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
|
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
* sem.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 "sem.h"
#include <hugin.hpp>
#include <limits>
#include <assert.h>
#include <string.h>
#include <chrono>
#include <thread>
#include "platform.h"
#if DG_PLATFORM != DG_PLATFORM_WINDOWS
#include <semaphore.h>
#include <errno.h>
#include <stdio.h>
#include <sys/time.h>
#endif
#if DG_PLATFORM == DG_PLATFORM_OSX
//#include <Multiprocessing.h>
#include <CoreServices/CoreServices.h>
#endif
struct semaphore_private_t {
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
HANDLE semaphore;
#elif DG_PLATFORM == DG_PLATFORM_OSX
MPSemaphoreID 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);
#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);
#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);
#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;
}
#else
struct timespec ts;
clock_gettime(CLOCK_REALTIME, &ts);
// Add timeout
time_t seconds = (time_t)(timeout.count() / 1000);
ts.tv_sec += seconds;
ts.tv_nsec += (long)((timeout.count() % 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;
}
again:
int ret = sem_timedwait(&prv->semaphore, &ts);
if(ret < 0)
{
if(errno == EINTR)
{
// The timed wait were interrupted prematurely so we need to wait some
// more. To prevent an infinite loop-like behaviour we make a short sleep.
std::this_thread::sleep_for(std::chrono::milliseconds(1));
goto again;
}
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);
#else
again:
int ret = sem_wait(&prv->semaphore);
if(ret < 0)
{
if(errno == EINTR)
{
// The wait were interrupted prematurely so we need to wait again
// To prevent an infinite loop-like behaviour we make a short sleep.
std::this_thread::sleep_for(std::chrono::milliseconds(1));
goto again;
}
perror("sem_wait()");
assert(false);
}
#endif
}
|
