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
|
/*
* Modification History
*
* 2001-January-11 Jason Rohrer
* Created.
*
* 2001-January-27 Jason Rohrer
* Made printing in threads thread-safe.
*/
#include "BinarySemaphore.h"
#include "Semaphore.h"
#include "Thread.h"
#include "ThreadSafePrinter.h"
#include <stdio.h>
/**
* Thread that waits on a semaphore.
*
* @author Jason Rohrer
*/
class WaitingThread : public Thread {
public:
WaitingThread( int inID, Semaphore *inSemaphore );
// override the run method from PThread
void run();
private:
Semaphore *mSemaphore;
int mID;
};
inline WaitingThread::WaitingThread( int inID, Semaphore *inSemaphore )
: mID( inID ), mSemaphore( inSemaphore ) {
}
inline void WaitingThread::run() {
for( int i=0; i<10; i++ ) {
ThreadSafePrinter::printf( "%d waiting for signal %d...\n", mID, i );
mSemaphore->wait();
ThreadSafePrinter::printf( "%d received signal %d.\n", mID, i );
}
}
/**
* Thread that signals on a semaphore.
*
* @author Jason Rohrer
*/
class SignalingThread : public Thread {
public:
SignalingThread( Semaphore *inSemaphore );
// override the run method from PThread
void run();
private:
Semaphore *mSemaphore;
};
inline SignalingThread::SignalingThread( Semaphore *inSemaphore )
: mSemaphore( inSemaphore ) {
}
inline void SignalingThread::run() {
for( int i=0; i<5; i++ ) {
sleep( 5000 );
ThreadSafePrinter::printf( "Signaling 20 times\n" );
for( int j=0; j<20; j++ ) {
mSemaphore->signal();
}
}
}
int main() {
int i;
Semaphore *semph = new Semaphore();
SignalingThread *threadS = new SignalingThread( semph );
WaitingThread **threadW = new WaitingThread*[10];
for( i=0; i<10; i++ ) {
threadW[i] = new WaitingThread( i, semph );
threadW[i]->start();
}
threadS->start();
for( i=0; i<10; i++ ) {
threadW[i]->join();
delete threadW[i];
}
threadS->join();
delete semph;
delete threadS;
delete [] threadW;
return 0;
}
|
