| <!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 1.8.5"/> |
| <title>Apache Mesos: 3rdparty/libprocess/include/process/once.hpp Source File</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="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 style="padding-left: 0.5em;"> |
| <div id="projectname">Apache Mesos |
| </div> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <!-- end header part --> |
| <!-- Generated by Doxygen 1.8.5 --> |
| <div id="navrow1" class="tabs"> |
| <ul class="tablist"> |
| <li><a href="index.html"><span>Main Page</span></a></li> |
| <li><a href="pages.html"><span>Related Pages</span></a></li> |
| <li><a href="namespaces.html"><span>Namespaces</span></a></li> |
| <li><a href="annotated.html"><span>Classes</span></a></li> |
| <li class="current"><a href="files.html"><span>Files</span></a></li> |
| <li><a href="examples.html"><span>Examples</span></a></li> |
| </ul> |
| </div> |
| <div id="navrow2" class="tabs2"> |
| <ul class="tablist"> |
| <li><a href="files.html"><span>File List</span></a></li> |
| <li><a href="globals.html"><span>File Members</span></a></li> |
| </ul> |
| </div> |
| <div id="nav-path" class="navpath"> |
| <ul> |
| <li class="navelem"><a class="el" href="dir_8cab8f464681f7cc51cee77e79a434cd.html">3rdparty</a></li><li class="navelem"><a class="el" href="dir_043a76de98701f9bddf61b5e98f305ff.html">libprocess</a></li><li class="navelem"><a class="el" href="dir_eac18f7a64f6f8afbd1493ef4e09abdb.html">include</a></li><li class="navelem"><a class="el" href="dir_1894286df79cf582d947dbc4268b06cf.html">process</a></li> </ul> |
| </div> |
| </div><!-- top --> |
| <div class="header"> |
| <div class="headertitle"> |
| <div class="title">once.hpp</div> </div> |
| </div><!--header--> |
| <div class="contents"> |
| <a href="once_8hpp.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">// Licensed under the Apache License, Version 2.0 (the "License");</span></div> |
| <div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment">// you may not use this file except in compliance with the License.</span></div> |
| <div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment">// You may obtain a copy of the License at</span></div> |
| <div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment">//</span></div> |
| <div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment">// http://www.apache.org/licenses/LICENSE-2.0</span></div> |
| <div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment">//</span></div> |
| <div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment">// Unless required by applicable law or agreed to in writing, software</span></div> |
| <div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment">// distributed under the License is distributed on an "AS IS" BASIS,</span></div> |
| <div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment">// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span></div> |
| <div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment">// See the License for the specific language governing permissions and</span></div> |
| <div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment">// limitations under the License</span></div> |
| <div class="line"><a name="l00012"></a><span class="lineno"> 12</span> </div> |
| <div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="preprocessor">#ifndef __PROCESS_ONCE_HPP__</span></div> |
| <div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="preprocessor"></span><span class="preprocessor">#define __PROCESS_ONCE_HPP__</span></div> |
| <div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="preprocessor"></span></div> |
| <div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="preprocessor">#include <condition_variable></span></div> |
| <div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="preprocessor">#include <mutex></span></div> |
| <div class="line"><a name="l00018"></a><span class="lineno"> 18</span> </div> |
| <div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="preprocessor">#include <<a class="code" href="synchronized_8hpp.html">stout/synchronized.hpp</a>></span></div> |
| <div class="line"><a name="l00020"></a><span class="lineno"> 20</span> </div> |
| <div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="keyword">namespace </span><a class="code" href="namespaceos.html#ae19e4161a51b86a1f330f3bf1dc75389">process</a> {</div> |
| <div class="line"><a name="l00022"></a><span class="lineno"> 22</span> </div> |
| <div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="comment">// Provides a _blocking_ abstraction that's useful for performing a</span></div> |
| <div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="comment">// task exactly once.</span></div> |
