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8 <title>Developing modules for the Apache HTTP Server 2.4 - Apache HTTP Server</title>
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14 <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
15 <p class="apache">Apache HTTP Server Version 2.5</p>
16 <img alt="" src="../images/feather.gif" /></div>
17 <div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
19 <a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.5</a> > <a href="./">Developer</a></div><div id="page-content"><div id="preamble"><h1>Developing modules for the Apache HTTP Server 2.4</h1>
21 <p><span>Available Languages: </span><a href="../en/developer/modguide.html" title="English"> en </a></p>
24 <p>This document explains how you can develop modules for the Apache HTTP Server 2.4</p>
26 <div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#introduction">Introduction</a></li>
27 <li><img alt="" src="../images/down.gif" /> <a href="#basics">Defining a module</a></li>
28 <li><img alt="" src="../images/down.gif" /> <a href="#hooking">Getting started: Hooking into Apache</a></li>
29 <li><img alt="" src="../images/down.gif" /> <a href="#handling">Building a handler</a></li>
30 <li><img alt="" src="../images/down.gif" /> <a href="#configuration">Adding configuration options</a></li>
31 <li><img alt="" src="../images/down.gif" /> <a href="#context">Context aware configurations</a></li>
32 <li><img alt="" src="../images/down.gif" /> <a href="#summary">Summing up</a></li>
33 <li><img alt="" src="../images/down.gif" /> <a href="#snippets">Some useful snippets of code</a></li>
34 </ul><h3>See also</h3><ul class="seealso"><li><a href="request.html">Request Processing in Apache 2.4</a></li><li><a href="hooks.html">Apache 2.x Hook Functions</a></li></ul></div>
35 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
37 <h2><a name="introduction" id="introduction">Introduction</a></h2>
38 <h3><a name="what" id="what">What we will be discussing in this document</a></h3>
40 This document will discuss how you can easily create modules for the Apache HTTP Server 2.4 ("Apache"),
41 by exploring an example module called <code>mod_example</code>. In the first part of this document, the purpose of this
42 module will be to calculate and print out various digest values for existing files on your web server, whenever we
43 access the URL <code>http://hostname/filename.sum</code>. For instance, if we want to know the MD5 digest value of the file
44 located at <code>http://www.example.com/index.html</code>, we would visit <code>http://www.example.com/index.html.sum</code>.
47 In the second part of this document, which deals with configuration directive and context awareness, we will be looking at
48 a module that simply write out its own configuration to the client.
51 <h3><a name="prerequisites" id="prerequisites">Prerequisites</a></h3>
53 First and foremost, you are expected to have a basic knowledge of how the C programming language works. In most cases,
54 we will try to be as pedagogical as possible and link to documents describing the functions used in the examples,
55 but there are also many cases where it is necessary to either just assume that "it works" or do some digging youself
56 into what the hows and whys of various function calls.
59 Lastly, you will need to have a basic understanding of how modules are loaded and configured in Apache, as well as
60 how to get the headers for Apache if you do not have them already, as these are needed for compiling new modules.
63 <h3><a name="compiling" id="compiling">Compiling your module</a></h3>
65 To compile the source code we are building in this document, we will be using <a href="../programs/apxs.html">APXS</a>.
66 Assuming your source file is called mod_example.c, compiling, installing and activating the module is as simple as:
67 <div class="example"><pre>
68 apxs -i -a -c mod_example.c
72 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
74 <h2><a name="basics" id="basics">Defining a module</a></h2>
75 <img src="../images/build_a_mod_3.png" /><br />
76 <p>Every module starts with the same declaration, or name tag if you will, that defines a module as <em>a separate entity within Apache</em>:
80 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
81 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
82 <code style="color:#806030; ">{</code>
83 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
84 create_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
85 merge_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
86 create_svr_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
87 merge_svr_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
88 directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
89 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
90 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
95 This bit of code lets Apache know that we have now registered a new module in the system,
96 and that its name is <code>example_module</code>. The name of the module is used primarilly
99 <li>Letting Apache know how to load the module using the LoadModule</li>
100 <li>Setting up a namespace for the module to use in configurations</li>
102 For now, we're only concerned with the first purpose of the module name,
103 which comes into play when we need to load the module:<br />
104 <div class="example"><pre><a href="../mod/mod_so.html#LoadModule">LoadModule</a> example_module modules/mod_example.so</pre></div>
105 In essence, this tells Apache to open up <code>mod_example.so</code> and look for a module
106 called <code>example_module</code>.
109 Within this name tag of ours is also a bunch of references to how we would like to handle things:
110 Which directives do we respond to in a configuration file or .htaccess, how do we operate
111 within specific contexts, and what handlers are we interested in registering with the Apache
112 service. We'll return to all these elements later in this document.
114 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
115 <div class="section">
116 <h2><a name="hooking" id="hooking">Getting started: Hooking into Apache</a></h2>
117 <h3><a name="hook_intro" id="hook_intro">An introduction to hooks</a></h3>
119 When handling requests in Apache, the first thing you will need to do is create a hook into
120 the request handling process. A hook is essentially a message telling Apache that you are
121 willing to either serve or at least take a glance at certain requests given by clients. All
122 handlers, whether it's mod_rewrite, mod_authn_*, mod_proxy and so on, are hooked into specific
123 parts of the request process. As you are probably aware, modules serve different purposes; Some
124 are authentication/authorization handlers, others are file or script handlers while some third
125 modules rewrite URIs or proxies content. Furthermore, in the end, it is up to the user of Apache
126 how and when each module will come into place. Thus, Apache itself does not presume to know
127 which module is responsible for handling a specific request, and will ask each module whether
128 they have an interest in a given request or not. It is then up to each module to either gently
129 decline serving a request, accept serving it or flat out deny the request from being served,
130 as authentication/authorization modules do: <br />
131 <img src="../images/build_a_mod_2.png" /><br />
132 To make it a bit easier for handlers such as our mod_example to know whether the client is
133 requesting content we should handle or not, Apache has directives for hinting to modules whether
134 their assistance is needed or not. Two of these are <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> and <code class="directive"><a href="../mod/core.html#sethandler">SetHandler</a></code>.
135 Let's take a look at an example using <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code>.
136 In our example case, we want every request ending with .sum to be served by <code>mod_example</code>,
137 so we'll add a configuration directive that tells Apache to do just that:
138 <div class="example"><pre>
139 AddHandler example-handler .sum
141 What this tells Apache is the following: <em>Whenever we receive a request for a URI ending in .sum,
142 we are to let all modules know that we are looking for whoever goes by the name of "example-handler"
143 </em>. Thus, when a request is being served that ends in .sum, Apache will let all modules know, that
144 this request should be served by "example-handler". As you will see later, when we start
145 building mod_example, we will check for this handler tag relayed by <code>AddHandler</code> and
146 reply to Apache based on the value of this tag.
149 <h3><a name="hook_declaration" id="hook_declaration">Hooking into httpd</a></h3>
151 To begin with, we only want to create a simple handler, that replies to the client browser
152 when a specific URL is requested, so we won't bother setting up configuration handlers and
153 directives just yet. Our initial module definition will look like this:<br />
157 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
158 module AP_MODULE_DECLARE_DATA example_module =
160 STANDARD20_MODULE_STUFF,
161 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
162 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
163 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
164 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
165 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
166 <code style="color:#800040; ">register_hooks</code> <code style="color:#c34e00; "><code style="color:#c34e00; ">/* Our hook registering function */</code></code>
172 This lets Apache know that we are not interesting in anything fancy, we just want to hook onto
173 the requests and possibly handle some of them.
176 The reference in our example declaration, <code>register_hooks</code> is the name of a function
177 we will create to manage how we hook onto the request process. In this example module, the function
178 has just one purpose; To create a simple hook that gets called after all the rewrites, access
179 control etc has been handled. Thus, we will let Apache know, that we want to hook into its process
180 as one of the last modules:
184 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
185 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">void</code> register_hooks<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">)</code>
186 <code style="color:#806030; ">{</code>
187 <code style="color:#c34e00; ">/* Create a hook in the request handler, so we get called when a request arrives */</code>
188 <code style="color:#800040; ">ap_hook_handler</code><code style="color:#806030; ">(</code>example_handler<code style="color:#806030; ">,</code> <code style="color:#7f0055; font-weight:bold; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#7f0055; font-weight:bold; ">NULL</code><code style="color:#806030; ">,</code> APR_HOOK_LAST<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
189 <code style="color:#806030; ">}</code>
194 The <code>example_handler</code> reference is the function that will handle the request. We will
195 discuss how to create a handler in the next chapter.
198 <h3><a name="hook_others" id="hook_others">Other useful hooks</a></h3>
200 Hooking into the request handling phase is but one of many hooks that you can create. Some other ways of hooking are:
202 <li><code>ap_hook_child_init</code>: Place a hook that executes when a child process is spawned (commonly used for initializing modules after Apache has forked)</li>
203 <li><code>ap_hook_pre_config</code>: Place a hook that executes before any configuration data has been read (very early hook)</li>
204 <li><code>ap_hook_post_config</code>: Place a hook that executes after configuration has been parsed, but before Apache has forked</li>
205 <li><code>ap_hook_translate_name</code>: Place a hook that executes when a URI needs to be translated into a filename on the server (think <code>mod_rewrite</code>)</li>
209 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
210 <div class="section">
211 <h2><a name="handling" id="handling">Building a handler</a></h2>
213 A handler is essentially a function that receives a callback when a request to Apache is made.
214 It is passed a record of the current request (how it was made, which headers and requests were
215 passed along, who's giving the request and so on), and is put in charge of either telling
216 Apache that it's not interested in the request or handle the request with the tools provided.
218 <h3><a name="simple_handler" id="simple_handler">A simple "Hello, world!" handler</a></h3>
219 Let's start off by making a very simple request handler that does the following: <br />
221 <li>Check that this is a request that should be served by "example-handler"</li>
222 <li>Set the content type of our output to <code>text/html</code></li>
223 <li>Write "Hello, world!" back to the client browser</li>
224 <li>Let Apache know that we took care of this request and everything went fine</li>
226 In C code, our example handler will now look like this:<br />
230 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
231 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
232 <code style="color:#806030; ">{</code>
233 <code style="color:#c34e00; ">/* First off, we need to check if this is a call for the "example-handler" handler.</code>
234 <code style="color:#c34e00; "> * If it is, we accept it and do our things, if not, we simply return DECLINED,</code>
235 <code style="color:#c34e00; "> * and Apache will try somewhere else.</code>
236 <code style="color:#c34e00; "> */</code>
237 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code> <code style="color:#806030; ">|</code><code style="color:#806030; ">|</code> <code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">example-handler</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#806030; ">(</code>DECLINED<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
239 <code style="color:#c34e00; ">/* Now that we are handling this request, we'll write out "Hello, world!" to the client.</code>
240 <code style="color:#c34e00; "> * To do so, we must first set the appropriate content type, followed by our output.</code>
241 <code style="color:#c34e00; "> */</code>
242 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#gaa2f8412c400197338ec509f4a45e4579">ap_set_content_type</a><code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/html</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
243 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#ga5e91eb6ca777c9a427b2e82bf1eeb81d">ap_rprintf</a><code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Hello, world!</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
245 <code style="color:#c34e00; ">/* Lastly, we must tell Apache that we took care of this request and everything went fine.</code>
246 <code style="color:#c34e00; "> * We do so by simply returning the value OK to Apache.</code>
247 <code style="color:#c34e00; "> */</code>
248 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
249 <code style="color:#806030; ">}</code>
254 Now, we put all we have learned together and end up with a program that looks like <a href="mod_example_1.c">
255 mod_example_1.c</a>. The functions used in this example will be explained later in the section
256 <a href="#functions">"Some useful functions you should know"</a>.
