Recognizes if input is ogg or not.
[xiph.git] / Tremor / info.c
blob33acf16b2701dcb5473b242c8669ba1f39fd4dc6
1 /********************************************************************
2 * *
3 * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE. *
4 * *
5 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
6 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
7 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
8 * *
9 * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2003 *
10 * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ *
11 * *
12 ********************************************************************
14 function: maintain the info structure, info <-> header packets
16 ********************************************************************/
18 /* general handling of the header and the vorbis_info structure (and
19 substructures) */
21 #include <stdlib.h>
22 #include <string.h>
23 #include <ctype.h>
24 #include "ogg.h"
25 #include "ivorbiscodec.h"
26 #include "codec_internal.h"
27 #include "codebook.h"
28 #include "registry.h"
29 #include "window.h"
30 #include "misc.h"
32 /* helpers */
33 static void _v_readstring(oggpack_buffer *o,char *buf,int bytes){
34 while(bytes--){
35 *buf++=oggpack_read(o,8);
39 void vorbis_comment_init(vorbis_comment *vc){
40 memset(vc,0,sizeof(*vc));
43 /* This is more or less the same as strncasecmp - but that doesn't exist
44 * everywhere, and this is a fairly trivial function, so we include it */
45 static int tagcompare(const char *s1, const char *s2, int n){
46 int c=0;
47 while(c < n){
48 if(toupper(s1[c]) != toupper(s2[c]))
49 return !0;
50 c++;
52 return 0;
55 char *vorbis_comment_query(vorbis_comment *vc, char *tag, int count){
56 long i;
57 int found = 0;
58 int taglen = strlen(tag)+1; /* +1 for the = we append */
59 char *fulltag = (char *)alloca(taglen+ 1);
61 strcpy(fulltag, tag);
62 strcat(fulltag, "=");
64 for(i=0;i<vc->comments;i++){
65 if(!tagcompare(vc->user_comments[i], fulltag, taglen)){
66 if(count == found)
67 /* We return a pointer to the data, not a copy */
68 return vc->user_comments[i] + taglen;
69 else
70 found++;
73 return NULL; /* didn't find anything */
76 int vorbis_comment_query_count(vorbis_comment *vc, char *tag){
77 int i,count=0;
78 int taglen = strlen(tag)+1; /* +1 for the = we append */
79 char *fulltag = (char *)alloca(taglen+1);
80 strcpy(fulltag,tag);
81 strcat(fulltag, "=");
83 for(i=0;i<vc->comments;i++){
84 if(!tagcompare(vc->user_comments[i], fulltag, taglen))
85 count++;
88 return count;
91 void vorbis_comment_clear(vorbis_comment *vc){
92 if(vc){
93 long i;
94 for(i=0;i<vc->comments;i++)
95 if(vc->user_comments[i])_ogg_free(vc->user_comments[i]);
96 if(vc->user_comments)_ogg_free(vc->user_comments);
97 if(vc->comment_lengths)_ogg_free(vc->comment_lengths);
98 if(vc->vendor)_ogg_free(vc->vendor);
99 memset(vc,0,sizeof(*vc));
103 /* blocksize 0 is guaranteed to be short, 1 is guarantted to be long.
104 They may be equal, but short will never ge greater than long */
105 int vorbis_info_blocksize(vorbis_info *vi,int zo){
106 codec_setup_info *ci = (codec_setup_info *)vi->codec_setup;
107 return ci ? ci->blocksizes[zo] : -1;
110 /* used by synthesis, which has a full, alloced vi */
111 void vorbis_info_init(vorbis_info *vi){
112 memset(vi,0,sizeof(*vi));
113 vi->codec_setup=(codec_setup_info *)_ogg_calloc(1,sizeof(codec_setup_info));
116 void vorbis_info_clear(vorbis_info *vi){
117 codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
118 int i;
120 if(ci){
122 for(i=0;i<ci->modes;i++)
123 if(ci->mode_param[i])_ogg_free(ci->mode_param[i]);
125 for(i=0;i<ci->maps;i++) /* unpack does the range checking */
126 if(ci->map_param[i])
