dbf-halloween2015: libs/vorbis/vorbisfile.c annotate

dbf-halloween2015

annotate libs/vorbis/vorbisfile.c @ 1:c3f5c32cb210

barfed all the libraries in the source tree to make porting easier

author	John Tsiombikas <nuclear@member.fsf.org>
date	Sun, 01 Nov 2015 00:36:56 +0200
parents
children

rev	line source
nuclear@1	1 /********************************************************************
nuclear@1	2 * *
nuclear@1	3 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
nuclear@1	4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
nuclear@1	5 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
nuclear@1	6 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
nuclear@1	7 * *
nuclear@1	8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 *
nuclear@1	9 * by the Xiph.Org Foundation http://www.xiph.org/ *
nuclear@1	10 * *
nuclear@1	11 ********************************************************************
nuclear@1	12
nuclear@1	13 function: stdio-based convenience library for opening/seeking/decoding
nuclear@1	14 last mod: $Id: vorbisfile.c 17573 2010-10-27 14:53:59Z xiphmont $
nuclear@1	15
nuclear@1	16 ********************************************************************/
nuclear@1	17
nuclear@1	18 #include <stdlib.h>
nuclear@1	19 #include <stdio.h>
nuclear@1	20 #include <errno.h>
nuclear@1	21 #include <string.h>
nuclear@1	22 #include <math.h>
nuclear@1	23
nuclear@1	24 #include "vorbis/codec.h"
nuclear@1	25
nuclear@1	26 /* we don't need or want the static callback symbols here */
nuclear@1	27 #define OV_EXCLUDE_STATIC_CALLBACKS
nuclear@1	28 #include "vorbis/vorbisfile.h"
nuclear@1	29
nuclear@1	30 #include "os.h"
nuclear@1	31 #include "misc.h"
nuclear@1	32
nuclear@1	33 /* A 'chained bitstream' is a Vorbis bitstream that contains more than
nuclear@1	34 one logical bitstream arranged end to end (the only form of Ogg
nuclear@1	35 multiplexing allowed in a Vorbis bitstream; grouping [parallel
nuclear@1	36 multiplexing] is not allowed in Vorbis) */
nuclear@1	37
nuclear@1	38 /* A Vorbis file can be played beginning to end (streamed) without
nuclear@1	39 worrying ahead of time about chaining (see decoder_example.c). If
nuclear@1	40 we have the whole file, however, and want random access
nuclear@1	41 (seeking/scrubbing) or desire to know the total length/time of a
nuclear@1	42 file, we need to account for the possibility of chaining. */
nuclear@1	43
nuclear@1	44 /* We can handle things a number of ways; we can determine the entire
nuclear@1	45 bitstream structure right off the bat, or find pieces on demand.
nuclear@1	46 This example determines and caches structure for the entire
nuclear@1	47 bitstream, but builds a virtual decoder on the fly when moving
nuclear@1	48 between links in the chain. */
nuclear@1	49
nuclear@1	50 /* There are also different ways to implement seeking. Enough
nuclear@1	51 information exists in an Ogg bitstream to seek to
nuclear@1	52 sample-granularity positions in the output. Or, one can seek by
nuclear@1	53 picking some portion of the stream roughly in the desired area if
nuclear@1	54 we only want coarse navigation through the stream. */
nuclear@1	55
nuclear@1	56 /*************************************************************************
nuclear@1	57 * Many, many internal helpers. The intention is not to be confusing;
nuclear@1	58 * rampant duplication and monolithic function implementation would be
nuclear@1	59 * harder to understand anyway. The high level functions are last. Begin
nuclear@1	60 * grokking near the end of the file */
nuclear@1	61
nuclear@1	62 /* read a little more data from the file/pipe into the ogg_sync framer
nuclear@1	63 */
nuclear@1	64 #define CHUNKSIZE 65536 /* greater-than-page-size granularity seeking */
nuclear@1	65 #define READSIZE 2048 /* a smaller read size is needed for low-rate streaming. */
nuclear@1	66
nuclear@1	67 static long _get_data(OggVorbis_File *vf){
nuclear@1	68 errno=0;
nuclear@1	69 if(!(vf->callbacks.read_func))return(-1);
nuclear@1	70 if(vf->datasource){
nuclear@1	71 char *buffer=ogg_sync_buffer(&vf->oy,READSIZE);
nuclear@1	72 long bytes=(vf->callbacks.read_func)(buffer,1,READSIZE,vf->datasource);
nuclear@1	73 if(bytes>0)ogg_sync_wrote(&vf->oy,bytes);
nuclear@1	74 if(bytes==0 && errno)return(-1);
nuclear@1	75 return(bytes);
nuclear@1	76 }else
nuclear@1	77 return(0);
nuclear@1	78 }
nuclear@1	79
nuclear@1	80 /* save a tiny smidge of verbosity to make the code more readable */
nuclear@1	81 static int _seek_helper(OggVorbis_File *vf,ogg_int64_t offset){
nuclear@1	82 if(vf->datasource){
nuclear@1	83 if(!(vf->callbacks.seek_func)\|\|
nuclear@1	84 (vf->callbacks.seek_func)(vf->datasource, offset, SEEK_SET) == -1)
nuclear@1	85 return OV_EREAD;
nuclear@1	86 vf->offset=offset;
nuclear@1	87 ogg_sync_reset(&vf->oy);
nuclear@1	88 }else{
nuclear@1	89 /* shouldn't happen unless someone writes a broken callback */
nuclear@1	90 return OV_EFAULT;
nuclear@1	91 }
nuclear@1	92 return 0;
nuclear@1	93 }
nuclear@1	94
nuclear@1	95 /* The read/seek functions track absolute position within the stream */
nuclear@1	96
nuclear@1	97 /* from the head of the stream, get the next page. boundary specifies
nuclear@1	98 if the function is allowed to fetch more data from the stream (and
nuclear@1	99 how much) or only use internally buffered data.
nuclear@1	100
nuclear@1	101 boundary: -1) unbounded search
nuclear@1	102 0) read no additional data; use cached only
nuclear@1	103 n) search for a new page beginning for n bytes
nuclear@1	104
nuclear@1	105 return: <0) did not find a page (OV_FALSE, OV_EOF, OV_EREAD)
nuclear@1	106 n) found a page at absolute offset n */
nuclear@1	107
nuclear@1	108 static ogg_int64_t _get_next_page(OggVorbis_File vf,ogg_page og,
nuclear@1	109 ogg_int64_t boundary){
nuclear@1	110 if(boundary>0)boundary+=vf->offset;
nuclear@1	111 while(1){
nuclear@1	112 long more;
nuclear@1	113
nuclear@1	114 if(boundary>0 && vf->offset>=boundary)return(OV_FALSE);
nuclear@1	115 more=ogg_sync_pageseek(&vf->oy,og);
nuclear@1	116
nuclear@1	117 if(more<0){
nuclear@1	118 /* skipped n bytes */
nuclear@1	119 vf->offset-=more;
nuclear@1	120 }else{
nuclear@1	121 if(more==0){
nuclear@1	122 /* send more paramedics */
nuclear@1	123 if(!boundary)return(OV_FALSE);
nuclear@1	124 {
nuclear@1	125 long ret=_get_data(vf);
nuclear@1	126 if(ret==0)return(OV_EOF);
nuclear@1	127 if(ret<0)return(OV_EREAD);
nuclear@1	128 }
nuclear@1	129 }else{
nuclear@1	130 /* got a page. Return the offset at the page beginning,
nuclear@1	131 advance the internal offset past the page end */
nuclear@1	132 ogg_int64_t ret=vf->offset;
nuclear@1	133 vf->offset+=more;
nuclear@1	134 return(ret);
nuclear@1	135
nuclear@1	136 }
nuclear@1	137 }
nuclear@1	138 }
nuclear@1	139 }
nuclear@1	140
nuclear@1	141 /* find the latest page beginning before the current stream cursor
nuclear@1	142 position. Much dirtier than the above as Ogg doesn't have any
nuclear@1	143 backward search linkage. no 'readp' as it will certainly have to
nuclear@1	144 read. */
nuclear@1	145 /* returns offset or OV_EREAD, OV_FAULT */
nuclear@1	146 static ogg_int64_t _get_prev_page(OggVorbis_File vf,ogg_page og){
nuclear@1	147 ogg_int64_t begin=vf->offset;
nuclear@1	148 ogg_int64_t end=begin;
nuclear@1	149 ogg_int64_t ret;
nuclear@1	150 ogg_int64_t offset=-1;
nuclear@1	151
nuclear@1	152 while(offset==-1){
nuclear@1	153 begin-=CHUNKSIZE;
nuclear@1	154 if(begin<0)
nuclear@1	155 begin=0;
nuclear@1	156
nuclear@1	157 ret=_seek_helper(vf,begin);
nuclear@1	158 if(ret)return(ret);
nuclear@1	159
nuclear@1	160 while(vf->offset<end){
nuclear@1	161 memset(og,0,sizeof(*og));
nuclear@1	162 ret=_get_next_page(vf,og,end-vf->offset);
nuclear@1	163 if(ret==OV_EREAD)return(OV_EREAD);
nuclear@1	164 if(ret<0){
nuclear@1	165 break;
nuclear@1	166 }else{
nuclear@1	167 offset=ret;
nuclear@1	168 }
nuclear@1	169 }
nuclear@1	170 }
nuclear@1	171
nuclear@1	172 /* In a fully compliant, non-multiplexed stream, we'll still be
nuclear@1	173 holding the last page. In multiplexed (or noncompliant streams),
nuclear@1	174 we will probably have to re-read the last page we saw */
nuclear@1	175 if(og->header_len==0){
nuclear@1	176 ret=_seek_helper(vf,offset);
nuclear@1	177 if(ret)return(ret);
nuclear@1	178
nuclear@1	179 ret=_get_next_page(vf,og,CHUNKSIZE);
nuclear@1	180 if(ret<0)
nuclear@1	181 /* this shouldn't be possible */
nuclear@1	182 return(OV_EFAULT);
nuclear@1	183 }
nuclear@1	184
nuclear@1	185 return(offset);
nuclear@1	186 }
nuclear@1	187
nuclear@1	188 static void _add_serialno(ogg_page og,long serialno_list, int n){
nuclear@1	189 long s = ogg_page_serialno(og);
nuclear@1	190 (*n)++;
nuclear@1	191
nuclear@1	192 if(*serialno_list){
nuclear@1	193 serialno_list = _ogg_realloc(serialno_list, sizeof(*serialno_list)(*n));
nuclear@1	194 }else{
nuclear@1	195 serialno_list = _ogg_malloc(sizeof(*serialno_list));
nuclear@1	196 }
nuclear@1	197
nuclear@1	198 (serialno_list)[(n)-1] = s;
nuclear@1	199 }
nuclear@1	200
nuclear@1	201 /* returns nonzero if found */
nuclear@1	202 static int _lookup_serialno(long s, long *serialno_list, int n){
nuclear@1	203 if(serialno_list){
nuclear@1	204 while(n--){
nuclear@1	205 if(*serialno_list == s) return 1;
nuclear@1	206 serialno_list++;
nuclear@1	207 }
nuclear@1	208 }
nuclear@1	209 return 0;
nuclear@1	210 }
nuclear@1	211
nuclear@1	212 static int _lookup_page_serialno(ogg_page og, long serialno_list, int n){
nuclear@1	213 long s = ogg_page_serialno(og);
nuclear@1	214 return _lookup_serialno(s,serialno_list,n);
nuclear@1	215 }
nuclear@1	216
nuclear@1	217 /* performs the same search as _get_prev_page, but prefers pages of
nuclear@1	218 the specified serial number. If a page of the specified serialno is
nuclear@1	219 spotted during the seek-back-and-read-forward, it will return the
nuclear@1	220 info of last page of the matching serial number instead of the very
nuclear@1	221 last page. If no page of the specified serialno is seen, it will
nuclear@1	222 return the info of last page and alter serialno. /
nuclear@1	223 static ogg_int64_t _get_prev_page_serial(OggVorbis_File *vf,
nuclear@1	224 long *serial_list, int serial_n,
nuclear@1	225 int serialno, ogg_int64_t granpos){
nuclear@1	226 ogg_page og;
nuclear@1	227 ogg_int64_t begin=vf->offset;
nuclear@1	228 ogg_int64_t end=begin;
nuclear@1	229 ogg_int64_t ret;
nuclear@1	230
nuclear@1	231 ogg_int64_t prefoffset=-1;
nuclear@1	232 ogg_int64_t offset=-1;
nuclear@1	233 ogg_int64_t ret_serialno=-1;
nuclear@1	234 ogg_int64_t ret_gran=-1;
nuclear@1	235
nuclear@1	236 while(offset==-1){
nuclear@1	237 begin-=CHUNKSIZE;
nuclear@1	238 if(begin<0)
nuclear@1	239 begin=0;
nuclear@1	240
nuclear@1	241 ret=_seek_helper(vf,begin);
nuclear@1	242 if(ret)return(ret);
nuclear@1	243
nuclear@1	244 while(vf->offset<end){
nuclear@1	245 ret=_get_next_page(vf,&og,end-vf->offset);
nuclear@1	246 if(ret==OV_EREAD)return(OV_EREAD);
nuclear@1	247 if(ret<0){
nuclear@1	248 break;
nuclear@1	249 }else{
nuclear@1	250 ret_serialno=ogg_page_serialno(&og);
nuclear@1	251 ret_gran=ogg_page_granulepos(&og);
nuclear@1	252 offset=ret;
nuclear@1	253
nuclear@1	254 if(ret_serialno == *serialno){
nuclear@1	255 prefoffset=ret;
nuclear@1	256 *granpos=ret_gran;
nuclear@1	257 }
nuclear@1	258
nuclear@1	259 if(!_lookup_serialno(ret_serialno,serial_list,serial_n)){
nuclear@1	260 /* we fell off the end of the link, which means we seeked
nuclear@1	261 back too far and shouldn't have been looking in that link
nuclear@1	262 to begin with. If we found the preferred serial number,
nuclear@1	263 forget that we saw it. */
nuclear@1	264 prefoffset=-1;
nuclear@1	265 }
nuclear@1	266 }
nuclear@1	267 }
nuclear@1	268 }
nuclear@1	269
nuclear@1	270 /* we're not interested in the page... just the serialno and granpos. */
nuclear@1	271 if(prefoffset>=0)return(prefoffset);
nuclear@1	272
nuclear@1	273 *serialno = ret_serialno;
nuclear@1	274 *granpos = ret_gran;
nuclear@1	275 return(offset);
nuclear@1	276
nuclear@1	277 }
nuclear@1	278
nuclear@1	279 /* uses the local ogg_stream storage in vf; this is important for
nuclear@1	280 non-streaming input sources */
nuclear@1	281 static int _fetch_headers(OggVorbis_File vf,vorbis_info vi,vorbis_comment *vc,
nuclear@1	282 long *serialno_list, int serialno_n,
nuclear@1	283 ogg_page *og_ptr){
nuclear@1	284 ogg_page og;
nuclear@1	285 ogg_packet op;
nuclear@1	286 int i,ret;
nuclear@1	287 int allbos=0;
nuclear@1	288
nuclear@1	289 if(!og_ptr){
nuclear@1	290 ogg_int64_t llret=_get_next_page(vf,&og,CHUNKSIZE);
nuclear@1	291 if(llret==OV_EREAD)return(OV_EREAD);
nuclear@1	292 if(llret<0)return(OV_ENOTVORBIS);
nuclear@1	293 og_ptr=&og;
nuclear@1	294 }
nuclear@1	295
nuclear@1	296 vorbis_info_init(vi);
nuclear@1	297 vorbis_comment_init(vc);
nuclear@1	298 vf->ready_state=OPENED;
nuclear@1	299
nuclear@1	300 /* extract the serialnos of all BOS pages + the first set of vorbis
nuclear@1	301 headers we see in the link */
nuclear@1	302
nuclear@1	303 while(ogg_page_bos(og_ptr)){
nuclear@1	304 if(serialno_list){
nuclear@1	305 if(_lookup_page_serialno(og_ptr,serialno_list,serialno_n)){
nuclear@1	306 /* a dupe serialnumber in an initial header packet set == invalid stream */
nuclear@1	307 if(serialno_list)_ogg_free(serialno_list);
nuclear@1	308 *serialno_list=0;
nuclear@1	309 *serialno_n=0;
nuclear@1	310 ret=OV_EBADHEADER;
nuclear@1	311 goto bail_header;
nuclear@1	312 }
nuclear@1	313
nuclear@1	314 _add_serialno(og_ptr,serialno_list,serialno_n);
nuclear@1	315 }
nuclear@1	316
nuclear@1	317 if(vf->ready_state<STREAMSET){
nuclear@1	318 /* we don't have a vorbis stream in this link yet, so begin
nuclear@1	319 prospective stream setup. We need a stream to get packets */
nuclear@1	320 ogg_stream_reset_serialno(&vf->os,ogg_page_serialno(og_ptr));
