aboutsummaryrefslogtreecommitdiffstats
path: root/Tremolo/framing.c
diff options
context:
space:
mode:
Diffstat (limited to 'Tremolo/framing.c')
-rw-r--r--Tremolo/framing.c1149
1 files changed, 0 insertions, 1149 deletions
diff --git a/Tremolo/framing.c b/Tremolo/framing.c
deleted file mode 100644
index 377269a..0000000
--- a/Tremolo/framing.c
+++ /dev/null
@@ -1,1149 +0,0 @@
-/********************************************************************
- * *
- * THIS FILE IS PART OF THE OggVorbis 'TREMOR' 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 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2003 *
- * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ *
- * *
- ********************************************************************
-
- function: decode Ogg streams back into raw packets
-
- 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"
-#include "misc.h"
-
-
-/* A complete description of Ogg framing exists in docs/framing.html */
-
-/* basic, centralized Ogg memory management based on linked lists of
- references to refcounted memory buffers. References and buffers
- are both recycled. Buffers are passed around and consumed in
- reference form. */
-
-static ogg_buffer_state *ogg_buffer_create(void){
- ogg_buffer_state *bs=_ogg_calloc(1,sizeof(*bs));
- return bs;
-}
-
-/* destruction is 'lazy'; there may be memory references outstanding,
- and yanking the buffer state out from underneath would be
- antisocial. Dealloc what is currently unused and have
- _release_one watch for the stragglers to come in. When they do,
- finish destruction. */
-
-/* call the helper while holding lock */
-static void _ogg_buffer_destroy(ogg_buffer_state *bs){
- ogg_buffer *bt;
- ogg_reference *rt;
-
- if(bs->shutdown){
-
- bt=bs->unused_buffers;
- rt=bs->unused_references;
-
- while(bt){
- ogg_buffer *b=bt;
- bt=b->ptr.next;
- if(b->data)_ogg_free(b->data);
- _ogg_free(b);
- }
- bs->unused_buffers=0;
- while(rt){
- ogg_reference *r=rt;
- rt=r->next;
- _ogg_free(r);
- }
- bs->unused_references=0;
-
- if(!bs->outstanding)
- _ogg_free(bs);
-
- }
-}
-
-static void ogg_buffer_destroy(ogg_buffer_state *bs){
- bs->shutdown=1;
- _ogg_buffer_destroy(bs);
-}
-
-static ogg_buffer *_fetch_buffer(ogg_buffer_state *bs,long bytes){
- ogg_buffer *ob;
- bs->outstanding++;
-
- /* do we have an unused buffer sitting in the pool? */
- if(bs->unused_buffers){
- ob=bs->unused_buffers;
- bs->unused_buffers=ob->ptr.next;
-
- /* if the unused buffer is too small, grow it */
- if(ob->size<bytes){
- ob->data=_ogg_realloc(ob->data,bytes);
- ob->size=bytes;
- }
- }else{
- /* allocate a new buffer */
- ob=_ogg_malloc(sizeof(*ob));
- ob->data=_ogg_malloc(bytes<16?16:bytes);
- ob->size=bytes;
- }
-
- ob->refcount=1;
- ob->ptr.owner=bs;
- return ob;
-}
-
-static ogg_reference *_fetch_ref(ogg_buffer_state *bs){
- ogg_reference *or;
- bs->outstanding++;
-
- /* do we have an unused reference sitting in the pool? */
- if(bs->unused_references){
- or=bs->unused_references;
- bs->unused_references=or->next;
