Fix inifinite recursion when using operator| for eventxx::type.

[software/eventxx.git] / eventxx

diff --git a/eventxx b/eventxx
index 080f40c3c5251fdbeb2f8e8fb54f04430781e216..c5f13d1480f8a41c4cb05af1d7ac767ea7cb3410 100644 (file)
--- a/eventxx
+++ b/eventxx
@@ -1,7 +1,7 @@
 #ifndef _EVENTXX_HPP_
 #define _EVENTXX_HPP_
 
 #ifndef _EVENTXX_HPP_
 #define _EVENTXX_HPP_
 

-#include <sys/types.h> // timeval (hack -> event.h don't include it)
+#include <sys/types.h> // timeval

 #include <stdexcept>   // std::exception, std::invalid_argument,
                        // std::runtime_error, std::bad_alloc
 
 #include <stdexcept>   // std::exception, std::invalid_argument,
                        // std::runtime_error, std::bad_alloc
 


@@ -9,42 +9,218 @@
  *
  * @section Introduction
  *
  *
  * @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 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.

  *
  *

- * 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.
+ * @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).

  *
  *

- * 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. 
+ * 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.

  *
  *

- * This is a simple, direct, one-header inline C++ wrapper for libevent.
- * 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 version of this
+ * documentation.
+ *
+ * You can always get the <a
+ * href="http://www.llucax.com.ar/~luca/eventxx/releases/eventxx.tar.gz">current
+ * release</a> from the
+ * <a href="http://www.llucax.com.ar/~luca/eventxx/releases/">release
+ * directory</a> or grab the
+ * <a href="http://www.llucax.com.ar/~luca/repos/eventxx/">most up to date
+ * sources</a> from the <a href="http://www.darcs.net/">darcs</a> repository.
+ *
+ * You can also take a look the the <a
+ * href="http://auriga.wearlab.de/~alb/darcsweb/">darcsweb</a> interface to see
+ * the <a href="http://www.llucax.com.ar/~luca/repos/darcsweb/?r=eventxx">latest
+ * changes online</a> or subscribe to its
+ * <a href="http://www.llucax.com.ar/~luca/repos/darcsweb/?r=eventxx;a=rss">RSS
+ * feed</a> to follow the development.

  *
  *
  * @section Usage
  *
  *
  *
  * @section Usage
  *

- * The best way to explain how this works is by examples. TODO
+ * 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 simpler, so I hope nobody complains about it ;).
+ * See eventxx::dispatcher documentation for more details.
+ *
+ * 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 @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 @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 have
+ * been  warned ;).
+ *
+ *
+ * @section Example
+ *
+ * @code
+ * #include <eventxx>
+ * #include <iostream>
+ * #include <csignal>
+ *
+ * struct handler
+ * {
+ *     eventxx::dispatcher& d;
+ *     int i;
+ *     handler(eventxx::dispatcher& d): d(d), i(0) {}
+ *     void operator() (int signum, eventxx::type event)
+ *     {
+ *             if (i < 5) std::cout << "keep going...\n";
+ *             else
+ *             {
+ *                     std::cout << "done!\n";
+ *                     d.exit();
+ *             }
+ *     }
+ * };
+ *
+ * void sighandler(int signum, short event, void* data)
+ * {
+ *     int& i = *static_cast< int* >(data);
+ *     std::cout << ++i << " interrupts, ";
+ * }
+ *
+ * int main()
+ * {
+ *     eventxx::dispatcher d;
+ *     handler h(d);
+ *     eventxx::csignal sigev(SIGINT, sighandler, &h.i);
+ *     eventxx::signal< handler > e(SIGINT, h);
+ *     d.add(sigev);
+ *     d.add(e);
+ *     d.dispatch();
+ *     return 0;
+ * }
+ * @endcode
+ *
+ * You can see more examples on the test directory of the distribution or on the
+ * examples related page.
+ *
+ *
+ * @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 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 <a
+ * href="http://monkeymail.org/archives/libevent-users/2006-April/000141.html">patch</a>
+ * 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,
+ * <a href="mailto:llucax+eventxx@gmail.com">drop me an
+ * e-mail</a> 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.
+ *
+ *
+ * @author Leandro Lucarella <llucax+eventxx@gmail.com>
+ *
+ * @version 0.3

  *
  *

- * @author Leandro Lucarella <llucarella@integratech.com.ar>
- * @version 0.1

  * @par License
  * @par License

- *     This program is under the BOLA license (see
- *     http://auriga.wearlab.de/~alb/bola/)
+ * This program is under the BOLA license (see
+ * http://auriga.wearlab.de/~alb/bola/ for more details or read the
+ * <a href="http://www.llucax.com.ar/~luca/repos/eventxx/LICENSE">LICENSE</a>
+ * file itself, it's very short and it basically says it's Public Domain).

