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Diffstat (limited to 'ace/Dev_Poll_Reactor.h')
| -rw-r--r-- | ace/Dev_Poll_Reactor.h | 1281 |
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diff --git a/ace/Dev_Poll_Reactor.h b/ace/Dev_Poll_Reactor.h deleted file mode 100644 index 78b0949b7d3..00000000000 --- a/ace/Dev_Poll_Reactor.h +++ /dev/null @@ -1,1281 +0,0 @@ -// -*- C++ -*- - -// ========================================================================= -/** - * @file Dev_Poll_Reactor.h - * - * $Id$ - * - * @em Experimental @c /dev/poll (or Linux @c sys_epoll) based - * Reactor implementation. - * - * @author Ossama Othman <ossama@dre.vanderbilt.edu> - */ -// ========================================================================= - - -#ifndef ACE_DEV_POLL_REACTOR_H -#define ACE_DEV_POLL_REACTOR_H - -#include /**/ "ace/pre.h" - -#include "ace/ACE_export.h" - -#if !defined (ACE_LACKS_PRAGMA_ONCE) -# pragma once -#endif /* ACE_LACKS_PRAGMA_ONCE */ - -#if defined (ACE_HAS_EVENT_POLL) -// The sys_epoll interface was introduced in Linux kernel 2.5.45. -// Don't support backported versions since they appear to be buggy. -// The obsolete ioctl()-based interface is no longer supported. -#if 0 -// linux/version.h may not be accurate. It's not for Fedora Core 2... -# include /**/ <linux/version.h> -# if LINUX_VERSION_CODE < KERNEL_VERSION (2,5,45) -# undef ACE_HAS_EVENT_POLL -# error Disabling Linux epoll support. Kernel used in C library is too old. -# error Linux kernel 2.5.45 or better is required. -# endif /* LINUX_VERSION_CODE < KERNEL_VERSION (2,5,45) */ -#endif /* ACE_HAS_EVENT_POLL */ -#endif - -#if defined (ACE_HAS_EVENT_POLL) && defined (ACE_HAS_DEV_POLL) -# error ACE_HAS_EVENT_POLL and ACE_HAS_DEV_POLL are mutually exclusive. -#endif /* ACE_HAS_EVENT_POLL && defined ACE_HAS_DEV_POLL */ - - -#if defined (ACE_HAS_EVENT_POLL) || defined (ACE_HAS_DEV_POLL) - -#include "ace/Pipe.h" -#include "ace/Lock_Adapter_T.h" -#include "ace/Reactor_Impl.h" -#include "ace/Reactor_Token_T.h" -#include "ace/Token.h" - -#if defined (ACE_HAS_REACTOR_NOTIFICATION_QUEUE) -# include "ace/Unbounded_Queue.h" -#endif /* ACE_HAS_REACTOR_NOTIFICATION_QUEUE */ - -#if defined (ACE_HAS_DEV_POLL) -struct pollfd; -#elif defined (ACE_HAS_EVENT_POLL) -struct epoll_event; -#endif - -ACE_BEGIN_VERSIONED_NAMESPACE_DECL - -// Forward declarations -class ACE_Sig_Handler; -class ACE_Dev_Poll_Reactor; - -/** - * @class ACE_Dev_Poll_Event_Tuple - * - * @brief Class that associates specific event mask with a given event - * handler. - * - * This class merely provides a means to associate an event mask - * with an event handler. Such an association is needed since it is - * not possible to retrieve the event mask from the "interest set" - * stored in the `/dev/poll' or `/dev/epoll' driver. Without this - * external association, it would not be possible keep track of the - * event mask for a given event handler when suspending it or resuming - * it. - * - * @note An ACE_Handle_Set is not used since the number of handles may - * exceed its capacity (ACE_DEFAULT_SELECT_REACTOR_SIZE). - */ -class ACE_Dev_Poll_Event_Tuple -{ -public: - - /// Constructor. - ACE_Dev_Poll_Event_Tuple (void); - -public: - - /// The event handler. - ACE_Event_Handler *event_handler; - - /// The event mask for the above event handler. - ACE_Reactor_Mask mask; - - /// Flag that states whether or not the event handler is suspended. - char suspended; -}; - -// --------------------------------------------------------------------- - -#if 0 -/** - * @class ACE_Dev_Poll_Ready_Set - * - * @brief Class that contains the list of "ready" file descriptors. - * - * This class points to an array of pollfd structures corresponding to - * "ready" file descriptors, such as those corresponding to event - * handlers that request an additional callback after being initially - * dispatched (i.e. return a value greater than zero). - * @par - * The idea is to store the "ready" set in an existing area of memory - * that already contains pollfd instances. Doing so is safe since the - * "ready" set is dispatched before polling for additional events, - * thus avoiding being potentially overwritten during the event poll. - * @par - * When the "ready" set is dispatched, all that needs to be done is to - * iterate over the contents of the array. There is no need to "walk" - * the array in search of ready file descriptors since the array by - * design only contains ready file descriptors. As such, this - * implementation of a ready set is much more efficient in the - * presence of a large number of file descriptors in terms of both - * time and space than the one used in the Select_Reactor, for - * example. - */ -class ACE_Dev_Poll_Ready_Set -{ -public: - - /// Constructor. - ACE_Dev_Poll_Ready_Set (void); - -public: - - /// The array containing the pollfd structures corresponding to the - /// "ready" file descriptors. - struct pollfd *pfds; - - /// The number of "ready" file descriptors in the above array. - int nfds; - -}; -#endif /* 0 */ - -// --------------------------------------------------------------------- - -/** - * @class ACE_Dev_Poll_Reactor_Notify - * - * @brief Event handler used for unblocking the ACE_Dev_Poll_Reactor - * from its event loop. - * - * This event handler is used internally by the ACE_Dev_Poll_Reactor - * as a means to allow a thread other then the one running the event - * loop to unblock the event loop. - */ -class ACE_Dev_Poll_Reactor_Notify : public ACE_Reactor_Notify -{ -public: - - /// Constructor - ACE_Dev_Poll_Reactor_Notify (void); - - /** - * @name Initialization and Termination Methods - * - * Methods called when initializing and terminating this event - * handler. - */ - virtual int open (ACE_Reactor_Impl *, - ACE_Timer_Queue *timer_queue = 0, - int disable_notify = 0); - virtual int close (void); - - /** - * Called by a thread when it wants to unblock the Reactor_Impl. - * This wakes up the Reactor_Impl if currently blocked. Pass over - * both the Event_Handler and the mask to allow the caller to - * dictate which Event_Handler method the Reactor_Impl will - * invoke. The ACE_Time_Value indicates how long to block - * trying to notify the Reactor_Impl. If timeout == 0, the - * caller will block until action is possible, else will wait until - * the relative time specified in *timeout elapses). - */ - virtual int notify (ACE_Event_Handler *eh = 0, - ACE_Reactor_Mask mask = ACE_Event_Handler::EXCEPT_MASK, - ACE_Time_Value *timeout = 0); - - /// Unimplemented method required by pure virtual method in abstract - /// base class. - /** - * This method's interface is not very compatibile with this - * Reactor's design. It's not clear why this method is pure virtual - * either. - */ - virtual int dispatch_notifications (int &number_of_active_handles, - ACE_Handle_Set &rd_mask); - - /// Returns the ACE_HANDLE of the notify pipe on which the reactor - /// is listening for notifications so that other threads can unblock - /// the Reactor_Impl. - virtual ACE_HANDLE notify_handle (void); - - /// Verify whether the buffer has dispatchable info or not. - virtual int is_dispatchable (ACE_Notification_Buffer &buffer); - - /// Handle one notify call represented in @a buffer. This could be - /// because of a thread trying to unblock the Reactor_Impl. - virtual int dispatch_notify (ACE_Notification_Buffer &buffer); - - /// Read one notify call on the handle into @a buffer. - /// This could be because of a thread trying to unblock the Reactor_Impl. - virtual int read_notify_pipe (ACE_HANDLE handle, - ACE_Notification_Buffer &buffer); - - /// Called back by the ACE_Dev_Poll_Reactor when a thread wants to - /// unblock us. - virtual int handle_input (ACE_HANDLE handle); - - /** - * Set the maximum number of times that the handle_input method - * will iterate and dispatch the ACE_Event_Handlers that are - * passed in via the notify queue before breaking out of the event - * loop. By default, this is set to -1, which means "iterate until - * the queue is empty." Setting this to a value like "1 or 2" will - * increase "fairness" (and thus prevent starvation) at the expense - * of slightly higher dispatching overhead. - */ - virtual void max_notify_iterations (int); - - /** - * Get the maximum number of times that the handle_input method - * will iterate and dispatch the ACE_Event_Handlers that are - * passed in via the notify queue before breaking out of its event - * loop. - */ - virtual int max_notify_iterations (void); - - /** - * Purge any notifications pending in this reactor for the specified - * ACE_Event_Handler object. Returns the number of notifications - * purged. Returns -1 on error. - */ - virtual int purge_pending_notifications ( - ACE_Event_Handler * = 0, - ACE_Reactor_Mask = ACE_Event_Handler::ALL_EVENTS_MASK); - - /// Dump the state of an object. - virtual void dump (void) const; - -protected: - - /** - * Keep a back pointer to the ACE_Dev_Poll_Reactor. If this value - * if NULL then the ACE_Dev_Poll_Reactor has been initialized with - * disable_notify_pipe. - */ - ACE_Dev_Poll_Reactor *dp_reactor_; - - /** - * Contains the ACE_HANDLE the ACE_Dev_Poll_Reactor is listening - * on, as well as the ACE_HANDLE that threads wanting the attention - * of the ACE_Dev_Poll_Reactor will write to. - */ - ACE_Pipe notification_pipe_; - - /** - * Keeps track of the maximum number of times that the - * ACE_Dev_Poll_Reactor_Notify::handle_input method will iterate and - * dispatch the ACE_Event_Handlers that are passed in via the - * notify pipe before breaking out of its recv loop. By default, - * this is set to -1, which means "iterate until the pipe is empty." - */ - int max_notify_iterations_; - -#if defined (ACE_HAS_REACTOR_NOTIFICATION_QUEUE) - /** - * @name Reactor Notification Attributes - * - * This configuration queues up notifications in separate