127 _mapping_P[ci->map_type[i]]->free_info(ci->map_param[i]);
129 for(i=0;i<ci->floors;i++) /* unpack does the range checking */
130 if(ci->floor_param[i])
131 _floor_P[ci->floor_type[i]]->free_info(ci->floor_param[i]);
133 for(i=0;i<ci->residues;i++) /* unpack does the range checking */
134 if(ci->residue_param[i])
135 _residue_P[ci->residue_type[i]]->free_info(ci->residue_param[i]);
137 for(i=0;i<ci->books;i++){
138 if(ci->book_param[i]){
139 /* knows if the book was not alloced */
140 vorbis_staticbook_destroy(ci->book_param[i]);
142 if(ci->fullbooks)
143 vorbis_book_clear(ci->fullbooks+i);
145 if(ci->fullbooks)
146 _ogg_free(ci->fullbooks);
148 _ogg_free(ci);
151 memset(vi,0,sizeof(*vi));
154 /* Header packing/unpacking ********************************************/
156 static int _vorbis_unpack_info(vorbis_info *vi,oggpack_buffer *opb){
157 codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
158 if(!ci)return(OV_EFAULT);
160 vi->version=oggpack_read(opb,32);
161 if(vi->version!=0)return(OV_EVERSION);
163 vi->channels=oggpack_read(opb,8);
164 vi->rate=oggpack_read(opb,32);
166 vi->bitrate_upper=oggpack_read(opb,32);
167 vi->bitrate_nominal=oggpack_read(opb,32);
168 vi->bitrate_lower=oggpack_read(opb,32);
170 ci->blocksizes[0]=1<<oggpack_read(opb,4);
171 ci->blocksizes[1]=1<<oggpack_read(opb,4);
173 if(vi->rate<1)goto err_out;
174 if(vi->channels<1)goto err_out;
175 if(ci->blocksizes[0]<64)goto err_out;
176 if(ci->blocksizes[1]<ci->blocksizes[0])goto err_out;
177 if(ci->blocksizes[1]>8192)goto err_out;
179 if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */
181 return(0);
182 err_out:
183 vorbis_info_clear(vi);
184 return(OV_EBADHEADER);
187 static int _vorbis_unpack_comment(vorbis_comment *vc,oggpack_buffer *opb){
188 int i;
189 int vendorlen=oggpack_read(opb,32);
190 if(vendorlen<0)goto err_out;
191 vc->vendor=(char *)_ogg_calloc(vendorlen+1,1);
192 _v_readstring(opb,vc->vendor,vendorlen);
193 vc->comments=oggpack_read(opb,32);
194 if(vc->comments<0)goto err_out;
195 vc->user_comments=(char **)_ogg_calloc(vc->comments+1,sizeof(*vc->user_comments));
196 vc->comment_lengths=(int *)_ogg_calloc(vc->comments+1, sizeof(*vc->comment_lengths));
198 for(i=0;i<vc->comments;i++){
199 int len=oggpack_read(opb,32);
200 if(len<0)goto err_out;
201 vc->comment_lengths[i]=len;
202 vc->user_comments[i]=(char *)_ogg_calloc(len+1,1);
203 _v_readstring(opb,vc->user_comments[i],len);
205 if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */
207 return(0);
208 err_out:
209 vorbis_comment_clear(vc);
210 return(OV_EBADHEADER);
213 /* all of the real encoding details are here. The modes, books,
214 everything */
215 static int _vorbis_unpack_books(vorbis_info *vi,oggpack_buffer *opb){
216 codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
217 int i;
218 if(!ci)return(OV_EFAULT);
220 /* codebooks */
221 ci->books=oggpack_read(opb,8)+1;
222 /*ci->book_param=_ogg_calloc(ci->books,sizeof(*ci->book_param));*/
223 for(i=0;i<ci->books;i++){
224 ci->book_param[i]=(static_codebook *)_ogg_calloc(1,sizeof(*ci->book_param[i]));
225 if(vorbis_staticbook_unpack(opb,ci->book_param[i]))goto err_out;
228 /* time backend settings */
229 ci->times=oggpack_read(opb,6)+1;
230 /*ci->time_type=_ogg_malloc(ci->times*sizeof(*ci->time_type));*/
231 /*ci->time_param=_ogg_calloc(ci->times,sizeof(void *));*/
232 for(i=0;i<ci->times;i++){
233 ci->time_type[i]=oggpack_read(opb,16);
234 if(ci->time_type[i]<0 || ci->time_type[i]>=VI_TIMEB)goto err_out;
235 /* ci->time_param[i]=_time_P[ci->time_type[i]]->unpack(vi,opb);
236 Vorbis I has no time backend */
237 /*if(!ci->time_param[i])goto err_out;*/
240 /* floor backend settings */
