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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
27 <div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#introduction">Introduction</a></li>
28 <li><img alt="" src="../images/down.gif" /> <a href="#basics">Defining a module</a></li>
29 <li><img alt="" src="../images/down.gif" /> <a href="#hooking">Getting started: Hooking into Apache</a></li>
30 <li><img alt="" src="../images/down.gif" /> <a href="#handling">Building a handler</a></li>
31 <li><img alt="" src="../images/down.gif" /> <a href="#configuration">Adding configuration options</a></li>
32 <li><img alt="" src="../images/down.gif" /> <a href="#context">Context aware configurations</a></li>
33 <li><img alt="" src="../images/down.gif" /> <a href="#summary">Summing up</a></li>
34 <li><img alt="" src="../images/down.gif" /> <a href="#snippets">Some useful snippets of code</a></li>
35 </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>
36 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
38 <h2><a name="introduction" id="introduction">Introduction</a></h2>
39 <h3><a name="what" id="what">What we will be discussing in this document</a></h3>
41 This document will discuss how you can easily create modules for the Apache
42 HTTP Server 2.4 ("Apache"), by exploring an example module called
43 <code>mod_example</code>. In the first part of this document, the purpose
44 of this module will be to calculate and print out various digest values for
45 existing files on your web server, whenever we access the URL <code>
46 http://hostname/filename.sum</code>. For instance, if we want to know the
47 MD5 digest value of the file located at <code>
48 http://www.example.com/index.html</code>, we would visit <code>
49 http://www.example.com/index.html.sum</code>.
52 In the second part of this document, which deals with configuration
53 directive and context awareness, we will be looking at a module that simply
54 write out its own configuration to the client.
57 <h3><a name="prerequisites" id="prerequisites">Prerequisites</a></h3>
59 First and foremost, you are expected to have a basic knowledge of how the C
60 programming language works. In most cases, we will try to be as pedagogical
61 as possible and link to documents describing the functions used in the
62 examples, but there are also many cases where it is necessary to either
63 just assume that "it works" or do some digging youself into what the hows
64 and whys of various function calls.
67 Lastly, you will need to have a basic understanding of how modules are
68 loaded and configured in Apache, as well as how to get the headers for
69 Apache if you do not have them already, as these are needed for compiling
73 <h3><a name="compiling" id="compiling">Compiling your module</a></h3>
75 To compile the source code we are building in this document, we will be
76 using <a href="../programs/apxs.html">APXS</a>. Assuming your source file
77 is called mod_example.c, compiling, installing and activating the module is
79 <div class="example"><pre>
80 apxs -i -a -c mod_example.c
84 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
86 <h2><a name="basics" id="basics">Defining a module</a></h2>
87 <img src="../images/build_a_mod_3.png" /><br />
88 <p>Every module starts with the same declaration, or name tag if you will,
89 that defines a module as <em>a separate entity within Apache</em>:
93 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
94 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
95 <code style="color:#806030; ">{</code>
96 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
97 create_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
98 merge_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
99 create_svr_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
100 merge_svr_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
101 directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
102 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
103 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
108 This bit of code lets Apache know that we have now registered a new module
109 in the system, and that its name is <code>example_module</code>. The name
110 of the module is used primarilly for two things:<br />
112 <li>Letting Apache know how to load the module using the LoadModule</li>
113 <li>Setting up a namespace for the module to use in configurations</li>
115 For now, we're only concerned with the first purpose of the module name,
116 which comes into play when we need to load the module:<br />
117 <div class="example"><pre><a href="../mod/mod_so.html#LoadModule">LoadModule</a> example_module modules/mod_example.so</pre></div>
118 In essence, this tells Apache to open up <code>mod_example.so</code> and look for a module
119 called <code>example_module</code>.
122 Within this name tag of ours is also a bunch of references to how we would
123 like to handle things: Which directives do we respond to in a configuration
124 file or .htaccess, how do we operate within specific contexts, and what
125 handlers are we interested in registering with the Apache service. We'll
126 return to all these elements later in this document.
128 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
129 <div class="section">
130 <h2><a name="hooking" id="hooking">Getting started: Hooking into Apache</a></h2>
131 <h3><a name="hook_intro" id="hook_intro">An introduction to hooks</a></h3>
133 When handling requests in Apache, the first thing you will need to do is
134 create a hook into the request handling process. A hook is essentially a
135 message telling Apache that you are willing to either serve or at least
136 take a glance at certain requests given by clients. All handlers, whether
137 it's mod_rewrite, mod_authn_*, mod_proxy and so on, are hooked into
138 specific parts of the request process. As you are probably aware, modules
139 serve different purposes; Some are authentication/authorization handlers,
140 others are file or script handlers while some third modules rewrite URIs or
141 proxies content. Furthermore, in the end, it is up to the user of Apache
142 how and when each module will come into place. Thus, Apache itself does not
143 presume to know which module is responsible for handling a specific
144 request, and will ask each module whether they have an interest in a given
145 request or not. It is then up to each module to either gently decline
146 serving a request, accept serving it or flat out deny the request from
147 being served, as authentication/authorization modules do: <br />
148 <img src="../images/build_a_mod_2.png" /><br />
149 To make it a bit easier for handlers such as our mod_example to know
150 whether the client is requesting content we should handle or not, Apache
151 has directives for hinting to modules whether their assistance is needed or
152 not. Two of these are <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code>
153 and <code class="directive"><a href="../mod/core.html#sethandler">SetHandler</a></code>. Let's take a look at
154 an example using <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code>. In
155 our example case, we want every request ending with .sum to be served by
156 <code>mod_example</code>, so we'll add a configuration directive that tells
157 Apache to do just that:
158 <div class="example"><pre>
159 AddHandler example-handler .sum
161 What this tells Apache is the following: <em>Whenever we receive a request
162 for a URI ending in .sum, we are to let all modules know that we are
163 looking for whoever goes by the name of "example-handler" </em>.
