JackPosixSemaphore.cpp 5.4 KB
Newer Older
sletz's avatar
sletz committed
1
/*
sletz's avatar
sletz committed
2
Copyright (C) 2004-2008 Grame  
sletz's avatar
sletz committed
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20

This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program 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 General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include "JackPosixSemaphore.h"
sletz's avatar
sletz committed
21
#include "JackConstants.h"
sletz's avatar
sletz committed
22
23
24
25
26
27
28
#include "JackError.h"
#include <fcntl.h>
#include <sys/time.h>

namespace Jack
{

29
void JackPosixSemaphore::BuildName(const char* name, const char* server_name, char* res)
sletz's avatar
sletz committed
30
{
31
    sprintf(res, "%s/jack_sem.%s_%s", jack_client_dir, server_name, name);
sletz's avatar
sletz committed
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
}

bool JackPosixSemaphore::Signal()
{
    int res;
    assert(fSemaphore);

    if (fFlush)
        return true;

    if ((res = sem_post(fSemaphore)) != 0) {
        jack_error("JackPosixSemaphore::Signal name = %s err = %s", fName, strerror(errno));
    }
    return (res == 0);
}

bool JackPosixSemaphore::SignalAll()
{
    int res;
    assert(fSemaphore);

    if (fFlush)
        return true;

    if ((res = sem_post(fSemaphore)) != 0) {
        jack_error("JackPosixSemaphore::SignalAll name = %s err = %s", fName, strerror(errno));
    }
    return (res == 0);
}

/*
bool JackPosixSemaphore::Wait()
{
    int res;
	assert(fSemaphore);
    if ((res = sem_wait(fSemaphore)) != 0) {
        jack_error("JackPosixSemaphore::Wait name = %s err = %s", fName, strerror(errno));
    }
    return (res == 0);
}
*/

bool JackPosixSemaphore::Wait()
{
    int res;

    while ((res = sem_wait(fSemaphore) < 0)) {
        jack_error("JackPosixSemaphore::Wait name = %s err = %s", fName, strerror(errno));
        if (errno != EINTR)
            break;
    }
    return (res == 0);
}


/*
#ifdef __linux__
 
bool JackPosixSemaphore::TimedWait(long usec) // unusable semantic !!
{
	int res;
	struct timeval now;
	timespec time;
	assert(fSemaphore);
	gettimeofday(&now, 0);
	time.tv_sec = now.tv_sec + usec / 1000000;
	time.tv_nsec = (now.tv_usec + (usec % 1000000)) * 1000;
	
    if ((res = sem_timedwait(fSemaphore, &time)) != 0) {
        jack_error("JackPosixSemaphore::TimedWait err = %s", strerror(errno));
		JackLog("now %ld %ld \n", now.tv_sec, now.tv_usec);
		JackLog("next %ld %ld \n", time.tv_sec, time.tv_nsec/1000);
	}
    return (res == 0);
}
 
#else 
#warning "JackPosixSemaphore::TimedWait is not supported: Jack in SYNC mode with JackPosixSemaphore will not run properly !!"
 
bool JackPosixSemaphore::TimedWait(long usec)
{
	return Wait();
}
#endif 
*/

#warning JackPosixSemaphore::TimedWait not available : synchronous mode may not work correctly if POSIX semaphore are used

bool JackPosixSemaphore::TimedWait(long usec)
{
    return Wait();
}

// Server side : publish the semaphore in the global namespace
126
bool JackPosixSemaphore::Allocate(const char* name, const char* server_name, int value)
sletz's avatar
sletz committed
127
{
128
    BuildName(name, server_name, fName);
sletz's avatar
sletz committed
129
130
131
132
133
134
135
136
137
138
139
    JackLog("JackPosixSemaphore::Allocate name = %s val = %ld\n", fName, value);

    if ((fSemaphore = sem_open(fName, O_CREAT, 0777, value)) == (sem_t*)SEM_FAILED) {
        jack_error("Allocate: can't check in named semaphore name = %s err = %s", fName, strerror(errno));
        return false;
    } else {
        return true;
    }
}

// Client side : get the published semaphore from server
140
bool JackPosixSemaphore::ConnectInput(const char* name, const char* server_name)
sletz's avatar
sletz committed
141
{
142
    BuildName(name, server_name, fName);
sletz's avatar
sletz committed
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
    JackLog("JackPosixSemaphore::Connect %s\n", fName);

    // Temporary...
    if (fSemaphore) {
        JackLog("Already connected name = %s\n", name);
        return true;
    }

    if ((fSemaphore = sem_open(fName, O_CREAT)) == (sem_t*)SEM_FAILED) {
        jack_error("Connect: can't connect named semaphore name = %s err = %s", fName, strerror(errno));
        return false;
    } else {
        int val = 0;
        sem_getvalue(fSemaphore, &val);
        JackLog("JackPosixSemaphore::Connect sem_getvalue %ld\n", val);
        return true;
    }
}

162
bool JackPosixSemaphore::Connect(const char* name, const char* server_name)
sletz's avatar
sletz committed
163
{
164
    return ConnectInput(name, server_name);
sletz's avatar
sletz committed
165
166
}

167
bool JackPosixSemaphore::ConnectOutput(const char* name, const char* server_name)
sletz's avatar
sletz committed
168
{
169
    return ConnectInput(name, server_name);
sletz's avatar
sletz committed
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
}

bool JackPosixSemaphore::Disconnect()
{
    JackLog("JackPosixSemaphore::Disconnect %s\n", fName);

    if (fSemaphore) {
        if (sem_close(fSemaphore) != 0) {
            jack_error("Disconnect: can't disconnect named semaphore name = %s err = %s", fName, strerror(errno));
            return false;
        } else {
            fSemaphore = NULL;
            return true;
        }
    } else {
        return true;
    }
}

// Server side : destroy the semaphore
void JackPosixSemaphore::Destroy()
{
    if (fSemaphore != NULL) {
        JackLog("JackPosixSemaphore::Destroy\n");
        sem_unlink(fName);
        if (sem_close(fSemaphore) != 0) {
            jack_error("Destroy: can't destroy semaphore name = %s err = %s", fName, strerror(errno));
        }
        fSemaphore = NULL;
    } else {
        jack_error("JackPosixSemaphore::Destroy semaphore == NULL");
    }
}

} // end of namespace