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-rw-r--r--vorbis/lib/vorbisfile.c2424
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diff --git a/vorbis/lib/vorbisfile.c b/vorbis/lib/vorbisfile.c
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+++ b/vorbis/lib/vorbisfile.c
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+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2015 *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function: stdio-based convenience library for opening/seeking/decoding
+
+ ********************************************************************/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <math.h>
+
+#include "vorbis/codec.h"
+
+/* we don't need or want the static callback symbols here */
+#define OV_EXCLUDE_STATIC_CALLBACKS
+#include "vorbis/vorbisfile.h"
+
+#include "os.h"
+#include "misc.h"
+
+/* A 'chained bitstream' is a Vorbis bitstream that contains more than
+ one logical bitstream arranged end to end (the only form of Ogg
+ multiplexing allowed in a Vorbis bitstream; grouping [parallel
+ multiplexing] is not allowed in Vorbis) */
+
+/* A Vorbis file can be played beginning to end (streamed) without
+ worrying ahead of time about chaining (see decoder_example.c). If
+ we have the whole file, however, and want random access
+ (seeking/scrubbing) or desire to know the total length/time of a
+ file, we need to account for the possibility of chaining. */
+
+/* We can handle things a number of ways; we can determine the entire
+ bitstream structure right off the bat, or find pieces on demand.
+ This example determines and caches structure for the entire
+ bitstream, but builds a virtual decoder on the fly when moving
+ between links in the chain. */
+
+/* There are also different ways to implement seeking. Enough
+ information exists in an Ogg bitstream to seek to
+ sample-granularity positions in the output. Or, one can seek by
+ picking some portion of the stream roughly in the desired area if
+ we only want coarse navigation through the stream. */
+
+/*************************************************************************
+ * Many, many internal helpers. The intention is not to be confusing;
+ * rampant duplication and monolithic function implementation would be
+ * harder to understand anyway. The high level functions are last. Begin
+ * grokking near the end of the file */
+
+/* read a little more data from the file/pipe into the ogg_sync framer
+*/
+#define CHUNKSIZE 65536 /* greater-than-page-size granularity seeking */
+#define READSIZE 2048 /* a smaller read size is needed for low-rate streaming. */
+
+static long _get_data(OggVorbis_File *vf){
+ errno=0;
+ if(!(vf->callbacks.read_func))return(-1);
+ if(vf->datasource){
+ char *buffer=ogg_sync_buffer(&vf->oy,READSIZE);
+ long bytes=(vf->callbacks.read_func)(buffer,1,READSIZE,vf->datasource);
+ if(bytes>0)ogg_sync_wrote(&vf->oy,bytes);
+ if(bytes==0 && errno)return(-1);
+ return(bytes);
+ }else
+ return(0);
+}
+
+/* save a tiny smidge of verbosity to make the code more readable */
+static int _seek_helper(OggVorbis_File *vf,ogg_int64_t offset){
+ if(vf->datasource){
+ /* only seek if the file position isn't already there */
+ if(vf->offset != offset){
+ if(!(vf->callbacks.seek_func)||
+ (vf->callbacks.seek_func)(vf->datasource, offset, SEEK_SET) == -1)
+ return OV_EREAD;
+ vf->offset=offset;
+ ogg_sync_reset(&vf->oy);
+ }
+ }else{
+ /* shouldn't happen unless someone writes a broken callback */
+ return OV_EFAULT;
+ }
+ return 0;
+}
+
+/* The read/seek functions track absolute position within the stream */
+
+/* from the head of the stream, get the next page. boundary specifies
+ if the function is allowed to fetch more data from the stream (and
+ how much) or only use internally buffered data.
+
+ boundary: -1) unbounded search
+ 0) read no additional data; use cached only
+ n) search for a new page beginning for n bytes
+
+ return: <0) did not find a page (OV_FALSE, OV_EOF, OV_EREAD)
+ n) found a page at absolute offset n */
+
+static ogg_int64_t _get_next_page(OggVorbis_File *vf,ogg_page *og,
+ ogg_int64_t boundary){
+ if(boundary>0)boundary+=vf->offset;
+ while(1){
+ long more;
+
+ if(boundary>0 && vf->offset>=boundary)return(OV_FALSE);
+ more=ogg_sync_pageseek(&vf->oy,og);
+
+ if(more<0){
+ /* skipped n bytes */
+ vf->offset-=more;
+ }else{
+ if(more==0){
+ /* send more paramedics */
+ if(!boundary)return(OV_FALSE);
+ {
+ long ret=_get_data(vf);
+ if(ret==0)return(OV_EOF);
+ if(ret<0)return(OV_EREAD);
+ }
+ }else{
+ /* got a page. Return the offset at the page beginning,
+ advance the internal offset past the page end */
+ ogg_int64_t ret=vf->offset;
+ vf->offset+=more;
+ return(ret);
+
+ }
+ }
+ }
+}
+
+/* find the latest page beginning before the passed in position. Much
+ dirtier than the above as Ogg doesn't have any backward search
+ linkage. no 'readp' as it will certainly have to read. */
+/* returns offset or OV_EREAD, OV_FAULT */
+static ogg_int64_t _get_prev_page(OggVorbis_File *vf,ogg_int64_t begin,ogg_page *og){
+ ogg_int64_t end = begin;
+ ogg_int64_t ret;
+ ogg_int64_t offset=-1;
+
+ while(offset==-1){
+ begin-=CHUNKSIZE;
+ if(begin<0)
+ begin=0;
+
+ ret=_seek_helper(vf,begin);
+ if(ret)return(ret);
+
+ while(vf->offset<end){
+ memset(og,0,sizeof(*og));
+ ret=_get_next_page(vf,og,end-vf->offset);
+ if(ret==OV_EREAD)return(OV_EREAD);
+ if(ret<0){
+ break;
+ }else{
+ offset=ret;
+ }
+ }
+ }
+
+ /* In a fully compliant, non-multiplexed stream, we'll still be
+ holding the last page. In multiplexed (or noncompliant streams),
+ we will probably have to re-read the last page we saw */
+ if(og->header_len==0){
+ ret=_seek_helper(vf,offset);
+ if(ret)return(ret);
+
+ ret=_get_next_page(vf,og,CHUNKSIZE);
+ if(ret<0)
+ /* this shouldn't be possible */
+ return(OV_EFAULT);
+ }
+
+ return(offset);
+}
+
+static void _add_serialno(ogg_page *og,long **serialno_list, int *n){
+ long s = ogg_page_serialno(og);
+ (*n)++;
+
+ if(*serialno_list){
+ *serialno_list = _ogg_realloc(*serialno_list, sizeof(**serialno_list)*(*n));
+ }else{
+ *serialno_list = _ogg_malloc(sizeof(**serialno_list));
+ }
+
+ (*serialno_list)[(*n)-1] = s;
+}
+
+/* returns nonzero if found */
+static int _lookup_serialno(long s, long *serialno_list, int n){
+ if(serialno_list){
+ while(n--){
+ if(*serialno_list == s) return 1;
+ serialno_list++;
+ }
+ }
+ return 0;
+}
+
+static int _lookup_page_serialno(ogg_page *og, long *serialno_list, int n){
+ long s = ogg_page_serialno(og);
+ return _lookup_serialno(s,serialno_list,n);
+}
+
+/* performs the same search as _get_prev_page, but prefers pages of
+ the specified serial number. If a page of the specified serialno is
+ spotted during the seek-back-and-read-forward, it will return the
+ info of last page of the matching serial number instead of the very
+ last page. If no page of the specified serialno is seen, it will
+ return the info of last page and alter *serialno. */
+static ogg_int64_t _get_prev_page_serial(OggVorbis_File *vf, ogg_int64_t begin,
+ long *serial_list, int serial_n,
+ int *serialno, ogg_int64_t *granpos){
+ ogg_page og;
+ ogg_int64_t end=begin;
+ ogg_int64_t ret;
+
+ ogg_int64_t prefoffset=-1;
+ ogg_int64_t offset=-1;
+ ogg_int64_t ret_serialno=-1;
+ ogg_int64_t ret_gran=-1;
+
+ while(offset==-1){
+ begin-=CHUNKSIZE;
+ if(begin<0)
+ begin=0;
+
+ ret=_seek_helper(vf,begin);
+ if(ret)return(ret);
+
+ while(vf->offset<end){
+ ret=_get_next_page(vf,&og,end-vf->offset);
+ if(ret==OV_EREAD)return(OV_EREAD);
+ if(ret<0){
+ break;
+ }else{
+ ret_serialno=ogg_page_serialno(&og);
+ ret_gran=ogg_page_granulepos(&og);
+ offset=ret;
+
+ if(ret_serialno == *serialno){
+ prefoffset=ret;
+ *granpos=ret_gran;
+ }
+
+ if(!_lookup_serialno(ret_serialno,serial_list,serial_n)){
+ /* we fell off the end of the link, which means we seeked
+ back too far and shouldn't have been looking in that link
+ to begin with. If we found the preferred serial number,
+ forget that we saw it. */
+ prefoffset=-1;
+ }
+ }
+ }
+ }
+
+ /* we're not interested in the page... just the serialno and granpos. */
+ if(prefoffset>=0)return(prefoffset);
+
+ *serialno = ret_serialno;
+ *granpos = ret_gran;
+ return(offset);
+
+}
+
+/* uses the local ogg_stream storage in vf; this is important for
+ non-streaming input sources */
+static int _fetch_headers(OggVorbis_File *vf,vorbis_info *vi,vorbis_comment *vc,
+ long **serialno_list, int *serialno_n,
+ ogg_page *og_ptr){
+ ogg_page og;
+ ogg_packet op;
+ int i,ret;
+ int allbos=0;
+
+ if(!og_ptr){
+ ogg_int64_t llret=_get_next_page(vf,&og,CHUNKSIZE);
+ if(llret==OV_EREAD)return(OV_EREAD);
+ if(llret<0)return(OV_ENOTVORBIS);
+ og_ptr=&og;
+ }
+
+ vorbis_info_init(vi);
+ vorbis_comment_init(vc);
+ vf->ready_state=OPENED;
+
+ /* extract the serialnos of all BOS pages + the first set of vorbis
+ headers we see in the link */
+
+ while(ogg_page_bos(og_ptr)){
+ if(serialno_list){
+ if(_lookup_page_serialno(og_ptr,*serialno_list,*serialno_n)){
+ /* a dupe serialnumber in an initial header packet set == invalid stream */
+ if(*serialno_list)_ogg_free(*serialno_list);
+ *serialno_list=0;
+ *serialno_n=0;
+ ret=OV_EBADHEADER;
+ goto bail_header;
+ }
+
+ _add_serialno(og_ptr,serialno_list,serialno_n);
+ }
+
+ if(vf->ready_state<STREAMSET){
+ /* we don't have a vorbis stream in this link yet, so begin
+ prospective stream setup. We need a stream to get packets */
+ ogg_stream_reset_serialno(&vf->os,ogg_page_serialno(og_ptr));
+ ogg_stream_pagein(&vf->os,og_ptr);