164 Thus, when a request is being served that ends in .sum, Apache will let all
165 modules know, that this request should be served by "example-handler
166 ". As you will see later, when we start building mod_example, we will
167 check for this handler tag relayed by <code>AddHandler</code> and reply to
168 Apache based on the value of this tag.
171 <h3><a name="hook_declaration" id="hook_declaration">Hooking into httpd</a></h3>
173 To begin with, we only want to create a simple handler, that replies to the
174 client browser when a specific URL is requested, so we won't bother setting
175 up configuration handlers and directives just yet. Our initial module
176 definition will look like this:<br />
180 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
181 module AP_MODULE_DECLARE_DATA example_module =
183 STANDARD20_MODULE_STUFF,
184 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
185 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
186 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
187 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
188 <code style="color:#7f0055; font-weight:bold; ">NULL</code>,
189 <code style="color:#800040; ">register_hooks</code> <code style="color:#c34e00; "><code style="color:#c34e00; ">/* Our hook registering function */</code></code>
195 This lets Apache know that we are not interesting in anything fancy, we
196 just want to hook onto the requests and possibly handle some of them. </p>
197 <p> The reference in our example declaration, <code>register_hooks</code>
198 is the name of a function we will create to manage how we hook onto the
199 request process. In this example module, the function has just one purpose;
200 To create a simple hook that gets called after all the rewrites, access
201 control etc has been handled. Thus, we will let Apache know, that we want
202 to hook into its process as one of the last modules:
206 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
207 <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>
208 <code style="color:#806030; ">{</code>
209 <code style="color:#c34e00; ">/* Create a hook in the request handler, so we get called when a request arrives */</code>
210 <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>
211 <code style="color:#806030; ">}</code>
216 The <code>example_handler</code> reference is the function that will handle
217 the request. We will discuss how to create a handler in the next chapter.
220 <h3><a name="hook_others" id="hook_others">Other useful hooks</a></h3>
222 Hooking into the request handling phase is but one of many hooks that you
223 can create. Some other ways of hooking are:
225 <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>
226 <li><code>ap_hook_pre_config</code>: Place a hook that executes before any configuration data has been read (very early hook)</li>
227 <li><code>ap_hook_post_config</code>: Place a hook that executes after configuration has been parsed, but before Apache has forked</li>
228 <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>
232 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
233 <div class="section">
234 <h2><a name="handling" id="handling">Building a handler</a></h2>
236 A handler is essentially a function that receives a callback when a request
237 to Apache is made. It is passed a record of the current request (how it was
238 made, which headers and requests were passed along, who's giving the
239 request and so on), and is put in charge of either telling Apache that it's
240 not interested in the request or handle the request with the tools provided.
242 <h3><a name="simple_handler" id="simple_handler">A simple "Hello, world!"
243 handler</a></h3> Let's start off by making a very simple request handler
244 that does the following: <br />
246 <li>Check that this is a request that should be served by "example-handler"</li>
247 <li>Set the content type of our output to <code>text/html</code></li>
248 <li>Write "Hello, world!" back to the client browser</li>
249 <li>Let Apache know that we took care of this request and everything went fine</li>
251 In C code, our example handler will now look like this:<br />
255 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
256 <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>
257 <code style="color:#806030; ">{</code>
258 <code style="color:#c34e00; ">/* First off, we need to check if this is a call for the "example-handler" handler.</code>
259 <code style="color:#c34e00; "> * If it is, we accept it and do our things, if not, we simply return DECLINED,</code>
260 <code style="color:#c34e00; "> * and Apache will try somewhere else.</code>
261 <code style="color:#c34e00; "> */</code>
262 <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>
264 <code style="color:#c34e00; ">/* Now that we are handling this request, we'll write out "Hello, world!" to the client.</code>
265 <code style="color:#c34e00; "> * To do so, we must first set the appropriate content type, followed by our output.</code>
266 <code style="color:#c34e00; "> */</code>
267 <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>
268 <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>
270 <code style="color:#c34e00; ">/* Lastly, we must tell Apache that we took care of this request and everything went fine.</code>
271 <code style="color:#c34e00; "> * We do so by simply returning the value OK to Apache.</code>
272 <code style="color:#c34e00; "> */</code>
273 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
274 <code style="color:#806030; ">}</code>
279 Now, we put all we have learned together and end up with a program that
281 <a href="http://people.apache.org/~humbedooh/mods/examples/mod_example_1.c">mod_example_1.c</a>
282 . The functions used in this example will be explained later in the section
283 <a href="#functions">"Some useful functions you should know"</a>
284 . <h3><a name="request_rec" id="request_rec">The request_rec structure
285 </a></h3> <p>The most essential part of any request is the <em>request record
286 </em>. In a call to a handler function, this is represented by the <code>
287 request_req* </code> structure passed along with every call that is made.
288 This struct, typically just refered to as <code>r</code> in modules,
289 contains all the information you need for your module to fully process any
290 HTTP request and respond accordingly.</p> <p>Some key elements of the <code>
291 request_req </code> structure are:
293 <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>
294 <li><code><code style="color:#008833">r->method</code> (char*)</code>: Contains the HTTP method being used, f.x. GET or POST</li>
295 <li><code><code style="color:#008833">r->filename</code> (char*)</code>: Contains the translated filename the client is requesting</li>
296 <li><code><code style="color:#008833">r->args</code> (char*)</code>: Contains the query string of the request, if any</li>
297 <li><code><code style="color:#008833">r->headers_in</code> (apr_table_t*)</code>: Contains all the headers sent by the client</li>
298 <li><code><code style="color:#008833">r->connection</code> (conn_rec*)</code>: A record containing information about the current connection</li>
299 <li><code><code style="color:#008833">r->useragent_ip</code> (char*)</code>: The IP address of the client connecting to us</li>
300 <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 "
301 <a href="#memory">Memory management</a>" chapter.</li>
303 A complete list of all the values contained with in the <code>request_req</code> structure can be found in
304 the <a href="http://svn.apache.org/repos/asf/httpd/httpd/trunk/include/httpd.h"><code>httpd.h</code></a> header
305 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>.
