1/* Copyright (C) 1996-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18/*
19 * ISO/IEC 9945-1:1996 6.7: Asynchronous Input and Output
20 */
21
22#ifndef _AIO_H
23#define _AIO_H 1
24
25#include <features.h>
26#include <sys/types.h>
27#include <bits/types/sigevent_t.h>
28#include <bits/sigevent-consts.h>
29#include <bits/types/struct_timespec.h>
30
31__BEGIN_DECLS
32
33/* Asynchronous I/O control block. */
34struct aiocb
35{
36 int aio_fildes; /* File desriptor. */
37 int aio_lio_opcode; /* Operation to be performed. */
38 int aio_reqprio; /* Request priority offset. */
39 volatile void *aio_buf; /* Location of buffer. */
40 size_t aio_nbytes; /* Length of transfer. */
41 struct sigevent aio_sigevent; /* Signal number and value. */
42
43 /* Internal members. */
44 struct aiocb *__next_prio;
45 int __abs_prio;
46 int __policy;
47 int __error_code;
48 __ssize_t __return_value;
49
50#ifndef __USE_FILE_OFFSET64
51 __off_t aio_offset; /* File offset. */
52 char __pad[sizeof (__off64_t) - sizeof (__off_t)];
53#else
54 __off64_t aio_offset; /* File offset. */
55#endif
56 char __glibc_reserved[32];
57};
58
59/* The same for the 64bit offsets. Please note that the members aio_fildes
60 to __return_value have to be the same in aiocb and aiocb64. */
61#ifdef __USE_LARGEFILE64
62struct aiocb64
63{
64 int aio_fildes; /* File desriptor. */
65 int aio_lio_opcode; /* Operation to be performed. */
66 int aio_reqprio; /* Request priority offset. */
67 volatile void *aio_buf; /* Location of buffer. */
68 size_t aio_nbytes; /* Length of transfer. */
69 struct sigevent aio_sigevent; /* Signal number and value. */
70
71 /* Internal members. */
72 struct aiocb *__next_prio;
73 int __abs_prio;
74 int __policy;
75 int __error_code;
76 __ssize_t __return_value;
77
78 __off64_t aio_offset; /* File offset. */
79 char __glibc_reserved[32];
80};
81#endif
82
83
84#ifdef __USE_GNU
85/* To customize the implementation one can use the following struct.
86 This implementation follows the one in Irix. */
87struct aioinit
88 {
89 int aio_threads; /* Maximal number of threads. */
90 int aio_num; /* Number of expected simultanious requests. */
91 int aio_locks; /* Not used. */
92 int aio_usedba; /* Not used. */
93 int aio_debug; /* Not used. */
94 int aio_numusers; /* Not used. */
95 int aio_idle_time; /* Number of seconds before idle thread
96 terminates. */
97 int aio_reserved;
98 };
99#endif
100
101
102/* Return values of cancelation function. */
103enum
104{
105 AIO_CANCELED,
106#define AIO_CANCELED AIO_CANCELED
107 AIO_NOTCANCELED,
108#define AIO_NOTCANCELED AIO_NOTCANCELED
109 AIO_ALLDONE
110#define AIO_ALLDONE AIO_ALLDONE
111};
112
113
114/* Operation codes for `aio_lio_opcode'. */
115enum
116{
117 LIO_READ,
118#define LIO_READ LIO_READ
119 LIO_WRITE,
120#define LIO_WRITE LIO_WRITE
121 LIO_NOP
122#define LIO_NOP LIO_NOP
123};
124
125
126/* Synchronization options for `lio_listio' function. */
127enum
128{
129 LIO_WAIT,
130#define LIO_WAIT LIO_WAIT
131 LIO_NOWAIT
132#define LIO_NOWAIT LIO_NOWAIT
133};
134
135
136/* Allow user to specify optimization. */
137#ifdef __USE_GNU
138extern void aio_init (const struct aioinit *__init) __THROW __nonnull ((1));
139#endif
140
141
142#ifndef __USE_FILE_OFFSET64
143/* Enqueue read request for given number of bytes and the given priority. */
144extern int aio_read (struct aiocb *__aiocbp) __THROW __nonnull ((1));
145/* Enqueue write request for given number of bytes and the given priority. */
146extern int aio_write (struct aiocb *__aiocbp) __THROW __nonnull ((1));
147
148/* Initiate list of I/O requests. */
149extern int lio_listio (int __mode,
150 struct aiocb *const __list[__restrict_arr],
151 int __nent, struct sigevent *__restrict __sig)
152 __THROW __nonnull ((2));
153
154/* Retrieve error status associated with AIOCBP. */
155extern int aio_error (const struct aiocb *__aiocbp) __THROW __nonnull ((1));
156/* Return status associated with AIOCBP. */
157extern __ssize_t aio_return (struct aiocb *__aiocbp) __THROW __nonnull ((1));
158
159/* Try to cancel asynchronous I/O requests outstanding against file
160 descriptor FILDES. */
161extern int aio_cancel (int __fildes, struct aiocb *__aiocbp) __THROW;
162
163/* Suspend calling thread until at least one of the asynchronous I/O
164 operations referenced by LIST has completed.