- }else{
- /* allocate a new reference */
- or=_ogg_malloc(sizeof(*or));
- }
-
- or->begin=0;
- or->length=0;
- or->next=0;
- return or;
-}
-
-/* fetch a reference pointing to a fresh, initially continguous buffer
- of at least [bytes] length */
-static ogg_reference *ogg_buffer_alloc(ogg_buffer_state *bs,long bytes){
- ogg_buffer *ob=_fetch_buffer(bs,bytes);
- ogg_reference *or=_fetch_ref(bs);
- or->buffer=ob;
- return or;
-}
-
-/* enlarge the data buffer in the current link */
-static void ogg_buffer_realloc(ogg_reference *or,long bytes){
- ogg_buffer *ob=or->buffer;
-
- /* if the unused buffer is too small, grow it */
- if(ob->size<bytes){
- ob->data=_ogg_realloc(ob->data,bytes);
- ob->size=bytes;
- }
-}
-
-static void _ogg_buffer_mark_one(ogg_reference *or){
- or->buffer->refcount++;
-}
-
-/* increase the refcount of the buffers to which the reference points */
-static void ogg_buffer_mark(ogg_reference *or){
- while(or){
- _ogg_buffer_mark_one(or);
- or=or->next;
- }
-}
-
-/* duplicate a reference (pointing to the same actual buffer memory)
- and increment buffer refcount. If the desired segment is zero
- length, a zero length ref is returned. */
-static ogg_reference *ogg_buffer_sub(ogg_reference *or,long length){
- ogg_reference *ret=0,*head=0;
-
- /* duplicate the reference chain; increment refcounts */
- while(or && length){
- ogg_reference *temp=_fetch_ref(or->buffer->ptr.owner);
- if(head)
- head->next=temp;
- else
- ret=temp;
- head=temp;
- head->buffer=or->buffer;
- head->begin=or->begin;
- head->length=length;
- if(head->length>or->length)
- head->length=or->length;
-
- length-=head->length;
- or=or->next;
- }
-
- ogg_buffer_mark(ret);
- return ret;
-}
-
-ogg_reference *ogg_buffer_dup(ogg_reference *or){
- ogg_reference *ret=0,*head=0;
- /* duplicate the reference chain; increment refcounts */
- while(or){
- ogg_reference *temp=_fetch_ref(or->buffer->ptr.owner);
- if(head)
- head->next=temp;
- else
- ret=temp;
- head=temp;
- head->buffer=or->buffer;
- head->begin=or->begin;
- head->length=or->length;
- or=or->next;
- }
-
- ogg_buffer_mark(ret);
- return ret;
-}
-
-/* split a reference into two references; 'return' is a reference to
- the buffer preceeding pos and 'head'/'tail' are the buffer past the
- split. If pos is at or past the end of the passed in segment,
- 'head/tail' are NULL */
-static ogg_reference *ogg_buffer_split(ogg_reference **tail,
- ogg_reference **head,long pos){
-
- /* walk past any preceeding fragments to one of:
- a) the exact boundary that seps two fragments
- b) the fragment that needs split somewhere in the middle */
- ogg_reference *ret=*tail;
- ogg_reference *or=*tail;
-
- while(or && pos>or->length){
- pos-=or->length;
- or=or->next;
- }
-
- if(!or || pos==0){
-
- return 0;
-
- }else{
-
- if(pos>=or->length){
- /* exact split, or off the end? */
- if(or->next){
-
- /* a split */
- *tail=or->next;
- or->next=0;
-
- }else{
-
- /* off or at the end */
- *tail=*head=0;
-
- }
- }else{
-
- /* split within a fragment */
