lib/windows-timedrwlock.h

   1 /* Timed read-write locks (native Windows implementation).
   2    Copyright (C) 2019-2024 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as
   6    published by the Free Software Foundation; either version 2.1 of the
   7    License, or (at your option) any later version.
   8
   9    This file 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
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2019.  */
  18
  19 #ifndef _WINDOWS_TIMEDRWLOCK_H
  20 #define _WINDOWS_TIMEDRWLOCK_H
  21
  22 #define WIN32_LEAN_AND_MEAN  /* avoid including junk */
  23 #include <windows.h>
  24
  25 #include <time.h>
  26
  27 #include "windows-initguard.h"
  28
  29 #ifndef _glwthread_linked_waitqueue_link_defined
  30 #define _glwthread_linked_waitqueue_link_defined
  31 struct glwthread_waitqueue_link
  32 {
  33   struct glwthread_waitqueue_link *wql_next;
  34   struct glwthread_waitqueue_link *wql_prev;
  35 };
  36 #endif /* _glwthread_linked_waitqueue_link_defined */
  37 typedef struct
  38         {
  39           struct glwthread_waitqueue_link wq_list; /* circular list of waiting threads */
  40           unsigned int count; /* number of waiting threads */
  41         }
  42         glwthread_clinked_waitqueue_t;
  43
  44 typedef struct
  45         {
  46           glwthread_initguard_t guard; /* protects the initialization */
  47           CRITICAL_SECTION lock; /* protects the remaining fields */
  48           glwthread_clinked_waitqueue_t waiting_readers; /* waiting readers */
  49           glwthread_clinked_waitqueue_t waiting_writers; /* waiting writers */
  50           int runcount; /* number of readers running, or -1 when a writer runs */
  51         }
  52         glwthread_timedrwlock_t;
  53
  54 #define GLWTHREAD_TIMEDRWLOCK_INIT { GLWTHREAD_INITGUARD_INIT }
  55
  56 #ifdef __cplusplus
  57 extern "C" {
  58 #endif
  59
  60 extern void glwthread_timedrwlock_init (glwthread_timedrwlock_t *lock);
  61 extern int glwthread_timedrwlock_rdlock (glwthread_timedrwlock_t *lock);
  62 extern int glwthread_timedrwlock_wrlock (glwthread_timedrwlock_t *lock);
  63 extern int glwthread_timedrwlock_tryrdlock (glwthread_timedrwlock_t *lock);
  64 extern int glwthread_timedrwlock_trywrlock (glwthread_timedrwlock_t *lock);
  65 extern int glwthread_timedrwlock_timedrdlock (glwthread_timedrwlock_t *lock,
  66                                               const struct timespec *abstime);
  67 extern int glwthread_timedrwlock_timedwrlock (glwthread_timedrwlock_t *lock,
  68                                               const struct timespec *abstime);
  69 extern int glwthread_timedrwlock_unlock (glwthread_timedrwlock_t *lock);
  70 extern int glwthread_timedrwlock_destroy (glwthread_timedrwlock_t *lock);
  71
  72 #ifdef __cplusplus
  73 }
  74 #endif
  75
  76 #endif /* _WINDOWS_TIMEDRWLOCK_H */