myvtm/Framework/libtoolkit/test/test_lock.cpp

#include <stdio.h>
#include <toolkit.h>

toolkit_barrier_t blocker;
toolkit_rwlock_t numlock;
int shared_num;

void reader(void* n)
{
    int num = *(int*)n;
    int i;
    for (i = 0; i < 20; i++) {
        toolkit_rwlock_rdlock(&numlock);
        printf("Reader %d: acquired lock\n", num);
        printf("Reader %d: shared num = %d\n", num, shared_num);
        toolkit_rwlock_rdunlock(&numlock);
        printf("Reader %d: released lock\n", num);
    }
    toolkit_barrier_wait(&blocker);
}

void writer(void* n)
{
    int num = *(int*)n;
    int i;
    for (i = 0; i < 20; i++) {
        toolkit_rwlock_wrlock(&numlock);
        printf("Writer %d: acquired lock\n", num);
        shared_num++;
        printf("Writer %d: incremented shared num = %d\n", num, shared_num);
        toolkit_rwlock_wrunlock(&numlock);
        printf("Writer %d: released lock\n", num);
    }
    toolkit_barrier_wait(&blocker);
}

int main()
{
    toolkit_barrier_init(&blocker, 4);

    shared_num = 0;
    toolkit_rwlock_init(&numlock);

    toolkit_thread_t threads[3];

    int thread_nums[] = { 1, 2, 1 };
    toolkit_thread_create(&threads[0], reader, &thread_nums[0]);
    toolkit_thread_create(&threads[1], reader, &thread_nums[1]);

    toolkit_thread_create(&threads[2], writer, &thread_nums[2]);

    toolkit_barrier_wait(&blocker);
    toolkit_barrier_destroy(&blocker);

    toolkit_rwlock_destroy(&numlock);
    return 0;
}