  *
  */
 
  *
  */
 

+/** @example c-way.cpp
+ *
+ * This is a simple example illustrating the usage with C-like callback
+ * functions.
+ */
+
+/** @example functor-way.cpp
+ *
+ * This is a simple example illustrating the usage with function object
+ * 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
+ * and function object callbacks.
+ */
+
+/** @example bench.cpp
+ *
+ * This is a benchmark example, extracted from libevent and ported to eventxx.
+ */
+
+/** @example prio-test.cpp
+ *
+ * This is a priority usage example.
+ */
+
+/** @example test-time.cpp
+ *
+ * This is a timer usage example ported from libevent.
+ */
+
+/** @example test-eof.cpp
+ *
+ * This is some kind of test of EOF ported from libevent.
+ */
+
+/** @example test-weof.cpp
+ *
+ * Another test of EOF ported from libevent.
+ */
+
+/** @example trivial.cpp
+ *
+ * This is the most trivial example.
+ */

 
 /**
  * Namespace for all symbols libevent C++ wrapper defines.
 
 /**
  * Namespace for all symbols libevent C++ wrapper defines.


@@ -60,7 +236,14 @@ namespace internal
 }
 
 
 }
 
 

-/// @defgroup exceptions Exceptions
+/** @defgroup exceptions Exceptions
+ *
+ * eventxx makes a heavy use of exceptions. Each function has it's exceptions
+ * specified, so it's very easy to find out what exceptions to expect.
+ *
+ * Exceptions are mostly thrown when there is a programming error. So if you get
+ * an exception check your code.
+ */

 //@{
 
 
 //@{
 
 


@@ -101,7 +284,7 @@ struct invalid_event: public std::invalid_argument, public exception
  * Invalid priority exception.
  *
  * This exception is thrown when passing an invalid priority to a function. This
  * Invalid priority exception.
  *
  * This exception is thrown when passing an invalid priority to a function. This

- * usually means you don't have enought priority queues in your dispatcher, so
+ * usually means you don't have enough priority queues in your dispatcher, so

  * you should have allocated more in the constructor.
  *
  * If you hit this exception, you probably got a programming error.
  * you should have allocated more in the constructor.
  *
  * If you hit this exception, you probably got a programming error.


@@ -127,17 +310,15 @@ struct invalid_priority: public std::invalid_argument, public exception
 //@}
 
 
 //@}
 
 

-/// Miscelaneous constants
+/// Miscellaneous constants

 enum
 {
 enum
 {

-       DEFAULT_PRIORITY = -1 ///< Default priority (the middle value)
+       DEFAULT_PRIORITY = -1,      ///< Default priority (the middle value).
+       ONCE = EVLOOP_ONCE,         ///< Loop just once.
+       NONBLOCK = EVLOOP_NONBLOCK  ///< Don't block the event loop.

 };
 
 
 };
 
 

-/// C function used as callback in the C API.
-typedef void (*ccallback_type)(int, short, void*);
-
-

 /**
  * Time used for timeout values.
  *
 /**
  * Time used for timeout values.
  *


@@ -186,9 +367,60 @@ struct time: ::timeval
 }; // struct time
 
 
 }; // struct time
 
 

-/// @defgroup events Events
+/** @defgroup events Events
+ *
+ * There are many ways to specify how to handle an event. You can use use the
+ * same plain functions callbacks (see eventxx::cevent, eventxx::ctimer and
+ * eventxx::csignal) like in C or the other kind of more advanced, stateful
+ * 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.
+ *
+ * Please see each class documentation for details and examples.
+ */

