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Update opusfile from 0.8 to 0.9

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This commit is contained in:
Zack Middleton 2018-03-16 13:16:41 -05:00
parent 8611eb421d
commit 58a315fe3f
7 changed files with 538 additions and 369 deletions
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253
code/opusfile-0.8/src/opusfile.c
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@ -86,14 +86,15 @@ int op_test(OpusHead *_head,
This is to prevent us spending a lot of time allocating memory and looking
for Ogg pages in non-Ogg files.*/
if(memcmp(_initial_data,"OggS",4)!=0)return OP_ENOTFORMAT;
if(OP_UNLIKELY(_initial_bytes>(size_t)LONG_MAX))return OP_EFAULT;
ogg_sync_init(&oy);
data=ogg_sync_buffer(&oy,_initial_bytes);
data=ogg_sync_buffer(&oy,(long)_initial_bytes);
if(data!=NULL){
ogg_stream_state os;
ogg_page og;
int ret;
memcpy(data,_initial_data,_initial_bytes);
ogg_sync_wrote(&oy,_initial_bytes);
ogg_sync_wrote(&oy,(long)_initial_bytes);
ogg_stream_init(&os,-1);
err=OP_FALSE;
do{
@ -147,7 +148,7 @@ static int op_get_data(OggOpusFile *_of,int _nbytes){
int nbytes;
OP_ASSERT(_nbytes>0);
buffer=(unsigned char *)ogg_sync_buffer(&_of->oy,_nbytes);
nbytes=(int)(*_of->callbacks.read)(_of->source,buffer,_nbytes);
nbytes=(int)(*_of->callbacks.read)(_of->stream,buffer,_nbytes);
OP_ASSERT(nbytes<=_nbytes);
if(OP_LIKELY(nbytes>0))ogg_sync_wrote(&_of->oy,nbytes);
return nbytes;
@ -157,7 +158,7 @@ static int op_get_data(OggOpusFile *_of,int _nbytes){
static int op_seek_helper(OggOpusFile *_of,opus_int64 _offset){
if(_offset==_of->offset)return 0;
if(_of->callbacks.seek==NULL
||(*_of->callbacks.seek)(_of->source,_offset,SEEK_SET)){
||(*_of->callbacks.seek)(_of->stream,_offset,SEEK_SET)){
return OP_EREAD;
}
_of->offset=_offset;
@ -165,7 +166,7 @@ static int op_seek_helper(OggOpusFile *_of,opus_int64 _offset){
return 0;
}
/*Get the current position indicator of the underlying source.
/*Get the current position indicator of the underlying stream.
This should be the same as the value reported by tell().*/
static opus_int64 op_position(const OggOpusFile *_of){
/*The current position indicator is _not_ simply offset.
@ -369,7 +370,7 @@ static int op_get_prev_page_serial(OggOpusFile *_of,OpusSeekRecord *_sr,
search_start=llret+1;
}
/*We started from the beginning of the stream and found nothing.
This should be impossible unless the contents of the source changed out
This should be impossible unless the contents of the stream changed out
from under us after we read from it.*/
if(OP_UNLIKELY(!begin)&&OP_UNLIKELY(_offset<0))return OP_EBADLINK;
/*Bump up the chunk size.
@ -455,7 +456,7 @@ static opus_int64 op_get_last_page(OggOpusFile *_of,ogg_int64_t *_gp,
}
}
/*We started from at or before the beginning of the link and found nothing.
