1 /// Qt4 semaphore test. 2 3 #ifndef _GNU_SOURCE 4 #define _GNU_SOURCE 5 #endif 6 7 #include <QThread> // class QMutex 8 #include <QSemaphore> // class QSemaphore 9 #include <cstdio> // fprintf() 10 #include <cstdlib> // atoi() 11 #include <new> 12 #include <pthread.h> // pthread_barrier_t 13 #include <vector> 14 15 16 static pthread_barrier_t s_barrier; 17 static QSemaphore* s_pSema; 18 static int s_iterations; 19 static int s_counter; 20 21 22 class IncThread: public QThread 23 { 24 virtual void run(); 25 }; 26 27 void IncThread::run() 28 { 29 int i; 30 31 pthread_barrier_wait(&s_barrier); 32 for (i = s_iterations; i > 0; i--) 33 { 34 s_pSema->acquire(); 35 s_counter++; 36 s_pSema->release(); 37 } 38 } 39 40 int main(int argc, char** argv) 41 { 42 int i; 43 const int n_threads = 10; 44 std::vector<QThread*> tid(n_threads); 45 46 s_iterations = argc > 1 ? atoi(argv[1]) : 1000; 47 48 fprintf(stderr, "Start of test.\n"); 49 50 { 51 // Stack-allocated semaphore. 52 QSemaphore S(1); 53 S.acquire(); 54 S.release(); 55 S.acquire(); 56 S.release(); 57 } 58 59 pthread_barrier_init(&s_barrier, 0, n_threads); 60 s_pSema = new QSemaphore(1); 61 for (i = 0; i < n_threads; i++) 62 { 63 tid[i] = new IncThread; 64 tid[i]->start(); 65 } 66 for (i = 0; i < n_threads; i++) 67 { 68 tid[i]->wait(); 69 delete tid[i]; 70 } 71 delete s_pSema; 72 s_pSema = 0; 73 pthread_barrier_destroy(&s_barrier); 74 75 if (s_counter == n_threads * s_iterations) 76 fprintf(stderr, "Test successful.\n"); 77 else 78 fprintf(stderr, "Test failed: counter = %d, should be %d\n", 79 s_counter, n_threads * s_iterations); 80 81 return 0; 82 } 83