258 <h3><a name="request_rec" id="request_rec">The request_rec structure</a></h3>
259 <p>The most essential part of any request is the <em>request record</em>. In a call to a handler function, this
260 is represented by the <code>request_req*</code> structure passed along with every call that is made. This
261 struct, typically just refered to as <code>r</code> in modules, contains all the information you need for
262 your module to fully process any HTTP request and respond accordingly.</p>
263 <p>Some key elements of the <code>request_req</code> structure are:
265 <li><code><code style="color:#008833">r->handler</code> (char*)</code>: Contains the name of the handler Apache is currently asking to do the handling of this request</li>
266 <li><code><code style="color:#008833">r->method</code> (char*)</code>: Contains the HTTP method being used, f.x. GET or POST</li>
267 <li><code><code style="color:#008833">r->filename</code> (char*)</code>: Contains the translated filename the client is requesting</li>
268 <li><code><code style="color:#008833">r->args</code> (char*)</code>: Contains the query string of the request, if any</li>
269 <li><code><code style="color:#008833">r->headers_in</code> (apr_table_t*)</code>: Contains all the headers sent by the client</li>
270 <li><code><code style="color:#008833">r->connection</code> (conn_rec*)</code>: A record containing information about the current connection</li>
271 <li><code><code style="color:#008833">r->useragent_ip</code> (char*)</code>: The IP address of the client connecting to us</li>
272 <li><code><code style="color:#008833">r->pool</code> (apr_pool_t*)</code>: The memory pool of this request. We'll discuss this in the "
273 <a href="#memory">Memory management</a>" chapter.</li>
275 A complete list of all the values contained with in the <code>request_req</code> structure can be found in
276 the <a href="http://svn.apache.org/repos/asf/httpd/httpd/trunk/include/httpd.h"><code>httpd.h</code></a> header
277 file or at <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/structrequest__rec.html">http://ci.apache.org/projects/httpd/trunk/doxygen/structrequest__rec.html</a>.
280 Let's try out some of these variables in another example handler:<br />
284 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
285 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
286 <code style="color:#806030; ">{</code>
287 <code style="color:#c34e00; ">/* Set the appropriate content type */</code>
288 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#gaa2f8412c400197338ec509f4a45e4579">ap_set_content_type</a><code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/html</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
290 <code style="color:#c34e00; ">/* Print out the IP address of the client connecting to us: */</code>
291 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#ga5e91eb6ca777c9a427b2e82bf1eeb81d">ap_rprintf</a><code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; "><h2>Hello, </code><code style="color:#0f6900; ">%s</code><code style="color:#e60000; ">!</h2></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">useragent_ip</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
293 <code style="color:#c34e00; ">/* If we were reached through a GET or a POST request, be happy, else sad. */</code>
294 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code> <code style="color:#806030; ">!</code><code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">method</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">POST</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">|</code><code style="color:#806030; ">|</code> <code style="color:#806030; ">!</code><code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">method</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">GET</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
295 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">You used a GET or a POST method, that makes us happy!<br></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
296 <code style="color:#806030; ">}</code>
297 <code style="color:#400000; font-weight:bold; ">else</code> <code style="color:#806030; ">{</code>
298 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">You did not use POST or GET, that makes us sad :(<br></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
299 <code style="color:#806030; ">}</code>
301 <code style="color:#c34e00; ">/* Lastly, if there was a query string, let's print that too! */</code>
302 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">args</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
303 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#ga5e91eb6ca777c9a427b2e82bf1eeb81d">ap_rprintf</a><code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Your query string was: </code><code style="color:#0f6900; ">%s</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">args</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
304 <code style="color:#806030; ">}</code>
305 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
306 <code style="color:#806030; ">}</code>
314 <h3><a name="return_value" id="return_value">Return values</a></h3>
316 Apache relies on return values from handlers to signify whether a request was handled or not,
317 and if so, whether the request went well or not. If a module is not interested in handling
318 a specific request, it should always return the value <code>DECLINED</code>. If it is handling
319 a request, it should either return the generic value <code>OK</code>, or a specific HTTP status
324 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
325 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
326 <code style="color:#806030; ">{</code>
327 <code style="color:#c34e00; ">/* Return 404: Not found */</code>
328 <code style="color:#400000; font-weight:bold; ">return</code> HTTP_NOT_FOUND<code style="color:#806030; ">;</code>
329 <code style="color:#806030; ">}</code>
334 Returning <code>OK</code> or a HTTP status code does not necessarilly mean that the request will end. Apache
335 may still have other handlers that are interested in this request, for instance the logging modules
336 which, upon a successful request, will write down a summary of what was requested and how it went.
337 To do a full stop and prevent any further processing after your module is done, you can return the
338 value <code>DONE</code> to let Apache know that it should cease all activity on this request and
339 carry on with the next, without informing other handlers.
341 <strong>General response codes:</strong>
343 <li><code>DECLINED</code>: We are not handling this request</li>
344 <li><code>OK</code>: We handled this request and it went well</li>
345 <li><code>DONE</code>: We handled this request and Apache should just close this thread without further processing</li>
347 <strong>HTTP specific return codes (excerpt):</strong>
349 <li><code>HTTP_OK (200)</code>: Request was okay</li>
350 <li><code>HTTP_MOVED_PERMANENTLY (301)</code>: The resource has moved to a new URL</li>
351 <li><code>HTTP_UNAUTHORIZED (401)</code>: Client is not authorized to visit this page</li>
352 <li><code>HTTP_FORBIDDEN (403)</code>: Permission denied</li>
353 <li><code>HTTP_NOT_FOUND (404)</code>: File not found</li>
354 <li><code>HTTP_INTERNAL_SERVER_ERROR (500)</code>: Internal server error (self explanatory)</li>
359 <h3><a name="functions" id="functions">Some useful functions you should know</a></h3>
363 <code>ap_rputs(const char *string, request_req *r)</code>: <br />
364 Sends a string of text to the client. This is a shorthand version of <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#gac827cd0537d2b6213a7c06d7c26cc36e">
369 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">Hello, world!</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code></pre>
376 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#ga5e91eb6ca777c9a427b2e82bf1eeb81d">ap_rprintf</a></code>: <br />
377 This function works just like <code>printf</code>, except it sends the result to the client.
381 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;"><code style="color:#2e8800; "><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#ga5e91eb6ca777c9a427b2e82bf1eeb81d">ap_rprintf</a></code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Hello, </code><code style="color:#0f6900; ">%s</code><code style="color:#e60000; ">!</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">useragent_ip</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code></pre>
387 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#gaa2f8412c400197338ec509f4a45e4579">ap_set_content_type</a>(request_req *r, const char *type)</code>: <br />
388 Sets the content type of the output you are sending.
392 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;"><code style="color:#2e8800; "><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#gaa2f8412c400197338ec509f4a45e4579">ap_set_content_type</a></code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/plain</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* force a raw text output */</code></pre>
401 <h3><a name="memory" id="memory">Memory management</a></h3>
403 Managing your resources in Apache is quite easy, thanks to the memory pool system. In essence,
404 each server, connection and request have their own memory pool that gets cleaned up when its
405 scope ends, e.g. when a request is done or when a server process shuts down. All your module
406 needs to do is latch onto this memory pool, and you won't have to worry about having to clean
407 up after yourself - pretty neat, huh?</p>
410 In our module, we will primarilly be allocating memory for each request, so it's appropriate to
411 use the <code><code style="color:#008833">r->pool</code></code> reference when creating new objects. A few of the functions for
412 allocating memory within a pool are:
414 <li><code>void* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__pools.html#ga85f1e193c31d109affda72f9a92c6915">apr_palloc</a>(
415 apr_pool_t *p, apr_size_t size)</code>: Allocates <code>size</code> number of bytes in the pool for you</li>
416 <li><code>void* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__pools.html#gaf61c098ad258069d64cdf8c0a9369f9e">apr_pcalloc</a>(
417 apr_pool_t *p, apr_size_t size)</code>: Allocates <code>size</code> number of bytes in the pool for you and sets all bytes to 0</li>
418 <li><code>char* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__strings.html#gabc79e99ff19abbd7cfd18308c5f85d47">apr_pstrdup</a>(
419 apr_pool_t *p, const char *s)</code>: Creates a duplicate of the string <code>s</code>. This is useful for copying constant values so you can edit them</li>
420 <li><code>char* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__strings.html#ga3eca76b8d293c5c3f8021e45eda813d8">apr_psprintf</a>(
421 apr_pool_t *p, const char *fmt, ...)</code>: Similar to <code>sprintf</code>, except Apache supplies you with an appropriately allocated target variable</li>
424 Let's put these functions into an example handler:<br />
428 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
429 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
430 <code style="color:#806030; ">{</code>
431 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; ">*</code> original <code style="color:#806030; ">=</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">You can't edit this!</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
432 <code style="color:#c34e00; ">/* Allocate space for 10 integer values and set them all to zero. */</code>
433 <code style="color:#400000; font-weight:bold; ">int</code><code style="color:#806030; ">*</code> integers <code style="color:#806030; ">=</code> apr_pcalloc<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">pool</code><code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">sizeof</code><code style="color:#806030; ">(</code><code style="color:#400000; font-weight:bold; ">int</code><code style="color:#806030; ">)</code><code style="color:#806030; ">*</code><code style="color:#c00000; ">10</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
435 <code style="color:#c34e00; ">/* Create a copy of the 'original' variable that we can edit. */</code>
436 <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; ">*</code> copy <code style="color:#806030; ">=</code> apr_pstrdup<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">pool</code><code style="color:#806030; ">,</code> original<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
437 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
438 <code style="color:#806030; ">}</code>
442 This is all well and good for our module, which won't need any pre-initialized variables or structures.
443 However, if we wanted to initialize something early on, before the requests come rolling in, we could
444 simply add a call to a function in our <code>register_hooks</code> function to sort it out:
447 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
448 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">void</code> register_hooks<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">)</code>
449 <code style="color:#806030; ">{</code>
450 <code style="color:#c34e00; ">/* Call a function that initializes some stuff */</code>
451 <code style="color:#800040; ">example_init_function</code><code style="color:#806030; ">(</code>pool<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
452 <code style="color:#c34e00; ">/* Create a hook in the request handler, so we get called when a request arrives */</code>
453 <code style="color:#800040; ">ap_hook_handler</code><code style="color:#806030; ">(</code>example_handler<code style="color:#806030; ">,</code> <code style="color:#7f0055; font-weight:bold; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#7f0055; font-weight:bold; ">NULL</code><code style="color:#806030; ">,</code> APR_HOOK_LAST<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
454 <code style="color:#806030; ">}</code>
458 In this, pre-request initialization function, we would not be using the same pool as we did when
459 allocating resources for request-based functions. Instead, we would use the pool given to us by
460 Apache for allocating memory on a per-process based level.
465 <h3><a name="parsing" id="parsing">Parsing request data</a></h3>
467 In our example module, we would like to add a feature, that checks which type of digest, MD5 or SHA1
468 the client would like to see. This could be solved by adding a query string to the request. A query
469 string is typically comprised of several keys and values put together in a string, for instance
470 <code>valueA=yes&valueB=no&valueC=maybe</code>. It is up to the module itself to parse these
471 and get the data it requires. In our example, we'll be looking for a key called <code>digest</code>,
472 and if set to <code>md5</code>, we'll produce an MD5 digest, otherwise we'll produce a SHA1 digest.
