add: time display

src/main.c

@@ -11,7 +11,7 @@
 #include <arpa/inet.h>
 #include <unistd.h>
 #include <fcntl.h>
-#include <time.h>
+#include <sys/time.h>
 
 void print_err(const char *format, ...)
 {
@@ -155,15 +155,30 @@ int main(int ac, char **av)
     dest.sin_port = htons(0);       
     inet_pton(AF_INET, "8.8.8.8", &dest.sin_addr);
 
+    char *packet = create_packet(payload_size);
+    if (packet == NULL)
+    {
+        close(sockfd);
+        return 2;
+    }
+
+    char *buffer;
+    buffer = malloc(packet_size * sizeof(char));
+    if (buffer == NULL)
+    {
+        print_err("error: allocation failed.");
+        free(packet);
+        close(sockfd);
+        return 10;
+    }
+    struct sockaddr_in sender;
+    socklen_t len = sizeof(sender); 
+
     while (1) {
 
-        char *packet = create_packet(payload_size);
+        struct timeval stop, start;
-        if (packet == NULL)
-        {
-            close(sockfd);
-            return 2;
-        }
 
+        gettimeofday(&start, NULL);
         if (sendto(sockfd, packet, packet_size, 0,  (struct sockaddr *) &dest, sizeof(dest)) == -1)
         {
             print_err("error: send packet failed.");
@@ -173,18 +188,6 @@ int main(int ac, char **av)
         }
         printf("icmp request sent\n");
 
-        char *buffer;
-        buffer = malloc(packet_size * sizeof(char));
-        if (buffer == NULL)
-        {
-            print_err("error: allocation failed.");
-            free(packet);
-            close(sockfd);
-            return 10;
-        }
-        struct sockaddr_in sender;
-        socklen_t len = sizeof(sender); 
-
         do
         {
             if (recvfrom(sockfd, buffer, packet_size, 0, (struct sockaddr *) &sender, &len) < 0)
@@ -195,10 +198,17 @@ int main(int ac, char **av)
                 free(packet);
                 return 3;
             }
+            gettimeofday(&stop, NULL);
         }
         while (len == packet_size && packet_check(buffer, packet_size) == 0 && pktcmp(packet, buffer, packet_size) == 0);
-        free(packet);
+
-        printf("icmp reply received\n");
+        double time_interval = ((stop.tv_sec - start.tv_sec) * 1000 + (stop.tv_usec - start.tv_usec)) / 1000;
+        printf("icmp reply received %fms\n", time_interval);
+        
         sleep(1);
+
+        update_packet(packet, payload_size);
     }
+    free(packet);
+    free(buffer);
 }