+
+ if(ogg_stream_packetout(&vf->os,&op) > 0 &&
+ vorbis_synthesis_idheader(&op)){
+ /* vorbis header; continue setup */
+ vf->ready_state=STREAMSET;
+ if((ret=vorbis_synthesis_headerin(vi,vc,&op))){
+ ret=OV_EBADHEADER;
+ goto bail_header;
+ }
+ }
+ }
+
+ /* get next page */
+ {
+ ogg_int64_t llret=_get_next_page(vf,og_ptr,CHUNKSIZE);
+ if(llret==OV_EREAD){
+ ret=OV_EREAD;
+ goto bail_header;
+ }
+ if(llret<0){
+ ret=OV_ENOTVORBIS;
+ goto bail_header;
+ }
+
+ /* if this page also belongs to our vorbis stream, submit it and break */
+ if(vf->ready_state==STREAMSET &&
+ vf->os.serialno == ogg_page_serialno(og_ptr)){
+ ogg_stream_pagein(&vf->os,og_ptr);
+ break;
+ }
+ }
+ }
+
+ if(vf->ready_state!=STREAMSET){
+ ret = OV_ENOTVORBIS;
+ goto bail_header;
+ }
+
+ while(1){
+
+ i=0;
+ while(i<2){ /* get a page loop */
+
+ while(i<2){ /* get a packet loop */
+
+ int result=ogg_stream_packetout(&vf->os,&op);
+ if(result==0)break;
+ if(result==-1){
+ ret=OV_EBADHEADER;
+ goto bail_header;
+ }
+
+ if((ret=vorbis_synthesis_headerin(vi,vc,&op)))
+ goto bail_header;
+
+ i++;
+ }
+
+ while(i<2){
+ if(_get_next_page(vf,og_ptr,CHUNKSIZE)<0){
+ ret=OV_EBADHEADER;
+ goto bail_header;
+ }
+
+ /* if this page belongs to the correct stream, go parse it */
+ if(vf->os.serialno == ogg_page_serialno(og_ptr)){
+ ogg_stream_pagein(&vf->os,og_ptr);
+ break;
+ }
+
+ /* if we never see the final vorbis headers before the link
+ ends, abort */
+ if(ogg_page_bos(og_ptr)){
+ if(allbos){
+ ret = OV_EBADHEADER;
+ goto bail_header;
+ }else
+ allbos=1;
+ }
+
+ /* otherwise, keep looking */
+ }
+ }
+
+ return 0;
+ }
+
+ bail_header:
+ vorbis_info_clear(vi);
+ vorbis_comment_clear(vc);
+ vf->ready_state=OPENED;
+
+ return ret;
+}
+
+/* Starting from current cursor position, get initial PCM offset of
+ next page. Consumes the page in the process without decoding
+ audio, however this is only called during stream parsing upon
+ seekable open. */
+static ogg_int64_t _initial_pcmoffset(OggVorbis_File *vf, vorbis_info *vi){
+ ogg_page og;
+ ogg_int64_t accumulated=0;
+ long lastblock=-1;
+ int result;
+ int serialno = vf->os.serialno;
+
+ while(1){
+ ogg_packet op;
+ if(_get_next_page(vf,&og,-1)<0)
+ break; /* should not be possible unless the file is truncated/mangled */
+
+ if(ogg_page_bos(&og)) break;
+ if(ogg_page_serialno(&og)!=serialno) continue;
+
+ /* count blocksizes of all frames in the page */
+ ogg_stream_pagein(&vf->os,&og);
+ while((result=ogg_stream_packetout(&vf->os,&op))){
+ if(result>0){ /* ignore holes */
+ long thisblock=vorbis_packet_blocksize(vi,&op);
+ if(thisblock>=0){
+ if(lastblock!=-1)
+ accumulated+=(lastblock+thisblock)>>2;
+ lastblock=thisblock;
+ }
+ }
+ }
+
+ if(ogg_page_granulepos(&og)!=-1){
+ /* pcm offset of last packet on the first audio page */
+ accumulated= ogg_page_granulepos(&og)-accumulated;
+ break;
+ }
+ }
+
+ /* less than zero? Either a corrupt file or a stream with samples
+ trimmed off the beginning, a normal occurrence; in both cases set
+ the offset to zero */
+ if(accumulated<0)accumulated=0;
+
+ return accumulated;
+}
+
+/* finds each bitstream link one at a time using a bisection search
+ (has to begin by knowing the offset of the lb's initial page).
+ Recurses for each link so it can alloc the link storage after
+ finding them all, then unroll and fill the cache at the same time */
+static int _bisect_forward_serialno(OggVorbis_File *vf,
+ ogg_int64_t begin,
+ ogg_int64_t searched,
+ ogg_int64_t end,
+ ogg_int64_t endgran,
+ int endserial,
+ long *currentno_list,
+ int currentnos,
+ long m){
+ ogg_int64_t pcmoffset;
+ ogg_int64_t dataoffset=searched;
+ ogg_int64_t endsearched=end;
+ ogg_int64_t next=end;
+ ogg_int64_t searchgran=-1;
+ ogg_page og;
+ ogg_int64_t ret,last;
+ int serialno = vf->os.serialno;
+
+ /* invariants:
+ we have the headers and serialnos for the link beginning at 'begin'
+ we have the offset and granpos of the last page in the file (potentially
+ not a page we care about)
+ */
+
+ /* Is the last page in our list of current serialnumbers? */
+ if(_lookup_serialno(endserial,currentno_list,currentnos)){
+
+ /* last page is in the starting serialno list, so we've bisected
+ down to (or just started with) a single link. Now we need to
+ find the last vorbis page belonging to the first vorbis stream
+ for this link. */
+ searched = end;
+ while(endserial != serialno){
+ endserial = serialno;
+ searched=_get_prev_page_serial(vf,searched,currentno_list,currentnos,&endserial,&endgran);
+ }
+
+ vf->links=m+1;
+ if(vf->offsets)_ogg_free(vf->offsets);
+ if(vf->serialnos)_ogg_free(vf->serialnos);
+ if(vf->dataoffsets)_ogg_free(vf->dataoffsets);
+
+ vf->offsets=_ogg_malloc((vf->links+1)*sizeof(*vf->offsets));
+ vf->vi=_ogg_realloc(vf->vi,vf->links*sizeof(*vf->vi));
+ vf->vc=_ogg_realloc(vf->vc,vf->links*sizeof(*vf->vc));
+ vf->serialnos=_ogg_malloc(vf->links*sizeof(*vf->serialnos));
+ vf->dataoffsets=_ogg_malloc(vf->links*sizeof(*vf->dataoffsets));
+ vf->pcmlengths=_ogg_malloc(vf->links*2*sizeof(*vf->pcmlengths));
+
+ vf->offsets[m+1]=end;
+ vf->offsets[m]=begin;
+ vf->pcmlengths[m*2+1]=(endgran<0?0:endgran);
+
+ }else{
+
+ /* last page is not in the starting stream's serial number list,
+ so we have multiple links. Find where the stream that begins
+ our bisection ends. */
+
+ long *next_serialno_list=NULL;
+ int next_serialnos=0;
+ vorbis_info vi;
+ vorbis_comment vc;
+ int testserial = serialno+1;
+
+ /* the below guards against garbage seperating the last and
+ first pages of two links. */
+ while(searched<endsearched){
+ ogg_int64_t bisect;
+
+ if(endsearched-searched<CHUNKSIZE){
+ bisect=searched;
+ }else{
+ bisect=(searched+endsearched)/2;
+ }
+
+ ret=_seek_helper(vf,bisect);
+ if(ret)return(ret);
+
+ last=_get_next_page(vf,&og,-1);
+ if(last==OV_EREAD)return(OV_EREAD);
+ if(last<0 || !_lookup_page_serialno(&og,currentno_list,currentnos)){
+ endsearched=bisect;
+ if(last>=0)next=last;
+ }else{
+ searched=vf->offset;
+ }
+ }
+
+ /* Bisection point found */
+ /* for the time being, fetch end PCM offset the simple way */
+ searched = next;
+ while(testserial != serialno){
+ testserial = serialno;
+ searched = _get_prev_page_serial(vf,searched,currentno_list,currentnos,&testserial,&searchgran);
+ }
+
+ ret=_seek_helper(vf,next);
+ if(ret)return(ret);
+
+ ret=_fetch_headers(vf,&vi,&vc,&next_serialno_list,&next_serialnos,NULL);
+ if(ret)return(ret);
+ serialno = vf->os.serialno;
+ dataoffset = vf->offset;
+
+ /* this will consume a page, however the next bisection always
+ starts with a raw seek */
+ pcmoffset = _initial_pcmoffset(vf,&vi);
+
+ ret=_bisect_forward_serialno(vf,next,vf->offset,end,endgran,endserial,
+ next_serialno_list,next_serialnos,m+1);
+ if(ret)return(ret);
+
+ if(next_serialno_list)_ogg_free(next_serialno_list);
+
+ vf->offsets[m+1]=next;
+ vf->serialnos[m+1]=serialno;
+ vf->dataoffsets[m+1]=dataoffset;
+
+ vf->vi[m+1]=vi;
+ vf->vc[m+1]=vc;
+
+ vf->pcmlengths[m*2+1]=searchgran;
+ vf->pcmlengths[m*2+2]=pcmoffset;
+ vf->pcmlengths[m*2+3]-=pcmoffset;
+ if(vf->pcmlengths[m*2+3]<0)vf->pcmlengths[m*2+3]=0;
+ }
+ return(0);
+}
+
+static int _make_decode_ready(OggVorbis_File *vf){
+ if(vf->ready_state>STREAMSET)return 0;
+ if(vf->ready_state<STREAMSET)return OV_EFAULT;
+ if(vf->seekable){
+ if(vorbis_synthesis_init(&vf->vd,vf->vi+vf->current_link))
+ return OV_EBADLINK;
+ }else{
+ if(vorbis_synthesis_init(&vf->vd,vf->vi))
+ return OV_EBADLINK;
+ }
+ vorbis_block_init(&vf->vd,&vf->vb);
+ vf->ready_state=INITSET;
+ vf->bittrack=0.f;
+ vf->samptrack=0.f;
+ return 0;
+}
+
+static int _open_seekable2(OggVorbis_File *vf){
+ ogg_int64_t dataoffset=vf->dataoffsets[0],end,endgran=-1;
+ int endserial=vf->os.serialno;
+ int serialno=vf->os.serialno;
+
+ /* we're partially open and have a first link header state in
+ storage in vf */
+
+ /* fetch initial PCM offset */
+ ogg_int64_t pcmoffset = _initial_pcmoffset(vf,vf->vi);
+
+ /* we can seek, so set out learning all about this file */
+ if(vf->callbacks.seek_func && vf->callbacks.tell_func){
+ (vf->callbacks.seek_func)(vf->datasource,0,SEEK_END);
+ vf->offset=vf->end=(vf->callbacks.tell_func)(vf->datasource);
+ }else{
+ vf->offset=vf->end=-1;
+ }
+
+ /* If seek_func is implemented, tell_func must also be implemented */
+ if(vf->end==-1) return(OV_EINVAL);
+
+ /* Get the offset of the last page of the physical bitstream, or, if
+ we're lucky the last vorbis page of this link as most OggVorbis
+ files will contain a single logical bitstream */
+ end=_get_prev_page_serial(vf,vf->end,vf->serialnos+2,vf->serialnos[1],&endserial,&endgran);
+ if(end<0)return(end);
+
+ /* now determine bitstream structure recursively */
+ if(_bisect_forward_serialno(vf,0,dataoffset,end,endgran,endserial,
+ vf->serialnos+2,vf->serialnos[1],0)<0)return(OV_EREAD);
+
+ vf->offsets[0]=0;
+ vf->serialnos[0]=serialno;
+ vf->dataoffsets[0]=dataoffset;
+ vf->pcmlengths[0]=pcmoffset;
+ vf->pcmlengths[1]-=pcmoffset;
+ if(vf->pcmlengths[1]<0)vf->pcmlengths[1]=0;
+
+ return(ov_raw_seek(vf,dataoffset));
+}
+
+/* clear out the current logical bitstream decoder */
+static void _decode_clear(OggVorbis_File *vf){
+ vorbis_dsp_clear(&vf->vd);
+ vorbis_block_clear(&vf->vb);
+ vf->ready_state=OPENED;
+}
+
+/* fetch and process a packet. Handles the case where we're at a
+ bitstream boundary and dumps the decoding machine. If the decoding
+ machine is unloaded, it loads it. It also keeps pcm_offset up to
+ date (seek and read both use this. seek uses a special hack with
+ readp).
