1026 lines
29 KiB
C
1026 lines
29 KiB
C
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/********************************************************************
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* *
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* THIS FILE IS PART OF THE Ogg CONTAINER SOURCE CODE. *
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* USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
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* GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
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* IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
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* *
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* THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2010 *
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* by the Xiph.Org Foundation http://www.xiph.org/ *
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* *
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********************************************************************
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function: code raw packets into framed OggSquish stream and
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decode Ogg streams back into raw packets
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last mod: $Id: framing.c 18052 2011-08-04 17:57:02Z giles $
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note: The CRC code is directly derived from public domain code by
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Ross Williams (ross@guest.adelaide.edu.au). See docs/framing.html
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for details.
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********************************************************************/
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#include <stdlib.h>
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#include <string.h>
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#include <ogg/ogg.h>
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/* A complete description of Ogg framing exists in docs/framing.html */
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int ogg_page_version(const ogg_page *og){
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return((int)(og->header[4]));
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}
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int ogg_page_continued(const ogg_page *og){
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return((int)(og->header[5]&0x01));
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}
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int ogg_page_bos(const ogg_page *og){
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return((int)(og->header[5]&0x02));
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}
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int ogg_page_eos(const ogg_page *og){
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return((int)(og->header[5]&0x04));
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}
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ogg_int64_t ogg_page_granulepos(const ogg_page *og){
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unsigned char *page=og->header;
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ogg_int64_t granulepos=page[13]&(0xff);
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granulepos= (granulepos<<8)|(page[12]&0xff);
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granulepos= (granulepos<<8)|(page[11]&0xff);
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granulepos= (granulepos<<8)|(page[10]&0xff);
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granulepos= (granulepos<<8)|(page[9]&0xff);
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granulepos= (granulepos<<8)|(page[8]&0xff);
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granulepos= (granulepos<<8)|(page[7]&0xff);
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granulepos= (granulepos<<8)|(page[6]&0xff);
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return(granulepos);
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}
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int ogg_page_serialno(const ogg_page *og){
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return(og->header[14] |
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(og->header[15]<<8) |
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(og->header[16]<<16) |
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(og->header[17]<<24));
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}
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long ogg_page_pageno(const ogg_page *og){
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return(og->header[18] |
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(og->header[19]<<8) |
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(og->header[20]<<16) |
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(og->header[21]<<24));
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}
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/* returns the number of packets that are completed on this page (if
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the leading packet is begun on a previous page, but ends on this
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page, it's counted */
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/* NOTE:
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If a page consists of a packet begun on a previous page, and a new
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packet begun (but not completed) on this page, the return will be:
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ogg_page_packets(page) ==1,
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ogg_page_continued(page) !=0
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If a page happens to be a single packet that was begun on a