nuclear@1	321 ogg_stream_pagein(&vf->os,og_ptr);
nuclear@1	322
nuclear@1	323 if(ogg_stream_packetout(&vf->os,&op) > 0 &&
nuclear@1	324 vorbis_synthesis_idheader(&op)){
nuclear@1	325 /* vorbis header; continue setup */
nuclear@1	326 vf->ready_state=STREAMSET;
nuclear@1	327 if((ret=vorbis_synthesis_headerin(vi,vc,&op))){
nuclear@1	328 ret=OV_EBADHEADER;
nuclear@1	329 goto bail_header;
nuclear@1	330 }
nuclear@1	331 }
nuclear@1	332 }
nuclear@1	333
nuclear@1	334 /* get next page */
nuclear@1	335 {
nuclear@1	336 ogg_int64_t llret=_get_next_page(vf,og_ptr,CHUNKSIZE);
nuclear@1	337 if(llret==OV_EREAD){
nuclear@1	338 ret=OV_EREAD;
nuclear@1	339 goto bail_header;
nuclear@1	340 }
nuclear@1	341 if(llret<0){
nuclear@1	342 ret=OV_ENOTVORBIS;
nuclear@1	343 goto bail_header;
nuclear@1	344 }
nuclear@1	345
nuclear@1	346 /* if this page also belongs to our vorbis stream, submit it and break */
nuclear@1	347 if(vf->ready_state==STREAMSET &&
nuclear@1	348 vf->os.serialno == ogg_page_serialno(og_ptr)){
nuclear@1	349 ogg_stream_pagein(&vf->os,og_ptr);
nuclear@1	350 break;
nuclear@1	351 }
nuclear@1	352 }
nuclear@1	353 }
nuclear@1	354
nuclear@1	355 if(vf->ready_state!=STREAMSET){
nuclear@1	356 ret = OV_ENOTVORBIS;
nuclear@1	357 goto bail_header;
nuclear@1	358 }
nuclear@1	359
nuclear@1	360 while(1){
nuclear@1	361
nuclear@1	362 i=0;
nuclear@1	363 while(i<2){ /* get a page loop */
nuclear@1	364
nuclear@1	365 while(i<2){ /* get a packet loop */
nuclear@1	366
nuclear@1	367 int result=ogg_stream_packetout(&vf->os,&op);
nuclear@1	368 if(result==0)break;
nuclear@1	369 if(result==-1){
nuclear@1	370 ret=OV_EBADHEADER;
nuclear@1	371 goto bail_header;
nuclear@1	372 }
nuclear@1	373
nuclear@1	374 if((ret=vorbis_synthesis_headerin(vi,vc,&op)))
nuclear@1	375 goto bail_header;
nuclear@1	376
nuclear@1	377 i++;
nuclear@1	378 }
nuclear@1	379
nuclear@1	380 while(i<2){
nuclear@1	381 if(_get_next_page(vf,og_ptr,CHUNKSIZE)<0){
nuclear@1	382 ret=OV_EBADHEADER;
nuclear@1	383 goto bail_header;
nuclear@1	384 }
nuclear@1	385
nuclear@1	386 /* if this page belongs to the correct stream, go parse it */
nuclear@1	387 if(vf->os.serialno == ogg_page_serialno(og_ptr)){
nuclear@1	388 ogg_stream_pagein(&vf->os,og_ptr);
nuclear@1	389 break;
nuclear@1	390 }
nuclear@1	391
nuclear@1	392 /* if we never see the final vorbis headers before the link
nuclear@1	393 ends, abort */
nuclear@1	394 if(ogg_page_bos(og_ptr)){
nuclear@1	395 if(allbos){
nuclear@1	396 ret = OV_EBADHEADER;
nuclear@1	397 goto bail_header;
nuclear@1	398 }else
nuclear@1	399 allbos=1;
nuclear@1	400 }
nuclear@1	401
nuclear@1	402 /* otherwise, keep looking */
nuclear@1	403 }
nuclear@1	404 }
nuclear@1	405
nuclear@1	406 return 0;
nuclear@1	407 }
nuclear@1	408
nuclear@1	409 bail_header:
nuclear@1	410 vorbis_info_clear(vi);
nuclear@1	411 vorbis_comment_clear(vc);
nuclear@1	412 vf->ready_state=OPENED;
nuclear@1	413
nuclear@1	414 return ret;
nuclear@1	415 }
nuclear@1	416
nuclear@1	417 /* Starting from current cursor position, get initial PCM offset of
nuclear@1	418 next page. Consumes the page in the process without decoding
nuclear@1	419 audio, however this is only called during stream parsing upon
nuclear@1	420 seekable open. */
nuclear@1	421 static ogg_int64_t _initial_pcmoffset(OggVorbis_File vf, vorbis_info vi){
nuclear@1	422 ogg_page og;
nuclear@1	423 ogg_int64_t accumulated=0;
nuclear@1	424 long lastblock=-1;
nuclear@1	425 int result;
nuclear@1	426 int serialno = vf->os.serialno;
nuclear@1	427
nuclear@1	428 while(1){
nuclear@1	429 ogg_packet op;
nuclear@1	430 if(_get_next_page(vf,&og,-1)<0)
nuclear@1	431 break; /* should not be possible unless the file is truncated/mangled */
nuclear@1	432
nuclear@1	433 if(ogg_page_bos(&og)) break;
nuclear@1	434 if(ogg_page_serialno(&og)!=serialno) continue;
nuclear@1	435
nuclear@1	436 /* count blocksizes of all frames in the page */
nuclear@1	437 ogg_stream_pagein(&vf->os,&og);
nuclear@1	438 while((result=ogg_stream_packetout(&vf->os,&op))){
nuclear@1	439 if(result>0){ /* ignore holes */
nuclear@1	440 long thisblock=vorbis_packet_blocksize(vi,&op);
nuclear@1	441 if(lastblock!=-1)
nuclear@1	442 accumulated+=(lastblock+thisblock)>>2;
nuclear@1	443 lastblock=thisblock;
nuclear@1	444 }
nuclear@1	445 }
nuclear@1	446
nuclear@1	447 if(ogg_page_granulepos(&og)!=-1){
nuclear@1	448 /* pcm offset of last packet on the first audio page */
nuclear@1	449 accumulated= ogg_page_granulepos(&og)-accumulated;
nuclear@1	450 break;
nuclear@1	451 }
nuclear@1	452 }
nuclear@1	453
nuclear@1	454 /* less than zero? Either a corrupt file or a stream with samples
nuclear@1	455 trimmed off the beginning, a normal occurrence; in both cases set
nuclear@1	456 the offset to zero */
nuclear@1	457 if(accumulated<0)accumulated=0;
nuclear@1	458
nuclear@1	459 return accumulated;
nuclear@1	460 }
nuclear@1	461
nuclear@1	462 /* finds each bitstream link one at a time using a bisection search
nuclear@1	463 (has to begin by knowing the offset of the lb's initial page).
nuclear@1	464 Recurses for each link so it can alloc the link storage after
nuclear@1	465 finding them all, then unroll and fill the cache at the same time */
nuclear@1	466 static int _bisect_forward_serialno(OggVorbis_File *vf,
nuclear@1	467 ogg_int64_t begin,
nuclear@1	468 ogg_int64_t searched,
nuclear@1	469 ogg_int64_t end,
nuclear@1	470 ogg_int64_t endgran,
nuclear@1	471 int endserial,
nuclear@1	472 long *currentno_list,
nuclear@1	473 int currentnos,
nuclear@1	474 long m){
nuclear@1	475 ogg_int64_t pcmoffset;
nuclear@1	476 ogg_int64_t dataoffset=searched;
nuclear@1	477 ogg_int64_t endsearched=end;
nuclear@1	478 ogg_int64_t next=end;
nuclear@1	479 ogg_int64_t searchgran=-1;
nuclear@1	480 ogg_page og;
nuclear@1	481 ogg_int64_t ret,last;
nuclear@1	482 int serialno = vf->os.serialno;
nuclear@1	483
nuclear@1	484 /* invariants:
nuclear@1	485 we have the headers and serialnos for the link beginning at 'begin'
nuclear@1	486 we have the offset and granpos of the last page in the file (potentially
nuclear@1	487 not a page we care about)
nuclear@1	488 */
nuclear@1	489
nuclear@1	490 /* Is the last page in our list of current serialnumbers? */
nuclear@1	491 if(_lookup_serialno(endserial,currentno_list,currentnos)){
nuclear@1	492
nuclear@1	493 /* last page is in the starting serialno list, so we've bisected
nuclear@1	494 down to (or just started with) a single link. Now we need to
nuclear@1	495 find the last vorbis page belonging to the first vorbis stream
nuclear@1	496 for this link. */
nuclear@1	497
nuclear@1	498 while(endserial != serialno){
nuclear@1	499 endserial = serialno;
nuclear@1	500 vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&endserial,&endgran);
nuclear@1	501 }
nuclear@1	502
nuclear@1	503 vf->links=m+1;
nuclear@1	504 if(vf->offsets)_ogg_free(vf->offsets);
nuclear@1	505 if(vf->serialnos)_ogg_free(vf->serialnos);
nuclear@1	506 if(vf->dataoffsets)_ogg_free(vf->dataoffsets);
nuclear@1	507
nuclear@1	508 vf->offsets=_ogg_malloc((vf->links+1)sizeof(vf->offsets));
nuclear@1	509 vf->vi=_ogg_realloc(vf->vi,vf->linkssizeof(vf->vi));
nuclear@1	510 vf->vc=_ogg_realloc(vf->vc,vf->linkssizeof(vf->vc));
nuclear@1	511 vf->serialnos=_ogg_malloc(vf->linkssizeof(vf->serialnos));
nuclear@1	512 vf->dataoffsets=_ogg_malloc(vf->linkssizeof(vf->dataoffsets));
nuclear@1	513 vf->pcmlengths=_ogg_malloc(vf->links2sizeof(*vf->pcmlengths));
nuclear@1	514
nuclear@1	515 vf->offsets[m+1]=end;
nuclear@1	516 vf->offsets[m]=begin;
nuclear@1	517 vf->pcmlengths[m*2+1]=(endgran<0?0:endgran);
nuclear@1	518
nuclear@1	519 }else{
nuclear@1	520
nuclear@1	521 long *next_serialno_list=NULL;
nuclear@1	522 int next_serialnos=0;
nuclear@1	523 vorbis_info vi;
nuclear@1	524 vorbis_comment vc;
nuclear@1	525
nuclear@1	526 /* the below guards against garbage seperating the last and
nuclear@1	527 first pages of two links. */
nuclear@1	528 while(searched<endsearched){
nuclear@1	529 ogg_int64_t bisect;
nuclear@1	530
nuclear@1	531 if(endsearched-searched<CHUNKSIZE){
nuclear@1	532 bisect=searched;
nuclear@1	533 }else{
nuclear@1	534 bisect=(searched+endsearched)/2;
nuclear@1	535 }
nuclear@1	536
nuclear@1	537 if(bisect != vf->offset){
nuclear@1	538 ret=_seek_helper(vf,bisect);
nuclear@1	539 if(ret)return(ret);
nuclear@1	540 }
nuclear@1	541
nuclear@1	542 last=_get_next_page(vf,&og,-1);
nuclear@1	543 if(last==OV_EREAD)return(OV_EREAD);
nuclear@1	544 if(last<0 \|\| !_lookup_page_serialno(&og,currentno_list,currentnos)){
nuclear@1	545 endsearched=bisect;
nuclear@1	546 if(last>=0)next=last;
nuclear@1	547 }else{
nuclear@1	548 searched=vf->offset;
nuclear@1	549 }
nuclear@1	550 }
nuclear@1	551
nuclear@1	552 /* Bisection point found */
nuclear@1	553
nuclear@1	554 /* for the time being, fetch end PCM offset the simple way */
nuclear@1	555 {
nuclear@1	556 int testserial = serialno+1;
nuclear@1	557 vf->offset = next;
nuclear@1	558 while(testserial != serialno){
nuclear@1	559 testserial = serialno;
nuclear@1	560 vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&testserial,&searchgran);
nuclear@1	561 }
nuclear@1	562 }
nuclear@1	563
nuclear@1	564 if(vf->offset!=next){
nuclear@1	565 ret=_seek_helper(vf,next);
nuclear@1	566 if(ret)return(ret);
nuclear@1	567 }
nuclear@1	568
nuclear@1	569 ret=_fetch_headers(vf,&vi,&vc,&next_serialno_list,&next_serialnos,NULL);
nuclear@1	570 if(ret)return(ret);
nuclear@1	571 serialno = vf->os.serialno;
nuclear@1	572 dataoffset = vf->offset;
nuclear@1	573
nuclear@1	574 /* this will consume a page, however the next bistection always
nuclear@1	575 starts with a raw seek */
nuclear@1	576 pcmoffset = _initial_pcmoffset(vf,&vi);
nuclear@1	577
nuclear@1	578 ret=_bisect_forward_serialno(vf,next,vf->offset,end,endgran,endserial,
nuclear@1	579 next_serialno_list,next_serialnos,m+1);
nuclear@1	580 if(ret)return(ret);
nuclear@1	581
nuclear@1	582 if(next_serialno_list)_ogg_free(next_serialno_list);
nuclear@1	583
nuclear@1	584 vf->offsets[m+1]=next;
nuclear@1	585 vf->serialnos[m+1]=serialno;
nuclear@1	586 vf->dataoffsets[m+1]=dataoffset;
nuclear@1	587
nuclear@1	588 vf->vi[m+1]=vi;
nuclear@1	589 vf->vc[m+1]=vc;
nuclear@1	590
nuclear@1	591 vf->pcmlengths[m*2+1]=searchgran;
nuclear@1	592 vf->pcmlengths[m*2+2]=pcmoffset;
nuclear@1	593 vf->pcmlengths[m*2+3]-=pcmoffset;
nuclear@1	594 if(vf->pcmlengths[m2+3]<0)vf->pcmlengths[m2+3]=0;
nuclear@1	595 }
nuclear@1	596 return(0);
nuclear@1	597 }
nuclear@1	598
nuclear@1	599 static int _make_decode_ready(OggVorbis_File *vf){
nuclear@1	600 if(vf->ready_state>STREAMSET)return 0;
nuclear@1	601 if(vf->ready_state<STREAMSET)return OV_EFAULT;
nuclear@1	602 if(vf->seekable){
nuclear@1	603 if(vorbis_synthesis_init(&vf->vd,vf->vi+vf->current_link))
nuclear@1	604 return OV_EBADLINK;
nuclear@1	605 }else{
nuclear@1	606 if(vorbis_synthesis_init(&vf->vd,vf->vi))
nuclear@1	607 return OV_EBADLINK;
nuclear@1	608 }
nuclear@1	609 vorbis_block_init(&vf->vd,&vf->vb);
nuclear@1	610 vf->ready_state=INITSET;
nuclear@1	611 vf->bittrack=0.f;
nuclear@1	612 vf->samptrack=0.f;
nuclear@1	613 return 0;
nuclear@1	614 }
nuclear@1	615
nuclear@1	616 static int _open_seekable2(OggVorbis_File *vf){
nuclear@1	617 ogg_int64_t dataoffset=vf->dataoffsets[0],end,endgran=-1;
nuclear@1	618 int endserial=vf->os.serialno;
nuclear@1	619 int serialno=vf->os.serialno;
nuclear@1	620
nuclear@1	621 /* we're partially open and have a first link header state in
nuclear@1	622 storage in vf */
nuclear@1	623
nuclear@1	624 /* fetch initial PCM offset */
nuclear@1	625 ogg_int64_t pcmoffset = _initial_pcmoffset(vf,vf->vi);
nuclear@1	626
nuclear@1	627 /* we can seek, so set out learning all about this file */
nuclear@1	628 if(vf->callbacks.seek_func && vf->callbacks.tell_func){
nuclear@1	629 (vf->callbacks.seek_func)(vf->datasource,0,SEEK_END);
nuclear@1	630 vf->offset=vf->end=(vf->callbacks.tell_func)(vf->datasource);
nuclear@1	631 }else{
nuclear@1	632 vf->offset=vf->end=-1;
nuclear@1	633 }
nuclear@1	634
nuclear@1	635 /* If seek_func is implemented, tell_func must also be implemented */
nuclear@1	636 if(vf->end==-1) return(OV_EINVAL);
nuclear@1	637
nuclear@1	638 /* Get the offset of the last page of the physical bitstream, or, if
nuclear@1	639 we're lucky the last vorbis page of this link as most OggVorbis
nuclear@1	640 files will contain a single logical bitstream */
nuclear@1	641 end=_get_prev_page_serial(vf,vf->serialnos+2,vf->serialnos[1],&endserial,&endgran);
nuclear@1	642 if(end<0)return(end);
nuclear@1	643
nuclear@1	644 /* now determine bitstream structure recursively */
nuclear@1	645 if(_bisect_forward_serialno(vf,0,dataoffset,vf->offset,endgran,endserial,
nuclear@1	646 vf->serialnos+2,vf->serialnos[1],0)<0)return(OV_EREAD);
nuclear@1	647
nuclear@1	648 vf->offsets[0]=0;
nuclear@1	649 vf->serialnos[0]=serialno;
nuclear@1	650 vf->dataoffsets[0]=dataoffset;
nuclear@1	651 vf->pcmlengths[0]=pcmoffset;
nuclear@1	652 vf->pcmlengths[1]-=pcmoffset;
nuclear@1	653 if(vf->pcmlengths[1]<0)vf->pcmlengths[1]=0;
nuclear@1	654
nuclear@1	655 return(ov_raw_seek(vf,dataoffset));
nuclear@1	656 }
nuclear@1	657
nuclear@1	658 /* clear out the current logical bitstream decoder */
nuclear@1	659 static void _decode_clear(OggVorbis_File *vf){
nuclear@1	660 vorbis_dsp_clear(&vf->vd);
nuclear@1	661 vorbis_block_clear(&vf->vb);
nuclear@1	662 vf->ready_state=OPENED;
nuclear@1	663 }
nuclear@1	664
nuclear@1	665 /* fetch and process a packet. Handles the case where we're at a
nuclear@1	666 bitstream boundary and dumps the decoding machine. If the decoding
nuclear@1	667 machine is unloaded, it loads it. It also keeps pcm_offset up to
nuclear@1	668 date (seek and read both use this. seek uses a special hack with
nuclear@1	669 readp).