 //@{
 
 //@{
 

+
+/// C function used as callback in the C API.
+typedef void (*ccallback_type)(int, short, void*);
+
+
+/**
+ * Type of events.
+ *
+ * There are 4 kind of events: eventxx::TIMEOUT, eventxx::READ, eventxx::WRITE
+ * or eventxx::SIGNAL. eventxx::PERSIST is not an event, is an event modifier
+ * flag, that tells eventxx that this event should live until dispatcher::del()
+ * is called. You can use, for example:
+ * @code
+ * eventxx::event(fd, eventxx::READ | eventxx::PERSIST, ...);
+ * @endcode
+ */
+enum type
+{
+       TIMEOUT = EV_TIMEOUT, ///< Timeout event.
+       READ = EV_READ,       ///< Read event.
+       WRITE = EV_WRITE,     ///< Write event.
+       SIGNAL = EV_SIGNAL,   ///< Signal event.
+       PERSIST = EV_PERSIST  ///< Not really an event, is an event modifier.
+};
+
+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.
  *
 /**
  * Basic event from which all events derive.
  *


@@ -208,7 +440,7 @@ struct basic_event: internal::event
         *
         * @return true if there is a pending event, false if not.
         */
         *
         * @return true if there is a pending event, false if not.
         */

-       bool pending(short ev) const throw()
+       bool pending(type ev) const throw()

        {
                // HACK libevent don't use const
                return event_pending(const_cast< basic_event* >(this), ev, 0);
        {
                // HACK libevent don't use const
                return event_pending(const_cast< basic_event* >(this), ev, 0);


@@ -232,6 +464,8 @@ struct basic_event: internal::event
         *
         * @param priority New event priority.
         *
         *
         * @param priority New event priority.
         *

+        * @pre The event must be added to some dispatcher.
+        *

         * @see dispatcher::dispatcher(int)
         */
        void priority(int priority) const throw(invalid_event, invalid_priority)
         * @see dispatcher::dispatcher(int)
         */
        void priority(int priority) const throw(invalid_event, invalid_priority)


@@ -267,13 +501,14 @@ struct basic_event: internal::event
 /**
  * Generic event object.
  *
 /**
  * Generic event object.
  *

- * This object stores all the information about an event, incluiding a callback
- * functor, which is called then the event is fired. Then template parameter
- * must be a callable object (functor) that can take 2 parameters: an integer
- * (the file descriptor of the fired event) and a short (the type of event
- * fired: EV_TIMEOUT, EV_SIGNAL, EV_READ, EV_WRITE). There is an 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.
+ * This object stores all the information about an event, including a callback
+ * functor, which is called when the event is fired. The template parameter
+ * must be a functor (callable object or function) that can take 2 parameters:
+ * 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 eventxx::ccallback_type signature, just like
+ * C @libevent API does.

  *
  * @see eventxx::event< ccallback_type >
  */
  *
  * @see eventxx::event< ccallback_type >
  */


@@ -285,17 +520,13 @@ struct event: basic_event
         * Creates a new event.
         *
         * @param fd File descriptor to monitor for events.
         * Creates a new event.
         *
         * @param fd File descriptor to monitor for events.

-        * @param ev Type of events to monitor.
+        * @param ev Type of events to monitor (see eventxx::type).

         * @param handler Callback functor.
         * @param handler Callback functor.

-        * @param priority Priority of the event.

         */
         */

-       event(int fd, short ev, F& handler, int priority = DEFAULT_PRIORITY)
-               throw(invalid_priority)
+       event(int fd, type ev, F& handler) throw()

        {
        {

-               event_set(this, fd, ev, &wrapper, reinterpret_cast< void* >(&handler));
-               if (priority != DEFAULT_PRIORITY
-                               && event_priority_set(this, priority))
-                       throw invalid_priority();
+               event_set(this, fd, static_cast< short >(ev), &wrapper,
+                               reinterpret_cast< void* >(&handler));

        }
 
        protected:
        }
 
        protected:


@@ -303,7 +534,9 @@ struct event: basic_event
                static void wrapper(int fd, short ev, void* h)
                {
                        F& handler = *reinterpret_cast< F* >(h);
                static void wrapper(int fd, short ev, void* h)
                {
                        F& handler = *reinterpret_cast< F* >(h);

-                       handler(fd, ev);
+                       // Hackish, but this way the handler can get a clean
+                       // event type
+                       handler(fd, *reinterpret_cast< type* >(&ev));

                }
 
 }; // struct event< F >
                }
 
 }; // struct event< F >


@@ -322,19 +555,13 @@ struct event< ccallback_type >: basic_event
         * Creates a new event.
         *
         * @param fd File descriptor to monitor for events.
         * Creates a new event.
         *
         * @param fd File descriptor to monitor for events.