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previous page, and spans to the next page (in the case of a three or
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more page packet), the return will be:
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ogg_page_packets(page) ==0,
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ogg_page_continued(page) !=0
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*/
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int ogg_page_packets(const ogg_page *og){
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int i,n=og->header[26],count=0;
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for(i=0;i<n;i++)
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if(og->header[27+i]<255)count++;
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return(count);
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}
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#if 0
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/* helper to initialize lookup for direct-table CRC (illustrative; we
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use the static init below) */
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static ogg_uint32_t _ogg_crc_entry(unsigned long index){
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int i;
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unsigned long r;
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r = index << 24;
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for (i=0; i<8; i++)
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if (r & 0x80000000UL)
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r = (r << 1) ^ 0x04c11db7; /* The same as the ethernet generator
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polynomial, although we use an
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unreflected alg and an init/final
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of 0, not 0xffffffff */
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else
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r<<=1;
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return (r & 0xffffffffUL);
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}
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#endif
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static const ogg_uint32_t crc_lookup[256]={
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0x00000000,0x04c11db7,0x09823b6e,0x0d4326d9,
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0x130476dc,0x17c56b6b,0x1a864db2,0x1e475005,
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0x2608edb8,0x22c9f00f,0x2f8ad6d6,0x2b4bcb61,
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0x350c9b64,0x31cd86d3,0x3c8ea00a,0x384fbdbd,
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0x4c11db70,0x48d0c6c7,0x4593e01e,0x4152fda9,
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0x5f15adac,0x5bd4b01b,0x569796c2,0x52568b75,
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0x6a1936c8,0x6ed82b7f,0x639b0da6,0x675a1011,
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0x791d4014,0x7ddc5da3,0x709f7b7a,0x745e66cd,
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0x9823b6e0,0x9ce2ab57,0x91a18d8e,0x95609039,
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0x8b27c03c,0x8fe6dd8b,0x82a5fb52,0x8664e6e5,
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0xbe2b5b58,0xbaea46ef,0xb7a96036,0xb3687d81,
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0xad2f2d84,0xa9ee3033,0xa4ad16ea,0xa06c0b5d,
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0xd4326d90,0xd0f37027,0xddb056fe,0xd9714b49,
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0xc7361b4c,0xc3f706fb,0xceb42022,0xca753d95,
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0xf23a8028,0xf6fb9d9f,0xfbb8bb46,0xff79a6f1,
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0xe13ef6f4,0xe5ffeb43,0xe8bccd9a,0xec7dd02d,
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0x34867077,0x30476dc0,0x3d044b19,0x39c556ae,
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0x278206ab,0x23431b1c,0x2e003dc5,0x2ac12072,
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0x128e9dcf,0x164f8078,0x1b0ca6a1,0x1fcdbb16,
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0x018aeb13,0x054bf6a4,0x0808d07d,0x0cc9cdca,
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0x7897ab07,0x7c56b6b0,0x71159069,0x75d48dde,
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0x6b93dddb,0x6f52c06c,0x6211e6b5,0x66d0fb02,
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0x5e9f46bf,0x5a5e5b08,0x571d7dd1,0x53dc6066,
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0x4d9b3063,0x495a2dd4,0x44190b0d,0x40d816ba,
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0xaca5c697,0xa864db20,0xa527fdf9,0xa1e6e04e,
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0xbfa1b04b,0xbb60adfc,0xb6238b25,0xb2e29692,
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0x8aad2b2f,0x8e6c3698,0x832f1041,0x87ee0df6,
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0x99a95df3,0x9d684044,0x902b669d,0x94ea7b2a,
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0xe0b41de7,0xe4750050,0xe9362689,0xedf73b3e,
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0xf3b06b3b,0xf771768c,0xfa325055,0xfef34de2,
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0xc6bcf05f,0xc27dede8,0xcf3ecb31,0xcbffd686,
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0xd5b88683,0xd1799b34,0xdc3abded,0xd8fba05a,
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0x690ce0ee,0x6dcdfd59,0x608edb80,0x644fc637,
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0x7a089632,0x7ec98b85,0x738aad5c,0x774bb0eb,
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0x4f040d56,0x4bc510e1,0x46863638,0x42472b8f,
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0x5c007b8a,0x58c1663d,0x558240e4,0x51435d53,