nuclear@1	670
nuclear@1	671 return: <0) error, OV_HOLE (lost packet) or OV_EOF
nuclear@1	672 0) need more data (only if readp==0)
nuclear@1	673 1) got a packet
nuclear@1	674 */
nuclear@1	675
nuclear@1	676 static int _fetch_and_process_packet(OggVorbis_File *vf,
nuclear@1	677 ogg_packet *op_in,
nuclear@1	678 int readp,
nuclear@1	679 int spanp){
nuclear@1	680 ogg_page og;
nuclear@1	681
nuclear@1	682 /* handle one packet. Try to fetch it from current stream state */
nuclear@1	683 /* extract packets from page */
nuclear@1	684 while(1){
nuclear@1	685
nuclear@1	686 if(vf->ready_state==STREAMSET){
nuclear@1	687 int ret=_make_decode_ready(vf);
nuclear@1	688 if(ret<0)return ret;
nuclear@1	689 }
nuclear@1	690
nuclear@1	691 /* process a packet if we can. */
nuclear@1	692
nuclear@1	693 if(vf->ready_state==INITSET){
nuclear@1	694 int hs=vorbis_synthesis_halfrate_p(vf->vi);
nuclear@1	695
nuclear@1	696 while(1) {
nuclear@1	697 ogg_packet op;
nuclear@1	698 ogg_packet *op_ptr=(op_in?op_in:&op);
nuclear@1	699 int result=ogg_stream_packetout(&vf->os,op_ptr);
nuclear@1	700 ogg_int64_t granulepos;
nuclear@1	701
nuclear@1	702 op_in=NULL;
nuclear@1	703 if(result==-1)return(OV_HOLE); /* hole in the data. */
nuclear@1	704 if(result>0){
nuclear@1	705 /* got a packet. process it */
nuclear@1	706 granulepos=op_ptr->granulepos;
nuclear@1	707 if(!vorbis_synthesis(&vf->vb,op_ptr)){ /* lazy check for lazy
nuclear@1	708 header handling. The
nuclear@1	709 header packets aren't
nuclear@1	710 audio, so if/when we
nuclear@1	711 submit them,
nuclear@1	712 vorbis_synthesis will
nuclear@1	713 reject them */
nuclear@1	714
nuclear@1	715 /* suck in the synthesis data and track bitrate */
nuclear@1	716 {
nuclear@1	717 int oldsamples=vorbis_synthesis_pcmout(&vf->vd,NULL);
nuclear@1	718 /* for proper use of libvorbis within libvorbisfile,
nuclear@1	719 oldsamples will always be zero. */
nuclear@1	720 if(oldsamples)return(OV_EFAULT);
nuclear@1	721
nuclear@1	722 vorbis_synthesis_blockin(&vf->vd,&vf->vb);
nuclear@1	723 vf->samptrack+=(vorbis_synthesis_pcmout(&vf->vd,NULL)<<hs);
nuclear@1	724 vf->bittrack+=op_ptr->bytes*8;
nuclear@1	725 }
nuclear@1	726
nuclear@1	727 /* update the pcm offset. */
nuclear@1	728 if(granulepos!=-1 && !op_ptr->e_o_s){
nuclear@1	729 int link=(vf->seekable?vf->current_link:0);
nuclear@1	730 int i,samples;
nuclear@1	731
nuclear@1	732 /* this packet has a pcm_offset on it (the last packet
nuclear@1	733 completed on a page carries the offset) After processing
nuclear@1	734 (above), we know the pcm position of the last sample
nuclear@1	735 ready to be returned. Find the offset of the first
nuclear@1	736
nuclear@1	737 As an aside, this trick is inaccurate if we begin
nuclear@1	738 reading anew right at the last page; the end-of-stream
nuclear@1	739 granulepos declares the last frame in the stream, and the
nuclear@1	740 last packet of the last page may be a partial frame.
nuclear@1	741 So, we need a previous granulepos from an in-sequence page
nuclear@1	742 to have a reference point. Thus the !op_ptr->e_o_s clause
nuclear@1	743 above */
nuclear@1	744
nuclear@1	745 if(vf->seekable && link>0)
nuclear@1	746 granulepos-=vf->pcmlengths[link*2];
nuclear@1	747 if(granulepos<0)granulepos=0; /* actually, this
nuclear@1	748 shouldn't be possible
nuclear@1	749 here unless the stream
nuclear@1	750 is very broken */
nuclear@1	751
nuclear@1	752 samples=(vorbis_synthesis_pcmout(&vf->vd,NULL)<<hs);
nuclear@1	753
nuclear@1	754 granulepos-=samples;
nuclear@1	755 for(i=0;i<link;i++)
nuclear@1	756 granulepos+=vf->pcmlengths[i*2+1];
nuclear@1	757 vf->pcm_offset=granulepos;
nuclear@1	758 }
nuclear@1	759 return(1);
nuclear@1	760 }
nuclear@1	761 }
nuclear@1	762 else
nuclear@1	763 break;
nuclear@1	764 }
nuclear@1	765 }
nuclear@1	766
nuclear@1	767 if(vf->ready_state>=OPENED){
nuclear@1	768 ogg_int64_t ret;
nuclear@1	769
nuclear@1	770 while(1){
nuclear@1	771 /* the loop is not strictly necessary, but there's no sense in
nuclear@1	772 doing the extra checks of the larger loop for the common
nuclear@1	773 case in a multiplexed bistream where the page is simply
nuclear@1	774 part of a different logical bitstream; keep reading until
nuclear@1	775 we get one with the correct serialno */
nuclear@1	776
nuclear@1	777 if(!readp)return(0);
nuclear@1	778 if((ret=_get_next_page(vf,&og,-1))<0){
nuclear@1	779 return(OV_EOF); /* eof. leave unitialized */
nuclear@1	780 }
nuclear@1	781
nuclear@1	782 /* bitrate tracking; add the header's bytes here, the body bytes
nuclear@1	783 are done by packet above */
nuclear@1	784 vf->bittrack+=og.header_len*8;
nuclear@1	785
nuclear@1	786 if(vf->ready_state==INITSET){
nuclear@1	787 if(vf->current_serialno!=ogg_page_serialno(&og)){
nuclear@1	788
nuclear@1	789 /* two possibilities:
nuclear@1	790 1) our decoding just traversed a bitstream boundary
nuclear@1	791 2) another stream is multiplexed into this logical section */
nuclear@1	792
nuclear@1	793 if(ogg_page_bos(&og)){
nuclear@1	794 /* boundary case */
nuclear@1	795 if(!spanp)
nuclear@1	796 return(OV_EOF);
nuclear@1	797
nuclear@1	798 _decode_clear(vf);
nuclear@1	799
nuclear@1	800 if(!vf->seekable){
nuclear@1	801 vorbis_info_clear(vf->vi);
nuclear@1	802 vorbis_comment_clear(vf->vc);
nuclear@1	803 }
nuclear@1	804 break;
nuclear@1	805
nuclear@1	806 }else
nuclear@1	807 continue; /* possibility #2 */
nuclear@1	808 }
nuclear@1	809 }
nuclear@1	810
nuclear@1	811 break;
nuclear@1	812 }
nuclear@1	813 }
nuclear@1	814
nuclear@1	815 /* Do we need to load a new machine before submitting the page? */
nuclear@1	816 /* This is different in the seekable and non-seekable cases.
nuclear@1	817
nuclear@1	818 In the seekable case, we already have all the header
nuclear@1	819 information loaded and cached; we just initialize the machine
nuclear@1	820 with it and continue on our merry way.
