1/* Copyright (C) 1996-2000,2003,2004,2007 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, write to the Free
16   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17   02111-1307 USA.  */
18
19/*
20 * ISO/IEC 9945-1:1996 6.7: Asynchronous Input and Output
21 */
22
23#ifndef _AIO_H
24#define _AIO_H	1
25
26#include <features.h>
27#include <fcntl.h>
28#include <signal.h>
29#include <time.h>
30#include <sys/types.h>
31
32__BEGIN_DECLS
33
34/* Asynchronous I/O control block.  */
35struct aiocb
36{
37  int aio_fildes;		/* File desriptor.  */
38  int aio_lio_opcode;		/* Operation to be performed.  */
39  int aio_reqprio;		/* Request priority offset.  */
40  volatile void *aio_buf;	/* Location of buffer.  */
41  size_t aio_nbytes;		/* Length of transfer.  */
42  struct sigevent aio_sigevent;	/* Signal number and value.  */
43
44  /* Internal members.  */
45  struct aiocb *__next_prio;
46  int __abs_prio;
47  int __policy;
48  int __error_code;
49  __ssize_t __return_value;
50
51#ifndef __USE_FILE_OFFSET64
52  __off_t aio_offset;		/* File offset.  */
53  char __pad[sizeof (__off64_t) - sizeof (__off_t)];
54#else
55  __off64_t aio_offset;		/* File offset.  */
56#endif
57  char __unused[32];
58};
59
60/* The same for the 64bit offsets.  Please note that the members aio_fildes
61   to __return_value have to be the same in aiocb and aiocb64.  */
62#ifdef __USE_LARGEFILE64
63struct aiocb64
64{
65  int aio_fildes;		/* File desriptor.  */
66  int aio_lio_opcode;		/* Operation to be performed.  */
67  int aio_reqprio;		/* Request priority offset.  */
68  volatile void *aio_buf;	/* Location of buffer.  */
69  size_t aio_nbytes;		/* Length of transfer.  */
70  struct sigevent aio_sigevent;	/* Signal number and value.  */
71
72  /* Internal members.  */
73  struct aiocb *__next_prio;
74  int __abs_prio;
75  int __policy;
76  int __error_code;
77  __ssize_t __return_value;
78
79  __off64_t aio_offset;		/* File offset.  */
80  char __unused[32];
81};
82#endif
83
84
85#ifdef __USE_GNU
86/* To customize the implementation one can use the following struct.
87   This implementation follows the one in Irix.  */
88struct aioinit
89  {
90    int aio_threads;		/* Maximal number of threads.  */
91    int aio_num;		/* Number of expected simultanious requests. */
92    int aio_locks;		/* Not used.  */
93    int aio_usedba;		/* Not used.  */
94    int aio_debug;		/* Not used.  */
95    int aio_numusers;		/* Not used.  */
96    int aio_idle_time;		/* Number of seconds before idle thread
97				   terminates.  */
98    int aio_reserved;
99  };
100#endif
101
102
103/* Return values of cancelation function.  */
104enum
105{
106  AIO_CANCELED,
107#define AIO_CANCELED AIO_CANCELED
108  AIO_NOTCANCELED,
109#define AIO_NOTCANCELED AIO_NOTCANCELED
110  AIO_ALLDONE
111#define AIO_ALLDONE AIO_ALLDONE
112};
113
114
115/* Operation codes for `aio_lio_opcode'.  */
116enum
117{
118  LIO_READ,
119#define LIO_READ LIO_READ
120  LIO_WRITE,
121#define LIO_WRITE LIO_WRITE
122  LIO_NOP
123#define LIO_NOP LIO_NOP
124};
125
126
127/* Synchronization options for `lio_listio' function.  */
128enum
129{
130  LIO_WAIT,
131#define LIO_WAIT LIO_WAIT
132  LIO_NOWAIT
133#define LIO_NOWAIT LIO_NOWAIT
134};
135
136
137/* Allow user to specify optimization.  */
138#ifdef __USE_GNU
139extern void aio_init (__const struct aioinit *__init) __THROW __nonnull ((1));
140#endif
141
142
143#ifndef __USE_FILE_OFFSET64
144/* Enqueue read request for given number of bytes and the given priority.  */
145extern int aio_read (struct aiocb *__aiocbp) __THROW __nonnull ((1));
146/* Enqueue write request for given number of bytes and the given priority.  */
147extern int aio_write (struct aiocb *__aiocbp) __THROW __nonnull ((1));
148
149/* Initiate list of I/O requests.  */
150extern int lio_listio (int __mode,
151		       struct aiocb *__const __list[__restrict_arr],
152		       int __nent, struct sigevent *__restrict __sig)
153  __THROW __nonnull ((2));
154
155/* Retrieve error status associated with AIOCBP.  */
156extern int aio_error (__const struct aiocb *__aiocbp) __THROW __nonnull ((1));
157/* Return status associated with AIOCBP.  */
158extern __ssize_t aio_return (struct aiocb *__aiocbp) __THROW __nonnull ((1));
159
160/* Try to cancel asynchronous I/O requests outstanding against file
161   descriptor FILDES.  */
162extern int aio_cancel (int __fildes, struct aiocb *__aiocbp) __THROW;
163
164/* Suspend calling thread until at least one of the asynchronous I/O
165   operations referenced by LIST has completed.
