<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html><head><meta http-equiv="Content-Type" content="text/html;charset=UTF-8"> <title>Apache Portable Runtime Utility Library: Optional Functions</title> <link href="doxygen.css" rel="stylesheet" type="text/css"> <link href="tabs.css" rel="stylesheet" type="text/css"> </head><body> <!-- Generated by Doxygen 1.5.4 --> <div class="tabs"> <ul> <li><a href="index.html"><span>Main Page</span></a></li> <li><a href="modules.html"><span>Modules</span></a></li> <li><a href="namespaces.html"><span>Namespaces</span></a></li> <li><a href="annotated.html"><span>Data Structures</span></a></li> <li><a href="files.html"><span>Files</span></a></li> <li><a href="pages.html"><span>Related Pages</span></a></li> </ul> </div> <h1>Optional Functions<br> <small> [<a class="el" href="group___a_p_r___util.html">APR Utility Functions</a>]</small> </h1><table border="0" cellpadding="0" cellspacing="0"> <tr><td></td></tr> <tr><td colspan="2"><br><h2>Defines</h2></td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___a_p_r___util___opt.html#g987fcf75505450f1b4ff9d7b3a7ff5d3">APR_OPTIONAL_FN_TYPE</a>(name) apr_OFN_##name##_t</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___a_p_r___util___opt.html#gf3ff372e28978d4ce0be7517ca2fddbd">APR_DECLARE_OPTIONAL_FN</a>(ret, name, args) typedef ret (APR_OPTIONAL_FN_TYPE(name)) args</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___a_p_r___util___opt.html#gb611deabd6e78b5f666071e8cbdcc736">APR_REGISTER_OPTIONAL_FN</a>(name)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___a_p_r___util___opt.html#g35f2df25ca06248d2fdd3e7463446418">APR_RETRIEVE_OPTIONAL_FN</a>(name) (APR_OPTIONAL_FN_TYPE(name) *)apr_dynamic_fn_retrieve(#name)</td></tr> <tr><td colspan="2"><br><h2>Typedefs</h2></td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">typedef void( </td><td class="memItemRight" valign="bottom"><a class="el" href="group___a_p_r___util___opt.html#g35e08c2dbf593e3dc5a2cb0fdc8cd637">apr_opt_fn_t</a> )(void)</td></tr> <tr><td colspan="2"><br><h2>Functions</h2></td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group___a_p_r___util___opt.html#ga9c7d3cc32128521274543c384e9698d">apr_dynamic_fn_register</a> (const char *szName, <a class="el" href="group___a_p_r___util___opt.html#g35e08c2dbf593e3dc5a2cb0fdc8cd637">apr_opt_fn_t</a> *pfn)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="g1ecfa6a6ced7332d03b5867735a5e49d"></a><!-- doxytag: member="APR_Util_Opt::apr_dynamic_fn_retrieve" ref="g1ecfa6a6ced7332d03b5867735a5e49d" args="(const char *szName)" --> <a class="el" href="group___a_p_r___util___opt.html#g35e08c2dbf593e3dc5a2cb0fdc8cd637">apr_opt_fn_t</a> * </td><td class="memItemRight" valign="bottom"><b>apr_dynamic_fn_retrieve</b> (const char *szName)</td></tr> </table> <hr><a name="_details"></a><h2>Detailed Description</h2> Typesafe registration and retrieval of functions that may not be present (i.e. functions exported by optional modules) <hr><h2>Define Documentation</h2> <a class="anchor" name="gf3ff372e28978d4ce0be7517ca2fddbd"></a><!-- doxytag: member="apr_optional.h::APR_DECLARE_OPTIONAL_FN" ref="gf3ff372e28978d4ce0be7517ca2fddbd" args="(ret, name, args)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define APR_DECLARE_OPTIONAL_FN </td> <td>(</td> <td class="paramtype">ret, <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">name, <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">args </td> <td class="paramname"> </td> <td> ) </td> <td width="100%"> typedef ret (APR_OPTIONAL_FN_TYPE(name)) args</td> </tr> </table> </div> <div class="memdoc"> <p> Declare an optional function. <dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td valign="top"></td><td valign="top"><em>ret</em> </td><td>The return type of the function </td></tr> <tr><td valign="top"></td><td valign="top"><em>name</em> </td><td>The name of the function </td></tr> <tr><td valign="top"></td><td valign="top"><em>args</em> </td><td>The function arguments (including brackets) </td></tr> </table> </dl> </div> </div><p> <a class="anchor" name="g987fcf75505450f1b4ff9d7b3a7ff5d3"></a><!