1 files changed, 86 insertions, 0 deletions

diff --git a/analysis/rtt/src/logger.c b/analysis/rtt/src/logger.c
new file mode 100644
index 0000000..ed5f6e5
--- /dev/null
+++ b/analysis/rtt/src/logger.c
@@ -0,0 +1,86 @@
+
+#include "logger.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+
+#define WINDOW_SEC 1
+#define MAX_TIMES 1000
+
+static FILE *csv_file = NULL;
+static double msg_times[MAX_TIMES];
+static int msg_count = 0;
+
+static long long current_time_ms() {
+  struct timeval tv;
+  gettimeofday(&tv, NULL);
+  return ((long long)tv.tv_sec * 1000) + (tv.tv_usec / 1000);
+}
+
+static double current_time_sec() {
+  struct timeval tv;
+  gettimeofday(&tv, NULL);
+  return (double)tv.tv_sec + (tv.tv_usec / 1e6);
+}
+
+static int update_throughput_window(double now) {
+  int i, new_count = 0;
+  for (i = 0; i < msg_count; i++) {
+    if (now - msg_times[i] < WINDOW_SEC) {
+      msg_times[new_count++] = msg_times[i];
+    }
+  }
+  msg_times[new_count++] = now;
+  msg_count = new_count;
+  return msg_count;
+}
+
+void logger_init(const char *filename) {
+  csv_file = fopen(filename, "w");
+  if (!csv_file) {
+    perror("Cannot open CSV file");
+    exit(EXIT_FAILURE);
+  }
+  fprintf(csv_file,
+          "timestamp,sent_ms,received_ms,rtt_ms,throughput_msg_per_s\n");
+  fflush(csv_file);
+}
+
+void logger_cleanup() {
+  if (csv_file) {
+    fclose(csv_file);
+    csv_file = NULL;
+  }
+}
+
+void logger_handle_message(const void *payload, int payloadlen) {
+  char *payload_str = malloc(payloadlen + 1);
+  if (!payload_str)
+    return;
+  memcpy(payload_str, payload, payloadlen);
+  payload_str[payloadlen] = '\0';
+
+  long long sent_ms = atoll(payload_str);
+  free(payload_str);
+
+  long long received_ms = current_time_ms();
+  long long rtt = received_ms - sent_ms;
+
+  double now_sec = current_time_sec();
+  int throughput = update_throughput_window(now_sec);
+
+  time_t now = time(NULL);
+  struct tm *tm_info = localtime(&now);
+  char iso_time[32];
+  strftime(iso_time, sizeof(iso_time), "%Y-%m-%dT%H:%M:%S", tm_info);
+
+  if (csv_file) {
+    fprintf(csv_file, "%s,%lld,%lld,%lld,%d\n", iso_time, sent_ms, received_ms,
+            rtt, throughput);
+    fflush(csv_file);
+  }
+
+  printf("RTT: %lld ms | Throughput: %d msg/s\n", rtt, throughput);
+}