+
+ return: <0) error, OV_HOLE (lost packet) or OV_EOF
+ 0) need more data (only if readp==0)
+ 1) got a packet
+*/
+
+static int _fetch_and_process_packet(OggVorbis_File *vf,
+ ogg_packet *op_in,
+ int readp,
+ int spanp){
+ ogg_page og;
+
+ /* handle one packet. Try to fetch it from current stream state */
+ /* extract packets from page */
+ while(1){
+
+ if(vf->ready_state==STREAMSET){
+ int ret=_make_decode_ready(vf);
+ if(ret<0)return ret;
+ }
+
+ /* process a packet if we can. */
+
+ if(vf->ready_state==INITSET){
+ int hs=vorbis_synthesis_halfrate_p(vf->vi);
+
+ while(1) {
+ ogg_packet op;
+ ogg_packet *op_ptr=(op_in?op_in:&op);
+ int result=ogg_stream_packetout(&vf->os,op_ptr);
+ ogg_int64_t granulepos;
+
+ op_in=NULL;
+ if(result==-1)return(OV_HOLE); /* hole in the data. */
+ if(result>0){
+ /* got a packet. process it */
+ granulepos=op_ptr->granulepos;
+ if(!vorbis_synthesis(&vf->vb,op_ptr)){ /* lazy check for lazy
+ header handling. The
+ header packets aren't
+ audio, so if/when we
+ submit them,
+ vorbis_synthesis will
+ reject them */
+
+ /* suck in the synthesis data and track bitrate */
+ {
+ int oldsamples=vorbis_synthesis_pcmout(&vf->vd,NULL);
+ /* for proper use of libvorbis within libvorbisfile,
+ oldsamples will always be zero. */
+ if(oldsamples)return(OV_EFAULT);
+
+ vorbis_synthesis_blockin(&vf->vd,&vf->vb);
+ vf->samptrack+=(vorbis_synthesis_pcmout(&vf->vd,NULL)<<hs);
+ vf->bittrack+=op_ptr->bytes*8;
+ }
+
+ /* update the pcm offset. */
+ if(granulepos!=-1 && !op_ptr->e_o_s){
+ int link=(vf->seekable?vf->current_link:0);
+ int i,samples;
+
+ /* this packet has a pcm_offset on it (the last packet
+ completed on a page carries the offset) After processing
+ (above), we know the pcm position of the *last* sample
+ ready to be returned. Find the offset of the *first*
+
+ As an aside, this trick is inaccurate if we begin
+ reading anew right at the last page; the end-of-stream
+ granulepos declares the last frame in the stream, and the
+ last packet of the last page may be a partial frame.
+ So, we need a previous granulepos from an in-sequence page
+ to have a reference point. Thus the !op_ptr->e_o_s clause
+ above */
+
+ if(vf->seekable && link>0)
+ granulepos-=vf->pcmlengths[link*2];
+ if(granulepos<0)granulepos=0; /* actually, this
+ shouldn't be possible
+ here unless the stream
+ is very broken */
+
+ samples=(vorbis_synthesis_pcmout(&vf->vd,NULL)<<hs);
+
+ granulepos-=samples;
+ for(i=0;i<link;i++)
+ granulepos+=vf->pcmlengths[i*2+1];
+ vf->pcm_offset=granulepos;
+ }
+ return(1);
+ }
+ }
+ else
+ break;
+ }
+ }
+
+ if(vf->ready_state>=OPENED){
+ ogg_int64_t ret;
+
+ while(1){
+ /* the loop is not strictly necessary, but there's no sense in
+ doing the extra checks of the larger loop for the common
+ case in a multiplexed bistream where the page is simply
+ part of a different logical bitstream; keep reading until
+ we get one with the correct serialno */
+
+ if(!readp)return(0);
+ if((ret=_get_next_page(vf,&og,-1))<0){
+ return(OV_EOF); /* eof. leave unitialized */
+ }
+
+ /* bitrate tracking; add the header's bytes here, the body bytes
+ are done by packet above */
+ vf->bittrack+=og.header_len*8;
+
+ if(vf->ready_state==INITSET){
+ if(vf->current_serialno!=ogg_page_serialno(&og)){
+
+ /* two possibilities:
+ 1) our decoding just traversed a bitstream boundary
+ 2) another stream is multiplexed into this logical section */
+
+ if(ogg_page_bos(&og)){
+ /* boundary case */
+ if(!spanp)
+ return(OV_EOF);
+
+ _decode_clear(vf);
+
+ if(!vf->seekable){
+ vorbis_info_clear(vf->vi);
+ vorbis_comment_clear(vf->vc);
+ }
+ break;
+
+ }else
+ continue; /* possibility #2 */
+ }
+ }
+
+ break;
+ }
+ }
+
+ /* Do we need to load a new machine before submitting the page? */
+ /* This is different in the seekable and non-seekable cases.
+
+ In the seekable case, we already have all the header
+ information loaded and cached; we just initialize the machine
+ with it and continue on our merry way.