nuclear@1	821
nuclear@1	822 In the non-seekable (streaming) case, we'll only be at a
nuclear@1	823 boundary if we just left the previous logical bitstream and
nuclear@1	824 we're now nominally at the header of the next bitstream
nuclear@1	825 */
nuclear@1	826
nuclear@1	827 if(vf->ready_state!=INITSET){
nuclear@1	828 int link;
nuclear@1	829
nuclear@1	830 if(vf->ready_state<STREAMSET){
nuclear@1	831 if(vf->seekable){
nuclear@1	832 long serialno = ogg_page_serialno(&og);
nuclear@1	833
nuclear@1	834 /* match the serialno to bitstream section. We use this rather than
nuclear@1	835 offset positions to avoid problems near logical bitstream
nuclear@1	836 boundaries */
nuclear@1	837
nuclear@1	838 for(link=0;link<vf->links;link++)
nuclear@1	839 if(vf->serialnos[link]==serialno)break;
nuclear@1	840
nuclear@1	841 if(link==vf->links) continue; /* not the desired Vorbis
nuclear@1	842 bitstream section; keep
nuclear@1	843 trying */
nuclear@1	844
nuclear@1	845 vf->current_serialno=serialno;
nuclear@1	846 vf->current_link=link;
nuclear@1	847
nuclear@1	848 ogg_stream_reset_serialno(&vf->os,vf->current_serialno);
nuclear@1	849 vf->ready_state=STREAMSET;
nuclear@1	850
nuclear@1	851 }else{
nuclear@1	852 /* we're streaming */
nuclear@1	853 /* fetch the three header packets, build the info struct */
nuclear@1	854
nuclear@1	855 int ret=_fetch_headers(vf,vf->vi,vf->vc,NULL,NULL,&og);
nuclear@1	856 if(ret)return(ret);
nuclear@1	857 vf->current_serialno=vf->os.serialno;
nuclear@1	858 vf->current_link++;
nuclear@1	859 link=0;
nuclear@1	860 }
nuclear@1	861 }
nuclear@1	862 }
nuclear@1	863
nuclear@1	864 /* the buffered page is the data we want, and we're ready for it;
nuclear@1	865 add it to the stream state */
nuclear@1	866 ogg_stream_pagein(&vf->os,&og);
nuclear@1	867
nuclear@1	868 }
nuclear@1	869 }
nuclear@1	870
nuclear@1	871 /* if, eg, 64 bit stdio is configured by default, this will build with
nuclear@1	872 fseek64 */
nuclear@1	873 static int _fseek64_wrap(FILE *f,ogg_int64_t off,int whence){
nuclear@1	874 if(f==NULL)return(-1);
nuclear@1	875 return fseek(f,off,whence);
nuclear@1	876 }
nuclear@1	877
nuclear@1	878 static int _ov_open1(void f,OggVorbis_File vf,const char *initial,
nuclear@1	879 long ibytes, ov_callbacks callbacks){
nuclear@1	880 int offsettest=((f && callbacks.seek_func)?callbacks.seek_func(f,0,SEEK_CUR):-1);
nuclear@1	881 long *serialno_list=NULL;
nuclear@1	882 int serialno_list_size=0;
nuclear@1	883 int ret;
nuclear@1	884
nuclear@1	885 memset(vf,0,sizeof(*vf));
nuclear@1	886 vf->datasource=f;
nuclear@1	887 vf->callbacks = callbacks;
nuclear@1	888
nuclear@1	889 /* init the framing state */
nuclear@1	890 ogg_sync_init(&vf->oy);
nuclear@1	891
nuclear@1	892 /* perhaps some data was previously read into a buffer for testing
nuclear@1	893 against other stream types. Allow initialization from this
nuclear@1	894 previously read data (especially as we may be reading from a
nuclear@1	895 non-seekable stream) */
nuclear@1	896 if(initial){
nuclear@1	897 char *buffer=ogg_sync_buffer(&vf->oy,ibytes);
nuclear@1	898 memcpy(buffer,initial,ibytes);
nuclear@1	899 ogg_sync_wrote(&vf->oy,ibytes);
nuclear@1	900 }
nuclear@1	901
nuclear@1	902 /* can we seek? Stevens suggests the seek test was portable */
nuclear@1	903 if(offsettest!=-1)vf->seekable=1;
nuclear@1	904
nuclear@1	905 /* No seeking yet; Set up a 'single' (current) logical bitstream
nuclear@1	906 entry for partial open */
nuclear@1	907 vf->links=1;
nuclear@1	908 vf->vi=_ogg_calloc(vf->links,sizeof(*vf->vi));
nuclear@1	909 vf->vc=_ogg_calloc(vf->links,sizeof(*vf->vc));
nuclear@1	910 ogg_stream_init(&vf->os,-1); /* fill in the serialno later */
nuclear@1	911
nuclear@1	912 /* Fetch all BOS pages, store the vorbis header and all seen serial
nuclear@1	913 numbers, load subsequent vorbis setup headers */
nuclear@1	914 if((ret=_fetch_headers(vf,vf->vi,vf->vc,&serialno_list,&serialno_list_size,NULL))<0){
nuclear@1	915 vf->datasource=NULL;
nuclear@1	916 ov_clear(vf);
nuclear@1	917 }else{
nuclear@1	918 /* serial number list for first link needs to be held somewhere
nuclear@1	919 for second stage of seekable stream open; this saves having to
nuclear@1	920 seek/reread first link's serialnumber data then. */
nuclear@1	921 vf->serialnos=_ogg_calloc(serialno_list_size+2,sizeof(*vf->serialnos));
nuclear@1	922 vf->serialnos[0]=vf->current_serialno=vf->os.serialno;
nuclear@1	923 vf->serialnos[1]=serialno_list_size;
nuclear@1	924 memcpy(vf->serialnos+2,serialno_list,serialno_list_sizesizeof(vf->serialnos));
nuclear@1	925
nuclear@1	926 vf->offsets=_ogg_calloc(1,sizeof(*vf->offsets));
nuclear@1	927 vf->dataoffsets=_ogg_calloc(1,sizeof(*vf->dataoffsets));
nuclear@1	928 vf->offsets[0]=0;
nuclear@1	929 vf->dataoffsets[0]=vf->offset;
nuclear@1	930
nuclear@1	931 vf->ready_state=PARTOPEN;
nuclear@1	932 }
nuclear@1	933 if(serialno_list)_ogg_free(serialno_list);
nuclear@1	934 return(ret);
nuclear@1	935 }
nuclear@1	936
nuclear@1	937 static int _ov_open2(OggVorbis_File *vf){
nuclear@1	938 if(vf->ready_state != PARTOPEN) return OV_EINVAL;
nuclear@1	939 vf->ready_state=OPENED;
nuclear@1	940 if(vf->seekable){
nuclear@1	941 int ret=_open_seekable2(vf);
nuclear@1	942 if(ret){
nuclear@1	943 vf->datasource=NULL;
nuclear@1	944 ov_clear(vf);
nuclear@1	945 }
nuclear@1	946 return(ret);
nuclear@1	947 }else
nuclear@1	948 vf->ready_state=STREAMSET;
nuclear@1	949
nuclear@1	950 return 0;
nuclear@1	951 }
nuclear@1	952
nuclear@1	953
nuclear@1	954 /* clear out the OggVorbis_File struct */
nuclear@1	955 int ov_clear(OggVorbis_File *vf){
nuclear@1	956 if(vf){
nuclear@1	957 vorbis_block_clear(&vf->vb);
nuclear@1	958 vorbis_dsp_clear(&vf->vd);
nuclear@1	959 ogg_stream_clear(&vf->os);
nuclear@1	960
nuclear@1	961 if(vf->vi && vf->links){
nuclear@1	962 int i;
nuclear@1	963 for(i=0;i<vf->links;i++){
nuclear@1	964 vorbis_info_clear(vf->vi+i);
nuclear@1	965 vorbis_comment_clear(vf->vc+i);
nuclear@1	966 }
nuclear@1	967 _ogg_free(vf->vi);
nuclear@1	968 _ogg_free(vf->vc);
nuclear@1	969 }
nuclear@1	970 if(vf->dataoffsets)_ogg_free(vf->dataoffsets);
nuclear@1	971 if(vf->pcmlengths)_ogg_free(vf->pcmlengths);
nuclear@1	972 if(vf->serialnos)_ogg_free(vf->serialnos);
nuclear@1	973 if(vf->offsets)_ogg_free(vf->offsets);
nuclear@1	974 ogg_sync_clear(&vf->oy);
nuclear@1	975 if(vf->datasource && vf->callbacks.close_func)
nuclear@1	976 (vf->callbacks.close_func)(vf->datasource);
nuclear@1	977 memset(vf,0,sizeof(*vf));
nuclear@1	978 }
nuclear@1	979 #ifdef DEBUG_LEAKS
nuclear@1	980 _VDBG_dump();
nuclear@1	981 #endif
nuclear@1	982 return(0);
nuclear@1	983 }
nuclear@1	984
nuclear@1	985 /* inspects the OggVorbis file and finds/documents all the logical
nuclear@1	986 bitstreams contained in it. Tries to be tolerant of logical
nuclear@1	987 bitstream sections that are truncated/woogie.
nuclear@1	988
nuclear@1	989 return: -1) error
nuclear@1	990 0) OK
nuclear@1	991 */
nuclear@1	992
nuclear@1	993 int ov_open_callbacks(void f,OggVorbis_File vf,
nuclear@1	994 const char *initial,long ibytes,ov_callbacks callbacks){
nuclear@1	995 int ret=_ov_open1(f,vf,initial,ibytes,callbacks);
nuclear@1	996 if(ret)return ret;
nuclear@1	997 return _ov_open2(vf);
nuclear@1	998 }
nuclear@1	999
nuclear@1	1000 int ov_open(FILE f,OggVorbis_File vf,const char *initial,long ibytes){
nuclear@1	1001 ov_callbacks callbacks = {
nuclear@1	1002 (size_t ()(void , size_t, size_t, void *)) fread,
nuclear@1	1003 (int ()(void , ogg_int64_t, int)) _fseek64_wrap,
nuclear@1	1004 (int ()(void )) fclose,
nuclear@1	1005 (long ()(void )) ftell
nuclear@1	1006 };
nuclear@1	1007
nuclear@1	1008 return ov_open_callbacks((void *)f, vf, initial, ibytes, callbacks);
nuclear@1	1009 }
nuclear@1	1010
nuclear@1	1011 int ov_fopen(const char path,OggVorbis_File vf){
nuclear@1	1012 int ret;
nuclear@1	1013 FILE *f = fopen(path,"rb");
nuclear@1	1014 if(!f) return -1;
nuclear@1	1015
nuclear@1	1016 ret = ov_open(f,vf,NULL,0);
nuclear@1	1017 if(ret) fclose(f);
nuclear@1	1018 return ret;
nuclear@1	1019 }
nuclear@1	1020
nuclear@1	1021
nuclear@1	1022 /* cheap hack for game usage where downsampling is desirable; there's
nuclear@1	1023 no need for SRC as we can just do it cheaply in libvorbis. */
nuclear@1	1024
nuclear@1	1025 int ov_halfrate(OggVorbis_File *vf,int flag){
nuclear@1	1026 int i;
nuclear@1	1027 if(vf->vi==NULL)return OV_EINVAL;
nuclear@1	1028 if(vf->ready_state>STREAMSET){
nuclear@1	1029 /* clear out stream state; dumping the decode machine is needed to
nuclear@1	1030 reinit the MDCT lookups. */
nuclear@1	1031 vorbis_dsp_clear(&vf->vd);
nuclear@1	1032 vorbis_block_clear(&vf->vb);
nuclear@1	1033 vf->ready_state=STREAMSET;
nuclear@1	1034 if(vf->pcm_offset>=0){
nuclear@1	1035 ogg_int64_t pos=vf->pcm_offset;
nuclear@1	1036 vf->pcm_offset=-1; /* make sure the pos is dumped if unseekable */
nuclear@1	1037 ov_pcm_seek(vf,pos);
nuclear@1	1038 }
nuclear@1	1039 }
nuclear@1	1040
nuclear@1	1041 for(i=0;i<vf->links;i++){
nuclear@1	1042 if(vorbis_synthesis_halfrate(vf->vi+i,flag)){
nuclear@1	1043 if(flag) ov_halfrate(vf,0);
nuclear@1	1044 return OV_EINVAL;
nuclear@1	1045 }
nuclear@1	1046 }
nuclear@1	1047 return 0;
nuclear@1	1048 }
nuclear@1	1049
nuclear@1	1050 int ov_halfrate_p(OggVorbis_File *vf){
nuclear@1	1051 if(vf->vi==NULL)return OV_EINVAL;
nuclear@1	1052 return vorbis_synthesis_halfrate_p(vf->vi);
nuclear@1	1053 }
nuclear@1	1054
nuclear@1	1055 /* Only partially open the vorbis file; test for Vorbisness, and load
nuclear@1	1056 the headers for the first chain. Do not seek (although test for
nuclear@1	1057 seekability). Use ov_test_open to finish opening the file, else
nuclear@1	1058 ov_clear to close/free it. Same return codes as open. */
nuclear@1	1059
nuclear@1	1060 int ov_test_callbacks(void f,OggVorbis_File vf,
nuclear@1	1061 const char *initial,long ibytes,ov_callbacks callbacks)
nuclear@1	1062 {
nuclear@1	1063 return _ov_open1(f,vf,initial,ibytes,callbacks);
nuclear@1	1064 }
nuclear@1	1065
nuclear@1	1066 int ov_test(FILE f,OggVorbis_File vf,const char *initial,long ibytes){
nuclear@1	1067 ov_callbacks callbacks = {
nuclear@1	1068 (size_t ()(void , size_t, size_t, void *)) fread,
nuclear@1	1069 (int ()(void , ogg_int64_t, int)) _fseek64_wrap,
nuclear@1	1070 (int ()(void )) fclose,
nuclear@1	1071 (long ()(void )) ftell
nuclear@1	1072 };
nuclear@1	1073
nuclear@1	1074 return ov_test_callbacks((void *)f, vf, initial, ibytes, callbacks);
nuclear@1	1075 }
nuclear@1	1076
nuclear@1	1077 int ov_test_open(OggVorbis_File *vf){
nuclear@1	1078 if(vf->ready_state!=PARTOPEN)return(OV_EINVAL);
nuclear@1	1079 return _ov_open2(vf);
nuclear@1	1080 }
nuclear@1	1081
nuclear@1	1082 /* How many logical bitstreams in this physical bitstream? */
nuclear@1	1083 long ov_streams(OggVorbis_File *vf){
nuclear@1	1084 return vf->links;
nuclear@1	1085 }
nuclear@1	1086
nuclear@1	1087 /* Is the FILE * associated with vf seekable? */
nuclear@1	1088 long ov_seekable(OggVorbis_File *vf){
nuclear@1	1089 return vf->seekable;
nuclear@1	1090 }
nuclear@1	1091
nuclear@1	1092 /* returns the bitrate for a given logical bitstream or the entire
nuclear@1	1093 physical bitstream. If the file is open for random access, it will
nuclear@1	1094 find the actual average bitrate. If the file is streaming, it
nuclear@1	1095 returns the nominal bitrate (if set) else the average of the
nuclear@1	1096 upper/lower bounds (if set) else -1 (unset).
nuclear@1	1097
nuclear@1	1098 If you want the actual bitrate field settings, get them from the
nuclear@1	1099 vorbis_info structs */
nuclear@1	1100
nuclear@1	1101 long ov_bitrate(OggVorbis_File *vf,int i){
nuclear@1	1102 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1103 if(i>=vf->links)return(OV_EINVAL);
nuclear@1	1104 if(!vf->seekable && i!=0)return(ov_bitrate(vf,0));
nuclear@1	1105 if(i<0){
nuclear@1	1106 ogg_int64_t bits=0;
nuclear@1	1107 int i;
nuclear@1	1108 float br;
nuclear@1	1109 for(i=0;i<vf->links;i++)
nuclear@1	1110 bits+=(vf->offsets[i+1]-vf->dataoffsets[i])*8;
nuclear@1	1111 /* This once read: return(rint(bits/ov_time_total(vf,-1)));
nuclear@1	1112 * gcc 3.x on x86 miscompiled this at optimisation level 2 and above,
nuclear@1	1113 * so this is slightly transformed to make it work.
nuclear@1	1114 */
nuclear@1	1115 br = bits/ov_time_total(vf,-1);
nuclear@1	1116 return(rint(br));
nuclear@1	1117 }else{
nuclear@1	1118 if(vf->seekable){
nuclear@1	1119 /* return the actual bitrate */
nuclear@1	1120 return(rint((vf->offsets[i+1]-vf->dataoffsets[i])*8/ov_time_total(vf,i)));
nuclear@1	1121 }else{
nuclear@1	1122 /* return nominal if set */
nuclear@1	1123 if(vf->vi[i].bitrate_nominal>0){
nuclear@1	1124 return vf->vi[i].bitrate_nominal;
nuclear@1	1125 }else{
nuclear@1	1126 if(vf->vi[i].bitrate_upper>0){
nuclear@1	1127 if(vf->vi[i].bitrate_lower>0){
nuclear@1	1128 return (vf->vi[i].bitrate_upper+vf->vi[i].bitrate_lower)/2;
nuclear@1	1129 }else{
nuclear@1	1130 return vf->vi[i].bitrate_upper;
nuclear@1	1131 }
nuclear@1	1132 }
nuclear@1	1133 return(OV_FALSE);
nuclear@1	1134 }
nuclear@1	1135 }
nuclear@1	1136 }
nuclear@1	1137 }
nuclear@1	1138
nuclear@1	1139 /* returns the actual bitrate since last call. returns -1 if no
nuclear@1	1140 additional data to offer since last call (or at beginning of stream),
nuclear@1	1141 EINVAL if stream is only partially open
nuclear@1	1142 */
nuclear@1	1143 long ov_bitrate_instant(OggVorbis_File *vf){
nuclear@1	1144 int link=(vf->seekable?vf->current_link:0);
nuclear@1	1145 long ret;
nuclear@1	1146 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1147 if(vf->samptrack==0)return(OV_FALSE);
nuclear@1	1148 ret=vf->bittrack/vf->samptrack*vf->vi[link].rate+.5;
nuclear@1	1149 vf->bittrack=0.f;
nuclear@1	1150 vf->samptrack=0.f;
nuclear@1	1151 return(ret);
nuclear@1	1152 }
nuclear@1	1153
nuclear@1	1154 /* Guess */
nuclear@1	1155 long ov_serialnumber(OggVorbis_File *vf,int i){
nuclear@1	1156 if(i>=vf->links)return(ov_serialnumber(vf,vf->links-1));
nuclear@1	1157 if(!vf->seekable && i>=0)return(ov_serialnumber(vf,-1));
nuclear@1	1158 if(i<0){
nuclear@1	1159 return(vf->current_serialno);
nuclear@1	1160 }else{
nuclear@1	1161 return(vf->serialnos[i]);
nuclear@1	1162 }
nuclear@1	1163 }
nuclear@1	1164
nuclear@1	1165 /* returns: total raw (compressed) length of content if i==-1
nuclear@1	1166 raw (compressed) length of that logical bitstream for i==0 to n
nuclear@1	1167 OV_EINVAL if the stream is not seekable (we can't know the length)
nuclear@1	1168 or if stream is only partially open
nuclear@1	1169 */
nuclear@1	1170 ogg_int64_t ov_raw_total(OggVorbis_File *vf,int i){
nuclear@1	1171 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1172 if(!vf->seekable \|\| i>=vf->links)return(OV_EINVAL);
nuclear@1	1173 if(i<0){
nuclear@1	1174 ogg_int64_t acc=0;
nuclear@1	1175 int i;
nuclear@1	1176 for(i=0;i<vf->links;i++)
nuclear@1	1177 acc+=ov_raw_total(vf,i);
nuclear@1	1178 return(acc);
nuclear@1	1179 }else{
nuclear@1	1180 return(vf->offsets[i+1]-vf->offsets[i]);
nuclear@1	1181 }
nuclear@1	1182 }
nuclear@1	1183
nuclear@1	1184 /* returns: total PCM length (samples) of content if i==-1 PCM length
nuclear@1	1185 (samples) of that logical bitstream for i==0 to n
nuclear@1	1186 OV_EINVAL if the stream is not seekable (we can't know the
nuclear@1	1187 length) or only partially open
nuclear@1	1188 */
nuclear@1	1189 ogg_int64_t ov_pcm_total(OggVorbis_File *vf,int i){
nuclear@1	1190 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1191 if(!vf->seekable \|\| i>=vf->links)return(OV_EINVAL);
nuclear@1	1192 if(i<0){
nuclear@1	1193 ogg_int64_t acc=0;
nuclear@1	1194 int i;
nuclear@1	1195 for(i=0;i<vf->links;i++)
nuclear@1	1196 acc+=ov_pcm_total(vf,i);
nuclear@1	1197 return(acc);
nuclear@1	1198 }else{
nuclear@1	1199 return(vf->pcmlengths[i*2+1]);
nuclear@1	1200 }
nuclear@1	1201 }
nuclear@1	1202
nuclear@1	1203 /* returns: total seconds of content if i==-1
nuclear@1	1204 seconds in that logical bitstream for i==0 to n
nuclear@1	1205 OV_EINVAL if the stream is not seekable (we can't know the
nuclear@1	1206 length) or only partially open
nuclear@1	1207 */
nuclear@1	1208 double ov_time_total(OggVorbis_File *vf,int i){
nuclear@1	1209 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1210 if(!vf->seekable \|\| i>=vf->links)return(OV_EINVAL);
nuclear@1	1211 if(i<0){
nuclear@1	1212 double acc=0;
nuclear@1	1213 int i;
nuclear@1	1214 for(i=0;i<vf->links;i++)
nuclear@1	1215 acc+=ov_time_total(vf,i);
nuclear@1	1216 return(acc);
nuclear@1	1217 }else{
nuclear@1	1218 return((double)(vf->pcmlengths[i*2+1])/vf->vi[i].rate);
nuclear@1	1219 }
nuclear@1	1220 }
nuclear@1	1221
nuclear@1	1222 /* seek to an offset relative to the compressed data. This also
nuclear@1	1223 scans packets to update the PCM cursor. It will cross a logical
nuclear@1	1224 bitstream boundary, but only if it can't get any packets out of the
nuclear@1	1225 tail of the bitstream we seek to (so no surprises).