- long lengthA=pos;
- long beginB=or->begin+pos;
- long lengthB=or->length-pos;
-
- /* make a new reference to tail the second piece */
- *tail=_fetch_ref(or->buffer->ptr.owner);
-
- (*tail)->buffer=or->buffer;
- (*tail)->begin=beginB;
- (*tail)->length=lengthB;
- (*tail)->next=or->next;
- _ogg_buffer_mark_one(*tail);
- if(head && or==*head)*head=*tail;
-
- /* update the first piece */
- or->next=0;
- or->length=lengthA;
-
- }
- }
- return ret;
-}
-
-static void ogg_buffer_release_one(ogg_reference *or){
- ogg_buffer *ob=or->buffer;
- ogg_buffer_state *bs=ob->ptr.owner;
-
- ob->refcount--;
- if(ob->refcount==0){
- bs->outstanding--; /* for the returned buffer */
- ob->ptr.next=bs->unused_buffers;
- bs->unused_buffers=ob;
- }
-
- bs->outstanding--; /* for the returned reference */
- or->next=bs->unused_references;
- bs->unused_references=or;
-
- _ogg_buffer_destroy(bs); /* lazy cleanup (if needed) */
-
-}
-
-/* release the references, decrease the refcounts of buffers to which
- they point, release any buffers with a refcount that drops to zero */
-static void ogg_buffer_release(ogg_reference *or){
- while(or){
- ogg_reference *next=or->next;
- ogg_buffer_release_one(or);
- or=next;
- }
-}
-
-static ogg_reference *ogg_buffer_pretruncate(ogg_reference *or,long pos){
- /* release preceeding fragments we don't want */
- while(or && pos>=or->length){
- ogg_reference *next=or->next;
- pos-=or->length;
- ogg_buffer_release_one(or);
- or=next;
- }
- if (or) {
- or->begin+=pos;
- or->length-=pos;
- }
- return or;
-}
-
-static ogg_reference *ogg_buffer_walk(ogg_reference *or){
- if(!or)return NULL;
- while(or->next){
- or=or->next;
- }
- return(or);
-}
-
-/* *head is appended to the front end (head) of *tail; both continue to
- be valid pointers, with *tail at the tail and *head at the head */
-static ogg_reference *ogg_buffer_cat(ogg_reference *tail, ogg_reference *head){
- if(!tail)return head;
-
- while(tail->next){
- tail=tail->next;
- }
- tail->next=head;
- return ogg_buffer_walk(head);
-}
-
-static void _positionB(oggbyte_buffer *b,int pos){
- if(pos<b->pos){
- /* start at beginning, scan forward */
- b->ref=b->baseref;
- b->pos=0;
- b->end=b->pos+b->ref->length;
- b->ptr=b->ref->buffer->data+b->ref->begin;
- }
-}
-
-static void _positionF(oggbyte_buffer *b,int pos){
- /* scan forward for position */
- while(pos>=b->end){
- /* just seek forward */
- b->pos+=b->ref->length;
- b->ref=b->ref->next;
- b->end=b->ref->length+b->pos;
- b->ptr=b->ref->buffer->data+b->ref->begin;
- }
-}
-
-static int oggbyte_init(oggbyte_buffer *b,ogg_reference *or){
- memset(b,0,sizeof(*b));
- if(or){
- b->ref=b->baseref=or;
- b->pos=0;
- b->end=b->ref->length;
- b->ptr=b->ref->buffer->data+b->ref->begin;
- return 0;
- }else
- return -1;
-}
-
-static void oggbyte_set4(oggbyte_buffer *b,ogg_uint32_t val,int pos){
- int i;
- _positionB(b,pos);
- for(i=0;i<4;i++){
- _positionF(b,pos);
- b->ptr[pos-b->pos]=val;
- val>>=8;
- ++pos;
- }
-}
-
-static unsigned char oggbyte_read1(oggbyte_buffer *b,int pos){
