X-Git-Url: https://git.llucax.com/software/eventxx.git/blobdiff_plain/7ed68f0ab7e9b4e01141e5b8947f236c7e83fe77..e3b857433641f21c26dcac5705bd6bf6cab90175:/eventxx diff --git a/eventxx b/eventxx index 4405fb8..6bf3f9b 100644 --- a/eventxx +++ b/eventxx @@ -94,7 +94,7 @@ * eventxx::dispatcher& d; * int i; * handler(eventxx::dispatcher& d): d(d), i(0) {} - * void operator() (int signum, short event) + * void operator() (int signum, eventxx::type event) * { * if (i < 5) std::cout << "keep going...\n"; * else @@ -130,35 +130,33 @@ * * @section Status * - * This library has not been widely used yet, so it lacks proper testing. - * Because templates are not even compiled when they are not used, don't have to - * be surprised if you catch a piece of code that doesn't compile. The library - * has no support for buffered events yet. It doesn't support the HTTP stuff, - * and probably never will because that has nothing to do with event handling. - * - * If you notice that when using @eventxx your program leaks some memory, don't - * blame me, blame @libevent :) @libevent has a known bug on @c event_base_free() - * that makes it assert always, so @c event_base_free() is unusable, unless you - * patch your libevent (for example, using this patch - * written by Mark D. Anderson, and who knows why it's not still applied). If - * you do so, you can compile your programs with @c -DEVENT_BASE_FREE_FIX so - * @c event_base_free() gets called in the eventxx::dispatcher @link - * eventxx::dispatcher::~dispatcher() destructor @endlink. - * - * That said, I think it's still pretty usable anyways. If something is broken - * it would be really easy to fix because @eventxx is just a simple wrapper - * around @libevent. So, please try it out, and if you have any problems, - * drop me an + * This library has not been widely used yet, but it's used in some serious + * projects, so I think it's moderately stable now. The library has no support + * for buffered events yet, but patches are welcome. It doesn't support the + * HTTP stuff, and probably never will because that has nothing to do with + * event handling. + * + * @libevent had a memory leak before version 1.3b (before 1.2 it didn't even + * had a way free that memory, from version 1.2 to 1.3a, if you tried to free the + * memory the program abort() because a failed assertion). Because of that, + * there is a way to disable the @link eventxx::dispatcher::~dispatcher() + * destructor @endlink (which calls the inexistent/broken @c event_base_free() + * function). So if you use a @libevent version previous to 1.3b, you have to + * compile your programs defining the EVENTXX_NO_EVENT_BASE_FREE macro. + * + * If something is broken it would be really easy to fix because @eventxx is + * just a simple wrapper around @libevent. So, please try it out, and if you + * have any problems, drop me an * e-mail and and I'll fix it ASAP (or provide a patch and you will be my * best friend ;). * - * Patches to support buffered events are welcome too. - * + * If you use this library, please drop me an e-mail with your thoughts, or + * simply saying "I use it", so I can keep track of how many people really use + * it. * * @author Leandro Lucarella * - * @version 0.1 + * @version 0.6 * * @par License * This program is under the BOLA license (see @@ -180,6 +178,12 @@ * callbacks. */ +/** @example wrapped-functor-way.cpp + * + * This is a simple example illustrating the usage with an arbitrary member + * function as an event handler callbacks. + */ + /** @example mixed-way.cpp * * This is a simple example illustrating the usage with a mix of C-like callbacks @@ -313,10 +317,6 @@ enum }; -/// C function used as callback in the C API. -typedef void (*ccallback_type)(int, short, void*); - - /** * Time used for timeout values. * @@ -373,6 +373,12 @@ struct time: ::timeval * function objects (see eventxx::event, eventxx::timer and eventxx::signal * templates). The former are just typedef'ed specialization of the later. * + * A member function wrapper functor (eventxx::mem_cb) is also included, + * so you can use any member function (method) as an event handler. + * + * Please note that C-like function callback take a short as the type of event, + * while functors (or member functions) use eventxx::type. + * * All events derive from a plain class (not template) eventxx::basic_event, one * of the main utilities of it (besides containing common code ;) is to be used * in STL containers. @@ -381,6 +387,11 @@ struct time: ::timeval */ //@{ + +/// C function used as callback in the C API. +typedef void (*ccallback_type)(int, short, void*); + + /** * Type of events. * @@ -401,6 +412,14 @@ enum type PERSIST = EV_PERSIST ///< Not really an event, is an event modifier. }; +inline +type operator| (const type& t1, const type& t2) +{ + int r = static_cast< int >(t1) | static_cast< int >(t2); + return *reinterpret_cast< type* >(&r); +} + + /** * Basic event from which all events derive. * @@ -503,9 +522,9 @@ struct event: basic_event * @param ev Type of events to monitor (see