X-Git-Url: https://git.llucax.com/software/eventxx.git/blobdiff_plain/e025da92de4fc21c84f30117de2bed7f3c579fb2..f96e870a834c80bffa69ff1395ff35e263d65861:/eventxx?ds=inline diff --git a/eventxx b/eventxx index 5d13b3e..dc0a479 100644 --- a/eventxx +++ b/eventxx @@ -9,37 +9,27 @@ * * @section Introduction * - * The libevent API provides - * a mechanism to execute a callback function when a specific event occurs on - * a file descriptor or after a timeout has been reached. Furthermore, libevent - * also support callbacks due to signals or regular timeouts. - * - * libevent is meant to replace the event loop found in event driven network - * servers. An application just needs to call dispatcher::dispatch() and then - * add or remove events dynamically without having to change the event loop. - * - * Currently, libevent supports /dev/poll, kqueue(2), select(2), poll(2) and - * epoll(4). It also has experimental support for real-time signals. The - * internal event mechanism is completely independent of the exposed event API, - * and a simple update of libevent can provide new functionality without having - * to redesign the applications. As a result, Libevent allows for portable - * application development and provides the most scalable event notification - * mechanism available on an operating system. Libevent should compile on Linux, - * *BSD, Mac OS X, Solaris and Windows. - * - * This is a simple, direct, one-header inline C++ wrapper for libevent. Yes, - * it's just one header file, so if you want to use it you can just copy the - * file to your project and you are set. - * - * It's designed to be as close to use to libevent (without compromising modern - * C++ programming techniques) and efficiency (since all implementation is - * trivial and inline, theoretically, it imposes no overhead at all). - * - * Please, visit the eventxx - * website for the latest documentation. - * - * You can always get the - * current + * @libevent is a popular API that provides a mechanism to execute a callback + * function when a specific event occurs on a file descriptor or after a + * timeout has been reached. Furthermore, @libevent also support callbacks due + * to signals or regular timeouts. + * + * @eventxx is a simple, direct, one-header inline C++ wrapper for @libevent. + * Yes, it's just one header file, so if you want to use it you can just copy + * the file to your project and you are set (well, you'll need to link to + * @libevent too ;). I know @eventxx will work with @libevent 1.1 and 1.2 if you + * use the @c event_base_free() fix (see \ref Status section for more details). + * + * It's designed to be as close to use to @libevent (without compromising + * modern C++ programming techniques) and efficient (since all implementation + * is trivial and inline, theoretically, it imposes no overhead at all) as + * possible. + * + * Please, visit the @eventxx website for the latest version of this + * documentation. + * + * You can always get the current * release from the * release * directory or grab the @@ -49,40 +39,48 @@ * You can also take a look the the darcsweb interface to see * the latest - * changes online. + * changes online or subscribe to its + * RSS + * feed to follow the development. * * * @section Usage * - * This wrapper was designed to be used just like libevent, but with C++ style + * You probably should read @libevent documentation to get started or at least + * just for reference, although @eventxx is pretty simple so you can jump right + * into the \ref Example section (or the example list) and write a working + * program without much trouble. + * + * This wrapper was designed to be used just like @libevent, but with C++ style * syntax sugar (or poison, depends on your point of view ;) and goodies. The * main difference to libevent is you always have to instance a * eventxx::dispatcher to get an event loop. There is no implicit global event * loop. This adds just an extra line of code for single threaded applications - * and makes things much more simple. See eventxx::dispatcher documentation for - * more details. + * and makes things much more simpler, so I hope nobody complains about it ;). + * See eventxx::dispatcher documentation for more details. * - * You can use use the same plain functions callbacks or the other kind of - * function objects (see @link events @endlink section