- _positionB(b,pos);
- _positionF(b,pos);
- return b->ptr[pos-b->pos];
-}
-
-static ogg_uint32_t oggbyte_read4(oggbyte_buffer *b,int pos){
- ogg_uint32_t ret;
- _positionB(b,pos);
- _positionF(b,pos);
- ret=b->ptr[pos-b->pos];
- _positionF(b,++pos);
- ret|=b->ptr[pos-b->pos]<<8;
- _positionF(b,++pos);
- ret|=b->ptr[pos-b->pos]<<16;
- _positionF(b,++pos);
- ret|=b->ptr[pos-b->pos]<<24;
- return ret;
-}
-
-static ogg_int64_t oggbyte_read8(oggbyte_buffer *b,int pos){
- ogg_int64_t ret;
- unsigned char t[7];
- int i;
- _positionB(b,pos);
- for(i=0;i<7;i++){
- _positionF(b,pos);
- t[i]=b->ptr[pos++ -b->pos];
- }
-
- _positionF(b,pos);
- ret=b->ptr[pos-b->pos];
-
- for(i=6;i>=0;--i)
- ret= ret<<8 | t[i];
-
- return ret;
-}
-
-/* Now we get to the actual framing code */
-
-int ogg_page_version(ogg_page *og){
- oggbyte_buffer ob;
- if(oggbyte_init(&ob,og->header))return -1;
- return oggbyte_read1(&ob,4);
-}
-
-int ogg_page_continued(ogg_page *og){
- oggbyte_buffer ob;
- if(oggbyte_init(&ob,og->header))return -1;
- return oggbyte_read1(&ob,5)&0x01;
-}
-
-int ogg_page_bos(ogg_page *og){
- oggbyte_buffer ob;
- if(oggbyte_init(&ob,og->header))return -1;
- return oggbyte_read1(&ob,5)&0x02;
-}
-
-int ogg_page_eos(ogg_page *og){
- oggbyte_buffer ob;
- if(oggbyte_init(&ob,og->header))return -1;
- return oggbyte_read1(&ob,5)&0x04;
-}
-
-ogg_int64_t ogg_page_granulepos(ogg_page *og){
- oggbyte_buffer ob;
- if(oggbyte_init(&ob,og->header))return -1;
- return oggbyte_read8(&ob,6);
-}
-
-ogg_uint32_t ogg_page_serialno(ogg_page *og){
- oggbyte_buffer ob;
- if(oggbyte_init(&ob,og->header)) return 0xffffffffUL;
- return oggbyte_read4(&ob,14);
-}
-
-ogg_uint32_t ogg_page_pageno(ogg_page *og){
- oggbyte_buffer ob;
- if(oggbyte_init(&ob,og->header))return 0xffffffffUL;
- return oggbyte_read4(&ob,18);
-}
-
-/* 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;
- int n;
- int count=0;
- oggbyte_buffer ob;
- oggbyte_init(&ob,og->header);
-
- n=oggbyte_read1(&ob,26);
- for(i=0;i<n;i++)
- if(oggbyte_read1(&ob,27+i)<255)count++;
- return(count);
-}
-
-/* Static CRC calculation table. See older code in CVS for dead
- run-time initialization code. */
-
-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};
-
-void ogg_sync_init(ogg_sync_state *oy){
- memset(oy,0,sizeof(*oy));
- oy->bufferpool=ogg_buffer_create();
-}
-
-ogg_sync_state *ogg_sync_create(void){
- ogg_sync_state *oy=_ogg_calloc(1,sizeof(*oy));
- memset(oy,0,sizeof(*oy));
- oy->bufferpool=ogg_buffer_create();
- return oy;
-}
-
-int ogg_sync_clear(ogg_sync_state *oy){
- if(oy){
- ogg_sync_reset(oy);
- ogg_buffer_destroy(oy->bufferpool);
- memset(oy,0,sizeof(*oy));
- }
- return OGG_SUCCESS;
-}
-
-int ogg_sync_destroy(ogg_sync_state *oy){
- if(oy){
- ogg_sync_reset(oy);
- ogg_buffer_destroy(oy->bufferpool);
- memset(oy,0,sizeof(*oy));
- _ogg_free(oy);
- }
- return OGG_SUCCESS;
-}
-
-unsigned char *ogg_sync_bufferin(ogg_sync_state *oy, long bytes){
-
- /* [allocate and] expose a buffer for data submission.