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0x251d3b9e,0x21dc2629,0x2c9f00f0,0x285e1d47,
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0x36194d42,0x32d850f5,0x3f9b762c,0x3b5a6b9b,
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0x0315d626,0x07d4cb91,0x0a97ed48,0x0e56f0ff,
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0x1011a0fa,0x14d0bd4d,0x19939b94,0x1d528623,
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0xf12f560e,0xf5ee4bb9,0xf8ad6d60,0xfc6c70d7,
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0xe22b20d2,0xe6ea3d65,0xeba91bbc,0xef68060b,
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0xd727bbb6,0xd3e6a601,0xdea580d8,0xda649d6f,
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0xc423cd6a,0xc0e2d0dd,0xcda1f604,0xc960ebb3,
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0xbd3e8d7e,0xb9ff90c9,0xb4bcb610,0xb07daba7,
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0xae3afba2,0xaafbe615,0xa7b8c0cc,0xa379dd7b,
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0x9b3660c6,0x9ff77d71,0x92b45ba8,0x9675461f,
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0x8832161a,0x8cf30bad,0x81b02d74,0x857130c3,
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0x5d8a9099,0x594b8d2e,0x5408abf7,0x50c9b640,
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0x4e8ee645,0x4a4ffbf2,0x470cdd2b,0x43cdc09c,
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0x7b827d21,0x7f436096,0x7200464f,0x76c15bf8,
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0x68860bfd,0x6c47164a,0x61043093,0x65c52d24,
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0x119b4be9,0x155a565e,0x18197087,0x1cd86d30,
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0x029f3d35,0x065e2082,0x0b1d065b,0x0fdc1bec,
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0x3793a651,0x3352bbe6,0x3e119d3f,0x3ad08088,
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0x2497d08d,0x2056cd3a,0x2d15ebe3,0x29d4f654,
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0xc5a92679,0xc1683bce,0xcc2b1d17,0xc8ea00a0,
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0xd6ad50a5,0xd26c4d12,0xdf2f6bcb,0xdbee767c,
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0xe3a1cbc1,0xe760d676,0xea23f0af,0xeee2ed18,
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0xf0a5bd1d,0xf464a0aa,0xf9278673,0xfde69bc4,
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0x89b8fd09,0x8d79e0be,0x803ac667,0x84fbdbd0,
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0x9abc8bd5,0x9e7d9662,0x933eb0bb,0x97ffad0c,
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0xafb010b1,0xab710d06,0xa6322bdf,0xa2f33668,
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0xbcb4666d,0xb8757bda,0xb5365d03,0xb1f740b4};
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/* init the encode/decode logical stream state */
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int ogg_stream_init(ogg_stream_state *os,int serialno){
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if(os){
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memset(os,0,sizeof(*os));
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os->body_storage=16*1024;
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os->lacing_storage=1024;
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os->body_data=_ogg_malloc(os->body_storage*sizeof(*os->body_data));
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os->lacing_vals=_ogg_malloc(os->lacing_storage*sizeof(*os->lacing_vals));
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os->granule_vals=_ogg_malloc(os->lacing_storage*sizeof(*os->granule_vals));
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if(!os->body_data || !os->lacing_vals || !os->granule_vals){
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ogg_stream_clear(os);
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return -1;
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}
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os->serialno=serialno;
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return(0);
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}
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return(-1);
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}
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/* async/delayed error detection for the ogg_stream_state */
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int ogg_stream_check(ogg_stream_state *os){
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if(!os || !os->body_data) return -1;
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return 0;
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}
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/* _clear does not free os, only the non-flat storage within */
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int ogg_stream_clear(ogg_stream_state *os){
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if(os){
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if(os->body_data)_ogg_free(os->body_data);
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if(os->lacing_vals)_ogg_free(os->lacing_vals);
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if(os->granule_vals)_ogg_free(os->granule_vals);
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memset(os,0,sizeof(*os));
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}
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return(0);
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}
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int ogg_stream_destroy(ogg_stream_state *os){
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if(os){
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ogg_stream_clear(os);
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_ogg_free(os);
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}
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return(0);
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}
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/* Helpers for ogg_stream_encode; this keeps the structure and
