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
93
94
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1">
<title>libmpcdec: src/idtag.c Source File</title>
<link href="custom.css" rel="stylesheet" type="text/css">
</head><body>
<!-- Generated by Doxygen 1.4.4 -->
<div class="qindex"><a class="qindex" href="index.html">Main Page</a> | <a class="qindex" href="annotated.html">Class List</a> | <a class="qindex" href="dirs.html">Directories</a> | <a class="qindex" href="files.html">File List</a> | <a class="qindex" href="functions.html">Class Members</a> | <a class="qindex" href="globals.html">File Members</a> | <a class="qindex" href="pages.html">Related Pages</a></div>
<div class="nav">
<a class="el" href="dir_000002.html">src</a></div>
<h1>idtag.c</h1><a href="idtag_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment"> Copyright (c) 2005, The Musepack Development Team</span>
<a name="l00003"></a>00003 <span class="comment"> All rights reserved.</span>
<a name="l00004"></a>00004 <span class="comment"></span>
<a name="l00005"></a>00005 <span class="comment"> Redistribution and use in source and binary forms, with or without</span>
<a name="l00006"></a>00006 <span class="comment"> modification, are permitted provided that the following conditions are</span>
<a name="l00007"></a>00007 <span class="comment"> met:</span>
<a name="l00008"></a>00008 <span class="comment"></span>
<a name="l00009"></a>00009 <span class="comment"> * Redistributions of source code must retain the above copyright</span>
<a name="l00010"></a>00010 <span class="comment"> notice, this list of conditions and the following disclaimer.</span>
<a name="l00011"></a>00011 <span class="comment"></span>
<a name="l00012"></a>00012 <span class="comment"> * Redistributions in binary form must reproduce the above</span>
<a name="l00013"></a>00013 <span class="comment"> copyright notice, this list of conditions and the following</span>
<a name="l00014"></a>00014 <span class="comment"> disclaimer in the documentation and/or other materials provided</span>
<a name="l00015"></a>00015 <span class="comment"> with the distribution.</span>
<a name="l00016"></a>00016 <span class="comment"></span>
<a name="l00017"></a>00017 <span class="comment"> * Neither the name of the The Musepack Development Team nor the</span>
<a name="l00018"></a>00018 <span class="comment"> names of its contributors may be used to endorse or promote</span>
<a name="l00019"></a>00019 <span class="comment"> products derived from this software without specific prior</span>
<a name="l00020"></a>00020 <span class="comment"> written permission.</span>
<a name="l00021"></a>00021 <span class="comment"></span>
<a name="l00022"></a>00022 <span class="comment"> THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS</span>
<a name="l00023"></a>00023 <span class="comment"> "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT</span>
<a name="l00024"></a>00024 <span class="comment"> LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR</span>
<a name="l00025"></a>00025 <span class="comment"> A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT</span>
<a name="l00026"></a>00026 <span class="comment"> OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,</span>
<a name="l00027"></a>00027 <span class="comment"> SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT</span>
<a name="l00028"></a>00028 <span class="comment"> LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,</span>
<a name="l00029"></a>00029 <span class="comment"> DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY</span>
<a name="l00030"></a>00030 <span class="comment"> THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT</span>
<a name="l00031"></a>00031 <span class="comment"> (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE</span>
<a name="l00032"></a>00032 <span class="comment"> OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</span>
