--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libtremor/info.c	Sun Apr 24 22:57:57 2011 +0200
@@ -0,0 +1,356 @@
+/********************************************************************
+ *                                                                  *
+ * 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: maintain the info structure, info <-> header packets
+
+ ********************************************************************/
+
+/* general handling of the header and the vorbis_info structure (and
+   substructures) */
+
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include "ogg.h"
+#include "ivorbiscodec.h"
+#include "codec_internal.h"
+#include "codebook.h"
+#include "registry.h"
+#include "window.h"
+#include "misc.h"
+
+/* helpers */
+static void _v_readstring(oggpack_buffer *o,char *buf,int bytes){
+  while(bytes--){
+    *buf++=oggpack_read(o,8);
+  }
+}
+
+void vorbis_comment_init(vorbis_comment *vc){
+  memset(vc,0,sizeof(*vc));
+}
+
+/* This is more or less the same as strncasecmp - but that doesn't exist
+ * everywhere, and this is a fairly trivial function, so we include it */
+static int tagcompare(const char *s1, const char *s2, int n){
+  int c=0;
+  while(c < n){
+    if(toupper(s1[c]) != toupper(s2[c]))
+      return !0;
+    c++;
+  }
+  return 0;
+}
+
+char *vorbis_comment_query(vorbis_comment *vc, char *tag, int count){
+  long i;
+  int found = 0;
+  int taglen = strlen(tag)+1; /* +1 for the = we append */
+  char *fulltag = (char *)alloca(taglen+ 1);
+
+  strcpy(fulltag, tag);
+  strcat(fulltag, "=");
+  
+  for(i=0;i<vc->comments;i++){
+    if(!tagcompare(vc->user_comments[i], fulltag, taglen)){
+      if(count == found)
+	/* We return a pointer to the data, not a copy */
+      	return vc->user_comments[i] + taglen;
+      else
+	found++;
+    }
+  }
+  return NULL; /* didn't find anything */
+}
+
+int vorbis_comment_query_count(vorbis_comment *vc, char *tag){
+  int i,count=0;
+  int taglen = strlen(tag)+1; /* +1 for the = we append */
+  char *fulltag = (char *)alloca(taglen+1);
+  strcpy(fulltag,tag);
+  strcat(fulltag, "=");
+
+  for(i=0;i<vc->comments;i++){
+    if(!tagcompare(vc->user_comments[i], fulltag, taglen))
+      count++;
+  }
+
+  return count;
+}
+
+void vorbis_comment_clear(vorbis_comment *vc){
+  if(vc){
+    long i;
+    for(i=0;i<vc->comments;i++)
+      if(vc->user_comments[i])_ogg_free(vc->user_comments[i]);
+    if(vc->user_comments)_ogg_free(vc->user_comments);
+	if(vc->comment_lengths)_ogg_free(vc->comment_lengths);
+    if(vc->vendor)_ogg_free(vc->vendor);
+    memset(vc,0,sizeof(*vc));
+  }
+}
+
+/* blocksize 0 is guaranteed to be short, 1 is guarantted to be long.
+   They may be equal, but short will never ge greater than long */
+int vorbis_info_blocksize(vorbis_info *vi,int zo){
+  codec_setup_info *ci = (codec_setup_info *)vi->codec_setup;
+  return ci ? ci->blocksizes[zo] : -1;
+}
+
+/* used by synthesis, which has a full, alloced vi */
+void vorbis_info_init(vorbis_info *vi){
+  memset(vi,0,sizeof(*vi));
+  vi->codec_setup=(codec_setup_info *)_ogg_calloc(1,sizeof(codec_setup_info));
+}
+
+void vorbis_info_clear(vorbis_info *vi){
+  codec_setup_info     *ci=(codec_setup_info *)vi->codec_setup;
+  int i;
+
+  if(ci){
+
+    for(i=0;i<ci->modes;i++)
+      if(ci->mode_param[i])_ogg_free(ci->mode_param[i]);
+
+    for(i=0;i<ci->maps;i++) /* unpack does the range checking */
+      if(ci->map_param[i])
+	_mapping_P[ci->map_type[i]]->free_info(ci->map_param[i]);
+
+    for(i=0;i<ci->floors;i++) /* unpack does the range checking */
+      if(ci->floor_param[i])
+	_floor_P[ci->floor_type[i]]->free_info(ci->floor_param[i]);
