sysdeps/pthread/aio_misc.h

   1 /* Copyright (C) 1997,1999,2000,2001,2003,2006 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     /* The next two fields is used in synchronous `lio_listio' operations.  */
  50 #ifndef DONT_NEED_AIO_MISC_COND
  51     pthread_cond_t *cond;
  52 #endif
  53     int *result;
  54
  55     volatile int *counterp;
  56     /* The next field is used in asynchronous `lio_listio' operations.  */
  57     struct sigevent *sigevp;
  58 #ifdef BROKEN_THREAD_SIGNALS
  59     /* XXX See requestlist, it's used to work around the broken signal
  60        handling in Linux.  */
  61     pid_t caller_pid;
  62 #endif
  63   };
  64
  65
  66 /* Status of a request.  */
  67 enum
  68 {
  69   no,
  70   queued,
  71   yes,
  72   allocated,
  73   done
  74 };
  75
  76
  77 /* Used to queue requests..  */
  78 struct requestlist
  79   {
  80     int running;
  81
  82     struct requestlist *last_fd;
  83     struct requestlist *next_fd;
  84     struct requestlist *next_prio;
  85     struct requestlist *next_run;
  86
  87     /* Pointer to the actual data.  */
  88     aiocb_union *aiocbp;
  89
  90 #ifdef BROKEN_THREAD_SIGNALS
  91     /* PID of the initiator thread.
  92        XXX This is only necessary for the broken signal handling on Linux.  */
  93     pid_t caller_pid;
  94 #endif
  95
  96     /* List of waiting processes.  */
  97     struct waitlist *waiting;
  98   };
  99
 100
 101 /* Lock for global I/O list of requests.  */
 102 extern pthread_mutex_t __aio_requests_mutex attribute_hidden;
 103
 104
 105 /* Enqueue request.  */
 106 extern struct requestlist *__aio_enqueue_request (aiocb_union *aiocbp,
 107                                                   int operation)
 108      attribute_hidden internal_function;
 109
 110 /* Find request entry for given AIO control block.  */
 111 extern struct requestlist *__aio_find_req (aiocb_union *elem)
 112      attribute_hidden internal_function;
 113
 114 /* Find request entry for given file descriptor.  */
 115 extern struct requestlist *__aio_find_req_fd (int fildes)
 116      attribute_hidden internal_function;
 117
 118 /* Remove request from the list.  */
 119 extern void __aio_remove_request (struct requestlist *last,
 120                                   struct requestlist *req, int all)
 121      attribute_hidden internal_function;
 122
 123 /* Release the entry for the request.  */
 124 extern void __aio_free_request (struct requestlist *req)
 125      attribute_hidden internal_function;
 126
 127 /* Notify initiator of request and tell this everybody listening.  */
 128 extern void __aio_notify (struct requestlist *req)
 129      attribute_hidden internal_function;
 130
 131 /* Notify initiator of request.  */
 132 #ifdef BROKEN_THREAD_SIGNALS
 133 extern int __aio_notify_only (struct sigevent *sigev, pid_t caller_pid)
 134      attribute_hidden internal_function;
 135 #else
 136 extern int __aio_notify_only (struct sigevent *sigev)
 137      attribute_hidden internal_function;
 138 #endif
 139
 140 /* Send the signal.  */
 141 extern int __aio_sigqueue (int sig, const union sigval val, pid_t caller_pid)
 142      attribute_hidden internal_function;
 143
 144 #endif /* aio_misc.h */