-        * @param ev Type of events to monitor.
+        * @param ev Type of events to monitor (see eventxx::type).

         * @param handler C-style callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.
         * @param handler C-style callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.

-        * @param priority Priority of the event.

         */
         */

-       event(int fd, short ev, ccallback_type handler, void* arg,
-                       int priority = DEFAULT_PRIORITY)
-               throw(invalid_priority)
+       event(int fd, type ev, ccallback_type handler, void* arg = 0) throw()

        {
        {

-               event_set(this, fd, ev, handler, arg);
-               if (priority != DEFAULT_PRIORITY
-                               && event_priority_set(this, priority))
-                       throw invalid_priority();
+               event_set(this, fd, static_cast< short >(ev), handler, arg);

        }
 
        protected:
        }
 
        protected:


@@ -347,9 +574,12 @@ struct event< ccallback_type >: basic_event
  * Timer event object.
  *
  * This is just a special case of event that is fired only when a timeout is
  * Timer event object.
  *
  * This is just a special case of event that is fired only when a timeout is

- * reached. It's just a shortcut to event(-1, 0, handler, priority).
+ * reached. It's just a shortcut to:
+ * @code
+ * event(-1, 0, handler);
+ * @endcode

  *
  *

- * @note This event can't EV_PERSIST.
+ * @note This event can't eventxx::PERSIST.

  * @see timer< ccallback_type >
  */
 template < typename F >
  * @see timer< ccallback_type >
  */
 template < typename F >


@@ -360,16 +590,11 @@ struct timer: event< F >
         * Creates a new timer event.
         *
         * @param handler Callback functor.
         * Creates a new timer event.
         *
         * @param handler Callback functor.

-        * @param priority Priority of the event.

         */
         */

-       timer(F& handler, int priority = DEFAULT_PRIORITY)
-               throw(invalid_priority)
+       timer(F& handler) throw()

        {
                evtimer_set(this, &event< F >::wrapper,
                        reinterpret_cast< void* >(&handler));
        {
                evtimer_set(this, &event< F >::wrapper,
                        reinterpret_cast< void* >(&handler));

-               if (priority != DEFAULT_PRIORITY
-                               && event_priority_set(this, priority))
-                       throw invalid_priority();

        }
 
 }; // struct timer< F >
        }
 
 }; // struct timer< F >


@@ -378,7 +603,7 @@ struct timer: event< F >
 /**
  * This is the specialization of eventxx::timer for C-style callbacks.
  *
 /**
  * This is the specialization of eventxx::timer for C-style callbacks.
  *

- * @note This event can't EV_PERSIST.
+ * @note This event can't eventxx::PERSIST.

  * @see timer
  */
 template <>
  * @see timer
  */
 template <>


@@ -387,18 +612,13 @@ struct timer< ccallback_type >: event< ccallback_type >
 
        /**
         * Creates a new timer event.
 
        /**
         * Creates a new timer event.

-        * 
+        *

         * @param handler C-style callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.
         * @param handler C-style callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.

-        * @param priority Priority of the event.

         */
         */

-       timer(ccallback_type handler, void* arg, int priority = DEFAULT_PRIORITY)
-               throw(invalid_priority)
+       timer(ccallback_type handler, void* arg = 0) throw()

        {
                evtimer_set(this, handler, arg);
        {
                evtimer_set(this, handler, arg);

-               if (priority != DEFAULT_PRIORITY
-                               && event_priority_set(this, priority))
-                       throw invalid_priority();

        }
 
 }; // struct timer< ccallback_type >
        }
 
 }; // struct timer< ccallback_type >


@@ -408,10 +628,12 @@ struct timer< ccallback_type >: event< ccallback_type >
  * Signal event object.
  *
  * This is just a special case of event that is fired when a signal is raised
  * Signal event object.
  *
  * This is just a special case of event that is fired when a signal is raised

- * (instead of a file descriptor being active). It's just a shortcut to
- * event(signal, EV_SIGNAL, handler, priority).
+ * (instead of a file descriptor being active). It's just a shortcut to:
+ * @code
+ * event(signum, eventxx::SIGNAL, handler);
+ * @endcode

  *
  *

- * @note This event allways EV_PERSIST.
+ * @note This event always eventxx::PERSIST.

