docs/d8/d4d/_lazy_8h_source.html

   1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
   2 <html xmlns="http://www.w3.org/1999/xhtml">
   3 <head>
   4 <meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
   5 <meta http-equiv="X-UA-Compatible" content="IE=9"/>
   6 <meta name="generator" content="Doxygen 1.8.12"/>
   7 <meta name="viewport" content="width=device-width, initial-scale=1"/>
   8 <title>MuldeR&#39;s Utilities for Qt: include/MUtils/Lazy.h Source File</title>
   9 <link href="../../tabs.css" rel="stylesheet" type="text/css"/>
  10 <script type="text/javascript" src="../../jquery.js"></script>
  11 <script type="text/javascript" src="../../dynsections.js"></script>
  12 <link href="../../search/search.css" rel="stylesheet" type="text/css"/>
  13 <script type="text/javascript" src="../../search/searchdata.js"></script>
  14 <script type="text/javascript" src="../../search/search.js"></script>
  15 <link href="../../doxygen.css" rel="stylesheet" type="text/css" />
  16 </head>
  17 <body>
  18 <div id="top"><!-- do not remove this div, it is closed by doxygen! -->
  19 <div id="titlearea">
  20 <table cellspacing="0" cellpadding="0">
  21  <tbody>
  22  <tr style="height: 56px;">
  23   <td id="projectalign" style="padding-left: 0.5em;">
  24    <div id="projectname">MuldeR&#39;s Utilities for Qt
  25    </div>
  26    <div id="projectbrief">MUtilities</div>
  27   </td>
  28  </tr>
  29  </tbody>
  30 </table>
  31 </div>
  32 <!-- end header part -->
  33 <!-- Generated by Doxygen 1.8.12 -->
  34 <script type="text/javascript">
  35 var searchBox = new SearchBox("searchBox", "../../search",false,'Search');
  36 </script>
  37 <script type="text/javascript" src="../../menudata.js"></script>
  38 <script type="text/javascript" src="../../menu.js"></script>
  39 <script type="text/javascript">
  40 $(function() {
  41   initMenu('../../',true,false,'search.php','Search');
  42   $(document).ready(function() { init_search(); });
  43 });
  44 </script>
  45 <div id="main-nav"></div>
  46 <!-- window showing the filter options -->
  47 <div id="MSearchSelectWindow"
  48      onmouseover="return searchBox.OnSearchSelectShow()"
  49      onmouseout="return searchBox.OnSearchSelectHide()"
  50      onkeydown="return searchBox.OnSearchSelectKey(event)">
  51 </div>
  52
  53 <!-- iframe showing the search results (closed by default) -->
  54 <div id="MSearchResultsWindow">
  55 <iframe src="javascript:void(0)" frameborder="0"
  56         name="MSearchResults" id="MSearchResults">
  57 </iframe>
  58 </div>
  59
  60 <div id="nav-path" class="navpath">
  61   <ul>
  62 <li class="navelem"><a class="el" href="../../dir_d44c64559bbebec7f509842c48db8b23.html">include</a></li><li class="navelem"><a class="el" href="../../dir_b076b53667bc06ebb413a190e197fc7b.html">MUtils</a></li>  </ul>
  63 </div>
  64 </div><!-- top -->
  65 <div class="header">
  66   <div class="headertitle">
  67 <div class="title">Lazy.h</div>  </div>
  68 </div><!--header-->
  69 <div class="contents">
  70 <a href="../../d8/d4d/_lazy_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno">    1</span>&#160;<span class="comment">// MuldeR&#39;s Utilities for Qt</span></div><div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160;<span class="comment">// Copyright (C) 2004-2019 LoRd_MuldeR &lt;MuldeR2@GMX.de&gt;</span></div><div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160;<span class="comment">//</span></div><div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160;<span class="comment">// This library is free software; you can redistribute it and/or</span></div><div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="comment">// modify it under the terms of the GNU Lesser General Public</span></div><div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;<span class="comment">// License as published by the Free Software Foundation; either</span></div><div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;<span class="comment">// version 2.1 of the License, or (at your option) any later version.</span></div><div class="line"><a name="l00009"></a><span class="lineno">    9</span>&#160;<span class="comment">//</span></div><div class="line"><a name="l00010"></a><span class="lineno">   10</span>&#160;<span class="comment">// This library is distributed in the hope that it will be useful,</span></div><div class="line"><a name="l00011"></a><span class="lineno">   11</span>&#160;<span class="comment">// but WITHOUT ANY WARRANTY; without even the implied warranty of</span></div><div class="line"><a name="l00012"></a><span class="lineno">   12</span>&#160;<span class="comment">// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU</span></div><div class="line"><a name="l00013"></a><span class="lineno">   13</span>&#160;<span class="comment">// Lesser General Public License for more details.</span></div><div class="line"><a name="l00014"></a><span class="lineno">   14</span>&#160;<span class="comment">//</span></div><div class="line"><a name="l00015"></a><span class="lineno">   15</span>&#160;<span class="comment">// You should have received a copy of the GNU Lesser General Public</span></div><div class="line"><a name="l00016"></a><span class="lineno">   16</span>&#160;<span class="comment">// License along with this library; if not, write to the Free Software</span></div><div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;<span class="comment">// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA</span></div><div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;<span class="comment">//</span></div><div class="line"><a name="l00019"></a><span class="lineno">   19</span>&#160;<span class="comment">// http://www.gnu.org/licenses/lgpl-2.1.txt</span></div><div class="line"><a name="l00021"></a><span class="lineno">   21</span>&#160;<span class="comment"></span></div><div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;<span class="preprocessor">#pragma once</span></div><div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;</div><div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;<span class="comment">//MUtils</span></div><div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;<span class="preprocessor">#include &lt;<a class="code" href="../../d5/d3b/_global_8h.html">MUtils/Global.h</a>&gt;</span></div><div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;<span class="preprocessor">#include &lt;MUtils/Exception.h&gt;</span></div><div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;</div><div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;<span class="comment">//Qt</span></div><div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;<span class="preprocessor">#include &lt;QThread&gt;</span></div><div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;<span class="preprocessor">#include &lt;QAtomicPointer&gt;</span></div><div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;<span class="preprocessor">#include &lt;QAtomicInt&gt;</span></div><div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;</div><div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;<span class="comment">//CRT</span></div><div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;<span class="preprocessor">#include &lt;functional&gt;</span></div><div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;</div><div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;<span