+    
+    for(i=0;i<ci->residues;i++) /* unpack does the range checking */
+      if(ci->residue_param[i])
+	_residue_P[ci->residue_type[i]]->free_info(ci->residue_param[i]);
+
+    for(i=0;i<ci->books;i++){
+      if(ci->book_param[i]){
+	/* knows if the book was not alloced */
+	vorbis_staticbook_destroy(ci->book_param[i]);
+      }
+      if(ci->fullbooks)
+	vorbis_book_clear(ci->fullbooks+i);
+    }
+    if(ci->fullbooks)
+	_ogg_free(ci->fullbooks);
+    
+    _ogg_free(ci);
+  }
+
+  memset(vi,0,sizeof(*vi));
+}
+
+/* Header packing/unpacking ********************************************/
+
+static int _vorbis_unpack_info(vorbis_info *vi,oggpack_buffer *opb){
+  codec_setup_info     *ci=(codec_setup_info *)vi->codec_setup;
+  if(!ci)return(OV_EFAULT);
+
+  vi->version=oggpack_read(opb,32);
+  if(vi->version!=0)return(OV_EVERSION);
+
+  vi->channels=oggpack_read(opb,8);
+  vi->rate=oggpack_read(opb,32);
+
+  vi->bitrate_upper=oggpack_read(opb,32);
+  vi->bitrate_nominal=oggpack_read(opb,32);
+  vi->bitrate_lower=oggpack_read(opb,32);
+
+  ci->blocksizes[0]=1<<oggpack_read(opb,4);
+  ci->blocksizes[1]=1<<oggpack_read(opb,4);
+  
+  if(vi->rate<1)goto err_out;
+  if(vi->channels<1)goto err_out;
+  if(ci->blocksizes[0]<64)goto err_out; 
+  if(ci->blocksizes[1]<ci->blocksizes[0])goto err_out;
+  if(ci->blocksizes[1]>8192)goto err_out;
+  
+  if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */
+
+  return(0);
+ err_out:
+  vorbis_info_clear(vi);
+  return(OV_EBADHEADER);
+}
+
+static int _vorbis_unpack_comment(vorbis_comment *vc,oggpack_buffer *opb){
+  int i;
+  int vendorlen=oggpack_read(opb,32);
+  if(vendorlen<0)goto err_out;
+  vc->vendor=(char *)_ogg_calloc(vendorlen+1,1);
+  _v_readstring(opb,vc->vendor,vendorlen);
+  vc->comments=oggpack_read(opb,32);
+  if(vc->comments<0)goto err_out;
+  vc->user_comments=(char **)_ogg_calloc(vc->comments+1,sizeof(*vc->user_comments));
+  vc->comment_lengths=(int *)_ogg_calloc(vc->comments+1, sizeof(*vc->comment_lengths));
+	    
+  for(i=0;i<vc->comments;i++){
+    int len=oggpack_read(opb,32);
+    if(len<0)goto err_out;
+	vc->comment_lengths[i]=len;
+    vc->user_comments[i]=(char *)_ogg_calloc(len+1,1);
+    _v_readstring(opb,vc->user_comments[i],len);
+  }	  
+  if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */
+
+  return(0);
+ err_out:
+  vorbis_comment_clear(vc);
+  return(OV_EBADHEADER);
+}
+
+/* all of the real encoding details are here.  The modes, books,
+   everything */
+static int _vorbis_unpack_books(vorbis_info *vi,oggpack_buffer *opb){
+  codec_setup_info     *ci=(codec_setup_info *)vi->codec_setup;
+  int i;
+  if(!ci)return(OV_EFAULT);
+
+  /* codebooks */
+  ci->books=oggpack_read(opb,8)+1;
+  /*ci->book_param=_ogg_calloc(ci->books,sizeof(*ci->book_param));*/
+  for(i=0;i<ci->books;i++){
+    ci->book_param[i]=(static_codebook *)_ogg_calloc(1,sizeof(*ci->book_param[i]));
+    if(vorbis_staticbook_unpack(opb,ci->book_param[i]))goto err_out;
+  }
+
+  /* time backend settings */
+  ci->times=oggpack_read(opb,6)+1;
+  /*ci->time_type=_ogg_malloc(ci->times*sizeof(*ci->time_type));*/
+  /*ci->time_param=_ogg_calloc(ci->times,sizeof(void *));*/
+  for(i=0;i<ci->times;i++){
+    ci->time_type[i]=oggpack_read(opb,16);
+    if(ci->time_type[i]<0 || ci->time_type[i]>=VI_TIMEB)goto err_out;
+    /* ci->time_param[i]=_time_P[ci->time_type[i]]->unpack(vi,opb);
+       Vorbis I has no time backend */
+    /*if(!ci->time_param[i])goto err_out;*/
+  }
+
+  /* floor backend settings */
+  ci->floors=oggpack_read(opb,6)+1;
+  /*ci->floor_type=_ogg_malloc(ci->floors*sizeof(*ci->floor_type));*/
+  /*ci->floor_param=_ogg_calloc(ci->floors,sizeof(void *));*/
