From 0d7674052bd8769dcb9c18aff3cc827b3e080cf7 Mon Sep 17 00:00:00 2001
From: Bob <bob@umbernetworks.com>
Date: Sun, 14 Dec 2025 14:48:56 -0800
Subject: [PATCH] more on control_iperf.py support

---
 components/iperf/iperf.c | 37 +++++++++++++++++++++++++++++++------
 1 file changed, 31 insertions(+), 6 deletions(-)

diff --git a/components/iperf/iperf.c b/components/iperf/iperf.c
index 2375808..31abc82 100644
--- a/components/iperf/iperf.c
+++ b/components/iperf/iperf.c
@@ -64,7 +64,6 @@ void iperf_print_status(void) {
         err = (float)diff * 100.0f / (float)s_stats.config_pps;
     }
 
-    // Format expected by Python regex
     printf("IPERF_STATUS: Running=%d, Config=%" PRIu32 ", Actual=%" PRIu32 ", Err=%.1f%%\n",
            s_stats.running, s_stats.config_pps, s_stats.actual_pps, err);
 }
@@ -198,12 +197,19 @@ static esp_err_t iperf_start_udp_client(iperf_ctrl_t *ctrl) {
 
         for (int k = 0; k < ctrl->cfg.burst_count; k++) {
             udp_datagram *hdr = (udp_datagram *)ctrl->buffer;
+
+            // 1. Sequence ID
             hdr->id = htonl(packet_id++);
+
+            // 2. Timestamp
             struct timeval tv;
             gettimeofday(&tv, NULL);
             hdr->tv_sec = htonl(tv.tv_sec);
             hdr->tv_usec = htonl(tv.tv_usec);
 
+            // 3. ID2 (Required for some iperf parsers)
+            hdr->id2 = hdr->id;
+
             if (sendto(sockfd, ctrl->buffer, ctrl->cfg.send_len, 0, (struct sockaddr *)&addr, sizeof(addr)) > 0) {
                 packets_since_check++;
             } else {
@@ -221,12 +227,10 @@ static esp_err_t iperf_start_udp_client(iperf_ctrl_t *ctrl) {
         if (now - last_rate_check > RATE_CHECK_INTERVAL_US) {
             uint32_t interval_us = (uint32_t)(now - last_rate_check);
 
-            // Calculate actual PPS
             if (interval_us > 0) {
                 s_stats.actual_pps = (uint32_t)((uint64_t)packets_since_check * 1000000 / interval_us);
             }
 
-            // LED Feedback
             uint32_t config_pps = iperf_get_pps();
             uint32_t threshold = (config_pps * 3) / 4;
             led_state_t target = (s_stats.actual_pps >= threshold) ? LED_STATE_TRANSMITTING : LED_STATE_TRANSMITTING_SLOW;
@@ -240,11 +244,34 @@ static esp_err_t iperf_start_udp_client(iperf_ctrl_t *ctrl) {
     }
 
 exit:
+    // --- SEND TERMINATION PACKETS ---
+    // Send a negative sequence ID to tell the server the session is done.
+    // This allows immediate restart without waiting for server timeout.
+    {
+        udp_datagram *hdr = (udp_datagram *)ctrl->buffer;
+        int32_t final_id = -(packet_id); // Negative ID signals End of Stream
+
+        hdr->id = htonl(final_id);
+        hdr->id2 = hdr->id;
+
+        struct timeval tv;
+        gettimeofday(&tv, NULL);
+        hdr->tv_sec = htonl(tv.tv_sec);
+        hdr->tv_usec = htonl(tv.tv_usec);
+
+        // Send a burst of death packets to ensure delivery over UDP
+        for(int i=0; i<10; i++) {
+            sendto(sockfd, ctrl->buffer, ctrl->cfg.send_len, 0, (struct sockaddr *)&addr, sizeof(addr));
+            vTaskDelay(pdMS_TO_TICKS(2));
+        }
+        ESP_LOGI(TAG, "Sent termination packets (ID: %ld)", (long)final_id);
+    }
+
     close(sockfd);
+
     // Cleanup State
     s_stats.running = false;
     s_stats.actual_pps = 0;
-    // Reset LED to Green (Connected)
     status_led_set_state(LED_STATE_CONNECTED);
     printf("IPERF_STOPPED\n");
     return ESP_OK;
@@ -258,7 +285,6 @@ static void iperf_task(void *arg) {
     }
 
     free(ctrl->buffer);
-    // CRITICAL: Clear handle so start() can run again
     s_iperf_task_handle = NULL;
     vTaskDelete(NULL);
 }
@@ -289,7 +315,6 @@ void iperf_stop(void) {
         s_iperf_ctrl.finish = true;
         if (s_iperf_event_group) xEventGroupSetBits(s_iperf_event_group, IPERF_STOP_REQ_BIT);
     } else {
-        // If already stopped, just print to satisfy controller
         printf("IPERF_STOPPED\n");
     }
 }