diff options
Diffstat (limited to 'tremor/framing.c')
| -rw-r--r-- | tremor/framing.c | 900 |
1 files changed, 0 insertions, 900 deletions
diff --git a/tremor/framing.c b/tremor/framing.c deleted file mode 100644 index 17c28b1111..0000000000 --- a/tremor/framing.c +++ /dev/null @@ -1,900 +0,0 @@ -/******************************************************************** - * * - * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * - * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * - * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * - * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * - * * - * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2002 * - * by the Xiph.Org Foundation http://www.xiph.org/ * - * * - ******************************************************************** - - function: code raw [Vorbis] packets into framed OggSquish stream and - decode Ogg streams back into raw packets - last mod: $Id$ - - note: The CRC code is directly derived from public domain code by - Ross Williams (ross@guest.adelaide.edu.au). See docs/framing.html - for details. - - ********************************************************************/ - -#include <stdlib.h> -#include <string.h> -#include "ogg.h" - -/* A complete description of Ogg framing exists in docs/framing.html */ - -int ogg_page_version(ogg_page *og){ - return((int)(og->header[4])); -} - -int ogg_page_continued(ogg_page *og){ - return((int)(og->header[5]&0x01)); -} - -int ogg_page_bos(ogg_page *og){ - return((int)(og->header[5]&0x02)); -} - -int ogg_page_eos(ogg_page *og){ - return((int)(og->header[5]&0x04)); -} - -ogg_int64_t ogg_page_granulepos(ogg_page *og){ - unsigned char *page=og->header; - ogg_int64_t granulepos=page[13]&(0xff); - granulepos= (granulepos<<8)|(page[12]&0xff); - granulepos= (granulepos<<8)|(page[11]&0xff); - granulepos= (granulepos<<8)|(page[10]&0xff); - granulepos= (granulepos<<8)|(page[9]&0xff); - granulepos= (granulepos<<8)|(page[8]&0xff); - granulepos= (granulepos<<8)|(page[7]&0xff); - granulepos= (granulepos<<8)|(page[6]&0xff); - return(granulepos); -} - -int ogg_page_serialno(ogg_page *og){ - return(og->header[14] | - (og->header[15]<<8) | - (og->header[16]<<16) | - (og->header[17]<<24)); -} - -long ogg_page_pageno(ogg_page *og){ - return(og->header[18] | - (og->header[19]<<8) | - (og->header[20]<<16) | - (og->header[21]<<24)); -} - - - -/* returns the number of packets that are completed on this page (if - the leading packet is begun on a previous page, but ends on this - page, it's counted */ - -/* NOTE: -If a page consists of a packet begun on a previous page, and a new -packet begun (but not completed) on this page, the return will be: - ogg_page_packets(page) ==1, - ogg_page_continued(page) !=0 - -If a page happens to be a single packet that was begun on a -previous page, and spans to the next page (in the case of a three or -more page packet), the return will be: - ogg_page_packets(page) ==0, - ogg_page_continued(page) !