tsdwl: add exam

1 files changed, 72 insertions, 0 deletions

diff --git a/Year_3/TSDWL/ex_20191218/thread.c b/Year_3/TSDWL/ex_20191218/thread.c
new file mode 100644
index 0000000..7d77646
--- /dev/null
+++ b/Year_3/TSDWL/ex_20191218/thread.c
@@ -0,0 +1,72 @@
+#include <pthread.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <time.h>
+#include <math.h>
+
+int x;
+pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+pthread_cond_t cond;
+
+void*
+t1_fn(void* arg)
+{
+    int m;
+
+    while (1) {
+        usleep(100 * 1000);
+        m = rand() % 11;
+
+        pthread_mutex_lock(&mutex);
+        printf("th1: (x=%d, m=%d):", x, m);
+        if (x == -1) {
+            break;
+        } else if (x == m) {
+            printf("RISPOSTA CORRETTA\n");
+            x = -1;
+            break;
+        } else if (abs(x-m) > 5) {
+            printf("risposta MOLTO sbagliata\n");
+            pthread_mutex_unlock(&mutex);
+            pthread_cond_wait(&cond, &mutex);
+        } else {
+            printf("risposta sbagliata\n");
+        }
+        pthread_mutex_unlock(&mutex);
+    }
+
+    pthread_mutex_unlock(&mutex);
+    pthread_exit(NULL);
+}
+
+void*
+t2_fn(void* arg)
+{
+    while (1) {
+        usleep(300* 1000);
+        pthread_mutex_lock(&mutex);
+        printf("\tthread 2 %d\n", x);
+        if (x == -1) {
+            pthread_mutex_unlock(&mutex);
+            pthread_exit(NULL);
+        }
+        pthread_cond_signal(&cond);
+        pthread_mutex_unlock(&mutex);
+    }
+}
+
+int
+main()
+{
+    pthread_t t1, t2;
+    srand(time(NULL));
+    x = rand() % 11;
+
+    pthread_create(&t1, NULL, t1_fn, NULL);
+    pthread_create(&t2, NULL, t2_fn, NULL);
+    pthread_join(t1, NULL);
+    pthread_join(t2, NULL);
+
+    return 0;
+}