475 Since the introduction of Apache 2.4, parsing request data from GET and POST requests have never
476 been easier. All we require to parse both GET and POST data is four simple lines:
480 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
481 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__apr__tables.html#gad7ea82d6608a4a633fc3775694ab71e4">apr_table_t</a> *GET;
482 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/structapr__array__header__t.html">apr_array_header_t</a> *POST;
484 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__SCRIPT.html#gaed25877b529623a4d8f99f819ba1b7bd">ap_args_to_table</a>(r, &GET);
485 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__DAEMON.html#ga9d426b6382b49754d4f87c55f65af202">ap_parse_form_data</a>(r, <code style="color:#7f0055; font-weight:bold; ">NULL</code>, &POST, -1, 8192);
490 In our specific example module, we're looking for the <code>digest</code> value from the query string,
491 which now resides inside a table called <code>GET</code>. To extract this value, we need only perform
492 a simple operation:<br />
496 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
497 <code style="color:#c34e00; ">/* Get the "digest" key from the query string, if any. */</code>
498 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>digestType <code style="color:#806030; ">=</code> <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__apr__tables.html#ga4db13e3915c6b9a3142b175d4c15d915">apr_table_get</a><code style="color:#806030; ">(</code>GET<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">digest</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
500 <code style="color:#c34e00; ">/* If no key was returned, we will set a default value instead. */</code>
501 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>digestType<code style="color:#806030; ">)</code> digestType <code style="color:#806030; ">=</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">sha1</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
507 The structures used for the POST and GET data are not exactly the same, so if we were to fetch a value from
508 POST data instead of the query string, we would have to resort to a few more lines, as outlined in
509 <a href="#get_post">this example</a> in the last chapter of this document.
513 <h3><a name="advanced_handler" id="advanced_handler">Making an advanced handler</a></h3>
514 Now that we have learned how to parse form data and manage our resources, we can move on to creating an advanced
515 version of our module, that spits out the MD5 or SHA1 digest of files:<br />
519 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
520 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
521 <code style="color:#806030; ">{</code>
522 <code style="color:#400000; font-weight:bold; ">int</code> rc<code style="color:#806030; ">,</code> exists<code style="color:#806030; ">;</code>
523 apr_finfo_t finfo<code style="color:#806030; ">;</code>
524 apr_file_t<code style="color:#806030; "> *</code>file<code style="color:#806030; ">;</code>
525 <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>filename<code style="color:#806030; ">;</code>
526 <code style="color:#400000; font-weight:bold; ">char</code> buffer<code style="color:#806030; ">[</code><code style="color:#c00000; ">256</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
527 apr_size_t readBytes<code style="color:#806030; ">;</code>
528 <code style="color:#400000; font-weight:bold; ">int</code> n<code style="color:#806030; ">;</code>
529 apr_table_t<code style="color:#806030; "> *</code>GET<code style="color:#806030; ">;</code>
530 apr_array_header_t<code style="color:#806030; "> *</code>POST<code style="color:#806030; ">;</code>
531 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>digestType<code style="color:#806030; ">;</code>
534 <code style="color:#c34e00; ">/* Check that the "example-handler" handler is being called. */</code>
535 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code> <code style="color:#806030; ">|</code><code style="color:#806030; ">|</code> <code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">example-handler</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#806030; ">(</code>DECLINED<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
537 <code style="color:#c34e00; ">/* Figure out which file is being requested by removing the .sum from it */</code>
538 filename <code style="color:#806030; ">=</code> apr_pstrdup<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">pool</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">filename</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
539 filename<code style="color:#806030; ">[</code><code style="color:#800040; ">strlen</code><code style="color:#806030; ">(</code>filename<code style="color:#806030; ">)</code><code style="color:#806030; ">-</code><code style="color:#c00000; ">4</code><code style="color:#806030; ">]</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Cut off the last 4 characters. */</code>
541 <code style="color:#c34e00; ">/* Figure out if the file we request a sum on exists and isn't a directory */</code>
542 rc <code style="color:#806030; ">=</code> apr_stat<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>finfo<code style="color:#806030; ">,</code> filename<code style="color:#806030; ">,</code> APR_FINFO_MIN<code style="color:#806030; ">,</code> r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">pool</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
543 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code>rc <code style="color:#806030; ">=</code><code style="color:#806030; ">=</code> APR_SUCCESS<code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
544 exists <code style="color:#806030; ">=</code>
545 <code style="color:#806030; ">(</code>
546 <code style="color:#806030; ">(</code>finfo<code style="color:#806030; ">.</code>filetype <code style="color:#806030; ">!</code><code style="color:#806030; ">=</code> APR_NOFILE<code style="color:#806030; ">)</code>
547 <code style="color:#806030; ">&</code><code style="color:#806030; ">&</code> <code style="color:#806030; ">!</code><code style="color:#806030; ">(</code>finfo<code style="color:#806030; ">.</code>filetype <code style="color:#806030; ">&</code> APR_DIR<code style="color:#806030; ">)</code>
548 <code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
549 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>exists<code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code> HTTP_NOT_FOUND<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Return a 404 if not found. */</code>
550 <code style="color:#806030; ">}</code>
551 <code style="color:#c34e00; ">/* If apr_stat failed, we're probably not allowed to check this file. */</code>
552 <code style="color:#400000; font-weight:bold; ">else</code> <code style="color:#400000; font-weight:bold; ">return</code> HTTP_FORBIDDEN<code style="color:#806030; ">;</code>
554 <code style="color:#c34e00; ">/* Parse the GET and, optionally, the POST data sent to us */</code>
556 ap_args_to_table<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>GET<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
557 ap_parse_form_data<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>POST<code style="color:#806030; ">,</code> <code style="color:#806030; ">-</code><code style="color:#c00000; ">1</code><code style="color:#806030; ">,</code> <code style="color:#c00000; ">8192</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
559 <code style="color:#c34e00; ">/* Set the appropriate content type */</code>
560 ap_set_content_type<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/html</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
562 <code style="color:#c34e00; ">/* Print a title and some general information */</code>
563 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; "><h2>Information on </code><code style="color:#0f6900; ">%s</code><code style="color:#e60000; ">:</h2></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> filename<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
564 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; "><b>Size:</b> </code><code style="color:#0f6900; ">%u</code><code style="color:#e60000; "> bytes<br/></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> finfo<code style="color:#806030; ">.</code>size<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
566 <code style="color:#c34e00; ">/* Get the digest type the client wants to see */</code>
567 digestType <code style="color:#806030; ">=</code> apr_table_get<code style="color:#806030; ">(</code>GET<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">digest</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
568 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>digestType<code style="color:#806030; ">)</code> digestType <code style="color:#806030; ">=</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">MD5</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
571 rc <code style="color:#806030; ">=</code> apr_file_open<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>file<code style="color:#806030; ">,</code> filename<code style="color:#806030; ">,</code> APR_READ<code style="color:#806030; ">,</code> APR_OS_DEFAULT<code style="color:#806030; ">,</code> r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">pool</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
572 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code>rc <code style="color:#806030; ">=</code><code style="color:#806030; ">=</code> APR_SUCCESS<code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
574 <code style="color:#c34e00; ">/* Are we trying to calculate the MD5 or the SHA1 digest? */</code>
575 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>digestType<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">md5</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
576 <code style="color:#c34e00; ">/* Calculate the MD5 sum of the file */</code>
577 <code style="color:#400000; font-weight:bold; ">union</code> <code style="color:#806030; ">{</code>
578 <code style="color:#400000; font-weight:bold; ">char</code> chr<code style="color:#806030; ">[</code><code style="color:#c00000; ">16</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
579 uint32_t num<code style="color:#806030; ">[</code><code style="color:#c00000; ">4</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
580 <code style="color:#806030; ">}</code> digest<code style="color:#806030; ">;</code>
581 apr_md5_ctx_t md5<code style="color:#806030; ">;</code>
582 apr_md5_init<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>md5<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
583 readBytes <code style="color:#806030; ">=</code> <code style="color:#c00000; ">256</code><code style="color:#806030; ">;</code>
584 <code style="color:#400000; font-weight:bold; ">while</code> <code style="color:#806030; ">(</code> apr_file_read<code style="color:#806030; ">(</code>file<code style="color:#806030; ">,</code> buffer<code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>readBytes<code style="color:#806030; ">)</code> <code style="color:#806030; ">=</code><code style="color:#806030; ">=</code> APR_SUCCESS <code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
585 apr_md5_update<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>md5<code style="color:#806030; ">,</code> buffer<code style="color:#806030; ">,</code> readBytes<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
586 <code style="color:#806030; ">}</code>
587 apr_md5_final<code style="color:#806030; ">(</code>digest<code style="color:#806030; ">.</code>chr<code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>md5<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
589 <code style="color:#c34e00; ">/* Print out the MD5 digest */</code>
590 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; "><b>MD5: </b><code></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
591 <code style="color:#400000; font-weight:bold; ">for</code> <code style="color:#806030; ">(</code>n <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code> n <code style="color:#806030; "><</code> APR_MD5_DIGESTSIZE<code style="color:#806030; ">/</code><code style="color:#c00000; ">4</code><code style="color:#806030; ">;</code> n<code style="color:#806030; ">+</code><code style="color:#806030; ">+</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
592 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#0f6900; ">%08x</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> digest<code style="color:#806030; ">.</code>num<code style="color:#806030; ">[</code>n<code style="color:#806030; ">]</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
593 <code style="color:#806030; ">}</code>
594 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; "></code></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
595 <code style="color:#c34e00; ">/* Print a link to the SHA1 version */</code>