This should be impossible unless the contents of the source changed out
This should be impossible unless the contents of the stream changed out
from under us after we read from it.*/
if((OP_UNLIKELY(left_link)||OP_UNLIKELY(!begin))&&OP_UNLIKELY(_offset<0)){
return OP_EBADLINK;
@ -855,6 +856,7 @@ static int op_find_initial_pcm_offset(OggOpusFile *_of,
/*Fail if the pre-skip is non-zero, since it's asking us to skip more
samples than exist.*/
if(_link->head.pre_skip>0)return OP_EBADTIMESTAMP;
_link->pcm_file_offset=0;
/*Set pcm_end and end_offset so we can skip the call to
op_find_final_pcm_offset().*/
_link->pcm_start=_link->pcm_end=0;
@ -866,7 +868,8 @@ static int op_find_initial_pcm_offset(OggOpusFile *_of,
if(_link->head.pre_skip>0)return OP_EBADTIMESTAMP;
/*Set pcm_end and end_offset so we can skip the call to
op_find_final_pcm_offset().*/
_link->pcm_end=_link->pcm_start=0;
_link->pcm_file_offset=0;
_link->pcm_start=_link->pcm_end=0;
_link->end_offset=_link->data_offset;
/*Tell the caller we've got a buffered page for them.*/
return 1;
@ -951,6 +954,7 @@ static int op_find_initial_pcm_offset(OggOpusFile *_of,
/*Update the packet count after end-trimming.*/
_of->op_count=pi;
_of->cur_discard_count=_link->head.pre_skip;
_link->pcm_file_offset=0;
_of->prev_packet_gp=_link->pcm_start=pcm_start;
_of->prev_page_offset=page_offset;
return 0;
@ -1271,6 +1275,7 @@ static int op_bisect_forward_serialno(OggOpusFile *_of,
always starts with a seek.*/
ret=op_find_initial_pcm_offset(_of,links+nlinks,NULL);
if(OP_UNLIKELY(ret<0))return ret;
links[nlinks].pcm_file_offset=total_duration;
_searched=_of->offset;
/*Mark the current link count so it can be cleaned up on error.*/
_of->nlinks=++nlinks;
@ -1390,8 +1395,8 @@ static int op_open_seekable2_impl(OggOpusFile *_of){
opus_int64 data_offset;
int ret;
/*We can seek, so set out learning all about this file.*/
(*_of->callbacks.seek)(_of->source,0,SEEK_END);
_of->offset=_of->end=(*_of->callbacks.tell)(_of->source);
(*_of->callbacks.seek)(_of->stream,0,SEEK_END);
_of->offset=_of->end=(*_of->callbacks.tell)(_of->stream);
if(OP_UNLIKELY(_of->end<0))return OP_EREAD;
data_offset=_of->links[0].data_offset;
if(OP_UNLIKELY(_of->end<data_offset))return OP_EBADLINK;
@ -1436,7 +1441,7 @@ static int op_open_seekable2(OggOpusFile *_of){
prev_page_offset=_of->prev_page_offset;
start_offset=_of->offset;
memcpy(op_start,_of->op,sizeof(*op_start)*start_op_count);
OP_ASSERT((*_of->callbacks.tell)(_of->source)==op_position(_of));
OP_ASSERT((*_of->callbacks.tell)(_of->stream)==op_position(_of));
ogg_sync_init(&_of->oy);
ogg_stream_init(&_of->os,-1);
ret=op_open_seekable2_impl(_of);
@ -1454,7 +1459,7 @@ static int op_open_seekable2(OggOpusFile *_of){
_of->cur_discard_count=_of->links[0].head.pre_skip;
if(OP_UNLIKELY(ret<0))return ret;
/*And restore the position indicator.*/
ret=(*_of->callbacks.seek)(_of->source,op_position(_of),SEEK_SET);
ret=(*_of->callbacks.seek)(_of->stream,op_position(_of),SEEK_SET);
return OP_UNLIKELY(ret<0)?OP_EREAD:0;
}
@ -1493,19 +1498,20 @@ static void op_clear(OggOpusFile *_of){
_ogg_free(_of->serialnos);
ogg_stream_clear(&_of->os);
ogg_sync_clear(&_of->oy);
if(_of->callbacks.close!=NULL)(*_of->callbacks.close)(_of->source);
if(_of->callbacks.close!=NULL)(*_of->callbacks.close)(_of->stream);
}
static int op_open1(OggOpusFile *_of,
void *_source,const OpusFileCallbacks *_cb,
void *_stream,const OpusFileCallbacks *_cb,
const unsigned char *_initial_data,size_t _initial_bytes){
ogg_page og;
ogg_page *pog;
int seekable;
int ret;
memset(_of,0,sizeof(*_of));
if(OP_UNLIKELY(_initial_bytes>(size_t)LONG_MAX))return OP_EFAULT;
_of->end=-1;
_of->source=_source;
_of->stream=_stream;
*&_of->callbacks=*_cb;
/*At a minimum, we need to be able to read data.*/
if(OP_UNLIKELY(_of->callbacks.read==NULL))return OP_EREAD;
@ -1520,18 +1526,18 @@ static int op_open1(OggOpusFile *_of,
decoding entire files from RAM.*/
if(_initial_bytes>0){
char *buffer;
buffer=ogg_sync_buffer(&_of->oy,_initial_bytes);
buffer=ogg_sync_buffer(&_of->oy,(long)_initial_bytes);
memcpy(buffer,_initial_data,_initial_bytes*sizeof(*buffer));
ogg_sync_wrote(&_of->oy,_initial_bytes);
ogg_sync_wrote(&_of->oy,(long)_initial_bytes);
}
/*Can we seek?
