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authorJörg Frings-Fürst <debian@jff.email>2022-02-07 06:57:44 +0100
committerJörg Frings-Fürst <debian@jff.email>2022-02-07 06:57:44 +0100
commit6ffaa52cf732a84c0f8259dbc9b8183960ec5c33 (patch)
treed3136c22e3e805cfc0efe78412cce905a17e0c8d /lib/windows-rwlock.h
parent591cbf5878b7d4105b275585b9db1324c9dfce56 (diff)
parentaf151c593704a40e10efb28d1e3dd59a23a661f3 (diff)
Merge branch 'release/debian/1.0-1'debian/1.0-1
Diffstat (limited to 'lib/windows-rwlock.h')
-rw-r--r--lib/windows-rwlock.h68
1 files changed, 68 insertions, 0 deletions
diff --git a/lib/windows-rwlock.h b/lib/windows-rwlock.h
new file mode 100644
index 00000000..65c5ab49
--- /dev/null
+++ b/lib/windows-rwlock.h
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+/* Read-write locks (native Windows implementation).
+ Copyright (C) 2005-2022 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ This file is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2005.
+ Based on GCC's gthr-win32.h. */
+
+#ifndef _WINDOWS_RWLOCK_H
+#define _WINDOWS_RWLOCK_H
+
+#define WIN32_LEAN_AND_MEAN /* avoid including junk */
+#include <windows.h>
+
+#include "windows-initguard.h"
+
+/* It is impossible to implement read-write locks using plain locks, without
+ introducing an extra thread dedicated to managing read-write locks.
+ Therefore here we need to use the low-level Event type. */
+
+typedef struct
+ {
+ HANDLE *array; /* array of waiting threads, each represented by an event */
+ unsigned int count; /* number of waiting threads */
+ unsigned int alloc; /* length of allocated array */
+ unsigned int offset; /* index of first waiting thread in array */
+ }
+ glwthread_carray_waitqueue_t;
+typedef struct
+ {
+ glwthread_initguard_t guard; /* protects the initialization */
+ CRITICAL_SECTION lock; /* protects the remaining fields */
+ glwthread_carray_waitqueue_t waiting_readers; /* waiting readers */
+ glwthread_carray_waitqueue_t waiting_writers; /* waiting writers */
+ int runcount; /* number of readers running, or -1 when a writer runs */
+ }
+ glwthread_rwlock_t;
+
+#define GLWTHREAD_RWLOCK_INIT { GLWTHREAD_INITGUARD_INIT }
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern void glwthread_rwlock_init (glwthread_rwlock_t *lock);
+extern int glwthread_rwlock_rdlock (glwthread_rwlock_t *lock);
+extern int glwthread_rwlock_wrlock (glwthread_rwlock_t *lock);
+extern int glwthread_rwlock_tryrdlock (glwthread_rwlock_t *lock);
+extern int glwthread_rwlock_trywrlock (glwthread_rwlock_t *lock);
+extern int glwthread_rwlock_unlock (glwthread_rwlock_t *lock);
+extern int glwthread_rwlock_destroy (glwthread_rwlock_t *lock);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _WINDOWS_RWLOCK_H */