pleroma

commit: 50edef5bc13d0407aaaf26c951ce7a4a8cd4db58
parent 8ac4458630026387a5394b427daa409b0d2667ba
Author: Mark Felder <feld@feld.me>
Date:   Fri, 29 Dec 2023 14:12:44 -0500

Change QTFastStart to recover gracefully if it encounters an error during bitstring matching

This fixes issues with internal errors when trying to serve the video

Diffstat:
A
changelog.d/qtfaststart.fix
1
+
M
lib/pleroma/helpers/qt_fast_start.ex
25
+++++++++++++++----------

2 files changed, 16 insertions(+), 10 deletions(-)
diff --git a/changelog.d/qtfaststart.fix b/changelog.d/qtfaststart.fix
@@ -0,0 +1 @@
+MediaProxy Preview failures prevented when encountering certain video files
diff --git a/lib/pleroma/helpers/qt_fast_start.ex b/lib/pleroma/helpers/qt_fast_start.ex
@@ -40,16 +40,21 @@ defmodule Pleroma.Helpers.QtFastStart do
          got_mdat,
          acc
        ) do
-    full_size = (size - 8) * 8
-    <<data::bits-size(full_size), rest::bits>> = rest
-
-    acc = [
-      {fourcc, pos, pos + size, size,
-       <<size::integer-big-size(32), fourcc::bits-size(32), data::bits>>}
-      | acc
-    ]
-
-    fix(rest, pos + size, got_moov || fourcc == "moov", got_mdat || fourcc == "mdat", acc)
+    try do
+      full_size = (size - 8) * 8
+      <<data::bits-size(full_size), rest::bits>> = rest
+
+      acc = [
+        {fourcc, pos, pos + size, size,
+         <<size::integer-big-size(32), fourcc::bits-size(32), data::bits>>}
+        | acc
+      ]
+
+      fix(rest, pos + size, got_moov || fourcc == "moov", got_mdat || fourcc == "mdat", acc)
+    rescue
+      _ ->
+        :abort
+    end
   end
 
   defp fix(<<>>, _pos, _, _, acc) do