buffers - * that are in user-space, rather than stored in a pipe in the OS - * kernel. The kernel-level notifications are used only to trigger - * the Reactor to check its notification queue. This enables many - * more notifications to be stored than would otherwise be the - * case. - */ - //@{ - - /// ACE_Notification_Buffers are allocated in chunks. Each time a chunk is - /// allocated, the chunk is added to alloc_queue_ so it can be freed later. - /// Each individual ACE_Notification_Buffer is added to the free_queue_ - /// when it's free. Those in use for queued notifications are placed on the - /// notify_queue_. - ACE_Unbounded_Queue <ACE_Notification_Buffer *> alloc_queue_; - ACE_Unbounded_Queue <ACE_Notification_Buffer *> notify_queue_; - ACE_Unbounded_Queue <ACE_Notification_Buffer *> free_queue_; - - /// Synchronization for handling of queues. - ACE_SYNCH_MUTEX notify_queue_lock_; - - //@} -#endif /* ACE_HAS_REACTOR_NOTIFICATION_QUEUE */ - -}; - -// --------------------------------------------------------------------- - -/** - * @class ACE_Dev_Poll_Reactor_Handler_Repository - * - * @internal - - * @brief Used to map ACE_HANDLEs onto the appropriate - * ACE_Event_Handler *. - * - * - * This class is simply a container that maps a handle to its - * corresponding event handler. It is not meant for use outside of - * the Dev_Poll_Reactor. - */ -class ACE_Dev_Poll_Reactor_Handler_Repository -{ -public: - - /// Constructor. - ACE_Dev_Poll_Reactor_Handler_Repository (void); - - /// Initialize a repository of the appropriate <size>. - int open (size_t size); - - /// Close down the repository. - int close (void); - - /** - * @name Repository Manipulation Operations - * - * Methods used to search and modify the handler repository. - */ - //@{ - - /** - * Return the @c ACE_Event_Handler associated with @c ACE_HANDLE. If - * @a index_p is non-zero, then return the index location of the - * handle, if found. - */ - ACE_Event_Handler *find (ACE_HANDLE handle, size_t *index_p = 0); - - /// Set the event mask for event handler associated with the given - /// handle. - void mask (ACE_HANDLE handle, ACE_Reactor_Mask mask); - - /// Retrieve the event mask for the event handler associated with - /// the given handle. - ACE_Reactor_Mask mask (ACE_HANDLE handle); - - /// Mark the event handler associated with the given handle as - /// "suspended." - void suspend (ACE_HANDLE handle); - - /// Mark the event handler associated with the given handle as - /// "resumed." - void resume (ACE_HANDLE handle); - - /// Is the event handler for the given handle suspended? - int suspended (ACE_HANDLE handle) const; - - /// Bind the ACE_Event_Handler to the @c ACE_HANDLE with the - /// appropriate ACE_Reactor_Mask settings. - int bind (ACE_HANDLE handle, - ACE_Event_Handler *handler, - ACE_Reactor_Mask mask); - - /// Remove the binding for @c ACE_HANDLE; optionally decrement the associated - /// handler's reference count. - int unbind (ACE_HANDLE handle, bool decr_refcnt = true); - - /// Remove all the (@c ACE_HANDLE, @c ACE_Event_Handler) tuples. - int unbind_all (void); - - /** - * @name Sanity Checking - * - * Methods used to prevent "out-of-range" errors when indexing the - * underlying handler array. - */ - //@{ - - // Check the @a handle to make sure it's a valid @c ACE_HANDLE that - // within the range of legal handles (i.e., greater than or equal to - // zero and less than @c max_size_). - int invalid_handle (ACE_HANDLE handle) const; - - // Check the handle to make sure it's a valid @c ACE_HANDLE that is - // within the range of currently registered handles (i.e., greater - // than or equal to zero and less than @c max_handlep1_). - int handle_in_range (ACE_HANDLE handle) const; - - //@} - - /// Returns the current table size. - size_t size (void) const; - - /// Dump the state of an object. - void dump (void) const; - - /// Declare the dynamic allocation hooks. - ACE_ALLOC_HOOK_DECLARE; - -private: - - /// Maximum number of handles. - int max_size_; - - /// The underlying array of event handlers. - /** - * The array of event handlers is directly indexed directly using - * an @c ACE_HANDLE value. This is Unix-specific. - */ - ACE_Dev_Poll_Event_Tuple *handlers_; - -}; - -// --------------------------------------------------------------------- - -/** - * @class ACE_Dev_Poll_Reactor - * - * @brief A `/dev/poll' or `/dev/epoll' based Reactor implemenatation. - * - * @attention This reactor is @em experimental. - * - * The ACE_Dev_Poll_Reactor uses the `/dev/poll' or '/dev/epoll' - * character devices to demultiplex events on a given set of file - * descriptors. Unlike @c select(), `/dev/poll' and `/dev/epoll' have - * no hard-coded limit on the number of file descriptors that may be - * handled at any given time. As such, the ACE_Dev_Poll_Reactor can - * generally handle a much larger number of file descriptors than - * @c select() -based reactors. Furthermore, since `/dev/poll' and - * `/dev/epoll' both return a set of file descriptors that are active, - * there is no need to "walk" the set of file descriptors to determine - * which ones are active, such as what is done with the @c select() and - * @c poll() system calls. All returned file descriptors are active. - * This makes event dispatching very efficient. - * - * @note In general, this reactor may only be used to demultiplex - * events on sockets. Demultiplexing events on pipes, for - * example may not work. This is due to a limitation in the - * underlying `/dev/poll' device driver. - * - * @note It is only possible to achieve millisecond timeout - * resolutions with the @c ACE_Dev_Poll_Reactor. However, the - * timeout resolution for timers is independent of the reactors - * timeout resolution. As such, it may be possible to achieve - * sub-millisecond timeout resolutions for timers but that is - * entirely platform dependent. - */ - -#if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0) -typedef ACE_Token ACE_DEV_POLL_TOKEN; -#else -typedef ACE_Noop_Token ACE_DEV_POLL_TOKEN; -#endif /* ACE_MT_SAFE && ACE_MT_SAFE != 0 */ -typedef ACE_Reactor_Token_T<ACE_DEV_POLL_TOKEN> ACE_Dev_Poll_Reactor_Token; - -class ACE_Export ACE_Dev_Poll_Reactor : public ACE_Reactor_Impl -{ -public: - - /// Initialize @c ACE_Dev_Poll_Reactor with the default size. - /** - * The default size for the @c ACE_Dev_Poll_Reactor is the maximum - * number of open file descriptors for the process. - */ - ACE_Dev_Poll_Reactor (ACE_Sig_Handler * = 0, - ACE_Timer_Queue * = 0, - int disable_notify_pipe = 0, - ACE_Reactor_Notify *notify = 0, - int mask_signals = 1, - int s_queue = ACE_DEV_POLL_TOKEN::FIFO); - - /// Initialize ACE_Dev_Poll_Reactor with size @a size. - /** - * @note On Unix platforms, the @a 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. If the size - * parameter is less than the process maximum, the process - * maximum will be decreased in order to prevent potential - * access violations. - */ - ACE_Dev_Poll_Reactor (size_t size, - int restart = 0, - ACE_Sig_Handler * = 0, - ACE_Timer_Queue * = 0, - int disable_notify_pipe = 0, - ACE_Reactor_Notify *notify = 0, - int mask_signals = 1, - int s_queue = ACE_DEV_POLL_TOKEN::FIFO); - - /// Close down and release all resources. - virtual ~ACE_Dev_Poll_Reactor (void); - - /// Initialization. - virtual int open (size_t size, - int restart = 0, - ACE_Sig_Handler * = 0, - ACE_Timer_Queue * = 0, - int disable_notify_pipe = 0, - ACE_Reactor_Notify * = 0); - - /** - * @param handle allows the reactor to check if the caller is - * valid. - * - * @return 0 if the size of the current message has been put in - * size. -1 if not. - */ - virtual int current_info (ACE_HANDLE 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); - - /// Get the timer queue - /// @return The current @c ACE_Timer_Queue. - virtual ACE_Timer_Queue *timer_queue (void) const; - - /// Close down and release all resources. - virtual int close (void); - - // = 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". - * - * @note It is only possible to achieve millisecond timeout - * resolutions with the @c ACE_Dev_Poll_Reactor. - */ - virtual int work_pending ( - const ACE_Time_Value &max_wait_time = ACE_Time_Value::zero); - - /** - * This event loop driver blocks for up to @a max_wait_time before - * returning. It will return earlier if events occur. Note that - * @a max_wait_time can be 0, in which case this method blocks - * indefinitely until events occur. - * @par - * @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 @c 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. - * @par - * The only difference between @c alertable_handle_events() and - * handle_events() is that in the alertable case, the event loop - * will return when the system queues an I/O completion routine or - * an Asynchronous Procedure Call. - * - * @return The total number of @c ACE_Event_Handlers that were - * dispatched, 0 if the @a max_wait_time elapsed without - * dispatching any handlers, or -1 if an error occurs. - - * @note It is only possible to achieve millisecond timeout - * resolutions with the @c ACE_Dev_Poll_Reactor. - */ - 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 - * @c NULL. - * - * @note It is only possible to achieve millisecond timeout - * resolutions with the @c ACE_Dev_Poll_Reactor. - */ - 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, @c handle_events() and - * @c handle_alertable_events() return -1 immediately. - */ - virtual int deactivated (void); - - /** - * 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 desired. - */ - virtual void deactivate (int do_stop); - - // = Register and remove Handlers. - - /// Register @a event_handler with @a mask. The I/O handle will - /// always come from get_handle on the event_handler. - virtual int register_handler (ACE_Event_Handler *event_handler, - ACE_Reactor_Mask mask); - - /// Register @a event_handler with @a mask. The I/O handle is - /// provided through the @a io_handle parameter. - virtual int register_handler (ACE_HANDLE io_handle, - ACE_Event_Handler *event_handler, - ACE_Reactor_Mask mask); - - /** - * Register an @a event_handler that will be notified when - * @a event_handle is signaled. @a mask specifies the network - * events that the @a event_handler is interested in. - */ - virtual int register_handler (ACE_HANDLE event_handle, - ACE_HANDLE io_handle, - ACE_Event_Handler *event_handler, - ACE_Reactor_Mask mask); - - /// Register @a event_handler> with all the @a handles> in the @c - /// Handle_Set. - virtual int register_handler (const ACE_Handle_Set &handles, - ACE_Event_Handler *event_handler, - 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 <new_sh> to handle a set of signals <sigset> using the - /// <new_disp>. - virtual int register_handler (const ACE_Sig_Set &sigset, - ACE_Event_Handler *new_sh, - ACE_Sig_Action *new_disp = 0); - - /// Removes @a event_handler. - /** - * @note The I/O handle will be obtained using @c get_handle() - * method of @a event_handler . If @a mask == - * @c ACE_Event_Handler::DONT_CALL then the @c handle_close() - * method of the @a event_handler is not invoked. - */ - virtual int remove_handler (ACE_Event_Handler *event_handler, - ACE_Reactor_Mask mask); - - /** - * Removes <handle>. If <mask> == <ACE_Event_Handler::DONT_CALL> - * then the <handle_close> method of the associated <event_handler> - * is not invoked. - */ - virtual int remove_handler (ACE_HANDLE handle, - ACE_Reactor_Mask mask); - - /** - * Removes all handles in <handle_set>. If <mask> == - * <ACE_Event_Handler::DONT_CALL> then the <handle_close> method of - * the associated <event_handler>s is not invoked. - */ - virtual int remove_handler (const ACE_Handle_Set &handle_set, - ACE_Reactor_Mask mask); - - /** - * Remove the ACE_Event_Handler currently associated with <signum>. - * Install the new disposition (if given) and return the previous - * disposition (if desired by the caller). Returns 0 on success and - * -1 if <signum> is invalid. - */ - virtual int remove_handler (int signum, - ACE_Sig_Action *new_disp, - ACE_Sig_Action *old_disp = 0, - int sigkey = -1); - - /// Calls <remove_handler> for every signal in <sigset>. - virtual int remove_handler (const ACE_Sig_Set &sigset); - - // = Suspend and resume Handlers. - - /// Suspend event_handler temporarily. Use - /// ACE_Event_Handler::get_handle() to get the handle. - virtual int suspend_handler (ACE_Event_Handler *event_handler); - - /// Suspend handle temporarily. - virtual int suspend_handler (ACE_HANDLE handle); - - /// Suspend all handles in handle set temporarily. - virtual int suspend_handler (const ACE_Handle_Set &handles); - - /// Suspend all handles temporarily. - virtual int suspend_handlers (void); - - /// Resume event_handler. Use ACE_Event_Handler::get_handle() to - /// get the handle. - virtual int resume_handler (ACE_Event_Handler *event_handler); - - /// Resume handle. - virtual int resume_handler (ACE_HANDLE handle); - - /// Resume all handles in handle set. - virtual int resume_handler (const ACE_Handle_Set &handles); - - /// Resume all handles. - virtual int resume_handlers (void); - - /// Does the reactor allow the application to resume the handle on - /// its own, i.e., can it pass on the control of handle resumption to - /// the application. - virtual int resumable_handler (void); - - /// Return 1 if we any event associations were made by the reactor - /// for the handles that it waits on, 0 otherwise. - virtual int uses_event_associations (void); - - // = 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 for 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 <timer_id> to - * <interval>, which is specified in relative time to the current - * <gettimeofday>. If <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 Event_Handlers that match the address of - /// <event_handler>. Returns number of handlers cancelled. - virtual int cancel_timer (ACE_Event_Handler *event_handler, - int dont_call_handle_close = 1); - - /** - * Cancel the single event handler that matches the @a timer_id value - * (which was returned from the schedule method). If @a 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. - * 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 <masks_to_be_added> to the <event_handler>'s entry. - /// <event_handler> must already have been registered. - virtual int schedule_wakeup (ACE_Event_Handler *event_handler, - ACE_Reactor_Mask masks_to_be_added); - - /// Add <masks_to_be_added> to the <handle>'s entry. <event_handler> - /// associated with <handle> must already have been registered. - virtual int schedule_wakeup (ACE_HANDLE handle, - ACE_Reactor_Mask masks_to_be_added); - - /// Clear <masks_to_be_cleared> from the <event_handler>'s entry. - virtual int cancel_wakeup (ACE_Event_Handler *event_handler, - ACE_Reactor_Mask