308 Let's try out some of these variables in another example handler:<br />
312 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
313 <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>
314 <code style="color:#806030; ">{</code>
315 <code style="color:#c34e00; ">/* Set the appropriate content type */</code>
316 <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>
318 <code style="color:#c34e00; ">/* Print out the IP address of the client connecting to us: */</code>
319 <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>
321 <code style="color:#c34e00; ">/* If we were reached through a GET or a POST request, be happy, else sad. */</code>
322 <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>
323 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>
324 <code style="color:#806030; ">}</code>
325 <code style="color:#400000; font-weight:bold; ">else</code> <code style="color:#806030; ">{</code>
326 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>
327 <code style="color:#806030; ">}</code>
329 <code style="color:#c34e00; ">/* Lastly, if there was a query string, let's print that too! */</code>
330 <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>
331 <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>
332 <code style="color:#806030; ">}</code>
333 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
334 <code style="color:#806030; ">}</code>
342 <h3><a name="return_value" id="return_value">Return values</a></h3>
344 Apache relies on return values from handlers to signify whether a request
345 was handled or not, and if so, whether the request went well or not. If a
346 module is not interested in handling a specific request, it should always
347 return the value <code>DECLINED</code>. If it is handling a request, it
348 should either return the generic value <code>OK</code>, or a specific HTTP
349 status code, for example:
353 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
354 <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>
355 <code style="color:#806030; ">{</code>
356 <code style="color:#c34e00; ">/* Return 404: Not found */</code>
357 <code style="color:#400000; font-weight:bold; ">return</code> HTTP_NOT_FOUND<code style="color:#806030; ">;</code>
358 <code style="color:#806030; ">}</code>
363 Returning <code>OK</code> or a HTTP status code does not necessarilly mean
364 that the request will end. Apache may still have other handlers that are
365 interested in this request, for instance the logging modules which, upon a
366 successful request, will write down a summary of what was requested and how
367 it went. To do a full stop and prevent any further processing after your
368 module is done, you can return the value <code>DONE</code> to let Apache
369 know that it should cease all activity on this request and carry on with
370 the next, without informing other handlers.
372 <strong>General response codes:</strong>
374 <li><code>DECLINED</code>: We are not handling this request</li>
375 <li><code>OK</code>: We handled this request and it went well</li>
376 <li><code>DONE</code>: We handled this request and Apache should just close this thread without further processing</li>
378 <strong>HTTP specific return codes (excerpt):</strong>
380 <li><code>HTTP_OK (200)</code>: Request was okay</li>
381 <li><code>HTTP_MOVED_PERMANENTLY (301)</code>: The resource has moved to a new URL</li>
382 <li><code>HTTP_UNAUTHORIZED (401)</code>: Client is not authorized to visit this page</li>
383 <li><code>HTTP_FORBIDDEN (403)</code>: Permission denied</li>
384 <li><code>HTTP_NOT_FOUND (404)</code>: File not found</li>
385 <li><code>HTTP_INTERNAL_SERVER_ERROR (500)</code>: Internal server error (self explanatory)</li>
390 <h3><a name="functions" id="functions">Some useful functions you should know</a></h3>
394 <code>ap_rputs(const char *string, request_req *r)</code>: <br />
395 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">
400 <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>
407 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__PROTO.html#ga5e91eb6ca777c9a427b2e82bf1eeb81d">ap_rprintf</a></code>: <br />
408 This function works just like <code>printf</code>, except it sends the result to the client.
412 <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>
418 <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 />
419 Sets the content type of the output you are sending.
423 <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>
432 <h3><a name="memory" id="memory">Memory management</a></h3>
434 Managing your resources in Apache is quite easy, thanks to the memory pool
435 system. In essence, each server, connection and request have their own
436 memory pool that gets cleaned up when its scope ends, e.g. when a request
437 is done or when a server process shuts down. All your module needs to do is
438 latch onto this memory pool, and you won't have to worry about having to
439 clean up after yourself - pretty neat, huh?
443 In our module, we will primarilly be allocating memory for each request, so
444 it's appropriate to use the <code style="color:#008833">r->pool</code>
445 reference when creating new objects. A few of the functions for allocating
446 memory within a pool are:
448 <li><code>void* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__pools.html#ga85f1e193c31d109affda72f9a92c6915">apr_palloc</a>(
449 apr_pool_t *p, apr_size_t size)</code>: Allocates <code>size</code> number of bytes in the pool for you</li>
450 <li><code>void* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__pools.html#gaf61c098ad258069d64cdf8c0a9369f9e">apr_pcalloc</a>(
451 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>
452 <li><code>char* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__strings.html#gabc79e99ff19abbd7cfd18308c5f85d47">apr_pstrdup</a>(
453 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>
454 <li><code>char* <a href="http://apr.apache.org/docs/apr/1.4/group__apr__strings.html#ga3eca76b8d293c5c3f8021e45eda813d8">apr_psprintf</a>(
455 apr_pool_t *p, const char *fmt, ...)</code>: Similar to <code>sprintf</code>, except Apache supplies you with an appropriately allocated target variable</li>
458 Let's put these functions into an example handler:<br />
462 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
463 <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>
464 <code style="color:#806030; ">{</code>
465 <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>
466 <code style="color:#400000; font-weight:bold; ">char</code><code style="color:#806030; ">*</code> copy<code style="color:#806030; ">;</code>
467 <code style="color:#400000; font-weight:bold; ">int</code><code style="color:#806030; ">*</code> integers<code style="color:#806030; ">;</code>
469 <code style="color:#c34e00; ">/* Allocate space for 10 integer values and set them all to zero. */</code>
470 integers <code style="color:#806030; ">=</code> apr_pcalloc<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><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><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>
472 <code style="color:#c34e00; ">/* Create a copy of the 'original' variable that we can edit. */</code>
473 copy <code style="color:#806030; ">=</code> apr_pstrdup<code style="color:#806030; ">(</code>r<code style="color:#806030; ">-</code><code style="color:#806030; ">></code>pool<code style="color:#806030; ">,</code> original<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
474 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
475 <code style="color:#806030; ">}</code>
479 This is all well and good for our module, which won't need any
480 pre-initialized variables or structures. However, if we wanted to
481 initialize something early on, before the requests come rolling in, we
482 could simply add a call to a function in our <code>register_hooks</code>
483 function to sort it out:
486 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
487 <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>
488 <code style="color:#806030; ">{</code>
489 <code style="color:#c34e00; ">/* Call a function that initializes some stuff */</code>
490 <code style="color:#800040; ">example_init_function</code><code style="color:#806030; ">(</code>pool<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
491 <code style="color:#c34e00; ">/* Create a hook in the request handler, so we get called when a request arrives */</code>
492 <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>
493 <code style="color:#806030; ">}</code>
497 In this pre-request initialization function we would not be using the
498 same pool as we did when allocating resources for request-based functions.
499 Instead, we would use the pool given to us by Apache for allocating memory
500 on a per-process based level.