596 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; "><br/><a href='?digest=sha1'>View the SHA1 hash instead</a></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
597 <code style="color:#806030; ">}</code>
598 <code style="color:#400000; font-weight:bold; ">else</code> <code style="color:#806030; ">{</code>
599 <code style="color:#c34e00; ">/* Calculate the SHA1 sum of the file */</code>
600 <code style="color:#400000; font-weight:bold; ">union</code> <code style="color:#806030; ">{</code>
601 <code style="color:#400000; font-weight:bold; ">char</code> chr<code style="color:#806030; ">[</code><code style="color:#c00000; ">20</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
602 uint32_t num<code style="color:#806030; ">[</code><code style="color:#c00000; ">5</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
603 <code style="color:#806030; ">}</code> digest<code style="color:#806030; ">;</code>
604 apr_sha1_ctx_t sha1<code style="color:#806030; ">;</code>
605 apr_sha1_init<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>sha1<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
606 readBytes <code style="color:#806030; ">=</code> <code style="color:#c00000; ">256</code><code style="color:#806030; ">;</code>
607 <code style="color:#400000; font-weight:bold; ">while</code> <code style="color:#806030; ">(</code> apr_file_read<code style="color:#806030; ">(</code>file<code style="color:#806030; ">,</code> buffer<code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>readBytes<code style="color:#806030; ">)</code> <code style="color:#806030; ">=</code><code style="color:#806030; ">=</code> APR_SUCCESS <code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
608 apr_sha1_update<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>sha1<code style="color:#806030; ">,</code> buffer<code style="color:#806030; ">,</code> readBytes<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
609 <code style="color:#806030; ">}</code>
610 apr_sha1_final<code style="color:#806030; ">(</code>digest<code style="color:#806030; ">.</code>chr<code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>sha1<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
612 <code style="color:#c34e00; ">/* Print out the SHA1 digest */</code>
613 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; "><b>SHA1: </b><code></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
614 <code style="color:#400000; font-weight:bold; ">for</code> <code style="color:#806030; ">(</code>n <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code> n <code style="color:#806030; "><</code> APR_SHA1_DIGESTSIZE<code style="color:#806030; ">/</code><code style="color:#c00000; ">4</code><code style="color:#806030; ">;</code> n<code style="color:#806030; ">+</code><code style="color:#806030; ">+</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
615 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#0f6900; ">%08x</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> digest<code style="color:#806030; ">.</code>num<code style="color:#806030; ">[</code>n<code style="color:#806030; ">]</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
616 <code style="color:#806030; ">}</code>
617 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; "></code></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
619 <code style="color:#c34e00; ">/* Print a link to the MD5 version */</code>
620 ap_rputs<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; "><br/><a href='?digest=md5'>View the MD5 hash instead</a></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
621 <code style="color:#806030; ">}</code>
622 apr_file_close<code style="color:#806030; ">(</code>file<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
624 <code style="color:#806030; ">}</code>
628 <code style="color:#c34e00; ">/* Let Apache know that we responded to this request. */</code>
629 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
630 <code style="color:#806030; ">}</code>
635 This version in its entirity can be found here: <a href="mod_example_2.c">mod_example_2.c</a>.
638 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
639 <div class="section">
640 <h2><a name="configuration" id="configuration">Adding configuration options</a></h2>
642 In this next segment of this document, we will turn our eyes away from the digest module and create a new
643 example module, whose only function is to write out its own configuration. The purpose of this is to
644 examine how Apache works with configuration, and what happens when you start writing advanced configurations
647 <h3><a name="config_intro" id="config_intro">An introduction to configuration directives</a></h3>
648 If you are reading this, then you probably already know what a configuration directive is. Simply put,
649 a directive is a way of telling an individual module (or a set of modules) how to behave, such as these
650 directives control how <code>mod_rewrite</code> works:
651 <div class="example"><pre>
653 RewriteCond %{REQUEST_URI} ^/foo/bar
654 RewriteRule ^/foo/bar/(.*)$ /foobar?page=$1
656 Each of these configuration directives are handled by a separate function, that parses the parameters given
657 and sets up a configuration accordingly.
659 <h3><a name="config_simple" id="config_simple">Making an example configuration</a></h3>
660 To begin with, we'll create a basic configuration in C-space:
664 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
665 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
666 <code style="color:#400000; font-weight:bold; ">int</code> enabled<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Enable or disable our module */</code>
667 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>path<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Some path to...something */</code>
668 <code style="color:#400000; font-weight:bold; ">int</code> typeOfAction<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* 1 means action A, 2 means action B and so on */</code>
669 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
674 Now, let's put this into perspective by creating a very small module that just prints out a hard-coded
675 configuration. You'll notice that we use the <code>register_hooks</code> function for initializing the
676 configuration values to their defaults:
680 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
681 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
682 <code style="color:#400000; font-weight:bold; ">int</code> enabled<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Enable or disable our module */</code>
683 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>path<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Some path to...something */</code>
684 <code style="color:#400000; font-weight:bold; ">int</code> typeOfAction<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* 1 means action A, 2 means action B and so on */</code>
685 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
687 <code style="color:#400000; font-weight:bold; ">static</code> example_config config<code style="color:#806030; ">;</code>
689 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
690 <code style="color:#806030; ">{</code>
691 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code> <code style="color:#806030; ">|</code><code style="color:#806030; ">|</code> <code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">example-handler</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code><code style="color:#806030; ">(</code>DECLINED<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
692 ap_set_content_type<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/plain</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
693 ap_rprintf<code style="color:#806030; ">(r, </code><code style="color:#800000; ">"</code><code style="color:#e60000; ">Enabled: </code><code style="color:#0f6900; ">%u</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">.</code>enabled<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
694 ap_rprintf<code style="color:#806030; ">(r, </code><code style="color:#800000; ">"</code><code style="color:#e60000; ">Path: </code><code style="color:#0f6900; ">%s</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">.</code>path<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
695 ap_rprintf<code style="color:#806030; ">(r, </code><code style="color:#800000; ">"</code><code style="color:#e60000; ">TypeOfAction: </code><code style="color:#0f6900; ">%x</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">.</code>typeOfAction<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
696 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
697 <code style="color:#806030; ">}</code>
699 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">void</code> register_hooks<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">)</code>
700 <code style="color:#806030; ">{</code>
701 config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">;</code>
702 config<code style="color:#806030; ">.</code>path <code style="color:#806030; ">=</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">/foo/bar</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
703 config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x00</code><code style="color:#806030; ">;</code>
704 ap_hook_handler<code style="color:#806030; ">(</code>example_handler<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> APR_HOOK_LAST<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
705 <code style="color:#806030; ">}</code>
707 <code style="color:#c34e00; ">/* Define our module as an entity and assign a function for registering hooks */</code>
709 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
710 <code style="color:#806030; ">{</code>
711 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
712 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
713 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
714 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
715 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
716 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
717 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
718 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
723 So far so good. To access our new handler, we could add the following to our configuration:
724 <div class="example"><pre>
725 <Location /example>
726 SetHandler example-handler
729 When we visit, we'll see our current configuration being spit out by our module.
732 <h3><a name="register_directive" id="register_directive">Registering directives with Apache</a></h3>
733 What if we want to change our configuration, not by hard-coding new values into the module,
734 but by using either the httpd.conf file or possibly a .htaccess file? It's time to let Apache
735 know that we want this to be possible. To do so, we must first change our <em>name tag</em>
736 to include a reference to the configuration directives we want to register with Apache:
740 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
741 module AP_MODULE_DECLARE_DATA example_module =
743 STANDARD20_MODULE_STUFF,
744 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
745 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
746 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
747 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
748 example_directives, <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
749 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
755 This will tell Apache that we are now accepting directives from the configuration files, and that the
756 structure called <code>example_directives</code> holds information on what our directives are and how
757 they work. Since we have three different variables in our module configuration, we will add a structure
758 with three directives and a NULL at the end:
762 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
763 static const command_rec example_directives[] =
765 <code style="color:#2e8800; "><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a></code>("exampleEnabled", example_set_enabled, <code style="color:#7f0055; font-weight:bold; ">NULL</code>, RSRC_CONF, "Enable or disable mod_example"),
766 <code style="color:#2e8800; "><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a></code>("examplePath", example_set_path, <code style="color:#7f0055; font-weight:bold; ">NULL</code>, RSRC_CONF, "The path to whatever"),
767 <code style="color:#2e8800; "><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#gafaec43534fcf200f37d9fecbf9247c21">AP_INIT_TAKE2</a></code>("exampleAction", example_set_action, <code style="color:#7f0055; font-weight:bold; ">NULL</code>, RSRC_CONF, "Special action value!"),
768 { <code style="color:#7f0055; font-weight:bold; ">NULL</code> }
774 <img src="../images/build_a_mod_4.png" border="1" /><br />
776 As you can see, each directive needs at least 5 parameters set:
778 <li><code><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a></code>: This is a macro that tells Apache that this directive takes one and only one argument.