+
+ In the non-seekable (streaming) case, we'll only be at a
+ boundary if we just left the previous logical bitstream and
+ we're now nominally at the header of the next bitstream
+ */
+
+ if(vf->ready_state!=INITSET){
+ int link;
+
+ if(vf->ready_state<STREAMSET){
+ if(vf->seekable){
+ long 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 */
+
+ for(link=0;link<vf->links;link++)
+ if(vf->serialnos[link]==serialno)break;
+
+ if(link==vf->links) continue; /* not the desired Vorbis
+ bitstream section; keep
+ trying */
+
+ vf->current_serialno=serialno;
+ vf->current_link=link;
+
+ ogg_stream_reset_serialno(&vf->os,vf->current_serialno);
+ vf->ready_state=STREAMSET;
+
+ }else{
+ /* we're streaming */
+ /* fetch the three header packets, build the info struct */
+
+ int ret=_fetch_headers(vf,vf->vi,vf->vc,NULL,NULL,&og);
+ if(ret)return(ret);
+ vf->current_serialno=vf->os.serialno;
+ vf->current_link++;
+ link=0;
+ }
+ }
+ }
+
+ /* the buffered page is the data we want, and we're ready for it;
+ add it to the stream state */
+ ogg_stream_pagein(&vf->os,&og);
+
+ }
+}
+
+/* if, eg, 64 bit stdio is configured by default, this will build with
+ fseek64 */
+static int _fseek64_wrap(FILE *f,ogg_int64_t off,int whence){
+ if(f==NULL)return(-1);
+ return fseek(f,off,whence);
+}
+
+static int _ov_open1(void *f,OggVorbis_File *vf,const char *initial,
+ long ibytes, ov_callbacks callbacks){
+ int offsettest=((f && callbacks.seek_func)?callbacks.seek_func(f,0,SEEK_CUR):-1);
+ long *serialno_list=NULL;
+ int serialno_list_size=0;
+ int ret;
+
+ memset(vf,0,sizeof(*vf));
+ vf->datasource=f;
+ vf->callbacks = callbacks;
+
+ /* init the framing state */
+ ogg_sync_init(&vf->oy);
+
+ /* perhaps some data was previously read into a buffer for testing
+ against other stream types. Allow initialization from this
+ previously read data (especially as we may be reading from a
+ non-seekable stream) */
+ if(initial){
+ char *buffer=ogg_sync_buffer(&vf->oy,ibytes);
+ memcpy(buffer,initial,ibytes);
+ ogg_sync_wrote(&vf->oy,ibytes);
+ }
+
+ /* can we seek? Stevens suggests the seek test was portable */
+ if(offsettest!=-1)vf->seekable=1;
+
+ /* No seeking yet; Set up a 'single' (current) logical bitstream
+ entry for partial open */
+ vf->links=1;
+ vf->vi=_ogg_calloc(vf->links,sizeof(*vf->vi));
+ vf->vc=_ogg_calloc(vf->links,sizeof(*vf->vc));
+ ogg_stream_init(&vf->os,-1); /* fill in the serialno later */
+
+ /* Fetch all BOS pages, store the vorbis header and all seen serial
+ numbers, load subsequent vorbis setup headers */
+ if((ret=_fetch_headers(vf,vf->vi,vf->vc,&serialno_list,&serialno_list_size,NULL))<0){
+ vf->datasource=NULL;
+ ov_clear(vf);
+ }else{
+ /* serial number list for first link needs to be held somewhere
+ for second stage of seekable stream open; this saves having to
+ seek/reread first link's serialnumber data then. */
+ vf->serialnos=_ogg_calloc(serialno_list_size+2,sizeof(*vf->serialnos));
+ vf->serialnos[0]=vf->current_serialno=vf->os.serialno;
+ vf->serialnos[1]=serialno_list_size;
+ memcpy(vf->serialnos+2,serialno_list,serialno_list_size*sizeof(*vf->serialnos));
+
+ vf->offsets=_ogg_calloc(1,sizeof(*vf->offsets));
+ vf->dataoffsets=_ogg_calloc(1,sizeof(*vf->dataoffsets));
+ vf->offsets[0]=0;
+ vf->dataoffsets[0]=vf->offset;
+
+ vf->ready_state=PARTOPEN;
+ }
+ if(serialno_list)_ogg_free(serialno_list);
+ return(ret);
+}
+
+static int _ov_open2(OggVorbis_File *vf){
+ if(vf->ready_state != PARTOPEN) return OV_EINVAL;
+ vf->ready_state=OPENED;
+ if(vf->seekable){
+ int ret=_open_seekable2(vf);
+ if(ret){
+ vf->datasource=NULL;
+ ov_clear(vf);
+ }
+ return(ret);
+ }else
+ vf->ready_state=STREAMSET;
+
+ return 0;
+}
+
+
+/* clear out the OggVorbis_File struct */
+int ov_clear(OggVorbis_File *vf){
+ if(vf){
+ vorbis_block_clear(&vf->vb);
+ vorbis_dsp_clear(&vf->vd);
+ ogg_stream_clear(&vf->os);
+
+ if(vf->vi && vf->links){
+ int i;
+ for(i=0;i<vf->links;i++){
+ vorbis_info_clear(vf->vi+i);
+ vorbis_comment_clear(vf->vc+i);
+ }
+ _ogg_free(vf->vi);
+ _ogg_free(vf->vc);
+ }
+ if(vf->dataoffsets)_ogg_free(vf->dataoffsets);
+ if(vf->pcmlengths)_ogg_free(vf->pcmlengths);
+ if(vf->serialnos)_ogg_free(vf->serialnos);
+ if(vf->offsets)_ogg_free(vf->offsets);
+ ogg_sync_clear(&vf->oy);
+ if(vf->datasource && vf->callbacks.close_func)
+ (vf->callbacks.close_func)(vf->datasource);
+ memset(vf,0,sizeof(*vf));
+ }
+#ifdef DEBUG_LEAKS
+ _VDBG_dump();
+#endif
+ return(0);
+}
+
+/* inspects the OggVorbis file and finds/documents all the logical
+ bitstreams contained in it. Tries to be tolerant of logical
+ bitstream sections that are truncated/woogie.
+
+ return: -1) error
+ 0) OK
+*/
+
+int ov_open_callbacks(void *f,OggVorbis_File *vf,
+ const char *initial,long ibytes,ov_callbacks callbacks){
+ int ret=_ov_open1(f,vf,initial,ibytes,callbacks);
+ if(ret)return ret;
+ return _ov_open2(vf);
+}
+
+int ov_open(FILE *f,OggVorbis_File *vf,const char *initial,long ibytes){
+ ov_callbacks callbacks = {
+ (size_t (*)(void *, size_t, size_t, void *)) fread,
+ (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap,
+ (int (*)(void *)) fclose,
+ (long (*)(void *)) ftell
+ };
+
+ return ov_open_callbacks((void *)f, vf, initial, ibytes, callbacks);
+}
+
+int ov_fopen(const char *path,OggVorbis_File *vf){
+ int ret;
+ FILE *f = fopen(path,"rb");
+ if(!f) return -1;
+
+ ret = ov_open(f,vf,NULL,0);
+ if(ret) fclose(f);
+ return ret;
+}
+
+
+/* cheap hack for game usage where downsampling is desirable; there's
+ no need for SRC as we can just do it cheaply in libvorbis. */
+
+int ov_halfrate(OggVorbis_File *vf,int flag){
+ int i;
+ if(vf->vi==NULL)return OV_EINVAL;
+ if(vf->ready_state>STREAMSET){
+ /* clear out stream state; dumping the decode machine is needed to
+ reinit the MDCT lookups. */
+ vorbis_dsp_clear(&vf->vd);
+ vorbis_block_clear(&vf->vb);
+ vf->ready_state=STREAMSET;
+ if(vf->pcm_offset>=0){
+ ogg_int64_t pos=vf->pcm_offset;
+ vf->pcm_offset=-1; /* make sure the pos is dumped if unseekable */
+ ov_pcm_seek(vf,pos);
+ }
+ }
+
+ for(i=0;i<vf->links;i++){
+ if(vorbis_synthesis_halfrate(vf->vi+i,flag)){
+ if(flag) ov_halfrate(vf,0);
+ return OV_EINVAL;
+ }
+ }
+ return 0;
+}
+
+int ov_halfrate_p(OggVorbis_File *vf){
+ if(vf->vi==NULL)return OV_EINVAL;
+ return vorbis_synthesis_halfrate_p(vf->vi);
+}
+
+/* Only partially open the vorbis file; test for Vorbisness, and load
+ the headers for the first chain. Do not seek (although test for
+ seekability). Use ov_test_open to finish opening the file, else
+ ov_clear to close/free it. Same return codes as open.
+
+ Note that vorbisfile does _not_ take ownership of the file if the
+ call fails; the calling applicaiton is responsible for closing the file
+ if this call returns an error. */
+
+int ov_test_callbacks(void *f,OggVorbis_File *vf,
+ const char *initial,long ibytes,ov_callbacks callbacks)
+{
+ return _ov_open1(f,vf,initial,ibytes,callbacks);
+}
+
+int ov_test(FILE *f,OggVorbis_File *vf,const char *initial,long ibytes){
+ ov_callbacks callbacks = {
+ (size_t (*)(void *, size_t, size_t, void *)) fread,
+ (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap,
+ (int (*)(void *)) fclose,
+ (long (*)(void *)) ftell
+ };
+
+ return ov_test_callbacks((void *)f, vf, initial, ibytes, callbacks);
+}
+
+int ov_test_open(OggVorbis_File *vf){
+ if(vf->ready_state!=PARTOPEN)return(OV_EINVAL);
+ return _ov_open2(vf);
+}
+
+/* How many logical bitstreams in this physical bitstream? */
+long ov_streams(OggVorbis_File *vf){
+ return vf->links;
+}
+
+/* Is the FILE * associated with vf seekable? */
+long ov_seekable(OggVorbis_File *vf){
+ return vf->seekable;
+}
+
+/* returns the bitrate for a given logical bitstream or the entire
+ physical bitstream. If the file is open for random access, it will
+ find the *actual* average bitrate. If the file is streaming, it
+ returns the nominal bitrate (if set) else the average of the
+ upper/lower bounds (if set) else -1 (unset).
+
+ If you want the actual bitrate field settings, get them from the
+ vorbis_info structs */
+
+long ov_bitrate(OggVorbis_File *vf,int i){
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(i>=vf->links)return(OV_EINVAL);
+ if(!vf->seekable && i!=0)return(ov_bitrate(vf,0));
+ if(i<0){
+ ogg_int64_t bits=0;
+ int i;
+ float br;
+ for(i=0;i<vf->links;i++)
+ bits+=(vf->offsets[i+1]-vf->dataoffsets[i])*8;
+ /* This once read: return(rint(bits/ov_time_total(vf,-1)));
+ * gcc 3.x on x86 miscompiled this at optimisation level 2 and above,
+ * so this is slightly transformed to make it work.
+ */
+ br = bits/ov_time_total(vf,-1);
+ return(rint(br));
+ }else{
+ if(vf->seekable){
+ /* return the actual bitrate */
+ return(rint((vf->offsets[i+1]-vf->dataoffsets[i])*8/ov_time_total(vf,i)));
+ }else{
+ /* return nominal if set */
+ if(vf->vi[i].bitrate_nominal>0){
+ return vf->vi[i].bitrate_nominal;
+ }else{
+ if(vf->vi[i].bitrate_upper>0){
+ if(vf->vi[i].bitrate_lower>0){
+ return (vf->vi[i].bitrate_upper+vf->vi[i].bitrate_lower)/2;
+ }else{
+ return vf->vi[i].bitrate_upper;
+ }
+ }
+ return(OV_FALSE);
+ }
+ }
+ }
+}
+
+/* returns the actual bitrate since last call. returns -1 if no
+ additional data to offer since last call (or at beginning of stream),
+ EINVAL if stream is only partially open
+*/
+long ov_bitrate_instant(OggVorbis_File *vf){
+ int link=(vf->seekable?vf->current_link:0);
+ long ret;
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(vf->samptrack==0)return(OV_FALSE);
+ ret=vf->bittrack/vf->samptrack*vf->vi[link].rate+.5;
+ vf->bittrack=0.f;
+ vf->samptrack=0.f;
+ return(ret);
+}
+
+/* Guess */
+long ov_serialnumber(OggVorbis_File *vf,int i){
+ if(i>=vf->links)return(ov_serialnumber(vf,vf->links-1));
+ if(!vf->seekable && i>=0)return(ov_serialnumber(vf,-1));
+ if(i<0){
+ return(vf->current_serialno);
+ }else{
+ return(vf->serialnos[i]);
+ }
+}
+
+/* returns: total raw (compressed) length of content if i==-1
+ raw (compressed) length of that logical bitstream for i==0 to n
+ OV_EINVAL if the stream is not seekable (we can't know the length)
+ or if stream is only partially open
+*/
+ogg_int64_t ov_raw_total(OggVorbis_File *vf,int i){
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(!vf->seekable || i>=vf->links)return(OV_EINVAL);
+ if(i<0){
+ ogg_int64_t acc=0;
+ int i;
+ for(i=0;i<vf->links;i++)
+ acc+=ov_raw_total(vf,i);
+ return(acc);
+ }else{
+ return(vf->offsets[i+1]-vf->offsets[i]);
+ }
+}
+
+/* returns: total PCM length (samples) of content if i==-1 PCM length
+ (samples) of that logical bitstream for i==0 to n
+ OV_EINVAL if the stream is not seekable (we can't know the
+ length) or only partially open
+*/
+ogg_int64_t ov_pcm_total(OggVorbis_File *vf,int i){
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(!vf->seekable || i>=vf->links)return(OV_EINVAL);
+ if(i<0){
+ ogg_int64_t acc=0;
+ int i;
+ for(i=0;i<vf->links;i++)
+ acc+=ov_pcm_total(vf,i);
+ return(acc);
+ }else{
+ return(vf->pcmlengths[i*2+1]);
+ }
+}
+
+/* returns: total seconds of content if i==-1
+ seconds in that logical bitstream for i==0 to n
+ OV_EINVAL if the stream is not seekable (we can't know the
+ length) or only partially open
+*/
+double ov_time_total(OggVorbis_File *vf,int i){
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(!vf->seekable || i>=vf->links)return(OV_EINVAL);
+ if(i<0){
+ double acc=0;
+ int i;
+ for(i=0;i<vf->links;i++)
+ acc+=ov_time_total(vf,i);
+ return(acc);
+ }else{
+ return((double)(vf->pcmlengths[i*2+1])/vf->vi[i].rate);
+ }
+}
+
+/* seek to an offset relative to the *compressed* data. This also
+ scans packets to update the PCM cursor. It will cross a logical
+ bitstream boundary, but only if it can't get any packets out of the
+ tail of the bitstream we seek to (so no surprises).
