rt/aio.h

   1 /* Copyright (C) 1996, 1997, 1998 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 Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    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    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 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.  */
  35 struct 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.  */
  61 #ifdef __USE_LARGEFILE64
  62 struct 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   int __abs_prio;
  73   int __policy;
  74   int __error_code;
  75   __ssize_t __return_value;
  76
  77   __off64_t aio_offset;         /* File offset.  */
  78   char __unused[32];
  79 };
  80 #endif
  81
  82
  83 #ifdef __USE_GNU
  84 /* To customize the implementation one can use the following struct.
  85    This implementation follows the one in Irix.  */
  86 struct aioinit
  87   {
  88     int aio_threads;            /* Maximal number of threads.  */
  89     int aio_num;                /* Number of expected simultanious requests. */
  90     int aio_locks;              /* Not used.  */
  91     int aio_usedba;             /* Not used.  */
  92     int aio_debug;              /* Not used.  */
  93     int aio_numusers;           /* Not used.  */
  94     int aio_reserved[2];
  95   };
  96 #endif
  97
  98
  99 /* Return values of cancelation function.  */
 100 enum
 101 {
 102   AIO_CANCELED,
 103 #define AIO_CANCELED AIO_CANCELED
 104   AIO_NOTCANCELED,
 105 #define AIO_NOTCANCELED AIO_NOTCANCELED
 106   AIO_ALLDONE
 107 #define AIO_ALLDONE AIO_ALLDONE
 108 };
 109
 110
 111 /* Operation codes for `aio_lio_opcode'.  */
 112 enum
 113 {
 114   LIO_READ,
 115 #define LIO_READ LIO_READ
 116   LIO_WRITE,
 117 #define LIO_WRITE LIO_WRITE
 118   LIO_NOP
 119 #define LIO_NOP LIO_NOP
 120 };
 121
 122
 123 /* Synchronization options for `lio_listio' function.  */
 124 enum
 125 {
 126   LIO_WAIT,
 127 #define LIO_WAIT LIO_WAIT
 128   LIO_NOWAIT
 129 #define LIO_NOWAIT LIO_NOWAIT
 130 };
 131
 132
 133 /* Allow user to specify optimization.  */
 134 #ifdef __USE_GNU
 135 extern void aio_init __P ((__const struct aioinit *__init));
 136 #endif
 137
 138
 139 #ifndef __USE_FILE_OFFSET64
 140 /* Enqueue read request for given number of bytes and the given priority.  */
 141 extern int aio_read __P ((struct aiocb *__aiocbp));
 142 /* Enqueue write request for given number of bytes and the given priority.  */
 143 extern int aio_write __P ((struct aiocb *__aiocbp));
 144
 145 /* Initiate list of I/O requests.  */
 146 extern int lio_listio __P ((int __mode, struct aiocb *__const __list[],
 147                             int __nent, struct sigevent *__sig));
 148
 149 /* Retrieve error status associated with AIOCBP.  */
 150 extern int aio_error __P ((__const struct aiocb *__aiocbp));
 151 /* Return status associated with AIOCBP.  */
 152 extern __ssize_t aio_return __P ((struct aiocb *__aiocbp));
 153
 154 /* Try to cancel asynchronous I/O requests outstanding against file
 155    descriptor FILDES.  */
 156 extern int aio_cancel __P ((int __fildes, struct aiocb *__aiocbp));
 157
 158 /* Suspend calling thread until at least one of the asynchronous I/O
 159    operations referenced by LIST has completed.  */
 160 extern int aio_suspend __P ((__const struct aiocb *__const __list[],
 161                              int __nent, __const struct timespec *__timeout));
 162
 163 /* Force all operations associated with file desriptor described by
 164    `aio_fildes' member of AIOCBP.  */
 165 extern int aio_fsync __P ((int __operation, struct aiocb *__aiocbp));
 166 #else
 167 # ifdef __REDIRECT
 168 extern int __REDIRECT (aio_read, __P ((struct aiocb *__aiocbp)), aio_read64);
 169 extern int __REDIRECT (aio_write, __P ((struct aiocb *__aiocbp)), aio_write64);
 170
 171 extern int __REDIRECT (lio_listio, __P ((int __mode,
 172                                          struct aiocb *__const __list[],
 173                                          int __nent, struct sigevent *__sig)),
 174                        lio_listio64);
 175
 176 extern int __REDIRECT (aio_error, __P ((__const struct aiocb *__aiocbp)),
 177                        aio_error64);
 178 extern __ssize_t __REDIRECT (aio_return, __P ((struct aiocb *__aiocbp)),
 179                              aio_return64);
 180
 181 extern int __REDIRECT (aio_cancel, __P ((int __fildes,
 182                                          struct aiocb *__aiocbp)),
 183                        aio_cancel64);
 184
 185 extern int __REDIRECT (aio_suspend,
 186                        __P ((__const struct aiocb *__const __list[],
 187                              int __nent, __const struct timespec *__timeout)),
 188                        aio_suspend64);
 189
 190 extern int __REDIRECT (aio_fsync __P ((int __operation,
 191                                        struct aiocb *__aiocbp)),
 192                        aio_fsync64);
 193
 194 # else
 195 #  define aio_read aio_read64
 196 #  define aio_write aio_write64
 197 #  define lio_listio lio_listio64
 198 #  define aio_error aio_error64
 199 #  define aio_return aio_return64
 200 #  define aio_cancel aio_cancel64
 201 #  define aio_suspend aio_suspend64
 202 #  define aio_fsync aio_fsync64
 203 # endif
 204 #endif
 205
 206 #ifdef __USE_LARGEFILE64
 207 extern int aio_read64 __P ((struct aiocb64 *__aiocbp));
 208 extern int aio_write64 __P ((struct aiocb64 *__aiocbp));
 209
 210 extern int lio_listio64 __P ((int __mode, struct aiocb64 *__const __list[],
 211                               int __nent, struct sigevent *__sig));
 212
 213 extern int aio_error64 __P ((__const struct aiocb64 *__aiocbp));
 214 extern __ssize_t aio_return64 __P ((struct aiocb64 *__aiocbp));
 215
 216 extern int aio_cancel64 __P ((int __fildes, struct aiocb64 *__aiocbp));
 217
 218 extern int aio_suspend64 __P ((__const struct aiocb64 *__const __list[],
 219                                int __nent,
 220                                __const struct timespec *__timeout));
 221
 222 extern int aio_fsync64 __P ((int __operation, struct aiocb64 *__aiocbp));
 223 #endif
 224
 225 __END_DECLS
 226
 227 #endif /* aio.h */