505 <h3><a name="parsing" id="parsing">Parsing request data</a></h3>
507 In our example module, we would like to add a feature, that checks which
508 type of digest, MD5 or SHA1 the client would like to see. This could be
509 solved by adding a query string to the request. A query string is typically
510 comprised of several keys and values put together in a string, for instance
511 <code>valueA=yes&valueB=no&valueC=maybe</code>. It is up to the
512 module itself to parse these and get the data it requires. In our example,
513 we'll be looking for a key called <code>digest</code>, and if set to <code>
514 md5</code>, we'll produce an MD5 digest, otherwise we'll produce a SHA1
518 Since the introduction of Apache 2.4, parsing request data from GET and
519 POST requests have never been easier. All we require to parse both GET and
520 POST data is four simple lines:
524 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
525 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__apr__tables.html#gad7ea82d6608a4a633fc3775694ab71e4">apr_table_t</a> *GET;
526 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/structapr__array__header__t.html">apr_array_header_t</a> *POST;
528 <a href="http://ci.apache.org/projects/httpd/trunk/doxygen/group__APACHE__CORE__SCRIPT.html#gaed25877b529623a4d8f99f819ba1b7bd">ap_args_to_table</a>(r, &GET);
529 <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);
534 In our specific example module, we're looking for the <code>digest</code>
535 value from the query string, which now resides inside a table called <code>
536 GET</code>. To extract this value, we need only perform a simple operation:
541 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
542 <code style="color:#c34e00; ">/* Get the "digest" key from the query string, if any. */</code>
543 <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>
545 <code style="color:#c34e00; ">/* If no key was returned, we will set a default value instead. */</code>
546 <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>
552 The structures used for the POST and GET data are not exactly the same, so
553 if we were to fetch a value from POST data instead of the query string, we
554 would have to resort to a few more lines, as outlined in <a href="#get_post">this example</a> in the last chapter of this document.
558 <h3><a name="advanced_handler" id="advanced_handler">Making an advanced handler</a></h3>
559 Now that we have learned how to parse form data and manage our resources,
560 we can move on to creating an advanced version of our module, that spits
561 out the MD5 or SHA1 digest of files:<br />
565 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
566 <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>
567 <code style="color:#806030; ">{</code>
568 <code style="color:#400000; font-weight:bold; ">int</code> rc<code style="color:#806030; ">,</code> exists<code style="color:#806030; ">;</code>
569 apr_finfo_t finfo<code style="color:#806030; ">;</code>
570 apr_file_t<code style="color:#806030; "> *</code>file<code style="color:#806030; ">;</code>
571 <code style="color:#400000; font-weight:bold; ">char</code> <code style="color:#806030; ">*</code>filename<code style="color:#806030; ">;</code>
572 <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>
573 apr_size_t readBytes<code style="color:#806030; ">;</code>
574 <code style="color:#400000; font-weight:bold; ">int</code> n<code style="color:#806030; ">;</code>
575 apr_table_t<code style="color:#806030; "> *</code>GET<code style="color:#806030; ">;</code>
576 apr_array_header_t<code style="color:#806030; "> *</code>POST<code style="color:#806030; ">;</code>
577 <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>
580 <code style="color:#c34e00; ">/* Check that the "example-handler" handler is being called. */</code>
581 <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>
583 <code style="color:#c34e00; ">/* Figure out which file is being requested by removing the .sum from it */</code>
584 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>
585 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>
587 <code style="color:#c34e00; ">/* Figure out if the file we request a sum on exists and isn't a directory */</code>
588 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>
589 <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>
590 exists <code style="color:#806030; ">=</code>
591 <code style="color:#806030; ">(</code>
592 <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>
593 <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>
594 <code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
595 <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>
596 <code style="color:#806030; ">}</code>
597 <code style="color:#c34e00; ">/* If apr_stat failed, we're probably not allowed to check this file. */</code>
598 <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>
600 <code style="color:#c34e00; ">/* Parse the GET and, optionally, the POST data sent to us */</code>
602 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>
603 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>
605 <code style="color:#c34e00; ">/* Set the appropriate content type */</code>
606 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>
608 <code style="color:#c34e00; ">/* Print a title and some general information */</code>
609 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>
610 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>
612 <code style="color:#c34e00; ">/* Get the digest type the client wants to see */</code>
613 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>
614 <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>
617 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>
618 <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>
620 <code style="color:#c34e00; ">/* Are we trying to calculate the MD5 or the SHA1 digest? */</code>
621 <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>
622 <code style="color:#c34e00; ">/* Calculate the MD5 sum of the file */</code>
623 <code style="color:#400000; font-weight:bold; ">union</code> <code style="color:#806030; ">{</code>
624 <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>
625 uint32_t num<code style="color:#806030; ">[</code><code style="color:#c00000; ">4</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
626 <code style="color:#806030; ">}</code> digest<code style="color:#806030; ">;</code>
627 apr_md5_ctx_t md5<code style="color:#806030; ">;</code>
628 apr_md5_init<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>md5<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
629 readBytes <code style="color:#806030; ">=</code> <code style="color:#c00000; ">256</code><code style="color:#806030; ">;</code>
630 <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>
631 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>
632 <code style="color:#806030; ">}</code>
633 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>
635 <code style="color:#c34e00; ">/* Print out the MD5 digest */</code>
636 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>
637 <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>
638 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>
639 <code style="color:#806030; ">}</code>
640 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>
641 <code style="color:#c34e00; ">/* Print a link to the SHA1 version */</code>
642 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>
643 <code style="color:#806030; ">}</code>
644 <code style="color:#400000; font-weight:bold; ">else</code> <code style="color:#806030; ">{</code>
645 <code style="color:#c34e00; ">/* Calculate the SHA1 sum of the file */</code>
646 <code style="color:#400000; font-weight:bold; ">union</code> <code style="color:#806030; ">{</code>
647 <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>
648 uint32_t num<code style="color:#806030; ">[</code><code style="color:#c00000; ">5</code><code style="color:#806030; ">]</code><code style="color:#806030; ">;</code>
649 <code style="color:#806030; ">}</code> digest<code style="color:#806030; ">;</code>
650 apr_sha1_ctx_t sha1<code style="color:#806030; ">;</code>
651 apr_sha1_init<code style="color:#806030; ">(</code><code style="color:#806030; ">&</code>sha1<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
652 readBytes <code style="color:#806030; ">=</code> <code style="color:#c00000; ">256</code><code style="color:#806030; ">;</code>
653 <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>
654 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>
655 <code style="color:#806030; ">}</code>
656 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>
658 <code style="color:#c34e00; ">/* Print out the SHA1 digest */</code>
659 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>
660 <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>
661 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>
662 <code style="color:#806030; ">}</code>
663 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>
665 <code style="color:#c34e00; ">/* Print a link to the MD5 version */</code>
666 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>
667 <code style="color:#806030; ">}</code>
668 apr_file_close<code style="color:#806030; ">(</code>file<code style="color:#806030; ">)</code><code style="color:#806030; ">;</code>
670 <code style="color:#806030; ">}</code>
674 <code style="color:#c34e00; ">/* Let Apache know that we responded to this request. */</code>
675 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
676 <code style="color:#806030; ">}</code>
681 This version in its entirity can be found here:
682 <a href="http://people.apache.org/~humbedooh/mods/examples/mod_example_2.c">mod_example_2.c</a>.
