handle() to * extract the underlying I/O handle. */ virtual int register_handler (ACE_Event_Handler *eh, ACE_Reactor_Mask mask); /** * Register a @a eh with a particular @a mask. Note that since the * @a handle is given the Select_Reactor will *not* call * ACE_Event_Handler::get_handle() to extract the underlying I/O * handle. */ virtual int register_handler (ACE_HANDLE handle, ACE_Event_Handler *eh, ACE_Reactor_Mask mask); #if defined (ACE_WIN32) // Originally this interface was available for all platforms, but // because ACE_HANDLE is an int on non-Win32 platforms, compilers // are not able to tell the difference between // register_handler(ACE_Event_Handler*,ACE_Reactor_Mask) and // register_handler(ACE_Event_Handler*,ACE_HANDLE). Therefore, we // have restricted this method to Win32 only. /// Not implemented. virtual int register_handler (ACE_Event_Handler *event_handler, ACE_HANDLE event_handle = ACE_INVALID_HANDLE); #endif /* ACE_WIN32 */ /// Not implemented. virtual int register_handler (ACE_HANDLE event_handle, ACE_HANDLE io_handle, ACE_Event_Handler *event_handler, ACE_Reactor_Mask mask); /// Register @a eh with all the @a handles in the . virtual int register_handler (const ACE_Handle_Set &handles, ACE_Event_Handler *eh, ACE_Reactor_Mask mask); /** * Register @a new_sh to handle the signal @a signum using the * @a new_disp. Returns the @a old_sh that was previously registered * (if any), along with the @a old_disp of the signal handler. */ virtual int register_handler (int signum, ACE_Event_Handler *new_sh, ACE_Sig_Action *new_disp = 0, ACE_Event_Handler **old_sh = 0, ACE_Sig_Action *old_disp = 0); /// Registers @a new_sh to handle a set of signals @a sigset using the /// @a new_disp. virtual int register_handler (const ACE_Sig_Set &sigset, ACE_Event_Handler *new_sh, ACE_Sig_Action *new_disp = 0); /** * Removes the @a mask binding of @a eh from the Select_Reactor. If * there are no more bindings for this @a eh then it is removed from * the Select_Reactor. Note that the Select_Reactor will call * to extract the underlying I/O * handle. */ virtual int remove_handler (ACE_Event_Handler *eh, ACE_Reactor_Mask mask); /** * Removes the @a mask bind of Event_Handler whose handle is * @a handle from the Select_Reactor. If there are no more bindings * for this @a eh then it is removed from the Select_Reactor. */ virtual int remove_handler (ACE_HANDLE handle, ACE_Reactor_Mask); /** * Removes all the @a mask bindings for handles in the @a handle_set * bind of Event_Handler. If there are no more bindings for any * of these handlers then they are removed from the Select_Reactor. */ virtual int remove_handler (const ACE_Handle_Set &handle_set, ACE_Reactor_Mask); /** * Remove the ACE_Event_Handler currently associated with @a signum. * @a sigkey is ignored in this implementation since there is only * one instance of a signal handler. Install the new disposition * (if given) and return the previous disposition (if desired by the * caller). Returns 0 on success and -1 if @a signum is invalid. */ virtual int remove_handler (int signum, ACE_Sig_Action *new_disp, ACE_Sig_Action *old_disp = 0, int sigkey = -1); /// Calls for every signal in @a sigset. virtual int remove_handler (const ACE_Sig_Set &sigset); // = Suspend and resume Handlers. /// Temporarily suspend the associated with @a eh. virtual int suspend_handler (ACE_Event_Handler *eh); /// Temporarily suspend the Event_Handler associated with @a handle. virtual int suspend_handler (ACE_HANDLE handle); /// Suspend all @a handles in handle set temporarily. virtual int suspend_handler (const ACE_Handle_Set &handles); /// Suspend all the in the Select_Reactor. virtual int suspend_handlers (); /// Resume a temporarily suspend Event_Handler associated with /// @a eh. virtual int resume_handler (ACE_Event_Handler *eh); /// Resume a temporarily suspended Event_Handler associated with /// @a handle. virtual int resume_handler (ACE_HANDLE handle); /// Resume all @a handles in handle set. virtual int resume_handler (const ACE_Handle_Set &handles); /// Resume all the in the Select_Reactor. virtual int resume_handlers (); /** * Return true if we any event associations were made by the reactor * for the handles that it waits on, false otherwise. Since the * Select_Reactor does not do any event associations, this function * always return false. */ virtual bool uses_event_associations (); // = Timer management. /** * Schedule an ACE_Event_Handler that will expire after an amount * of time. The return value of this method, a timer_id value, * uniquely identifies the event_handler in the ACE_Reactor's * internal list of timers. * This timer_id value can be used to cancel the timer * with the cancel_timer() call. * * @see cancel_timer() * @see reset_timer_interval() * * @param event_handler Event handler to schedule on reactor * @param arg Argument passed to the handle_timeout() method of event_handler * @param delay Time interval after which the timer will expire * @param interval Time interval after which the timer will be automatically * rescheduled * @return -1 on failure, a timer_id value on success */ virtual long schedule_timer (ACE_Event_Handler * event_handler, const void *arg, const ACE_Time_Value &delay, const ACE_Time_Value &interval = ACE_Time_Value::zero); /** * Resets the interval of the timer represented by @a timer_id to * @a interval, which is specified in relative time to the current * . If @a interval is equal to * ACE_Time_Value::zero, the timer will become a non-rescheduling * timer. Returns 0 if successful, -1 if not. */ virtual int reset_timer_interval (long timer_id, const ACE_Time_Value &interval); /** * Cancel all that match the address of * @a event_handler. If @a dont_call_handle_close is 0 then the * method of @a event_handler will be invoked. * Returns number of handler's cancelled. */ virtual int cancel_timer (ACE_Event_Handler *event_handler, int dont_call_handle_close = 1); /** * Cancel the single ACE_Event_Handler that matches the @a timer_id * value (which was returned from the method). If arg is * non-NULL then it will be set to point to the ``magic cookie'' * argument passed in when the Event_Handler was registered. This * makes it possible to free up the memory and avoid memory leaks. * If @a dont_call_handle_close is 0 then the method * of will be invoked. Returns 1 if cancellation * succeeded and 0 if the @a timer_id wasn't found. */ virtual int cancel_timer (long timer_id, const void **arg = 0, int dont_call_handle_close = 1); // = High-level Event_Handler scheduling operations /// ADD the dispatch MASK "bit" bound with the @a eh and the @a mask. virtual int schedule_wakeup (ACE_Event_Handler *eh, ACE_Reactor_Mask mask); /// ADD the dispatch MASK "bit" bound with the @a handle and the @a mask. virtual int schedule_wakeup (ACE_HANDLE handle, ACE_Reactor_Mask mask); /// CLR the dispatch MASK "bit" bound with the @a eh and the @a mask. virtual int cancel_wakeup (ACE_Event_Handler *eh, ACE_Reactor_Mask mask); /// CLR the dispatch MASK "bit" bound with the @a handle and the @a mask. virtual int cancel_wakeup (ACE_HANDLE handle, ACE_Reactor_Mask mask); // = Notification methods. /** * Called by a thread when it wants to unblock the Select_Reactor. * This wakeups the if currently blocked in *