+
+ returns zero on success, nonzero on failure */
+
+int ov_raw_seek(OggVorbis_File *vf,ogg_int64_t pos){
+ ogg_stream_state work_os;
+ int ret;
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(!vf->seekable)
+ return(OV_ENOSEEK); /* don't dump machine if we can't seek */
+
+ if(pos<0 || pos>vf->end)return(OV_EINVAL);
+
+ /* is the seek position outside our current link [if any]? */
+ if(vf->ready_state>=STREAMSET){
+ if(pos<vf->offsets[vf->current_link] || pos>=vf->offsets[vf->current_link+1])
+ _decode_clear(vf); /* clear out stream state */
+ }
+
+ /* don't yet clear out decoding machine (if it's initialized), in
+ the case we're in the same link. Restart the decode lapping, and
+ let _fetch_and_process_packet deal with a potential bitstream
+ boundary */
+ vf->pcm_offset=-1;
+ ogg_stream_reset_serialno(&vf->os,
+ vf->current_serialno); /* must set serialno */
+ vorbis_synthesis_restart(&vf->vd);
+
+ ret=_seek_helper(vf,pos);
+ if(ret)goto seek_error;
+
+ /* we need to make sure the pcm_offset is set, but we don't want to
+ advance the raw cursor past good packets just to get to the first
+ with a granulepos. That's not equivalent behavior to beginning
+ decoding as immediately after the seek position as possible.
+
+ So, a hack. We use two stream states; a local scratch state and
+ the shared vf->os stream state. We use the local state to
+ scan, and the shared state as a buffer for later decode.
+
+ Unfortuantely, on the last page we still advance to last packet
+ because the granulepos on the last page is not necessarily on a
+ packet boundary, and we need to make sure the granpos is
+ correct.
+ */
+
+ {
+ ogg_page og;
+ ogg_packet op;
+ int lastblock=0;
+ int accblock=0;
+ int thisblock=0;
+ int lastflag=0;
+ int firstflag=0;
+ ogg_int64_t pagepos=-1;
+
+ ogg_stream_init(&work_os,vf->current_serialno); /* get the memory ready */
+ ogg_stream_reset(&work_os); /* eliminate the spurious OV_HOLE
+ return from not necessarily
+ starting from the beginning */
+
+ while(1){
+ if(vf->ready_state>=STREAMSET){
+ /* snarf/scan a packet if we can */
+ int result=ogg_stream_packetout(&work_os,&op);
+
+ if(result>0){
+
+ if(vf->vi[vf->current_link].codec_setup){
+ thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op);
+ if(thisblock<0){
+ ogg_stream_packetout(&vf->os,NULL);
+ thisblock=0;
+ }else{
+
+ /* We can't get a guaranteed correct pcm position out of the
+ last page in a stream because it might have a 'short'
+ granpos, which can only be detected in the presence of a
+ preceding page. However, if the last page is also the first
+ page, the granpos rules of a first page take precedence. Not
+ only that, but for first==last, the EOS page must be treated
+ as if its a normal first page for the stream to open/play. */
+ if(lastflag && !firstflag)
+ ogg_stream_packetout(&vf->os,NULL);
+ else
+ if(lastblock)accblock+=(lastblock+thisblock)>>2;
+ }
+
+ if(op.granulepos!=-1){
+ int i,link=vf->current_link;
+ ogg_int64_t granulepos=op.granulepos-vf->pcmlengths[link*2];
+ if(granulepos<0)granulepos=0;
+
+ for(i=0;i<link;i++)
+ granulepos+=vf->pcmlengths[i*2+1];
+ vf->pcm_offset=granulepos-accblock;
+ if(vf->pcm_offset<0)vf->pcm_offset=0;
+ break;
+ }
+ lastblock=thisblock;
+ continue;
+ }else
+ ogg_stream_packetout(&vf->os,NULL);
+ }
+ }
+
+ if(!lastblock){
+ pagepos=_get_next_page(vf,&og,-1);
+ if(pagepos<0){
+ vf->pcm_offset=ov_pcm_total(vf,-1);
+ break;
+ }
+ }else{
+ /* huh? Bogus stream with packets but no granulepos */
+ vf->pcm_offset=-1;
+ break;
+ }
+
+ /* has our decoding just traversed a bitstream boundary? */
+ if(vf->ready_state>=STREAMSET){
+ if(vf->current_serialno!=ogg_page_serialno(&og)){
+
+ /* two possibilities:
+ 1) our decoding just traversed a bitstream boundary
+ 2) another stream is multiplexed into this logical section? */
+
+ if(ogg_page_bos(&og)){
+ /* we traversed */
+ _decode_clear(vf); /* clear out stream state */
+ ogg_stream_clear(&work_os);
+ } /* else, do nothing; next loop will scoop another page */
+ }
+ }
+
+ if(vf->ready_state<STREAMSET){
+ int link;
+ long serialno = ogg_page_serialno(&og);
+
+ for(link=0;link<vf->links;link++)
+ if(vf->serialnos[link]==serialno)break;
+
+ if(link==vf->links) continue; /* not the desired Vorbis
+ bitstream section; keep
+ trying */
+ vf->current_link=link;
+ vf->current_serialno=serialno;
+ ogg_stream_reset_serialno(&vf->os,serialno);
+ ogg_stream_reset_serialno(&work_os,serialno);
+ vf->ready_state=STREAMSET;
+ firstflag=(pagepos<=vf->dataoffsets[link]);
+ }
+
+ ogg_stream_pagein(&vf->os,&og);
+ ogg_stream_pagein(&work_os,&og);
+ lastflag=ogg_page_eos(&og);
+
+ }
+ }
+
+ ogg_stream_clear(&work_os);
+ vf->bittrack=0.f;
+ vf->samptrack=0.f;
+ return(0);
+
+ seek_error:
+ /* dump the machine so we're in a known state */
+ vf->pcm_offset=-1;
+ ogg_stream_clear(&work_os);
+ _decode_clear(vf);
+ return OV_EBADLINK;
+}
+
+/* Page granularity seek (faster than sample granularity because we
+ don't do the last bit of decode to find a specific sample).
+
+ Seek to the last [granule marked] page preceding the specified pos
+ location, such that decoding past the returned point will quickly
+ arrive at the requested position. */
+int ov_pcm_seek_page(OggVorbis_File *vf,ogg_int64_t pos){
+ int link=-1;
+ ogg_int64_t result=0;
+ ogg_int64_t total=ov_pcm_total(vf,-1);
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(!vf->seekable)return(OV_ENOSEEK);
+
+ if(pos<0 || pos>total)return(OV_EINVAL);
+
+ /* which bitstream section does this pcm offset occur in? */
+ for(link=vf->links-1;link>=0;link--){
+ total-=vf->pcmlengths[link*2+1];
+ if(pos>=total)break;
+ }
+
+ /* Search within the logical bitstream for the page with the highest
+ pcm_pos preceding pos. If we're looking for a position on the
+ first page, bisection will halt without finding our position as
+ it's before the first explicit granulepos fencepost. That case is
+ handled separately below.
+
+ There is a danger here; missing pages or incorrect frame number
+ information in the bitstream could make our task impossible.
