/********************************************************************
 *                                                                  *
 * 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 1994-2007             *
 * by the Xiph.Org Foundation http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

 function: toplevel libogg include

 ********************************************************************/
#ifndef _OGG_H
#define _OGG_H

#ifdef __cplusplus
extern "C" {
#endif

#include <stddef.h>
#include "os_types.h"

extern const unsigned long mask[] ICONST_ATTR;

typedef struct {
  void *iov_base;
  size_t iov_len;
} ogg_iovec_t;

typedef struct {
  long endbyte;
  int  endbit;

  unsigned char *buffer;
  unsigned char *ptr;
  long storage;
} oggpack_buffer;

/* ogg_page is used to encapsulate the data in one Ogg bitstream page *****/

typedef struct {
  unsigned char *header;
  long header_len;
  unsigned char *body;
  long body_len;
} ogg_page;

/* ogg_stream_state contains the current encode/decode state of a logical
   Ogg bitstream **********************************************************/

typedef struct {
  unsigned char   *body_data;    /* bytes from packet bodies */
  long    body_storage;          /* storage elements allocated */
  long    body_fill;             /* elements stored; fill mark */
  long    body_returned;         /* elements of fill returned */


  int     *lacing_vals;      /* The values that will go to the segment table */
  ogg_int64_t *granule_vals; /* granulepos values for headers. Not compact
                                this way, but it is simple coupled to the
                                lacing fifo */
  long    lacing_storage;
  long    lacing_fill;
  long    lacing_packet;
  long    lacing_returned;

#if 0
  unsigned char    header[282];      /* working space for header encode */
  int              header_fill;
#endif
  int     e_o_s;          /* set when we have buffered the last packet in the
                             logical bitstream */
  int     b_o_s;          /* set after we've written the initial page
                             of a logical bitstream */
  ogg_uint32_t serialno;
  long    pageno;
  ogg_int64_t  packetno;  /* sequence number for decode; the framing
                             knows where there's a hole in the data,
                             but we need coupling so that the codec
                             (which is in a separate abstraction
                             layer) also knows about the gap */
  ogg_int64_t   granulepos;

} ogg_stream_state;

/* ogg_packet is used to encapsulate the data and metadata belonging
   to a single raw Ogg/Vorbis packet *************************************/

typedef struct {
  unsigned char *packet;
  long  bytes;
  long  b_o_s;
  long  e_o_s;

  ogg_int64_t  granulepos;

  ogg_int64_t  packetno;     /* sequence number for decode; the framing
                                knows where there's a hole in the data,
                                but we need coupling so that the codec
                                (which is in a separate abstraction
                                layer) also knows about the gap */
} ogg_packet;

typedef struct {
  unsigned char *data;
  int storage;
  int fill;
  int returned;

  int unsynced;
  int headerbytes;
  int bodybytes;
} ogg_sync_state;

/* Ogg BITSTREAM PRIMITIVES: bitstream ************************/
/*
extern void  oggpack_writeinit(oggpack_buffer *b);
extern int   oggpack_writecheck(oggpack_buffer *b);
extern void  oggpack_writetrunc(oggpack_buffer *b,long bits);
extern void  oggpack_writealign(oggpack_buffer *b);
extern void  oggpack_writecopy(oggpack_buffer *b,void *source,long bits);
extern void  oggpack_reset(oggpack_buffer *b);
extern void  oggpack_writeclear(oggpack_buffer *b); */
extern void  oggpack_readinit(oggpack_buffer *b,unsigned char *buf,int bytes);
/*
extern void  oggpack_write(oggpack_buffer *b,unsigned long value,int bits);
extern long  oggpack_look(oggpack_buffer *b,int bits);
*/

static inline long oggpack_look(oggpack_buffer *b,int bits){
  unsigned long ret;
  unsigned long m;

  if(bits<0 || bits>32) return -1;
  m=mask[bits];
  bits+=b->endbit;

  if(b->endbyte >= b->storage-4){
    /* not the main path */
    if(b->endbyte > b->storage-((bits+7)>>3)) return -1;
    /* special case to avoid reading b->ptr[0], which might be past the end of
        the buffer; also skips some useless accounting */
    else if(!bits)return(0L);
  }

  ret=b->ptr[0]>>b->endbit;
  if(bits>8){
    ret|=b->ptr[1]<<(8-b->endbit);  
    if(bits>16){
      ret|=b->ptr[2]<<(16-b->endbit);  
      if(bits>24){
        ret|=b->ptr[3]<<(24-b->endbit);  
        if(bits>32 && b->endbit)
          ret|=b->ptr[4]<<(32-b->endbit);
      }
    }
  }
  return(m&ret);
}
/*
extern long  oggpack_look1(oggpack_buffer *b);
extern void  oggpack_adv(oggpack_buffer *b,int bits);
*/

static inline void oggpack_adv(oggpack_buffer *b, unsigned int bits){
  bits+=b->endbit;

  if(b->endbyte > b->storage-(int)((bits+7)>>3)) goto overflow;

  b->ptr+=bits/8;
  b->endbyte+=bits/8;
  b->endbit=bits&7;
  return;

