1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
|
// The authors have released ID3Lib as Public Domain (PD) and claim no copyright,
// patent or other intellectual property protection in this work. This means that
// it may be modified, redistributed and used in commercial and non-commercial
// software and hardware without restrictions. ID3Lib is distributed on an "AS IS"
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.
//
// The ID3Lib authors encourage improvements and optimisations to be sent to the
// ID3Lib coordinator, currently Dirk Mahoney (dirk@id3.org). Approved
// submissions may be altered, and will be included and released under these terms.
//
// Mon Nov 23 18:34:01 1998
#include <string.h>
#include <memory.h>
#include "id3_header_tag.h"
#include "id3_error.h"
// Analyses a buffer to determine if we have a valid ID3v2 tag header.
// If so, return the number of bytes (starting _after_ the header) to
// read so we get all of the tag
lsint ID3_IsTagHeader ( uchar header[ ID3_TAGHEADERSIZE ] )
{
lsint tagSize = -1;
if ( memcmp ( "ID3", header, 3 ) == 0 )
if ( header[ 3 ] <= ID3_TAGVERSION )
{
int28 temp = &header[ 6 ];
tagSize = temp.get();
}
return tagSize;
}
luint ID3_TagHeader::Size ( void )
{
luint bytesUsed = ID3_TAGHEADERSIZE;
if ( info->hasExtHeader )
bytesUsed += info->extHeaderBytes + sizeof ( luint );
return bytesUsed;
}
luint ID3_TagHeader::Render ( uchar *buffer )
{
luint bytesUsed = 0;
memcpy ( &buffer[ bytesUsed ], (uchar *) ID3_TAGID, strlen ( ID3_TAGID ) );
bytesUsed += strlen ( ID3_TAGID );
buffer[ bytesUsed++ ] = version;
buffer[ bytesUsed++ ] = revision;
// do the automatic flags
if ( info->setExpBit )
flags |= ID3HF_EXPERIMENTAL;
if ( info->hasExtHeader )
flags |= ID3HF_EXTENDEDHEADER;
// set the flags byte in the header
buffer[ bytesUsed++ ] = (uchar) ( flags & 0xFF );
int28 temp = dataSize;
for ( luint i = 0; i < sizeof ( luint ); i++ )
buffer[ bytesUsed++ ] = temp[ i ];
// now we render the extended header
if ( info->hasExtHeader )
{
luint i;
for ( i = 0; i < sizeof ( luint ); i++ )
buffer[ bytesUsed + i ] = (uchar) ( ( info->extHeaderBytes >> ( ( sizeof ( luint ) - i - 1 ) * 8 ) ) & 0xFF );
bytesUsed += i;
}
bytesUsed = Size();
return bytesUsed;
}
|
