1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #pragma once
30 
31 /**
32  * @file sys/epoll.h
33  * @brief I/O event file descriptors.
34  */
35 
36 #include <sys/cdefs.h>
37 #include <sys/types.h>
38 #include <signal.h> /* For sigset_t. */
39 
40 #include <linux/eventpoll.h>
41 
42 __BEGIN_DECLS
43 
44 /**
45  * [epoll_create(2)](http://man7.org/linux/man-pages/man2/epoll_create.2.html)
46  * creates a new [epoll](http://man7.org/linux/man-pages/man7/epoll.7.html)
47  * file descriptor.
48  *
49  * Returns a new file descriptor on success and returns -1 and sets `errno` on
50  * failure.
51  */
52 int epoll_create(int __size);
53 
54 /**
55  * [epoll_create1(2)](http://man7.org/linux/man-pages/man2/epoll_create1.2.html)
56  * creates a new [epoll](http://man7.org/linux/man-pages/man7/epoll.7.html)
57  * file descriptor with the given flags.
58  *
59  * Returns a new file descriptor on success and returns -1 and sets `errno` on
60  * failure.
61  */
62 int epoll_create1(int __flags);
63 
64 /**
65  * [epoll_ctl(2)](http://man7.org/linux/man-pages/man2/epoll_ctl.2.html)
66  * adds/modifies/removes file descriptors from the given epoll file descriptor.
67  *
68  * Returns 0 on success and returns -1 and sets `errno` on failure.
69  */
70 int epoll_ctl(int __epoll_fd, int __op, int __fd, struct epoll_event* __BIONIC_COMPLICATED_NULLNESS __event);
71 
72 /**
73  * [epoll_wait(2)](http://man7.org/linux/man-pages/man2/epoll_wait.2.html)
74  * waits for an event on the given epoll file descriptor.
75  *
76  * Returns the number of ready file descriptors on success, 0 on timeout,
77  * or -1 and sets `errno` on failure.
78  */
79 int epoll_wait(int __epoll_fd, struct epoll_event* _Nonnull __events, int __event_count, int __timeout_ms);
80 
81 /**
82  * Like epoll_wait() but atomically applying the given signal mask.
83  */
84 int epoll_pwait(int __epoll_fd, struct epoll_event* _Nonnull __events, int __event_count, int __timeout_ms, const sigset_t* _Nullable __mask);
85 
86 /**
87  * Like epoll_pwait() but using a 64-bit signal mask even on 32-bit systems.
88  *
89  * Available since API level 28.
90  */
91 int epoll_pwait64(int __epoll_fd, struct epoll_event* _Nonnull __events, int __event_count, int __timeout_ms, const sigset64_t* _Nullable __mask) __INTRODUCED_IN(28);
92 
93 /**
94  * Like epoll_pwait() but with a `struct timespec` timeout, for nanosecond resolution.
95  *
96  * Available since API level 35.
97  */
98 int epoll_pwait2(int __epoll_fd, struct epoll_event* _Nonnull __events, int __event_count, const struct timespec* _Nullable __timeout, const sigset_t* _Nullable __mask) __INTRODUCED_IN(35);
99 
100 /**
101  * Like epoll_pwait2() but using a 64-bit signal mask even on 32-bit systems.
102  *
103  * Available since API level 35.
104  */
105 int epoll_pwait2_64(int __epoll_fd, struct epoll_event* _Nonnull __events, int __event_count, const struct timespec* _Nullable __timeout, const sigset64_t* _Nullable __mask) __INTRODUCED_IN(35);
106 
107 __END_DECLS
108