Stevens suggests the seek test is portable.*/
seekable=_cb->seek!=NULL&&(*_cb->seek)(_source,0,SEEK_CUR)!=-1;
seekable=_cb->seek!=NULL&&(*_cb->seek)(_stream,0,SEEK_CUR)!=-1;
/*If seek is implemented, tell must also be implemented.*/
if(seekable){
opus_int64 pos;
if(OP_UNLIKELY(_of->callbacks.tell==NULL))return OP_EINVAL;
pos=(*_of->callbacks.tell)(_of->source);
pos=(*_of->callbacks.tell)(_of->stream);
/*If the current position is not equal to the initial bytes consumed,
absolute seeking will not work.*/
if(OP_UNLIKELY(pos!=(opus_int64)_initial_bytes))return OP_EINVAL;
@ -1590,14 +1596,14 @@ static int op_open2(OggOpusFile *_of){
return ret;
}
OggOpusFile *op_test_callbacks(void *_source,const OpusFileCallbacks *_cb,
OggOpusFile *op_test_callbacks(void *_stream,const OpusFileCallbacks *_cb,
const unsigned char *_initial_data,size_t _initial_bytes,int *_error){
OggOpusFile *of;
int ret;
of=(OggOpusFile *)_ogg_malloc(sizeof(*of));
ret=OP_EFAULT;
if(OP_LIKELY(of!=NULL)){
ret=op_open1(of,_source,_cb,_initial_data,_initial_bytes);
ret=op_open1(of,_stream,_cb,_initial_data,_initial_bytes);
if(OP_LIKELY(ret>=0)){
if(_error!=NULL)*_error=0;
return of;
@ -1611,10 +1617,10 @@ OggOpusFile *op_test_callbacks(void *_source,const OpusFileCallbacks *_cb,
return NULL;
}
OggOpusFile *op_open_callbacks(void *_source,const OpusFileCallbacks *_cb,
OggOpusFile *op_open_callbacks(void *_stream,const OpusFileCallbacks *_cb,
const unsigned char *_initial_data,size_t _initial_bytes,int *_error){
OggOpusFile *of;
of=op_test_callbacks(_source,_cb,_initial_data,_initial_bytes,_error);
of=op_test_callbacks(_stream,_cb,_initial_data,_initial_bytes,_error);
if(OP_LIKELY(of!=NULL)){
int ret;
ret=op_open2(of);
@ -1627,15 +1633,15 @@ OggOpusFile *op_open_callbacks(void *_source,const OpusFileCallbacks *_cb,
/*Convenience routine to clean up from failure for the open functions that
create their own streams.*/
static OggOpusFile *op_open_close_on_failure(void *_source,
static OggOpusFile *op_open_close_on_failure(void *_stream,
const OpusFileCallbacks *_cb,int *_error){
OggOpusFile *of;
if(OP_UNLIKELY(_source==NULL)){
if(OP_UNLIKELY(_stream==NULL)){
if(_error!=NULL)*_error=OP_EFAULT;
return NULL;
}
of=op_open_callbacks(_source,_cb,NULL,0,_error);
if(OP_UNLIKELY(of==NULL))(*_cb->close)(_source);
of=op_open_callbacks(_stream,_cb,NULL,0,_error);
if(OP_UNLIKELY(of==NULL))(*_cb->close)(_stream);
return of;
}
@ -1653,15 +1659,15 @@ OggOpusFile *op_open_memory(const unsigned char *_data,size_t _size,
/*Convenience routine to clean up from failure for the open functions that
create their own streams.*/
static OggOpusFile *op_test_close_on_failure(void *_source,
static OggOpusFile *op_test_close_on_failure(void *_stream,
const OpusFileCallbacks *_cb,int *_error){
OggOpusFile *of;
if(OP_UNLIKELY(_source==NULL)){
if(OP_UNLIKELY(_stream==NULL)){
if(_error!=NULL)*_error=OP_EFAULT;
return NULL;
}
of=op_test_callbacks(_source,_cb,NULL,0,_error);
if(OP_UNLIKELY(of==NULL))(*_cb->close)(_source);
of=op_test_callbacks(_stream,_cb,NULL,0,_error);