=0 -*/ - -int ogg_page_packets(ogg_page *og){ - int i,n=og->header[26],count=0; - for(i=0;i<n;i++) - if(og->header[27+i]<255)count++; - return(count); -} - - -#if 0 -/* helper to initialize lookup for direct-table CRC (illustrative; we - use the static init below) */ - -static ogg_uint32_t _ogg_crc_entry(unsigned long index){ - int i; - unsigned long r; - - r = index << 24; - for (i=0; i<8; i++) - if (r & 0x80000000UL) - r = (r << 1) ^ 0x04c11db7; /* The same as the ethernet generator - polynomial, although we use an - unreflected alg and an init/final - of 0, not 0xffffffff */ - else - r<<=1; - return (r & 0xffffffffUL); -} -#endif - -static const ogg_uint32_t crc_lookup[256]={ - 0x00000000,0x04c11db7,0x09823b6e,0x0d4326d9, - 0x130476dc,0x17c56b6b,0x1a864db2,0x1e475005, - 0x2608edb8,0x22c9f00f,0x2f8ad6d6,0x2b4bcb61, - 0x350c9b64,0x31cd86d3,0x3c8ea00a,0x384fbdbd, - 0x4c11db70,0x48d0c6c7,0x4593e01e,0x4152fda9, - 0x5f15adac,0x5bd4b01b,0x569796c2,0x52568b75, - 0x6a1936c8,0x6ed82b7f,0x639b0da6,0x675a1011, - 0x791d4014,0x7ddc5da3,0x709f7b7a,0x745e66cd, - 0x9823b6e0,0x9ce2ab57,0x91a18d8e,0x95609039, - 0x8b27c03c,0x8fe6dd8b,0x82a5fb52,0x8664e6e5, - 0xbe2b5b58,0xbaea46ef,0xb7a96036,0xb3687d81, - 0xad2f2d84,0xa9ee3033,0xa4ad16ea,0xa06c0b5d, - 0xd4326d90,0xd0f37027,0xddb056fe,0xd9714b49, - 0xc7361b4c,0xc3f706fb,0xceb42022,0xca753d95, - 0xf23a8028,0xf6fb9d9f,0xfbb8bb46,0xff79a6f1, - 0xe13ef6f4,0xe5ffeb43,0xe8bccd9a,0xec7dd02d, - 0x34867077,0x30476dc0,0x3d044b19,0x39c556ae, - 0x278206ab,0x23431b1c,0x2e003dc5,0x2ac12072, - 0x128e9dcf,0x164f8078,0x1b0ca6a1,0x1fcdbb16, - 0x018aeb13,0x054bf6a4,0x0808d07d,0x0cc9cdca, - 0x7897ab07,0x7c56b6b0,0x71159069,0x75d48dde, - 0x6b93dddb,0x6f52c06c,0x6211e6b5,0x66d0fb02, - 0x5e9f46bf,0x5a5e5b08,0x571d7dd1,0x53dc6066, - 0x4d9b3063,0x495a2dd4,0x44190b0d,0x40d816ba, - 0xaca5c697,0xa864db20,0xa527fdf9,0xa1e6e04e, - 0xbfa1b04b,0xbb60adfc,0xb6238b25,0xb2e29692, - 0x8aad2b2f,0x8e6c3698,0x832f1041,0x87ee0df6, - 0x99a95df3,0x9d684044,0x902b669d,0x94ea7b2a, - 0xe0b41de7,0xe4750050,0xe9362689,0xedf73b3e, - 0xf3b06b3b,0xf771768c,0xfa325055,0xfef34de2, - 0xc6bcf05f,0xc27dede8,0xcf3ecb31,0xcbffd686, - 0xd5b88683,0xd1799b34,0xdc3abded,0xd8fba05a, - 0x690ce0ee,0x6dcdfd59,0x608edb80,0x644fc637, - 0x7a089632,0x7ec98b85,0x738aad5c,0x774bb0eb, - 0x4f040d56,0x4bc510e1,0x46863638,0x42472b8f, - 0x5c007b8a,0x58c1663d,0x558240e4,0x51435d53, - 0x251d3b9e,0x21dc2629,0x2c9f00f0,0x285e1d47, - 0x36194d42,0x32d850f5,0x3f9b762c,0x3b5a6b9b, - 0x0315d626,0x07d4cb91,0x0a97ed48,0x0e56f0ff, - 0x1011a0fa,0x14d0bd4d,0x19939b94,0x1d528623, - 0xf12f560e,0xf5ee4bb9,0xf8ad6d60,0xfc6c70d7, - 0xe22b20d2,0xe6ea3d65,0xeba91bbc,0xef68060b, - 0xd727bbb6,0xd3e6a601,0xdea580d8,0xda649d6f, - 0xc423cd6a,0xc0e2d0dd,0xcda1f604,0xc960ebb3, - 0xbd3e8d7e,0xb9ff90c9,0xb4bcb610,0xb07daba7, - 0xae3afba2,0xaafbe615,0xa7b8c0cc,0xa379dd7b, - 0x9b3660c6,0x9ff77d71,0x92b45ba8,0x9675461f, - 0x8832161a,0x8cf30bad,0x81b02d74,0x857130c3, - 0x5d8a9099,0x594b8d2e,0x5408abf7,0x50c9b640, - 0x4e8ee645,0x4a4ffbf2,0x470cdd2b,0x43cdc09c, - 0x7b827d21,0x7f436096,0x7200464f,0x76c15bf8, - 0x68860bfd,0x6c47164a,0x61043093,0x65c52d24, - 0x119b4be9,0x155a565e,0x18197087,0x1cd86d30, - 0x029f3d35,0x065e2082,0x0b1d065b,0x0fdc1bec, - 