masks_to_be_cleared); - - /// Clear <masks_to_be_cleared> from the <handle>'s entry. - virtual int cancel_wakeup (ACE_HANDLE handle, - ACE_Reactor_Mask masks_to_be_cleared); - - // = Notification methods. - - /** - * Notify <event_handler> of <mask> event. The <ACE_Time_Value> - * indicates how long to blocking trying to notify. If <timeout> == - * 0, the caller will block until action is possible, else will wait - * until the relative time specified in <timeout> elapses). - */ - virtual int notify (ACE_Event_Handler *event_handler = 0, - ACE_Reactor_Mask mask = ACE_Event_Handler::EXCEPT_MASK, - ACE_Time_Value * = 0); - - /** - * Set the maximum number of times that ACE_Reactor_Impl will - * iterate and dispatch the <ACE_Event_Handlers> that are passed in - * via the notify queue before breaking out of its - * <ACE_Message_Queue::dequeue> loop. By default, this is set to - * -1, which means "iterate until the queue is empty." Setting this - * to a value like "1 or 2" will increase "fairness" (and thus - * prevent starvation) at the expense of slightly higher dispatching - * overhead. - */ - virtual void max_notify_iterations (int); - - /** - * Get the maximum number of times that the ACE_Reactor_Impl will - * iterate and dispatch the <ACE_Event_Handlers> that are passed in - * via the notify queue before breaking out of its - * <ACE_Message_Queue::dequeue> loop. - */ - virtual int max_notify_iterations (void); - - /** - * Purge any notifications pending in this reactor for the specified - * ACE_Event_Handler object. Returns the number of notifications - * purged. Returns -1 on error. - */ - virtual int purge_pending_notifications (ACE_Event_Handler * = 0, - ACE_Reactor_Mask = ACE_Event_Handler::ALL_EVENTS_MASK); - - /** - * Return the Event_Handler associated with <handle>. Return 0 if - * <handle> is not registered. - */ - virtual ACE_Event_Handler *find_handler (ACE_HANDLE handle); - - /** - * Check to see if <handle> is associated with a valid Event_Handler - * bound to <mask>. Return the <event_handler> associated with this - * <handler> if <event_handler> != 0. - */ - virtual int handler (ACE_HANDLE handle, - ACE_Reactor_Mask mask, - ACE_Event_Handler **event_handler = 0); - - /** - * Check to see if <signum> is associated with a valid Event_Handler - * bound to a signal. Return the <event_handler> associated with - * this <handler> if <event_handler> != 0. - */ - virtual int handler (int signum, - ACE_Event_Handler ** = 0); - - /// Returns true if Reactor has been successfully initialized, else - /// false. - virtual int initialized (void); - - /// Returns the current size of the Reactor's internal descriptor - /// table. - virtual size_t size (void) const; - - /// Returns a reference to the Reactor's internal lock. - virtual ACE_Lock &lock (void); - - /// Wake up all threads waiting in the event loop. - virtual void wakeup_all_threads (void); - - /// Transfers ownership of Reactor_Impl to the new_owner. - /** - * @note There is no need to set the owner of the event loop for the - * ACE_Dev_Poll_Reactor. Multiple threads may invoke the - * event loop simulataneously. As such, this method is a - * no-op. - */ - virtual int owner (ACE_thread_t new_owner, ACE_thread_t *old_owner = 0); - - /// Return the ID of the "owner" thread. - /** - * @note There is no need to set the owner of the event loop for the - * ACE_Dev_Poll_Reactor. Multiple threads may invoke the - * event loop simulataneously. As such, this method is a - * no-op. - */ - virtual int owner (ACE_thread_t *owner); - - /// Get the existing restart value. - virtual int restart (void); - - /// Set a new value for restart and return the original value. - /** - * @param r If zero, then the event loop will not be automatically - * restarted if the underlying poll is interrupted via the - * INTR (interrupt) signal. - * - * @return Returns the previous "restart" value. - */ - virtual int restart (int r); - - /// Set position of the owner thread. - /** - * @note This is currently a no-op. - */ - virtual void requeue_position (int); - - /// Get position of the owner thread. - /** - * @note This is currently a no-op. - */ - virtual int requeue_position (void); - - /** - * @name Low-level wait_set mask manipulation methods - * - * Low-level methods to manipulate the event/reactor mask associated - * with a handle and event handler when polling for events. - * @par - * The "interest set," i.e. the wait set, can be directly - * manipulated with these methods. - */ - //@{ - - /// GET/SET/ADD/CLR the dispatch mask "bit" bound with the - /// event_handler and mask. - /** - * @return Old mask on success, -1 on error. - */ - virtual int mask_ops (ACE_Event_Handler *event_handler, - ACE_Reactor_Mask mask, - int ops); - - /// GET/SET/ADD/CLR the dispatch MASK "bit" bound with the handle - /// and mask. - /** - * @return Old mask on success, -1 on error. - */ - virtual int mask_ops (ACE_HANDLE