for details on event + * You can use use the same plain functions callbacks @libevent use or the other + * kind of function objects (see @ref events section for details on event * types). * - * eventxx uses @link exceptions @endlink to report errors. All functions has - * exception specifications, so it's easy to find out what to expect. See - * exceptions section for more detail. + * @eventxx uses @ref exceptions to report errors. All functions have exception + * specifications, so it's easy to find out what to expect. See @ref exceptions + * section for more detail. * - * A timespec abstraction is provided in eventxx::time for convenient argument - * passing. Even more, it's a timespec itself, with some convenient methods for - * accessing the timespec attributes in a more C++ way. And even more, eventxx - * is such a direct mapping that all eventxx::event's are libevent event structs - * too, so theoretically you can pass a eventxx::event to libevent C functions - * without much trouble. eventxx::dispatcher is the only class that is not - * derived from libevent struct (event_base) because this struct it's not - * defined on the libevent header (just declared). + * A @c timespec abstraction is provided as eventxx::time for convenient + * argument passing. Even more, it's a @c timespec itself, with some convenient + * methods for accessing the attributes with pritier names. And even more, + * @eventxx is such a direct mapping that all eventxx::event's are @libevent + * event structs too, so theoretically you can pass a eventxx::event to + * @libevent C functions without much trouble. eventxx::dispatcher is the only + * class that is not derived from @libevent struct (@c event_base) because this + * struct it's not defined on the libevent header (just declared). * * Maybe you shouldn't know this implementation details to keep the abstraction, * but this is a basic design goal of this wrapper so there is not much chance - * that this changes in the future (but use this knowledge with care, you are - * warned ;). + * that this changes in the future (but use this knowledge with care, you have + * been warned ;). + * * * @section Example * @@ -126,31 +124,31 @@ * } * @endcode * - * You can see some more examples on the test directory of the distribution or - * on the examples related page. + * You can see more examples on the test directory of the distribution or on the + * examples related page. * * * @section Status * - * This library was not widely used yet, it lack some testing. Because templates - * are not even compiled when they are used, you can't be surprised if you catch - * a piece of code that didn't got even compiled yet because the lack of - * testing. The library has no support for buffered events yet either. It - * doesn't support the http stuff, and probably never will because that has - * nothing to do with event handling. - * - * If you notice this lib leaks memory, don't blame me, blame libevent :) - * libevent has a known bug on event_base_free() that makes it assert always, so - * event_base_free() it's 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 -DEVENT_BASE_FREE_FIX so - * event_base_free() gets called. + * 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. * - * That said, I think it's pretty usable anyways. If something is broken it - * would be really easy to fix it because is just a simple wrapper around - * libevent. So, please try it out, and if you have any problems, + * 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 * e-mail and and I'll fix it ASAP (or provide a patch and you will be my * best friend ;). @@ -164,9 +162,9 @@ * * @par License * This program is under the BOLA license (see - * http://auriga.wearlab.de/~alb/bola/ for more info or the + * http://auriga.wearlab.de/~alb/bola/ for more details or read the * LICENSE - * file itself). + * file itself, it's very short and it basically says it's Public Domain). * */ @@ -489,8 +487,8 @@ struct basic_event: internal::event * an integer (the file descriptor of the fired event) and an event::type (the * type of event being fired). * There is a specialized version of this class which takes as the template - * parameter a C function with the ccallback_type signature, just like C - * libevent API does. + * parameter a C function with the eventxx::ccallback_type signature, just like + * C @libevent