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author | Jonathan McCrohan <jmccrohan@gmail.com> | 2012-04-14 12:56:48 +0100 |
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committer | Jonathan McCrohan <jmccrohan@gmail.com> | 2012-04-14 12:56:48 +0100 |
commit | 0b624384cd52be20e61284551d832b499d7b7707 (patch) | |
tree | 6f95a4bbef47abc9720b96c0722e8f632aef228a /linux/avahi-common/watch.h | |
download | libphidget21-0b624384cd52be20e61284551d832b499d7b7707.tar.gz |
Imported Upstream version 2.1.8.20120216upstream/2.1.8.20120216
Diffstat (limited to '')
-rw-r--r-- | linux/avahi-common/watch.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/linux/avahi-common/watch.h b/linux/avahi-common/watch.h new file mode 100644 index 0000000..c9b71a8 --- /dev/null +++ b/linux/avahi-common/watch.h @@ -0,0 +1,99 @@ +#ifndef foowatchhfoo +#define foowatchhfoo + +/* $Id: watch.h 1335 2006-11-19 08:04:07Z lathiat $ */ + +/*** + 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 <sys/poll.h> +#include <sys/time.h> + +#include <avahi-common/cdecl.h> + +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, /**< 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 losely 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; + + /** 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); + + /** 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 + +#endif + |