eventxx::type). * @param handler Callback functor. */ - event(int fd, short ev, F& handler) throw() + event(int fd, type ev, F& handler) throw() { - event_set(this, fd, ev, &wrapper, + event_set(this, fd, static_cast< short >(ev), &wrapper, reinterpret_cast< void* >(&handler)); } @@ -539,9 +558,9 @@ struct event< ccallback_type >: basic_event * @param handler C-style callback function. * @param arg Arbitrary pointer to pass to the handler as argument. */ - event(int fd, short ev, ccallback_type handler, void* arg = 0) throw() + event(int fd, type ev, ccallback_type handler, void* arg = 0) throw() { - event_set(this, fd, ev, handler, arg); + event_set(this, fd, static_cast< short >(ev), handler, arg); } protected: @@ -689,6 +708,41 @@ typedef eventxx::timer< ccallback_type > ctimer; /// Shortcut to C-style signal handler. typedef eventxx::signal< ccallback_type > csignal; +/** + * Helper functor to use an arbitrary member function as an event handler. + * + * With this wrapper, you can use any object method, which accepts the right + * parameters (int, short) and returns void, as an event handler. This way you + * don't have to overload the operator() which can be confusing depending on the + * context. + * + * You can see an usage example in the Examples Section. + */ +template < typename O, typename M > +struct mem_cb +{ + + /** + * Member function callback constructor. + * + * It expects to receive a class as the first parameter (O), and a + * member function (of that class O) as the second parameter. + * + * When this instance is called with fd and ev as function arguments, + * object.method(fd, ev) will be called. + * + * @param object Object to be used. + * @param method Method to be called. + */ + mem_cb(O& object, M method) throw(): + _object(object), _method(method) {} + + void operator() (int fd, type ev) { (_object.*_method)(fd, ev); } + protected: + O& _object; + M _method; + +}; // struct mem_cb //@} @@ -735,15 +789,9 @@ struct dispatcher internal::event_base_priority_init(_event_base, npriorities); } -#ifdef EVENT_BASE_FREE_FIX +#ifndef EVENTXX_NO_EVENT_BASE_FREE /// Free dispatcher resources, see @ref Status section for details. ~dispatcher() throw() { event_base_free(_event_base); } -#else -#warning "The dispatcher class *will* leak memory because of a libevent bug, " \ - "see http://www.mail-archive.com/libevent-users@monkey.org/msg00110.html " \ - "for more info an a patch. If you already have this patch, please " \ - "-DEVENT_BASE_FREE_FIX to your compiler to make this message disappear " \ - "and really free the dispatcher memory using event_base_free()." #endif /** @@ -797,8 +845,9 @@ struct dispatcher template < typename F > void add_once(int fd, type ev, F& handler) { - internal::event_once(fd, ev, &dispatcher::wrapper< F >, - reinterpret_cast< void* >(&handler), 0); + internal::event_once(fd, static_cast< short>(ev), + &dispatcher::wrapper< F >, + reinterpret_cast< void* >(&handler), 0); } /** @@ -814,7 +863,8 @@ struct dispatcher */ void add_once(int fd, type ev, ccallback_type handler, void* arg) { - internal::event_once(fd, ev, handler, arg, 0); + internal::event_once(fd, static_cast< short >(ev), handler, + arg, 0); } /** @@ -831,10 +881,11 @@ struct dispatcher template < typename F > void add_once(int fd, type ev, F& handler, const time& to) { - internal::event_once(fd, ev, &dispatcher::wrapper< F >, - reinterpret_cast< void* >(&handler), - // XXX HACK libevent don't use const - const_cast< time* >(&to)); + internal::event_once(fd, static_cast< short >(ev), + &dispatcher::wrapper< F >, + reinterpret_cast< void* >(&handler), + // XXX HACK libevent don't use const + const_cast< time* >(&to)); } /** @@ -852,7 +903,7 @@ struct dispatcher void add_once(int fd, type ev, ccallback_type handler, void* arg, const time& to) { - internal::event_once(fd, ev, handler, arg, + internal::event_once(fd, static_cast< short >(ev), handler, arg, // XXX HACK libevent don't use const const_cast< time* >(&to)); } @@ -920,10 +971,12 @@ struct dispatcher * processed, if eventxx::NONBLOCK is specified, then this * function returns even if there are no pending events. * - * @return Not very well specified by @libevent :-/ that's why it - * doesn't throw an exception either. + * @return 0 if eventxx::NONBLOCK or eventxx::ONCE is set, 1 if there + * are no more events registered and EINTR if you use the + * @libevent's @c event_gotsig and return -1 in your + * @c event_sigcb callback. */ - int dispatch(int flags = 0) throw() // TODO throw(exception) + int dispatch(int flags = 0) throw() { return internal::event_base_loop(_event_base, flags); } @@ -947,7 +1000,7 @@ struct dispatcher protected: internal::event_base* _event_base; template < typename F > - static void wrapper(int fd, type ev, void* h) + static void wrapper(int fd, short ev, void* h) { F& handler = *reinterpret_cast< F* >(h); handler(fd, *reinterpret_cast< type* >(&ev)); @@ -955,8 +1008,7 @@ struct dispatcher }; // struct dispatcher - -} // namespace event +} // namespace eventxx #endif // _EVENTXX_HPP_