From 49c7d0178984ddac9cb8c935b65729448e87679c Mon Sep 17 00:00:00 2001
From: Kamil Trzcinski <ayufan@ayufan.eu>
Date: Fri, 24 Feb 2023 19:59:56 +0100
Subject: [PATCH] buffer: if last buffer is discovered restart streaming

---
 device/buffer.h           |  1 +
 device/links.c            |  7 +++++++
 device/v4l2/buffer.c      |  1 +
 device/v4l2/buffer_list.c | 18 ++++++++++++++++++
 4 files changed, 27 insertions(+)

diff --git a/device/buffer.h b/device/buffer.h
index e93e716..85418f2 100644
--- a/device/buffer.h
+++ b/device/buffer.h
@@ -20,6 +20,7 @@ typedef struct buffer_s {
 
   struct {
     bool is_keyframe : 1;
+    bool is_last : 1;
   } flags;
 
   union {
diff --git a/device/links.c b/device/links.c
index 54ee9d3..4f44ba7 100644
--- a/device/links.c
+++ b/device/links.c
@@ -151,6 +151,13 @@ static int links_enqueue_from_capture_list(buffer_list_t *capture_list, link_t *
     LOG_ERROR(capture_list, "No buffer dequeued from capture_list?");
   }
 
+  if (buf->flags.is_last) {
+    LOG_INFO(buf, "Received last buffer. Restarting streaming...");
+    buffer_list_set_stream(capture_list, false);
+    buffer_list_set_stream(capture_list, true);
+    return 0;
+  }
+
   uint64_t now_us = get_monotonic_time_us(NULL, NULL);
   if ((now_us - buf->captured_time_us) > CAPTURE_TIMEOUT_US) {
     LOG_INFO(buf, "Capture image is outdated. Skipped. Now: %" PRIu64 ", vs %" PRIu64 ".",
diff --git a/device/v4l2/buffer.c b/device/v4l2/buffer.c
index 8cbb130..e05ff03 100644
--- a/device/v4l2/buffer.c
+++ b/device/v4l2/buffer.c
@@ -151,6 +151,7 @@ int v4l2_buffer_list_dequeue(buffer_list_t *buf_list, buffer_t **bufp)
 
   buf->v4l2->flags = v4l2_buf.flags;
   buf->flags.is_keyframe = (v4l2_buf.flags & V4L2_BUF_FLAG_KEYFRAME) != 0;
+  buf->flags.is_last = (v4l2_buf.flags & V4L2_BUF_FLAG_LAST) != 0;
   buf->captured_time_us = get_time_us(CLOCK_FROM_PARAMS, NULL, &v4l2_buf.timestamp, 0);
   return 0;
 
diff --git a/device/v4l2/buffer_list.c b/device/v4l2/buffer_list.c
index 50944ce..62423a2 100644
--- a/device/v4l2/buffer_list.c
+++ b/device/v4l2/buffer_list.c
@@ -181,6 +181,24 @@ int v4l2_buffer_list_set_stream(buffer_list_t *buf_list, bool do_on)
 	enum v4l2_buf_type type = buf_list->v4l2->type;
   ERR_IOCTL(buf_list, buf_list->v4l2->dev_fd, do_on ? VIDIOC_STREAMON : VIDIOC_STREAMOFF, &type, "Cannot set streaming state");
 
+  if (!do_on) {
+    // forcefully dequeue all buffers
+    for (int i = 0; i < buf_list->nbufs; i++) {
+      buffer_t *buf = buf_list->bufs[i];
+      if (!buf->enqueued)
+        continue;
+
+      if (buf->dma_source) {
+        buf->dma_source->used = 0;
+        buffer_consumed(buf->dma_source, "stream-off");
+        buf->dma_source = NULL;
+      }
+
+      buf->enqueued = false;
+      buf->mmap_reflinks = 1;
+    }
+  }
+
   return 0;
 error:
   return -1;