165
166 This function is a cancellation point and therefore not marked with
167 __THROW. */
168extern int aio_suspend (const struct aiocb *const __list[], int __nent,
169 const struct timespec *__restrict __timeout)
170 __nonnull ((1));
171
172/* Force all operations associated with file desriptor described by
173 `aio_fildes' member of AIOCBP. */
174extern int aio_fsync (int __operation, struct aiocb *__aiocbp)
175 __THROW __nonnull ((2));
176#else
177# ifdef __REDIRECT_NTH
178extern int __REDIRECT_NTH (aio_read, (struct aiocb *__aiocbp), aio_read64)
179 __nonnull ((1));
180extern int __REDIRECT_NTH (aio_write, (struct aiocb *__aiocbp), aio_write64)
181 __nonnull ((1));
182
183extern int __REDIRECT_NTH (lio_listio,
184 (int __mode,
185 struct aiocb *const __list[__restrict_arr],
186 int __nent, struct sigevent *__restrict __sig),
187 lio_listio64) __nonnull ((2));
188
189extern int __REDIRECT_NTH (aio_error, (const struct aiocb *__aiocbp),
190 aio_error64) __nonnull ((1));
191extern __ssize_t __REDIRECT_NTH (aio_return, (struct aiocb *__aiocbp),
192 aio_return64) __nonnull ((1));
193
194extern int __REDIRECT_NTH (aio_cancel,
195 (int __fildes, struct aiocb *__aiocbp),
196 aio_cancel64);
197
198extern int __REDIRECT_NTH (aio_suspend,
199 (const struct aiocb *const __list[], int __nent,
200 const struct timespec *__restrict __timeout),
201 aio_suspend64) __nonnull ((1));
202
203extern int __REDIRECT_NTH (aio_fsync,
204 (int __operation, struct aiocb *__aiocbp),
205 aio_fsync64) __nonnull ((2));
206
207# else
208# define aio_read aio_read64
209# define aio_write aio_write64
210# define lio_listio lio_listio64
211# define aio_error aio_error64
212# define aio_return aio_return64
213# define aio_cancel aio_cancel64
214# define aio_suspend aio_suspend64
215# define aio_fsync aio_fsync64
216# endif
217#endif
218
219#ifdef __USE_LARGEFILE64
220extern int aio_read64 (struct aiocb64 *__aiocbp) __THROW __nonnull ((1));
221extern int aio_write64 (struct aiocb64 *__aiocbp) __THROW __nonnull ((1));
222
223extern int lio_listio64 (int __mode,
224 struct aiocb64 *const __list[__restrict_arr],
225 int __nent, struct sigevent *__restrict __sig)
226 __THROW __nonnull ((2));
227
228extern int aio_error64 (const struct aiocb64 *__aiocbp)
229 __THROW __nonnull ((1));
230extern __ssize_t aio_return64 (struct aiocb64 *__aiocbp)
231 __THROW __nonnull ((1));
232
233extern int aio_cancel64 (int __fildes, struct aiocb64 *__aiocbp) __THROW;
234
235extern int aio_suspend64 (const struct aiocb64 *const __list[], int __nent,
236 const struct timespec *__restrict __timeout)
237 __THROW __nonnull ((1));
238
239extern int aio_fsync64 (int __operation, struct aiocb64 *__aiocbp)
240 __THROW __nonnull ((2));
241#endif
242
243__END_DECLS
244
245#endif /* aio.h */
246