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/*
* Copyright (c) 2008 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* High-level wrapper around the "poll" system call.
*
* Intended usage is for the program's main loop to go about its business
* servicing whatever events it needs to. Then, when it runs out of immediate
* tasks, it calls each subordinate module's "wait" function, which in turn
* calls one (or more) of the functions poll_fd_wait(), poll_immediate_wake(),
* and poll_timer_wait() to register to be awakened when the appropriate event
* occurs. Then the main loop calls poll_block(), which blocks until one of
* the registered events happens.
*
* There is also some support for autonomous subroutines that are executed by
* poll_block() when a file descriptor becomes ready. To prevent these
* routines from starving if events are continuously ready, the application
* should bound the amount of work it does between poll_block() calls. */
#ifndef POLL_LOOP_H
#define POLL_LOOP_H 1
#include <poll.h>
struct poll_waiter;
/* Schedule events to wake up the following poll_block(). */
struct poll_waiter *poll_fd_wait(int fd, short int events);
void poll_timer_wait(int msec);
void poll_immediate_wake(void);
/* Wait until an event occurs. */
void poll_block(void);
/* Autonomous function callbacks. */
typedef void poll_fd_func(int fd, short int revents, void *aux);
struct poll_waiter *poll_fd_callback(int fd, short int events,
poll_fd_func *, void *aux);
/* Cancel a file descriptor callback or event. */
void poll_cancel(struct poll_waiter *);
#endif /* poll-loop.h */
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