  * @see signal< ccallback_type >
  */
 template < typename F >
  * @see signal< ccallback_type >
  */
 template < typename F >


@@ -419,20 +641,15 @@ struct signal: event< F >
 {
 
        /**
 {
 
        /**

-        * Creates a new singal event.
+        * Creates a new signal event.

         *
         * @param signum Signal number to monitor.
         * @param handler Callback functor.
         *
         * @param signum Signal number to monitor.
         * @param handler Callback functor.

-        * @param priority Priority of the event.

         */
         */

-       signal(int signum, F& handler, int priority = DEFAULT_PRIORITY)
-               throw(invalid_priority)
+       signal(int signum, F& handler) throw()

        {
                signal_set(this, signum, &event< F >::wrapper,
                        reinterpret_cast< void* >(&handler));
        {
                signal_set(this, signum, &event< F >::wrapper,
                        reinterpret_cast< void* >(&handler));

-               if (priority != DEFAULT_PRIORITY
-                               && event_priority_set(this, priority))
-                       throw invalid_priority();

        }
 
        /**
        }
 
        /**


@@ -451,7 +668,7 @@ struct signal: event< F >
 /**
  * This is the specialization of eventxx::signal for C-style callbacks.
  *
 /**
  * This is the specialization of eventxx::signal for C-style callbacks.
  *

- * @note This event allways EV_PERSIST.
+ * @note This event always eventxx::PERSIST.

  * @see signal
  */
 template <>
  * @see signal
  */
 template <>


@@ -464,21 +681,15 @@ struct signal< ccallback_type >: event< ccallback_type >
         * @param signum Signal number to monitor.
         * @param handler C-style callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.
         * @param signum Signal number to monitor.
         * @param handler C-style callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.

-        * @param priority Priority of the event.

         */
         */

-       signal(int signum, ccallback_type handler, void* arg,
-                       int priority = DEFAULT_PRIORITY)
-               throw(invalid_priority)
+       signal(int signum, ccallback_type handler, void* arg = 0) throw()

        {
                signal_set(this, signum, handler, arg);
        {
                signal_set(this, signum, handler, arg);

-               if (priority != DEFAULT_PRIORITY
-                               && event_priority_set(this, priority))
-                       throw invalid_priority();

        }
 
        /**
         * Event's signal number.
        }
 
        /**
         * Event's signal number.

-        * 
+        *

         * @return Event's signal number.
         */
        int signum() const
         * @return Event's signal number.
         */
        int signum() const


@@ -498,6 +709,41 @@ typedef eventxx::timer< ccallback_type > ctimer;
 /// Shortcut to C-style signal handler.
 typedef eventxx::signal< ccallback_type > csignal;
 
 /// 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

 
 //@}
 
 
 //@}
 


@@ -505,103 +751,134 @@ typedef eventxx::signal< ccallback_type > csignal;
 /**
  * Event dispatcher.
  *
 /**
  * Event dispatcher.
  *

- * This class is the responsable for looping and dispatching events.
+ * This class is the responsible for looping and dispatching events. Every time
+ * you need an event loop you should create an instance of this class.
+ *
+ * You can @link dispatcher::add add @endlink events to the dispatcher, and you
+ * can @link dispatcher::del remove @endlink them later or you can @link
+ * dispatcher::add_once add events to be processed just once @endlink. You can
+ * @link dispatcher::dispatch loop once or forever @endlink (well, of course you
+ * can break that forever removing all the events or by @link dispatcher::exit
+ * exiting the loop @endlink).

  */
 struct dispatcher
 {
 
        /**
  */
 struct dispatcher
 {
 
        /**

-        * Creates a default dispatcher (with just 1 prioriority).
+        * Creates a default dispatcher (with just 1 priority).

         *
         * @see dispatcher(int) if you want to create a dispatcher with more
         *
         * @see dispatcher(int) if you want to create a dispatcher with more

-        *      prioriorities.
+        *      priorities.