handle, - ACE_Reactor_Mask mask, - int ops); - - //@} - - /** - * @name Low-level ready_set mask manipulation methods - * - * These methods are unimplemented. - */ - //@{ - - /// GET/SET/ADD/CLR the ready "bit" bound with the event_handler - /// and mask. - virtual int ready_ops (ACE_Event_Handler *event_handler, - ACE_Reactor_Mask mask, - int ops); - - /// GET/SET/ADD/CLR the ready "bit" bound with the handle and mask. - virtual int ready_ops (ACE_HANDLE handle, - ACE_Reactor_Mask, - int ops); - - //@} - - /// Dump the state of an object. - virtual void dump (void) const; - - /// Declare the dynamic allocation hooks. - ACE_ALLOC_HOOK_DECLARE; - -protected: - - class Token_Guard; - - /// Non-locking version of wait_pending(). - /** - * 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". - * - * @note It is only possible to achieve millisecond timeout - * resolutions with the ACE_Dev_Poll_Reactor. - */ - int work_pending_i (ACE_Time_Value *max_wait_time); - - /// Poll for events and return the number of event handlers that - /// were dispatched. - /** - * This is a helper method called by all handle_events() methods. - */ - int handle_events_i (ACE_Time_Value *max_wait_time, Token_Guard &guard); - - /// Perform the upcall with the given event handler method. - int upcall (ACE_Event_Handler *event_handler, - int (ACE_Event_Handler::*callback)(ACE_HANDLE), - ACE_HANDLE handle); - - /** - * Dispatch ACE_Event_Handlers for time events, I/O events, and - * signal events. Returns the total number of ACE_Event_Handlers - * that were dispatched or -1 if something goes wrong. - */ - int dispatch (Token_Guard &guard); - - /// Dispatch a single timer, if ready. - /// Returns: 0 if no timers ready (token still held), - /// 1 if a timer was expired (token released), - /// -1 on error (token still held). - int dispatch_timer_handler (Token_Guard &guard); - - /// Dispatch an IO event to the corresponding event handler. Returns - /// Returns: 0 if no events ready (token still held), - /// 1 if an event was expired (token released), - /// -1 on error (token still held). - int dispatch_io_event (Token_Guard &guard); - - /// Register the given event handler with the reactor. - int register_handler_i (ACE_HANDLE handle, - ACE_Event_Handler *eh, - ACE_Reactor_Mask mask); - - /// Remove the event handler associated with the given handle and - /// event mask from the "interest set." - int remove_handler_i (ACE_HANDLE handle, ACE_Reactor_Mask mask); - - /// Temporarily remove the given handle from the "interest set." - int suspend_handler_i (ACE_HANDLE handle); - - /// Place the given handle that was temporarily removed from the - /// "interest set," i.e that was suspended, back in to the interest - /// set. The given handle will once again be polled for events. - int resume_handler_i (ACE_HANDLE handle); - - /// GET/SET/ADD/CLR the dispatch MASK "bit" bound with the handle - /// and mask. This internal helper method acquires no lock. - /** - * @return Old mask on success, -1 on error. - */ - int mask_ops_i (ACE_HANDLE handle, - ACE_Reactor_Mask mask, - int ops); - - /// Convert a reactor mask to its corresponding poll() event mask. - short reactor_mask_to_poll_event (ACE_Reactor_Mask mask); - -protected: - - /// Has the reactor been initialized. - bool initialized_; - - /// The file descriptor associated with the open `/dev/poll' or - /// `/dev/epoll' device. - /** - * All interactions with the `/dev/poll' or `/dev/epoll' device are - * done through this file descriptor. - */ - ACE_HANDLE poll_fd_; - - /// The maximum number of file descriptors over which demultiplexing - /// will occur. - size_t size_; - - /// Track HANDLES we are interested in for various events that must - /// be dispatched *without* polling. - /// ACE_Dev_Poll_Ready_Set ready_set_; - -#if defined (ACE_HAS_EVENT_POLL) - /// Table of event structures to be filled by epoll_wait: - struct epoll_event *events_; - - /// Pointer to the next epoll_event array element that contains the next - /// event to be dispatched. - struct epoll_event *start_pevents_; - - /// The last element in the event array plus one. - /** - * The loop that dispatches IO events stops when this->start_pevents_ == - * this->end_pevents_. - */ - struct epoll_event *end_pevents_; - -#else - /// The pollfd array that `/dev/poll' will feed its results to. - struct pollfd *dp_fds_; - - - /// Pointer to the next pollfd array element that contains the next - /// event to be dispatched. - struct pollfd *start_pfds_; - - /// The last element in the pollfd array plus one. - /** - * The loop that dispatches IO events stops when this->start_pfds == - * this->end_pfds_. - */ - struct pollfd *end_pfds_; -#endif /* ACE_HAS_EVENT_POLL */ - - /// This flag is used to keep track of whether we are actively handling - /// events or not. - sig_atomic_t deactivated_; - - /// Lock used for synchronization of reactor state. - ACE_Dev_Poll_Reactor_Token