X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=avahi-common%2Fwatch.h;h=86e63d3bf59f6afc15692dd56a293f87944e532d;hb=9c0f9c65093cfa53d45f9b68782321eb8063a032;hp=b26c2ba1aa86773b45ec06499c654a7cf5b51a55;hpb=5d047523c87ba11aad8c384f7ffde25b4dd746ed;p=catta diff --git a/avahi-common/watch.h b/avahi-common/watch.h index b26c2ba..86e63d3 100644 --- a/avahi-common/watch.h +++ b/avahi-common/watch.h @@ -1,54 +1,94 @@ #ifndef foowatchhfoo #define foowatchhfoo -/* $Id$ */ - /*** This file is part of avahi. - + avahi is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. - + avahi is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. - + You should have received a copy of the GNU Lesser General Public License along with avahi; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. ***/ +/** \file watch.h Simplistic main loop abstraction */ + #include -#include +#include -#include "timeval.h" +#include AVAHI_C_DECL_BEGIN +/** An I/O watch object */ typedef struct AvahiWatch AvahiWatch; + +/** A timeout watch object */ +typedef struct AvahiTimeout AvahiTimeout; + +/** An event polling abstraction object */ typedef struct AvahiPoll AvahiPoll; +/** Type of watch events */ typedef enum { - AVAHI_WATCH_IN = POLLIN, - AVAHI_WATCH_OUT = POLLOUT, - AVAHI_WATCH_ERR = POLLERR, - AVAHI_WATCH_HUP = POLLHUP + AVAHI_WATCH_IN = POLLIN, /**< Input event */ + AVAHI_WATCH_OUT = POLLOUT, /**< Output event */ + AVAHI_WATCH_ERR = POLLERR, /**< Error event */ + AVAHI_WATCH_HUP = POLLHUP /**< Hangup event */ } AvahiWatchEvent; +/** Called whenever an I/O event happens on an I/O watch */ typedef void (*AvahiWatchCallback)(AvahiWatch *w, int fd, AvahiWatchEvent event, void *userdata); +/** Called when the timeout is reached */ +typedef void (*AvahiTimeoutCallback)(AvahiTimeout *t, void *userdata); + +/** Defines an abstracted event polling API. This may be used to + connect Avahi to other main loops. This is loosely based on Unix + poll(2). A consumer will call watch_new() for all file descriptors it + wants to listen for events on. In addition he can call timeout_new() + to define time based events .*/ struct AvahiPoll { + + /** Some abstract user data usable by the provider of the API */ void* userdata; - - AvahiWatch* (*watch_new)(AvahiPoll *api, int fd, AvahiWatchEvent event, AvahiWatchCallback callback, void *userdata); + + /** Create a new watch for the specified file descriptor and for + * the specified events. The API will call the callback function + * whenever any of the events happens. */ + AvahiWatch* (*watch_new)(const AvahiPoll *api, int fd, AvahiWatchEvent event, AvahiWatchCallback callback, void *userdata); + + /** Update the events to wait for. It is safe to call this function from an AvahiWatchCallback */ void (*watch_update)(AvahiWatch *w, AvahiWatchEvent event); + + /** Return the events that happened. It is safe to call this function from an AvahiWatchCallback */ + AvahiWatchEvent (*watch_get_events)(AvahiWatch *w); + + /** Free a watch. It is safe to call this function from an AvahiWatchCallback */ void (*watch_free)(AvahiWatch *w); - - void (*set_wakeup_time)(AvahiPoll *api, const struct timeval *tv); + + /** Set a wakeup time for the polling loop. The API will call the + callback function when the absolute time *tv is reached. If tv is + NULL, the timeout is disabled. After the timeout expired the + callback function will be called and the timeout is disabled. You + can reenable it by calling timeout_update() */ + AvahiTimeout* (*timeout_new)(const AvahiPoll *api, const struct timeval *tv, AvahiTimeoutCallback callback, void *userdata); + + /** Update the absolute expiration time for a timeout, If tv is + * NULL, the timeout is disabled. It is safe to call this function from an AvahiTimeoutCallback */ + void (*timeout_update)(AvahiTimeout *, const struct timeval *tv); + + /** Free a timeout. It is safe to call this function from an AvahiTimeoutCallback */ + void (*timeout_free)(AvahiTimeout *t); }; AVAHI_C_DECL_END