if(OP_UNLIKELY(of==NULL))(*_cb->close)(_stream);
return of;
}
@ -1702,7 +1708,7 @@ int op_link_count(const OggOpusFile *_of){
return _of->nlinks;
}
ogg_uint32_t op_serialno(const OggOpusFile *_of,int _li){
opus_uint32 op_serialno(const OggOpusFile *_of,int _li){
if(OP_UNLIKELY(_li>=_of->nlinks))_li=_of->nlinks-1;
if(!_of->seekable)_li=0;
return _of->links[_li<0?_of->cur_link:_li].serialno;
@ -1718,13 +1724,14 @@ opus_int64 op_raw_total(const OggOpusFile *_of,int _li){
||OP_UNLIKELY(_li>=_of->nlinks)){
return OP_EINVAL;
}
if(_li<0)return _of->end-_of->links[0].offset;
if(_li<0)return _of->end;
return (_li+1>=_of->nlinks?_of->end:_of->links[_li+1].offset)
-_of->links[_li].offset;
-(_li>0?_of->links[_li].offset:0);
}
ogg_int64_t op_pcm_total(const OggOpusFile *_of,int _li){
OggOpusLink *links;
ogg_int64_t pcm_total;
ogg_int64_t diff=0;
int nlinks;
nlinks=_of->nlinks;
@ -1737,20 +1744,14 @@ ogg_int64_t op_pcm_total(const OggOpusFile *_of,int _li){
/*We verify that the granule position differences are larger than the
pre-skip and that the total duration does not overflow during link
enumeration, so we don't have to check here.*/
pcm_total=0;
if(_li<0){
ogg_int64_t pcm_total;
int li;
pcm_total=0;
for(li=0;li<nlinks;li++){
OP_ALWAYS_TRUE(!op_granpos_diff(&diff,
links[li].pcm_end,links[li].pcm_start));
pcm_total+=diff-links[li].head.pre_skip;
}
return pcm_total;
pcm_total=links[nlinks-1].pcm_file_offset;
_li=nlinks-1;
}
OP_ALWAYS_TRUE(!op_granpos_diff(&diff,
links[_li].pcm_end,links[_li].pcm_start));
return diff-links[_li].head.pre_skip;
return pcm_total+diff-links[_li].head.pre_skip;
}
const OpusHead *op_head(const OggOpusFile *_of,int _li){
@ -1820,6 +1821,34 @@ opus_int32 op_bitrate_instant(OggOpusFile *_of){
return ret;
}
/*Given a serialno, find a link with a corresponding Opus stream, if it exists.
Return: The index of the link to which the page belongs, or a negative number
if it was not a desired Opus bitstream section.*/
static int op_get_link_from_serialno(const OggOpusFile *_of,int _cur_link,
opus_int64 _page_offset,ogg_uint32_t _serialno){
const OggOpusLink *links;
int nlinks;
int li_lo;
int li_hi;
OP_ASSERT(_of->seekable);
links=_of->links;
nlinks=_of->nlinks;
li_lo=0;
/*Start off by guessing we're just a multiplexed page in the current link.*/
li_hi=_cur_link+1<nlinks&&_page_offset<links[nlinks+1].offset?
_cur_link+1:nlinks;
do{
if(_page_offset>=links[_cur_link].offset)li_lo=_cur_link;
else li_hi=_cur_link;
_cur_link=li_lo+(li_hi-li_lo>>1);
}
while(li_hi-li_lo>1);
/*We've identified the link that should contain this page.
Make sure it's a page we care about.*/
if(links[_cur_link].serialno!=_serialno)return OP_FALSE;
return _cur_link;
}
/*Fetch and process a page.
This handles the case where we're at a bitstream boundary and dumps the
decoding machine.
@ -1876,19 +1905,28 @@ static int op_fetch_and_process_page(OggOpusFile *_of,
if(OP_UNLIKELY(_of->ready_state<OP_STREAMSET)){
if(seekable){
ogg_uint32_t serialno;
int nlinks;
int li;
serialno=ogg_page_serialno(&og);
/*Match the serialno to bitstream section.