         */
        dispatcher() throw()
        {
         */
        dispatcher() throw()
        {

-               _event_base = static_cast< internal::event_base* >(internal::event_init());
+               _event_base = static_cast< internal::event_base* >(
+                               internal::event_init());

        }
 
        /**
        }
 
        /**

-        * Creates a dispatcher with npriorities prioriorities.
-        * 
+        * Creates a dispatcher with npriorities priorities.
+        *

         * @param npriorities Number of priority queues to use.
         */
        dispatcher(int npriorities) throw(std::bad_alloc)
        {
         * @param npriorities Number of priority queues to use.
         */
        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
                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); }
        ~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
 
        /**
         * Adds an event to the dispatcher.
         *
         * @param e Event to add.
 #endif
 
        /**
         * Adds an event to the dispatcher.
         *
         * @param e Event to add.

+        * @param priority Priority of the event.

         */
         */

-       void add(basic_event& e) throw()
+       void add(basic_event& e, int priority = DEFAULT_PRIORITY)
+               throw(invalid_priority)

        {
                internal::event_base_set(_event_base, &e);
        {
                internal::event_base_set(_event_base, &e);

+               if (priority != DEFAULT_PRIORITY
+                               && internal::event_priority_set(&e, priority))
+                       throw invalid_priority();

                internal::event_add(&e, 0);
        }
 
        /**
         * Adds an event to the dispatcher with a timeout.
         *
                internal::event_add(&e, 0);
        }
 
        /**
         * Adds an event to the dispatcher with a timeout.
         *

-        * The event is fired when there is activity on e or when to is elapsed,
+        * The event is fired when there is activity on e or when to has elapsed,

         * whatever come first.
         *
         * @param e Event to add.
         * @param to Timeout.
         * whatever come first.
         *
         * @param e Event to add.
         * @param to Timeout.

+        * @param priority Priority of the event.

         */
         */

-       void add(basic_event& e, const time& to) throw()
+       void add(basic_event& e, const time& to,
+                       int priority = DEFAULT_PRIORITY)
+               throw(invalid_priority)

        {
                internal::event_base_set(_event_base, &e);
        {
                internal::event_base_set(_event_base, &e);

-               internal::event_add(&e, const_cast< time* >(&to)); // XXX HACK libevent don't use const
+               if (priority != DEFAULT_PRIORITY
+                               && internal::event_priority_set(&e, priority))
+                       throw invalid_priority();
+               // XXX HACK libevent don't use const
+               internal::event_add(&e, const_cast< time* >(&to));

        }
 
        /**
         * Adds a temporary event.
         *
         * Adds a temporary event, without the need of instantiating a new event
        }
 
        /**
         * Adds a temporary event.
         *
         * Adds a temporary event, without the need of instantiating a new event

-        * object. Events added this way can't EV_PERSIST.
+        * object. Events added this way can't eventxx::PERSIST.

         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.
         * @param handler Callback function.
         */
        template < typename F >
         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.
         * @param handler Callback function.
         */
        template < typename F >

-       void add_once(int fd, short ev, F& handler)
+       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);

        }
 
        /**
         * Adds a temporary event to with a C-style callback.
         *
         * Adds a temporary event, without the need of instantiating a new event
        }
 
        /**
         * Adds a temporary event to with a C-style callback.
         *
         * Adds a temporary event, without the need of instantiating a new event

-        * object. Events added this way can't EV_PERSIST.
+        * object. Events added this way can't eventxx::PERSIST.

         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.
         * @param handler Callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.
         */
         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.
         * @param handler Callback function.
         * @param arg Arbitrary pointer to pass to the handler as argument.
         */

-       void add_once(int fd, short ev, ccallback_type handler, void* arg)
+       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);

        }
 
        /**
         * Adds a temporary event.
         *
         * Adds a temporary event, without the need of instantiating a new event
        }
 
        /**
         * Adds a temporary event.
         *
         * Adds a temporary event, without the need of instantiating a new event

-        * object. Events added this way can't EV_PERSIST.
+        * object. Events added this way can't eventxx::PERSIST.

         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.
         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.