API does. * * @see eventxx::event< ccallback_type > */ @@ -541,7 +539,7 @@ 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) throw() + event(int fd, short ev, ccallback_type handler, void* arg = 0) throw() { event_set(this, fd, ev, handler, arg); } @@ -598,7 +596,7 @@ struct timer< ccallback_type >: event< ccallback_type > * @param handler C-style callback function. * @param arg Arbitrary pointer to pass to the handler as argument. */ - timer(ccallback_type handler, void* arg) throw() + timer(ccallback_type handler, void* arg = 0) throw() { evtimer_set(this, handler, arg); } @@ -664,7 +662,7 @@ struct signal< ccallback_type >: event< ccallback_type > * @param handler C-style callback function. * @param arg Arbitrary pointer to pass to the handler as argument. */ - signal(int signum, ccallback_type handler, void* arg) throw() + signal(int signum, ccallback_type handler, void* arg = 0) throw() { signal_set(this, signum, handler, arg); } @@ -719,7 +717,8 @@ struct dispatcher */ dispatcher() throw() { - _event_base = static_cast< internal::event_base* >(internal::event_init()); + _event_base = static_cast< internal::event_base* >( + internal::event_init()); } /** @@ -729,16 +728,22 @@ struct dispatcher */ dispatcher(int npriorities) throw(std::bad_alloc) { - _event_base = static_cast< internal::event_base* >(internal::event_init()); + _event_base = static_cast< internal::event_base* >( + internal::event_init()); if (!_event_base) throw std::bad_alloc(); // Can't fail because there is no way that it has active events internal::event_base_priority_init(_event_base, npriorities); } #ifdef EVENT_BASE_FREE_FIX + /// 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()." +#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 /** @@ -775,7 +780,8 @@ struct dispatcher if (priority != DEFAULT_PRIORITY && internal::event_priority_set(&e, priority)) throw invalid_priority(); - internal::event_add(&e, const_cast< time* >(&to)); // XXX HACK libevent don't use const + // XXX HACK libevent don't use const + internal::event_add(&e, const_cast< time* >(&to)); } /** @@ -827,7 +833,8 @@ struct dispatcher { internal::event_once(fd, ev, &dispatcher::wrapper< F >, reinterpret_cast< void* >(&handler), - const_cast< time* >(&to)); // XXX HACK libevent don't use const + // XXX HACK libevent don't use const + const_cast< time* >(&to)); } /** @@ -842,9 +849,12 @@ struct dispatcher * @param arg Arbitrary pointer to pass to the handler as argument. * @param to Timeout. */ - void add_once(int fd, type ev, ccallback_type handler, void* arg, const time& to) + void add_once(int fd, type ev, ccallback_type handler, void* arg, + const time& to) { - internal::event_once(fd, ev, handler, arg, const_cast< time* >(&to)); // XXX HACK libevent don't use const + internal::event_once(fd, ev, handler, arg, + // XXX HACK libevent don't use const + const_cast< time* >(&to)); } /** @@ -861,7 +871,8 @@ struct dispatcher { internal::event_once(-1, EV_TIMEOUT, &dispatcher::wrapper< F >, reinterpret_cast< void* >(&handler), - const_cast< time* >(&to)); // XXX HACK libevent don't use const + // XXX HACK libevent don't use const + const_cast< time* >(&to)); } /** @@ -876,7 +887,9 @@ struct dispatcher */ void add_once_timer(ccallback_type handler, void* arg, const time& to) { - internal::event_once(-1, EV_TIMEOUT, handler, arg, const_cast< time* >(&to)); // XXX HACK libevent don't use const + // XXX HACK libevent don't use const + internal::event_once(-1, EV_TIMEOUT, handler, arg, + const_cast< time* >(&to)); } /** @@ -906,8 +919,13 @@ struct dispatcher * @param flags If eventxx::ONCE is specified, then just one event is * processed, if eventxx::NONBLOCK is specified, then this * function returns even if there are no pending events. + * + * @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) // TODO throw(exception) + int dispatch(int flags = 0) throw() { return internal::event_base_loop(_event_base, flags); } @@ -917,8 +935,11 @@ struct dispatcher * * @param to If a timeout is given, the loop exits after the specified * time is elapsed. + * + * @return Not very well specified by @libevent :-/ that's why it + * doesn't throw an exception either. */ - int exit(const time& to = time()) + int exit(const time& to = time()) throw() // TODO throw(exception) { // XXX HACK libevent don't use const return internal::event_base_loopexit(_event_base,