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 #define __need_timespec
  30 #include <time.h>
  31 #include <sys/types.h>
  32
  33 __BEGIN_DECLS
  34
  35 /* Asynchronous I/O control block.  */
  36 struct aiocb
  37 {
  38   int aio_fildes;               /* File desriptor.  */
  39   int aio_lio_opcode;           /* Operation to be performed.  */
  40   int aio_reqprio;              /* Request priority offset.  */
  41   volatile void *aio_buf;       /* Location of buffer.  */
  42   size_t aio_nbytes;            /* Length of transfer.  */
  43   struct sigevent aio_sigevent; /* Signal number and value.  */
  44
  45   /* Internal members.  */
  46   struct aiocb *__next_prio;
  47   int __abs_prio;
  48   int __policy;
  49   int __error_code;
  50   __ssize_t __return_value;
  51
  52 #ifndef __USE_FILE_OFFSET64
  53   __off_t aio_offset;           /* File offset.  */
  54   char __pad[sizeof (__off64_t) - sizeof (__off_t)];
  55 #else
  56   __off64_t aio_offset;         /* File offset.  */
  57 #endif
  58   char __unused[32];
  59 };
  60
  61 /* The same for the 64bit offsets.  */
  62 #ifdef __USE_LARGEFILE64
  63 struct 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   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 __unused[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.  */
  87 struct 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_reserved[2];
  96   };
  97 #endif
  98
  99
 100 /* Return values of cancelation function.  */
 101 enum
 102 {
 103   AIO_CANCELED,
 104 #define AIO_CANCELED AIO_CANCELED
 105   AIO_NOTCANCELED,
 106 #define AIO_NOTCANCELED AIO_NOTCANCELED
 107   AIO_ALLDONE
 108 #define AIO_ALLDONE AIO_ALLDONE
 109 };
 110
 111
 112 /* Operation codes for `aio_lio_opcode'.  */
 113 enum
 114 {
 115   LIO_READ,
 116 #define LIO_READ LIO_READ
 117   LIO_WRITE,
 118 #define LIO_WRITE LIO_WRITE
 119   LIO_NOP
 120 #define LIO_NOP LIO_NOP
 121 };
 122
 123
 124 /* Synchronization options for `lio_listio' function.  */
 125 enum
 126 {
 127   LIO_WAIT,
 128 #define LIO_WAIT LIO_WAIT
 129   LIO_NOWAIT
 130 #define LIO_NOWAIT LIO_NOWAIT
 131 };
 132
 133
 134 /* Allow user to specify optimization.  */
 135 #ifdef __USE_GNU
 136 extern void __aio_init __P ((__const struct aioinit *__init));
 137 extern void aio_init __P ((__const struct aioinit *__init));
 138 #endif
 139
 140
 141 #ifndef __USE_FILE_OFFSET64
 142 /* Enqueue read request for given number of bytes and the given priority.  */
 143 extern int aio_read __P ((struct aiocb *__aiocbp));
 144 /* Enqueue write request for given number of bytes and the given priority.  */
 145 extern int aio_write __P ((struct aiocb *__aiocbp));
 146
 147 /* Initiate list of I/O requests.  */
 148 extern int lio_listio __P ((int __mode, struct aiocb *__const __list[],
 149                             int __nent, struct sigevent *__sig));
 150
 151 /* Retrieve error status associated with AIOCBP.  */
 152 extern int aio_error __P ((__const struct aiocb *__aiocbp));
 153 /* Return status associated with AIOCBP.  */
 154 extern __ssize_t aio_return __P ((struct aiocb *__aiocbp));
 155
 156 /* Try to cancel asynchronous I/O requests outstanding against file
 157    descriptor FILDES.  */
 158 extern int aio_cancel __P ((int __fildes, struct aiocb *__aiocbp));
 159
 160 /* Suspend calling thread until at least one of the asynchronous I/O
 161    operations referenced by LIST has completed.  */
 162 extern int aio_suspend __P ((__const struct aiocb *__const __list[],
 163                              int __nent, __const struct timespec *__timeout));
 164
 165 /* Force all operations associated with file desriptor described by
 166    `aio_fildes' member of AIOCBP.  */
 167 extern int aio_fsync __P ((int __operation, struct aiocb *__aiocbp));
 168 #else
 169 # ifdef __REDIRECT
 170 extern int __REDIRECT (aio_read, __P ((struct aiocb *__aiocbp)), aio_read64);
 171 extern int __REDIRECT (aio_write, __P ((struct aiocb *__aiocbp)), aio_write64);
 172
 173 extern int __REDIRECT (lio_listio, __P ((int __mode,
 174                                          struct aiocb *__const __list[],
 175                                          int __nent, struct sigevent *__sig)),
 176                        lio_listio64);
 177
 178 extern int __REDIRECT (aio_error, __P ((__const struct aiocb *__aiocbp)),
 179                        aio_error64);
 180 extern __ssize_t __REDIRECT (aio_return, __P ((struct aiocb *__aiocbp)),
 181                              aio_return64);
 182
 183 extern int __REDIRECT (aio_cancel, __P ((int __fildes,
 184                                          struct aiocb *__aiocbp)),
 185                        aio_cancel64);
 186
 187 extern int __REDIRECT (aio_suspend,
 188                        __P ((__const struct aiocb *__const __list[],
 189                              int __nent, __const struct timespec *__timeout)),
 190                        aio_suspend64);
 191
 192 extern int __REDIRECT (aio_fsync __P ((int __operation,
 193                                        struct aiocb *__aiocbp)),
 194                        aio_fsync64);
 195
 196 # else
 197 #  define aio_read aio_read64
 198 #  define aio_write aio_write64
 199 #  define lio_listio lio_listio64
 200 #  define aio_error aio_error64
 201 #  define aio_return aio_return64
 202 #  define aio_cancel aio_cancel64
 203 #  define aio_suspend aio_suspend64
 204 #  define aio_fsync aio_fsync64
 205 # endif
 206 #endif
 207
 208 #ifdef __USE_LARGEFILE64
 209 extern int aio_read64 __P ((struct aiocb64 *__aiocbp));
 210 extern int aio_write64 __P ((struct aiocb64 *__aiocbp));
 211
 212 extern int lio_listio64 __P ((int __mode, struct aiocb64 *__const __list[],
 213                               int __nent, struct sigevent *__sig));
 214
 215 extern int aio_error64 __P ((__const struct aiocb64 *__aiocbp));
 216 extern __ssize_t aio_return64 __P ((struct aiocb64 *__aiocbp));
 217
 218 extern int aio_cancel64 __P ((int __fildes, struct aiocb64 *__aiocbp));
 219
 220 extern int aio_suspend64 __P ((__const struct aiocb64 *__const __list[],
 221                                int __nent,
 222                                __const struct timespec *__timeout));
 223
 224 extern int aio_fsync64 __P ((int __operation, struct aiocb64 *__aiocbp));
 225 #endif
 226
 227 __END_DECLS
 228
 229 #endif /* aio.h */