USA.
***/
+/** \file watch.h Simplistic main loop abstraction */
+
#include <sys/poll.h>
-#include <avahi-common/cdecl.h>
+#include <sys/time.h>
-#include "timeval.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,
- 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);
-typedef void (*AvahiWakeupCallback)(AvahiPoll *api, 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 {
- void* userdata;
-
- AvahiWatch* (*watch_new)(AvahiPoll *api, int fd, AvahiWatchEvent event, AvahiWatchCallback callback, void *userdata);
+
+ /** 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);
- void (*set_wakeup)(AvahiPoll *api, const struct timeval *tv, AvahiWakeupCallback callback, void *userdata);
+ /** Free a timeout. It is safe to call this function from an AvahiTimeoutCallback */
+ void (*timeout_free)(AvahiTimeout *t);
};
AVAHI_C_DECL_END