@@ -609,18 +886,20 @@ struct dispatcher
         * @param to Timeout.
         */
        template < typename F >
         * @param to Timeout.
         */
        template < typename F >

-       void add_once(int fd, short ev, F& handler, const time& to)
+       void add_once(int fd, type ev, F& handler, const time& to)

        {
        {

-               internal::event_once(fd, ev, &dispatcher::wrapper< F >,
-                               reinterpret_cast< void* >(&handler),
-                               const_cast< time* >(&to)); // XXX HACK libevent don't use const
+               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));

        }
 
        /**
         * Adds a temporary event with a C-style callback.
         *
         * Adds a temporary event, without the need of instantiating a new event
        }
 
        /**
         * Adds a temporary event with a C-style callback.
         *
         * Adds a temporary event, without the need of instantiating a new event

-        * object. Events added this way can't EV_PERSIST.
+        * object. Events added this way can't eventxx::PERSIST.

         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.
         *
         * @param fd File descriptor to monitor for events.
         * @param ev Type of events to monitor.


@@ -628,9 +907,12 @@ struct dispatcher
         * @param arg Arbitrary pointer to pass to the handler as argument.
         * @param to Timeout.
         */
         * @param arg Arbitrary pointer to pass to the handler as argument.
         * @param to Timeout.
         */

-       void add_once(int fd, short 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, static_cast< short >(ev), handler, arg,
+                               // XXX HACK libevent don't use const
+                               const_cast< time* >(&to));

        }
 
        /**
        }
 
        /**


@@ -647,7 +929,8 @@ struct dispatcher
        {
                internal::event_once(-1, EV_TIMEOUT, &dispatcher::wrapper< F >,
                                reinterpret_cast< void* >(&handler),
        {
                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));

        }
 
        /**
        }
 
        /**


@@ -662,7 +945,9 @@ struct dispatcher
         */
        void add_once_timer(ccallback_type handler, void* arg, const time& to)
        {
         */
        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));

        }
 
        /**
        }
 
        /**


@@ -680,20 +965,25 @@ struct dispatcher
        /**
         * Main dispatcher loop.
         *
        /**
         * Main dispatcher loop.
         *

-        * This function takes the control of the program, waiting for event and
-        * calling it's callbacks when they are fired. It only returns under
+        * This function takes the control of the program, waiting for an event
+        * and calling its callbacks when it's fired. It only returns under

         * this conditions:
         * - exit() was called.
         * - All events were del()eted.
         * - Another internal error.
         * this conditions:
         * - exit() was called.
         * - All events were del()eted.
         * - Another internal error.

-        * - LOOP_ONCE flag was set.
-        * - LOOP_NONBLOCK flag was set.
+        * - eventxx::ONCE flag was set.
+        * - eventxx::NONBLOCK flag was set.
+        *
+        * @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.

         *
         *

-        * @param flags If EVLOOP_ONCE is specified, then just one event is
-        *              processed, if EVLOOP_NONBLOCK is specified, then this
-        *              function returns whenever as an event or not.
+        * @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);
        }
        {
                return internal::event_base_loop(_event_base, flags);
        }


@@ -701,11 +991,17 @@ struct dispatcher
        /**
         * Exit the dispatch() loop.
         *
        /**
         * Exit the dispatch() loop.
         *

-        * @param to If a timeout is given, the loop exits after to is passed.
+        * @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)

        {
        {

-               return internal::event_base_loopexit(_event_base, const_cast< time* >(&to)); // XXX HACK libevent don't use const
+               // XXX HACK libevent don't use const
+               return internal::event_base_loopexit(_event_base,
+                       const_cast< time* >(&to));

        }
 
        protected:
        }
 
        protected:


@@ -714,13 +1010,12 @@ struct dispatcher
                static void wrapper(int fd, short ev, void* h)
                {
                        F& handler = *reinterpret_cast< F* >(h);
                static void wrapper(int fd, short ev, void* h)
                {
                        F& handler = *reinterpret_cast< F* >(h);

-                       handler(fd, ev);
+                       handler(fd, *reinterpret_cast< type* >(&ev));

                }
 
 }; // struct dispatcher
 
                }
 
 }; // struct dispatcher
 

-
-} // namespace event
+} // namespace eventxx

 
 #endif // _EVENTXX_HPP_
 
 
 #endif // _EVENTXX_HPP_