From e5c7aca046394f605c0749c78a7b0e24499324c9 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?J=C3=B6rn=20Heusipp?= <osmanx@problemloesungsmaschine.de>

Date: Tue, 20 Mar 2018 17:55:10 +0300

Subject: [PATCH] Fix reading maximum, nominal, minimum bitrate in _vorbis_unpack_info().

(vorbis.git commit 68ebc894325f56ae1d860d49626419cf66ea171b)

https://xiph.org/vorbis/doc/Vorbis_I_spec.html#x1-630004.2.2 specifies

these fields as 32bit signed. oggpack_read(opb,32), which is used to

read these fields, returns 32 bits stored in a long. On architectures

where long is 64bit, this results in a positive value being returned.

This value is then stored in struct vorbis_info in bitrate_upper,

bitrate_nominal and bitrate_lower, also as long. ogginfo relies on

these values in order to display the respective header fields and thus

misrepresented the stored value -1 (which has the intended meaning of

"bitrate not set") as 2**32-1 on architectures where long is 64bit.

Explicitly cast the return value of oggpack_read() to a signed 32bit

integer type.

A nominal bitrate value of -1 is valid as per specification, and is

written by libvorbis for VBR files with samplerate >= 50000Hz.

Signed-off-by: Timothy B. Terriberry <tterribe@xiph.org>

---

info.c | 6 +++---

1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/info.c b/info.c

index 71e879a..11cfbb6 100644

--- a/info.c

+++ b/info.c

@@ -166,9 +166,9 @@ static int _vorbis_unpack_info(vorbis_info *vi,oggpack_buffer *opb){

vi->channels=oggpack_read(opb,8);

vi->rate=oggpack_read(opb,32);

- vi->bitrate_upper=oggpack_read(opb,32);

- vi->bitrate_nominal=oggpack_read(opb,32);

- vi->bitrate_lower=oggpack_read(opb,32);

+ vi->bitrate_upper=(ogg_int32_t)oggpack_read(opb,32);

+ vi->bitrate_nominal=(ogg_int32_t)oggpack_read(opb,32);

+ vi->bitrate_lower=(ogg_int32_t)oggpack_read(opb,32);

ci->blocksizes[0]=1<<oggpack_read(opb,4);

ci->blocksizes[1]=1<<oggpack_read(opb,4);

--

1.7.1