-
- If there is no head fragment
- allocate one and expose it
- else
- if the current head fragment has sufficient unused space
- expose it
- else
- if the current head fragment is unused
- resize and expose it
- else
- allocate new fragment and expose it
- */
-
- /* base case; fifo uninitialized */
- if(!oy->fifo_head){
- oy->fifo_head=oy->fifo_tail=ogg_buffer_alloc(oy->bufferpool,bytes);
- return oy->fifo_head->buffer->data;
- }
-
- /* space left in current fragment case */
- if(oy->fifo_head->buffer->size-
- oy->fifo_head->length-
- oy->fifo_head->begin >= bytes)
- return oy->fifo_head->buffer->data+
- oy->fifo_head->length+oy->fifo_head->begin;
-
- /* current fragment is unused, but too small */
- if(!oy->fifo_head->length){
- ogg_buffer_realloc(oy->fifo_head,bytes);
- return oy->fifo_head->buffer->data+oy->fifo_head->begin;
- }
-
- /* current fragment used/full; get new fragment */
- {
- ogg_reference *new=ogg_buffer_alloc(oy->bufferpool,bytes);
- oy->fifo_head->next=new;
- oy->fifo_head=new;
- }
- return oy->fifo_head->buffer->data;
-}
-
-int ogg_sync_wrote(ogg_sync_state *oy, long bytes){
- if(!oy->fifo_head)return OGG_EINVAL;
- if(oy->fifo_head->buffer->size-oy->fifo_head->length-oy->fifo_head->begin <
- bytes)return OGG_EINVAL;
- oy->fifo_head->length+=bytes;
- oy->fifo_fill+=bytes;
- return OGG_SUCCESS;
-}
-
-#ifndef ONLY_C
-ogg_uint32_t _checksum(ogg_reference *or, int bytes);
-#else
-static ogg_uint32_t _checksum(ogg_reference *or, int bytes){
- ogg_uint32_t crc_reg=0;
- int j,post;
-
- while(or){
- unsigned char *data=or->buffer->data+or->begin;
- post=(bytes<or->length?bytes:or->length);
- for(j=0;j<post;++j)
- crc_reg=(crc_reg<<8)^crc_lookup[((crc_reg >> 24)&0xff)^data[j]];
- bytes-=j;
- or=or->next;
- }
-
- return crc_reg;
-}
-#endif
-
-/* 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){
- oggbyte_buffer page;
- long bytes,ret=0;
-
- ogg_page_release(og);
-
- bytes=oy->fifo_fill;
- oggbyte_init(&page,oy->fifo_tail);
-
- if(oy->headerbytes==0){
- if(bytes<27)goto sync_out; /* not enough for even a minimal header */
-
- /* verify capture pattern */
- if(oggbyte_read1(&page,0)!=(int)'O' ||
- oggbyte_read1(&page,1)!=(int)'g' ||
- oggbyte_read1(&page,2)!=(int)'g' ||
- oggbyte_read1(&page,3)!=(int)'S' ) goto sync_fail;
-
- oy->headerbytes=oggbyte_read1(&page,26)+27;
- }
- if(bytes<oy->headerbytes)goto sync_out; /* not enough for header +
- seg table */
- if(oy->bodybytes==0){
- int i;
- /* count up body length in the segment table */
- for(i=0;i<oy->headerbytes-27;i++)
- oy->bodybytes+=oggbyte_read1(&page,27+i);
- }
-
- if(oy->bodybytes+oy->headerbytes>bytes)goto sync_out;
-
- /* we have what appears to be a complete page; last test: verify
- checksum */
- {
- ogg_uint32_t chksum=oggbyte_read4(&page,22);
- oggbyte_set4(&page,0,22);
-
- /* Compare checksums; memory continues to be common access */
- if(chksum!=_checksum(oy->fifo_tail,oy->bodybytes+oy->headerbytes)){
-
- /* D'oh. Mismatch! Corrupt page (or miscapture and not a page
- at all). replace the computed checksum with the one actually
