static unsigned char *
set_frame(unsigned char *frame, unsigned long id, const char *text,
size_t length)
{
if (length) {
frame = set_4_byte_value(frame, id);
/* Set frame size = total size - header size. Frame header and field
* bytes include 2-byte header flags, 1 encoding descriptor byte, and
* for comment frames: 3-byte language descriptor and 1 content
* descriptor byte */
frame = set_4_byte_value(frame, ((id == COMMENT_FRAME_ID) ? 5 : 1)
+ length);
/* clear 2-byte header flags */
*frame++ = 0;
*frame++ = 0;
/* clear 1 encoding descriptor byte to indicate ISO-8859-1 format */
*frame++ = 0;
if (id == COMMENT_FRAME_ID) {
/* use id3lib-compatible bogus language descriptor */
*frame++ = 'X';
*frame++ = 'X';
*frame++ = 'X';
/* clear 1 byte to make content descriptor empty string */
*frame++ = 0;
}
while (length--) {
*frame++ = *text++;
}
}
return frame;
}
static unsigned char *
set_frame_apic(unsigned char *frame, const char *mimetype, const unsigned char *data, size_t size)
{
/* ID3v2.3 standard APIC frame:
* <Header for 'Attached picture', ID: "APIC">
* Text encoding $xx
* MIME type <text string> $00
* Picture type $xx
* Description <text string according to encoding> $00 (00)
* Picture data <binary data>
*/
if (mimetype && data && size) {
frame = set_4_byte_value(frame, FRAME_ID('A', 'P', 'I', 'C'));
frame = set_4_byte_value(frame, (unsigned long) (4 + strlen(mimetype) + size));
/* clear 2-byte header flags */
*frame++ = 0;
*frame++ = 0;
/* clear 1 encoding descriptor byte to indicate ISO-8859-1 format */
*frame++ = 0;
/* copy mime_type */
while (*mimetype) {
*frame++ = *mimetype++;
}
*frame++ = 0;
/* set picture type to 0 */
*frame++ = 0;
/* empty description field */
*frame++ = 0;
/* copy the image data */
while (size--) {
*frame++ = *data++;
}
}
return frame;
}
static unsigned char *
set_frame_custom2(unsigned char *frame, FrameDataNode const *node)
{
size_t const n = sizeOfNode(node);
if (n > 10) {
frame = set_4_byte_value(frame, node->fid);
frame = set_4_byte_value(frame, (unsigned long) (n - 10));
/* clear 2-byte header flags */
*frame++ = 0;
*frame++ = 0;
/* clear 1 encoding descriptor byte to indicate ISO-8859-1 format */
*frame++ = node->txt.enc == 1 ? 1 : 0;
if (node->dsc.dim > 0) {
if (node->dsc.enc != 1) {
frame = writeChars(frame, node->dsc.ptr.l, node->dsc.dim);
*frame++ = 0;
}
else {
frame = writeUcs2s(frame, node->dsc.ptr.u, node->dsc.dim);
*frame++ = 0;
*frame++ = 0;
}
}
if (node->txt.enc != 1) {
frame = writeChars(frame, node->txt.ptr.l, node->txt.dim);
}
else {
frame = writeUcs2s(frame, node->txt.ptr.u, node->txt.dim);
}
}
return frame;
}
static unsigned char *
set_frame_comment(unsigned char *frame, FrameDataNode const *node)
{
size_t const n = sizeOfCommentNode(node);
if (n > 10) {
frame = set_4_byte_value(frame, node->fid);
frame = set_4_byte_value(frame, (uint32_t) (n - 10));
/* clear 2-byte header flags */
*frame++ = 0;
*frame++ = 0;
/* encoding descriptor byte */
*frame++ = node->txt.enc == 1 ? 1 : 0;
/* 3 bytes language */
*frame++ = node->lng[0];
*frame++ = node->lng[1];
*frame++ = node->lng[2];
/* descriptor with zero byte(s) separator */
if (node->dsc.enc != 1) {
frame = writeChars(frame, node->dsc.ptr.l, node->dsc.dim);
*frame++ = 0;
}
else {
frame = writeUcs2s(frame, node->dsc.ptr.u, node->dsc.dim);
*frame++ = 0;
*frame++ = 0;
}
/* comment full text */
if (node->txt.enc != 1) {
frame = writeChars(frame, node->txt.ptr.l, node->txt.dim);
}
else {
frame = writeUcs2s(frame, node->txt.ptr.u, node->txt.dim);
}
}
return frame;
}
static unsigned char *
set_frame_custom(unsigned char *frame, const char *fieldvalue)
{
if (fieldvalue && *fieldvalue) {
const char *value = fieldvalue + 5;
size_t length = strlen(value);
*frame++ = *fieldvalue++;
*frame++ = *fieldvalue++;
*frame++ = *fieldvalue++;
*frame++ = *fieldvalue++;
frame = set_4_byte_value(frame, (unsigned long) (strlen(value) + 1));
/* clear 2-byte header flags */
*frame++ = 0;
*frame++ = 0;
/* clear 1 encoding descriptor byte to indicate ISO-8859-1 format */
*frame++ = 0;
while (length--) {
*frame++ = *value++;
}
}
return frame;
}