779 If we required two arguments, we could use the macro <code><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#gafaec43534fcf200f37d9fecbf9247c21">AP_INIT_TAKE2</a></code> and so on (refer to httpd_conf.h
780 for more macros).</li>
781 <li><code>exampleEnabled</code>: This is the name of our directive. More precisely, it is what the user must put in his/her
782 configuration in order to invoke a configuration change in our module.</li>
783 <li><code>example_set_enabled</code>: This is a reference to a C function that parses the directive and sets the configuration
784 accordingly. We will discuss how to make this in the following paragraph.</li>
785 <li><code>RSRC_CONF</code>: This tells Apache where the directive is permissable. We'll go into details on this value in the
786 later chapters, but for now, <code>RSRC_CONF</code> means that Apache will only accept these directives in a server context.</li>
787 <li><code>"Enable or disable...."</code>: This is simply a brief description of what the directive does.</li>
789 (<em>The "missing" parameter in our definition, which is usually set to <code>NULL</code>, is an optional function that can be
790 run after the initial function to parse the arguments have been run. This is usually omitted, as the function for verifying
791 arguments might as well be used to set them.</em>)
794 <h3><a name="directive_handler" id="directive_handler">The directive handler function</a></h3>
796 Now that we've told Apache to expect some directives for our module, it's time to make a few functions for handling these. What
797 Apache reads in the configuration file(s) is text, and so naturally, what it passes along to our directive handler is one or
798 more strings, that we ourselves need to recognize and act upon. You'll notice, that since we set our <code>exampleAction</code>
799 directive to accept two arguments, its C function also has an additional parameter defined:<br />
803 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
804 <code style="color:#c34e00; ">/* Handler for the "exambleEnabled" directive */</code>
805 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>example_set_enabled<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code>
806 <code style="color:#806030; ">{</code>
807 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">on</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">;</code>
808 <code style="color:#400000; font-weight:bold; ">else</code> config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
809 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
810 <code style="color:#806030; ">}</code>
812 <code style="color:#c34e00; ">/* Handler for the "examplePath" directive */</code>
813 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>example_set_path<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code>
814 <code style="color:#806030; ">{</code>
815 config<code style="color:#806030; ">.</code>path <code style="color:#806030; ">=</code> arg<code style="color:#806030; ">;</code>
816 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
817 <code style="color:#806030; ">}</code>
819 <code style="color:#c34e00; ">/* Handler for the "exampleAction" directive */</code>
820 <code style="color:#c34e00; ">/* Let's pretend this one takes one argument (file or db), and a second (deny or allow), */</code>
821 <code style="color:#c34e00; ">/* and we store it in a bit-wise manner. */</code>
822 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>example_set_action<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg1<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; ">*</code> arg2<code style="color:#806030; ">)</code>
823 <code style="color:#806030; ">{</code>
824 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg1<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">file</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x01</code><code style="color:#806030; ">;</code>
825 <code style="color:#400000; font-weight:bold; ">else</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x02</code><code style="color:#806030; ">;</code>
827 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg2<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">deny</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x10</code><code style="color:#806030; ">;</code>
828 <code style="color:#400000; font-weight:bold; ">else</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x20</code><code style="color:#806030; ">;</code>
829 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
830 <code style="color:#806030; ">}</code>
837 <h3><a name="directive_complete" id="directive_complete">Putting it all together</a></h3>
839 Now that we have our directives set up, and handlers configured for them, we can assemble our module
844 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
845 <code style="color:#c34e00; ">/* mod_example_config_simple.c: */</code>
846 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; "><</code><code style="color:#40015a; ">stdio.h</code><code style="color:#800000; ">></code>
847 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">apr_hash.h</code><code style="color:#800000; ">"</code>
848 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">ap_config.h</code><code style="color:#800000; ">"</code>
849 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">ap_provider.h</code><code style="color:#800000; ">"</code>
850 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">httpd.h</code><code style="color:#800000; ">"</code>
851 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_core.h</code><code style="color:#800000; ">"</code>
852 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_config.h</code><code style="color:#800000; ">"</code>
853 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_log.h</code><code style="color:#800000; ">"</code>
854 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_protocol.h</code><code style="color:#800000; ">"</code>
855 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_request.h</code><code style="color:#800000; ">"</code>
857 <code style="color:#c34e00; ">/*</code>
858 <code style="color:#c34e00; "> ==============================================================================</code>
859 <code style="color:#c34e00; "> Our configuration prototype and declaration:</code>
860 <code style="color:#c34e00; "> ==============================================================================</code>
861 <code style="color:#c34e00; "> */</code>
862 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
863 <code style="color:#400000; font-weight:bold; ">int</code> enabled<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Enable or disable our module */</code>
864 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>path<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* Some path to...something */</code>
865 <code style="color:#400000; font-weight:bold; ">int</code> typeOfAction<code style="color:#806030; ">;</code> <code style="color:#c34e00; ">/* 1 means action A, 2 means action B and so on */</code>
866 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
868 <code style="color:#400000; font-weight:bold; ">static</code> example_config config<code style="color:#806030; ">;</code>
870 <code style="color:#c34e00; ">/*</code>
871 <code style="color:#c34e00; "> ==============================================================================</code>
872 <code style="color:#c34e00; "> Our directive handlers:</code>
873 <code style="color:#c34e00; "> ==============================================================================</code>
874 <code style="color:#c34e00; "> */</code>
875 <code style="color:#c34e00; ">/* Handler for the "exambleEnabled" directive */</code>
876 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>example_set_enabled<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code>
877 <code style="color:#806030; ">{</code>
878 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">on</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">;</code>
879 <code style="color:#400000; font-weight:bold; ">else</code> config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
880 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
881 <code style="color:#806030; ">}</code>
883 <code style="color:#c34e00; ">/* Handler for the "examplePath" directive */</code>
884 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>example_set_path<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code>
885 <code style="color:#806030; ">{</code>
886 config<code style="color:#806030; ">.</code>path <code style="color:#806030; ">=</code> arg<code style="color:#806030; ">;</code>
887 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
888 <code style="color:#806030; ">}</code>
890 <code style="color:#c34e00; ">/* Handler for the "exampleAction" directive */</code>
891 <code style="color:#c34e00; ">/* Let's pretend this one takes one argument (file or db), and a second (deny or allow), */</code>
892 <code style="color:#c34e00; ">/* and we store it in a bit-wise manner. */</code>
893 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; "> *</code>example_set_action<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg1<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; ">*</code> arg2<code style="color:#806030; ">)</code>
894 <code style="color:#806030; ">{</code>
895 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg1<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">file</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x01</code><code style="color:#806030; ">;</code>
896 <code style="color:#400000; font-weight:bold; ">else</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x02</code><code style="color:#806030; ">;</code>
898 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg2<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">deny</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x10</code><code style="color:#806030; ">;</code>
899 <code style="color:#400000; font-weight:bold; ">else</code> config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x20</code><code style="color:#806030; ">;</code>
900 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
901 <code style="color:#806030; ">}</code>
903 <code style="color:#c34e00; ">/*</code>
904 <code style="color:#c34e00; "> ==============================================================================</code>
905 <code style="color:#c34e00; "> The directive structure for our name tag:</code>
906 <code style="color:#c34e00; "> ==============================================================================</code>
907 <code style="color:#c34e00; "> */</code>
908 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">const</code> command_rec example_directives<code style="color:#806030; ">[</code><code style="color:#806030; ">]</code> <code style="color:#806030; ">=</code>
909 <code style="color:#806030; ">{</code>
910 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a><code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">exampleEnabled</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> example_set_enabled<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> RSRC_CONF<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Enable or disable mod_example</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">,</code>
911 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a><code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">examplePath</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> example_set_path<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> RSRC_CONF<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">The path to whatever</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">,</code>
912 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#gafaec43534fcf200f37d9fecbf9247c21">AP_INIT_TAKE2</a><code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">exampleAction</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> example_set_action<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> RSRC_CONF<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Special action value!</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">,</code>
913 <code style="color:#806030; ">{</code> <code style="color:#007d45; ">NULL</code> <code style="color:#806030; ">}</code>
914 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
915 <code style="color:#c34e00; ">/*</code>
916 <code style="color:#c34e00; "> ==============================================================================</code>
917 <code style="color:#c34e00; "> Our module handler:</code>
918 <code style="color:#c34e00; "> ==============================================================================</code>
919 <code style="color:#c34e00; "> */</code>
920 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
921 <code style="color:#806030; ">{</code>
922 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code> <code style="color:#806030; ">|</code><code style="color:#806030; ">|</code> <code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">example-handler</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code><code style="color:#806030; ">(</code>DECLINED<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
923 ap_set_content_type<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/plain</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
924 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Enabled: </code><code style="color:#0f6900; ">%u</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">.</code>enabled<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
925 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Path: </code><code style="color:#0f6900; ">%s</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">.</code>path<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
926 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">TypeOfAction: </code><code style="color:#0f6900; ">%x</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">.</code>typeOfAction<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
927 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
928 <code style="color:#806030; ">}</code>
930 <code style="color:#c34e00; ">/*</code>
931 <code style="color:#c34e00; "> ==============================================================================</code>
932 <code style="color:#c34e00; "> The hook registration function (also initializes the default config values):</code>
933 <code style="color:#c34e00; "> ==============================================================================</code>
934 <code style="color:#c34e00; "> */</code>
935 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">void</code> register_hooks<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">)</code>
936 <code style="color:#806030; ">{</code>
937 config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">;</code>
938 config<code style="color:#806030; ">.</code>path <code style="color:#806030; ">=</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">/foo/bar</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
939 config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">3</code><code style="color:#806030; ">;</code>
940 ap_hook_handler<code style="color:#806030; ">(</code>example_handler<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> APR_HOOK_LAST<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
941 <code style="color:#806030; ">}</code>
942 <code style="color:#c34e00; ">/*</code>
943 <code style="color:#c34e00; "> ==============================================================================</code>
944 <code style="color:#c34e00; "> Our module name tag:</code>
945 <code style="color:#c34e00; "> ==============================================================================</code>
946 <code style="color:#c34e00; "> */</code>
947 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
948 <code style="color:#806030; ">{</code>
949 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
950 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
951 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
952 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
953 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
954 example_directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
955 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
956 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
963 In our httpd.conf file, we can now change the hard-coded configuration by adding a few lines:
964 <div class="example"><pre>
966 ExamplePath "/usr/bin/foo"
967 ExampleAction file allow
969 And thus we apply the configuration, visit <code>/example</code> on our web site, and we see the configuration has
970 adapted to what we wrote in our configuration file.
975 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
976 <div class="section">
977 <h2><a name="context" id="context">Context aware configurations</a></h2>
978 <h3><a name="context_intro" id="context_intro">Introduction to context aware configurations</a></h3>
980 In Apache, different URLs, virtual hosts, directories etc can have very different meanings
981 to the user of Apache, and thus different contexts within which modules must operate. For example,
982 let's assume you have this configuration set up for mod_rewrite:
983 <div class="example"><pre>
984 <Directory "/var/www">
985 RewriteCond %{HTTP_HOST} ^example.com$
986 RewriteRule (.*) http://www.example.com/$1
988 <Directory "/var/www/sub">
989 RewriteRule ^foobar$ index.php?foobar=true
992 In this example, you will have set up two different contexts for mod_rewrite:
994 <li>Inside <code>/var/www</code>, all requests for <code>http://example.com</code> must go to <code>http://www.example.com</code></li>
995 <li>Inside <code>/var/www/sub</code>, all requests for <code>foobar</code> must go to <code>index.php?foobar=true</code></li>
997 If mod_rewrite (or Apache for that matter) wasn't context aware, then these rewrite rules would just apply to every and any request made,
998 regardless of where and how they were made, but since the module can pull the context specific configuration straight from Apache, it
999 does not need to know itself, which of the directives are valid in this context, since Apache takes care of this.</p>
1002 So how does a module get the specific configuration for the server, directory or location in question? It does so by making one simple call:
1006 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1010 example_config *config = (example_config*) <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga1093a5908a384eacc929b028c79f2a02">ap_get_module_config</a>(<code style="color:#008833">r->per_dir_config</code>, &example_module);
1012 That's it! Of course, a whole lot goes on behind the scenes, which we will discuss in this chapter, starting with how
1013 Apache came to know what our configuration looks like, and how it came to be set up as it is in the specific context.