-- doxytag: member="apr_optional.h::APR_OPTIONAL_FN_TYPE" ref="g987fcf75505450f1b4ff9d7b3a7ff5d3" args="(name)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define APR_OPTIONAL_FN_TYPE </td> <td>(</td> <td class="paramtype">name </td> <td class="paramname"> </td> <td> ) </td> <td width="100%"> apr_OFN_##name##_t</td> </tr> </table> </div> <div class="memdoc"> <p> The type of an optional function. <dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td valign="top"></td><td valign="top"><em>name</em> </td><td>The name of the function </td></tr> </table> </dl> </div> </div><p> <a class="anchor" name="gb611deabd6e78b5f666071e8cbdcc736"></a><!-- doxytag: member="apr_optional.h::APR_REGISTER_OPTIONAL_FN" ref="gb611deabd6e78b5f666071e8cbdcc736" args="(name)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define APR_REGISTER_OPTIONAL_FN </td> <td>(</td> <td class="paramtype">name </td> <td class="paramname"> </td> <td> ) </td> <td width="100%"></td> </tr> </table> </div> <div class="memdoc"> <p> <b>Value:</b><div class="fragment"><pre class="fragment"><span class="keywordflow">do</span> { \ <a class="code" href="group___a_p_r___util___opt.html#g987fcf75505450f1b4ff9d7b3a7ff5d3">APR_OPTIONAL_FN_TYPE</a>(name) *apu__opt = name; \ <a class="code" href="group___a_p_r___util___opt.html#ga9c7d3cc32128521274543c384e9698d">apr_dynamic_fn_register</a>(#name,(<a class="code" href="group___a_p_r___util___opt.html#g35e08c2dbf593e3dc5a2cb0fdc8cd637">apr_opt_fn_t</a> *)apu__opt); \ } <span class="keywordflow">while</span> (0) </pre></div>Register an optional function. This can be later retrieved, type-safely, by name. Like all global functions, the name must be unique. Note that, confusingly but correctly, the function itself can be static! <dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td valign="top"></td><td valign="top"><em>name</em> </td><td>The name of the function </td></tr> </table> </dl> </div> </div><p> <a class="anchor" name="g35f2df25ca06248d2fdd3e7463446418"></a><!-- doxytag: member="apr_optional.h::APR_RETRIEVE_OPTIONAL_FN" ref="g35f2df25ca06248d2fdd3e7463446418" args="(name)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define APR_RETRIEVE_OPTIONAL_FN </td> <td>(</td> <td class="paramtype">name </td> <td class="paramname"> </td> <td> ) </td> <td width="100%"> (APR_OPTIONAL_FN_TYPE(name) *)apr_dynamic_fn_retrieve(#name)</td> </tr> </table> </div> <div class="memdoc"> <p> Retrieve an optional function. Returns NULL if the function is not present. <dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td valign="top"></td><td valign="top"><em>name</em> </td><td>The name of the function </td></tr> </table> </dl> </div> </div><p> <hr><h2>Typedef Documentation</h2> <a class="anchor" name="g35e08c2dbf593e3dc5a2cb0fdc8cd637"></a><!-- doxytag: member="apr_optional.h::apr_opt_fn_t" ref="g35e08c2dbf593e3dc5a2cb0fdc8cd637" args=")(void)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">typedef void( <a class="el" href="group___a_p_r___util___opt.html#g35e08c2dbf593e3dc5a2cb0fdc8cd637">apr_opt_fn_t</a>)(void) </td> </tr> </table> </div> <div class="memdoc"> <p> XXX: This doesn't belong here, then! Private function! DO NOT USE! </div> </div><p> <hr><h2>Function Documentation</h2> <a class="anchor" name="ga9c7d3cc32128521274543c384e9698d"></a><!-- doxytag: member="apr_optional.h::apr_dynamic_fn_register" ref="ga9c7d3cc32128521274543c384e9698d" args="(const char *szName, apr_opt_fn_t *pfn)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">void apr_dynamic_fn_register </td> <td>(</td> <td class="paramtype">const char * </td> <td class="paramname"> <em>szName</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="group___a_p_r___util___opt.html#g35e08c2dbf593e3dc5a2cb0fdc8cd637">apr_opt_fn_t</a> * </td> <td class="paramname"> <em>pfn</em></td><td> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td><td width="100%"></td> </tr> </table> </div> <div class="memdoc"> <p> </div> </div><p> <hr size="1"><address style="text-align: right;"><small>Generated on Thu Jan 24 02:22:55 2008 for Apache Portable Runtime Utility Library by <a href="http://www.doxygen.org/index.html"> <img src="doxygen.png" alt="doxygen" align="middle" border="0"></a> 1.5.4 </small></address> </body> </html>