0x3793a651,0x3352bbe6,0x3e119d3f,0x3ad08088, - 0x2497d08d,0x2056cd3a,0x2d15ebe3,0x29d4f654, - 0xc5a92679,0xc1683bce,0xcc2b1d17,0xc8ea00a0, - 0xd6ad50a5,0xd26c4d12,0xdf2f6bcb,0xdbee767c, - 0xe3a1cbc1,0xe760d676,0xea23f0af,0xeee2ed18, - 0xf0a5bd1d,0xf464a0aa,0xf9278673,0xfde69bc4, - 0x89b8fd09,0x8d79e0be,0x803ac667,0x84fbdbd0, - 0x9abc8bd5,0x9e7d9662,0x933eb0bb,0x97ffad0c, - 0xafb010b1,0xab710d06,0xa6322bdf,0xa2f33668, - 0xbcb4666d,0xb8757bda,0xb5365d03,0xb1f740b4}; - -/* init the encode/decode logical stream state */ - -int ogg_stream_init(ogg_stream_state *os,int serialno){ - if(os){ - memset(os,0,sizeof(*os)); - os->body_storage=16*1024; - os->body_data=_ogg_malloc(os->body_storage*sizeof(*os->body_data)); - - os->lacing_storage=1024; - os->lacing_vals=_ogg_malloc(os->lacing_storage*sizeof(*os->lacing_vals)); - os->granule_vals=_ogg_malloc(os->lacing_storage*sizeof(*os->granule_vals)); - - os->serialno=serialno; - - return(0); - } - return(-1); -} - -/* _clear does not free os, only the non-flat storage within */ -int ogg_stream_clear(ogg_stream_state *os){ - if(os){ - if(os->body_data)_ogg_free(os->body_data); - if(os->lacing_vals)_ogg_free(os->lacing_vals); - if(os->granule_vals)_ogg_free(os->granule_vals); - - memset(os,0,sizeof(*os)); - } - return(0); -} - -int ogg_stream_destroy(ogg_stream_state *os){ - if(os){ - ogg_stream_clear(os); - _ogg_free(os); - } - return(0); -} - -/* Helpers for ogg_stream_encode; this keeps the structure and - what's happening fairly clear */ - -static void _os_body_expand(ogg_stream_state *os,int needed){ - if(os->body_storage<=os->body_fill+needed){ - os->body_storage+=(needed+1024); - os->body_data=_ogg_realloc(os->body_data,os->body_storage*sizeof(*os->body_data)); - } -} - -static void _os_lacing_expand(ogg_stream_state *os,int needed){ - if(os->lacing_storage<=os->lacing_fill+needed){ - os->lacing_storage+=(needed+32); - os->lacing_vals=_ogg_realloc(os->lacing_vals,os->lacing_storage*sizeof(*os->lacing_vals)); - os->granule_vals=_ogg_realloc(os->granule_vals,os->lacing_storage*sizeof(*os->granule_vals)); - } -} - -/* checksum the page */ -/* Direct table CRC; note that this will be faster in the future if we - perform the checksum silmultaneously with other copies */ - -void ogg_page_checksum_set(ogg_page *og){ - if(og){ - ogg_uint32_t crc_reg=0; - int i; - - /* safety; needed for API behavior, but not framing code */ - og->header[22]=0; - og->header[23]=0; - og->header[24]=0; - og->header[25]=0; - - for(i=0;i<og->header_len;i++) - crc_reg=(crc_reg<<8)^crc_lookup[((crc_reg >> 24)&0xff)^og->header[i]]; - for(i=0;i<og->body_len;i++) - crc_reg=(crc_reg<<8)^crc_lookup[((crc_reg >> 24)&0xff)^og->body[i]]; - - og->header[22]=(unsigned char)(crc_reg&0xff); - og->header[23]=(unsigned char)((crc_reg>>8)&0xff); - og->header[24]=(unsigned char)((crc_reg>>16)&0xff); - og->header[25]=(unsigned char)((crc_reg>>24)&0xff); - } -} - -/* submit data to the internal buffer of the framing engine */ -int ogg_stream_packetin(ogg_stream_state *os,ogg_packet *op){ - int lacing_vals=op->bytes/255+1,i; - - if(os->body_returned){ - /* advance packet data according