1017 <h3><a name="context_base" id="context_base">Our basic configuration setup</a></h3>
1018 <p>In this chapter, we will be working with a slightly modified version of our previous
1019 context structure. We will set a <code>context</code> variable that we can use to track
1020 which context configuration is being used by Apache in various places:
1024 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1025 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
1026 <code style="color:#400000; font-weight:bold; ">char</code> context<code style="color:#806030; ">[</code><code style="color:#c00000; ">256</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
1027 <code style="color:#400000; font-weight:bold; ">char</code> path<code style="color:#806030; ">[</code><code style="color:#c00000; ">256</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
1028 <code style="color:#400000; font-weight:bold; ">int</code> typeOfAction<code style="color:#806030; ">;</code>
1029 <code style="color:#400000; font-weight:bold; ">int</code> enabled<code style="color:#806030; ">;</code>
1030 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
1037 <p>Our handler for requests will also be modified, yet still very simple:
1041 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1042 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
1043 <code style="color:#806030; ">{</code>
1044 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code> <code style="color:#806030; ">|</code><code style="color:#806030; ">|</code> <code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">example-handler</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code><code style="color:#806030; ">(</code>DECLINED<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1045 example_config<code style="color:#806030; "> *</code>config <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config<code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> ap_get_module_config<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">per_dir_config</code><code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>example_module<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1046 ap_set_content_type<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/plain</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1047 ap_rprintf<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">Enabled: </code><code style="color:#0f6900; ">%u</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1048 ap_rprintf<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">Path: </code><code style="color:#0f6900; ">%s</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1049 ap_rprintf<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">TypeOfAction: </code><code style="color:#0f6900; ">%x</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1050 ap_rprintf<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">Context: </code><code style="color:#0f6900; ">%s</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">context</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1051 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1052 <code style="color:#806030; ">}</code>
1061 <h3><a name="context_which" id="context_which">Choosing a context</a></h3>
1063 Before we can start making our module context aware, we must first define, which contexts we will accept.
1064 As we saw in the previous chapter, defining a directive required five elements be set:
1068 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1069 <code style="color:#2e8800; "><a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a></code>("exampleEnabled", example_set_enabled, <code style="color:#7f0055; font-weight:bold; ">NULL</code>, RSRC_CONF, "Enable or disable mod_example"),
1074 The <code>RSRC_CONF</code> definition told Apache that we would only allow this directive in a global server context, but
1075 since we are now trying out a context aware version of our module, we should set this to something more lenient, namely
1076 the value <code>ACCESS_CONF</code>, which lets us use the directive inside <Directory> and <Location> blocks.
1080 <h3><a name="context_pool" id="context_pool">Using Apache to allocate configuration slots</a></h3>
1081 <p> A much smarter way to manage your configurations is by letting Apache help you create them.
1082 To do so, we must first start off by chancing our <em>name tag</em> to let Apache know, that
1083 it should assist us in creating and managing our configurations. Since we have chosen the per-directory
1084 (or per-location) context for our module configurations, we'll add a per-directory creator and merger
1085 function reference in our tag:
1088 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1089 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
1090 <code style="color:#806030; ">{</code>
1091 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
1092 create_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
1093 merge_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
1094 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
1095 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
1096 directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
1097 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
1098 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
1109 <h3><a name="context_which" id="context_which">Creating new context configurations</a></h3>
1111 Now that we have told Apache to help us create and manage configurations, our first step is to
1112 make a function for creating new, blank configurations. We do so by creating the function we just
1113 referenced in our name tag as the Per-directory configuration handler:
1115 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1116 <code style="color:#400000; font-weight:bold; ">void</code><code style="color:#806030; ">*</code> example_create_dir_conf<code style="color:#806030; ">(</code>apr_pool_t<code style="color:#806030; ">*</code> pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; ">*</code> context<code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1117 context <code style="color:#806030; ">=</code> context <code style="color:#806030; ">?</code> context <code style="color:#806030; ">:</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">(undefined context)</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
1118 example_config<code style="color:#806030; "> *</code>cfg <code style="color:#806030; ">=</code> apr_pcalloc<code style="color:#806030; ">(</code>pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">sizeof</code><code style="color:#806030; ">(</code>example_config<code style="color:#806030; ">)</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1119 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>cfg<code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1120 <code style="color:#c34e00; ">/* Set some default values */</code>
1121 <code style="color:#800040; ">strcpy</code><code style="color:#806030; ">(</code>cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">context</code><code style="color:#806030; ">,</code> x<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1122 cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1123 cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code> <code style="color:#806030; ">=</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">/foo/bar</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
1124 cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x11</code><code style="color:#806030; ">;</code>
1125 <code style="color:#806030; ">}</code>
1126 <code style="color:#400000; font-weight:bold; ">return</code> dir<code style="color:#806030; ">;</code>
1127 <code style="color:#806030; ">}</code>
1135 <h3><a name="context_which" id="context_which">Merging configurations</a></h3>
1137 Our next step in creating a context aware configuration is merging configurations. This part of the process
1138 particularly apply to scenarios where you have a parent configuration and a child, such as the following:
1139 <div class="example"><pre>
1140 <Directory "/var/www">
1142 ExamplePath /foo/bar
1143 ExampleAction file allow
1145 <Directory "/var/www/subdir">
1146 ExampleAction file deny
1149 In this example, it is natural to assume that the directory <code>/var/www/subdir</code> should inherit the
1150 value set for the <code>/var/www</code> directory, as we did not specify a <code>ExampleEnable</code> nor an
1151 <code>ExamplePath</code> for this directory. Apache does not presume to know if this is true, but cleverly
1154 <li>Creates a new configuration for <code>/var/www</code></li>
1155 <li>Sets the configuration values according to the directives given for <code>/var/www</code></li>
1156 <li>Creates a new configuration for <code>/var/www/subdir</code></li>
1157 <li>Sets the configuration values according to the directives given for <code>/var/www/subdir</code></li>
1158 <li><strong>Proposes a merge</strong> of the two configurations into a new configuration for <code>/var/www/subdir</code></li>
1160 This proposal is handled by the <code>merge_dir_conf</code> function we referenced in our name tag. The purpose of
1161 this function is to assess the two configurations and decide how they are to be merged:
1165 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1166 <code style="color:#400000; font-weight:bold; ">void</code><code style="color:#806030; ">*</code> merge_dir_conf<code style="color:#806030; ">(</code>apr_pool_t<code style="color:#806030; ">*</code> pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code><code style="color:#806030; ">*</code> BASE<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code><code style="color:#806030; ">*</code> ADD<code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1167 example_config<code style="color:#806030; ">*</code> base <code style="color:#806030; ">=</code> BASE <code style="color:#806030; ">;</code>
1168 example_config<code style="color:#806030; ">*</code> add <code style="color:#806030; ">=</code> ADD <code style="color:#806030; ">;</code>
1169 example_config<code style="color:#806030; ">*</code> conf <code style="color:#806030; ">=</code> create_dir_conf<code style="color:#806030; ">(</code>pool<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Merged configuration</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1171 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code> <code style="color:#806030; ">)</code> <code style="color:#806030; ">?</code> base<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">:</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">;</code>
1172 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">=</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">?</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">:</code> base<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code><code style="color:#806030; ">;</code>
1173 <code style="color:#800040; ">strcpy</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">,</code> <code style="color:#800040; ">strlen</code><code style="color:#806030; ">(</code>add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">?</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code> <code style="color:#806030; ">:</code> base<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1175 <code style="color:#400000; font-weight:bold; ">return</code> conf <code style="color:#806030; ">;</code>
1176 <code style="color:#806030; ">}</code>
1183 <h3><a name="context_which" id="context_which">Trying out our new context aware configurations</a></h3>
1185 Now, let's try putting it all together to create a new module that it context aware. First off, we'll
1186 create a configuration that lets us test how the module works:
1187 <div class="example"><pre>
1188 <Location "/a">
1189 SetHandler example-handler
1191 ExamplePath "/foo/bar"
1192 ExampleAction file allow
1195 <Location "/a/b">
1196 ExampleAction file deny
1200 <Location "/a/b/c">
1201 ExampleAction db deny
1202 ExamplePath "/foo/bar/baz"
1206 Then we'll assemble our module code. Note, that since we are now using our name tag as reference when fetching
1207 configurations in our handler, I have added some prototypes to keep the compiler happy:
1211 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1212 <code style="color:#c34e00; ">/*$6</code>
1213 <code style="color:#c34e00; "> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</code>
1214 <code style="color:#c34e00; "> * mod_example_config.c</code>
1215 <code style="color:#c34e00; "> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</code>
1216 <code style="color:#c34e00; "> */</code>
1219 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; "><</code><code style="color:#40015a; ">stdio.h</code><code style="color:#800000; ">></code>
1220 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">apr_hash.h</code><code style="color:#800000; ">"</code>
1221 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">ap_config.h</code><code style="color:#800000; ">"</code>
1222 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">ap_provider.h</code><code style="color:#800000; ">"</code>
1223 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">httpd.h</code><code style="color:#800000; ">"</code>
1224 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_core.h</code><code style="color:#800000; ">"</code>
1225 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_config.h</code><code style="color:#800000; ">"</code>
1226 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_log.h</code><code style="color:#800000; ">"</code>
1227 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_protocol.h</code><code style="color:#800000; ">"</code>
1228 <code style="color:#004a43; ">#</code><code style="color:#004a43; ">include </code><code style="color:#800000; ">"</code><code style="color:#40015a; ">http_request.h</code><code style="color:#800000; ">"</code>
1230 <code style="color:#c34e00; ">/*$1</code>
1231 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1232 <code style="color:#c34e00; "> Configuration structure</code>
1233 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1234 <code style="color:#c34e00; "> */</code>
1236 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code>
1237 <code style="color:#806030; ">{</code>
1238 <code style="color:#400000; font-weight:bold; ">char</code> context<code style="color:#806030; ">[</code><code style="color:#c00000; ">256</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
1239 <code style="color:#400000; font-weight:bold; ">char</code> path<code style="color:#806030; ">[</code><code style="color:#c00000; ">256</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
1240 <code style="color:#400000; font-weight:bold; ">int</code> typeOfAction<code style="color:#806030; ">;</code>
1241 <code style="color:#400000; font-weight:bold; ">int</code> enabled<code style="color:#806030; ">;</code>
1242 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
1244 <code style="color:#c34e00; ">/*$1</code>
1245 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1246 <code style="color:#c34e00; "> Prototypes</code>
1247 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1248 <code style="color:#c34e00; "> */</code>
1250 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1251 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>example_set_enabled<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1252 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>example_set_path<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1253 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>example_set_action<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg1<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg2<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1254 <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>create_dir_conf<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>context<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1255 <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>merge_dir_conf<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>BASE<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>ADD<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1256 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">void</code> register_hooks<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1258 <code style="color:#c34e00; ">/*$1</code>
1259 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1260 <code style="color:#c34e00; "> Configuration directives</code>
1261 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1262 <code style="color:#c34e00; "> */</code>
1264 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">const</code> command_rec directives<code style="color:#806030; ">[</code><code style="color:#806030; ">]</code> <code style="color:#806030; ">=</code>
1265 <code style="color:#806030; ">{</code>
1266 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a><code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">exampleEnabled</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> example_set_enabled<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> ACCESS_CONF<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Enable or disable mod_example</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">,</code>