685 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
686 <div class="section">
687 <h2><a name="configuration" id="configuration">Adding configuration options</a></h2>
689 In this next segment of this document, we will turn our eyes away from the
690 digest module and create a new example module, whose only function is to
691 write out its own configuration. The purpose of this is to examine how
692 Apache works with configuration, and what happens when you start writing
693 advanced configurations
696 <h3><a name="config_intro" id="config_intro">An introduction to configuration
697 directives</a></h3> If you are reading this, then you probably already know
698 what a configuration directive is. Simply put, a directive is a way of
699 telling an individual module (or a set of modules) how to behave, such as
700 these directives control how <code>mod_rewrite</code> works:
701 <div class="example"><pre>
703 RewriteCond %{REQUEST_URI} ^/foo/bar
704 RewriteRule ^/foo/bar/(.*)$ /foobar?page=$1
706 Each of these configuration directives are handled by a separate function,
707 that parses the parameters given and sets up a configuration accordingly.
709 <h3><a name="config_simple" id="config_simple">Making an example configuration</a></h3>
710 To begin with, we'll create a basic configuration in C-space:
714 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
715 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
716 <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>
717 <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>
718 <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>
719 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
724 Now, let's put this into perspective by creating a very small module that
725 just prints out a hard-coded configuration. You'll notice that we use the
726 <code>register_hooks</code> function for initializing the configuration
727 values to their defaults:
731 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
732 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
733 <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>
734 <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>
735 <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>
736 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
738 <code style="color:#400000; font-weight:bold; ">static</code> example_config config<code style="color:#806030; ">;</code>
740 <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>
741 <code style="color:#806030; ">{</code>
742 <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>
743 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>
744 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>
745 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>
746 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>
747 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
748 <code style="color:#806030; ">}</code>
750 <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>
751 <code style="color:#806030; ">{</code>
752 config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">;</code>
753 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>
754 config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">0x00</code><code style="color:#806030; ">;</code>
755 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>
756 <code style="color:#806030; ">}</code>
758 <code style="color:#c34e00; ">/* Define our module as an entity and assign a function for registering hooks */</code>
760 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
761 <code style="color:#806030; ">{</code>
762 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
763 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
764 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
765 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
766 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
767 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
768 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
769 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
774 So far so good. To access our new handler, we could add the following to
776 <div class="example"><pre>
777 <Location /example>
778 SetHandler example-handler
781 When we visit, we'll see our current configuration being spit out by our
785 <h3><a name="register_directive" id="register_directive">Registering directives with Apache</a></h3>
786 What if we want to change our configuration, not by hard-coding new values
787 into the module, but by using either the httpd.conf file or possibly a
788 .htaccess file? It's time to let Apache know that we want this to be
789 possible. To do so, we must first change our <em>name tag</em> to include a
790 reference to the configuration directives we want to register with Apache:
794 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
795 module AP_MODULE_DECLARE_DATA example_module =
797 STANDARD20_MODULE_STUFF,
798 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
799 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
800 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
801 <code style="color:#7f0055; font-weight:bold; ">NULL</code>, <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
802 example_directives, <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
803 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
809 This will tell Apache that we are now accepting directives from the
810 configuration files, and that the structure called <code>example_directives
811 </code> holds information on what our directives are and how they work.
812 Since we have three different variables in our module configuration, we
813 will add a structure with three directives and a NULL at the end:
817 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
818 static const command_rec example_directives[] =
820 <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"),
821 <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"),
822 <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!"),
823 { <code style="color:#7f0055; font-weight:bold; ">NULL</code> }
829 <img src="../images/build_a_mod_4.png" border="1" /><br />
831 As you can see, each directive needs at least 5 parameters set:
833 <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.