nuclear@1	1226
nuclear@1	1227 returns zero on success, nonzero on failure */
nuclear@1	1228
nuclear@1	1229 int ov_raw_seek(OggVorbis_File *vf,ogg_int64_t pos){
nuclear@1	1230 ogg_stream_state work_os;
nuclear@1	1231 int ret;
nuclear@1	1232
nuclear@1	1233 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1234 if(!vf->seekable)
nuclear@1	1235 return(OV_ENOSEEK); /* don't dump machine if we can't seek */
nuclear@1	1236
nuclear@1	1237 if(pos<0 \|\| pos>vf->end)return(OV_EINVAL);
nuclear@1	1238
nuclear@1	1239 /* is the seek position outside our current link [if any]? */
nuclear@1	1240 if(vf->ready_state>=STREAMSET){
nuclear@1	1241 if(pos<vf->offsets[vf->current_link] \|\| pos>=vf->offsets[vf->current_link+1])
nuclear@1	1242 _decode_clear(vf); /* clear out stream state */
nuclear@1	1243 }
nuclear@1	1244
nuclear@1	1245 /* don't yet clear out decoding machine (if it's initialized), in
nuclear@1	1246 the case we're in the same link. Restart the decode lapping, and
nuclear@1	1247 let _fetch_and_process_packet deal with a potential bitstream
nuclear@1	1248 boundary */
nuclear@1	1249 vf->pcm_offset=-1;
nuclear@1	1250 ogg_stream_reset_serialno(&vf->os,
nuclear@1	1251 vf->current_serialno); /* must set serialno */
nuclear@1	1252 vorbis_synthesis_restart(&vf->vd);
nuclear@1	1253
nuclear@1	1254 ret=_seek_helper(vf,pos);
nuclear@1	1255 if(ret)goto seek_error;
nuclear@1	1256
nuclear@1	1257 /* we need to make sure the pcm_offset is set, but we don't want to
nuclear@1	1258 advance the raw cursor past good packets just to get to the first
nuclear@1	1259 with a granulepos. That's not equivalent behavior to beginning
nuclear@1	1260 decoding as immediately after the seek position as possible.
nuclear@1	1261
nuclear@1	1262 So, a hack. We use two stream states; a local scratch state and
nuclear@1	1263 the shared vf->os stream state. We use the local state to
nuclear@1	1264 scan, and the shared state as a buffer for later decode.
nuclear@1	1265
nuclear@1	1266 Unfortuantely, on the last page we still advance to last packet
nuclear@1	1267 because the granulepos on the last page is not necessarily on a
nuclear@1	1268 packet boundary, and we need to make sure the granpos is
nuclear@1	1269 correct.
nuclear@1	1270 */
nuclear@1	1271
nuclear@1	1272 {
nuclear@1	1273 ogg_page og;
nuclear@1	1274 ogg_packet op;
nuclear@1	1275 int lastblock=0;
nuclear@1	1276 int accblock=0;
nuclear@1	1277 int thisblock=0;
nuclear@1	1278 int lastflag=0;
nuclear@1	1279 int firstflag=0;
nuclear@1	1280 ogg_int64_t pagepos=-1;
nuclear@1	1281
nuclear@1	1282 ogg_stream_init(&work_os,vf->current_serialno); /* get the memory ready */
nuclear@1	1283 ogg_stream_reset(&work_os); /* eliminate the spurious OV_HOLE
nuclear@1	1284 return from not necessarily
nuclear@1	1285 starting from the beginning */
nuclear@1	1286
nuclear@1	1287 while(1){
nuclear@1	1288 if(vf->ready_state>=STREAMSET){
nuclear@1	1289 /* snarf/scan a packet if we can */
nuclear@1	1290 int result=ogg_stream_packetout(&work_os,&op);
nuclear@1	1291
nuclear@1	1292 if(result>0){
nuclear@1	1293
nuclear@1	1294 if(vf->vi[vf->current_link].codec_setup){
nuclear@1	1295 thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op);
nuclear@1	1296 if(thisblock<0){
nuclear@1	1297 ogg_stream_packetout(&vf->os,NULL);
nuclear@1	1298 thisblock=0;
nuclear@1	1299 }else{
nuclear@1	1300
nuclear@1	1301 /* We can't get a guaranteed correct pcm position out of the
nuclear@1	1302 last page in a stream because it might have a 'short'
nuclear@1	1303 granpos, which can only be detected in the presence of a
nuclear@1	1304 preceding page. However, if the last page is also the first
nuclear@1	1305 page, the granpos rules of a first page take precedence. Not
nuclear@1	1306 only that, but for first==last, the EOS page must be treated
nuclear@1	1307 as if its a normal first page for the stream to open/play. */
nuclear@1	1308 if(lastflag && !firstflag)
nuclear@1	1309 ogg_stream_packetout(&vf->os,NULL);
nuclear@1	1310 else
nuclear@1	1311 if(lastblock)accblock+=(lastblock+thisblock)>>2;
nuclear@1	1312 }
nuclear@1	1313
nuclear@1	1314 if(op.granulepos!=-1){
nuclear@1	1315 int i,link=vf->current_link;
nuclear@1	1316 ogg_int64_t granulepos=op.granulepos-vf->pcmlengths[link*2];
nuclear@1	1317 if(granulepos<0)granulepos=0;
nuclear@1	1318
nuclear@1	1319 for(i=0;i<link;i++)
nuclear@1	1320 granulepos+=vf->pcmlengths[i*2+1];
nuclear@1	1321 vf->pcm_offset=granulepos-accblock;
nuclear@1	1322 if(vf->pcm_offset<0)vf->pcm_offset=0;
nuclear@1	1323 break;
nuclear@1	1324 }
nuclear@1	1325 lastblock=thisblock;
nuclear@1	1326 continue;
nuclear@1	1327 }else
nuclear@1	1328 ogg_stream_packetout(&vf->os,NULL);
nuclear@1	1329 }
nuclear@1	1330 }
nuclear@1	1331
nuclear@1	1332 if(!lastblock){
nuclear@1	1333 pagepos=_get_next_page(vf,&og,-1);
nuclear@1	1334 if(pagepos<0){
nuclear@1	1335 vf->pcm_offset=ov_pcm_total(vf,-1);
nuclear@1	1336 break;
nuclear@1	1337 }
nuclear@1	1338 }else{
nuclear@1	1339 /* huh? Bogus stream with packets but no granulepos */
nuclear@1	1340 vf->pcm_offset=-1;
nuclear@1	1341 break;
nuclear@1	1342 }
nuclear@1	1343
nuclear@1	1344 /* has our decoding just traversed a bitstream boundary? */
nuclear@1	1345 if(vf->ready_state>=STREAMSET){
nuclear@1	1346 if(vf->current_serialno!=ogg_page_serialno(&og)){
nuclear@1	1347
nuclear@1	1348 /* two possibilities:
nuclear@1	1349 1) our decoding just traversed a bitstream boundary
nuclear@1	1350 2) another stream is multiplexed into this logical section? */
nuclear@1	1351
nuclear@1	1352 if(ogg_page_bos(&og)){
nuclear@1	1353 /* we traversed */
nuclear@1	1354 _decode_clear(vf); /* clear out stream state */
nuclear@1	1355 ogg_stream_clear(&work_os);
nuclear@1	1356 } /* else, do nothing; next loop will scoop another page */
nuclear@1	1357 }
nuclear@1	1358 }
nuclear@1	1359
nuclear@1	1360 if(vf->ready_state<STREAMSET){
nuclear@1	1361 int link;
nuclear@1	1362 long serialno = ogg_page_serialno(&og);
nuclear@1	1363
nuclear@1	1364 for(link=0;link<vf->links;link++)
nuclear@1	1365 if(vf->serialnos[link]==serialno)break;
nuclear@1	1366
nuclear@1	1367 if(link==vf->links) continue; /* not the desired Vorbis
nuclear@1	1368 bitstream section; keep
nuclear@1	1369 trying */
nuclear@1	1370 vf->current_link=link;
nuclear@1	1371 vf->current_serialno=serialno;
nuclear@1	1372 ogg_stream_reset_serialno(&vf->os,serialno);
nuclear@1	1373 ogg_stream_reset_serialno(&work_os,serialno);
nuclear@1	1374 vf->ready_state=STREAMSET;
nuclear@1	1375 firstflag=(pagepos<=vf->dataoffsets[link]);
nuclear@1	1376 }
nuclear@1	1377
nuclear@1	1378 ogg_stream_pagein(&vf->os,&og);
nuclear@1	1379 ogg_stream_pagein(&work_os,&og);
nuclear@1	1380 lastflag=ogg_page_eos(&og);
nuclear@1	1381
nuclear@1	1382 }
nuclear@1	1383 }
nuclear@1	1384
nuclear@1	1385 ogg_stream_clear(&work_os);
nuclear@1	1386 vf->bittrack=0.f;
nuclear@1	1387 vf->samptrack=0.f;
nuclear@1	1388 return(0);
nuclear@1	1389
nuclear@1	1390 seek_error:
nuclear@1	1391 /* dump the machine so we're in a known state */
nuclear@1	1392 vf->pcm_offset=-1;
nuclear@1	1393 ogg_stream_clear(&work_os);
nuclear@1	1394 _decode_clear(vf);
nuclear@1	1395 return OV_EBADLINK;
nuclear@1	1396 }
nuclear@1	1397
nuclear@1	1398 /* Page granularity seek (faster than sample granularity because we
nuclear@1	1399 don't do the last bit of decode to find a specific sample).
