From af228706f14696e818f4004691d4de0006ac4910 Mon Sep 17 00:00:00 2001
From: Romain Vimont <rom@rom1v.com>
Date: Sun, 13 Jun 2021 18:31:48 +0200
Subject: [PATCH] Fix compatibility with old FFmpeg

V4L2 sink used a "url" field format AVFormatContext which has been
introduced in lavf 58.7.100.

Fixes #2382 <https://github.com/Genymobile/scrcpy/issues/2382>

Refs <https://github.com/FFmpeg/FFmpeg/commit/ea3672b7d67c432724bdbc8de0221f869b6a04c6>
Refs <https://github.com/FFmpeg/FFmpeg/commit/fa8308d3d4f27d6fb38ac2069887a7b259f1c6ab>
---
 app/src/compat.h    | 12 ++++++++++++
 app/src/v4l2_sink.c |  5 +++++
 2 files changed, 17 insertions(+)

diff --git a/app/src/compat.h b/app/src/compat.h
index 9d9a7884..8e2d18f4 100644
--- a/app/src/compat.h
+++ b/app/src/compat.h
@@ -22,6 +22,18 @@
 # define SCRCPY_LAVF_REQUIRES_REGISTER_ALL
 #endif
 
+
+// In ffmpeg/doc/APIchanges:
+// 2018-01-28 - ea3672b7d6 - lavf 58.7.100 - avformat.h
+//   Deprecate AVFormatContext filename field which had limited length, use the
+//   new dynamically allocated url field instead.
+//
+// 2018-01-28 - ea3672b7d6 - lavf 58.7.100 - avformat.h
+//   Add url field to AVFormatContext and add ff_format_set_url helper function.
+#if LIBAVFORMAT_VERSION_INT >= AV_VERSION_INT(58, 7, 100)
+# define SCRCPY_LAVF_HAS_AVFORMATCONTEXT_URL
+#endif
+
 #if SDL_VERSION_ATLEAST(2, 0, 5)
 // <https://wiki.libsdl.org/SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH>
 # define SCRCPY_SDL_HAS_HINT_MOUSE_FOCUS_CLICKTHROUGH
diff --git a/app/src/v4l2_sink.c b/app/src/v4l2_sink.c
index fd0bda12..d7c1a667 100644
--- a/app/src/v4l2_sink.c
+++ b/app/src/v4l2_sink.c
@@ -180,12 +180,17 @@ sc_v4l2_sink_open(struct sc_v4l2_sink *vs) {
     // still expects a pointer-to-non-const (it has not be updated accordingly)
     // <https://github.com/FFmpeg/FFmpeg/commit/0694d8702421e7aff1340038559c438b61bb30dd>
     vs->format_ctx->oformat = (AVOutputFormat *) format;
+#ifdef SCRCPY_LAVF_HAS_AVFORMATCONTEXT_URL
     vs->format_ctx->url = strdup(vs->device_name);
     if (!vs->format_ctx->url) {
         LOGE("Could not strdup v4l2 device name");
         goto error_avformat_free_context;
         return false;
     }
+#else
+    strncpy(vs->format_ctx->filename, vs->device_name,
+            sizeof(vs->format_ctx->filename));
+#endif
 
     AVStream *ostream = avformat_new_stream(vs->format_ctx, encoder);
     if (!ostream) {