[FFmpeg-cvslog] apedec: do not set s->samples until after validation.

[Justin Ruggles]

ffmpeg | branch: master | Justin Ruggles <justin.ruggles at gmail.com> | Tue Oct 11 12:49:46 2011 -0400| [b7e514575982fd2f5db5ea4f3b466d6dd6a08aa7] | committer: Justin Ruggles

apedec: do not set s->samples until after validation.

This prevents errors and/or invalid writes in the next decode call due to
s->samples still being negative.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b7e514575982fd2f5db5ea4f3b466d6dd6a08aa7
---

 libavcodec/apedec.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c
index 2041e2b..a741c7d 100644
--- a/libavcodec/apedec.c
+++ b/libavcodec/apedec.c
@@ -832,7 +832,7 @@ static int ape_decode_frame(AVCodecContext *avctx,
         s->ptr = s->last_ptr = s->data;
         s->data_end = s->data + buf_size;
 
-        nblocks = s->samples = bytestream_get_be32(&s->ptr);
+        nblocks = bytestream_get_be32(&s->ptr);
         n =  bytestream_get_be32(&s->ptr);
         if(n < 0 || n > 3){
             av_log(avctx, AV_LOG_ERROR, "Incorrect offset passed\n");
@@ -843,10 +843,11 @@ static int ape_decode_frame(AVCodecContext *avctx,
 
         s->currentframeblocks = nblocks;
         buf += 4;
-        if (s->samples <= 0) {
+        if (nblocks <= 0) {
             *data_size = 0;
             return buf_size;
         }
+        s->samples = nblocks;
 
         memset(s->decoded0,  0, sizeof(s->decoded0));
         memset(s->decoded1,  0, sizeof(s->decoded1));