blob: 4798e04d9a1fe2902a99bdae1d62f62127998788 [file] [log] [blame] [edit]
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en-US">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=11"/>
<meta name="generator" content="Doxygen 1.12.0"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>lwIP: Critical sections</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>
<script type="text/javascript" src="clipboard.js"></script>
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="navtreedata.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript" src="cookie.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 id="projectrow">
<td id="projectalign">
<div id="projectname">lwIP<span id="projectnumber">&#160;2.1.3</span>
</div>
<div id="projectbrief">Lightweight IP stack</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.12.0 -->
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
var searchBox = new SearchBox("searchBox", "search/",'.html');
/* @license-end */
</script>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
$(function() { codefold.init(0); });
/* @license-end */
</script>
<script type="text/javascript" src="menudata.js"></script>
<script type="text/javascript" src="menu.js"></script>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
$(function() {
initMenu('',true,false,'search.php','Search',true);
$(function() { init_search(); });
});
/* @license-end */
</script>
<div id="main-nav"></div>
</div><!-- top -->
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
<div id="nav-sync" class="sync"></div>
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
$(function(){initNavTree('group__sys__prot.html',''); initResizable(true); });
/* @license-end */
</script>
<div id="doc-content">
<!-- 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">
<div id="MSearchResults">
<div class="SRPage">
<div id="SRIndex">
<div id="SRResults"></div>
<div class="SRStatus" id="Loading">Loading...</div>
<div class="SRStatus" id="Searching">Searching...</div>
<div class="SRStatus" id="NoMatches">No Matches</div>
</div>
</div>
</div>
</div>
<div class="header">
<div class="summary">
<a href="#define-members">Macros</a> </div>
<div class="headertitle"><div class="title">Critical sections<div class="ingroups"><a class="el" href="group__lwip.html">lwIP</a> &raquo; <a class="el" href="group__sys__layer.html">Porting (system abstraction layer)</a></div></div></div>
</div><!--header-->
<div class="contents">
<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="define-members" name="define-members"></a>
Macros</h2></td></tr>
<tr class="memitem:ga945395fa326214fc9736487242710a90" id="r_ga945395fa326214fc9736487242710a90"><td class="memItemLeft" align="right" valign="top">#define&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="#ga945395fa326214fc9736487242710a90">SYS_ARCH_DECL_PROTECT</a>(lev)</td></tr>
<tr class="separator:ga945395fa326214fc9736487242710a90"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ga3d0e48feafd378e9c26c64567ecd8bab" id="r_ga3d0e48feafd378e9c26c64567ecd8bab"><td class="memItemLeft" align="right" valign="top">#define&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="#ga3d0e48feafd378e9c26c64567ecd8bab">SYS_ARCH_PROTECT</a>(lev)</td></tr>
<tr class="separator:ga3d0e48feafd378e9c26c64567ecd8bab"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ga2f48e97047945642ddeb27e65bf4ffe2" id="r_ga2f48e97047945642ddeb27e65bf4ffe2"><td class="memItemLeft" align="right" valign="top">#define&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="#ga2f48e97047945642ddeb27e65bf4ffe2">SYS_ARCH_UNPROTECT</a>(lev)</td></tr>
<tr class="separator:ga2f48e97047945642ddeb27e65bf4ffe2"><td class="memSeparator" colspan="2">&#160;</td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<p>Used to protect short regions of code against concurrent access.</p><ul>
<li>Your system is a bare-metal system (probably with an RTOS) and interrupts are under your control: Implement this as LockInterrupts() / UnlockInterrupts()</li>
<li>Your system uses an RTOS with deferred interrupt handling from a worker thread: Implement as a global mutex or lock/unlock scheduler</li>
<li>Your system uses a high-level OS with e.g. POSIX signals: Implement as a global mutex </li>
</ul>
<h2 class="groupheader">Macro Definition Documentation</h2>
<a id="ga945395fa326214fc9736487242710a90" name="ga945395fa326214fc9736487242710a90"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga945395fa326214fc9736487242710a90">&#9670;&#160;</a></span>SYS_ARCH_DECL_PROTECT</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">#define SYS_ARCH_DECL_PROTECT</td>
<td>(</td>
<td class="paramtype"></td> <td class="paramname"><span class="paramname"><em>lev</em></span></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<b>Value:</b><div class="fragment"><div class="line">sys_prot_t lev</div>
</div><!-- fragment --><p>SYS_LIGHTWEIGHT_PROT define SYS_LIGHTWEIGHT_PROT in lwipopts.h if you want inter-task protection for certain critical regions during buffer allocation, deallocation and memory allocation and deallocation.</p>
<p>SYS_ARCH_DECL_PROTECT declare a protection variable. This macro will default to defining a variable of type sys_prot_t. If a particular port needs a different implementation, then this macro may be defined in sys_arch.h. </p>
</div>
</div>
<a id="ga3d0e48feafd378e9c26c64567ecd8bab" name="ga3d0e48feafd378e9c26c64567ecd8bab"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga3d0e48feafd378e9c26c64567ecd8bab">&#9670;&#160;</a></span>SYS_ARCH_PROTECT</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">#define SYS_ARCH_PROTECT</td>
<td>(</td>
<td class="paramtype"></td> <td class="paramname"><span class="paramname"><em>lev</em></span></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<b>Value:</b><div class="fragment"><div class="line">lev = sys_arch_protect()</div>
</div><!-- fragment --><p>SYS_ARCH_PROTECT Perform a "fast" protect. This could be implemented by disabling interrupts for an embedded system or by using a semaphore or mutex. The implementation should allow calling SYS_ARCH_PROTECT when already protected. The old protection level is returned in the variable "lev". This macro will default to calling the sys_arch_protect() function which should be implemented in sys_arch.c. If a particular port needs a different implementation, then this macro may be defined in sys_arch.h </p>
</div>
</div>
<a id="ga2f48e97047945642ddeb27e65bf4ffe2" name="ga2f48e97047945642ddeb27e65bf4ffe2"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga2f48e97047945642ddeb27e65bf4ffe2">&#9670;&#160;</a></span>SYS_ARCH_UNPROTECT</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">#define SYS_ARCH_UNPROTECT</td>
<td>(</td>
<td class="paramtype"></td> <td class="paramname"><span class="paramname"><em>lev</em></span></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<b>Value:</b><div class="fragment"><div class="line">sys_arch_unprotect(lev)</div>
</div><!-- fragment --><p>SYS_ARCH_UNPROTECT Perform a "fast" set of the protection level to "lev". This could be implemented by setting the interrupt level to "lev" within the MACRO or by using a semaphore or mutex. This macro will default to calling the sys_arch_unprotect() function which should be implemented in sys_arch.c. If a particular port needs a different implementation, then this macro may be defined in sys_arch.h </p>
</div>
</div>
</div><!-- contents -->
</div><!-- doc-content -->
<!-- start footer part -->
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="footer">Generated by <a href="https://www.doxygen.org/index.html"><img class="footer" src="doxygen.svg" width="104" height="31" alt="doxygen"/></a> 1.12.0 </li>
</ul>
</div>
</body>
</html>