class="keyword">namespace </span><a class="code" href="../../d3/da6/namespace_m_utils.html">MUtils</a></div><div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;{</div><div class="line"><a name="l00050"></a><span class="lineno"><a class="line" href="../../d0/dce/class_m_utils_1_1_lazy.html">   50</a></span>&#160;    <span class="keyword">template</span>&lt;<span class="keyword">typename</span> T&gt; <span class="keyword">class </span><a class="code" href="../../d0/dce/class_m_utils_1_1_lazy.html">Lazy</a></div><div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;    {</div><div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;    <span class="keyword">public</span>:</div><div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;        <a class="code" href="../../d0/dce/class_m_utils_1_1_lazy.html">Lazy</a>(std::function&lt;T*(<span class="keywordtype">void</span>)&gt; &amp;&amp;initializer) : m_initializer(initializer) { }</div><div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;</div><div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;        T&amp; operator*(<span class="keywordtype">void</span>)</div><div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;        {</div><div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;            <span class="keywordflow">return</span> (*getValue());</div><div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;        }</div><div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;</div><div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;        T* operator-&gt;(<span class="keywordtype">void</span>)</div><div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160;        {</div><div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;            <span class="keywordflow">return</span> getValue();</div><div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;        }</div><div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;</div><div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;        <span class="keywordtype">bool</span> initialized()</div><div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;        {</div><div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;            <span class="keywordflow">return</span> (m_state &gt; 1);</div><div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;        }</div><div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;</div><div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;        ~<a class="code" href="../../d0/dce/class_m_utils_1_1_lazy.html">Lazy</a>(<span class="keywordtype">void</span>)</div><div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160;        {</div><div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;            <span class="keywordflow">if</span>(T *<span class="keyword">const</span> value = m_value)</div><div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;            {</div><div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160;                <span class="keyword">delete</span> value;</div><div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160;            }</div><div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;        }</div><div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;</div><div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;    <span class="keyword">protected</span>:</div><div class="line"><a name="l00079"></a><span class="lineno">   79</span>&#160;        __forceinline T* getValue()</div><div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;        {</div><div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160;            T *value;</div><div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;            <span class="keywordflow">while</span> (!(value = m_value))</div><div class="line"><a name="l00083"></a><span class="lineno">   83</span>&#160;            {</div><div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;                <span class="keywordflow">if</span> (m_state.testAndSetOrdered(0, 1))</div><div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;                {</div><div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;                    <span class="keywordflow">if</span> (value = m_initializer())</div><div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;                    {</div><div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;                        m_value.fetchAndStoreOrdered(value);</div><div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;                        m_state.fetchAndStoreOrdered(2);</div><div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;                        <span class="keywordflow">break</span>; <span class="comment">/*success*/</span></div><div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;                    }</div><div class="line"><a name="l00092"></a><span class="lineno">   92</span>&#160;                    m_state.fetchAndStoreOrdered(0);</div><div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160;                    MUTILS_THROW(<span class="stringliteral">&quot;Initializer returned NULL pointer!&quot;</span>);</div><div class="line"><a name="l00094"></a><span class="lineno">   94</span>&#160;                }</div><div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;                QThread::yieldCurrentThread();</div><div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;            }</div><div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160;            <span class="keywordflow">return</span> value;</div><div class="line"><a name="l00098"></a><span class="lineno">   98</span>&#160;        }</div><div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;</div><div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160;    <span class="keyword">private</span>:</div><div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160;        QAtomicPointer&lt;T&gt; m_value;</div><div class="line"><a name="l00102"></a><span class="lineno">  102</span>&#160;        QAtomicInt m_state;</div><div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;        <span class="keyword">const</span> std::function&lt;T*(void)&gt; m_initializer;</div><div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;    };</div><div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;}</div><div class="ttc" id="_global_8h_html"><div class="ttname"><a href="../../d5/d3b/_global_8h.html">Global.h</a></div><div class="ttdoc">This file contains miscellaneous functions that are generally useful for Qt-based applications...</div></div>
  71 <div class="ttc" id="class_m_utils_1_1_lazy_html"><div class="ttname"><a href="../../d0/dce/class_m_utils_1_1_lazy.html">MUtils::Lazy</a></div><div class="ttdoc">Lazy initialization template class. </div><div class="ttdef"><b>Definition:</b> Lazy.h:50</div></div>
  72 <div class="ttc" id="namespace_m_utils_html"><div class="ttname"><a href="../../d3/da6/namespace_m_utils.html">MUtils</a></div><div class="ttdoc">Global MUtils namespace. </div><div class="ttdef"><b>Definition:</b> CPUFeatures.h:37</div></div>
  73 </div><!-- fragment --></div><!-- contents -->
  74 <!-- start footer part -->
  75 <hr class="footer"/><address class="footer"><small>
  76 Generated by &#160;<a href="http://www.doxygen.org/index.html">
  77 <img class="footer" src="../../doxygen.png" alt="doxygen"/>
  78 </a> 1.8.12
  79 </small></address>
  80 </body>
  81 </html>