1 files changed, 909 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/libspeex/oggframing.c b/lib/rbcodec/codecs/libspeex/oggframing.c
new file mode 100644
index 0000000000..42d29502a8
--- /dev/null
+++ b/lib/rbcodec/codecs/libspeex/oggframing.c
@@ -0,0 +1,909 @@
+/********************************************************************
+ *                                                                  *
+ * 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 "config-tremor.h"
+#include <string.h>
+#include "speex/ogg.h"
+#include "arch.h"
+
+/* A complete description of Ogg framing exists in docs/framing.html */
+
+int spx_ogg_page_version(spx_ogg_page *og){
+  return((int)(og->header[4]));
+}
+
+int spx_ogg_page_continued(spx_ogg_page *og){
+  return((int)(og->header[5]&0x01));
+}
+
+int spx_ogg_page_bos(spx_ogg_page *og){
+  return((int)(og->header[5]&0x02));
+}
+
+int spx_ogg_page_eos(spx_ogg_page *og){
+  return((int)(og->header[5]&0x04));
+}
+
+spx_ogg_int64_t spx_ogg_page_granulepos(spx_ogg_page *og){
+  unsigned char *page=og->header;
+  spx_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 spx_ogg_page_serialno(spx_ogg_page *og){
+  return(og->header[14] |
+     (og->header[15]<<8) |
+     (og->header[16]<<16) |
+     (og->header[17]<<24));
+}
+ 
+long spx_ogg_page_pageno(spx_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:
+  spx_ogg_page_packets(page)   ==1, 
+  spx_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: 
+  spx_ogg_page_packets(page)   ==0, 
+  spx_ogg_page_continued(page) !=0
+*/
+
+int spx_ogg_page_packets(spx_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 spx_ogg_uint32_t _spx_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 spx_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 spx_ogg_stream_init(spx_ogg_stream_state *os,int serialno){
+  if(os){
+    memset(os,0,sizeof(*os));
+    os->body_storage=16*1024;
+    os->body_data=_spx_ogg_malloc(os->body_storage*sizeof(*os->body_data));
+
+    os->lacing_storage=1024;
+    os->lacing_vals=_spx_ogg_malloc(os->lacing_storage*sizeof(*os->lacing_vals));
+    os->granule_vals=_spx_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 spx_ogg_stream_clear(spx_ogg_stream_state *os){
+  if(os){
+    if(os->body_data)_spx_ogg_free(os->body_data);
+    if(os->lacing_vals)_spx_ogg_free(os->lacing_vals);
+    if(os->granule_vals)_spx_ogg_free(os->granule_vals);
+
+    memset(os,0,sizeof(*os));    
+  }
+  return(0);
+} 
+
+int spx_ogg_stream_destroy(spx_ogg_stream_state *os){
+  if(os){
+    spx_ogg_stream_clear(os);
+    _spx_ogg_free(os);
+  }
+  return(0);
+} 
+
+/* Helpers for spx_ogg_stream_encode; this keeps the structure and
+   what's happening fairly clear */
+
+static void _os_body_expand(spx_ogg_stream_state *os,int needed){
+  if(os->body_storage<=os->body_fill+needed){
+    os->body_storage+=(needed+1024);
+    os->body_data=_spx_ogg_realloc(os->body_data,os->body_storage*sizeof(*os->body_data));
+  }
+}
+
+static void _os_lacing_expand(spx_ogg_stream_state *os,int needed){
+  if(os->lacing_storage<=os->lacing_fill+needed){
+    os->lacing_storage+=(needed+32);
+    os->lacing_vals=_spx_ogg_realloc(os->lacing_vals,os->lacing_storage*sizeof(*os->lacing_vals));
+    os->granule_vals=_spx_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 spx_ogg_page_checksum_set(spx_ogg_page *og){
+  if(og){
+    spx_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 spx_ogg_stream_packetin(spx_ogg_stream_state *os,spx_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, spx_ogg_stream_flush returns 0.  Note that spx_ogg_stream_flush will
+   try to flush a normal sized page like spx_ogg_stream_pageout; a call to
+   spx_ogg_stream_flush does not guarantee that all packets have flushed.
+   Only a return value of 0 from spx_ogg_stream_flush indicates all packet
+   data is flushed into pages.
