forked from jackaudio/jackaudio.github.com
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathporting-guide.html
More file actions
113 lines (111 loc) · 7.08 KB
/
Copy pathporting-guide.html
File metadata and controls
113 lines (111 loc) · 7.08 KB
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
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<meta name="generator" content="Doxygen 1.8.13"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>JACK-AUDIO-CONNECTION-KIT: Porting JACK</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/searchdata.js"></script>
<script type="text/javascript" src="search/search.js"></script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td id="projectalign" style="padding-left: 0.5em;">
<div id="projectname">JACK-AUDIO-CONNECTION-KIT
</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.8.13 -->
<script type="text/javascript">
var searchBox = new SearchBox("searchBox", "search",false,'Search');
</script>
<script type="text/javascript" src="menudata.js"></script>
<script type="text/javascript" src="menu.js"></script>
<script type="text/javascript">
$(function() {
initMenu('',true,false,'search.php','Search');
$(document).ready(function() { init_search(); });
});
</script>
<div id="main-nav"></div>
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
onkeydown="return searchBox.OnSearchSelectKey(event)">
</div>
<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0"
name="MSearchResults" id="MSearchResults">
</iframe>
</div>
</div><!-- top -->
<div class="header">
<div class="headertitle">
<div class="title">Porting JACK </div> </div>
</div><!--header-->
<div class="contents">
<div class="textblock"><p>The <a class="el" href="index.html">JACK Audio Connection Kit</a> is designed to be portable to any system supporting the relevant POSIX and C language standards. It currently works with GNU/Linux and Mac OS X on several different processor architectures. This document describes the steps needed to port JACK to another platform, and the methods used to provide portability.</p>
<ul>
<li><a class="el" href="porting-guide.html#portrequirements">Requirements</a></li>
<li><a class="el" href="porting-guide.html#portoverview">Overview</a></li>
<li><a class="el" href="porting-guide.html#portopsys">Operating System Dependencies</a></li>
<li>portcpu</li>
<li><a class="el" href="porting-guide.html#portissues">Issues Not Addressed</a></li>
</ul>
<h1><a class="anchor" id="portrequirements"></a>
Requirements</h1>
<ul>
<li>Each platform should build directly from CVS or from a tarball using the GNU <code></code>./configure tools. Platform-specific toolsets can by used for development, but the GNU tools should at least work for basic distribution and configuration.</li>
<li>For long-term maintainability we want to minimize the use of conditional compilation in source files.</li>
<li>We should provide generic versions of all system-dependent headers, so platforms need only provide those they modify.</li>
<li>In some cases, operating system-specific information must be able to override processor-specific data.</li>
</ul>
<h1><a class="anchor" id="portoverview"></a>
Overview</h1>
<p>JACK relies on two types of platform-specific headers:</p>
<ul>
<li><a class="el" href="porting-guide.html#portopsys">Operating System Dependencies</a></li>
<li>portcpu</li>
</ul>
<p>OS-specific headers take precedence over CPU-specific headers.</p>
<p>The JACK <code>configure.host</code> script and its system-dependent header directories were adapted from the <code>libstdc++-v3</code> component of the GNU Compiler Collective, <a href="http://gcc.gnu.org">http://gcc.gnu.org</a>.</p>
<h1><a class="anchor" id="portlang"></a>
C Language Dependencies</h1>
<p>JACK is written to conform with C99, as defined in International Standard ISO/IEC 9899:1999. Because many existing compilers do not fully support this standard, some new features should be avoided for portablility reasons. For example, variables should not be declared in the middle of a compound statement, because many compilers still cannot handle that language extension.</p>
<h1><a class="anchor" id="portopsys"></a>
Operating System Dependencies</h1>
<p>JACK is written for a POSIX environment compliant with IEEE Std 1003.1-2001, ISO/IEC 9945:2003, including the POSIX Threads Extension (1003.1c-1995) and the Realtime and Realtime Threads feature groups. When some needed POSIX feature is missing on a platform, the preferred solution is to provide a substitute, as with the <code>fakepoll.c</code> implementation for Mac OS X.</p>
<p>Whenever possible, OS dependencies should be auto-detected by <code>configure</code>. Sometimes they can be isolated in OS-specific header files, found in subdirectories of <code>config/os</code> and referenced with a <code><sysdeps/xxx.h></code> name.</p>
<p>If conditional compilation must be used in mainline platform-independent code, avoid using the system name. Instead, <code>#define</code> a descriptive name in <code><config.h></code>, and test it like this:</p>
<div class="fragment"><div class="line">\#ifdef JACK_USE_MACH_THREADS</div><div class="line"> allocate_mach_serverport(engine, <a class="code" href="simple__client_8c.html#afed7053cd7bdd1cce33dec7213f340ea">client</a>);</div><div class="line"> <a class="code" href="simple__client_8c.html#afed7053cd7bdd1cce33dec7213f340ea">client</a>->running = FALSE;</div><div class="line">\#endif</div></div><!-- fragment --><p>Be sure to place any generic implementation alternative in the <code>#else</code> or use an <code>#ifndef</code>, so no other code needs to know your conditional labels.</p>
<h1><a class="anchor" id="portissues"></a>
Issues Not Addressed</h1>
<ul>
<li>Cross-compilation has not been tested, or even thought through in much detail. The <em>host</em> is the system on which JACK will run. This may differ from the <em>build</em> system doing the compilation. These are selected using the standard <code></code>./configure options <code>–host</code> and <code>–build</code>. Usually, <code></code>./config.guess can print the appropriate canonical name for any system on which it runs.</li>
<li>Platform-specific build tools like Apple's Project Builder are not well-supported. </li>
</ul>
</div></div><!-- contents -->
<!-- start footer part -->
<hr class="footer"/><address class="footer"><small>
Generated by  <a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/>
</a> 1.8.13
</small></address>
</body>
</html>