+ Account for that (it would be an error condition) */
+
+ /* new search algorithm originally by HB (Nicholas Vinen) */
+
+ {
+ ogg_int64_t end=vf->offsets[link+1];
+ ogg_int64_t begin=vf->dataoffsets[link];
+ ogg_int64_t begintime = vf->pcmlengths[link*2];
+ ogg_int64_t endtime = vf->pcmlengths[link*2+1]+begintime;
+ ogg_int64_t target=pos-total+begintime;
+ ogg_int64_t best=-1;
+ int got_page=0;
+
+ ogg_page og;
+
+ /* if we have only one page, there will be no bisection. Grab the page here */
+ if(begin==end){
+ result=_seek_helper(vf,begin);
+ if(result) goto seek_error;
+
+ result=_get_next_page(vf,&og,1);
+ if(result<0) goto seek_error;
+
+ got_page=1;
+ }
+
+ /* bisection loop */
+ while(begin<end){
+ ogg_int64_t bisect;
+
+ if(end-begin<CHUNKSIZE){
+ bisect=begin;
+ }else{
+ /* take a (pretty decent) guess. */
+ bisect=begin +
+ (ogg_int64_t)((double)(target-begintime)*(end-begin)/(endtime-begintime))
+ - CHUNKSIZE;
+ if(bisect<begin+CHUNKSIZE)
+ bisect=begin;
+ }
+
+ result=_seek_helper(vf,bisect);
+ if(result) goto seek_error;
+
+ /* read loop within the bisection loop */
+ while(begin<end){
+ result=_get_next_page(vf,&og,end-vf->offset);
+ if(result==OV_EREAD) goto seek_error;
+ if(result<0){
+ /* there is no next page! */
+ if(bisect<=begin+1)
+ /* No bisection left to perform. We've either found the
+ best candidate already or failed. Exit loop. */
+ end=begin;
+ else{
+ /* We tried to load a fraction of the last page; back up a
+ bit and try to get the whole last page */
+ if(bisect==0) goto seek_error;
+ bisect-=CHUNKSIZE;
+
+ /* don't repeat/loop on a read we've already performed */
+ if(bisect<=begin)bisect=begin+1;
+
+ /* seek and cntinue bisection */
+ result=_seek_helper(vf,bisect);
+ if(result) goto seek_error;
+ }
+ }else{
+ ogg_int64_t granulepos;
+ got_page=1;
+
+ /* got a page. analyze it */
+ /* only consider pages from primary vorbis stream */
+ if(ogg_page_serialno(&og)!=vf->serialnos[link])
+ continue;
+
+ /* only consider pages with the granulepos set */
+ granulepos=ogg_page_granulepos(&og);
+ if(granulepos==-1)continue;
+
+ if(granulepos<target){
+ /* this page is a successful candidate! Set state */
+
+ best=result; /* raw offset of packet with granulepos */
+ begin=vf->offset; /* raw offset of next page */
+ begintime=granulepos;
+
+ /* if we're before our target but within a short distance,
+ don't bisect; read forward */
+ if(target-begintime>44100)break;
+
+ bisect=begin; /* *not* begin + 1 as above */
+ }else{
+
+ /* This is one of our pages, but the granpos is
+ post-target; it is not a bisection return
+ candidate. (The only way we'd use it is if it's the
+ first page in the stream; we handle that case later
+ outside the bisection) */
+ if(bisect<=begin+1){
+ /* No bisection left to perform. We've either found the
+ best candidate already or failed. Exit loop. */
+ end=begin;
+ }else{
+ if(end==vf->offset){
+ /* bisection read to the end; use the known page
+ boundary (result) to update bisection, back up a
+ little bit, and try again */
+ end=result;
+ bisect-=CHUNKSIZE;
+ if(bisect<=begin)bisect=begin+1;
+ result=_seek_helper(vf,bisect);
+ if(result) goto seek_error;
+ }else{
+ /* Normal bisection */
+ end=bisect;
+ endtime=granulepos;
+ break;
+ }
+ }
+ }
+ }
+ }
+ }
+
+ /* Out of bisection: did it 'fail?' */
+ if(best == -1){
+
+ /* Check the 'looking for data in first page' special case;
+ bisection would 'fail' because our search target was before the
+ first PCM granule position fencepost. */
+
+ if(got_page &&
+ begin == vf->dataoffsets[link] &&
+ ogg_page_serialno(&og)==vf->serialnos[link]){
+
+ /* Yes, this is the beginning-of-stream case. We already have
+ our page, right at the beginning of PCM data. Set state
+ and return. */
+
+ vf->pcm_offset=total;
+
+ if(link!=vf->current_link){
+ /* Different link; dump entire decode machine */
+ _decode_clear(vf);
+
+ vf->current_link=link;
+ vf->current_serialno=vf->serialnos[link];
+ vf->ready_state=STREAMSET;
+
+ }else{
+ vorbis_synthesis_restart(&vf->vd);
+ }
+
+ ogg_stream_reset_serialno(&vf->os,vf->current_serialno);
+ ogg_stream_pagein(&vf->os,&og);
+
+ }else
+ goto seek_error;
+
+ }else{
+
+ /* Bisection found our page. seek to it, update pcm offset. Easier case than
+ raw_seek, don't keep packets preceding granulepos. */
+
+ ogg_page og;
+ ogg_packet op;
+
+ /* seek */
+ result=_seek_helper(vf,best);
+ vf->pcm_offset=-1;
+ if(result) goto seek_error;
+ result=_get_next_page(vf,&og,-1);
+ if(result<0) goto seek_error;
+
+ if(link!=vf->current_link){
+ /* Different link; dump entire decode machine */
+ _decode_clear(vf);
+
+ vf->current_link=link;
+ vf->current_serialno=vf->serialnos[link];
+ vf->ready_state=STREAMSET;
+
+ }else{
+ vorbis_synthesis_restart(&vf->vd);
+ }
+
+ ogg_stream_reset_serialno(&vf->os,vf->current_serialno);
+ ogg_stream_pagein(&vf->os,&og);
+
+ /* pull out all but last packet; the one with granulepos */
+ while(1){
+ result=ogg_stream_packetpeek(&vf->os,&op);
+ if(result==0){
+ /* No packet returned; we exited the bisection with 'best'
+ pointing to a page with a granule position, so the packet
+ finishing this page ('best') originated on a preceding
+ page. Keep fetching previous pages until we get one with
+ a granulepos or without the 'continued' flag set. Then
+ just use raw_seek for simplicity. */
+ /* Do not rewind past the beginning of link data; if we do,
+ it's either a bug or a broken stream */
+ result=best;
+ while(result>vf->dataoffsets[link]){
+ result=_get_prev_page(vf,result,&og);
+ if(result<0) goto seek_error;
+ if(ogg_page_serialno(&og)==vf->current_serialno &&
+ (ogg_page_granulepos(&og)>-1 ||
+ !ogg_page_continued(&og))){
+ return ov_raw_seek(vf,result);
+ }
+ }
+ }
+ if(result<0){
+ result = OV_EBADPACKET;
+ goto seek_error;
+ }
+ if(op.granulepos!=-1){
+ vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2];
+ if(vf->pcm_offset<0)vf->pcm_offset=0;
+ vf->pcm_offset+=total;
+ break;
+ }else
+ result=ogg_stream_packetout(&vf->os,NULL);
+ }
+ }
+ }
+
+ /* verify result */
+ if(vf->pcm_offset>pos || pos>ov_pcm_total(vf,-1)){
+ result=OV_EFAULT;
+ goto seek_error;
+ }
+ vf->bittrack=0.f;
+ vf->samptrack=0.f;
+ return(0);
+
+ seek_error:
+ /* dump machine so we're in a known state */
+ vf->pcm_offset=-1;
+ _decode_clear(vf);
+ return (int)result;
+}
+
+/* seek to a sample offset relative to the decompressed pcm stream
+ returns zero on success, nonzero on failure */
+
+int ov_pcm_seek(OggVorbis_File *vf,ogg_int64_t pos){
+ int thisblock,lastblock=0;
+ int ret=ov_pcm_seek_page(vf,pos);
+ if(ret<0)return(ret);
+ if((ret=_make_decode_ready(vf)))return ret;
+
+ /* discard leading packets we don't need for the lapping of the
+ position we want; don't decode them */
+
+ while(1){
+ ogg_packet op;
+ ogg_page og;
+
+ int ret=ogg_stream_packetpeek(&vf->os,&op);
+ if(ret>0){
+ thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op);
+ if(thisblock<0){
+ ogg_stream_packetout(&vf->os,NULL);
+ continue; /* non audio packet */
+ }
+ if(lastblock)vf->pcm_offset+=(lastblock+thisblock)>>2;
+
+ if(vf->pcm_offset+((thisblock+
+ vorbis_info_blocksize(vf->vi,1))>>2)>=pos)break;
+
+ /* remove the packet from packet queue and track its granulepos */
+ ogg_stream_packetout(&vf->os,NULL);
+ vorbis_synthesis_trackonly(&vf->vb,&op); /* set up a vb with
+ only tracking, no
+ pcm_decode */
+ vorbis_synthesis_blockin(&vf->vd,&vf->vb);
+
+ /* end of logical stream case is hard, especially with exact
+ length positioning. */
+
+ if(op.granulepos>-1){
+ int i;
+ /* always believe the stream markers */
+ vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2];
+ if(vf->pcm_offset<0)vf->pcm_offset=0;
+ for(i=0;i<vf->current_link;i++)
+ vf->pcm_offset+=vf->pcmlengths[i*2+1];
+ }
+
+ lastblock=thisblock;
+
+ }else{
+ if(ret<0 && ret!=OV_HOLE)break;
+
+ /* suck in a new page */
+ if(_get_next_page(vf,&og,-1)<0)break;
+ if(ogg_page_bos(&og))_decode_clear(vf);
+
+ if(vf->ready_state<STREAMSET){
+ long serialno=ogg_page_serialno(&og);
+ int link;
+
+ for(link=0;link<vf->links;link++)
+ if(vf->serialnos[link]==serialno)break;
+ if(link==vf->links) continue;
+ vf->current_link=link;
+
+ vf->ready_state=STREAMSET;
+ vf->current_serialno=ogg_page_serialno(&og);
+ ogg_stream_reset_serialno(&vf->os,serialno);
+ ret=_make_decode_ready(vf);
+ if(ret)return ret;
+ lastblock=0;
+ }
+
+ ogg_stream_pagein(&vf->os,&og);
+ }
+ }
+
+ vf->bittrack=0.f;
+ vf->samptrack=0.f;
+ /* discard samples until we reach the desired position. Crossing a
+ logical bitstream boundary with abandon is OK. */
+ {
+ /* note that halfrate could be set differently in each link, but
+ vorbisfile encoforces all links are set or unset */
+ int hs=vorbis_synthesis_halfrate_p(vf->vi);
+ while(vf->pcm_offset<((pos>>hs)<<hs)){
+ ogg_int64_t target=(pos-vf->pcm_offset)>>hs;
+ long samples=vorbis_synthesis_pcmout(&vf->vd,NULL);
+
+ if(samples>target)samples=target;
+ vorbis_synthesis_read(&vf->vd,samples);
+ vf->pcm_offset+=samples<<hs;
+
+ if(samples<target)
+ if(_fetch_and_process_packet(vf,NULL,1,1)<=0)
+ vf->pcm_offset=ov_pcm_total(vf,-1); /* eof */
+ }
+ }
+ return 0;
+}
+
+/* seek to a playback time relative to the decompressed pcm stream