- read in; remember all the memory is common access */
-
- oggbyte_set4(&page,chksum,22);
- goto sync_fail;
- }
- oggbyte_set4(&page,chksum,22);
- }
-
- /* We have a page. Set up page return. */
- if(og){
- /* set up page output */
- og->header=ogg_buffer_split(&oy->fifo_tail,&oy->fifo_head,oy->headerbytes);
- og->header_len=oy->headerbytes;
- og->body=ogg_buffer_split(&oy->fifo_tail,&oy->fifo_head,oy->bodybytes);
- og->body_len=oy->bodybytes;
- }else{
- /* simply advance */
- oy->fifo_tail=
- ogg_buffer_pretruncate(oy->fifo_tail,oy->headerbytes+oy->bodybytes);
- if(!oy->fifo_tail)oy->fifo_head=0;
- }
-
- ret=oy->headerbytes+oy->bodybytes;
- oy->unsynced=0;
- oy->headerbytes=0;
- oy->bodybytes=0;
- oy->fifo_fill-=ret;
-
- return ret;
-
- sync_fail:
-
- oy->headerbytes=0;
- oy->bodybytes=0;
- oy->fifo_tail=ogg_buffer_pretruncate(oy->fifo_tail,1);
- ret--;
-
- /* search forward through fragments for possible capture */
- while(oy->fifo_tail){
- /* invariant: fifo_cursor points to a position in fifo_tail */
- unsigned char *now=oy->fifo_tail->buffer->data+oy->fifo_tail->begin;
- unsigned char *next=memchr(now, 'O', oy->fifo_tail->length);
-
- if(next){
- /* possible capture in this segment */
- long bytes=next-now;
- oy->fifo_tail=ogg_buffer_pretruncate(oy->fifo_tail,bytes);
- ret-=bytes;
- break;
- }else{
- /* no capture. advance to next segment */
- long bytes=oy->fifo_tail->length;
- ret-=bytes;
- oy->fifo_tail=ogg_buffer_pretruncate(oy->fifo_tail,bytes);
- }
- }
- if(!oy->fifo_tail)oy->fifo_head=0;
- oy->fifo_fill+=ret;
-
- sync_out:
- return ret;
-}
-
-/* sync the stream and get a page. Keep trying until we find a page.
- Supress 'sync errors' after reporting the first.
-
- return values:
- OGG_HOLE) 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 */
-
- while(1){
- 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 OGG_HOLE;
- }
-
- /* loop. keep looking */
-
- }
-}
-
-/* clear things to an initial state. Good to call, eg, before seeking */
-int ogg_sync_reset(ogg_sync_state *oy){
-
- ogg_buffer_release(oy->fifo_tail);
- oy->fifo_tail=0;
- oy->fifo_head=0;
- oy->fifo_fill=0;
-
- oy->unsynced=0;
- oy->headerbytes=0;
- oy->bodybytes=0;
- return OGG_SUCCESS;
-}
-
-void ogg_stream_init(ogg_stream_state *os, int serialno){
- memset(os, 0, sizeof(*os));
- os->serialno=serialno;
- os->pageno=-1;
-}
-
-ogg_stream_state *ogg_stream_create(int serialno){
- ogg_stream_state *os=_ogg_calloc(1,sizeof(*os));
- os->serialno=serialno;
- os->pageno=-1;
- return os;
-}
-
-int ogg_stream_clear(ogg_stream_state *os){
- if(os){
- ogg_buffer_release(os->header_tail);
- ogg_buffer_release(os->body_tail);
- memset(os,0,sizeof(*os));
- }
- return OGG_SUCCESS;
-}
-
-int ogg_stream_destroy(ogg_stream_state *os){
- if(os){
- ogg_buffer_release(os->header_tail);
- ogg_buffer_release(os->body_tail);
- memset(os,0,sizeof(*os));
- _ogg_free(os);
- }
- return OGG_SUCCESS;
-}
-
-
-#define FINFLAG 0x80000000UL
-#define FINMASK 0x7fffffffUL
-
-static void _next_lace(oggbyte_buffer *ob,ogg_stream_state *os){