|
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what's happening fairly clear */
|
||
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||
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static int _os_body_expand(ogg_stream_state *os,int needed){
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if(os->body_storage<=os->body_fill+needed){
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void *ret;
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ret=_ogg_realloc(os->body_data,(os->body_storage+needed+1024)*
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sizeof(*os->body_data));
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if(!ret){
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ogg_stream_clear(os);
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return -1;
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}
|
||
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os->body_storage+=(needed+1024);
|
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os->body_data=ret;
|
||
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}
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return 0;
|
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}
|
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||
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static int _os_lacing_expand(ogg_stream_state *os,int needed){
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if(os->lacing_storage<=os->lacing_fill+needed){
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void *ret;
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ret=_ogg_realloc(os->lacing_vals,(os->lacing_storage+needed+32)*
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sizeof(*os->lacing_vals));
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if(!ret){
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ogg_stream_clear(os);
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||
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return -1;
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|
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}
|
||
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os->lacing_vals=ret;
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||
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ret=_ogg_realloc(os->granule_vals,(os->lacing_storage+needed+32)*
|
||
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sizeof(*os->granule_vals));
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||
|
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if(!ret){
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ogg_stream_clear(os);
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||
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return -1;
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||
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}
|
||
|
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os->granule_vals=ret;
|
||
|
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os->lacing_storage+=(needed+32);
|
||
|
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}
|
||
|
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return 0;
|
||
|
|
}
|
||
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|
||
|
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/* checksum the page */
|
||
|
|
/* Direct table CRC; note that this will be faster in the future if we
|
||
|
|
perform the checksum simultaneously with other copies */
|
||
|
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|
||
|
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void ogg_page_checksum_set(ogg_page *og){
|
||
|
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if(og){
|
||
|
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ogg_uint32_t crc_reg=0;
|
||
|
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int i;
|
||
|
|
|
||
|
|
/* safety; needed for API behavior, but not framing code */
|
||
|
|
og->header[22]=0;
|
||
|
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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]];
|
||
|
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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_iovecin(ogg_stream_state *os, ogg_iovec_t *iov, int count,
|
||
|
|
long e_o_s, ogg_int64_t granulepos){
|
||
|
|
|
||
|
|
int bytes = 0, lacing_vals, i;
|
||
|
|
|
||
|
|
if(ogg_stream_check(os)) return -1;
|
||
|
|
if(!iov) return 0;
|
||
|
|
|
||
|
|
for (i = 0; i < count; ++i) bytes += (int)iov[i].iov_len;
|
||
|
|
lacing_vals=bytes/255+1;
|
||
|
|
|
||
|
|
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 */
|
||
|
|
if(_os_body_expand(os,bytes) || _os_lacing_expand(os,lacing_vals))
|
||
|
|
return -1;
|
||
|
|
|
||
|
|
/* 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 */
|
||
|
|
|
||
|
|
for (i = 0; i < count; ++i) {
|
||
|
|
memcpy(os->body_data+os->body_fill, iov[i].iov_base, iov[i].iov_len);
|
||
|
|
os->body_fill += (int)iov[i].iov_len;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* 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]=bytes%255;
|
||
|
|
os->granulepos=os->granule_vals[os->lacing_fill+i]=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(e_o_s)os->e_o_s=1;
|
||
|
|
|
||
|
|
return(0);
|
||
|
|
}
|
||
|
|
|
||
|
|
int ogg_stream_packetin(ogg_stream_state *os,ogg_packet *op){
|
||
|
|
ogg_iovec_t iov;
|
||
|
|
iov.iov_base = op->packet;
|
||
|
|
iov.iov_len = op->bytes;
|
||
|
|
return ogg_stream_iovecin(os, &iov, 1, op->e_o_s, op->granulepos);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Conditionally flush a page; force==0 will only flush nominal-size
|
||
|
|
pages, force==1 forces us to flush a page regardless of page size
|
||
|
|
so long as there's any data available at all. */
|
||
|
|
static int ogg_stream_flush_i(ogg_stream_state *os,ogg_page *og, int force, int nfill){
|
||
|
|
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=-1;
|
||
|
|
|
||
|
|