We use this rather than offset positions to avoid problems near
logical bitstream boundaries.*/
nlinks=_of->nlinks;
for(li=0;li<nlinks&&links[li].serialno!=serialno;li++);
/*Not a desired Opus bitstream section.
Keep trying.*/
if(li>=nlinks)continue;
/*Match the serialno to bitstream section.*/
OP_ASSERT(cur_link>=0&&cur_link<_of->nlinks);
if(links[cur_link].serialno!=serialno){
/*It wasn't a page from the current link.
Is it from the next one?*/
if(OP_LIKELY(cur_link+1<_of->nlinks&&links[cur_link+1].serialno==
serialno)){
cur_link++;
}
else{
int new_link;
new_link=
op_get_link_from_serialno(_of,cur_link,_page_offset,serialno);
/*Not a desired Opus bitstream section.
Keep trying.*/
if(new_link<0)continue;
cur_link=new_link;
}
}
cur_serialno=serialno;
_of->cur_link=cur_link=li;
_of->cur_link=cur_link;
ogg_stream_reset_serialno(&_of->os,serialno);
_of->ready_state=OP_STREAMSET;
/*If we're at the start of this link, initialize the granule position
@ -1942,13 +1980,32 @@ static int op_fetch_and_process_page(OggOpusFile *_of,
opus_int32 total_duration;
int durations[255];
int op_count;
int report_hole;
report_hole=0;
total_duration=op_collect_audio_packets(_of,durations);
if(OP_UNLIKELY(total_duration<0)){
/*Drain the packets from the page anyway.*/
/*libogg reported a hole (a gap in the page sequence numbers).
Drain the packets from the page anyway.
If we don't, they'll still be there when we fetch the next page.
Then, when we go to pull out packets, we might get more than 255,
which would overrun our packet buffer.*/
total_duration=op_collect_audio_packets(_of,durations);
OP_ASSERT(total_duration>=0);
/*Report holes to the caller.*/
if(!_ignore_holes)return OP_HOLE;
if(!_ignore_holes){
/*Report the hole to the caller after we finish timestamping the
packets.*/
report_hole=1;
/*We had lost or damaged pages, so reset our granule position
tracking.
This makes holes behave the same as a small raw seek.
If the next page is the EOS page, we'll discard it (because we
can't perform end trimming properly), and we'll always discard at
least 80 ms of audio (to allow decoder state to re-converge).
We could try to fill in the gap with PLC by looking at timestamps
in the non-EOS case, but that's complicated and error prone and we
can't rely on the timestamps being valid.*/
_of->prev_packet_gp=-1;
}
}
op_count=_of->op_count;
/*If we found at least one audio data packet, compute per-packet granule
@ -1975,6 +2032,7 @@ static int op_fetch_and_process_page(OggOpusFile *_of,
Proceed to the next link, rather than risk playing back some
samples that shouldn't have been played.*/
_of->op_count=0;
if(report_hole)return OP_HOLE;
continue;
}
/*By default discard 80 ms of data after a seek, unless we seek
@ -2076,10 +2134,11 @@ static int op_fetch_and_process_page(OggOpusFile *_of,
}
_of->prev_packet_gp=prev_packet_gp;
_of->prev_page_offset=_page_offset;
_of->op_count=pi;
/*If end-trimming didn't trim all the packets, we're done.*/
if(OP_LIKELY(pi>0))return 0;
_of->op_count=op_count=pi;
}
if(report_hole)return OP_HOLE;
/*If end-trimming didn't trim all the packets, we're done.*/
if(op_count>0)return 0;
}
}
}
@ -2117,35 +2176,41 @@ static ogg_int64_t op_get_granulepos(const OggOpusFile *_of,
ogg_int64_t _pcm_offset,int *_li){
const OggOpusLink *links;
ogg_int64_t duration=0;
ogg_int64_t pcm_start;
opus_int32 pre_skip;
int nlinks;
int li;
int li_lo;
int li_hi;
OP_ASSERT(_pcm_offset>=0);
nlinks=_of->nlinks;
links=_of->links;
for(li=0;OP_LIKELY(li<nlinks);li++){
ogg_int64_t pcm_start;
opus_int32 pre_skip;
pcm_start=links[li].pcm_start;
pre_skip=links[li].head.pre_skip;
OP_ALWAYS_TRUE(!op_granpos_diff(&duration,links[li].pcm_end,pcm_start));
duration-=pre_skip;
if(_pcm_offset<duration){
_pcm_offset+=pre_skip;
if(OP_UNLIKELY(pcm_start>OP_INT64_MAX-_pcm_offset)){
/*Adding this amount to the granule position would overflow the positive
half of its 64-bit range.