| <div class="line"><a name="l00025"></a><span class="lineno"><a class="line" href="classprocess_1_1Once.html"> 25</a></span> <span class="keyword">class </span><a class="code" href="classprocess_1_1Once.html">Once</a></div> |
| <div class="line"><a name="l00026"></a><span class="lineno"> 26</span> {</div> |
| <div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="keyword">public</span>:</div> |
| <div class="line"><a name="l00028"></a><span class="lineno"><a class="line" href="classprocess_1_1Once.html#af3c871858c0d2f141238afd52de2643c"> 28</a></span>  <a class="code" href="classprocess_1_1Once.html#af3c871858c0d2f141238afd52de2643c">Once</a>() : started(false), finished(false) {}</div> |
| <div class="line"><a name="l00029"></a><span class="lineno"> 29</span> </div> |
| <div class="line"><a name="l00030"></a><span class="lineno"> 30</span>  <a class="code" href="classprocess_1_1Once.html#a757b5aa045b5833563235eb0d84afa82">~Once</a>() = <span class="keywordflow">default</span>;</div> |
| <div class="line"><a name="l00031"></a><span class="lineno"> 31</span> </div> |
| <div class="line"><a name="l00032"></a><span class="lineno"> 32</span>  <span class="comment">// Returns true if this Once instance has already transitioned to a</span></div> |
| <div class="line"><a name="l00033"></a><span class="lineno"> 33</span>  <span class="comment">// 'done' state (i.e., the action you wanted to perform "once" has</span></div> |
| <div class="line"><a name="l00034"></a><span class="lineno"> 34</span>  <span class="comment">// been completed). Note that this BLOCKS until Once::done has been</span></div> |
| <div class="line"><a name="l00035"></a><span class="lineno"> 35</span>  <span class="comment">// called.</span></div> |
| <div class="line"><a name="l00036"></a><span class="lineno"><a class="line" href="classprocess_1_1Once.html#af60c4d00f5bca3091b20709b038e5ef3"> 36</a></span>  <span class="keywordtype">bool</span> <a class="code" href="classprocess_1_1Once.html#af60c4d00f5bca3091b20709b038e5ef3">once</a>()</div> |
| <div class="line"><a name="l00037"></a><span class="lineno"> 37</span>  {</div> |
| <div class="line"><a name="l00038"></a><span class="lineno"> 38</span>  <span class="keywordtype">bool</span> result = <span class="keyword">false</span>;</div> |
| <div class="line"><a name="l00039"></a><span class="lineno"> 39</span> </div> |
| <div class="line"><a name="l00040"></a><span class="lineno"> 40</span>  <span class="keyword">synchronized</span> (mutex) {</div> |
| <div class="line"><a name="l00041"></a><span class="lineno"> 41</span>  <span class="keywordflow">if</span> (started) {</div> |
| <div class="line"><a name="l00042"></a><span class="lineno"> 42</span>  <span class="keywordflow">while</span> (!finished) {</div> |
| <div class="line"><a name="l00043"></a><span class="lineno"> 43</span>  <a class="code" href="synchronized_8hpp.html#a9d854e5436a64744a231418cde397b05">synchronized_wait</a>(&cond, &mutex);</div> |
| <div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  }</div> |
| <div class="line"><a name="l00045"></a><span class="lineno"> 45</span>  result = <span class="keyword">true</span>;</div> |
| <div class="line"><a name="l00046"></a><span class="lineno"> 46</span>  } <span class="keywordflow">else</span> {</div> |
| <div class="line"><a name="l00047"></a><span class="lineno"> 47</span>  started = <span class="keyword">true</span>;</div> |
| <div class="line"><a name="l00048"></a><span class="lineno"> 48</span>  }</div> |
| <div class="line"><a name="l00049"></a><span class="lineno"> 49</span>  }</div> |
| <div class="line"><a name="l00050"></a><span class="lineno"> 50</span> </div> |
| <div class="line"><a name="l00051"></a><span class="lineno"> 51</span>  <span class="keywordflow">return</span> result;</div> |
| <div class="line"><a name="l00052"></a><span class="lineno"> 52</span>  }</div> |
| <div class="line"><a name="l00053"></a><span class="lineno"> 53</span> </div> |
| <div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  <span class="comment">// Transitions this Once instance to a 'done' state.</span></div> |
| <div class="line"><a name="l00055"></a><span class="lineno"><a class="line" href="classprocess_1_1Once.html#a2b83d07d529fb1028705e5c5bcafab6c"> 55</a></span>  <span class="keywordtype">void</span> <a class="code" href="classprocess_1_1Once.html#a2b83d07d529fb1028705e5c5bcafab6c">done</a>()</div> |
| <div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  {</div> |
| <div class="line"><a name="l00057"></a><span class="lineno"> 57</span>  <span class="keyword">synchronized</span> (mutex) {</div> |