+  for(i=0;i<ci->floors;i++){
+    ci->floor_type[i]=oggpack_read(opb,16);
+    if(ci->floor_type[i]<0 || ci->floor_type[i]>=VI_FLOORB)goto err_out;
+    ci->floor_param[i]=_floor_P[ci->floor_type[i]]->unpack(vi,opb);
+    if(!ci->floor_param[i])goto err_out;
+  }
+
+  /* residue backend settings */
+  ci->residues=oggpack_read(opb,6)+1;
+  /*ci->residue_type=_ogg_malloc(ci->residues*sizeof(*ci->residue_type));*/
+  /*ci->residue_param=_ogg_calloc(ci->residues,sizeof(void *));*/
+  for(i=0;i<ci->residues;i++){
+    ci->residue_type[i]=oggpack_read(opb,16);
+    if(ci->residue_type[i]<0 || ci->residue_type[i]>=VI_RESB)goto err_out;
+    ci->residue_param[i]=_residue_P[ci->residue_type[i]]->unpack(vi,opb);
+    if(!ci->residue_param[i])goto err_out;
+  }
+
+  /* map backend settings */
+  ci->maps=oggpack_read(opb,6)+1;
+  /*ci->map_type=_ogg_malloc(ci->maps*sizeof(*ci->map_type));*/
+  /*ci->map_param=_ogg_calloc(ci->maps,sizeof(void *));*/
+  for(i=0;i<ci->maps;i++){
+    ci->map_type[i]=oggpack_read(opb,16);
+    if(ci->map_type[i]<0 || ci->map_type[i]>=VI_MAPB)goto err_out;
+    ci->map_param[i]=_mapping_P[ci->map_type[i]]->unpack(vi,opb);
+    if(!ci->map_param[i])goto err_out;
+  }
+  
+  /* mode settings */
+  ci->modes=oggpack_read(opb,6)+1;
+  /*vi->mode_param=_ogg_calloc(vi->modes,sizeof(void *));*/
+  for(i=0;i<ci->modes;i++){
+    ci->mode_param[i]=(vorbis_info_mode *)_ogg_calloc(1,sizeof(*ci->mode_param[i]));
+    ci->mode_param[i]->blockflag=oggpack_read(opb,1);
+    ci->mode_param[i]->windowtype=oggpack_read(opb,16);
+    ci->mode_param[i]->transformtype=oggpack_read(opb,16);
+    ci->mode_param[i]->mapping=oggpack_read(opb,8);
+
+    if(ci->mode_param[i]->windowtype>=VI_WINDOWB)goto err_out;
+    if(ci->mode_param[i]->transformtype>=VI_WINDOWB)goto err_out;
+    if(ci->mode_param[i]->mapping>=ci->maps)goto err_out;
+  }
+  
+  if(oggpack_read(opb,1)!=1)goto err_out; /* top level EOP check */
+
+  return(0);
+ err_out:
+  vorbis_info_clear(vi);
+  return(OV_EBADHEADER);
+}
+
+/* The Vorbis header is in three packets; the initial small packet in
+   the first page that identifies basic parameters, a second packet
+   with bitstream comments and a third packet that holds the
+   codebook. */
+
+int vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc,ogg_packet *op){
+  oggpack_buffer opb;
+  
+  if(op){
+    oggpack_readinit(&opb,op->packet);
+
+    /* Which of the three types of header is this? */
+    /* Also verify header-ness, vorbis */
+    {
+      char buffer[6];
+      int packtype=oggpack_read(&opb,8);
+      memset(buffer,0,6);
+      _v_readstring(&opb,buffer,6);
+      if(memcmp(buffer,"vorbis",6)){
+	/* not a vorbis header */
+	return(OV_ENOTVORBIS);
+      }
+      switch(packtype){
+      case 0x01: /* least significant *bit* is read first */
+	if(!op->b_o_s){
+	  /* Not the initial packet */
+	  return(OV_EBADHEADER);
+	}
+	if(vi->rate!=0){
+	  /* previously initialized info header */
+	  return(OV_EBADHEADER);
+	}
+
+	return(_vorbis_unpack_info(vi,&opb));
+
+      case 0x03: /* least significant *bit* is read first */
+	if(vi->rate==0){
+	  /* um... we didn't get the initial header */
+	  return(OV_EBADHEADER);
+	}
+
+	return(_vorbis_unpack_comment(vc,&opb));
+
+      case 0x05: /* least significant *bit* is read first */
+	if(vi->rate==0 || vc->vendor==NULL){
+	  /* um... we didn;t get the initial header or comments yet */
+	  return(OV_EBADHEADER);
+	}
+
+	return(_vorbis_unpack_books(vi,&opb));
+
+      default:
+	/* Not a valid vorbis header type */
+	return(OV_EBADHEADER);
+	break;
+      }
+    }
+  }
+  return(OV_EBADHEADER);
+}
+