if(ogg_stream_check(os)) return(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{
|
||
|
|
|
||
|
|
/* The extra packets_done, packet_just_done logic here attempts to do two things:
|
||
|
|
1) Don't unneccessarily span pages.
|
||
|
|
2) Unless necessary, don't flush pages if there are less than four packets on
|
||
|
|
them; this expands page size to reduce unneccessary overhead if incoming packets
|
||
|
|
are large.
|
||
|
|
These are not necessary behaviors, just 'always better than naive flushing'
|
||
|
|
without requiring an application to explicitly request a specific optimized
|
||
|
|
behavior. We'll want an explicit behavior setup pathway eventually as well. */
|
||
|
|
|
||
|
|
int packets_done=0;
|
||
|
|
int packet_just_done=0;
|
||
|
|
for(vals=0;vals<maxvals;vals++){
|
||
|
|
if(acc>nfill && packet_just_done>=4){
|
||
|
|
force=1;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
acc+=os->lacing_vals[vals]&0x0ff;
|
||
|
|
if((os->lacing_vals[vals]&0xff)<255){
|
||
|
|
granule_pos=os->granule_vals[vals];
|
||
|
|
packet_just_done=++packets_done;
|
||
|
|
}else
|
||
|
|
packet_just_done=0;
|
||
|
|
}
|
||
|
|
if(vals==255)force=1;
|
||
|
|
}
|
||
|
|
|
||
|
|
if(!force) return(0);
|
||
|
|
|
||
|
|
/* 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 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
|
||
|
|
a page regardless of size in the middle of a stream. */
|
||
|
|
|
||
|
|
int ogg_stream_flush(ogg_stream_state *os,ogg_page *og){
|
||
|
|
return ogg_stream_flush_i(os,og,1,4096);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Like the above, but an argument is provided to adjust the nominal
|
||
|
|
page size for applications which are smart enough to provide their
|
||
|
|
own delay based flushing */
|
||
|
|
|
||
|
|
int ogg_stream_flush_fill(ogg_stream_state *os,ogg_page *og, int nfill){
|
||
|
|
return ogg_stream_flush_i(os,og,1,nfill);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* 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){
|
||
|
|
int force=0;
|
||
|
|
if(ogg_stream_check(os)) return 0;
|
||
|
|
|
||
|
|
if((os->e_o_s&&os->lacing_fill) || /* 'were done, now flush' case */
|
||
|
|
(os->lacing_fill&&!os->b_o_s)) /* 'initial header page' case */
|
||
|
|
force=1;
|
||
|
|
|
||
|
|
return(ogg_stream_flush_i(os,og,force,4096));
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Like the above, but an argument is provided to adjust the nominal
|
||
|
|
page size for applications which are smart enough to provide their
|
||
|
|
own delay based flushing */
|
||
|
|
|
||
|
|
int ogg_stream_pageout_fill(ogg_stream_state *os, ogg_page *og, int nfill){
|
||
|
|
int force=0;
|
||
|
|
if(ogg_stream_check(os)) return 0;
|
||
|
|
|
||
|
|
if((os->e_o_s&&os->lacing_fill) || /* 'were done, now flush' case */
|
||
|
|
(os->lacing_fill&&!os->b_o_s)) /* 'initial header page' case */
|
||
|
|
force=1;
|
||
|
|
|
||
|
|
return(ogg_stream_flush_i(os,og,force,nfill));
|
||
|
|
}
|
||
|
|
|
||
|
|
int ogg_stream_eos(ogg_stream_state *os){
|
||
|
|
if(ogg_stream_check(os)) return 1;
|
||
|
|
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. */
|
||
|
|
|
||
|
|
/* initialize the struct to a known state */
|
||
|
|
int ogg_sync_init(ogg_sync_state *oy){
|
||
|
|
if(oy){
|
||
|
|
oy->storage = -1; /* used as a readiness flag */
|
||
|
|
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);
|
||
|
|
memset(oy,0,sizeof(*oy));
|
||
|
|
}
|
||
|
|
return(0);
|
||
|
|
}
|
||
|
|
|
||
|
|
int ogg_sync_destroy(ogg_sync_state *oy){
|
||
|
|
if(oy){
|
||
|
|
ogg_sync_clear(oy);
|
||
|
|
_ogg_free(oy);
|
||
|
|
}
|
||
|
|
return(0);
|
||
|
|
}
|
||
|
|
|
||
|
|
int ogg_sync_check(ogg_sync_state *oy){
|
||
|
|
if(oy->storage<0) return -1;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
char *ogg_sync_buffer(ogg_sync_state *oy, long size){
|
||
|
|
if(ogg_sync_check(oy)) return NULL;
|
||
|
|
|
||
|
|
/* 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 */
|
||
|
|
void *ret;
|
||
|
|
|
||
|
|
if(oy->data)
|
||
|
|
ret=_ogg_realloc(oy->data,newsize);
|
||
|
|
else
|
||
|
|
ret=_ogg_malloc(newsize);
|
||
|
|
if(!ret){
|
||
|
|
ogg_sync_clear(oy);
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
oy->data=ret;
|
||
|
|
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(ogg_sync_check(oy))return -1;
|
||
|
|
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(ogg_sync_check(oy))return 0;
|
||
|
|
|
||
|
|
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 */
|
||
|
|
if (0) {
|
||
|
|
/* 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=(int)(next-oy->data);
|
||
|
|
return((long)-(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){
|
||
|
|
|
||
|
|
if(ogg_sync_check(oy))return 0;
|
||
|
|
|
||
|
|
/* 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];
|
||
|
|
|
||
|
|
if(ogg_stream_check(os)) return -1;
|
||
|
|
|
||
|
|
/* 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);
|
||
|
|
|
||
|
|
if(_os_lacing_expand(os,segments+1)) return -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){
|
||
|
|
if(_os_body_expand(os,bodysize)) return -1;
|
||
|
|
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){
|
||
|
|
if(ogg_sync_check(oy))return -1;
|
||
|
|
|
||
|
|
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){
|
||
|
|
if(ogg_stream_check(os)) return -1;
|
||
|
|
|
||
|
|
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){
|
||
|
|
if(ogg_stream_check(os)) return -1;
|
||
|
|
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;
|
||
|
|
long 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){
|
||
|
|
if(ogg_stream_check(os)) return 0;
|
||
|
|
return _packetout(os,op,1);
|
||
|
|
}
|
||
|
|
|
||
|
|
int ogg_stream_packetpeek(ogg_stream_state *os,ogg_packet *op){
|
||
|
|
if(ogg_stream_check(os)) return 0;
|
||
|
|
return _packetout(os,op,0);
|
||
|
|
}
|
||
|
|
|
||
|
|
void ogg_packet_clear(ogg_packet *op) {
|
||
|
|
_ogg_free(op->packet);
|
||
|
|
memset(op, 0, sizeof(*op));
|
||
|
|
}
|
||
|
|
|