summaryrefslogtreecommitdiff
path: root/src/semaphore.cc
blob: 77bce9a551a849526b70761549f9c4937b44465f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            semaphore.cc
 *
 *  Sat Oct  8 17:44:13 CEST 2005
 *  Copyright  2005 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of DrumGizmo.
 *
 *  DrumGizmo 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 3 of the License, or
 *  (at your option) any later version.
 *
 *  DrumGizmo 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 DrumGizmo; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "semaphore.h"

#include <hugin.hpp>
#include <limits>
#include <assert.h>
#include <string.h>

#include "platform.h"

#if DG_PLATFORM == DG_PLATFORM_OSX
//#include <Multiprocessing.h>
#include <CoreServices/CoreServices.h>

#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
#include <sys/types.h>
#include <sys/lock.h>
#include <sys/sema.h>

#elif DG_PLATFORM != DG_PLATFORM_WINDOWS
// Make sure we don't include /this/ file's header...
#include <../include/semaphore.h>
#include <errno.h>
#include <stdio.h>
#include <sys/time.h>
#endif

struct semaphore_private_t {
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
	HANDLE semaphore;
#elif DG_PLATFORM == DG_PLATFORM_OSX
	MPSemaphoreID semaphore;
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
	struct sema *semaphore;
#else
	sem_t semaphore;
#endif
};

Semaphore::Semaphore(std::size_t initial_count)
{
	prv = new struct semaphore_private_t();

#if DG_PLATFORM == DG_PLATFORM_WINDOWS
	prv->semaphore = CreateSemaphore(nullptr,  // default security attributes
	                                 initial_count,
	                                 std::numeric_limits<LONG>::max(),
	                                 nullptr); // unnamed semaphore
#elif DG_PLATFORM == DG_PLATFORM_OSX
	MPCreateSemaphore(std::numeric_limits<std::uint32_t>::max(),
	                  initial_count,
	                  &prv->semaphore);
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
	sema_init(prv->semaphore, initial_count, "");
#else
	const int pshared = 0;
	memset(&prv->semaphore, 0, sizeof(sem_t));
	sem_init(&prv->semaphore, pshared, initial_count);
#endif
}

Semaphore::~Semaphore()
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
	CloseHandle(prv->semaphore);
#elif DG_PLATFORM == DG_PLATFORM_OSX
	MPDeleteSemaphore(prv->semaphore);
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
#else
	sem_destroy(&prv->semaphore);
#endif

	delete prv;
}

void Semaphore::post()
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
	ReleaseSemaphore(prv->semaphore, 1, nullptr);
#elif DG_PLATFORM == DG_PLATFORM_OSX
	MPSignalSemaphore(prv->semaphore);
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
	sema_destroy(prv->semaphore)
#else
	sem_post(&prv->semaphore);
#endif
}

bool Semaphore::wait(const std::chrono::milliseconds& timeout)
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
	DWORD ret = WaitForSingleObject(prv->semaphore, timeout.count());
	if(ret == WAIT_TIMEOUT)
	{
		return false;
	}

	assert(ret == WAIT_OBJECT_0);
#elif DG_PLATFORM == DG_PLATFORM_OSX
	auto ret = MPWaitOnSemaphore(prv->semaphore,
	                             kDurationMillisecond * timeout.count());
	if(ret == kMPTimeoutErr)
	{
		return false;
	}
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
	auto ret = sema_timedwait(prv->semaphore, timeout.count());
	if(ret != 0)
	{
		return false;
	}
#else
	struct timespec ts;

	struct timeval now;
	int rv = gettimeofday(&now, nullptr);
	assert(rv == 0);

	ts.tv_sec  = now.tv_sec;
	ts.tv_nsec = now.tv_usec * 1000;

	// Add timeout
	time_t seconds = (time_t)(timeout.count() / 1000);
	ts.tv_sec += seconds;
	ts.tv_nsec += (long)((timeout.count() - (seconds * 1000)) * 1000000);

	// Make sure we don't overflow the nanoseconds.
	constexpr long nsec = 1000000000LL;
	if(ts.tv_nsec >= nsec)
	{
		ts.tv_nsec -= nsec;
		ts.tv_sec += 1;
	}

	int ret = sem_timedwait(&prv->semaphore, &ts);
	if(ret < 0)
	{
		if(errno == ETIMEDOUT)
		{
			return false;
		}

		perror("sem_timedwait()");
		assert(false);
	}
#endif

	return true;
}

void Semaphore::wait()
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
	WaitForSingleObject(prv->semaphore, INFINITE);
#elif DG_PLATFORM == DG_PLATFORM_OSX
	MPWaitOnSemaphore(prv->semaphore, kDurationForever);
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
	sema_wait(prv->semaphore);
#else
	sem_wait(&prv->semaphore);
#endif
}