/*
* NAME: v1->render()
* DESCRIPTION: render an ID3v1 (or ID3v1.1) tag
*/
static
id3_length_t v1_render(struct id3_tag const *tag, id3_byte_t *buffer)
{
struct id3_frame *frame;
unsigned int number, i;
if (buffer == 0)
return 128;
id3_render_immediate(&buffer, "TAG", 3);
v1_renderstr(tag, ID3_FRAME_TITLE, &buffer, 30);
v1_renderstr(tag, ID3_FRAME_ARTIST, &buffer, 30);
v1_renderstr(tag, ID3_FRAME_ALBUM, &buffer, 30);
v1_renderstr(tag, ID3_FRAME_YEAR, &buffer, 4);
v1_renderstr(tag, ID3_FRAME_COMMENT, &buffer, 30);
frame = id3_tag_findframe(tag, ID3_FRAME_TRACK, 0);
if (frame) {
number = id3_ucs4_getnumber(id3_field_getstrings(&frame->fields[1], 0));
if (number & 0xff) {
buffer[-2] = 0;
buffer[-1] = number;
}
}
frame = id3_tag_findframe(tag, ID3_FRAME_GENRE, 0);
number = frame ?
id3_ucs4_getnumber(id3_field_getstrings(&frame->fields[1], 0)) : 0xff;
id3_render_int(&buffer, number, 1);
/* make sure the tag is not empty */
buffer -= 128;
for (i = 3; i < 127; ++i) {
if (buffer[i] != ' ')
break;
}
return (i == 127 && buffer[127] == 0xff) ? 0 : 128;
}
/*
* NAME: tag->render()
* DESCRIPTION: render a complete ID3 tag
*/
id3_length_t id3_tag_render(struct id3_tag const *tag, id3_byte_t *buffer)
{
id3_length_t size = 0;
id3_byte_t **ptr,
*header_ptr = 0, *tagsize_ptr = 0, *crc_ptr = 0, *frames_ptr = 0;
int flags, extendedflags;
unsigned int i;
assert(tag);
if (tag->options & ID3_TAG_OPTION_ID3V1)
return v1_render(tag, buffer);
/* a tag must contain at least one (renderable) frame */
for (i = 0; i < tag->nframes; ++i) {
if (id3_frame_render(tag->frames[i], 0, 0) > 0)
break;
}
if (i == tag->nframes)
return 0;
ptr = buffer ? &buffer : 0;
/* get flags */
flags = tag->flags & ID3_TAG_FLAG_KNOWNFLAGS;
extendedflags = tag->extendedflags & ID3_TAG_EXTENDEDFLAG_KNOWNFLAGS;
extendedflags &= ~ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT;
if (tag->options & ID3_TAG_OPTION_CRC)
extendedflags |= ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT;
extendedflags &= ~ID3_TAG_EXTENDEDFLAG_TAGRESTRICTIONS;
if (tag->restrictions)
extendedflags |= ID3_TAG_EXTENDEDFLAG_TAGRESTRICTIONS;
flags &= ~ID3_TAG_FLAG_UNSYNCHRONISATION;
if (tag->options & ID3_TAG_OPTION_UNSYNCHRONISATION)
flags |= ID3_TAG_FLAG_UNSYNCHRONISATION;
flags &= ~ID3_TAG_FLAG_EXTENDEDHEADER;
if (extendedflags)
flags |= ID3_TAG_FLAG_EXTENDEDHEADER;
flags &= ~ID3_TAG_FLAG_FOOTERPRESENT;
if (tag->options & ID3_TAG_OPTION_APPENDEDTAG)
flags |= ID3_TAG_FLAG_FOOTERPRESENT;
/* header */
if (ptr)
header_ptr = *ptr;
size += id3_render_immediate(ptr, "ID3", 3);
size += id3_render_int(ptr, ID3_TAG_VERSION, 2);
size += id3_render_int(ptr, flags, 1);
if (ptr)
tagsize_ptr = *ptr;
size += id3_render_syncsafe(ptr, 0, 4);
/* extended header */
if (flags & ID3_TAG_FLAG_EXTENDEDHEADER) {
id3_length_t ehsize = 0;
id3_byte_t *ehsize_ptr = 0;
if (ptr)
ehsize_ptr = *ptr;
ehsize += id3_render_syncsafe(ptr, 0, 4);
ehsize += id3_render_int(ptr, 1, 1);
ehsize += id3_render_int(ptr, extendedflags, 1);
if (extendedflags & ID3_TAG_EXTENDEDFLAG_TAGISANUPDATE)
ehsize += id3_render_int(ptr, 0, 1);
if (extendedflags & ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT) {
ehsize += id3_render_int(ptr, 5, 1);
if (ptr)
crc_ptr = *ptr;
ehsize += id3_render_syncsafe(ptr, 0, 5);
}
if (extendedflags & ID3_TAG_EXTENDEDFLAG_TAGRESTRICTIONS) {
ehsize += id3_render_int(ptr, 1, 1);
ehsize += id3_render_int(ptr, tag->restrictions, 1);
}
if (ehsize_ptr)
id3_render_syncsafe(&ehsize_ptr, ehsize, 4);
size += ehsize;
}
/* frames */
if (ptr)
frames_ptr = *ptr;
for (i = 0; i < tag->nframes; ++i)
size += id3_frame_render(tag->frames[i], ptr, tag->options);
/* padding */
if (!(flags & ID3_TAG_FLAG_FOOTERPRESENT)) {
if (size < tag->paddedsize)
