1/*
2 * Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#ifndef SHARE_RUNTIME_SEMAPHORE_HPP
26#define SHARE_RUNTIME_SEMAPHORE_HPP
27
28#include "memory/allocation.hpp"
29
30#if defined(LINUX) || defined(SOLARIS) || defined(AIX)
31# include "semaphore_posix.hpp"
32#elif defined(BSD)
33# include "semaphore_bsd.hpp"
34#elif defined(_WINDOWS)
35# include "semaphore_windows.hpp"
36#else
37# error "No semaphore implementation provided for this OS"
38#endif
39
40class JavaThread;
41
42// Implements the limited, platform independent Semaphore API.
43class Semaphore : public CHeapObj<mtSynchronizer> {
44 SemaphoreImpl _impl;
45
46 // Prevent copying and assignment of Semaphore instances.
47 Semaphore(const Semaphore&);
48 Semaphore& operator=(const Semaphore&);
49
50 public:
51 Semaphore(uint value = 0) : _impl(value) {}
52 ~Semaphore() {}
53
54 void signal(uint count = 1) { _impl.signal(count); }
55
56 void wait() { _impl.wait(); }
57
58 bool trywait() { return _impl.trywait(); }
59
60 void wait_with_safepoint_check(JavaThread* thread);
61};
62
63#endif // SHARE_RUNTIME_SEMAPHORE_HPP
64