834 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
835 for more macros).</li>
836 <li><code>exampleEnabled</code>: This is the name of our directive. More precisely, it is what the user must put in his/her
837 configuration in order to invoke a configuration change in our module.</li>
838 <li><code>example_set_enabled</code>: This is a reference to a C function that parses the directive and sets the configuration
839 accordingly. We will discuss how to make this in the following paragraph.</li>
840 <li><code>RSRC_CONF</code>: This tells Apache where the directive is permissable. We'll go into details on this value in the
841 later chapters, but for now, <code>RSRC_CONF</code> means that Apache will only accept these directives in a server context.</li>
842 <li><code>"Enable or disable...."</code>: This is simply a brief description of what the directive does.</li>
844 (<em>The "missing" parameter in our definition, which is usually set to
845 <code>NULL</code>, is an optional function that can be run after the
846 initial function to parse the arguments have been run. This is usually
847 omitted, as the function for verifying arguments might as well be used to
851 <h3><a name="directive_handler" id="directive_handler">The directive handler function</a></h3>
853 Now that we've told Apache to expect some directives for our module, it's
854 time to make a few functions for handling these. What Apache reads in the
855 configuration file(s) is text, and so naturally, what it passes along to
856 our directive handler is one or more strings, that we ourselves need to
857 recognize and act upon. You'll notice, that since we set our <code>
858 exampleAction</code> directive to accept two arguments, its C function also
859 has an additional parameter defined:<br />
862 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
863 <code style="color:#c34e00; ">/* Handler for the "exambleEnabled" directive */</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>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>
865 <code style="color:#806030; ">{</code>
866 <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>
867 <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>
868 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
869 <code style="color:#806030; ">}</code>
871 <code style="color:#c34e00; ">/* Handler for the "examplePath" directive */</code>
872 <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>
873 <code style="color:#806030; ">{</code>
874 config<code style="color:#806030; ">.</code>path <code style="color:#806030; ">=</code> arg<code style="color:#806030; ">;</code>
875 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
876 <code style="color:#806030; ">}</code>
878 <code style="color:#c34e00; ">/* Handler for the "exampleAction" directive */</code>
879 <code style="color:#c34e00; ">/* Let's pretend this one takes one argument (file or db), and a second (deny or allow), */</code>
880 <code style="color:#c34e00; ">/* and we store it in a bit-wise manner. */</code>
881 <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>
882 <code style="color:#806030; ">{</code>
883 <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>
884 <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>
886 <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>
887 <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>
888 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
889 <code style="color:#806030; ">}</code>
896 <h3><a name="directive_complete" id="directive_complete">Putting it all together</a></h3>
898 Now that we have our directives set up, and handlers configured for them,
899 we can assemble our module into one big file:
903 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
904 <code style="color:#c34e00; ">/* mod_example_config_simple.c: */</code>
905 <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>
906 <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>
907 <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>
908 <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>
909 <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>
910 <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>
911 <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>
912 <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>
913 <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>
914 <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>
916 <code style="color:#c34e00; ">/*</code>
917 <code style="color:#c34e00; "> ==============================================================================</code>
918 <code style="color:#c34e00; "> Our configuration prototype and declaration:</code>
919 <code style="color:#c34e00; "> ==============================================================================</code>
920 <code style="color:#c34e00; "> */</code>
921 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
922 <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>
923 <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>
924 <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>
925 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
927 <code style="color:#400000; font-weight:bold; ">static</code> example_config config<code style="color:#806030; ">;</code>
929 <code style="color:#c34e00; ">/*</code>
930 <code style="color:#c34e00; "> ==============================================================================</code>
931 <code style="color:#c34e00; "> Our directive handlers:</code>
932 <code style="color:#c34e00; "> ==============================================================================</code>
933 <code style="color:#c34e00; "> */</code>
934 <code style="color:#c34e00; ">/* Handler for the "exambleEnabled" directive */</code>
935 <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>
936 <code style="color:#806030; ">{</code>
937 <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>
938 <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>
939 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
940 <code style="color:#806030; ">}</code>
942 <code style="color:#c34e00; ">/* Handler for the "examplePath" directive */</code>
943 <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>
944 <code style="color:#806030; ">{</code>
945 config<code style="color:#806030; ">.</code>path <code style="color:#806030; ">=</code> arg<code style="color:#806030; ">;</code>
946 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
947 <code style="color:#806030; ">}</code>
949 <code style="color:#c34e00; ">/* Handler for the "exampleAction" directive */</code>
950 <code style="color:#c34e00; ">/* Let's pretend this one takes one argument (file or db), and a second (deny or allow), */</code>
951 <code style="color:#c34e00; ">/* and we store it in a bit-wise manner. */</code>
952 <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>
953 <code style="color:#806030; ">{</code>
954 <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>
955 <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>
957 <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>
958 <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>
959 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
960 <code style="color:#806030; ">}</code>
962 <code style="color:#c34e00; ">/*</code>
963 <code style="color:#c34e00; "> ==============================================================================</code>
964 <code style="color:#c34e00; "> The directive structure for our name tag:</code>
965 <code style="color:#c34e00; "> ==============================================================================</code>
966 <code style="color:#c34e00; "> */</code>
967 <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>
968 <code style="color:#806030; ">{</code>
969 <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>
970 <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>
971 <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>
972 <code style="color:#806030; ">{</code> <code style="color:#007d45; ">NULL</code> <code style="color:#806030; ">}</code>
973 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
974 <code style="color:#c34e00; ">/*</code>
975 <code style="color:#c34e00; "> ==============================================================================</code>
976 <code style="color:#c34e00; "> Our module handler:</code>
977 <code style="color:#c34e00; "> ==============================================================================</code>
978 <code style="color:#c34e00; "> */</code>
979 <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>
980 <code style="color:#806030; ">{</code>
981 <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>
982 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>
983 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>
984 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>
985 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>
986 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
987 <code style="color:#806030; ">}</code>
989 <code style="color:#c34e00; ">/*</code>
990 <code style="color:#c34e00; "> ==============================================================================</code>
991 <code style="color:#c34e00; "> The hook registration function (also initializes the default config values):</code>
992 <code style="color:#c34e00; "> ==============================================================================</code>
993 <code style="color:#c34e00; "> */</code>
994 <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>
995 <code style="color:#806030; ">{</code>
996 config<code style="color:#806030; ">.</code>enabled <code style="color:#806030; ">=</code> <code style="color:#c00000; ">1</code><code style="color:#806030; ">;</code>
997 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>
998 config<code style="color:#806030; ">.</code>typeOfAction <code style="color:#806030; ">=</code> <code style="color:#c00000; ">3</code><code style="color:#806030; ">;</code>
999 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>
1000 <code style="color:#806030; ">}</code>
1001 <code style="color:#c34e00; ">/*</code>
1002 <code style="color:#c34e00; "> ==============================================================================</code>
1003 <code style="color:#c34e00; "> Our module name tag:</code>