nuclear@1	1400
nuclear@1	1401 Seek to the last [granule marked] page preceding the specified pos
nuclear@1	1402 location, such that decoding past the returned point will quickly
nuclear@1	1403 arrive at the requested position. */
nuclear@1	1404 int ov_pcm_seek_page(OggVorbis_File *vf,ogg_int64_t pos){
nuclear@1	1405 int link=-1;
nuclear@1	1406 ogg_int64_t result=0;
nuclear@1	1407 ogg_int64_t total=ov_pcm_total(vf,-1);
nuclear@1	1408
nuclear@1	1409 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1410 if(!vf->seekable)return(OV_ENOSEEK);
nuclear@1	1411
nuclear@1	1412 if(pos<0 \|\| pos>total)return(OV_EINVAL);
nuclear@1	1413
nuclear@1	1414 /* which bitstream section does this pcm offset occur in? */
nuclear@1	1415 for(link=vf->links-1;link>=0;link--){
nuclear@1	1416 total-=vf->pcmlengths[link*2+1];
nuclear@1	1417 if(pos>=total)break;
nuclear@1	1418 }
nuclear@1	1419
nuclear@1	1420 /* search within the logical bitstream for the page with the highest
nuclear@1	1421 pcm_pos preceding (or equal to) pos. There is a danger here;
nuclear@1	1422 missing pages or incorrect frame number information in the
nuclear@1	1423 bitstream could make our task impossible. Account for that (it
nuclear@1	1424 would be an error condition) */
nuclear@1	1425
nuclear@1	1426 /* new search algorithm by HB (Nicholas Vinen) */
nuclear@1	1427 {
nuclear@1	1428 ogg_int64_t end=vf->offsets[link+1];
nuclear@1	1429 ogg_int64_t begin=vf->offsets[link];
nuclear@1	1430 ogg_int64_t begintime = vf->pcmlengths[link*2];
nuclear@1	1431 ogg_int64_t endtime = vf->pcmlengths[link*2+1]+begintime;
nuclear@1	1432 ogg_int64_t target=pos-total+begintime;
nuclear@1	1433 ogg_int64_t best=begin;
nuclear@1	1434
nuclear@1	1435 ogg_page og;
nuclear@1	1436 while(begin<end){
nuclear@1	1437 ogg_int64_t bisect;
nuclear@1	1438
nuclear@1	1439 if(end-begin<CHUNKSIZE){
nuclear@1	1440 bisect=begin;
nuclear@1	1441 }else{
nuclear@1	1442 /* take a (pretty decent) guess. */
nuclear@1	1443 bisect=begin +
nuclear@1	1444 (ogg_int64_t)((double)(target-begintime)*(end-begin)/(endtime-begintime))
nuclear@1	1445 - CHUNKSIZE;
nuclear@1	1446 if(bisect<begin+CHUNKSIZE)
nuclear@1	1447 bisect=begin;
nuclear@1	1448 }
nuclear@1	1449
nuclear@1	1450 if(bisect!=vf->offset){
nuclear@1	1451 result=_seek_helper(vf,bisect);
nuclear@1	1452 if(result) goto seek_error;
nuclear@1	1453 }
nuclear@1	1454
nuclear@1	1455 while(begin<end){
nuclear@1	1456 result=_get_next_page(vf,&og,end-vf->offset);
nuclear@1	1457 if(result==OV_EREAD) goto seek_error;
nuclear@1	1458 if(result<0){
nuclear@1	1459 if(bisect<=begin+1)
nuclear@1	1460 end=begin; /* found it */
nuclear@1	1461 else{
nuclear@1	1462 if(bisect==0) goto seek_error;
nuclear@1	1463 bisect-=CHUNKSIZE;
nuclear@1	1464 if(bisect<=begin)bisect=begin+1;
nuclear@1	1465 result=_seek_helper(vf,bisect);
nuclear@1	1466 if(result) goto seek_error;
nuclear@1	1467 }
nuclear@1	1468 }else{
nuclear@1	1469 ogg_int64_t granulepos;
nuclear@1	1470
nuclear@1	1471 if(ogg_page_serialno(&og)!=vf->serialnos[link])
nuclear@1	1472 continue;
nuclear@1	1473
nuclear@1	1474 granulepos=ogg_page_granulepos(&og);
nuclear@1	1475 if(granulepos==-1)continue;
nuclear@1	1476
nuclear@1	1477 if(granulepos<target){
nuclear@1	1478 best=result; /* raw offset of packet with granulepos */
nuclear@1	1479 begin=vf->offset; /* raw offset of next page */
nuclear@1	1480 begintime=granulepos;
nuclear@1	1481
nuclear@1	1482 if(target-begintime>44100)break;
nuclear@1	1483 bisect=begin; /* not begin + 1 */
nuclear@1	1484 }else{
nuclear@1	1485 if(bisect<=begin+1)
nuclear@1	1486 end=begin; /* found it */
nuclear@1	1487 else{
nuclear@1	1488 if(end==vf->offset){ /* we're pretty close - we'd be stuck in */
nuclear@1	1489 end=result;
nuclear@1	1490 bisect-=CHUNKSIZE; /* an endless loop otherwise. */
nuclear@1	1491 if(bisect<=begin)bisect=begin+1;
nuclear@1	1492 result=_seek_helper(vf,bisect);
nuclear@1	1493 if(result) goto seek_error;
nuclear@1	1494 }else{
nuclear@1	1495 end=bisect;
nuclear@1	1496 endtime=granulepos;
nuclear@1	1497 break;
nuclear@1	1498 }
nuclear@1	1499 }
nuclear@1	1500 }
nuclear@1	1501 }
nuclear@1	1502 }
nuclear@1	1503 }
nuclear@1	1504
nuclear@1	1505 /* found our page. seek to it, update pcm offset. Easier case than
nuclear@1	1506 raw_seek, don't keep packets preceding granulepos. */
nuclear@1	1507 {
nuclear@1	1508 ogg_page og;
nuclear@1	1509 ogg_packet op;
nuclear@1	1510
nuclear@1	1511 /* seek */
nuclear@1	1512 result=_seek_helper(vf,best);
nuclear@1	1513 vf->pcm_offset=-1;
nuclear@1	1514 if(result) goto seek_error;
nuclear@1	1515 result=_get_next_page(vf,&og,-1);
nuclear@1	1516 if(result<0) goto seek_error;
nuclear@1	1517
nuclear@1	1518 if(link!=vf->current_link){
nuclear@1	1519 /* Different link; dump entire decode machine */
nuclear@1	1520 _decode_clear(vf);
nuclear@1	1521
nuclear@1	1522 vf->current_link=link;
nuclear@1	1523 vf->current_serialno=vf->serialnos[link];
nuclear@1	1524 vf->ready_state=STREAMSET;
nuclear@1	1525
nuclear@1	1526 }else{
nuclear@1	1527 vorbis_synthesis_restart(&vf->vd);
nuclear@1	1528 }
nuclear@1	1529
nuclear@1	1530 ogg_stream_reset_serialno(&vf->os,vf->current_serialno);
nuclear@1	1531 ogg_stream_pagein(&vf->os,&og);
nuclear@1	1532
nuclear@1	1533 /* pull out all but last packet; the one with granulepos */
nuclear@1	1534 while(1){
nuclear@1	1535 result=ogg_stream_packetpeek(&vf->os,&op);
nuclear@1	1536 if(result==0){
nuclear@1	1537 /* !!! the packet finishing this page originated on a
nuclear@1	1538 preceding page. Keep fetching previous pages until we
nuclear@1	1539 get one with a granulepos or without the 'continued' flag
nuclear@1	1540 set. Then just use raw_seek for simplicity. */
nuclear@1	1541
nuclear@1	1542 result=_seek_helper(vf,best);
nuclear@1	1543 if(result<0) goto seek_error;
nuclear@1	1544
nuclear@1	1545 while(1){
nuclear@1	1546 result=_get_prev_page(vf,&og);
nuclear@1	1547 if(result<0) goto seek_error;
nuclear@1	1548 if(ogg_page_serialno(&og)==vf->current_serialno &&
nuclear@1	1549 (ogg_page_granulepos(&og)>-1 \|\|
nuclear@1	1550 !ogg_page_continued(&og))){
nuclear@1	1551 return ov_raw_seek(vf,result);
nuclear@1	1552 }
nuclear@1	1553 vf->offset=result;
nuclear@1	1554 }
nuclear@1	1555 }
nuclear@1	1556 if(result<0){
nuclear@1	1557 result = OV_EBADPACKET;
nuclear@1	1558 goto seek_error;
nuclear@1	1559 }
nuclear@1	1560 if(op.granulepos!=-1){
nuclear@1	1561 vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2];
nuclear@1	1562 if(vf->pcm_offset<0)vf->pcm_offset=0;
nuclear@1	1563 vf->pcm_offset+=total;
nuclear@1	1564 break;
nuclear@1	1565 }else
nuclear@1	1566 result=ogg_stream_packetout(&vf->os,NULL);
nuclear@1	1567 }
nuclear@1	1568 }
nuclear@1	1569 }
nuclear@1	1570
nuclear@1	1571 /* verify result */
nuclear@1	1572 if(vf->pcm_offset>pos \|\| pos>ov_pcm_total(vf,-1)){
nuclear@1	1573 result=OV_EFAULT;
nuclear@1	1574 goto seek_error;
nuclear@1	1575 }
nuclear@1	1576 vf->bittrack=0.f;
nuclear@1	1577 vf->samptrack=0.f;
nuclear@1	1578 return(0);
nuclear@1	1579
nuclear@1	1580 seek_error:
nuclear@1	1581 /* dump machine so we're in a known state */
nuclear@1	1582 vf->pcm_offset=-1;
nuclear@1	1583 _decode_clear(vf);
nuclear@1	1584 return (int)result;
nuclear@1	1585 }
nuclear@1	1586
nuclear@1	1587 /* seek to a sample offset relative to the decompressed pcm stream
nuclear@1	1588 returns zero on success, nonzero on failure */
nuclear@1	1589
nuclear@1	1590 int ov_pcm_seek(OggVorbis_File *vf,ogg_int64_t pos){
nuclear@1	1591 int thisblock,lastblock=0;
nuclear@1	1592 int ret=ov_pcm_seek_page(vf,pos);
nuclear@1	1593 if(ret<0)return(ret);
nuclear@1	1594 if((ret=_make_decode_ready(vf)))return ret;
nuclear@1	1595
nuclear@1	1596 /* discard leading packets we don't need for the lapping of the
nuclear@1	1597 position we want; don't decode them */
nuclear@1	1598
nuclear@1	1599 while(1){
nuclear@1	1600 ogg_packet op;
nuclear@1	1601 ogg_page og;
nuclear@1	1602
nuclear@1	1603 int ret=ogg_stream_packetpeek(&vf->os,&op);
nuclear@1	1604 if(ret>0){
nuclear@1	1605 thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op);
nuclear@1	1606 if(thisblock<0){
nuclear@1	1607 ogg_stream_packetout(&vf->os,NULL);
nuclear@1	1608 continue; /* non audio packet */
nuclear@1	1609 }
nuclear@1	1610 if(lastblock)vf->pcm_offset+=(lastblock+thisblock)>>2;
nuclear@1	1611
nuclear@1	1612 if(vf->pcm_offset+((thisblock+
nuclear@1	1613 vorbis_info_blocksize(vf->vi,1))>>2)>=pos)break;
nuclear@1	1614
nuclear@1	1615 /* remove the packet from packet queue and track its granulepos */
nuclear@1	1616 ogg_stream_packetout(&vf->os,NULL);
nuclear@1	1617 vorbis_synthesis_trackonly(&vf->vb,&op); /* set up a vb with
nuclear@1	1618 only tracking, no
nuclear@1	1619 pcm_decode */
nuclear@1	1620 vorbis_synthesis_blockin(&vf->vd,&vf->vb);
nuclear@1	1621
nuclear@1	1622 /* end of logical stream case is hard, especially with exact
nuclear@1	1623 length positioning. */
nuclear@1	1624
nuclear@1	1625 if(op.granulepos>-1){
nuclear@1	1626 int i;
nuclear@1	1627 /* always believe the stream markers */
nuclear@1	1628 vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2];
nuclear@1	1629 if(vf->pcm_offset<0)vf->pcm_offset=0;
nuclear@1	1630 for(i=0;i<vf->current_link;i++)
nuclear@1	1631 vf->pcm_offset+=vf->pcmlengths[i*2+1];
nuclear@1	1632 }
nuclear@1	1633
nuclear@1	1634 lastblock=thisblock;
nuclear@1	1635
nuclear@1	1636 }else{
nuclear@1	1637 if(ret<0 && ret!=OV_HOLE)break;
nuclear@1	1638
nuclear@1	1639 /* suck in a new page */
nuclear@1	1640 if(_get_next_page(vf,&og,-1)<0)break;
nuclear@1	1641 if(ogg_page_bos(&og))_decode_clear(vf);
nuclear@1	1642
nuclear@1	1643 if(vf->ready_state<STREAMSET){
nuclear@1	1644 long serialno=ogg_page_serialno(&og);
nuclear@1	1645 int link;
nuclear@1	1646
nuclear@1	1647 for(link=0;link<vf->links;link++)
nuclear@1	1648 if(vf->serialnos[link]==serialno)break;
nuclear@1	1649 if(link==vf->links) continue;
nuclear@1	1650 vf->current_link=link;
nuclear@1	1651
nuclear@1	1652 vf->ready_state=STREAMSET;
nuclear@1	1653 vf->current_serialno=ogg_page_serialno(&og);
nuclear@1	1654 ogg_stream_reset_serialno(&vf->os,serialno);
nuclear@1	1655 ret=_make_decode_ready(vf);
nuclear@1	1656 if(ret)return ret;
nuclear@1	1657 lastblock=0;
nuclear@1	1658 }
nuclear@1	1659
nuclear@1	1660 ogg_stream_pagein(&vf->os,&og);
nuclear@1	1661 }
nuclear@1	1662 }
nuclear@1	1663
nuclear@1	1664 vf->bittrack=0.f;
nuclear@1	1665 vf->samptrack=0.f;
nuclear@1	1666 /* discard samples until we reach the desired position. Crossing a
nuclear@1	1667 logical bitstream boundary with abandon is OK. */
nuclear@1	1668 {
nuclear@1	1669 /* note that halfrate could be set differently in each link, but
nuclear@1	1670 vorbisfile encoforces all links are set or unset */
nuclear@1	1671 int hs=vorbis_synthesis_halfrate_p(vf->vi);
nuclear@1	1672 while(vf->pcm_offset<((pos>>hs)<<hs)){
nuclear@1	1673 ogg_int64_t target=(pos-vf->pcm_offset)>>hs;
nuclear@1	1674 long samples=vorbis_synthesis_pcmout(&vf->vd,NULL);
nuclear@1	1675
nuclear@1	1676 if(samples>target)samples=target;
nuclear@1	1677 vorbis_synthesis_read(&vf->vd,samples);
nuclear@1	1678 vf->pcm_offset+=samples<<hs;
nuclear@1	1679
nuclear@1	1680 if(samples<target)
nuclear@1	1681 if(_fetch_and_process_packet(vf,NULL,1,1)<=0)
nuclear@1	1682 vf->pcm_offset=ov_pcm_total(vf,-1); /* eof */
nuclear@1	1683 }
nuclear@1	1684 }
nuclear@1	1685 return 0;
nuclear@1	1686 }
nuclear@1	1687
nuclear@1	1688 /* seek to a playback time relative to the decompressed pcm stream
nuclear@1	1689 returns zero on success, nonzero on failure */
nuclear@1	1690 int ov_time_seek(OggVorbis_File *vf,double seconds){
nuclear@1	1691 /* translate time to PCM position and call ov_pcm_seek */
nuclear@1	1692
nuclear@1	1693 int link=-1;
nuclear@1	1694 ogg_int64_t pcm_total=0;
nuclear@1	1695 double time_total=0.;
nuclear@1	1696
nuclear@1	1697 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1698 if(!vf->seekable)return(OV_ENOSEEK);
nuclear@1	1699 if(seconds<0)return(OV_EINVAL);
nuclear@1	1700
nuclear@1	1701 /* which bitstream section does this time offset occur in? */
nuclear@1	1702 for(link=0;link<vf->links;link++){
nuclear@1	1703 double addsec = ov_time_total(vf,link);
nuclear@1	1704 if(seconds<time_total+addsec)break;
nuclear@1	1705 time_total+=addsec;
nuclear@1	1706 pcm_total+=vf->pcmlengths[link*2+1];
nuclear@1	1707 }
nuclear@1	1708
nuclear@1	1709 if(link==vf->links)return(OV_EINVAL);
nuclear@1	1710
nuclear@1	1711 /* enough information to convert time offset to pcm offset */
nuclear@1	1712 {
nuclear@1	1713 ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate;
nuclear@1	1714 return(ov_pcm_seek(vf,target));
nuclear@1	1715 }
nuclear@1	1716 }
nuclear@1	1717
nuclear@1	1718 /* page-granularity version of ov_time_seek
nuclear@1	1719 returns zero on success, nonzero on failure */
nuclear@1	1720 int ov_time_seek_page(OggVorbis_File *vf,double seconds){
nuclear@1	1721 /* translate time to PCM position and call ov_pcm_seek */
nuclear@1	1722
nuclear@1	1723 int link=-1;
nuclear@1	1724 ogg_int64_t pcm_total=0;
nuclear@1	1725 double time_total=0.;
nuclear@1	1726
nuclear@1	1727 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1728 if(!vf->seekable)return(OV_ENOSEEK);
nuclear@1	1729 if(seconds<0)return(OV_EINVAL);
nuclear@1	1730
nuclear@1	1731 /* which bitstream section does this time offset occur in? */
nuclear@1	1732 for(link=0;link<vf->links;link++){
nuclear@1	1733 double addsec = ov_time_total(vf,link);
nuclear@1	1734 if(seconds<time_total+addsec)break;
nuclear@1	1735 time_total+=addsec;
nuclear@1	1736 pcm_total+=vf->pcmlengths[link*2+1];
nuclear@1	1737 }
nuclear@1	1738
nuclear@1	1739 if(link==vf->links)return(OV_EINVAL);
nuclear@1	1740
nuclear@1	1741 /* enough information to convert time offset to pcm offset */
nuclear@1	1742 {
nuclear@1	1743 ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate;
nuclear@1	1744 return(ov_pcm_seek_page(vf,target));
nuclear@1	1745 }
nuclear@1	1746 }
nuclear@1	1747
nuclear@1	1748 /* tell the current stream offset cursor. Note that seek followed by
nuclear@1	1749 tell will likely not give the set offset due to caching */
nuclear@1	1750 ogg_int64_t ov_raw_tell(OggVorbis_File *vf){
nuclear@1	1751 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1752 return(vf->offset);
nuclear@1	1753 }
nuclear@1	1754
nuclear@1	1755 /* return PCM offset (sample) of next PCM sample to be read */
nuclear@1	1756 ogg_int64_t ov_pcm_tell(OggVorbis_File *vf){
nuclear@1	1757 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1758 return(vf->pcm_offset);
nuclear@1	1759 }
nuclear@1	1760
nuclear@1	1761 /* return time offset (seconds) of next PCM sample to be read */
nuclear@1	1762 double ov_time_tell(OggVorbis_File *vf){
nuclear@1	1763 int link=0;
nuclear@1	1764 ogg_int64_t pcm_total=0;
nuclear@1	1765 double time_total=0.f;
nuclear@1	1766
nuclear@1	1767 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1768 if(vf->seekable){
nuclear@1	1769 pcm_total=ov_pcm_total(vf,-1);
nuclear@1	1770 time_total=ov_time_total(vf,-1);
nuclear@1	1771
nuclear@1	1772 /* which bitstream section does this time offset occur in? */
nuclear@1	1773 for(link=vf->links-1;link>=0;link--){
nuclear@1	1774 pcm_total-=vf->pcmlengths[link*2+1];
nuclear@1	1775 time_total-=ov_time_total(vf,link);
nuclear@1	1776 if(vf->pcm_offset>=pcm_total)break;
nuclear@1	1777 }
nuclear@1	1778 }
nuclear@1	1779
nuclear@1	1780 return((double)time_total+(double)(vf->pcm_offset-pcm_total)/vf->vi[link].rate);
nuclear@1	1781 }
nuclear@1	1782
nuclear@1	1783 /* link: -1) return the vorbis_info struct for the bitstream section
nuclear@1	1784 currently being decoded
nuclear@1	1785 0-n) to request information for a specific bitstream section
nuclear@1	1786
nuclear@1	1787 In the case of a non-seekable bitstream, any call returns the
nuclear@1	1788 current bitstream. NULL in the case that the machine is not
nuclear@1	1789 initialized */
nuclear@1	1790
nuclear@1	1791 vorbis_info ov_info(OggVorbis_File vf,int link){
nuclear@1	1792 if(vf->seekable){
nuclear@1	1793 if(link<0)
nuclear@1	1794 if(vf->ready_state>=STREAMSET)
nuclear@1	1795 return vf->vi+vf->current_link;
nuclear@1	1796 else
nuclear@1	1797 return vf->vi;
nuclear@1	1798 else
nuclear@1	1799 if(link>=vf->links)
nuclear@1	1800 return NULL;
nuclear@1	1801 else
nuclear@1	1802 return vf->vi+link;
nuclear@1	1803 }else{
nuclear@1	1804 return vf->vi;
nuclear@1	1805 }
nuclear@1	1806 }
nuclear@1	1807
nuclear@1	1808 /* grr, strong typing, grr, no templates/inheritence, grr */
nuclear@1	1809 vorbis_comment ov_comment(OggVorbis_File vf,int link){
nuclear@1	1810 if(vf->seekable){
nuclear@1	1811 if(link<0)
nuclear@1	1812 if(vf->ready_state>=STREAMSET)
nuclear@1	1813 return vf->vc+vf->current_link;
nuclear@1	1814 else
nuclear@1	1815 return vf->vc;
nuclear@1	1816 else
nuclear@1	1817 if(link>=vf->links)
nuclear@1	1818 return NULL;
nuclear@1	1819 else
nuclear@1	1820 return vf->vc+link;
nuclear@1	1821 }else{
nuclear@1	1822 return vf->vc;
nuclear@1	1823 }
nuclear@1	1824 }
nuclear@1	1825
nuclear@1	1826 static int host_is_big_endian() {
nuclear@1	1827 ogg_int32_t pattern = 0xfeedface; /* deadbeef */
nuclear@1	1828 unsigned char bytewise = (unsigned char )&pattern;
nuclear@1	1829 if (bytewise[0] == 0xfe) return 1;
nuclear@1	1830 return 0;
nuclear@1	1831 }
nuclear@1	1832
nuclear@1	1833 /* up to this point, everything could more or less hide the multiple
nuclear@1	1834 logical bitstream nature of chaining from the toplevel application
nuclear@1	1835 if the toplevel application didn't particularly care. However, at
nuclear@1	1836 the point that we actually read audio back, the multiple-section
nuclear@1	1837 nature must surface: Multiple bitstream sections do not necessarily
nuclear@1	1838 have to have the same number of channels or sampling rate.