to the body_returned pointer. We - had to keep it around to return a pointer into the buffer last - call */ - - os->body_fill-=os->body_returned; - if(os->body_fill) - memmove(os->body_data,os->body_data+os->body_returned, - os->body_fill); - os->body_returned=0; - } - - /* make sure we have the buffer storage */ - _os_body_expand(os,op->bytes); - _os_lacing_expand(os,lacing_vals); - - /* Copy in the submitted packet. Yes, the copy is a waste; this is - the liability of overly clean abstraction for the time being. It - will actually be fairly easy to eliminate the extra copy in the - future */ - - memcpy(os->body_data+os->body_fill,op->packet,op->bytes); - os->body_fill+=op->bytes; - - /* Store lacing vals for this packet */ - for(i=0;i<lacing_vals-1;i++){ - os->lacing_vals[os->lacing_fill+i]=255; - os->granule_vals[os->lacing_fill+i]=os->granulepos; - } - os->lacing_vals[os->lacing_fill+i]=(op->bytes)%255; - os->granulepos=os->granule_vals[os->lacing_fill+i]=op->granulepos; - - /* flag the first segment as the beginning of the packet */ - os->lacing_vals[os->lacing_fill]|= 0x100; - - os->lacing_fill+=lacing_vals; - - /* for the sake of completeness */ - os->packetno++; - - if(op->e_o_s)os->e_o_s=1; - - return(0); -} - -/* This will flush remaining packets into a page (returning nonzero), - even if there is not enough data to trigger a flush normally - (undersized page). If there are no packets or partial packets to - flush, ogg_stream_flush returns 0. Note that ogg_stream_flush will - try to flush a normal sized page like ogg_stream_pageout; a call to - ogg_stream_flush does not guarantee that all packets have flushed. - Only a return value of 0 from ogg_stream_flush indicates all packet - data is flushed into pages. - - since ogg_stream_flush will flush the last page in a stream even if - it's undersized, you almost certainly want to use ogg_stream_pageout - (and *not* ogg_stream_flush) unless you specifically need to flush - an page regardless of size in the middle of a stream. */ - -int ogg_stream_flush(ogg_stream_state *os,ogg_page *og){ - int i; - int vals=0; - int maxvals=(os->lacing_fill>255?255:os->lacing_fill); - int bytes=0; - long acc=0; - ogg_int64_t granule_pos=os->granule_vals[0]; - - if(maxvals==0)return(0); - - /* construct a page */ - /* decide how many segments to include */ - - /* If this is the initial header case, the first page must only include - the initial header packet */ - if(os->b_o_s==0){ /* 'initial header page' case */ - granule_pos=0; - for(vals=0;vals<maxvals;vals++){ - if((os->lacing_vals[vals]&0x0ff)<255){ - vals++; - break; - } - } - }else{ - for(vals=0;vals<maxvals;vals++){ - if(acc>4096)break; - acc+=os->lacing_vals[vals]&0x0ff; - granule_pos=os->granule_vals[vals]; - } - } - - /* construct the header in temp storage */ - memcpy(os->header,"OggS",4); - - /* stream structure version */ - os->header[4]=0x00; - - /* continued packet flag? */ - os->header[5]=0x00; - if((os->lacing_vals[0]&0x100)==0)os->header[5]|=0x01; - /* first page flag? */ - if(os->b_o_s==0)os->header[5]|=0x02; - /* last page flag? */ - if(os->e_o_s && os->lacing_fill==vals)os->header[5]|=0x04; - os->b_o_s=1; - - /* 64 bits of PCM position */ - for(i=6;i<14;i++){ - os->header[i]=(unsigned char)(granule_pos&0xff); - granule_pos>>=8; - } - - /* 32 bits of stream serial number */ - { - long serialno=os->serialno; - for(i=14;i<18;i++){ - os->header[i]=(unsigned char)(serialno&0xff); - serialno>>=8; - } - } - - /* 32 bits of page counter (we have both counter and page header - because this val can roll over) */ - if(os->pageno==-1)os->pageno=0; /* because someone called - stream_reset; this would be a - strange thing to do in an - encode stream, but it has - plausible uses */ - { - long pageno=os->pageno++; - for(i=18;i<22;i++){ - os->header[i]=(unsigned char)(pageno&0xff); - pageno>>=8; - } - } - - /* zero for computation; filled in later */ - os->header[22]=0; - os->header[23]=0; - os->header[24]=0; - os->header[25]=0; - - /* segment table */ - os->header[26]=(unsigned char)(vals&0xff); - for(i=0;i<vals;i++) - bytes+=os->header[i+27]=(unsigned char)(os->lacing_vals[i]&0xff); - - /* set pointers in the ogg_page struct */ - og->header=os->header; - og->header_len=os->header_fill=vals+27; - og->body=os->body_data+os->body_returned; - og->body_len=bytes; - - /* advance the lacing data and set the body_returned pointer */ - - os->lacing_fill-=vals; - memmove(os->lacing_vals,os->lacing_vals+vals,os->lacing_fill*sizeof(*os->lacing_vals)); - memmove(os->granule_vals,os->granule_vals+vals,os->lacing_fill*sizeof(*os->granule_vals)); - os->body_returned+=bytes; - - /* calculate the checksum */ - - ogg_page_checksum_set(og); - - /* done */ - return(1); -} - - -/* This constructs pages from buffered packet segments. The pointers -returned are to static buffers; do not free. The returned buffers are -good only until the next call (using the same ogg_stream_state) */ - -int ogg_stream_pageout(ogg_stream_state *os, ogg_page *og){ - - if((os->e_o_s&&os->lacing_fill) || /* 'were done, now flush' case */ - os->body_fill-os->body_returned > 4096 ||/* 'page nominal size' case */ - os->lacing_fill>=255 || /* 'segment table full' case */ - (os->lacing_fill&&!os->b_o_s)){ /* 'initial header page' case */ - - return(ogg_stream_flush(os,og)); - } - - /* not enough data to construct a page and not end of stream */ - return(0); -} - -int ogg_stream_eos(ogg_stream_state *os){ - return os->e_o_s; -} - -/* DECODING PRIMITIVES: packet streaming layer **********************/ - -/* This has two layers to place more of the multi-serialno and paging - control in the application's hands. First, we expose a data buffer - using ogg_sync_buffer(). The app either copies into the - buffer, or passes it directly to read(), etc. We then call - ogg_sync_wrote() to tell how many bytes we just added. - - Pages are returned (pointers into the buffer in ogg_sync_state) - by ogg_sync_pageout(). The page is then submitted to - ogg_stream_pagein() along with the appropriate - ogg_stream_state* (ie, matching serialno). We then get raw - packets out calling ogg_stream_packetout() with a - ogg_stream_state. See the 'frame-prog.txt' docs for details and - example