<a name="l00033"></a>00033 <span class="comment">*/</span>
<a name="l00034"></a>00034
<a name="l00038"></a>00038
<a name="l00039"></a>00039 <span class="preprocessor">#include <<a class="code" href="mpcdec_8h.html">mpcdec/mpcdec.h</a>></span>
<a name="l00040"></a>00040 <span class="preprocessor">#include <<a class="code" href="internal_8h.html">mpcdec/internal.h</a>></span>
<a name="l00041"></a>00041
<a name="l00042"></a>00042 mpc_int32_t
<a name="l00043"></a><a class="code" href="idtag_8c.html#a0">00043</a> <a class="code" href="internal_8h.html#a2">JumpID3v2</a> (<a class="code" href="structmpc__reader__t.html">mpc_reader</a>* r) {
<a name="l00044"></a>00044 <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> tmp [10];
<a name="l00045"></a>00045 mpc_uint32_t Unsynchronisation; <span class="comment">// ID3v2.4-flag</span>
<a name="l00046"></a>00046 mpc_uint32_t ExtHeaderPresent; <span class="comment">// ID3v2.4-flag</span>
<a name="l00047"></a>00047 mpc_uint32_t ExperimentalFlag; <span class="comment">// ID3v2.4-flag</span>
<a name="l00048"></a>00048 mpc_uint32_t FooterPresent; <span class="comment">// ID3v2.4-flag</span>
<a name="l00049"></a>00049 mpc_int32_t ret;
<a name="l00050"></a>00050
<a name="l00051"></a>00051 <span class="comment">// seek to first byte of mpc data</span>
<a name="l00052"></a>00052 <span class="keywordflow">if</span> (!r-><a class="code" href="structmpc__reader__t.html#o1">seek</a> (r-><a class="code" href="structmpc__reader__t.html#o5">data</a>, 0)) {
<a name="l00053"></a>00053 <span class="keywordflow">return</span> 0;
<a name="l00054"></a>00054 }
<a name="l00055"></a>00055
<a name="l00056"></a>00056 r-><a class="code" href="structmpc__reader__t.html#o0">read</a>(r-><a class="code" href="structmpc__reader__t.html#o5">data</a>, tmp, <span class="keyword">sizeof</span>(tmp));
<a name="l00057"></a>00057
<a name="l00058"></a>00058 <span class="comment">// check id3-tag</span>
<a name="l00059"></a>00059 <span class="keywordflow">if</span> ( 0 != memcmp ( tmp, <span class="stringliteral">"ID3"</span>, 3) )
<a name="l00060"></a>00060 <span class="keywordflow">return</span> 0;
<a name="l00061"></a>00061
<a name="l00062"></a>00062 <span class="comment">// read flags</span>
<a name="l00063"></a>00063 Unsynchronisation = tmp[5] & 0x80;
<a name="l00064"></a>00064 ExtHeaderPresent = tmp[5] & 0x40;
<a name="l00065"></a>00065 ExperimentalFlag = tmp[5] & 0x20;
<a name="l00066"></a>00066 FooterPresent = tmp[5] & 0x10;
<a name="l00067"></a>00067
<a name="l00068"></a>00068 <span class="keywordflow">if</span> ( tmp[5] & 0x0F )
<a name="l00069"></a>00069 <span class="keywordflow">return</span> -1; <span class="comment">// not (yet???) allowed</span>
<a name="l00070"></a>00070 <span class="keywordflow">if</span> ( (tmp[6] | tmp[7] | tmp[8] | tmp[9]) & 0x80 )
<a name="l00071"></a>00071 <span class="keywordflow">return</span> -1; <span class="comment">// not allowed</span>
<a name="l00072"></a>00072
<a name="l00073"></a>00073 <span class="comment">// read HeaderSize (syncsave: 4 * $0xxxxxxx = 28 significant bits)</span>
<a name="l00074"></a>00074 ret = tmp[6] << 21;
<a name="l00075"></a>00075 ret += tmp[7] << 14;
<a name="l00076"></a>00076 ret += tmp[8] << 7;
<a name="l00077"></a>00077 ret += tmp[9] ;
<a name="l00078"></a>00078 ret += 10;
<a name="l00079"></a>00079 <span class="keywordflow">if</span> ( FooterPresent )
<a name="l00080"></a>00080 ret += 10;
<a name="l00081"></a>00081
<a name="l00082"></a>00082 <span class="keywordflow">return</span> ret;
<a name="l00083"></a>00083 }
</pre></div><hr size="1"><address style="align: right;"><small>Generated on Sun Oct 23 16:35:24 2005 for libmpcdec by
<a href="http://www.doxygen.org/index.html">
<img src="doxygen.png" alt="doxygen" align="middle" border="0"></a> 1.4.4 </small></address>
</body>
</html>
|