1004 <code style="color:#c34e00; "> ==============================================================================</code>
1005 <code style="color:#c34e00; "> */</code>
1006 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
1007 <code style="color:#806030; ">{</code>
1008 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
1009 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
1010 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
1011 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
1012 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
1013 example_directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
1014 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
1015 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
1022 In our httpd.conf file, we can now change the hard-coded configuration by
1024 <div class="example"><pre>
1026 ExamplePath "/usr/bin/foo"
1027 ExampleAction file allow
1029 And thus we apply the configuration, visit <code>/example</code> on our
1030 web site, and we see the configuration has adapted to what we wrote in our
1036 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1037 <div class="section">
1038 <h2><a name="context" id="context">Context aware configurations</a></h2>
1039 <h3><a name="context_intro" id="context_intro">Introduction to context aware configurations</a></h3>
1041 In Apache, different URLs, virtual hosts, directories etc can have very
1042 different meanings to the user of Apache, and thus different contexts
1043 within which modules must operate. For example, let's assume you have this
1044 configuration set up for mod_rewrite:
1045 <div class="example"><pre>
1046 <Directory "/var/www">
1047 RewriteCond %{HTTP_HOST} ^example.com$
1048 RewriteRule (.*) http://www.example.com/$1
1050 <Directory "/var/www/sub">
1051 RewriteRule ^foobar$ index.php?foobar=true
1054 In this example, you will have set up two different contexts for
1057 <li>Inside <code>/var/www</code>, all requests for <code>http://example.com</code> must go to <code>http://www.example.com</code></li>
1058 <li>Inside <code>/var/www/sub</code>, all requests for <code>foobar</code> must go to <code>index.php?foobar=true</code></li>
1060 If mod_rewrite (or Apache for that matter) wasn't context aware, then
1061 these rewrite rules would just apply to every and any request made,
1062 regardless of where and how they were made, but since the module can pull
1063 the context specific configuration straight from Apache, it does not need
1064 to know itself, which of the directives are valid in this context, since
1065 Apache takes care of this.</p>
1068 So how does a module get the specific configuration for the server,
1069 directory or location in question? It does so by making one simple call:
1073 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1077 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);
1079 That's it! Of course, a whole lot goes on behind the scenes, which we will
1080 discuss in this chapter, starting with how Apache came to know what our
1081 configuration looks like, and how it came to be set up as it is in the
1086 <h3><a name="context_base" id="context_base">Our basic configuration setup</a></h3>
1087 <p>In this chapter, we will be working with a slightly modified version of
1088 our previous context structure. We will set a <code>context</code>
1089 variable that we can use to track which context configuration is being
1090 used by Apache in various places:
1094 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1095 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code> <code style="color:#806030; ">{</code>
1096 <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>
1097 <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>
1098 <code style="color:#400000; font-weight:bold; ">int</code> typeOfAction<code style="color:#806030; ">;</code>
1099 <code style="color:#400000; font-weight:bold; ">int</code> enabled<code style="color:#806030; ">;</code>
1100 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
1107 <p>Our handler for requests will also be modified, yet still very simple:
1111 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1112 <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>
1113 <code style="color:#806030; ">{</code>
1114 <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>
1115 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>
1116 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>
1117 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>
1118 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>
1119 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>
1120 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>
1121 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1122 <code style="color:#806030; ">}</code>
1131 <h3><a name="context_which" id="context_which">Choosing a context</a></h3>
1133 Before we can start making our module context aware, we must first define,
1134 which contexts we will accept. As we saw in the previous chapter, defining
1135 a directive required five elements be set:
1139 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1140 <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"),
1145 The <code>RSRC_CONF</code> definition told Apache that we would only allow
1146 this directive in a global server context, but since we are now trying out
1147 a context aware version of our module, we should set this to something
1148 more lenient, namely the value <code>ACCESS_CONF</code>, which lets us use
1149 the directive inside <Directory> and <Location> blocks.
1153 <h3><a name="context_pool" id="context_pool">Using Apache to allocate configuration slots</a></h3>
1154 <p> A much smarter way to manage your configurations is by letting Apache
1155 help you create them. To do so, we must first start off by changing our
1156 <em>name tag</em> to let Apache know, that it should assist us in creating
1157 and managing our configurations. Since we have chosen the per-directory
1158 (or per-location) context for our module configurations, we'll add a
1159 per-directory creator and merger function reference in our tag:
1162 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1163 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
1164 <code style="color:#806030; ">{</code>
1165 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
1166 create_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
1167 merge_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
1168 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
1169 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
1170 directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
1171 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
1172 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
1183 <h3><a name="context_which" id="context_which">Creating new context configurations</a></h3>
1185 Now that we have told Apache to help us create and manage configurations,
1186 our first step is to make a function for creating new, blank
1187 configurations. We do so by creating the function we just referenced in
1188 our name tag as the Per-directory configuration handler:
1190 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1191 <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>
1192 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>
1193 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>
1194 <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>
1195 <code style="color:#c34e00; ">/* Set some default values */</code>
1196 <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>
1197 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>
1198 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>
1199 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>
1200 <code style="color:#806030; ">}</code>
1201 <code style="color:#400000; font-weight:bold; ">return</code> cfg<code style="color:#806030; ">;</code>
1202 <code style="color:#806030; ">}</code>
1210 <h3><a name="context_which" id="context_which">Merging configurations</a></h3>
1212 Our next step in creating a context aware configuration is merging
1213 configurations. This part of the process particularly apply to scenarios
1214 where you have a parent configuration and a child, such as the following:
1215 <div class="example"><pre>
1216 <Directory "/var/www">
1218 ExamplePath /foo/bar
1219 ExampleAction file allow
1221 <Directory "/var/www/subdir">
1222 ExampleAction file deny
1225 In this example, it is natural to assume that the directory <code>
1226 /var/www/subdir</code> should inherit the value set for the <code>/var/www
1227 </code> directory, as we did not specify a <code>ExampleEnable</code> nor
1228 an <code>ExamplePath</code> for this directory. Apache does not presume to
1229 know if this is true, but cleverly does the following:
1231 <li>Creates a new configuration for <code>/var/www</code></li>
1232 <li>Sets the configuration values according to the directives given for <code>/var/www</code></li>
1233 <li>Creates a new configuration for <code>/var/www/subdir</code></li>
1234 <li>Sets the configuration values according to the directives given for <code>/var/www/subdir</code></li>
1235 <li><strong>Proposes a merge</strong> of the two configurations into a new configuration for <code>/var/www/subdir</code></li>
1237 This proposal is handled by the <code>merge_dir_conf</code> function we
1238 referenced in our name tag. The purpose of this function is to assess the
1239 two configurations and decide how they are to be merged:
1243 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1244 <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>
1245 example_config<code style="color:#806030; ">*</code> base <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> BASE <code style="color:#806030; ">;</code>
1246 example_config<code style="color:#806030; ">*</code> add <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> ADD <code style="color:#806030; ">;</code>
1247 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> 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>
1249 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>
1250 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>
1251 <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>
1253 <code style="color:#400000; font-weight:bold; ">return</code> conf <code style="color:#806030; ">;</code>
1254 <code style="color:#806030; ">}</code>
