sysdeps/pthread/aio_misc.h

   1 /* Copyright (C) 1997, 1999, 2000, 2001, 2003 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 #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_NOP + 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 #ifdef BROKEN_THREAD_SIGNALS
  54     /* XXX See requestlist, it's used to work around the broken signal
  55        handling in Linux.  */
  56     pid_t caller_pid;
  57 #endif
  58   };
  59
  60
  61 /* Status of a request.  */
  62 enum
  63 {
  64   no,
  65   queued,
  66   yes,
  67   allocated,
  68   done
  69 };
  70
  71
  72 /* Used to queue requests..  */
  73 struct requestlist
  74   {
  75     int running;
  76
  77     struct requestlist *last_fd;
  78     struct requestlist *next_fd;
  79     struct requestlist *next_prio;
  80     struct requestlist *next_run;
  81
  82     /* Pointer to the actual data.  */
  83     aiocb_union *aiocbp;
  84
  85 #ifdef BROKEN_THREAD_SIGNALS
  86     /* PID of the initiator thread.
  87        XXX This is only necessary for the broken signal handling on Linux.  */
  88     pid_t caller_pid;
  89 #endif
  90
  91     /* List of waiting processes.  */
  92     struct waitlist *waiting;
  93   };
  94
  95
  96 /* Lock for global I/O list of requests.  */
  97 extern pthread_mutex_t __aio_requests_mutex attribute_hidden;
  98
  99
 100 /* Enqueue request.  */
 101 extern struct requestlist *__aio_enqueue_request (aiocb_union *aiocbp,
 102                                                   int operation)
 103      attribute_hidden internal_function;
 104
 105 /* Find request entry for given AIO control block.  */
 106 extern struct requestlist *__aio_find_req (aiocb_union *elem)
 107      attribute_hidden internal_function;
 108
 109 /* Find request entry for given file descriptor.  */
 110 extern struct requestlist *__aio_find_req_fd (int fildes)
 111      attribute_hidden internal_function;
 112
 113 /* Remove request from the list.  */
 114 extern void __aio_remove_request (struct requestlist *last,
 115                                   struct requestlist *req, int all)
 116      attribute_hidden internal_function;
 117
 118 /* Release the entry for the request.  */
 119 extern void __aio_free_request (struct requestlist *req)
 120      attribute_hidden internal_function;
 121
 122 /* Notify initiator of request and tell this everybody listening.  */
 123 extern void __aio_notify (struct requestlist *req)
 124      attribute_hidden internal_function;
 125
 126 /* Notify initiator of request.  */
 127 #ifdef BROKEN_THREAD_SIGNALS
 128 extern int __aio_notify_only (struct sigevent *sigev, pid_t caller_pid)
 129      attribute_hidden internal_function;
 130 #else
 131 extern int __aio_notify_only (struct sigevent *sigev)
 132      attribute_hidden internal_function;
 133 #endif
 134
 135 /* Send the signal.  */
 136 extern int __aio_sigqueue (int sig, const union sigval val, pid_t caller_pid)
 137      attribute_hidden internal_function;
 138
 139 #endif /* aio_misc.h */