+ returns zero on success, nonzero on failure */
+int ov_time_seek(OggVorbis_File *vf,double seconds){
+ /* translate time to PCM position and call ov_pcm_seek */
+
+ int link=-1;
+ ogg_int64_t pcm_total=0;
+ double time_total=0.;
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(!vf->seekable)return(OV_ENOSEEK);
+ if(seconds<0)return(OV_EINVAL);
+
+ /* which bitstream section does this time offset occur in? */
+ for(link=0;link<vf->links;link++){
+ double addsec = ov_time_total(vf,link);
+ if(seconds<time_total+addsec)break;
+ time_total+=addsec;
+ pcm_total+=vf->pcmlengths[link*2+1];
+ }
+
+ if(link==vf->links)return(OV_EINVAL);
+
+ /* enough information to convert time offset to pcm offset */
+ {
+ ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate;
+ return(ov_pcm_seek(vf,target));
+ }
+}
+
+/* page-granularity version of ov_time_seek
+ returns zero on success, nonzero on failure */
+int ov_time_seek_page(OggVorbis_File *vf,double seconds){
+ /* translate time to PCM position and call ov_pcm_seek */
+
+ int link=-1;
+ ogg_int64_t pcm_total=0;
+ double time_total=0.;
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(!vf->seekable)return(OV_ENOSEEK);
+ if(seconds<0)return(OV_EINVAL);
+
+ /* which bitstream section does this time offset occur in? */
+ for(link=0;link<vf->links;link++){
+ double addsec = ov_time_total(vf,link);
+ if(seconds<time_total+addsec)break;
+ time_total+=addsec;
+ pcm_total+=vf->pcmlengths[link*2+1];
+ }
+
+ if(link==vf->links)return(OV_EINVAL);
+
+ /* enough information to convert time offset to pcm offset */
+ {
+ ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate;
+ return(ov_pcm_seek_page(vf,target));
+ }
+}
+
+/* tell the current stream offset cursor. Note that seek followed by
+ tell will likely not give the set offset due to caching */
+ogg_int64_t ov_raw_tell(OggVorbis_File *vf){
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ return(vf->offset);
+}
+
+/* return PCM offset (sample) of next PCM sample to be read */
+ogg_int64_t ov_pcm_tell(OggVorbis_File *vf){
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ return(vf->pcm_offset);
+}
+
+/* return time offset (seconds) of next PCM sample to be read */
+double ov_time_tell(OggVorbis_File *vf){
+ int link=0;
+ ogg_int64_t pcm_total=0;
+ double time_total=0.f;
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ if(vf->seekable){
+ pcm_total=ov_pcm_total(vf,-1);
+ time_total=ov_time_total(vf,-1);
+
+ /* which bitstream section does this time offset occur in? */
+ for(link=vf->links-1;link>=0;link--){
+ pcm_total-=vf->pcmlengths[link*2+1];
+ time_total-=ov_time_total(vf,link);
+ if(vf->pcm_offset>=pcm_total)break;
+ }
+ }
+
+ return((double)time_total+(double)(vf->pcm_offset-pcm_total)/vf->vi[link].rate);
+}
+
+/* link: -1) return the vorbis_info struct for the bitstream section
+ currently being decoded
+ 0-n) to request information for a specific bitstream section
+
+ In the case of a non-seekable bitstream, any call returns the
+ current bitstream. NULL in the case that the machine is not
+ initialized */
+
+vorbis_info *ov_info(OggVorbis_File *vf,int link){
+ if(vf->seekable){
+ if(link<0)
+ if(vf->ready_state>=STREAMSET)
+ return vf->vi+vf->current_link;
+ else
+ return vf->vi;
+ else
+ if(link>=vf->links)
+ return NULL;
+ else
+ return vf->vi+link;
+ }else{
+ return vf->vi;
+ }
+}
+
+/* grr, strong typing, grr, no templates/inheritence, grr */
+vorbis_comment *ov_comment(OggVorbis_File *vf,int link){
+ if(vf->seekable){
+ if(link<0)
+ if(vf->ready_state>=STREAMSET)
+ return vf->vc+vf->current_link;
+ else
+ return vf->vc;
+ else
+ if(link>=vf->links)
+ return NULL;
+ else
+ return vf->vc+link;
+ }else{
+ return vf->vc;
+ }
+}
+
+static int host_is_big_endian() {
+ ogg_int32_t pattern = 0xfeedface; /* deadbeef */
+ unsigned char *bytewise = (unsigned char *)&pattern;
+ if (bytewise[0] == 0xfe) return 1;
+ return 0;
+}
+
+/* up to this point, everything could more or less hide the multiple
+ logical bitstream nature of chaining from the toplevel application
+ if the toplevel application didn't particularly care. However, at
+ the point that we actually read audio back, the multiple-section
+ nature must surface: Multiple bitstream sections do not necessarily
+ have to have the same number of channels or sampling rate.
+
+ ov_read returns the sequential logical bitstream number currently
+ being decoded along with the PCM data in order that the toplevel
+ application can take action on channel/sample rate changes. This
+ number will be incremented even for streamed (non-seekable) streams
+ (for seekable streams, it represents the actual logical bitstream
+ index within the physical bitstream. Note that the accessor
+ functions above are aware of this dichotomy).
+
+ ov_read_filter is exactly the same as ov_read except that it processes
+ the decoded audio data through a filter before packing it into the
+ requested format. This gives greater accuracy than applying a filter
+ after the audio has been converted into integral PCM.
+
+ input values: buffer) a buffer to hold packed PCM data for return
+ length) the byte length requested to be placed into buffer
+ bigendianp) should the data be packed LSB first (0) or
+ MSB first (1)
+ word) word size for output. currently 1 (byte) or
+ 2 (16 bit short)
+
+ return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL)
+ 0) EOF
+ n) number of bytes of PCM actually returned. The
+ below works on a packet-by-packet basis, so the
+ return length is not related to the 'length' passed
+ in, just guaranteed to fit.
+
+ *section) set to the logical bitstream number */
+
+long ov_read_filter(OggVorbis_File *vf,char *buffer,int length,
+ int bigendianp,int word,int sgned,int *bitstream,
+ void (*filter)(float **pcm,long channels,long samples,void *filter_param),void *filter_param){
+ int i,j;
+ int host_endian = host_is_big_endian();
+ int hs;
+
+ float **pcm;
+ long samples;
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+
+ while(1){
+ if(vf->ready_state==INITSET){
+ samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
+ if(samples)break;
+ }
+
+ /* suck in another packet */
+ {
+ int ret=_fetch_and_process_packet(vf,NULL,1,1);
+ if(ret==OV_EOF)
+ return(0);
+ if(ret<=0)
+ return(ret);
+ }
+
+ }
+
+ if(samples>0){
+
+ /* yay! proceed to pack data into the byte buffer */
+
+ long channels=ov_info(vf,-1)->channels;
+ long bytespersample=word * channels;
+ vorbis_fpu_control fpu;
+ if(samples>length/bytespersample)samples=length/bytespersample;
+
+ if(samples <= 0)
+ return OV_EINVAL;
+
+ /* Here. */
+ if(filter)
+ filter(pcm,channels,samples,filter_param);
+
+ /* a tight loop to pack each size */
+ {
+ int val;
+ if(word==1){
+ int off=(sgned?0:128);
+ vorbis_fpu_setround(&fpu);
+ for(j=0;j<samples;j++)
+ for(i=0;i<channels;i++){
+ val=vorbis_ftoi(pcm[i][j]*128.f);
+ if(val>127)val=127;
+ else if(val<-128)val=-128;
+ *buffer++=val+off;
+ }
+ vorbis_fpu_restore(fpu);
+ }else{
+ int off=(sgned?0:32768);
+
+ if(host_endian==bigendianp){
+ if(sgned){
+
+ vorbis_fpu_setround(&fpu);
+ for(i=0;i<channels;i++) { /* It's faster in this order */
+ float *src=pcm[i];
+ short *dest=((short *)buffer)+i;
+ for(j=0;j<samples;j++) {
+ val=vorbis_ftoi(src[j]*32768.f);
+ if(val>32767)val=32767;
+ else if(val<-32768)val=-32768;
+ *dest=val;
+ dest+=channels;
+ }
+ }
+ vorbis_fpu_restore(fpu);
+
+ }else{
+
+ vorbis_fpu_setround(&fpu);
+ for(i=0;i<channels;i++) {
+ float *src=pcm[i];
+ short *dest=((short *)buffer)+i;
+ for(j=0;j<samples;j++) {
+ val=vorbis_ftoi(src[j]*32768.f);
+ if(val>32767)val=32767;
+ else if(val<-32768)val=-32768;
+ *dest=val+off;
+ dest+=channels;
+ }
+ }
+ vorbis_fpu_restore(fpu);
+
+ }
+ }else if(bigendianp){
+
+ vorbis_fpu_setround(&fpu);
+ for(j=0;j<samples;j++)
+ for(i=0;i<channels;i++){
+ val=vorbis_ftoi(pcm[i][j]*32768.f);
+ if(val>32767)val=32767;
+ else if(val<-32768)val=-32768;
+ val+=off;
+ *buffer++=(val>>8);
+ *buffer++=(val&0xff);
+ }
+ vorbis_fpu_restore(fpu);
+
+ }else{
+ int val;
+ vorbis_fpu_setround(&fpu);
+ for(j=0;j<samples;j++)
+ for(i=0;i<channels;i++){
+ val=vorbis_ftoi(pcm[i][j]*32768.f);
+ if(val>32767)val=32767;
+ else if(val<-32768)val=-32768;
+ val+=off;
+ *buffer++=(val&0xff);
+ *buffer++=(val>>8);
+ }
+ vorbis_fpu_restore(fpu);
+
+ }
+ }
+ }
+
+ vorbis_synthesis_read(&vf->vd,samples);
+ hs=vorbis_synthesis_halfrate_p(vf->vi);
+ vf->pcm_offset+=(samples<<hs);
+ if(bitstream)*bitstream=vf->current_link;
+ return(samples*bytespersample);
+ }else{
+ return(samples);
+ }
+}
+
+long ov_read(OggVorbis_File *vf,char *buffer,int length,
+ int bigendianp,int word,int sgned,int *bitstream){
+ return ov_read_filter(vf, buffer, length, bigendianp, word, sgned, bitstream, NULL, NULL);
+}
+
+/* input values: pcm_channels) a float vector per channel of output
+ length) the sample length being read by the app
+
+ return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL)
+ 0) EOF
+ n) number of samples of PCM actually returned. The
+ below works on a packet-by-packet basis, so the
+ return length is not related to the 'length' passed
+ in, just guaranteed to fit.