+
+   since spx_ogg_stream_flush will flush the last page in a stream even if
+   it's undersized, you almost certainly want to use spx_ogg_stream_pageout
+   (and *not* spx_ogg_stream_flush) unless you specifically need to flush 
+   an page regardless of size in the middle of a stream. */
+
+int spx_ogg_stream_flush(spx_ogg_stream_state *os,spx_ogg_page *og){
+  int i;
+  int vals=0;
+  int maxvals=(os->lacing_fill>255?255:os->lacing_fill);
+  int bytes=0;
+  long acc=0;
+  spx_ogg_int64_t granule_pos=-1;
+
+  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;
+      if((os->lacing_vals[vals]&0xff)<255)
+        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 spx_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 */
+  
+  spx_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 spx_ogg_stream_state) */
+
+int spx_ogg_stream_pageout(spx_ogg_stream_state *os, spx_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(spx_ogg_stream_flush(os,og));
+  }
+  
+  /* not enough data to construct a page and not end of stream */
+  return(0);
+}
+
+int spx_ogg_stream_eos(spx_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 spx_ogg_sync_buffer().  The app either copies into the
+   buffer, or passes it directly to read(), etc.  We then call
+   spx_ogg_sync_wrote() to tell how many bytes we just added.
+
+   Pages are returned (pointers into the buffer in spx_ogg_sync_state)
+   by spx_ogg_sync_pageout().  The page is then submitted to
+   spx_ogg_stream_pagein() along with the appropriate
+   spx_ogg_stream_state* (ie, matching serialno).  We then get raw
+   packets out calling spx_ogg_stream_packetout() with a
+   spx_ogg_stream_state. */
+
+/* initialize the struct to a known state */
+int spx_ogg_sync_init(spx_ogg_sync_state *oy){
+  if(oy){
+    memset(oy,0,sizeof(*oy));
+  }
+  return(0);
+}
+
+/* clear non-flat storage within */
+int spx_ogg_sync_clear(spx_ogg_sync_state *oy){
+  if(oy){
+    if(oy->data)_spx_ogg_free(oy->data);
+    spx_ogg_sync_init(oy);
+  }
+  return(0);
+}
+
+int spx_ogg_sync_destroy(spx_ogg_sync_state *oy){
+  if(oy){
+    spx_ogg_sync_clear(oy);
+    _spx_ogg_free(oy);
+  }
+  return(0);
+}
+void spx_ogg_alloc_buffer(spx_ogg_sync_state *oy, long size){
+    long newsize=size+oy->fill+size; /* an extra page to be nice */
+    if(oy->data){
+      oy->data=_spx_ogg_realloc(oy->data,newsize);
+    }else
+      oy->data=_spx_ogg_malloc(newsize);
+    oy->storage=newsize;
+    return;
+}
+
+char *spx_ogg_sync_buffer(spx_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=_spx_ogg_realloc(oy->data,newsize);
+    }else
+      oy->data=_spx_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 spx_ogg_sync_wrote(spx_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 spx_ogg_sync_pageseek(spx_ogg_sync_state *oy,spx_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];
+    spx_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;
+    spx_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.
+   Supress '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 spx_ogg_sync_pageout(spx_ogg_sync_state *oy, spx_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=spx_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 spx_ogg_stream_pagein(spx_ogg_stream_state *os, spx_ogg_page *og){
+  unsigned char *header=og->header;
+  unsigned char *body=og->body;
+  long           bodysize=og->body_len;
+  int            segptr=0;
+
+  int version=spx_ogg_page_version(og);
+  int continued=spx_ogg_page_continued(og);
+  int bos=spx_ogg_page_bos(og);
+  int eos=spx_ogg_page_eos(og);
+  spx_ogg_int64_t granulepos=spx_ogg_page_granulepos(og);
+  int serialno=spx_ogg_page_serialno(og);
+  long pageno=spx_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 spx_ogg_sync_reset(spx_ogg_sync_state *oy){
+  oy->fill=0;
+  oy->returned=0;
+  oy->unsynced=0;
+  oy->headerbytes=0;
+  oy->bodybytes=0;
+  return(0);
+}
+
+int spx_ogg_stream_reset(spx_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 spx_ogg_stream_reset_serialno(spx_ogg_stream_state *os,int serialno){
+  spx_ogg_stream_reset(os);
+  os->serialno=serialno;
+  return(0);
+}
+
+static int _packetout(spx_ogg_stream_state *os,spx_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 spx_ogg_stream_packetout(spx_ogg_stream_state *os,spx_ogg_packet *op){
+  return _packetout(os,op,1);
+}
+
+int spx_ogg_stream_packetpeek(spx_ogg_stream_state *os,spx_ogg_packet *op){
+  return _packetout(os,op,0);
+}
+
+void spx_ogg_packet_clear(spx_ogg_packet *op) {
+  _spx_ogg_free(op->packet);
+  memset(op, 0, sizeof(*op));
+}
+