Send increasing numbers as packet data

packet-exchange/src/client.c

@@ -54,7 +54,7 @@ typedef struct network_config {
 // Static functions
 
 static void process_options(int argc, char *argv[]);
-static void do_tsn_task(struct thread_param *param, uint64_t next_txtime);
+static void do_tsn_task(struct thread_param *param, char * data, uint64_t next_txtime);
 static void print_histograms();
 static void sigint_handler(int sig_num);
 
@@ -78,6 +78,8 @@ static enum TSNTask tsn_task;
 struct timespec measures_start;
 struct timespec measures_end;
 
+char send_data[MAX_BUFFER_SIZE];
+
 static void help(char *argv[]) {
   printf("Usage: %s -f IF  [-abthgv] [-e ETF_OFFSET] [-d BUF_LEN] [-i USEC] [-l N] [-p PRIO] [-q PACKET_PRIO] [-r USEC]\n\n", argv[0]);
   printf("       -a                    Run the real time thread on CPU1\n");
@@ -138,7 +140,8 @@ static void *packet_sending_thread(void *p) {
       if (stats->nb_cycles >= param->max_cycles)
         break;
 
-    do_tsn_task(param, next_txtime);
+    sprintf(send_data, "%d", stats->nb_cycles % 1000);
+    do_tsn_task(param, send_data, next_txtime);
 
     add_ns(&next, param->interval);
 
@@ -237,7 +240,7 @@ int main(int argc, char *argv[]) {
 }
 
 // Critical TSN task
-static void do_tsn_task(struct thread_param *param, uint64_t next_txtime) {
+static void do_tsn_task(struct thread_param *param, char * data, uint64_t next_txtime) {
   struct timespec t1, t2;
   int rtt_us;
 
@@ -245,14 +248,14 @@ static void do_tsn_task(struct thread_param *param, uint64_t next_txtime) {
   if (tsn_task == SEND_PACKET_TASK) {
 
     param->stats.packet_info = send_udp_packet(
-        enable_etf, enable_timestamps, next_txtime,
+        enable_etf, enable_timestamps, data, next_txtime,
         network_config.ip_address, histograms);
 
     // Round Trip Time measurement
   } else if (tsn_task == RTT_TASK) {
 
     clock_gettime(CLOCK_MONOTONIC, &t1);
-    send_udp_packet(0, 0, next_txtime,
+    send_udp_packet(0, 0, data, next_txtime,
                     network_config.ip_address, NULL);
     recv_udp_packet(0, 0, NULL);
     clock_gettime(CLOCK_MONOTONIC, &t2);

packet-exchange/src/send_packet.c

@@ -74,12 +74,6 @@ static void init_tx_buffer(size_t _tx_buffer_len) {
 
   tx_buffer_len = _tx_buffer_len;
   tx_buffer = malloc(tx_buffer_len);
-
-  for (int i = 0; i < (((int)tx_buffer_len) - 1); i++) {
-    tx_buffer[i] = (unsigned char)i;
-  }
-
-  tx_buffer[tx_buffer_len - 1] = '\0';
 }
 
 /*
@@ -147,6 +141,7 @@ uint64_t get_txtime() {
  * Sends udp packets
  */
 packet_info_t send_udp_packet(int use_etf, int use_timestamps,
+                                         char * data,
                                          uint64_t txtime,
                                          const char *server_ip,
                                          int64_t histograms[NB_HISTOGRAMS][MAX_HIST_VAL]) {
@@ -168,6 +163,8 @@ packet_info_t send_udp_packet(int use_etf, int use_timestamps,
     packet_info.userspace_enter_ts = ts_to_uint(ts);
   }
 
+  strcpy(tx_buffer, data);
+
   memset(&sin, 0, sizeof(sin));
   sin.sin_family = AF_INET;
   sin.sin_addr.s_addr = inet_addr(server_ip);

packet-exchange/src/send_packet.h

@@ -4,6 +4,6 @@
 #include "utilities.h"
 
 void init_udp_send(int use_etf, int use_timestamps, int so_priority, char *network_if, size_t tx_buffer_len);
-packet_info_t send_udp_packet(int use_etf, int use_timestamps, uint64_t txtime, const char *server_ip, int64_t histograms[NB_HISTOGRAMS][MAX_HIST_VAL]);
+packet_info_t send_udp_packet(int use_etf, int use_timestamps, char * data, uint64_t txtime, const char *server_ip, int64_t histograms[NB_HISTOGRAMS][MAX_HIST_VAL]);
 
 #endif

packet-exchange/src/server.c

@@ -130,7 +130,7 @@ static void *packet_receiving_thread(void *p) {
     if (tsn_task == RTT_TASK) {
 
       recv_udp_packet(0, 0, NULL);
-      send_udp_packet(0, 0, 0, network_config.ip_address, NULL);
+      send_udp_packet(0, 0, "", 0, network_config.ip_address, NULL);
 
     } else if (tsn_task == RECV_PACKET_TASK) {