add: preload

src/main.c

@@ -77,6 +77,7 @@ static int get_setting(char * const *av, struct setting *setting)
         {NULL, "n", OPTION, false},
         {"ttl", NULL, ARGUMENT, "116"},
         {NULL, "s", ARGUMENT, "56"},
+        {NULL, "p", ARGUMENT, "0"},
         {NULL, NULL, 0, NULL},
     };
     char *hostname = parsing(av, parameters);
@@ -90,9 +91,11 @@ static int get_setting(char * const *av, struct setting *setting)
     size_t ttl;
     if (parsing_number(parameters[3].value, 0, 255, &ttl))
         return 2;
+    setting->ttl = ttl;
     if (parsing_number(parameters[4].value, 0, 2147483647, &setting->payload_size))
         return 3;
-    setting->ttl = ttl;
+    if (parsing_number(parameters[5].value, 0, 2147483647, &setting->preload))
+        return 4;
     return  0;
 }
 
@@ -180,6 +183,17 @@ int main(int ac, char **av)
     bzero(&stats, sizeof(struct statistics));
     print_header(&settings);
 
+    for (size_t i = 0; i < settings.payload_size; i++)
+    {
+        if (sendto(sockfd, packet, packet_size, 0,  (struct sockaddr *) &settings.dest.ip, sizeof(settings.dest.ip)) == -1)
+        {
+            print_err("error: send packet failed.");
+            free(packet);
+            close(sockfd);
+            return 2;
+        }
+    }
+
     while (loop) {
 
         struct timeval stop, start;
@@ -198,7 +212,6 @@ int main(int ac, char **av)
         int ret = 0;
         do
         {
-            buffer[0] = 0;
             ret = recvfrom(sockfd, buffer, packet_size, 0, (struct sockaddr *) &sender, &len) < 0;
             if (ret == -1)
             {

src/setting.h

@@ -16,4 +16,5 @@ struct setting
     uint8_t ttl;
     size_t payload_size;
     struct hostenv dest;
+    size_t preload;
 };