code. */ - -/* initialize the struct to a known state */ -int ogg_sync_init(ogg_sync_state *oy){ - if(oy){ - memset(oy,0,sizeof(*oy)); - } - return(0); -} - -/* clear non-flat storage within */ -int ogg_sync_clear(ogg_sync_state *oy){ - if(oy){ - if(oy->data)_ogg_free(oy->data); - ogg_sync_init(oy); - } - return(0); -} - -int ogg_sync_destroy(ogg_sync_state *oy){ - if(oy){ - ogg_sync_clear(oy); - _ogg_free(oy); - } - return(0); -} - -char *ogg_sync_buffer(ogg_sync_state *oy, long size){ - - /* first, clear out any space that has been previously returned */ - if(oy->returned){ - oy->fill-=oy->returned; - if(oy->fill>0) - memmove(oy->data,oy->data+oy->returned,oy->fill); - oy->returned=0; - } - - if(size>oy->storage-oy->fill){ - /* We need to extend the internal buffer */ - long newsize=size+oy->fill+4096; /* an extra page to be nice */ - - if(oy->data) - oy->data=_ogg_realloc(oy->data,newsize); - else - oy->data=_ogg_malloc(newsize); - oy->storage=newsize; - } - - /* expose a segment at least as large as requested at the fill mark */ - return((char *)oy->data+oy->fill); -} - -int ogg_sync_wrote(ogg_sync_state *oy, long bytes){ - if(oy->fill+bytes>oy->storage)return(-1); - oy->fill+=bytes; - return(0); -} - -/* sync the stream. This is meant to be useful for finding page - boundaries. - - return values for this: - -n) skipped n bytes - 0) page not ready; more data (no bytes skipped) - n) page synced at current location; page length n bytes - -*/ - -long ogg_sync_pageseek(ogg_sync_state *oy,ogg_page *og){ - unsigned char *page=oy->data+oy->returned; - unsigned char *next; - long bytes=oy->fill-oy->returned; - - if(oy->headerbytes==0){ - int headerbytes,i; - if(bytes<27)return(0); /* not enough for a header */ - - /* verify capture pattern */ - if(memcmp(page,"OggS",4))goto sync_fail; - - headerbytes=page[26]+27; - if(bytes<headerbytes)return(0); /* not enough for header + seg table */ - - /* count up body length in the segment table */ - - for(i=0;i<page[26];i++) - oy->bodybytes+=page[27+i]; - oy->headerbytes=headerbytes; - } - - if(oy->bodybytes+oy->headerbytes>bytes)return(0); - - /* The whole test page is buffered. Verify the checksum */ - { - /* Grab the checksum bytes, set the header field to zero */ - char chksum[4]; - ogg_page log; - - memcpy(chksum,page+22,4); - memset(page+22,0,4); - - /* set up a temp page struct and recompute the checksum */ - log.header=page; - log.header_len=oy->headerbytes; - log.body=page+oy->headerbytes; - log.body_len=oy->bodybytes; - ogg_page_checksum_set(&log); - - /* Compare */ - if(memcmp(chksum,page+22,4)){ - /* D'oh. Mismatch! Corrupt page (or miscapture and not a page - at all) */ - /* replace the computed checksum with the one actually read in */ - memcpy(page+22,chksum,4); - - /* Bad checksum. Lose sync */ - goto sync_fail; - } - } - - /* yes, have a whole page all ready to go */ - { - unsigned char *page=oy->data+oy->returned; - long bytes; - - if(og){ - og->header=page; - og->header_len=oy->headerbytes; - og->body=page+oy->headerbytes; - og->body_len=oy->bodybytes; - } - - oy->unsynced=0; - oy->returned+=(bytes=oy->headerbytes+oy->bodybytes); - oy->headerbytes=0; - oy->bodybytes=0; - return(bytes); - } - - sync_fail: - - oy->headerbytes=0; - oy->bodybytes=0; - - /* search for possible capture */ - next=memchr(page+1,'O',bytes-1); - if(!next) - next=oy->data+oy->fill; - - oy->returned=next-oy->data; - return(-(next-page)); -} - -/* sync the stream and get a page. Keep trying until we find a page. - Suppress 'sync errors' after reporting the first. - - return values: - -1) recapture (hole in data) - 0) need more data - 1) page returned - - Returns pointers into buffered data; invalidated by next call to - _stream, _clear, _init, or _buffer */ - -int ogg_sync_pageout(ogg_sync_state *oy, ogg_page *og){ - - /* all we need to do is verify a page at the head of the stream - buffer. If it doesn't verify, we look for the next potential - frame */ - - for(;;){ - long ret=ogg_sync_pageseek(oy,og); - if(ret>0){ - /* have a page */ - return(1); - } - if(ret==0){ - /* need more data */ - return(0); - } - - /* head did not start a synced page... skipped some bytes */ - if(!oy->unsynced){ - oy->unsynced=1; - return(-1); - } - - /* loop. keep looking */ - - } -} - -/* add the incoming page to the stream state; we decompose the page - into packet segments here as well. */ - -int ogg_stream_pagein(ogg_stream_state *os, ogg_page *og){ - unsigned char *header=og->header; - unsigned char *body=og->body; - long bodysize=og->body_len; - int segptr=0; - - int version=ogg_page_version(og); - int continued=ogg_page_continued(og); - int bos=ogg_page_bos(og); - int eos=ogg_page_eos(og); - ogg_int64_t granulepos=ogg_page_granulepos(og); - int serialno=ogg_page_serialno(og); - long pageno=ogg_page_pageno(og); - int segments=header[26]; - - /* clean up 'returned data' */ - { - long lr=os->lacing_returned; - long br=os->body_returned; - - /* body data */ - if(br){ - os->body_fill-=br; - if(os->body_fill) - memmove(os->body_data,os->body_data+br,os->body_fill); - os->body_returned=0; - } - - if(lr){ - /* segment table */ - if(os->lacing_fill-lr){ - memmove(os->lacing_vals,os->lacing_vals+lr, - (os->lacing_fill-lr)*sizeof(*os->lacing_vals)); - memmove(os->granule_vals,os->granule_vals+lr, - (os->lacing_fill-lr)*sizeof(*os->granule_vals)); - } - os->lacing_fill-=lr; - os->lacing_packet-=lr; - os->lacing_returned=0; - } - } - - /* check the serial number */ - if(serialno!=os->serialno)return(-1); - if(version>0)return(-1); - - _os_lacing_expand(os,segments+1); - - /* are we in sequence? */ - if(pageno!=os->pageno){ - int i; - - /* unroll previous partial packet (if any) */ - for(i=os->lacing_packet;i<os->lacing_fill;i++) - os->body_fill-=os->lacing_vals[i]&0xff; - os->lacing_fill=os->lacing_packet; - - /* make a note of dropped data in segment table */ - if(os->pageno!