[vlc-commits] contrib: ffmpeg: Backport an upstreamed patch

[Hugo Beauzée-Luyssen]

vlc/vlc-3.0 | branch: master | Hugo Beauzée-Luyssen <hugo at beauzee.fr> | Wed Feb 20 15:52:29 2019 +0100| [a3c1b05a7a3b64697b9c21ac936d05cc61e30517] | committer: Hugo Beauzée-Luyssen

contrib: ffmpeg: Backport an upstreamed patch

> http://git.videolan.org/gitweb.cgi/vlc/vlc-3.0.git/?a=commit;h=a3c1b05a7a3b64697b9c21ac936d05cc61e30517
---

 ...memset-size-on-ctts_data-in-mov_read_trun.patch | 68 ++++++++++++++++++++++
 contrib/src/ffmpeg/rules.mak                       |  1 +
 2 files changed, 69 insertions(+)

diff --git a/contrib/src/ffmpeg/0006-ffmpeg-Fix-memset-size-on-ctts_data-in-mov_read_trun.patch b/contrib/src/ffmpeg/0006-ffmpeg-Fix-memset-size-on-ctts_data-in-mov_read_trun.patch
new file mode 100644
index 0000000000..caad5954c2
--- /dev/null
+++ b/contrib/src/ffmpeg/0006-ffmpeg-Fix-memset-size-on-ctts_data-in-mov_read_trun.patch
@@ -0,0 +1,68 @@
+From f5f2209d689cd17f4bce7ce5c4f0b1634befc785 Mon Sep 17 00:00:00 2001
+From: Xiaohan Wang <xhwang at chromium.org>
+Date: Fri, 23 Feb 2018 17:04:41 -0800
+Subject: [PATCH] ffmpeg: Fix memset size on ctts_data in mov_read_trun()
+ (round 2)
+
+The allocated size of sc->ctts_data is
+(st->nb_index_entries + entries) * sizeof(*sc->ctts_data).
+
+The size to memset at offset sc->ctts_data + sc->ctts_count should be
+(st->nb_index_entries + entries - sc->ctts_count) *
+sizeof(*sc->ctts_data))
+
+The current code missed |entries| I believe, which was introduced in
+https://patchwork.ffmpeg.org/patch/5541/.
+
+However, after offline discussion, it seems the original code is much
+more clear to read (before https://patchwork.ffmpeg.org/patch/5541/).
+
+Hence this CL revert the memset logic to it's previous state by
+remembering the |old_ctts_allocated_size|, and only memset the newly
+allocated entries.
+
+BUG=812567
+
+Change-Id: Ibe94c7138e5818bfaae76866bfa6619a9b8a2b6b
+Reviewed-on: https://chromium-review.googlesource.com/934925
+Reviewed-by: Dale Curtis <dalecurtis at chromium.org>
+
+Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
+---
+ libavformat/mov.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+diff --git a/libavformat/mov.c b/libavformat/mov.c
+index 04567fc475..f01116874c 100644
+--- a/libavformat/mov.c
++++ b/libavformat/mov.c
+@@ -4596,6 +4596,7 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+     int64_t prev_dts = AV_NOPTS_VALUE;
+     int next_frag_index = -1, index_entry_pos;
+     size_t requested_size;
++    size_t old_ctts_allocated_size;
+     AVIndexEntry *new_entries;
+     MOVFragmentStreamInfo * frag_stream_info;
+ 
+@@ -4688,6 +4689,7 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+     st->index_entries= new_entries;
+ 
+     requested_size = (st->nb_index_entries + entries) * sizeof(*sc->ctts_data);
++    old_ctts_allocated_size = sc->ctts_allocated_size;
+     ctts_data = av_fast_realloc(sc->ctts_data, &sc->ctts_allocated_size,
+                                 requested_size);
+     if (!ctts_data)
+@@ -4697,8 +4699,8 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+     // In case there were samples without ctts entries, ensure they get
+     // zero valued entries. This ensures clips which mix boxes with and
+     // without ctts entries don't pickup uninitialized data.
+-    memset(sc->ctts_data + sc->ctts_count, 0,
+-           (st->nb_index_entries - sc->ctts_count) * sizeof(*sc->ctts_data));
++    memset((uint8_t*)(sc->ctts_data) + old_ctts_allocated_size, 0,
++           sc->ctts_allocated_size - old_ctts_allocated_size);
+ 
+     if (index_entry_pos < st->nb_index_entries) {
+         // Make hole in index_entries and ctts_data for new samples
+-- 
+2.20.1
+
diff --git a/contrib/src/ffmpeg/rules.mak b/contrib/src/ffmpeg/rules.mak
index 74ea2a5be6..ed5ea79b55 100644
--- a/contrib/src/ffmpeg/rules.mak
+++ b/contrib/src/ffmpeg/rules.mak
@@ -237,6 +237,7 @@ ifdef USE_FFMPEG
 	$(APPLY) $(SRC)/ffmpeg/0003-arm-swscale-Only-compile-the-rgb2yuv-asm-if-.dn-alia.patch
 	$(APPLY) $(SRC)/ffmpeg/0004-arm-hevcdsp-Avoid-using-macro-expansion-counters.patch
 	$(APPLY) $(SRC)/ffmpeg/0005-arm-hevcdsp-Add-commas-between-macro-arguments.patch
+	$(APPLY) $(SRC)/ffmpeg/0006-ffmpeg-Fix-memset-size-on-ctts_data-in-mov_read_trun.patch
 	$(APPLY) $(SRC)/ffmpeg/armv7_fixup.patch
 	$(APPLY) $(SRC)/ffmpeg/dxva_vc1_crash.patch
 	$(APPLY) $(SRC)/ffmpeg/h264_early_SAR.patch