- /* search ahead one lace */
- os->body_fill_next=0;
- while(os->laceptr<os->lacing_fill){
- int val=oggbyte_read1(ob,27+os->laceptr++);
- os->body_fill_next+=val;
- if(val<255){
- os->body_fill_next|=FINFLAG;
- os->clearflag=1;
- break;
- }
- }
-}
-
-static void _span_queued_page(ogg_stream_state *os){
- while( !(os->body_fill&FINFLAG) ){
-
- if(!os->header_tail)break;
-
- /* first flush out preceeding page header (if any). Body is
- flushed as it's consumed, so that's not done here. */
-
- if(os->lacing_fill>=0)
- os->header_tail=ogg_buffer_pretruncate(os->header_tail,
- os->lacing_fill+27);
- os->lacing_fill=0;
- os->laceptr=0;
- os->clearflag=0;
-
- if(!os->header_tail){
- os->header_head=0;
- break;
- }else{
-
- /* process/prepare next page, if any */
-
- long pageno;
- oggbyte_buffer ob;
- ogg_page og; /* only for parsing header values */
- og.header=os->header_tail; /* only for parsing header values */
- pageno=ogg_page_pageno(&og);
-
- oggbyte_init(&ob,os->header_tail);
- os->lacing_fill=oggbyte_read1(&ob,26);
-
- /* are we in sequence? */
- if(pageno!=os->pageno){
- if(os->pageno==-1) /* indicates seek or reset */
- os->holeflag=1; /* set for internal use */
- else
- os->holeflag=2; /* set for external reporting */
-
- os->body_tail=ogg_buffer_pretruncate(os->body_tail,
- os->body_fill);
- if(os->body_tail==0)os->body_head=0;
- os->body_fill=0;
-
- }
-
- if(ogg_page_continued(&og)){
- if(os->body_fill==0){
- /* continued packet, but no preceeding data to continue */
- /* dump the first partial packet on the page */
- _next_lace(&ob,os);
- os->body_tail=
- ogg_buffer_pretruncate(os->body_tail,os->body_fill_next&FINMASK);
- if(os->body_tail==0)os->body_head=0;
- /* set span flag */
- if(!os->spanflag && !os->holeflag)os->spanflag=2;
- }
- }else{
- if(os->body_fill>0){
- /* preceeding data to continue, but not a continued page */
- /* dump body_fill */
- os->body_tail=ogg_buffer_pretruncate(os->body_tail,
- os->body_fill);
- if(os->body_tail==0)os->body_head=0;
- os->body_fill=0;
-
- /* set espan flag */
- if(!os->spanflag && !os->holeflag)os->spanflag=2;
- }
- }
-
- if(os->laceptr<os->lacing_fill){
- os->granulepos=ogg_page_granulepos(&og);
-
- /* get current packet size & flag */
- _next_lace(&ob,os);
- os->body_fill+=os->body_fill_next; /* addition handles the flag fine;
- unsigned on purpose */
- /* ...and next packet size & flag */
- _next_lace(&ob,os);
-
- }
-
- os->pageno=pageno+1;
- os->e_o_s=ogg_page_eos(&og);
- os->b_o_s=ogg_page_bos(&og);
-
- }
- }
-}
-
-/* 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){
-
- int serialno=ogg_page_serialno(og);
- int version=ogg_page_version(og);
-
- /* check the serial number */
- if(serialno!=os->serialno){
- //ogg_page_release(og);
- return OGG_ESERIAL;
- }
- if(version>0){
- //ogg_page_release(og);
- return OGG_EVERSION;
- }
-
- /* add to fifos */
- if(!os->body_tail){
- os->body_tail=og->body;
- os->body_head=ogg_buffer_walk(og->body);
- }else{
- os->body_head=ogg_buffer_cat(os->body_head,og->body);