=-1){ - os->lacing_vals[os->lacing_fill++]=0x400; - os->lacing_packet++; - } - } - - /* are we a 'continued packet' page? If so, we may need to skip - some segments */ - if(continued){ - if(os->lacing_fill<1 || - os->lacing_vals[os->lacing_fill-1]==0x400){ - bos=0; - for(;segptr<segments;segptr++){ - int val=header[27+segptr]; - body+=val; - bodysize-=val; - if(val<255){ - segptr++; - break; - } - } - } - } - - if(bodysize){ - _os_body_expand(os,bodysize); - memcpy(os->body_data+os->body_fill,body,bodysize); - os->body_fill+=bodysize; - } - - { - int saved=-1; - while(segptr<segments){ - int val=header[27+segptr]; - os->lacing_vals[os->lacing_fill]=val; - os->granule_vals[os->lacing_fill]=-1; - - if(bos){ - os->lacing_vals[os->lacing_fill]|=0x100; - bos=0; - } - - if(val<255)saved=os->lacing_fill; - - os->lacing_fill++; - segptr++; - - if(val<255)os->lacing_packet=os->lacing_fill; - } - - /* set the granulepos on the last granuleval of the last full packet */ - if(saved!=-1){ - os->granule_vals[saved]=granulepos; - } - - } - - if(eos){ - os->e_o_s=1; - if(os->lacing_fill>0) - os->lacing_vals[os->lacing_fill-1]|=0x200; - } - - os->pageno=pageno+1; - - return(0); -} - -/* clear things to an initial state. Good to call, eg, before seeking */ -int ogg_sync_reset(ogg_sync_state *oy){ - oy->fill=0; - oy->returned=0; - oy->unsynced=0; - oy->headerbytes=0; - oy->bodybytes=0; - return(0); -} - -int ogg_stream_reset(ogg_stream_state *os){ - os->body_fill=0; - os->body_returned=0; - - os->lacing_fill=0; - os->lacing_packet=0; - os->lacing_returned=0; - - os->header_fill=0; - - os->e_o_s=0; - os->b_o_s=0; - os->pageno=-1; - os->packetno=0; - os->granulepos=0; - - return(0); -} - -int ogg_stream_reset_serialno(ogg_stream_state *os,int serialno){ - ogg_stream_reset(os); - os->serialno=serialno; - return(0); -} - -static int _packetout(ogg_stream_state *os,ogg_packet *op,int adv){ - - /* The last part of decode. We have the stream broken into packet - segments. Now we need to group them into packets (or return the - out of sync markers) */ - - int ptr=os->lacing_returned; - - if(os->lacing_packet<=ptr)return(0); - - if(os->lacing_vals[ptr]&0x400){ - /* we need to tell the codec there's a gap; it might need to - handle previous packet dependencies. */ - os->lacing_returned++; - os->packetno++; - return(-1); - } - - if(!op && !adv)return(1); /* just using peek as an inexpensive way - to ask if there's a whole packet - waiting */ - - /* Gather the whole packet. We'll have no holes or a partial packet */ - { - int size=os->lacing_vals[ptr]&0xff; - int bytes=size; - int eos=os->lacing_vals[ptr]&0x200; /* last packet of the stream? */ - int bos=os->lacing_vals[ptr]&0x100; /* first packet of the stream? */ - - while(size==255){ - int val=os->lacing_vals[++ptr]; - size=val&0xff; - if(val&0x200)eos=0x200; - bytes+=size; - } - - if(op){ - op->e_o_s=eos; - op->b_o_s=bos; - op->packet=os->body_data+os->body_returned; - op->packetno=os->packetno; - op->granulepos=os->granule_vals[ptr]; - op->bytes=bytes; - } - - if(adv){ - os->body_returned+=bytes; - os->lacing_returned=ptr+1; - os->packetno++; - } - } - return(1); -} - -int ogg_stream_packetout(ogg_stream_state *os,ogg_packet *op){ - return _packetout(os,op,1); -} - -int ogg_stream_packetpeek(ogg_stream_state *os,ogg_packet *op){ - return _packetout(os,op,0); -} - -void ogg_packet_clear(ogg_packet *op) { - _ogg_free(op->packet); - memset(op, 0, sizeof(*op)); -} - |