resolv/gai_misc.h

   1 /* Copyright (C) 2001, 2006 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2001.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _GAI_MISC_H
  21 #define _GAI_MISC_H     1
  22
  23 #include <netdb.h>
  24 #include <signal.h>
  25
  26
  27 /* Used to synchronize.  */
  28 struct waitlist
  29   {
  30     struct waitlist *next;
  31
  32 #ifndef DONT_NEED_GAI_MISC_COND
  33     pthread_cond_t *cond;
  34 #endif
  35     volatile int *counterp;
  36     /* The next field is used in asynchronous `lio_listio' operations.  */
  37     struct sigevent *sigevp;
  38     /* XXX See requestlist, it's used to work around the broken signal
  39        handling in Linux.  */
  40     pid_t caller_pid;
  41   };
  42
  43
  44 /* Used to queue requests..  */
  45 struct requestlist
  46   {
  47     int running;
  48
  49     struct requestlist *next;
  50
  51     /* Pointer to the actual data.  */
  52     struct gaicb *gaicbp;
  53
  54     /* List of waiting processes.  */
  55     struct waitlist *waiting;
  56   };
  57
  58 /* To customize the implementation one can use the following struct.
  59    This implementation follows the one in Irix.  */
  60 struct gaiinit
  61   {
  62     int gai_threads;            /* Maximal number of threads.  */
  63     int gai_num;                /* Number of expected simultanious requests. */
  64     int gai_locks;              /* Not used.  */
  65     int gai_usedba;             /* Not used.  */
  66     int gai_debug;              /* Not used.  */
  67     int gai_numusers;           /* Not used.  */
  68     int gai_idle_time;          /* Number of seconds before idle thread
  69                                    terminates.  */
  70     int gai_reserved;
  71   };
  72
  73
  74 /* Lock for global I/O list of requests.  */
  75 extern pthread_mutex_t __gai_requests_mutex;
  76
  77
  78 /* Enqueue request.  */
  79 extern struct requestlist *__gai_enqueue_request (struct gaicb *gaicbp)
  80      internal_function;
  81
  82 /* Find request on wait list.  */
  83 extern struct requestlist *__gai_find_request (const struct gaicb *gaicbp)
  84      internal_function;
  85
  86 /* Remove request from waitlist.  */
  87 extern int __gai_remove_request (struct gaicb *gaicbp)
  88      internal_function;
  89
  90 /* Notify initiator of request and tell this everybody listening.  */
  91 extern void __gai_notify (struct requestlist *req)
  92      internal_function;
  93
  94 /* Notify initiator of request.  */
  95 extern int __gai_notify_only (struct sigevent *sigev, pid_t caller_pid)
  96      internal_function;
  97
  98 /* Send the signal.  */
  99 extern int __gai_sigqueue (int sig, const union sigval val, pid_t caller_pid)
 100      internal_function;
 101
 102 #endif /* gai_misc.h */