musepack: fix signed shift overflow in mpc_read_packet()

Using an unsigned variable avoids problems with overflows.
There is further no need for a 64-bit intermediate here.

Signed-off-by: Mans Rullgard <mans@mansr.com>
This commit is contained in:
Mans Rullgard 2011-11-27 10:29:33 +00:00
parent 028a2375e2
commit d9ba767d61

View File

@ -117,7 +117,8 @@ static int mpc_read_packet(AVFormatContext *s, AVPacket *pkt)
{
MPCContext *c = s->priv_data;
int ret, size, size2, curbits, cur = c->curframe;
int64_t tmp, pos;
unsigned tmp;
int64_t pos;
if (c->curframe >= c->fcount && c->fcount)
return -1;
@ -134,8 +135,7 @@ static int mpc_read_packet(AVFormatContext *s, AVPacket *pkt)
if(curbits <= 12){
size2 = (tmp >> (12 - curbits)) & 0xFFFFF;
}else{
tmp = (tmp << 32) | avio_rl32(s->pb);
size2 = (tmp >> (44 - curbits)) & 0xFFFFF;
size2 = (tmp << (curbits - 12) | avio_rl32(s->pb) >> (44 - curbits)) & 0xFFFFF;
}
curbits += 20;
avio_seek(s->pb, pos, SEEK_SET);