nuclear@1	1839
nuclear@1	1840 ov_read returns the sequential logical bitstream number currently
nuclear@1	1841 being decoded along with the PCM data in order that the toplevel
nuclear@1	1842 application can take action on channel/sample rate changes. This
nuclear@1	1843 number will be incremented even for streamed (non-seekable) streams
nuclear@1	1844 (for seekable streams, it represents the actual logical bitstream
nuclear@1	1845 index within the physical bitstream. Note that the accessor
nuclear@1	1846 functions above are aware of this dichotomy).
nuclear@1	1847
nuclear@1	1848 ov_read_filter is exactly the same as ov_read except that it processes
nuclear@1	1849 the decoded audio data through a filter before packing it into the
nuclear@1	1850 requested format. This gives greater accuracy than applying a filter
nuclear@1	1851 after the audio has been converted into integral PCM.
nuclear@1	1852
nuclear@1	1853 input values: buffer) a buffer to hold packed PCM data for return
nuclear@1	1854 length) the byte length requested to be placed into buffer
nuclear@1	1855 bigendianp) should the data be packed LSB first (0) or
nuclear@1	1856 MSB first (1)
nuclear@1	1857 word) word size for output. currently 1 (byte) or
nuclear@1	1858 2 (16 bit short)
nuclear@1	1859
nuclear@1	1860 return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL)
nuclear@1	1861 0) EOF
nuclear@1	1862 n) number of bytes of PCM actually returned. The
nuclear@1	1863 below works on a packet-by-packet basis, so the
nuclear@1	1864 return length is not related to the 'length' passed
nuclear@1	1865 in, just guaranteed to fit.
nuclear@1	1866
nuclear@1	1867 section) set to the logical bitstream number /
nuclear@1	1868
nuclear@1	1869 long ov_read_filter(OggVorbis_File vf,char buffer,int length,
nuclear@1	1870 int bigendianp,int word,int sgned,int *bitstream,
nuclear@1	1871 void (filter)(float pcm,long channels,long samples,void filter_param),void *filter_param){
nuclear@1	1872 int i,j;
nuclear@1	1873 int host_endian = host_is_big_endian();
nuclear@1	1874 int hs;
nuclear@1	1875
nuclear@1	1876 float **pcm;
nuclear@1	1877 long samples;
nuclear@1	1878
nuclear@1	1879 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	1880
nuclear@1	1881 while(1){
nuclear@1	1882 if(vf->ready_state==INITSET){
nuclear@1	1883 samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
nuclear@1	1884 if(samples)break;
nuclear@1	1885 }
nuclear@1	1886
nuclear@1	1887 /* suck in another packet */
nuclear@1	1888 {
nuclear@1	1889 int ret=_fetch_and_process_packet(vf,NULL,1,1);
nuclear@1	1890 if(ret==OV_EOF)
nuclear@1	1891 return(0);
nuclear@1	1892 if(ret<=0)
nuclear@1	1893 return(ret);
nuclear@1	1894 }
nuclear@1	1895
nuclear@1	1896 }
nuclear@1	1897
nuclear@1	1898 if(samples>0){
nuclear@1	1899
nuclear@1	1900 /* yay! proceed to pack data into the byte buffer */
nuclear@1	1901
nuclear@1	1902 long channels=ov_info(vf,-1)->channels;
nuclear@1	1903 long bytespersample=word * channels;
nuclear@1	1904 vorbis_fpu_control fpu;
nuclear@1	1905 if(samples>length/bytespersample)samples=length/bytespersample;
nuclear@1	1906
nuclear@1	1907 if(samples <= 0)
nuclear@1	1908 return OV_EINVAL;
nuclear@1	1909
nuclear@1	1910 /* Here. */
nuclear@1	1911 if(filter)
nuclear@1	1912 filter(pcm,channels,samples,filter_param);
nuclear@1	1913
nuclear@1	1914 /* a tight loop to pack each size */
nuclear@1	1915 {
nuclear@1	1916 int val;
nuclear@1	1917 if(word==1){
nuclear@1	1918 int off=(sgned?0:128);
nuclear@1	1919 vorbis_fpu_setround(&fpu);
nuclear@1	1920 for(j=0;j<samples;j++)
nuclear@1	1921 for(i=0;i<channels;i++){
nuclear@1	1922 val=vorbis_ftoi(pcm[i][j]*128.f);
nuclear@1	1923 if(val>127)val=127;
nuclear@1	1924 else if(val<-128)val=-128;
nuclear@1	1925 *buffer++=val+off;
nuclear@1	1926 }
nuclear@1	1927 vorbis_fpu_restore(fpu);
nuclear@1	1928 }else{
nuclear@1	1929 int off=(sgned?0:32768);
nuclear@1	1930
nuclear@1	1931 if(host_endian==bigendianp){
nuclear@1	1932 if(sgned){
nuclear@1	1933
nuclear@1	1934 vorbis_fpu_setround(&fpu);
nuclear@1	1935 for(i=0;i<channels;i++) { /* It's faster in this order */
nuclear@1	1936 float *src=pcm[i];
nuclear@1	1937 short dest=((short )buffer)+i;
nuclear@1	1938 for(j=0;j<samples;j++) {
nuclear@1	1939 val=vorbis_ftoi(src[j]*32768.f);
nuclear@1	1940 if(val>32767)val=32767;
nuclear@1	1941 else if(val<-32768)val=-32768;
nuclear@1	1942 *dest=val;
nuclear@1	1943 dest+=channels;
nuclear@1	1944 }
nuclear@1	1945 }
nuclear@1	1946 vorbis_fpu_restore(fpu);
nuclear@1	1947
nuclear@1	1948 }else{
nuclear@1	1949
nuclear@1	1950 vorbis_fpu_setround(&fpu);
nuclear@1	1951 for(i=0;i<channels;i++) {
nuclear@1	1952 float *src=pcm[i];
nuclear@1	1953 short dest=((short )buffer)+i;
nuclear@1	1954 for(j=0;j<samples;j++) {
nuclear@1	1955 val=vorbis_ftoi(src[j]*32768.f);
nuclear@1	1956 if(val>32767)val=32767;
nuclear@1	1957 else if(val<-32768)val=-32768;
nuclear@1	1958 *dest=val+off;
nuclear@1	1959 dest+=channels;
nuclear@1	1960 }
nuclear@1	1961 }
nuclear@1	1962 vorbis_fpu_restore(fpu);
nuclear@1	1963
nuclear@1	1964 }
nuclear@1	1965 }else if(bigendianp){
nuclear@1	1966
nuclear@1	1967 vorbis_fpu_setround(&fpu);
nuclear@1	1968 for(j=0;j<samples;j++)
nuclear@1	1969 for(i=0;i<channels;i++){
nuclear@1	1970 val=vorbis_ftoi(pcm[i][j]*32768.f);
nuclear@1	1971 if(val>32767)val=32767;
nuclear@1	1972 else if(val<-32768)val=-32768;
nuclear@1	1973 val+=off;
nuclear@1	1974 *buffer++=(val>>8);
nuclear@1	1975 *buffer++=(val&0xff);
nuclear@1	1976 }
nuclear@1	1977 vorbis_fpu_restore(fpu);
nuclear@1	1978
nuclear@1	1979 }else{
nuclear@1	1980 int val;
nuclear@1	1981 vorbis_fpu_setround(&fpu);
nuclear@1	1982 for(j=0;j<samples;j++)
nuclear@1	1983 for(i=0;i<channels;i++){
nuclear@1	1984 val=vorbis_ftoi(pcm[i][j]*32768.f);
nuclear@1	1985 if(val>32767)val=32767;
nuclear@1	1986 else if(val<-32768)val=-32768;
nuclear@1	1987 val+=off;
nuclear@1	1988 *buffer++=(val&0xff);
nuclear@1	1989 *buffer++=(val>>8);
nuclear@1	1990 }
nuclear@1	1991 vorbis_fpu_restore(fpu);
nuclear@1	1992
nuclear@1	1993 }
nuclear@1	1994 }
nuclear@1	1995 }
nuclear@1	1996
nuclear@1	1997 vorbis_synthesis_read(&vf->vd,samples);
nuclear@1	1998 hs=vorbis_synthesis_halfrate_p(vf->vi);
nuclear@1	1999 vf->pcm_offset+=(samples<<hs);
nuclear@1	2000 if(bitstream)*bitstream=vf->current_link;
nuclear@1	2001 return(samples*bytespersample);
nuclear@1	2002 }else{
nuclear@1	2003 return(samples);
nuclear@1	2004 }
nuclear@1	2005 }
nuclear@1	2006
nuclear@1	2007 long ov_read(OggVorbis_File vf,char buffer,int length,
nuclear@1	2008 int bigendianp,int word,int sgned,int *bitstream){
nuclear@1	2009 return ov_read_filter(vf, buffer, length, bigendianp, word, sgned, bitstream, NULL, NULL);
nuclear@1	2010 }
nuclear@1	2011
nuclear@1	2012 /* input values: pcm_channels) a float vector per channel of output
nuclear@1	2013 length) the sample length being read by the app
nuclear@1	2014
nuclear@1	2015 return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL)
nuclear@1	2016 0) EOF
nuclear@1	2017 n) number of samples of PCM actually returned. The
nuclear@1	2018 below works on a packet-by-packet basis, so the
nuclear@1	2019 return length is not related to the 'length' passed
nuclear@1	2020 in, just guaranteed to fit.
