int url_lpread(URLContext *s,unsigned char * buf,int size)
{
url_lpbuf_t *lp;
int len=size;
int valid_data_can_read;
unsigned char *tbuf=buf;
if(!s || !s->lpbuf)
return -1;
lp=s->lpbuf;
lp_lock(&lp->mutex);
lp_rprint(AV_LOG_INFO, "url_lpread:buffer=%x,rp=%x,wp=%x,end=%x,lp->valid_data_size=%d,pos=%lld\n",
lp->buffer,lp->rp,lp->wp,lp->buffer_end,lp->valid_data_size,lp->pos);
while(len>0)
{
if(lp->wp>=lp->rp)
valid_data_can_read=lp->wp-lp->rp;
else
valid_data_can_read=lp->buffer_end-lp->rp;
valid_data_can_read=FFMIN(len,valid_data_can_read);
LP_ASSERT(valid_data_can_read>=0);
if(valid_data_can_read==0)
{
int rlen;
lp_unlock(&lp->mutex);
if((len<lp->block_read_size) && (lp->seekflags & LESS_BUFF_DATA))
rlen=url_lpfillbuffer(s,len);
else
rlen=url_lpfillbuffer(s,lp->block_read_size);
if(rlen<=0)
{
lp_unlock(&lp->mutex);
return ((size-len)>0)?(size-len):rlen;
}
lp_lock(&lp->mutex);
}
lp_rprint( AV_LOG_INFO, "url_lpread:buffer=%x,rp=%x,wp=%x,end=%x,tbuf=%x,valid_data_can_read=%x(%d)\n",
lp->buffer,lp->rp,lp->wp,lp->buffer_end,tbuf,valid_data_can_read,valid_data_can_read);
if(valid_data_can_read>0)
{
if(tbuf!=NULL)
{
memcpy(tbuf,lp->rp,valid_data_can_read);
tbuf+=valid_data_can_read;
}
lp->rp+=valid_data_can_read;
if(lp->rp>=lp->buffer_end)
lp->rp=lp->buffer;
len-=valid_data_can_read;
}
LP_ASSERT(lp->rp>=lp->buffer);
LP_ASSERT(lp->rp<lp->buffer_end);
}
lp_unlock(&lp->mutex);
return (size-len);
}
int url_lp_intelligent_buffering(URLContext *s,int size)
{
int forward_data,back_data;
int datalen;
url_lpbuf_t *lp;
int ret=-1;
if(!s || !s->lpbuf)
return AVERROR(EINVAL);
lp=s->lpbuf;
lp->dbg_cnt++;
if(size <=0)
size=lp->block_read_size;
datalen= url_lp_getbuffering_size(s,&forward_data,&back_data);
if(lp->dbg_cnt%100==0)
lp_print( AV_LOG_INFO, "url_lp buffering:datalen=%d,forward_datad=%d,back_data=%d,lp->buffer_size=%d,size=%d\n",
datalen,forward_data,back_data,lp->buffer_size,size);
if(datalen>=0 && ((forward_data/lp->buffer_size)<lp->max_forword_level) &&
((datalen <lp->buffer_size-1024) || (back_data>(forward_data/2+1)) || (back_data>3*1024*1024)) )
ret=url_lpfillbuffer(s,size);/*lest 1/3 back data && < 3M back data*/
return ret;
}
