From: Ronald S. Bultje <rsbultje@gmail.com>
Date: Sat, 18 Feb 2012 00:27:36 +0000 (-0800)
Subject: mjpegb: don't return 0 at the end of frame decoding.
X-Git-Tag: android-x86-4.4-r1~8529^2~3127
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=74699ac8c8b562e9f8d26e21482b89585365774a;p=android-x86%2Fexternal-ffmpeg.git

mjpegb: don't return 0 at the end of frame decoding.

Return 0 indicates "please return the same data again", i.e. it causes
an infinite loop. Instead, return that we consumed the buffer if we
finished decoding succesfully, or return an error if an error occurred.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
---

diff --git a/libavcodec/mjpegbdec.c b/libavcodec/mjpegbdec.c
index c89a5bd404..10c5addca0 100644
--- a/libavcodec/mjpegbdec.c
+++ b/libavcodec/mjpegbdec.c
@@ -69,7 +69,7 @@ read_header:
     if (get_bits_long(&hgb, 32) != MKBETAG('m','j','p','g'))
     {
         av_log(avctx, AV_LOG_WARNING, "not mjpeg-b (bad fourcc)\n");
-        return 0;
+        return AVERROR_INVALIDDATA;
     }
 
     field_size = get_bits_long(&hgb, 32); /* field size */
@@ -149,7 +149,7 @@ read_header:
         picture->quality*= FF_QP2LAMBDA;
     }
 
-    return buf_ptr - buf;
+    return buf_size;
 }
 
 AVCodec ff_mjpegb_decoder = {