 overflow:
  b->ptr=NULL;
  b->endbyte=b->storage;
  b->endbit=1;
}

/*
extern void  oggpack_adv1(oggpack_buffer *b);
*/
extern long  oggpack_read(oggpack_buffer *b,int bits);
/*
extern long  oggpack_read1(oggpack_buffer *b);
extern long  oggpack_bytes(oggpack_buffer *b);
*/
static inline long oggpack_bytes(oggpack_buffer *b){
  return(b->endbyte+(b->endbit+7)/8);
}
#if 0
extern long  oggpack_bits(oggpack_buffer *b);
extern unsigned char *oggpack_get_buffer(oggpack_buffer *b);

extern void  oggpackB_writeinit(oggpack_buffer *b);
extern int   oggpackB_writecheck(oggpack_buffer *b);
extern void  oggpackB_writetrunc(oggpack_buffer *b,long bits);
extern void  oggpackB_writealign(oggpack_buffer *b);
extern void  oggpackB_writecopy(oggpack_buffer *b,void *source,long bits);
extern void  oggpackB_reset(oggpack_buffer *b);
extern void  oggpackB_writeclear(oggpack_buffer *b);
extern void  oggpackB_readinit(oggpack_buffer *b,unsigned char *buf,int bytes);
extern void  oggpackB_write(oggpack_buffer *b,unsigned long value,int bits);
extern long  oggpackB_look(oggpack_buffer *b,int bits);
extern long  oggpackB_look1(oggpack_buffer *b);
extern void  oggpackB_adv(oggpack_buffer *b,int bits);
extern void  oggpackB_adv1(oggpack_buffer *b);
extern long  oggpackB_read(oggpack_buffer *b,int bits);
extern long  oggpackB_read1(oggpack_buffer *b);
extern long  oggpackB_bytes(oggpack_buffer *b);
extern long  oggpackB_bits(oggpack_buffer *b);
extern unsigned char *oggpackB_get_buffer(oggpack_buffer *b);
# endif
/* Ogg BITSTREAM PRIMITIVES: encoding **************************/
#if 0
extern int      ogg_stream_packetin(ogg_stream_state *os, ogg_packet *op);
extern int      ogg_stream_iovecin(ogg_stream_state *os, ogg_iovec_t *iov,
                                   int count, long e_o_s, ogg_int64_t granulepos);
extern int      ogg_stream_pageout(ogg_stream_state *os, ogg_page *og);
extern int      ogg_stream_pageout_fill(ogg_stream_state *os, ogg_page *og, int nfill);
extern int      ogg_stream_flush(ogg_stream_state *os, ogg_page *og);
#endif
/* Ogg BITSTREAM PRIMITIVES: decoding **************************/

extern int      _os_body_expand(ogg_stream_state *os,int needed);

extern int      ogg_sync_init(ogg_sync_state *oy);
extern int      ogg_sync_clear(ogg_sync_state *oy);
extern int      ogg_sync_reset(ogg_sync_state *oy);
/*
extern int      ogg_sync_destroy(ogg_sync_state *oy);
extern int      ogg_sync_check(ogg_sync_state *oy);
*/

extern char    *ogg_sync_buffer(ogg_sync_state *oy, long size);
extern int      ogg_sync_wrote(ogg_sync_state *oy, long bytes);
extern long     ogg_sync_pageseek(ogg_sync_state *oy,ogg_page *og);
/*
extern int      ogg_sync_pageout(ogg_sync_state *oy, ogg_page *og);
*/
extern int      ogg_stream_pagein(ogg_stream_state *os, ogg_page *og, bool copy_body);
extern int      ogg_stream_packetout(ogg_stream_state *os,ogg_packet *op);
extern int      ogg_stream_packetpeek(ogg_stream_state *os,ogg_packet *op);

/* Ogg BITSTREAM PRIMITIVES: general ***************************/

extern int      ogg_stream_init(ogg_stream_state *os,int serialno);
extern int      ogg_stream_clear(ogg_stream_state *os);
extern int      ogg_stream_reset(ogg_stream_state *os);
extern int      ogg_stream_reset_serialno(ogg_stream_state *os,int serialno);
/*
extern int      ogg_stream_destroy(ogg_stream_state *os);
extern int      ogg_stream_check(ogg_stream_state *os);
*/
extern int      ogg_stream_eos(ogg_stream_state *os);

/*
extern void     ogg_page_checksum_set(ogg_page *og);
extern int      ogg_page_version(const ogg_page *og);
*/
extern int      ogg_page_continued(const ogg_page *og);
extern int      ogg_page_bos(const ogg_page *og);
extern int      ogg_page_eos(const ogg_page *og);
extern ogg_int64_t  ogg_page_granulepos(const ogg_page *og);
extern ogg_uint32_t ogg_page_serialno(const ogg_page *og);
/*
extern long     ogg_page_pageno(const ogg_page *og);
extern int      ogg_page_packets(const ogg_page *og);

extern void     ogg_packet_clear(ogg_packet *op);
*/

#ifdef __cplusplus
}
#endif

#endif  /* _OGG_H */