nuclear@1	2021
nuclear@1	2022 section) set to the logical bitstream number /
nuclear@1	2023
nuclear@1	2024
nuclear@1	2025
nuclear@1	2026 long ov_read_float(OggVorbis_File vf,float **pcm_channels,int length,
nuclear@1	2027 int *bitstream){
nuclear@1	2028
nuclear@1	2029 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	2030
nuclear@1	2031 while(1){
nuclear@1	2032 if(vf->ready_state==INITSET){
nuclear@1	2033 float **pcm;
nuclear@1	2034 long samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
nuclear@1	2035 if(samples){
nuclear@1	2036 int hs=vorbis_synthesis_halfrate_p(vf->vi);
nuclear@1	2037 if(pcm_channels)*pcm_channels=pcm;
nuclear@1	2038 if(samples>length)samples=length;
nuclear@1	2039 vorbis_synthesis_read(&vf->vd,samples);
nuclear@1	2040 vf->pcm_offset+=samples<<hs;
nuclear@1	2041 if(bitstream)*bitstream=vf->current_link;
nuclear@1	2042 return samples;
nuclear@1	2043
nuclear@1	2044 }
nuclear@1	2045 }
nuclear@1	2046
nuclear@1	2047 /* suck in another packet */
nuclear@1	2048 {
nuclear@1	2049 int ret=_fetch_and_process_packet(vf,NULL,1,1);
nuclear@1	2050 if(ret==OV_EOF)return(0);
nuclear@1	2051 if(ret<=0)return(ret);
nuclear@1	2052 }
nuclear@1	2053
nuclear@1	2054 }
nuclear@1	2055 }
nuclear@1	2056
nuclear@1	2057 extern float vorbis_window(vorbis_dsp_state v,int W);
nuclear@1	2058
nuclear@1	2059 static void _ov_splice(float pcm,float lappcm,
nuclear@1	2060 int n1, int n2,
nuclear@1	2061 int ch1, int ch2,
nuclear@1	2062 float w1, float w2){
nuclear@1	2063 int i,j;
nuclear@1	2064 float *w=w1;
nuclear@1	2065 int n=n1;
nuclear@1	2066
nuclear@1	2067 if(n1>n2){
nuclear@1	2068 n=n2;
nuclear@1	2069 w=w2;
nuclear@1	2070 }
nuclear@1	2071
nuclear@1	2072 /* splice */
nuclear@1	2073 for(j=0;j<ch1 && j<ch2;j++){
nuclear@1	2074 float *s=lappcm[j];
nuclear@1	2075 float *d=pcm[j];
nuclear@1	2076
nuclear@1	2077 for(i=0;i<n;i++){
nuclear@1	2078 float wd=w[i]*w[i];
nuclear@1	2079 float ws=1.-wd;
nuclear@1	2080 d[i]=d[i]wd + s[i]ws;
nuclear@1	2081 }
nuclear@1	2082 }
nuclear@1	2083 /* window from zero */
nuclear@1	2084 for(;j<ch2;j++){
nuclear@1	2085 float *d=pcm[j];
nuclear@1	2086 for(i=0;i<n;i++){
nuclear@1	2087 float wd=w[i]*w[i];
nuclear@1	2088 d[i]=d[i]*wd;
nuclear@1	2089 }
nuclear@1	2090 }
nuclear@1	2091
nuclear@1	2092 }
nuclear@1	2093
nuclear@1	2094 /* make sure vf is INITSET */
nuclear@1	2095 static int _ov_initset(OggVorbis_File *vf){
nuclear@1	2096 while(1){
nuclear@1	2097 if(vf->ready_state==INITSET)break;
nuclear@1	2098 /* suck in another packet */
nuclear@1	2099 {
nuclear@1	2100 int ret=_fetch_and_process_packet(vf,NULL,1,0);
nuclear@1	2101 if(ret<0 && ret!=OV_HOLE)return(ret);
nuclear@1	2102 }
nuclear@1	2103 }
nuclear@1	2104 return 0;
nuclear@1	2105 }
nuclear@1	2106
nuclear@1	2107 /* make sure vf is INITSET and that we have a primed buffer; if
nuclear@1	2108 we're crosslapping at a stream section boundary, this also makes
nuclear@1	2109 sure we're sanity checking against the right stream information */
nuclear@1	2110 static int _ov_initprime(OggVorbis_File *vf){
nuclear@1	2111 vorbis_dsp_state *vd=&vf->vd;
nuclear@1	2112 while(1){
nuclear@1	2113 if(vf->ready_state==INITSET)
nuclear@1	2114 if(vorbis_synthesis_pcmout(vd,NULL))break;
nuclear@1	2115
nuclear@1	2116 /* suck in another packet */
nuclear@1	2117 {
nuclear@1	2118 int ret=_fetch_and_process_packet(vf,NULL,1,0);
nuclear@1	2119 if(ret<0 && ret!=OV_HOLE)return(ret);
nuclear@1	2120 }
nuclear@1	2121 }
nuclear@1	2122 return 0;
nuclear@1	2123 }
nuclear@1	2124
nuclear@1	2125 /* grab enough data for lapping from vf; this may be in the form of
nuclear@1	2126 unreturned, already-decoded pcm, remaining PCM we will need to
nuclear@1	2127 decode, or synthetic postextrapolation from last packets. */
nuclear@1	2128 static void _ov_getlap(OggVorbis_File vf,vorbis_info vi,vorbis_dsp_state *vd,
nuclear@1	2129 float **lappcm,int lapsize){
nuclear@1	2130 int lapcount=0,i;
nuclear@1	2131 float **pcm;
nuclear@1	2132
nuclear@1	2133 /* try first to decode the lapping data */
nuclear@1	2134 while(lapcount<lapsize){
nuclear@1	2135 int samples=vorbis_synthesis_pcmout(vd,&pcm);
nuclear@1	2136 if(samples){
nuclear@1	2137 if(samples>lapsize-lapcount)samples=lapsize-lapcount;
nuclear@1	2138 for(i=0;i<vi->channels;i++)
nuclear@1	2139 memcpy(lappcm[i]+lapcount,pcm[i],sizeof(*pcm)samples);
nuclear@1	2140 lapcount+=samples;
nuclear@1	2141 vorbis_synthesis_read(vd,samples);
nuclear@1	2142 }else{
nuclear@1	2143 /* suck in another packet */
nuclear@1	2144 int ret=_fetch_and_process_packet(vf,NULL,1,0); /* do not span */
nuclear@1	2145 if(ret==OV_EOF)break;
nuclear@1	2146 }
nuclear@1	2147 }
nuclear@1	2148 if(lapcount<lapsize){
nuclear@1	2149 /* failed to get lapping data from normal decode; pry it from the
nuclear@1	2150 postextrapolation buffering, or the second half of the MDCT
nuclear@1	2151 from the last packet */
nuclear@1	2152 int samples=vorbis_synthesis_lapout(&vf->vd,&pcm);
nuclear@1	2153 if(samples==0){
nuclear@1	2154 for(i=0;i<vi->channels;i++)
nuclear@1	2155 memset(lappcm[i]+lapcount,0,sizeof(*pcm)lapsize-lapcount);
nuclear@1	2156 lapcount=lapsize;
nuclear@1	2157 }else{
nuclear@1	2158 if(samples>lapsize-lapcount)samples=lapsize-lapcount;
nuclear@1	2159 for(i=0;i<vi->channels;i++)
nuclear@1	2160 memcpy(lappcm[i]+lapcount,pcm[i],sizeof(*pcm)samples);
nuclear@1	2161 lapcount+=samples;
nuclear@1	2162 }
nuclear@1	2163 }
nuclear@1	2164 }
nuclear@1	2165
nuclear@1	2166 /* this sets up crosslapping of a sample by using trailing data from
nuclear@1	2167 sample 1 and lapping it into the windowing buffer of sample 2 */
nuclear@1	2168 int ov_crosslap(OggVorbis_File vf1, OggVorbis_File vf2){
nuclear@1	2169 vorbis_info vi1,vi2;
nuclear@1	2170 float **lappcm;
nuclear@1	2171 float **pcm;
nuclear@1	2172 float w1,w2;
nuclear@1	2173 int n1,n2,i,ret,hs1,hs2;
nuclear@1	2174
nuclear@1	2175 if(vf1==vf2)return(0); /* degenerate case */
nuclear@1	2176 if(vf1->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	2177 if(vf2->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	2178
nuclear@1	2179 /* the relevant overlap buffers must be pre-checked and pre-primed
nuclear@1	2180 before looking at settings in the event that priming would cross
nuclear@1	2181 a bitstream boundary. So, do it now */
nuclear@1	2182
nuclear@1	2183 ret=_ov_initset(vf1);
nuclear@1	2184 if(ret)return(ret);
nuclear@1	2185 ret=_ov_initprime(vf2);
nuclear@1	2186 if(ret)return(ret);
nuclear@1	2187
nuclear@1	2188 vi1=ov_info(vf1,-1);
nuclear@1	2189 vi2=ov_info(vf2,-1);
nuclear@1	2190 hs1=ov_halfrate_p(vf1);
nuclear@1	2191 hs2=ov_halfrate_p(vf2);
nuclear@1	2192
nuclear@1	2193 lappcm=alloca(sizeof(lappcm)vi1->channels);
nuclear@1	2194 n1=vorbis_info_blocksize(vi1,0)>>(1+hs1);
nuclear@1	2195 n2=vorbis_info_blocksize(vi2,0)>>(1+hs2);
nuclear@1	2196 w1=vorbis_window(&vf1->vd,0);
nuclear@1	2197 w2=vorbis_window(&vf2->vd,0);
nuclear@1	2198
nuclear@1	2199 for(i=0;i<vi1->channels;i++)
nuclear@1	2200 lappcm[i]=alloca(sizeof(*lappcm)n1);
nuclear@1	2201
nuclear@1	2202 _ov_getlap(vf1,vi1,&vf1->vd,lappcm,n1);
nuclear@1	2203
nuclear@1	2204 /* have a lapping buffer from vf1; now to splice it into the lapping
nuclear@1	2205 buffer of vf2 */
nuclear@1	2206 /* consolidate and expose the buffer. */
nuclear@1	2207 vorbis_synthesis_lapout(&vf2->vd,&pcm);
nuclear@1	2208
nuclear@1	2209 #if 0
nuclear@1	2210 _analysis_output_always("pcmL",0,pcm[0],n1*2,0,0,0);
nuclear@1	2211 _analysis_output_always("pcmR",0,pcm[1],n1*2,0,0,0);
nuclear@1	2212 #endif
nuclear@1	2213
nuclear@1	2214 /* splice */
nuclear@1	2215 _ov_splice(pcm,lappcm,n1,n2,vi1->channels,vi2->channels,w1,w2);
nuclear@1	2216
nuclear@1	2217 /* done */
nuclear@1	2218 return(0);
nuclear@1	2219 }
nuclear@1	2220
nuclear@1	2221 static int _ov_64_seek_lap(OggVorbis_File *vf,ogg_int64_t pos,
nuclear@1	2222 int (localseek)(OggVorbis_File ,ogg_int64_t)){
nuclear@1	2223 vorbis_info *vi;
nuclear@1	2224 float **lappcm;
nuclear@1	2225 float **pcm;
nuclear@1	2226 float w1,w2;
nuclear@1	2227 int n1,n2,ch1,ch2,hs;
nuclear@1	2228 int i,ret;
nuclear@1	2229
nuclear@1	2230 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	2231 ret=_ov_initset(vf);
nuclear@1	2232 if(ret)return(ret);
nuclear@1	2233 vi=ov_info(vf,-1);
nuclear@1	2234 hs=ov_halfrate_p(vf);
nuclear@1	2235
nuclear@1	2236 ch1=vi->channels;
nuclear@1	2237 n1=vorbis_info_blocksize(vi,0)>>(1+hs);
nuclear@1	2238 w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are
nuclear@1	2239 persistent; even if the decode state
nuclear@1	2240 from this link gets dumped, this
nuclear@1	2241 window array continues to exist */
nuclear@1	2242
nuclear@1	2243 lappcm=alloca(sizeof(lappcm)ch1);
nuclear@1	2244 for(i=0;i<ch1;i++)
nuclear@1	2245 lappcm[i]=alloca(sizeof(*lappcm)n1);
nuclear@1	2246 _ov_getlap(vf,vi,&vf->vd,lappcm,n1);
nuclear@1	2247
nuclear@1	2248 /* have lapping data; seek and prime the buffer */
nuclear@1	2249 ret=localseek(vf,pos);
nuclear@1	2250 if(ret)return ret;
nuclear@1	2251 ret=_ov_initprime(vf);
nuclear@1	2252 if(ret)return(ret);
nuclear@1	2253
nuclear@1	2254 /* Guard against cross-link changes; they're perfectly legal */
nuclear@1	2255 vi=ov_info(vf,-1);
nuclear@1	2256 ch2=vi->channels;
nuclear@1	2257 n2=vorbis_info_blocksize(vi,0)>>(1+hs);
nuclear@1	2258 w2=vorbis_window(&vf->vd,0);
nuclear@1	2259
nuclear@1	2260 /* consolidate and expose the buffer. */
nuclear@1	2261 vorbis_synthesis_lapout(&vf->vd,&pcm);
nuclear@1	2262
nuclear@1	2263 /* splice */
nuclear@1	2264 _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2);
nuclear@1	2265
nuclear@1	2266 /* done */
nuclear@1	2267 return(0);
nuclear@1	2268 }
nuclear@1	2269
nuclear@1	2270 int ov_raw_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){
nuclear@1	2271 return _ov_64_seek_lap(vf,pos,ov_raw_seek);
nuclear@1	2272 }
nuclear@1	2273
nuclear@1	2274 int ov_pcm_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){
nuclear@1	2275 return _ov_64_seek_lap(vf,pos,ov_pcm_seek);
nuclear@1	2276 }
nuclear@1	2277
nuclear@1	2278 int ov_pcm_seek_page_lap(OggVorbis_File *vf,ogg_int64_t pos){
nuclear@1	2279 return _ov_64_seek_lap(vf,pos,ov_pcm_seek_page);
nuclear@1	2280 }
nuclear@1	2281
nuclear@1	2282 static int _ov_d_seek_lap(OggVorbis_File *vf,double pos,
nuclear@1	2283 int (localseek)(OggVorbis_File ,double)){
nuclear@1	2284 vorbis_info *vi;
nuclear@1	2285 float **lappcm;
nuclear@1	2286 float **pcm;
nuclear@1	2287 float w1,w2;
nuclear@1	2288 int n1,n2,ch1,ch2,hs;
nuclear@1	2289 int i,ret;
nuclear@1	2290
nuclear@1	2291 if(vf->ready_state<OPENED)return(OV_EINVAL);
nuclear@1	2292 ret=_ov_initset(vf);
nuclear@1	2293 if(ret)return(ret);
nuclear@1	2294 vi=ov_info(vf,-1);
nuclear@1	2295 hs=ov_halfrate_p(vf);
nuclear@1	2296
nuclear@1	2297 ch1=vi->channels;
nuclear@1	2298 n1=vorbis_info_blocksize(vi,0)>>(1+hs);
nuclear@1	2299 w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are
nuclear@1	2300 persistent; even if the decode state
nuclear@1	2301 from this link gets dumped, this
nuclear@1	2302 window array continues to exist */
nuclear@1	2303
nuclear@1	2304 lappcm=alloca(sizeof(lappcm)ch1);
nuclear@1	2305 for(i=0;i<ch1;i++)
nuclear@1	2306 lappcm[i]=alloca(sizeof(*lappcm)n1);
nuclear@1	2307 _ov_getlap(vf,vi,&vf->vd,lappcm,n1);
nuclear@1	2308
nuclear@1	2309 /* have lapping data; seek and prime the buffer */
nuclear@1	2310 ret=localseek(vf,pos);
nuclear@1	2311 if(ret)return ret;
nuclear@1	2312 ret=_ov_initprime(vf);
nuclear@1	2313 if(ret)return(ret);
nuclear@1	2314
nuclear@1	2315 /* Guard against cross-link changes; they're perfectly legal */
nuclear@1	2316 vi=ov_info(vf,-1);
nuclear@1	2317 ch2=vi->channels;
nuclear@1	2318 n2=vorbis_info_blocksize(vi,0)>>(1+hs);
nuclear@1	2319 w2=vorbis_window(&vf->vd,0);
nuclear@1	2320
nuclear@1	2321 /* consolidate and expose the buffer. */
nuclear@1	2322 vorbis_synthesis_lapout(&vf->vd,&pcm);
nuclear@1	2323
nuclear@1	2324 /* splice */
nuclear@1	2325 _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2);
nuclear@1	2326
nuclear@1	2327 /* done */
nuclear@1	2328 return(0);
nuclear@1	2329 }
nuclear@1	2330
nuclear@1	2331 int ov_time_seek_lap(OggVorbis_File *vf,double pos){
nuclear@1	2332 return _ov_d_seek_lap(vf,pos,ov_time_seek);
nuclear@1	2333 }
nuclear@1	2334
nuclear@1	2335 int ov_time_seek_page_lap(OggVorbis_File *vf,double pos){
nuclear@1	2336 return _ov_d_seek_lap(vf,pos,ov_time_seek_page);
nuclear@1	2337 }