sc_semaphore.cc revision 13198:5553e3cf7e1f 
1/*
2 * Copyright 2018 Google, Inc.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met: redistributions of source code must retain the above copyright
7 * notice, this list of conditions and the following disclaimer;
8 * redistributions in binary form must reproduce the above copyright
9 * notice, this list of conditions and the following disclaimer in the
10 * documentation and/or other materials provided with the distribution;
11 * neither the name of the copyright holders nor the names of its
12 * contributors may be used to endorse or promote products derived from
13 * this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
19 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * Authors: Gabe Black
28 */
29
30#include "base/logging.hh"
31#include "systemc/ext/channel/sc_semaphore.hh"
32#include "systemc/ext/core/sc_module.hh" // for sc_gen_unique_name
33
34namespace sc_core
35{
36
37sc_semaphore::sc_semaphore(int value) :
38        sc_interface(), sc_semaphore_if(),
39        sc_object(sc_gen_unique_name("semaphore")), _value(value)
40{}
41
42sc_semaphore::sc_semaphore(const char *name, int value) :
43        sc_interface(), sc_semaphore_if(), sc_object(name), _value(value)
44{}
45
46int
47sc_semaphore::wait()
48{
49    while (trywait() == -1)
50        ::sc_core::wait(posted);
51    return 0;
52}
53
54int
55sc_semaphore::trywait()
56{
57    if (!_value)
58        return -1;
59
60    _value--;
61    return 0;
62}
63
64int
65sc_semaphore::post()
66{
67    if (_value++ == 0)
68        posted.notify();
69    return 0;
70}
71
72int sc_semaphore::get_value() const { return _value; }
73
74} // namespace sc_core
75