- }
- if(!os->header_tail){
- os->header_tail=og->header;
- os->header_head=ogg_buffer_walk(og->header);
- os->lacing_fill=-27;
- }else{
- os->header_head=ogg_buffer_cat(os->header_head,og->header);
- }
-
- memset(og,0,sizeof(*og));
- return OGG_SUCCESS;
-}
-
-int ogg_stream_reset(ogg_stream_state *os){
-
- ogg_buffer_release(os->header_tail);
- ogg_buffer_release(os->body_tail);
- os->header_tail=os->header_head=0;
- os->body_tail=os->body_head=0;
-
- os->e_o_s=0;
- os->b_o_s=0;
- os->pageno=-1;
- os->packetno=0;
- os->granulepos=0;
-
- os->body_fill=0;
- os->lacing_fill=0;
-
- os->holeflag=0;
- os->spanflag=0;
- os->clearflag=0;
- os->laceptr=0;
- os->body_fill_next=0;
-
- return OGG_SUCCESS;
-}
-
-int ogg_stream_reset_serialno(ogg_stream_state *os,int serialno){
- ogg_stream_reset(os);
- os->serialno=serialno;
- return OGG_SUCCESS;
-}
-
-static int _packetout(ogg_stream_state *os,ogg_packet *op,int adv){
-
- ogg_packet_release(op);
- _span_queued_page(os);
-
- if(os->holeflag){
- int temp=os->holeflag;
- if(os->clearflag)
- os->holeflag=0;
- else
- os->holeflag=1;
- if(temp==2){
- os->packetno++;
- return OGG_HOLE;
- }
- }
- if(os->spanflag){
- int temp=os->spanflag;
- if(os->clearflag)
- os->spanflag=0;
- else
- os->spanflag=1;
- if(temp==2){
- os->packetno++;
- return OGG_SPAN;
- }
- }
-
- if(!(os->body_fill&FINFLAG)) return 0;
- if(!op && !adv)return 1; /* just using peek as an inexpensive way
- to ask if there's a whole packet
- waiting */
- if(op){
- op->b_o_s=os->b_o_s;
- if(os->e_o_s && os->body_fill_next==0)
- op->e_o_s=os->e_o_s;
- else
- op->e_o_s=0;
- if( (os->body_fill&FINFLAG) && !(os->body_fill_next&FINFLAG) )
- op->granulepos=os->granulepos;
- else
- op->granulepos=-1;
- op->packetno=os->packetno;
- }
-
- if(adv){
- oggbyte_buffer ob;
- oggbyte_init(&ob,os->header_tail);
-
- /* split the body contents off */
- if(op){
- op->packet=ogg_buffer_split(&os->body_tail,&os->body_head,
- os->body_fill&FINMASK);
- op->bytes=os->body_fill&FINMASK;
- }else{
- os->body_tail=ogg_buffer_pretruncate(os->body_tail,
- os->body_fill&FINMASK);
- if(os->body_tail==0)os->body_head=0;
- }
-
- /* update lacing pointers */
- os->body_fill=os->body_fill_next;
- _next_lace(&ob,os);
- }else{
- if(op){
- op->packet=ogg_buffer_sub(os->body_tail,os->body_fill&FINMASK);
- op->bytes=os->body_fill&FINMASK;
- }
- }
-
- if(adv){
- os->packetno++;
- os->b_o_s=0;
- }
-
- 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);
-}
-
-int ogg_packet_release(ogg_packet *op) {
- if(op){
- ogg_buffer_release(op->packet);
- memset(op, 0, sizeof(*op));
- }
- return OGG_SUCCESS;
-}
-
-int ogg_page_release(ogg_page *og) {
- if(og){
- ogg_buffer_release(og->header);
- ogg_buffer_release(og->body);
- memset(og, 0, sizeof(*og));
- }
- return OGG_SUCCESS;
-}
-
-void ogg_page_dup(ogg_page *dup,ogg_page *orig){
- dup->header_len=orig->header_len;
- dup->body_len=orig->body_len;
- dup->header=ogg_buffer_dup(orig->header);
- dup->body=ogg_buffer_dup(orig->body);
-}
-
generated by cgit v1.1 at 2024-04-29 13:35:49 +0000