rt/aio_misc.h

   1 /* Copyright (C) 1997 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 #ifndef _AIO_MISC_H
  20 #define _AIO_MISC_H     1
  21
  22 #include <aio.h>
  23 #include <pthread.h>
  24
  25
  26 /* Extend the operation enum.  */
  27 enum
  28 {
  29   LIO_DSYNC = LIO_READ + 1,
  30   LIO_SYNC,
  31   LIO_READ64 = LIO_READ | 128,
  32   LIO_WRITE64 = LIO_WRITE | 128
  33 };
  34
  35
  36 /* Union of the two request types.  */
  37 typedef union
  38   {
  39     struct aiocb aiocb;
  40     struct aiocb64 aiocb64;
  41   } aiocb_union;
  42
  43
  44 /* Used to synchronize.  */
  45 struct waitlist
  46   {
  47     struct waitlist *next;
  48
  49     pthread_cond_t *cond;
  50     volatile int *counterp;
  51     /* The next field is used in asynchronous `lio_listio' operations.  */
  52     struct sigevent *sigevp;
  53   };
  54
  55
  56 /* Status of a request.  */
  57 enum
  58 {
  59   no,
  60   queued,
  61   yes,
  62   allocated
  63 };
  64
  65
  66 /* Used to queue requests..  */
  67 struct requestlist
  68   {
  69     int running;
  70
  71     struct requestlist *last_fd;
  72     struct requestlist *next_fd;
  73     struct requestlist *next_prio;
  74     struct requestlist *next_run;
  75
  76     /* Pointer to the actual data.  */
  77     aiocb_union *aiocbp;
  78
  79     /* List of waiting processes.  */
  80     struct waitlist *waiting;
  81   };
  82
  83
  84 /* Lock for global I/O list of requests.  */
  85 extern pthread_mutex_t __aio_requests_mutex;
  86
  87
  88 /* Enqueue request.  */
  89 extern struct requestlist *__aio_enqueue_request (aiocb_union *aiocbp,
  90                                                   int operation)
  91      internal_function;
  92
  93 /* Find request entry for given AIO control block.  */
  94 extern struct requestlist *__aio_find_req (aiocb_union *elem)
  95      internal_function;
  96
  97 /* Find request entry for given file descriptor.  */
  98 extern struct requestlist *__aio_find_req_fd (int fildes) internal_function;
  99
 100 /* Release the entry for the request.  */
 101 extern void __aio_free_request (struct requestlist *req) internal_function;
 102
 103 /* Notify initiator of request and tell this everybody listening.  */
 104 extern void __aio_notify (struct requestlist *req) internal_function;
 105
 106 /* Notify initiator of request.  */
 107 extern int __aio_notify_only (struct sigevent *sigev) internal_function;
 108
 109 /* Send the signal.  */
 110 extern int __aio_sigqueue (int sig, const union sigval val) internal_function;
 111
 112 #endif /* aio_misc.h */