1267 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#ga07c7d22ae17805e61204463326cf9c34">AP_INIT_TAKE1</a><code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">examplePath</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> example_set_path<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> ACCESS_CONF<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">The path to whatever</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">,</code>
1268 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__CONFIG.html#gafaec43534fcf200f37d9fecbf9247c21">AP_INIT_TAKE2</a><code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">exampleAction</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> example_set_action<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> ACCESS_CONF<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Special action value!</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">,</code>
1269 <code style="color:#806030; ">{</code> <code style="color:#007d45; ">NULL</code> <code style="color:#806030; ">}</code>
1270 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
1272 <code style="color:#c34e00; ">/*$1</code>
1273 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1274 <code style="color:#c34e00; "> Our name tag</code>
1275 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1276 <code style="color:#c34e00; "> */</code>
1278 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
1279 <code style="color:#806030; ">{</code>
1280 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
1281 create_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
1282 merge_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
1283 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
1284 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
1285 directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
1286 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
1287 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
1289 <code style="color:#c34e00; ">/*</code>
1290 <code style="color:#c34e00; "> =======================================================================================================================</code>
1291 <code style="color:#c34e00; "> Hook registration function</code>
1292 <code style="color:#c34e00; "> =======================================================================================================================</code>
1293 <code style="color:#c34e00; "> */</code>
1294 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">void</code> register_hooks<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">)</code>
1295 <code style="color:#806030; ">{</code>
1296 ap_hook_handler<code style="color:#806030; ">(</code>example_handler<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> APR_HOOK_LAST<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1297 <code style="color:#806030; ">}</code>
1299 <code style="color:#c34e00; ">/*</code>
1300 <code style="color:#c34e00; "> =======================================================================================================================</code>
1301 <code style="color:#c34e00; "> Our example web service handler</code>
1302 <code style="color:#c34e00; "> =======================================================================================================================</code>
1303 <code style="color:#c34e00; "> */</code>
1304 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
1305 <code style="color:#806030; ">{</code>
1306 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code> <code style="color:#806030; ">|</code><code style="color:#806030; ">|</code> <code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">handler</code><code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">example-handler</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code><code style="color:#806030; ">(</code>DECLINED<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1308 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1309 example_config <code style="color:#806030; ">*</code>config <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> ap_get_module_config<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">per_dir_config</code><code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>example_module<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1310 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1312 ap_set_content_type<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">text/plain</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1313 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Enabled: </code><code style="color:#0f6900; ">%u</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1314 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Path: </code><code style="color:#0f6900; ">%s</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1315 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">TypeOfAction: </code><code style="color:#0f6900; ">%x</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1316 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Context: </code><code style="color:#0f6900; ">%s</code><code style="color:#0f6900; ">\n</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> config<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">context</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1317 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1318 <code style="color:#806030; ">}</code>
1320 <code style="color:#c34e00; ">/*</code>
1321 <code style="color:#c34e00; "> =======================================================================================================================</code>
1322 <code style="color:#c34e00; "> Handler for the "exambleEnabled" directive</code>
1323 <code style="color:#c34e00; "> =======================================================================================================================</code>
1324 <code style="color:#c34e00; "> */</code>
1325 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>example_set_enabled<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code>
1326 <code style="color:#806030; ">{</code>
1327 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1328 example_config <code style="color:#806030; ">*</code>conf <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> cfg<code style="color:#806030; ">;</code>
1329 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1331 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">)</code>
1332 <code style="color:#806030; ">{</code>
1333 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">on</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code>
1334 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">;</code>
1335 <code style="color:#400000; font-weight:bold; ">else</code>
1336 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1337 <code style="color:#806030; ">}</code>
1339 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
1340 <code style="color:#806030; ">}</code>
1342 <code style="color:#c34e00; ">/*</code>
1343 <code style="color:#c34e00; "> =======================================================================================================================</code>
1344 <code style="color:#c34e00; "> Handler for the "examplePath" directive</code>
1345 <code style="color:#c34e00; "> =======================================================================================================================</code>
1346 <code style="color:#c34e00; "> */</code>
1347 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>example_set_path<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg<code style="color:#806030; ">)</code>
1348 <code style="color:#806030; ">{</code>
1349 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1350 example_config <code style="color:#806030; ">*</code>conf <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> cfg<code style="color:#806030; ">;</code>
1351 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1353 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">)</code>
1354 <code style="color:#806030; ">{</code>
1355 <code style="color:#800040; ">strcpy</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">,</code> arg<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1356 <code style="color:#806030; ">}</code>
1358 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
1359 <code style="color:#806030; ">}</code>
1361 <code style="color:#c34e00; ">/*</code>
1362 <code style="color:#c34e00; "> =======================================================================================================================</code>
1363 <code style="color:#c34e00; "> Handler for the "exampleAction" directive ;</code>
1364 <code style="color:#c34e00; "> Let's pretend this one takes one argument (file or db), and a second (deny or allow), ;</code>
1365 <code style="color:#c34e00; "> and we store it in a bit-wise manner.</code>
1366 <code style="color:#c34e00; "> =======================================================================================================================</code>
1367 <code style="color:#c34e00; "> */</code>
1368 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>example_set_action<code style="color:#806030; ">(</code>cmd_parms <code style="color:#806030; ">*</code>cmd<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>cfg<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg1<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>arg2<code style="color:#806030; ">)</code>
1369 <code style="color:#806030; ">{</code>
1370 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1371 example_config <code style="color:#806030; ">*</code>conf <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> cfg<code style="color:#806030; ">;</code>
1372 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1374 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">)</code>
1375 <code style="color:#806030; ">{</code>
1376 <code style="color:#806030; ">{</code>
1377 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg1<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">file</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code>
1378 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x01</code><code style="color:#806030; ">;</code>
1379 <code style="color:#400000; font-weight:bold; ">else</code>
1380 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x02</code><code style="color:#806030; ">;</code>
1381 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>strcasecmp<code style="color:#806030; ">(</code>arg2<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">deny</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code>
1382 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x10</code><code style="color:#806030; ">;</code>
1383 <code style="color:#400000; font-weight:bold; ">else</code>
1384 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x20</code><code style="color:#806030; ">;</code>
1385 <code style="color:#806030; ">}</code>
1386 <code style="color:#806030; ">}</code>
1388 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
1389 <code style="color:#806030; ">}</code>
1391 <code style="color:#c34e00; ">/*</code>
1392 <code style="color:#c34e00; "> =======================================================================================================================</code>
1393 <code style="color:#c34e00; "> Function for creating new configurations for per-directory contexts</code>
1394 <code style="color:#c34e00; "> =======================================================================================================================</code>
1395 <code style="color:#c34e00; "> */</code>
1396 <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>create_dir_conf<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>context<code style="color:#806030; ">)</code>
1397 <code style="color:#806030; ">{</code>
1398 context <code style="color:#806030; ">=</code> context <code style="color:#806030; ">?</code> context <code style="color:#806030; ">:</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Newly created configuration</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
1400 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1401 example_config <code style="color:#806030; ">*</code>cfg <code style="color:#806030; ">=</code> apr_pcalloc<code style="color:#806030; ">(</code>pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">sizeof</code><code style="color:#806030; ">(</code>example_config<code style="color:#806030; ">)</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1402 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1404 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>cfg<code style="color:#806030; ">)</code>
1405 <code style="color:#806030; ">{</code>
1406 <code style="color:#806030; ">{</code>
1407 <code style="color:#c34e00; ">/* Set some default values */</code>
1408 <code style="color:#800040; ">strcpy</code><code style="color:#806030; ">(</code>cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">context</code><code style="color:#806030; ">,</code> context<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1409 cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1410 <code style="color:#800040; ">memset</code><code style="color:#806030; ">(</code>cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">,</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">,</code> <code style="color:#c00000; ">256</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1411 cfg<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x00</code><code style="color:#806030; ">;</code>
1412 <code style="color:#806030; ">}</code>
1413 <code style="color:#806030; ">}</code>
1415 <code style="color:#400000; font-weight:bold; ">return</code> cfg<code style="color:#806030; ">;</code>
1416 <code style="color:#806030; ">}</code>
1418 <code style="color:#c34e00; ">/*</code>
1419 <code style="color:#c34e00; "> =======================================================================================================================</code>
1420 <code style="color:#c34e00; "> Merging function for configurations</code>
1421 <code style="color:#c34e00; "> =======================================================================================================================</code>
1422 <code style="color:#c34e00; "> */</code>
1423 <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>merge_dir_conf<code style="color:#806030; ">(</code>apr_pool_t <code style="color:#806030; ">*</code>pool<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>BASE<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">void</code> <code style="color:#806030; ">*</code>ADD<code style="color:#806030; ">)</code>
1424 <code style="color:#806030; ">{</code>
1425 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1426 example_config <code style="color:#806030; ">*</code>base <code style="color:#806030; ">=</code> BASE<code style="color:#806030; ">;</code>
1427 example_config <code style="color:#806030; ">*</code>add <code style="color:#806030; ">=</code> ADD<code style="color:#806030; ">;</code>
1428 example_config <code style="color:#806030; ">*</code>conf <code style="color:#806030; ">=</code> create_dir_conf<code style="color:#806030; ">(</code>pool<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">Merged configuration</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1429 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1431 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">=</code><code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">?</code> base<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code> <code style="color:#806030; ">:</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">enabled</code><code style="color:#806030; ">;</code>
1432 conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">=</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">?</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code> <code style="color:#806030; ">:</code> base<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">typeOfAction</code><code style="color:#806030; ">;</code>
1433 <code style="color:#800040; ">strcpy</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">,</code> <code style="color:#800040; ">strlen</code><code style="color:#806030; ">(</code>add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">?</code> add<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code> <code style="color:#806030; ">:</code> base<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">path</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1434 <code style="color:#400000; font-weight:bold; ">return</code> conf<code style="color:#806030; ">;</code>
1435 <code style="color:#806030; ">}</code>
1443 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1444 <div class="section">
1445 <h2><a name="summary" id="summary">Summing up</a></h2>
1447 We have now looked at how to create simple modules for Apache and configuring them. What you do next is entirely up
1448 to you, but it is my hope that something valuable has come out of reading this documentation. If you have questions
1449 on how to further develop modules, you are welcome to join our <a href="http://httpd.apache.org/lists.html">mailing lists</a>
1450 or check out the rest of our documentation for further tips.