+
+ *section) set to the logical bitstream number */
+
+
+
+long ov_read_float(OggVorbis_File *vf,float ***pcm_channels,int length,
+ int *bitstream){
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+
+ while(1){
+ if(vf->ready_state==INITSET){
+ float **pcm;
+ long samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
+ if(samples){
+ int hs=vorbis_synthesis_halfrate_p(vf->vi);
+ if(pcm_channels)*pcm_channels=pcm;
+ if(samples>length)samples=length;
+ vorbis_synthesis_read(&vf->vd,samples);
+ vf->pcm_offset+=samples<<hs;
+ if(bitstream)*bitstream=vf->current_link;
+ return samples;
+
+ }
+ }
+
+ /* suck in another packet */
+ {
+ int ret=_fetch_and_process_packet(vf,NULL,1,1);
+ if(ret==OV_EOF)return(0);
+ if(ret<=0)return(ret);
+ }
+
+ }
+}
+
+extern const float *vorbis_window(vorbis_dsp_state *v,int W);
+
+static void _ov_splice(float **pcm,float **lappcm,
+ int n1, int n2,
+ int ch1, int ch2,
+ const float *w1, const float *w2){
+ int i,j;
+ const float *w=w1;
+ int n=n1;
+
+ if(n1>n2){
+ n=n2;
+ w=w2;
+ }
+
+ /* splice */
+ for(j=0;j<ch1 && j<ch2;j++){
+ float *s=lappcm[j];
+ float *d=pcm[j];
+
+ for(i=0;i<n;i++){
+ float wd=w[i]*w[i];
+ float ws=1.-wd;
+ d[i]=d[i]*wd + s[i]*ws;
+ }
+ }
+ /* window from zero */
+ for(;j<ch2;j++){
+ float *d=pcm[j];
+ for(i=0;i<n;i++){
+ float wd=w[i]*w[i];
+ d[i]=d[i]*wd;
+ }
+ }
+
+}
+
+/* make sure vf is INITSET */
+static int _ov_initset(OggVorbis_File *vf){
+ while(1){
+ if(vf->ready_state==INITSET)break;
+ /* suck in another packet */
+ {
+ int ret=_fetch_and_process_packet(vf,NULL,1,0);
+ if(ret<0 && ret!=OV_HOLE)return(ret);
+ }
+ }
+ return 0;
+}
+
+/* make sure vf is INITSET and that we have a primed buffer; if
+ we're crosslapping at a stream section boundary, this also makes
+ sure we're sanity checking against the right stream information */
+static int _ov_initprime(OggVorbis_File *vf){
+ vorbis_dsp_state *vd=&vf->vd;
+ while(1){
+ if(vf->ready_state==INITSET)
+ if(vorbis_synthesis_pcmout(vd,NULL))break;
+
+ /* suck in another packet */
+ {
+ int ret=_fetch_and_process_packet(vf,NULL,1,0);
+ if(ret<0 && ret!=OV_HOLE)return(ret);
+ }
+ }
+ return 0;
+}
+
+/* grab enough data for lapping from vf; this may be in the form of
+ unreturned, already-decoded pcm, remaining PCM we will need to
+ decode, or synthetic postextrapolation from last packets. */
+static void _ov_getlap(OggVorbis_File *vf,vorbis_info *vi,vorbis_dsp_state *vd,
+ float **lappcm,int lapsize){
+ int lapcount=0,i;
+ float **pcm;
+
+ /* try first to decode the lapping data */
+ while(lapcount<lapsize){
+ int samples=vorbis_synthesis_pcmout(vd,&pcm);
+ if(samples){
+ if(samples>lapsize-lapcount)samples=lapsize-lapcount;
+ for(i=0;i<vi->channels;i++)
+ memcpy(lappcm[i]+lapcount,pcm[i],sizeof(**pcm)*samples);
+ lapcount+=samples;
+ vorbis_synthesis_read(vd,samples);
+ }else{
+ /* suck in another packet */
+ int ret=_fetch_and_process_packet(vf,NULL,1,0); /* do *not* span */
+ if(ret==OV_EOF)break;
+ }
+ }
+ if(lapcount<lapsize){
+ /* failed to get lapping data from normal decode; pry it from the
+ postextrapolation buffering, or the second half of the MDCT
+ from the last packet */
+ int samples=vorbis_synthesis_lapout(&vf->vd,&pcm);
+ if(samples==0){
+ for(i=0;i<vi->channels;i++)
+ memset(lappcm[i]+lapcount,0,sizeof(**pcm)*lapsize-lapcount);
+ lapcount=lapsize;
+ }else{
+ if(samples>lapsize-lapcount)samples=lapsize-lapcount;
+ for(i=0;i<vi->channels;i++)
+ memcpy(lappcm[i]+lapcount,pcm[i],sizeof(**pcm)*samples);
+ lapcount+=samples;
+ }
+ }
+}
+
+/* this sets up crosslapping of a sample by using trailing data from
+ sample 1 and lapping it into the windowing buffer of sample 2 */
+int ov_crosslap(OggVorbis_File *vf1, OggVorbis_File *vf2){
+ vorbis_info *vi1,*vi2;
+ float **lappcm;
+ float **pcm;
+ const float *w1,*w2;
+ int n1,n2,i,ret,hs1,hs2;
+
+ if(vf1==vf2)return(0); /* degenerate case */
+ if(vf1->ready_state<OPENED)return(OV_EINVAL);
+ if(vf2->ready_state<OPENED)return(OV_EINVAL);
+
+ /* the relevant overlap buffers must be pre-checked and pre-primed
+ before looking at settings in the event that priming would cross
+ a bitstream boundary. So, do it now */
+
+ ret=_ov_initset(vf1);
+ if(ret)return(ret);
+ ret=_ov_initprime(vf2);
+ if(ret)return(ret);
+
+ vi1=ov_info(vf1,-1);
+ vi2=ov_info(vf2,-1);
+ hs1=ov_halfrate_p(vf1);
+ hs2=ov_halfrate_p(vf2);
+
+ lappcm=alloca(sizeof(*lappcm)*vi1->channels);
+ n1=vorbis_info_blocksize(vi1,0)>>(1+hs1);
+ n2=vorbis_info_blocksize(vi2,0)>>(1+hs2);
+ w1=vorbis_window(&vf1->vd,0);
+ w2=vorbis_window(&vf2->vd,0);
+
+ for(i=0;i<vi1->channels;i++)
+ lappcm[i]=alloca(sizeof(**lappcm)*n1);
+
+ _ov_getlap(vf1,vi1,&vf1->vd,lappcm,n1);
+
+ /* have a lapping buffer from vf1; now to splice it into the lapping
+ buffer of vf2 */
+ /* consolidate and expose the buffer. */
+ vorbis_synthesis_lapout(&vf2->vd,&pcm);
+
+#if 0
+ _analysis_output_always("pcmL",0,pcm[0],n1*2,0,0,0);
+ _analysis_output_always("pcmR",0,pcm[1],n1*2,0,0,0);
+#endif
+
+ /* splice */
+ _ov_splice(pcm,lappcm,n1,n2,vi1->channels,vi2->channels,w1,w2);
+
+ /* done */
+ return(0);
+}
+
+static int _ov_64_seek_lap(OggVorbis_File *vf,ogg_int64_t pos,
+ int (*localseek)(OggVorbis_File *,ogg_int64_t)){
+ vorbis_info *vi;
+ float **lappcm;
+ float **pcm;
+ const float *w1,*w2;
+ int n1,n2,ch1,ch2,hs;
+ int i,ret;
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ ret=_ov_initset(vf);
+ if(ret)return(ret);
+ vi=ov_info(vf,-1);
+ hs=ov_halfrate_p(vf);
+
+ ch1=vi->channels;
+ n1=vorbis_info_blocksize(vi,0)>>(1+hs);
+ w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are
+ persistent; even if the decode state
+ from this link gets dumped, this
+ window array continues to exist */
+
+ lappcm=alloca(sizeof(*lappcm)*ch1);
+ for(i=0;i<ch1;i++)
+ lappcm[i]=alloca(sizeof(**lappcm)*n1);
+ _ov_getlap(vf,vi,&vf->vd,lappcm,n1);
+
+ /* have lapping data; seek and prime the buffer */
+ ret=localseek(vf,pos);
+ if(ret)return ret;
+ ret=_ov_initprime(vf);
+ if(ret)return(ret);
+
+ /* Guard against cross-link changes; they're perfectly legal */
+ vi=ov_info(vf,-1);
+ ch2=vi->channels;
+ n2=vorbis_info_blocksize(vi,0)>>(1+hs);
+ w2=vorbis_window(&vf->vd,0);
+
+ /* consolidate and expose the buffer. */
+ vorbis_synthesis_lapout(&vf->vd,&pcm);
+
+ /* splice */
+ _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2);
+
+ /* done */
+ return(0);
+}
+
+int ov_raw_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){
+ return _ov_64_seek_lap(vf,pos,ov_raw_seek);
+}
+
+int ov_pcm_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){
+ return _ov_64_seek_lap(vf,pos,ov_pcm_seek);
+}
+
+int ov_pcm_seek_page_lap(OggVorbis_File *vf,ogg_int64_t pos){
+ return _ov_64_seek_lap(vf,pos,ov_pcm_seek_page);
+}
+
+static int _ov_d_seek_lap(OggVorbis_File *vf,double pos,
+ int (*localseek)(OggVorbis_File *,double)){
+ vorbis_info *vi;
+ float **lappcm;
+ float **pcm;
+ const float *w1,*w2;
+ int n1,n2,ch1,ch2,hs;
+ int i,ret;
+
+ if(vf->ready_state<OPENED)return(OV_EINVAL);
+ ret=_ov_initset(vf);
+ if(ret)return(ret);
+ vi=ov_info(vf,-1);
+ hs=ov_halfrate_p(vf);
+
+ ch1=vi->channels;
+ n1=vorbis_info_blocksize(vi,0)>>(1+hs);
+ w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are
+ persistent; even if the decode state
+ from this link gets dumped, this
+ window array continues to exist */
+
+ lappcm=alloca(sizeof(*lappcm)*ch1);
+ for(i=0;i<ch1;i++)
+ lappcm[i]=alloca(sizeof(**lappcm)*n1);
+ _ov_getlap(vf,vi,&vf->vd,lappcm,n1);
+
+ /* have lapping data; seek and prime the buffer */
+ ret=localseek(vf,pos);
+ if(ret)return ret;
+ ret=_ov_initprime(vf);
+ if(ret)return(ret);
+
+ /* Guard against cross-link changes; they're perfectly legal */
+ vi=ov_info(vf,-1);
+ ch2=vi->channels;
+ n2=vorbis_info_blocksize(vi,0)>>(1+hs);
+ w2=vorbis_window(&vf->vd,0);
+
+ /* consolidate and expose the buffer. */
+ vorbis_synthesis_lapout(&vf->vd,&pcm);
+
+ /* splice */
+ _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2);
+
+ /* done */
+ return(0);
+}
+
+int ov_time_seek_lap(OggVorbis_File *vf,double pos){
+ return _ov_d_seek_lap(vf,pos,ov_time_seek);
+}
+
+int ov_time_seek_page_lap(OggVorbis_File *vf,double pos){
+ return _ov_d_seek_lap(vf,pos,ov_time_seek_page);
+}