size += id3_render_padding(ptr, 0, tag->paddedsize - size);
else if (tag->options & ID3_TAG_OPTION_UNSYNCHRONISATION) {
if (ptr == 0)
size += 1;
else {
if ((*ptr)[-1] == 0xff)
size += id3_render_padding(ptr, 0, 1);
}
}
}
/* patch tag size and CRC */
if (tagsize_ptr)
id3_render_syncsafe(&tagsize_ptr, size - 10, 4);
if (crc_ptr) {
id3_render_syncsafe(&crc_ptr,
id3_crc_compute(frames_ptr, *ptr - frames_ptr), 5);
}
/* footer */
if (flags & ID3_TAG_FLAG_FOOTERPRESENT) {
size += id3_render_immediate(ptr, "3DI", 3);
size += id3_render_binary(ptr, header_ptr + 3, 7);
}
return size;
}
/*
* NAME: v1->render()
* DESCRIPTION: render an ID3v1 (or ID3v1.1) tag
*/
static
id3_length_t v1_render(struct id3_tag const *tag, id3_byte_t *buffer)
{
id3_byte_t data[128], *ptr;
struct id3_frame *frame;
unsigned int i;
int genre = -1;
ptr = data;
id3_render_immediate(&ptr, "TAG", 3);
v1_renderstr(tag, ID3_FRAME_TITLE, &ptr, 30);
v1_renderstr(tag, ID3_FRAME_ARTIST, &ptr, 30);
v1_renderstr(tag, ID3_FRAME_ALBUM, &ptr, 30);
v1_renderstr(tag, ID3_FRAME_YEAR, &ptr, 4);
v1_renderstr(tag, ID3_FRAME_COMMENT, &ptr, 30);
/* ID3v1.1 track number */
frame = id3_tag_findframe(tag, ID3_FRAME_TRACK, 0);
if (frame) {
unsigned int track;
track = id3_ucs4_getnumber(id3_field_getstrings(&frame->fields[1], 0));
if (track > 0 && track <= 0xff) {
ptr[-2] = 0;
ptr[-1] = track;
}
}
/* ID3v1 genre number */
frame = id3_tag_findframe(tag, ID3_FRAME_GENRE, 0);
if (frame) {
unsigned int nstrings;
nstrings = id3_field_getnstrings(&frame->fields[1]);
for (i = 0; i < nstrings; ++i) {
genre = id3_genre_number(id3_field_getstrings(&frame->fields[1], i));
if (genre != -1)
break;
}
if (i == nstrings && nstrings > 0)
genre = ID3_GENRE_OTHER;
}
id3_render_int(&ptr, genre, 1);
/* make sure the tag is not empty */
if (genre == -1) {
for (i = 3; i < 127; ++i) {
if (data[i] != ' ')
break;
}
if (i == 127)
return 0;
}
if (buffer)
memcpy(buffer, data, 128);
return 128;
}
/*
* NAME: field->render()
* DESCRIPTION: render a field value
*/
id3_length_t id3_field_render(union id3_field const *field, id3_byte_t **ptr,
enum id3_field_textencoding *encoding,
int terminate)
{
id3_length_t size;
unsigned int i;
assert(field && encoding);
switch (field->type) {
case ID3_FIELD_TYPE_INT32:
return id3_render_int(ptr, field->number.value, 4);
case ID3_FIELD_TYPE_INT24:
return id3_render_int(ptr, field->number.value, 3);
case ID3_FIELD_TYPE_INT16:
return id3_render_int(ptr, field->number.value, 2);
case ID3_FIELD_TYPE_TEXTENCODING:
*encoding = field->number.value;
case ID3_FIELD_TYPE_INT8:
return id3_render_int(ptr, field->number.value, 1);
case ID3_FIELD_TYPE_LATIN1:
case ID3_FIELD_TYPE_LATIN1FULL:
return id3_render_latin1(ptr, field->latin1.ptr, terminate);
case ID3_FIELD_TYPE_LATIN1LIST:
size = 0;
for (i = 0; i < field->latin1list.nstrings; ++i) {
size += id3_render_latin1(ptr, field->latin1list.strings[i],
(i < field->latin1list.nstrings - 1) ||
terminate);
}
return size;
case ID3_FIELD_TYPE_STRING:
case ID3_FIELD_TYPE_STRINGFULL:
return id3_render_string(ptr, field->string.ptr, *encoding, terminate);
case ID3_FIELD_TYPE_STRINGLIST:
size = 0;
for (i = 0; i < field->stringlist.nstrings; ++i) {
size += id3_render_string(ptr, field->stringlist.strings[i], *encoding,
(i < field->stringlist.nstrings - 1) ||
terminate);
}
return size;
case ID3_FIELD_TYPE_LANGUAGE:
return id3_render_immediate(ptr, field->immediate.value, 3);
case ID3_FIELD_TYPE_FRAMEID:
return id3_render_immediate(ptr, field->immediate.value, 4);
case ID3_FIELD_TYPE_DATE:
return id3_render_immediate(ptr, field->immediate.value, 8);
case ID3_FIELD_TYPE_INT32PLUS:
case ID3_FIELD_TYPE_BINARYDATA:
return id3_render_binary(ptr, field->binary.data, field->binary.length);
}
return 0;
}
