sc_semaphore.cc revision 13324:c8b709468e61 
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 <string>
31
32#include "base/logging.hh"
33#include "systemc/ext/channel/messages.hh"
34#include "systemc/ext/channel/sc_semaphore.hh"
35#include "systemc/ext/core/sc_module.hh" // for sc_gen_unique_name
36#include "systemc/ext/utils/sc_report_handler.hh"
37
38namespace sc_core
39{
40
41sc_semaphore::sc_semaphore(int value) :
42    sc_semaphore(sc_gen_unique_name("semaphore"), value)
43{}
44
45sc_semaphore::sc_semaphore(const char *_name, int value) :
46        sc_interface(), sc_semaphore_if(), sc_object(_name), _value(value)
47{
48    if (value < 0) {
49        std::string msg = "semaphore '" + std::string(name()) + "'";
50        SC_REPORT_ERROR(SC_ID_INVALID_SEMAPHORE_VALUE_, msg.c_str());
51    }
52}
53
54int
55sc_semaphore::wait()
56{
57    while (trywait() == -1)
58        ::sc_core::wait(posted);
59    return 0;
60}
61
62int
63sc_semaphore::trywait()
64{
65    if (!_value)
66        return -1;
67
68    _value--;
69    return 0;
70}
71
72int
73sc_semaphore::post()
74{
75    if (_value++ == 0)
76        posted.notify();
77    return 0;
78}
79
80int sc_semaphore::get_value() const { return _value; }
81
82} // namespace sc_core
83