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<!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 1.8.14"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <title>Ruby: missing/ffs.c 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 id="projectalign" style="padding-left: 0.5em;"> <div id="projectname">Ruby  <span id="projectnumber">2.1.10p492(2016-04-01revision54464)</span> </div> </td> </tr> </tbody> </table> </div> <!-- end header part --> <!-- Generated by Doxygen 1.8.14 --> <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:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */ $(function() { initMenu('../../',false,false,'search.php','Search'); }); /* @license-end */</script> <div id="main-nav"></div> <div id="nav-path" class="navpath"> <ul> <li class="navelem"><a class="el" href="../../dir_f3bfeebb553c3f6ecfb19202628b4493.html">missing</a></li> </ul> </div> </div><!-- top --> <div class="header"> <div class="headertitle"> <div class="title">ffs.c</div> </div> </div><!--header--> <div class="contents"> <a href="../../de/df2/ffs_8c.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">/* ffs.c - find first set bit */</span></div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment">/* ffs() is defined by Single Unix Specification. */</span></div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> </div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="preprocessor">#include "<a class="code" href="../../d9/d3f/ruby_8h.html">ruby.h</a>"</span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> </div><div class="line"><a name="l00006"></a><span class="lineno"><a class="line" href="../../de/df2/ffs_8c.html#a15b82144d3e24e0f5495a119909d2564"> 6</a></span> <span class="keywordtype">int</span> <a class="code" href="../../de/df2/ffs_8c.html#a15b82144d3e24e0f5495a119909d2564">ffs</a>(<span class="keywordtype">int</span> arg)</div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> {</div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> x = (<span class="keywordtype">unsigned</span> int)arg;</div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span>  <span class="keywordtype">int</span> r;</div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> </div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span>  <span class="keywordflow">if</span> (x == 0)</div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span>  <span class="keywordflow">return</span> 0;</div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> </div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span>  r = 1;</div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> </div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="preprocessor">#if 32 < SIZEOF_INT * CHAR_BIT</span></div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span>  <span class="keywordflow">if</span> ((x & 0xffffffff) == 0) {</div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span>  x >>= 32;</div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span>  r += 32;</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="preprocessor">#endif</span></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="keywordflow">if</span> ((x & 0xffff) == 0) {</div><div class="line"><a name="l00024"></a><span class="lineno"> 24</span>  x >>= 16;</div><div class="line"><a name="l00025"></a><span class="lineno"> 25</span>  r += 16;</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> </div><div class="line"><a name="l00028"></a><span class="lineno"> 28</span>  <span class="keywordflow">if</span> ((x & 0xff) == 0) {</div><div class="line"><a name="l00029"></a><span class="lineno"> 29</span>  x >>= 8;</div><div class="line"><a name="l00030"></a><span class="lineno"> 30</span>  r += 8;</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> </div><div class="line"><a name="l00033"></a><span class="lineno"> 33</span>  <span class="keywordflow">if</span> ((x & 0xf) == 0) {</div><div class="line"><a name="l00034"></a><span class="lineno"> 34</span>  x >>= 4;</div><div class="line"><a name="l00035"></a><span class="lineno"> 35</span>  r += 4;</div><div class="line"><a name="l00036"></a><span class="lineno"> 36</span>  }</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="keywordflow">if</span> ((x & 0x3) == 0) {</div><div class="line"><a name="l00039"></a><span class="lineno"> 39</span>  x >>= 2;</div><div class="line"><a name="l00040"></a><span class="lineno"> 40</span>  r += 2;</div><div class="line"><a name="l00041"></a><span class="lineno"> 41</span>  }</div><div class="line"><a name="l00042"></a><span class="lineno"> 42</span> </div><div class="line"><a name="l00043"></a><span class="lineno"> 43</span>  <span class="keywordflow">if</span> ((x & 0x1) == 0) {</div><div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  x >>= 1;</div><div class="line"><a name="l00045"></a><span class="lineno"> 45</span>  r += 1;</div><div class="line"><a name="l00046"></a><span class="lineno"> 46</span>  }</div><div class="line"><a name="l00047"></a><span class="lineno"> 47</span> </div><div class="line"><a name="l00048"></a><span class="lineno"> 48</span>  <span class="keywordflow">return</span> r;</div><div class="line"><a name="l00049"></a><span class="lineno"> 49</span> }</div><div class="ttc" id="ruby_8h_html"><div class="ttname"><a href="../../d9/d3f/ruby_8h.html">ruby.h</a></div></div> <div class="ttc" id="ffs_8c_html_a15b82144d3e24e0f5495a119909d2564"><div class="ttname"><a href="../../de/df2/ffs_8c.html#a15b82144d3e24e0f5495a119909d2564">ffs</a></div><div class="ttdeci">int ffs(int arg)</div><div class="ttdef"><b>Definition:</b> <a href="../../de/df2/ffs_8c_source.html#l00006">ffs.c:6</a></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> 1.8.14 </small></address> </body> </html>
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