1  /* Copyright (C) 2001-2023 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, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #ifndef _GAI_MISC_H
      19  #define _GAI_MISC_H	1
      20  
      21  #include <netdb.h>
      22  #include <signal.h>
      23  
      24  
      25  /* Used to synchronize.  */
      26  struct waitlist
      27    {
      28      struct waitlist *next;
      29  
      30  #ifndef DONT_NEED_GAI_MISC_COND
      31      pthread_cond_t *cond;
      32  #endif
      33      volatile unsigned int *counterp;
      34      /* The next field is used in asynchronous `lio_listio' operations.  */
      35      struct sigevent *sigevp;
      36      /* XXX See requestlist, it's used to work around the broken signal
      37         handling in Linux.  */
      38      pid_t caller_pid;
      39    };
      40  
      41  
      42  /* Used to queue requests..  */
      43  struct requestlist
      44    {
      45      int running;
      46  
      47      struct requestlist *next;
      48  
      49      /* Pointer to the actual data.  */
      50      struct gaicb *gaicbp;
      51  
      52      /* List of waiting processes.  */
      53      struct waitlist *waiting;
      54    };
      55  
      56  /* To customize the implementation one can use the following struct.
      57     This implementation follows the one in Irix.  */
      58  struct gaiinit
      59    {
      60      int gai_threads;		/* Maximal number of threads.  */
      61      int gai_num;		/* Number of expected simultaneous requests. */
      62      int gai_locks;		/* Not used.  */
      63      int gai_usedba;		/* Not used.  */
      64      int gai_debug;		/* Not used.  */
      65      int gai_numusers;		/* Not used.  */
      66      int gai_idle_time;		/* Number of seconds before idle thread
      67  				   terminates.  */
      68      int gai_reserved;
      69    };
      70  
      71  
      72  /* Lock for global I/O list of requests.  */
      73  extern pthread_mutex_t __gai_requests_mutex;
      74  
      75  
      76  /* Enqueue request.  */
      77  extern struct requestlist *__gai_enqueue_request (struct gaicb *gaicbp)
      78       attribute_hidden;
      79  
      80  /* Find request on wait list.  */
      81  extern struct requestlist *__gai_find_request (const struct gaicb *gaicbp)
      82       attribute_hidden;
      83  
      84  /* Remove request from waitlist.  */
      85  extern int __gai_remove_request (struct gaicb *gaicbp)
      86       attribute_hidden;
      87  
      88  /* Notify initiator of request and tell this everybody listening.  */
      89  extern void __gai_notify (struct requestlist *req)
      90       attribute_hidden;
      91  
      92  /* Notify initiator of request.  */
      93  extern int __gai_notify_only (struct sigevent *sigev, pid_t caller_pid)
      94       attribute_hidden;
      95  
      96  /* Send the signal.  */
      97  extern int __gai_sigqueue (int sig, const union sigval val, pid_t caller_pid);
      98  libc_hidden_proto (__gai_sigqueue)
      99  
     100  #endif /* gai_misc.h */