token_; - - /// Adapter used to return internal lock to outside world. - ACE_Lock_Adapter<ACE_Dev_Poll_Reactor_Token> lock_adapter_; - - /// The repository that contains all registered event handlers. - ACE_Dev_Poll_Reactor_Handler_Repository handler_rep_; - - /// Defined as a pointer to allow overriding by derived classes... - ACE_Timer_Queue *timer_queue_; - - /// Keeps track of whether we should delete the timer queue (if we - /// didn't create it, then we don't delete it). - int delete_timer_queue_; - - /// Handle signals without requiring global/static variables. - ACE_Sig_Handler *signal_handler_; - - /// Keeps track of whether we should delete the signal handler (if we - /// didn't create it, then we don't delete it). - int delete_signal_handler_; - - /// Callback object that unblocks the <ACE_Select_Reactor> if it's - /// sleeping. - ACE_Reactor_Notify *notify_handler_; - - /// Keeps track of whether we need to delete the notify handler (if - /// we didn't create it, then we don't delete it). - int delete_notify_handler_; - - /// Flag that determines if signals are masked during event - /// dispatching. - /** - * If 0 then the Reactor will not mask the signals during the event - * dispatching. This is useful for applications that do not - * register any signal handlers and want to reduce the overhead - * introduce by the kernel level locks required to change the mask. - */ - int mask_signals_; - - /// Restart the handle_events event loop method automatically when - /// polling function in use (ioctl() in this case) is interrupted - /// via an EINTR signal. - int restart_; - -protected: - - /** - * @class Token_Guard - * - * @brief A helper class that helps grabbing, releasing and waiting - * on tokens for a thread that needs access to the reactor's token. - */ - class Token_Guard - { - public: - - /// Constructor that will grab the token for us - Token_Guard (ACE_Dev_Poll_Reactor_Token &token); - - /// Destructor. This will release the token if it hasn't been - /// released till this point - ~Token_Guard (void); - - /// Release the token .. - void release_token (void); - - /// Returns whether the thread that created this object owns the - /// token or not. - int is_owner (void); - - /// A helper method that acquires the token 1) at a low priority, and - /// 2) wait quietly for the token, not waking another thread. This - /// is appropriate for cases where a thread wants to wait for and - /// dispatch an event, not causing an existing waiter to relinquish the - /// token, and also queueing up behind other threads waiting to modify - /// event records. - int acquire_quietly (ACE_Time_Value *max_wait = 0); - - /// A helper method that acquires the token at a high priority, and - /// does wake the current token holder. - int acquire (ACE_Time_Value *max_wait = 0); - - private: - - Token_Guard (void); - - private: - - /// The Reactor token. - ACE_Dev_Poll_Reactor_Token &token_; - - /// Flag that indicate whether the thread that created this object - /// owns the token or not. A value of 0 indicates that this class - /// hasn't got the token (and hence the thread) and a value of 1 - /// vice-versa. - int owner_; - - }; - -}; - - -/** - * @class ACE_Dev_Poll_Handler_Guard - * - * @brief Class used to make event handler reference count - * manipulation exception-safe. - * - * This class makes the reference count manipulation that occurs - * during an upcall exception-safe. Prior to dispatching the event - * handler, the reference count is increased. Once the upcall for the - * given event handler is complete, its reference count will be decreased. - */ -class ACE_Dev_Poll_Handler_Guard -{ -public: - - /// Constructor - /** - * The constructor checks to see if @a eh is a reference-counted handler and - * remember that for later. If @a eh is reference counted, its reference - * count is incremented unless @a do_incr is false. - * @a do_incr should be false if the reference count was incremented - * independently of this guard, for example, on a notify handler since - * the reference count is incremented when the notify is queued. - */ - ACE_Dev_Poll_Handler_Guard (ACE_Event_Handler *eh, bool do_incr = true); - - /// Destructor - /** - * The destructor decrements the reference count on the event - * handler corresponding to the given handle. - */ - ~ACE_Dev_Poll_Handler_Guard (void); - - /// Release the event handler from this guard; when the destructor is - /// called, the handler's reference count will not be decremented. - void release (void); - -private: - - /// The event handler being managed. - ACE_Event_Handler *eh_; - - /// true if eh_ is a reference-counted handler. - bool refcounted_; - -}; - -ACE_END_VERSIONED_NAMESPACE_DECL - -#if defined (__ACE_INLINE__) -# include "ace/Dev_Poll_Reactor.inl" -#endif /* __ACE_INLINE__ */ - -#endif /* ACE_HAS_EVENT_POLL || ACE_HAS_DEV_POLL */ - -#include /**/ "ace/post.h" - -#endif /* ACE_DEV_POLL_REACTOR_H */ |