241 ci->floors=oggpack_read(opb,6)+1;
242 /*ci->floor_type=_ogg_malloc(ci->floors*sizeof(*ci->floor_type));*/
243 /*ci->floor_param=_ogg_calloc(ci->floors,sizeof(void *));*/
244 for(i=0;i<ci->floors;i++){
245 ci->floor_type[i]=oggpack_read(opb,16);
246 if(ci->floor_type[i]<0 || ci->floor_type[i]>=VI_FLOORB)goto err_out;
247 ci->floor_param[i]=_floor_P[ci->floor_type[i]]->unpack(vi,opb);
248 if(!ci->floor_param[i])goto err_out;
251 /* residue backend settings */
252 ci->residues=oggpack_read(opb,6)+1;
253 /*ci->residue_type=_ogg_malloc(ci->residues*sizeof(*ci->residue_type));*/
254 /*ci->residue_param=_ogg_calloc(ci->residues,sizeof(void *));*/
255 for(i=0;i<ci->residues;i++){
256 ci->residue_type[i]=oggpack_read(opb,16);
257 if(ci->residue_type[i]<0 || ci->residue_type[i]>=VI_RESB)goto err_out;
258 ci->residue_param[i]=_residue_P[ci->residue_type[i]]->unpack(vi,opb);
259 if(!ci->residue_param[i])goto err_out;
262 /* map backend settings */
263 ci->maps=oggpack_read(opb,6)+1;
264 /*ci->map_type=_ogg_malloc(ci->maps*sizeof(*ci->map_type));*/
265 /*ci->map_param=_ogg_calloc(ci->maps,sizeof(void *));*/
266 for(i=0;i<ci->maps;i++){
267 ci->map_type[i]=oggpack_read(opb,16);
268 if(ci->map_type[i]<0 || ci->map_type[i]>=VI_MAPB)goto err_out;
269 ci->map_param[i]=_mapping_P[ci->map_type[i]]->unpack(vi,opb);
270 if(!ci->map_param[i])goto err_out;
273 /* mode settings */
274 ci->modes=oggpack_read(opb,6)+1;
275 /*vi->mode_param=_ogg_calloc(vi->modes,sizeof(void *));*/
276 for(i=0;i<ci->modes;i++){
277 ci->mode_param[i]=(vorbis_info_mode *)_ogg_calloc(1,sizeof(*ci->mode_param[i]));
278 ci->mode_param[i]->blockflag=oggpack_read(opb,1);
279 ci->mode_param[i]->windowtype=oggpack_read(opb,16);
280 ci->mode_param[i]->transformtype=oggpack_read(opb,16);
281 ci->mode_param[i]->mapping=oggpack_read(opb,8);
283 if(ci->mode_param[i]->windowtype>=VI_WINDOWB)goto err_out;
284 if(ci->mode_param[i]->transformtype>=VI_WINDOWB)goto err_out;
285 if(ci->mode_param[i]->mapping>=ci->maps)goto err_out;
288 if(oggpack_read(opb,1)!=1)goto err_out; /* top level EOP check */
290 return(0);
291 err_out:
292 vorbis_info_clear(vi);
293 return(OV_EBADHEADER);
296 /* The Vorbis header is in three packets; the initial small packet in
297 the first page that identifies basic parameters, a second packet
298 with bitstream comments and a third packet that holds the
299 codebook. */
301 int vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc,ogg_packet *op){
302 oggpack_buffer opb;
304 if(op){
305 oggpack_readinit(&opb,op->packet);
307 /* Which of the three types of header is this? */
308 /* Also verify header-ness, vorbis */
310 char buffer[6];
311 int packtype=oggpack_read(&opb,8);
312 memset(buffer,0,6);
313 _v_readstring(&opb,buffer,6);
314 if(memcmp(buffer,"vorbis",6)){
315 /* not a vorbis header */
316 return(OV_ENOTVORBIS);
318 switch(packtype){
319 case 0x01: /* least significant *bit* is read first */
320 if(!op->b_o_s){
321 /* Not the initial packet */
322 return(OV_EBADHEADER);
324 if(vi->rate!=0){
325 /* previously initialized info header */
326 return(OV_EBADHEADER);
329 return(_vorbis_unpack_info(vi,&opb));
331 case 0x03: /* least significant *bit* is read first */
332 if(vi->rate==0){
333 /* um... we didn't get the initial header */
334 return(OV_EBADHEADER);
337 return(_vorbis_unpack_comment(vc,&opb));
339 case 0x05: /* least significant *bit* is read first */
340 if(vi->rate==0 || vc->vendor==NULL){
341 /* um... we didn;t get the initial header or comments yet */
342 return(OV_EBADHEADER);
345 return(_vorbis_unpack_books(vi,&opb));
347 default:
348 /* Not a valid vorbis header type */
349 return(OV_EBADHEADER);
350 break;
354 return(OV_EBADHEADER);