| <div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  <span class="keywordflow">if</span> (started && !finished) {</div> |
| <div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  finished = <span class="keyword">true</span>;</div> |
| <div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  cond.notify_all();</div> |
| <div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  }</div> |
| <div class="line"><a name="l00062"></a><span class="lineno"> 62</span>  }</div> |
| <div class="line"><a name="l00063"></a><span class="lineno"> 63</span>  }</div> |
| <div class="line"><a name="l00064"></a><span class="lineno"> 64</span> </div> |
| <div class="line"><a name="l00065"></a><span class="lineno"> 65</span> <span class="keyword">private</span>:</div> |
| <div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  <span class="comment">// Not copyable, not assignable.</span></div> |
| <div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  <a class="code" href="classprocess_1_1Once.html#af3c871858c0d2f141238afd52de2643c">Once</a>(<span class="keyword">const</span> <a class="code" href="classprocess_1_1Once.html">Once</a>& that);</div> |
| <div class="line"><a name="l00068"></a><span class="lineno"> 68</span>  <a class="code" href="classprocess_1_1Once.html">Once</a>& operator=(<span class="keyword">const</span> <a class="code" href="classprocess_1_1Once.html">Once</a>& that);</div> |
| <div class="line"><a name="l00069"></a><span class="lineno"> 69</span> </div> |
| <div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  std::mutex mutex;</div> |
| <div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  std::condition_variable cond;</div> |
| <div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  <span class="keywordtype">bool</span> started;</div> |
| <div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  <span class="keywordtype">bool</span> finished;</div> |
| <div class="line"><a name="l00074"></a><span class="lineno"> 74</span> };</div> |
| <div class="line"><a name="l00075"></a><span class="lineno"> 75</span> </div> |
| <div class="line"><a name="l00076"></a><span class="lineno"> 76</span> } <span class="comment">// namespace process {</span></div> |
| <div class="line"><a name="l00077"></a><span class="lineno"> 77</span> </div> |
| <div class="line"><a name="l00078"></a><span class="lineno"> 78</span> <span class="preprocessor">#endif // __PROCESS_ONCE_HPP__</span></div> |
| <div class="ttc" id="synchronized_8hpp_html"><div class="ttname"><a href="synchronized_8hpp.html">synchronized.hpp</a></div></div> |
| <div class="ttc" id="synchronized_8hpp_html_a9d854e5436a64744a231418cde397b05"><div class="ttname"><a href="synchronized_8hpp.html#a9d854e5436a64744a231418cde397b05">synchronized_wait</a></div><div class="ttdeci">void synchronized_wait(CV *cv, Lock *lock)</div><div class="ttdoc">Waits on the condition variable associated with &#39;lock&#39; which has already been synchronized. </div></div> |
| <div class="ttc" id="classprocess_1_1Once_html_a757b5aa045b5833563235eb0d84afa82"><div class="ttname"><a href="classprocess_1_1Once.html#a757b5aa045b5833563235eb0d84afa82">process::Once::~Once</a></div><div class="ttdeci">~Once()=default</div></div> |
| <div class="ttc" id="classprocess_1_1Once_html"><div class="ttname"><a href="classprocess_1_1Once.html">process::Once</a></div><div class="ttdef"><b>Definition:</b> once.hpp:25</div></div> |
| <div class="ttc" id="namespaceos_html_ae19e4161a51b86a1f330f3bf1dc75389"><div class="ttname"><a href="namespaceos.html#ae19e4161a51b86a1f330f3bf1dc75389">os::process</a></div><div class="ttdeci">Result< Process > process(pid_t pid)</div><div class="ttdef"><b>Definition:</b> freebsd.hpp:30</div></div> |
| <div class="ttc" id="classprocess_1_1Once_html_af60c4d00f5bca3091b20709b038e5ef3"><div class="ttname"><a href="classprocess_1_1Once.html#af60c4d00f5bca3091b20709b038e5ef3">process::Once::once</a></div><div class="ttdeci">bool once()</div><div class="ttdef"><b>Definition:</b> once.hpp:36</div></div> |
| <div class="ttc" id="classprocess_1_1Once_html_a2b83d07d529fb1028705e5c5bcafab6c"><div class="ttname"><a href="classprocess_1_1Once.html#a2b83d07d529fb1028705e5c5bcafab6c">process::Once::done</a></div><div class="ttdeci">void done()</div><div class="ttdef"><b>Definition:</b> once.hpp:55</div></div> |
| <div class="ttc" id="classprocess_1_1Once_html_af3c871858c0d2f141238afd52de2643c"><div class="ttname"><a href="classprocess_1_1Once.html#af3c871858c0d2f141238afd52de2643c">process::Once::Once</a></div><div class="ttdeci">Once()</div><div class="ttdef"><b>Definition:</b> once.hpp:28</div></div> |
| </div><!-- fragment --></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> 1.8.5 |
| </small></address> |
| </body> |
| </html> |
