Ajout de l'exo 1 TP4

TP4/Exo1/helpers.c

@@ -0,0 +1,19 @@
+#include "helpers.h"
+#include <signal.h>
+#include <time.h>
+
+int set_signal_handler(int signo, void (*handler)(int)) {
+    struct sigaction sa;
+    sa.sa_handler = handler;    // call `handler` on signal
+    sigemptyset(&sa.sa_mask);   // don't block other signals in handler
+    sa.sa_flags = SA_RESTART;            //  restart system calls
+    return sigaction(signo, &sa, NULL);
+}
+
+double tstamp(void) {                                                                                    
+	struct timespec tv;
+	clock_gettime(CLOCK_REALTIME, &tv);
+	return tv.tv_sec + tv.tv_nsec * 1.0e-9;
+}
+
+

TP4/Exo1/helpers.h

@@ -0,0 +1,7 @@
+#ifndef _HELPERS_H
+#define _HELPERS_H
+
+int set_signal_handler(int signo, void (*handler)(int));
+double tstamp(void);
+
+#endif

TP4/Exo1/pi.c

@@ -0,0 +1,67 @@
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <stdint.h>
+#include <assert.h>
+#include "helpers.h"
+#include "helpers.c"
+
+uint64_t shots = 0,
+		 shots_in = 0;
+
+double pi = 0,
+	   t1;
+
+void alarm_handler(int)
+{
+	printf("pi = %f\n", pi);
+	printf("le nombre de tirs est de %f\n", (double)shots);
+	alarm(5);
+}
+
+void int_handler(int)
+{
+	char c;
+
+	alarm(0);
+	printf("Voulez-vous quitter ? (y/n)\n");
+	c = getchar();
+
+	if (c == 'y' || c == 'Y')
+	{
+		printf("Le temps écoulé est de %f\n", tstamp() - t1);
+		exit(0);
+	}
+
+	alarm(5);
+}
+
+void quit_handler(int)
+{
+	shots = 0;
+	shots_in = 0;
+	t1 = tstamp();
+}
+
+int main(int argc, char *argv[])
+{
+	double x, y;
+	t1 = tstamp();
+	alarm(5);
+	set_signal_handler(SIGALRM, &alarm_handler);
+	set_signal_handler(SIGINT, &int_handler);
+	set_signal_handler(SIGQUIT, &quit_handler);
+
+	while (1)
+	{
+		x = ((double)rand()) / (double)RAND_MAX;
+		y = ((double)rand()) / (double)RAND_MAX;
+		shots++;
+
+		if ((x * x + y * y) <= 1)
+			shots_in++;
+		
+		pi = 4 * (double)(shots_in) / shots;
+	}
+}