Discard stale playback snapshots before reseeking a media cursor

tools/chatgui-android/libutun_lite/stream_bridge.c

@@ -244,14 +244,14 @@ static void media_process(void *arg) {
         }
     }
     if (viewer.stopping && viewer.id) media_close(&viewer, 5);
-    if (viewer.handle) {
-        int result = stream_media_get_status(viewer.handle, &viewer_status);
-        if (result < 0) { DEBUG_ERROR(DEBUG_CATEGORY_STREAM, "Android media index failed result=%d", result); media_close(&viewer, 6); }
-    }
     if (viewer.handle && (viewer.resync || viewer.rx_overflow)) {
         viewer.resync = viewer.rx_overflow = 0; viewer.position = -1; viewer.waiting = 0;
         if (stream_media_resync(viewer.handle) != STREAM_OK) media_close(&viewer, 6);
     }
+    if (viewer.handle) {
+        int result = stream_media_get_status(viewer.handle, &viewer_status);
+        if (result < 0) { DEBUG_ERROR(DEBUG_CATEGORY_STREAM, "Android media index failed result=%d", result); media_close(&viewer, 6); }
+    }
     unsigned queued_viewer = 0;
     for (struct media_record *r = output_queue.head; r; r = r->next) if (r->id == viewer.id) queued_viewer++;
     if (viewer.handle && viewer.want_read && queued_viewer < 2
@@ -271,6 +271,7 @@ static void media_process(void *arg) {
         else if (result == STREAM_GAP || result == STREAM_EXPIRED) {
             DEBUG_INFO(DEBUG_CATEGORY_STREAM, "Android playback resync id=%llu result=%d", (unsigned long long)viewer.id, result);
             stream_media_resync(viewer.handle); viewer.position = -1; media_output(viewer.id, 3, NULL, 0, 0, NULL, 0);
+            memset(&viewer_status, 0, sizeof(viewer_status));
         } else { DEBUG_ERROR(DEBUG_CATEGORY_STREAM, "Android playback read failed result=%d", result); media_close(&viewer, 6); }
     }
     if (publisher.handle && !stream_handle_active(publisher.handle)) media_close(&publisher, 6);
@@ -495,6 +496,7 @@ int android_stream_resync(uint64_t id) {
     int result = -1;
     if (viewer.id == id && viewer.handle) {
         media_drop_output(); viewer.resync = viewer.want_read = 1; viewer.waiting = 0; viewer.position = -1;
+        memset(&viewer_status, 0, sizeof(viewer_status));
         result = media_schedule();
     }
     pthread_mutex_unlock(&media_lock); return result;

tools/chatgui/transport/stream_bridge.cpp

@@ -135,15 +135,15 @@ void process(void*) {
     bridge.wantRead = true;
     }
     if (!bridge.handle) return;
+    if (bridge.resync) {
+        bridge.resync = false; bridge.position = -1;
+        if (stream_media_resync(bridge.handle) != STREAM_OK) { closeViewer(StreamRecordKind::Closed, STREAM_CLOSE_FAILED); return; }
+    }
     int statusResult = stream_media_get_status(bridge.handle, &bridge.status);
     if (statusResult < 0) {
         DEBUG_ERROR(DEBUG_CATEGORY_STREAM, "desktop media index failed result=%d", statusResult);
         closeViewer(StreamRecordKind::Closed, STREAM_CLOSE_FAILED); return;
     }
-    if (bridge.resync) {
-        bridge.resync = false; bridge.position = -1;
-        if (stream_media_resync(bridge.handle) != STREAM_OK) { closeViewer(StreamRecordKind::Closed, STREAM_CLOSE_FAILED); return; }
-    }
     if (!bridge.wantRead || bridge.output.size() >= 2 || bridge.bytes + STREAM_MEDIA_MAX_FRAME > 4u * 1024u * 1024u) return;
     bridge.wantRead = false;
     stream_media_packet packet{};
@@ -158,6 +158,7 @@ void process(void*) {
     else if (result == STREAM_GAP || result == STREAM_EXPIRED) {
         DEBUG_INFO(DEBUG_CATEGORY_STREAM, "desktop playback resync id=%llu result=%d", (unsigned long long)bridge.viewer.id, result);
         stream_media_resync(bridge.handle); bridge.position = -1;
+        bridge.status = {};
         output({bridge.viewer.id, 0, StreamRecordKind::Gap});
     } else {
         DEBUG_ERROR(DEBUG_CATEGORY_STREAM, "desktop playback read failed result=%d", result);
@@ -245,6 +246,7 @@ bool gui_stream_resync(uint64_t id) {
     std::lock_guard<std::mutex> guard(bridge.lock);
     if (bridge.viewer.id != id || !bridge.handle) return false;
     bridge.resync = bridge.wantRead = true; bridge.waiting = false; bridge.position = -1;
+    bridge.status = {};
     bridge.output.clear(); bridge.bytes = 0;
     return schedule();
 }