libuvc: add cancel fd to quit poll thread

Author: gozfree

gear-lib/librpc/librpc.c

@@ -111,7 +111,7 @@ void print_session(struct rpc_session *ss)
     printf("session.msg_id      = 0x%08x\n", ss->msg_id);
     printf("session.timestamp   = %" PRIu64 "(%s)\n", ss->timestamp,
             time_str_format_by_msec(ss->timestamp, ts, sizeof(ts)));
-    printf("session.checksum    = 0x%08lx\n", ss->cseq);
+    printf("session.checksum    = 0x%" PRIx64 "\n", ss->cseq);
     printf("================\n");
 }
 

gear-lib/libuvc/test_libuvc.c

@@ -38,7 +38,11 @@ static struct file *fp;
 
 static int on_frame(struct uvc_ctx *c, struct video_frame *frm)
 {
-    printf("frm[%" PRIu64 "] size=%" PRIu64 ", ts=%" PRIu64 " ms\n", frm->frame_id, frm->total_size, frm->timestamp/1000000);
+    static uint64_t last_ms = 0;
+
+    printf("frm[%" PRIu64 "] size=%" PRIu64 ", ts=%" PRIu64 " ms, gap=%" PRIu64 " ms\n",
+          frm->frame_id, frm->total_size, frm->timestamp/1000000, frm->timestamp/1000000 - last_ms);
+    last_ms = frm->timestamp/1000000;
     file_write(fp, frm->data[0], frm->total_size);
     return 0;
 }
@@ -82,7 +86,7 @@ int dummy_test()
     struct uvc_config conf = {
         .width  = 320,
         .height = 240,
-        .fps    = {5, 1},
+        .fps    = {30, 1},
         .format = PIXEL_FORMAT_YUY2,
     };
     struct uvc_ctx *uvc = uvc_open(UVC_TYPE_DUMMY, "sample_yuv422p.yuv", &conf);

gear-lib/libuvc/v4l2.c

@@ -32,6 +32,7 @@
 #include <sys/uio.h>
 #include <sys/mman.h>
 #include <sys/epoll.h>
+#include <sys/eventfd.h>
 #include <linux/videodev2.h>
 
 /*
@@ -78,6 +79,7 @@ static const uint32_t v4l2_cid_supported[] = {
 
 struct v4l2_ctx {
     int fd;
+    int cancel_fd;
     int channel; /*one video node may contain several input channel */
     int standard;
     uint32_t pixfmt;
@@ -206,6 +208,7 @@ static void *uvc_v4l2_open(struct uvc_ctx *uvc, const char *dev, struct uvc_conf
         goto failed;
     }
     c->fd = fd;
+    c->cancel_fd = eventfd(0, 0);
 
     c->channel = -1;
     c->standard = -1;
@@ -501,6 +504,10 @@ static int uvc_v4l2_poll_init(struct v4l2_ctx *c)
         printf("epoll_ctl EPOLL_CTL_ADD failed %d!\n", errno);
         return -1;
     }
+    if (-1 == epoll_ctl(c->epfd, EPOLL_CTL_ADD, c->cancel_fd, &epev)) {
+        printf("epoll_ctl EPOLL_CTL_ADD failed %d!\n", errno);
+        return -1;
+    }
     return 0;
 }
 
@@ -603,6 +610,7 @@ static int uvc_v4l2_start_stream(struct uvc_ctx *uvc)
 static int uvc_v4l2_stop_stream(struct uvc_ctx *uvc)
 {
     int i;
+    uint64_t notify = '1';
     enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
     struct v4l2_ctx *c = (struct v4l2_ctx *)uvc->opaque;
 
@@ -613,6 +621,9 @@ static int uvc_v4l2_stop_stream(struct uvc_ctx *uvc)
 
     if (uvc->on_video_frame) {
         c->is_streaming = false;
+        if (sizeof(uint64_t) != write(c->cancel_fd, &notify, sizeof(uint64_t))) {
+            perror("write error");
+        }
         thread_join(c->thread);
         thread_destroy(c->thread);
     }