Since signed overflow is undefined in C, do it in a way the compiler
isn't allowed to screw up.*/
_pcm_offset-=OP_INT64_MAX-pcm_start+1;
pcm_start=OP_INT64_MIN;
}
pcm_start+=_pcm_offset;
*_li=li;
return pcm_start;
}
_pcm_offset-=duration;
li_lo=0;
li_hi=nlinks;
do{
int li;
li=li_lo+(li_hi-li_lo>>1);
if(links[li].pcm_file_offset<=_pcm_offset)li_lo=li;
else li_hi=li;
}
return -1;
while(li_hi-li_lo>1);
_pcm_offset-=links[li_lo].pcm_file_offset;
pcm_start=links[li_lo].pcm_start;
pre_skip=links[li_lo].head.pre_skip;
OP_ALWAYS_TRUE(!op_granpos_diff(&duration,links[li_lo].pcm_end,pcm_start));
duration-=pre_skip;
if(_pcm_offset>=duration)return -1;
_pcm_offset+=pre_skip;
if(OP_UNLIKELY(pcm_start>OP_INT64_MAX-_pcm_offset)){
/*Adding this amount to the granule position would overflow the positive
half of its 64-bit range.
Since signed overflow is undefined in C, do it in a way the compiler
isn't allowed to screw up.*/
_pcm_offset-=OP_INT64_MAX-pcm_start+1;
pcm_start=OP_INT64_MIN;
}
pcm_start+=_pcm_offset;
*_li=li_lo;
return pcm_start;
}
/*A small helper to determine if an Ogg page contains data that continues onto
@ -2193,7 +2258,7 @@ static int op_pcm_seek_page(OggOpusFile *_of,
ogg_int64_t pcm_start;
ogg_int64_t pcm_end;
ogg_int64_t best_gp;
ogg_int64_t diff=0;
ogg_int64_t diff;
ogg_uint32_t serialno;
opus_int32 pre_skip;
opus_int64 begin;
@ -2331,7 +2396,7 @@ static int op_pcm_seek_page(OggOpusFile *_of,
d2=end-begin>>1;
if(force_bisect)bisect=begin+(end-begin>>1);
else{
ogg_int64_t diff2=0;
ogg_int64_t diff2;
OP_ALWAYS_TRUE(!op_granpos_diff(&diff,_target_gp,pcm_start));
OP_ALWAYS_TRUE(!op_granpos_diff(&diff2,pcm_end,pcm_start));
/*Take a (pretty decent) guess.*/
@ -2606,22 +2671,14 @@ static ogg_int64_t op_get_pcm_offset(const OggOpusFile *_of,
ogg_int64_t _gp,int _li){
const OggOpusLink *links;
ogg_int64_t pcm_offset;
ogg_int64_t delta=0;
int li;
links=_of->links;
pcm_offset=0;
OP_ASSERT(_li<_of->nlinks);
for(li=0;li<_li;li++){
OP_ALWAYS_TRUE(!op_granpos_diff(&delta,
links[li].pcm_end,links[li].pcm_start));
delta-=links[li].head.pre_skip;
pcm_offset+=delta;
}
OP_ASSERT(_li>=0);
OP_ASSERT(_li>=0&&_li<_of->nlinks);
pcm_offset=links[_li].pcm_file_offset;
if(_of->seekable&&OP_UNLIKELY(op_granpos_cmp(_gp,links[_li].pcm_end)>0)){
_gp=links[_li].pcm_end;
}
if(OP_LIKELY(op_granpos_cmp(_gp,links[_li].pcm_start)>0)){
ogg_int64_t delta;
if(OP_UNLIKELY(op_granpos_diff(&delta,_gp,links[_li].pcm_start)<0)){
/*This means an unseekable stream claimed to have a page from more than
2 billion days after we joined.*/