166
167   This function is a cancellation point and therefore not marked with
168   __THROW.  */
169extern int aio_suspend (__const struct aiocb *__const __list[], int __nent,
170			__const struct timespec *__restrict __timeout)
171  __nonnull ((1));
172
173/* Force all operations associated with file desriptor described by
174   `aio_fildes' member of AIOCBP.  */
175extern int aio_fsync (int __operation, struct aiocb *__aiocbp)
176  __THROW __nonnull ((2));
177#else
178# ifdef __REDIRECT_NTH
179extern int __REDIRECT_NTH (aio_read, (struct aiocb *__aiocbp), aio_read64)
180  __nonnull ((1));
181extern int __REDIRECT_NTH (aio_write, (struct aiocb *__aiocbp), aio_write64)
182  __nonnull ((1));
183
184extern int __REDIRECT_NTH (lio_listio,
185			   (int __mode,
186			    struct aiocb *__const __list[__restrict_arr],
187			    int __nent, struct sigevent *__restrict __sig),
188			   lio_listio64) __nonnull ((2));
189
190extern int __REDIRECT_NTH (aio_error, (__const struct aiocb *__aiocbp),
191			   aio_error64) __nonnull ((1));
192extern __ssize_t __REDIRECT_NTH (aio_return, (struct aiocb *__aiocbp),
193				 aio_return64) __nonnull ((1));
194
195extern int __REDIRECT_NTH (aio_cancel,
196			   (int __fildes, struct aiocb *__aiocbp),
197			   aio_cancel64);
198
199extern int __REDIRECT_NTH (aio_suspend,
200			   (__const struct aiocb *__const __list[], int __nent,
201			    __const struct timespec *__restrict __timeout),
202			   aio_suspend64) __nonnull ((1));
203
204extern int __REDIRECT_NTH (aio_fsync,
205			   (int __operation, struct aiocb *__aiocbp),
206			   aio_fsync64) __nonnull ((2));
207
208# else
209#  define aio_read aio_read64
210#  define aio_write aio_write64
211#  define lio_listio lio_listio64
212#  define aio_error aio_error64
213#  define aio_return aio_return64
214#  define aio_cancel aio_cancel64
215#  define aio_suspend aio_suspend64
216#  define aio_fsync aio_fsync64
217# endif
218#endif
219
220#ifdef __USE_LARGEFILE64
221extern int aio_read64 (struct aiocb64 *__aiocbp) __THROW __nonnull ((1));
222extern int aio_write64 (struct aiocb64 *__aiocbp) __THROW __nonnull ((1));
223
224extern int lio_listio64 (int __mode,
225			 struct aiocb64 *__const __list[__restrict_arr],
226			 int __nent, struct sigevent *__restrict __sig)
227  __THROW __nonnull ((2));
228
229extern int aio_error64 (__const struct aiocb64 *__aiocbp)
230  __THROW __nonnull ((1));
231extern __ssize_t aio_return64 (struct aiocb64 *__aiocbp)
232  __THROW __nonnull ((1));
233
234extern int aio_cancel64 (int __fildes, struct aiocb64 *__aiocbp) __THROW;
235
236extern int aio_suspend64 (__const struct aiocb64 *__const __list[], int __nent,
237			  __const struct timespec *__restrict __timeout)
238  __THROW __nonnull ((1));
239
240extern int aio_fsync64 (int __operation, struct aiocb64 *__aiocbp)
241  __THROW __nonnull ((2));
242#endif
243
244__END_DECLS
245
246#endif /* aio.h */
247