1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Class fixedsize_stack</title> 5<link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../index.html" title="Chapter 1. Context"> 8<link rel="up" href="../stack.html" title="Stack allocation"> 9<link rel="prev" href="pooled_fixedsize.html" title="Class pooled_fixedsize_stack"> 10<link rel="next" href="segmented.html" title="Class segmented_stack"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="pooled_fixedsize.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../stack.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="segmented.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="context.stack.fixedsize"></a><a class="link" href="fixedsize.html" title="Class fixedsize_stack">Class <span class="emphasis"><em>fixedsize_stack</em></span></a> 28</h3></div></div></div> 29<p> 30 <span class="bold"><strong>Boost.Context</strong></span> provides the class <span class="emphasis"><em>fixedsize_stack</em></span> 31 which models the <span class="emphasis"><em>stack-allocator concept</em></span>. In contrast 32 to <span class="emphasis"><em>protected_fixedsize_stack</em></span> it does not append a guard 33 page at the end of each stack. The memory is simply managed by <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">malloc</span><span class="special">()</span></code> and <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">free</span><span class="special">()</span></code>. 34 </p> 35<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">context</span><span class="special">/</span><span class="identifier">fixedsize_stack</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 36 37<span class="keyword">template</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">traitsT</span> <span class="special">></span> 38<span class="keyword">struct</span> <span class="identifier">basic_fixedsize_stack</span> <span class="special">{</span> 39 <span class="keyword">typedef</span> <span class="identifier">traitT</span> <span class="identifier">traits_type</span><span class="special">;</span> 40 41 <span class="identifier">basic_fixesize_stack</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">size</span> <span class="special">=</span> <span class="identifier">traits_type</span><span class="special">::</span><span class="identifier">default_size</span><span class="special">());</span> 42 43 <span class="identifier">stack_context</span> <span class="identifier">allocate</span><span class="special">();</span> 44 45 <span class="keyword">void</span> <span class="identifier">deallocate</span><span class="special">(</span> <span class="identifier">stack_context</span> <span class="special">&);</span> 46<span class="special">}</span> 47 48<span class="keyword">typedef</span> <span class="identifier">basic_fixedsize_stack</span><span class="special"><</span> <span class="identifier">stack_traits</span> <span class="special">></span> <span class="identifier">fixedsize_stack</span><span class="special">;</span> 49</pre> 50<h5> 51<a name="context.stack.fixedsize.h0"></a> 52 <span class="phrase"><a name="context.stack.fixedsize._code__phrase_role__identifier__stack_context__phrase___phrase_role__identifier__allocate__phrase__phrase_role__special______phrase___code_"></a></span><a class="link" href="fixedsize.html#context.stack.fixedsize._code__phrase_role__identifier__stack_context__phrase___phrase_role__identifier__allocate__phrase__phrase_role__special______phrase___code_"><code class="computeroutput"><span class="identifier">stack_context</span> <span class="identifier">allocate</span><span class="special">()</span></code></a> 53 </h5> 54<div class="variablelist"> 55<p class="title"><b></b></p> 56<dl class="variablelist"> 57<dt><span class="term">Preconditions:</span></dt> 58<dd><p> 59 <code class="computeroutput"><span class="identifier">traits_type</span><span class="special">::</span><span class="identifier">minimum</span><span class="special">:</span><span class="identifier">size</span><span class="special">()</span> 60 <span class="special"><=</span> <span class="identifier">size</span></code> 61 and <code class="computeroutput"><span class="special">!</span> <span class="identifier">traits_type</span><span class="special">::</span><span class="identifier">is_unbounded</span><span class="special">()</span> <span class="special">&&</span> 62 <span class="special">(</span> <span class="identifier">traits_type</span><span class="special">::</span><span class="identifier">maximum</span><span class="special">:</span><span class="identifier">size</span><span class="special">()</span> <span class="special">>=</span> <span class="identifier">size</span><span class="special">)</span></code>. 63 </p></dd> 64<dt><span class="term">Effects:</span></dt> 65<dd><p> 66 Allocates memory of at least <code class="computeroutput"><span class="identifier">size</span></code> 67 Bytes and stores a pointer to the stack and its actual size in <code class="computeroutput"><span class="identifier">sctx</span></code>. Depending on the architecture 68 (the stack grows downwards/upwards) the stored address is the highest/lowest 69 address of the stack. 70 </p></dd> 71</dl> 72</div> 73<h5> 74<a name="context.stack.fixedsize.h1"></a> 75 <span class="phrase"><a name="context.stack.fixedsize._code__phrase_role__keyword__void__phrase___phrase_role__identifier__deallocate__phrase__phrase_role__special_____phrase___phrase_role__identifier__stack_context__phrase___phrase_role__special___amp___phrase___phrase_role__identifier__sctx__phrase__phrase_role__special_____phrase___code_"></a></span><a class="link" href="fixedsize.html#context.stack.fixedsize._code__phrase_role__keyword__void__phrase___phrase_role__identifier__deallocate__phrase__phrase_role__special_____phrase___phrase_role__identifier__stack_context__phrase___phrase_role__special___amp___phrase___phrase_role__identifier__sctx__phrase__phrase_role__special_____phrase___code_"><code class="computeroutput"><span class="keyword">void</span> <span class="identifier">deallocate</span><span class="special">(</span> <span class="identifier">stack_context</span> 76 <span class="special">&</span> <span class="identifier">sctx</span><span class="special">)</span></code></a> 77 </h5> 78<div class="variablelist"> 79<p class="title"><b></b></p> 80<dl class="variablelist"> 81<dt><span class="term">Preconditions:</span></dt> 82<dd><p> 83 <code class="computeroutput"><span class="identifier">sctx</span><span class="special">.</span><span class="identifier">sp</span></code> is valid, <code class="computeroutput"><span class="identifier">traits_type</span><span class="special">::</span><span class="identifier">minimum</span><span class="special">:</span><span class="identifier">size</span><span class="special">()</span> <span class="special"><=</span> <span class="identifier">sctx</span><span class="special">.</span><span class="identifier">size</span></code> and <code class="computeroutput"><span class="special">!</span> 84 <span class="identifier">traits_type</span><span class="special">::</span><span class="identifier">is_unbounded</span><span class="special">()</span> 85 <span class="special">&&</span> <span class="special">(</span> 86 <span class="identifier">traits_type</span><span class="special">::</span><span class="identifier">maximum</span><span class="special">:</span><span class="identifier">size</span><span class="special">()</span> 87 <span class="special">>=</span> <span class="identifier">sctx</span><span class="special">.</span><span class="identifier">size</span><span class="special">)</span></code>. 88 </p></dd> 89<dt><span class="term">Effects:</span></dt> 90<dd><p> 91 Deallocates the stack space. 92 </p></dd> 93</dl> 94</div> 95</div> 96<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 97<td align="left"></td> 98<td align="right"><div class="copyright-footer">Copyright © 2014 Oliver Kowalke<p> 99 Distributed under the Boost Software License, Version 1.0. (See accompanying 100 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 101 </p> 102</div></td> 103</tr></table> 104<hr> 105<div class="spirit-nav"> 106<a accesskey="p" href="pooled_fixedsize.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../stack.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="segmented.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 107</div> 108</body> 109</html> 110