1452 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1453 <div class="section">
1454 <h2><a name="snippets" id="snippets">Some useful snippets of code</a></h2>
1456 <h3><a name="get_post" id="get_post">Retrieve a variable from POST form data</a></h3>
1460 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1461 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>read_post_value<code style="color:#806030; ">(</code><code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>key<code style="color:#806030; ">)</code>
1462 <code style="color:#806030; ">{</code>
1463 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1464 <code style="color:#400000; font-weight:bold; ">const</code> apr_array_header_t <code style="color:#806030; ">*</code>fields<code style="color:#806030; ">;</code>
1465 <code style="color:#400000; font-weight:bold; ">int</code> i<code style="color:#806030; ">;</code>
1466 apr_table_entry_t <code style="color:#806030; ">*</code>e <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1467 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1468 e <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>apr_table_entry_t <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> fields<code style="color:#806030; ">-</code><code style="color:#806030; ">></code>elts<code style="color:#806030; ">;</code>
1469 <code style="color:#400000; font-weight:bold; ">for</code><code style="color:#806030; ">(</code>i <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code> i <code style="color:#806030; "><</code> fields<code style="color:#806030; ">-</code><code style="color:#806030; ">></code>nelts<code style="color:#806030; ">;</code> i<code style="color:#806030; ">+</code><code style="color:#806030; ">+</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1470 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">!</code><code style="color:#800040; ">strcmp</code><code style="color:#806030; ">(</code>e<code style="color:#806030; ">[</code>i<code style="color:#806030; ">]</code><code style="color:#806030; ">.</code>key<code style="color:#806030; ">,</code> key<code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#400000; font-weight:bold; ">return</code> e<code style="color:#806030; ">[</code>i<code style="color:#806030; ">]</code><code style="color:#806030; ">.</code>val<code style="color:#806030; ">;</code>
1471 <code style="color:#806030; ">}</code>
1472 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1473 <code style="color:#806030; ">}</code>
1474 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_req <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
1475 <code style="color:#806030; ">{</code>
1476 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~*/</code>
1477 apr_array_header_t <code style="color:#806030; ">*</code>POST<code style="color:#806030; ">;</code>
1478 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>value<code style="color:#806030; ">;</code>
1479 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~*/</code>
1480 ap_parse_form_data<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>POST<code style="color:#806030; ">,</code> <code style="color:#806030; ">-</code><code style="color:#c00000; ">1</code><code style="color:#806030; ">,</code> <code style="color:#c00000; ">8192</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1482 value <code style="color:#806030; ">=</code> read_post_value<code style="color:#806030; ">(</code>POST<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">valueA</code><code style="color:#800000; ">"</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1483 <code style="color:#400000; font-weight:bold; ">if</code> <code style="color:#806030; ">(</code><code style="color:#806030; ">!</code>value<code style="color:#806030; ">)</code> value <code style="color:#806030; ">=</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">(undefined)</code><code style="color:#800000; ">"</code><code style="color:#806030; ">;</code>
1484 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; ">The value of valueA is: </code><code style="color:#0f6900; ">%s</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> value<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1485 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1486 <code style="color:#806030; ">}</code>
1493 <h3><a name="headers_out" id="headers_out">Printing out every HTTP header received</a></h3>
1497 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1498 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_req <code style="color:#806030; ">*</code>r<code style="color:#806030; ">)</code>
1499 <code style="color:#806030; ">{</code>
1500 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1501 <code style="color:#400000; font-weight:bold; ">const</code> apr_array_header_t <code style="color:#806030; ">*</code>fields<code style="color:#806030; ">;</code>
1502 <code style="color:#400000; font-weight:bold; ">int</code> i<code style="color:#806030; ">;</code>
1503 apr_table_entry_t <code style="color:#806030; ">*</code>e <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1504 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1506 fields <code style="color:#806030; ">=</code> <a href="http://apr.apache.org/docs/apr/1.4/group__apr__tables.html#gaea3005541cce67481f48ab201b5c0cf3">apr_table_elts</a><code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code>headers_in<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1507 e <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>apr_table_entry_t <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> fields<code style="color:#806030; ">-</code><code style="color:#806030; ">></code>elts<code style="color:#806030; ">;</code>
1508 <code style="color:#400000; font-weight:bold; ">for</code><code style="color:#806030; ">(</code>i <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code> i <code style="color:#806030; "><</code> fields<code style="color:#806030; ">-</code><code style="color:#806030; ">></code>nelts<code style="color:#806030; ">;</code> i<code style="color:#806030; ">+</code><code style="color:#806030; ">+</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1509 ap_rprintf<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#800000; ">"</code><code style="color:#e60000; "><b></code><code style="color:#0f6900; ">%s</code><code style="color:#e60000; "></b>: </code><code style="color:#0f6900; ">%s</code><code style="color:#e60000; "><br/></code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> e<code style="color:#806030; ">[</code>i<code style="color:#806030; ">]</code><code style="color:#806030; ">.</code>key<code style="color:#806030; ">,</code> e<code style="color:#806030; ">[</code>i<code style="color:#806030; ">]</code><code style="color:#806030; ">.</code>val<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1510 <code style="color:#806030; ">}</code>
1511 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1512 <code style="color:#806030; ">}</code>
1519 <h3><a name="request_body" id="request_body">Reading the request body into memory</a></h3>
1523 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1524 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> util_read<code style="color:#806030; ">(</code>request_rec <code style="color:#806030; ">*</code>r<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code><code style="color:#806030; ">*</code>rbuf<code style="color:#806030; ">,</code> apr_off_t <code style="color:#806030; ">*</code>size<code style="color:#806030; ">)</code>
1525 <code style="color:#806030; ">{</code>
1526 <code style="color:#c34e00; ">/*~~~~~~~~*/</code>
1527 <code style="color:#400000; font-weight:bold; ">int</code> rc <code style="color:#806030; ">=</code> OK<code style="color:#806030; ">;</code>
1528 <code style="color:#c34e00; ">/*~~~~~~~~*/</code>
1530 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">(</code>rc <code style="color:#806030; ">=</code> ap_setup_client_block<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> REQUEST_CHUNKED_ERROR<code style="color:#806030; ">)</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1531 <code style="color:#400000; font-weight:bold; ">return</code><code style="color:#806030; ">(</code>rc<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1532 <code style="color:#806030; ">}</code>
1534 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>ap_should_client_block<code style="color:#806030; ">(</code>r<code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1536 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1537 <code style="color:#400000; font-weight:bold; ">char</code> argsbuffer<code style="color:#806030; ">[</code>HUGE_STRING_LEN<code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
1538 apr_off_t rsize<code style="color:#806030; ">,</code> len_read<code style="color:#806030; ">,</code> rpos <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1539 apr_off_t length <code style="color:#806030; ">=</code> r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">remaining</code><code style="color:#806030; ">;</code>
1540 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1542 <code style="color:#806030; ">*</code>rbuf <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code><code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> apr_pcalloc<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code><code style="color:#008833">pool</code><code style="color:#806030; ">,</code> <code style="color:#806030; ">(</code>apr_size_t<code style="color:#806030; ">)</code> <code style="color:#806030; ">(</code>length <code style="color:#806030; ">+</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1543 <code style="color:#806030; ">*</code>size <code style="color:#806030; ">=</code> length<code style="color:#806030; ">;</code>
1544 <code style="color:#400000; font-weight:bold; ">while</code><code style="color:#806030; ">(</code><code style="color:#806030; ">(</code>len_read <code style="color:#806030; ">=</code> ap_get_client_block<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> argsbuffer<code style="color:#806030; ">,</code> <code style="color:#400000; font-weight:bold; ">sizeof</code><code style="color:#806030; ">(</code>argsbuffer<code style="color:#806030; ">)</code><code style="color:#806030; ">)</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">></code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1545 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code><code style="color:#806030; ">(</code>rpos <code style="color:#806030; ">+</code> len_read<code style="color:#806030; ">)</code> <code style="color:#806030; ">></code> length<code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1546 rsize <code style="color:#806030; ">=</code> length <code style="color:#806030; ">-</code> rpos<code style="color:#806030; ">;</code>
1547 <code style="color:#806030; ">}</code>
1548 <code style="color:#400000; font-weight:bold; ">else</code> <code style="color:#806030; ">{</code>
1549 rsize <code style="color:#806030; ">=</code> len_read<code style="color:#806030; ">;</code>
1550 <code style="color:#806030; ">}</code>
1552 <code style="color:#800040; ">memcpy</code><code style="color:#806030; ">(</code><code style="color:#806030; ">(</code><code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> <code style="color:#806030; ">*</code>rbuf <code style="color:#806030; ">+</code> rpos<code style="color:#806030; ">,</code> argsbuffer<code style="color:#806030; ">,</code> <code style="color:#806030; ">(</code><code style="color:#800040; ">size_t</code><code style="color:#806030; ">)</code> rsize<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1553 rpos <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> rsize<code style="color:#806030; ">;</code>
1554 <code style="color:#806030; ">}</code>
1555 <code style="color:#806030; ">}</code>
1556 <code style="color:#400000; font-weight:bold; ">return</code><code style="color:#806030; ">(</code>rc<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1557 <code style="color:#806030; ">}</code>
1559 <code style="color:#400000; font-weight:bold; ">static</code> <code style="color:#400000; font-weight:bold; ">int</code> example_handler<code style="color:#806030; ">(</code>request_req<code style="color:#806030; ">*</code> r<code style="color:#806030; ">)</code>
1560 <code style="color:#806030; ">{</code>
1561 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~*/</code>
1562 apr_off_t size<code style="color:#806030; ">;</code>
1563 <code style="color:#400000; font-weight:bold; ">const</code> <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>buffer<code style="color:#806030; ">;</code>
1564 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~*/</code>
1566 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>util_read<code style="color:#806030; ">(</code>r<code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>data<code style="color:#806030; ">,</code> <code style="color:#806030; ">&</code>size<code style="color:#806030; ">)</code> <code style="color:#806030; ">=</code><code style="color:#806030; ">=</code> OK<code style="color:#806030; ">)</code> <code style="color:#806030; ">{</code>
1567 ap_rprintf<code style="color:#806030; ">(</code><code style="color:#800000; ">"</code><code style="color:#e60000; ">We read a request body that was </code><code style="color:#0f6900; ">%u</code><code style="color:#e60000; "> bytes long</code><code style="color:#800000; ">"</code><code style="color:#806030; ">,</code> size<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
1568 <code style="color:#806030; ">}</code>
1569 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1570 <code style="color:#806030; ">}</code>
1578 <div class="bottomlang">
1579 <p><span>Available Languages: </span><a href="../en/developer/modguide.html" title="English"> en </a></p>
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1581 <p class="apache">Copyright 2012 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
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