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tests/lowlevel/mutex/test.c

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+#include <rtapi_mutex.h>
+#include <pthread.h>
+#include <assert.h>
+#include <stdio.h>
+
+// to make this test fail, you can...
+#if 0
+#define rtapi_mutex_give(x) (void)0
+#define rtapi_mutex_get(x) (void)0
+#endif
+
+const unsigned int N = 100000;
+unsigned long mut;
+unsigned long count;
+
+void *thread_fun(void *unused) {
+    for(unsigned long i=0; i<N; i++) {
+        rtapi_mutex_get(&mut);
+            unsigned long tmp = count;
+            tmp++;
+            sched_yield();
+            count = tmp;
+        rtapi_mutex_give(&mut);
+    }
+    return unused;
+}
+
+int main() {
+    pthread_t t1, t2;
+    pthread_create(&t1, NULL, thread_fun, NULL);
+    pthread_create(&t2, NULL, thread_fun, NULL);
+    pthread_join(t1, NULL);
+    pthread_join(t2, NULL);
+    printf("count=%lu\n", count);
+    assert(count == 2*N);
+    printf("test passed\n");
+    return 0;
+}