1261 <h3><a name="context_which" id="context_which">Trying out our new context aware configurations</a></h3>
1263 Now, let's try putting it all together to create a new module that is
1264 context aware. First off, we'll create a configuration that lets us test
1265 how the module works:
1266 <div class="example"><pre>
1267 <Location "/a">
1268 SetHandler example-handler
1270 ExamplePath "/foo/bar"
1271 ExampleAction file allow
1274 <Location "/a/b">
1275 ExampleAction file deny
1279 <Location "/a/b/c">
1280 ExampleAction db deny
1281 ExamplePath "/foo/bar/baz"
1285 Then we'll assemble our module code. Note, that since we are now using our
1286 name tag as reference when fetching configurations in our handler, I have
1287 added some prototypes to keep the compiler happy:
1291 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1292 <code style="color:#c34e00; ">/*$6</code>
1293 <code style="color:#c34e00; "> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</code>
1294 <code style="color:#c34e00; "> * mod_example_config.c</code>
1295 <code style="color:#c34e00; "> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</code>
1296 <code style="color:#c34e00; "> */</code>
1299 <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>
1300 <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>
1301 <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>
1302 <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>
1303 <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>
1304 <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>
1305 <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>
1306 <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>
1307 <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>
1308 <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>
1310 <code style="color:#c34e00; ">/*$1</code>
1311 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1312 <code style="color:#c34e00; "> Configuration structure</code>
1313 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1314 <code style="color:#c34e00; "> */</code>
1316 <code style="color:#400000; font-weight:bold; ">typedef</code> <code style="color:#400000; font-weight:bold; ">struct</code>
1317 <code style="color:#806030; ">{</code>
1318 <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>
1319 <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>
1320 <code style="color:#400000; font-weight:bold; ">int</code> typeOfAction<code style="color:#806030; ">;</code>
1321 <code style="color:#400000; font-weight:bold; ">int</code> enabled<code style="color:#806030; ">;</code>
1322 <code style="color:#806030; ">}</code> example_config<code style="color:#806030; ">;</code>
1324 <code style="color:#c34e00; ">/*$1</code>
1325 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1326 <code style="color:#c34e00; "> Prototypes</code>
1327 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1328 <code style="color:#c34e00; "> */</code>
1330 <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>
1331 <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>
1332 <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>
1333 <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>
1334 <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>
1335 <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>
1336 <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>
1338 <code style="color:#c34e00; ">/*$1</code>
1339 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1340 <code style="color:#c34e00; "> Configuration directives</code>
1341 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1342 <code style="color:#c34e00; "> */</code>
1344 <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>
1345 <code style="color:#806030; ">{</code>
1346 <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>
1347 <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>
1348 <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>
1349 <code style="color:#806030; ">{</code> <code style="color:#007d45; ">NULL</code> <code style="color:#806030; ">}</code>
1350 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
1352 <code style="color:#c34e00; ">/*$1</code>
1353 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1354 <code style="color:#c34e00; "> Our name tag</code>
1355 <code style="color:#c34e00; "> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</code>
1356 <code style="color:#c34e00; "> */</code>
1358 module AP_MODULE_DECLARE_DATA example_module <code style="color:#806030; ">=</code>
1359 <code style="color:#806030; ">{</code>
1360 STANDARD20_MODULE_STUFF<code style="color:#806030; ">,</code>
1361 create_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-directory configuration handler */</code>
1362 merge_dir_conf<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-directory configurations */</code>
1363 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Per-server configuration handler */</code>
1364 <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Merge handler for per-server configurations */</code>
1365 directives<code style="color:#806030; ">,</code> <code style="color:#c34e00; ">/* Any directives we may have for httpd */</code>
1366 register_hooks <code style="color:#c34e00; ">/* Our hook registering function */</code>
1367 <code style="color:#806030; ">}</code><code style="color:#806030; ">;</code>
1369 <code style="color:#c34e00; ">/*</code>
1370 <code style="color:#c34e00; "> =======================================================================================================================</code>
1371 <code style="color:#c34e00; "> Hook registration function</code>
1372 <code style="color:#c34e00; "> =======================================================================================================================</code>
1373 <code style="color:#c34e00; "> */</code>
1374 <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>
1375 <code style="color:#806030; ">{</code>
1376 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>
1377 <code style="color:#806030; ">}</code>
1379 <code style="color:#c34e00; ">/*</code>
1380 <code style="color:#c34e00; "> =======================================================================================================================</code>
1381 <code style="color:#c34e00; "> Our example web service handler</code>
1382 <code style="color:#c34e00; "> =======================================================================================================================</code>
1383 <code style="color:#c34e00; "> */</code>
1384 <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>
1385 <code style="color:#806030; ">{</code>
1386 <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>
1388 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1389 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>
1390 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1392 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>
1393 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>
1394 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>
1395 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>
1396 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>
1397 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1398 <code style="color:#806030; ">}</code>
1400 <code style="color:#c34e00; ">/*</code>
1401 <code style="color:#c34e00; "> =======================================================================================================================</code>
1402 <code style="color:#c34e00; "> Handler for the "exambleEnabled" directive</code>
1403 <code style="color:#c34e00; "> =======================================================================================================================</code>
1404 <code style="color:#c34e00; "> */</code>
1405 <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>
1406 <code style="color:#806030; ">{</code>
1407 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1408 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>
1409 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1411 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">)</code>
1412 <code style="color:#806030; ">{</code>
1413 <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>
1414 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>
1415 <code style="color:#400000; font-weight:bold; ">else</code>
1416 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>
1417 <code style="color:#806030; ">}</code>
1419 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
1420 <code style="color:#806030; ">}</code>
1422 <code style="color:#c34e00; ">/*</code>
1423 <code style="color:#c34e00; "> =======================================================================================================================</code>
1424 <code style="color:#c34e00; "> Handler for the "examplePath" directive</code>
1425 <code style="color:#c34e00; "> =======================================================================================================================</code>
1426 <code style="color:#c34e00; "> */</code>
1427 <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>
1428 <code style="color:#806030; ">{</code>
1429 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1430 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>
1431 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1433 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">)</code>
1434 <code style="color:#806030; ">{</code>
1435 <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>
1436 <code style="color:#806030; ">}</code>
1438 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
1439 <code style="color:#806030; ">}</code>
1441 <code style="color:#c34e00; ">/*</code>
1442 <code style="color:#c34e00; "> =======================================================================================================================</code>
1443 <code style="color:#c34e00; "> Handler for the "exampleAction" directive ;</code>
1444 <code style="color:#c34e00; "> Let's pretend this one takes one argument (file or db), and a second (deny or allow), ;</code>
1445 <code style="color:#c34e00; "> and we store it in a bit-wise manner.</code>
1446 <code style="color:#c34e00; "> =======================================================================================================================</code>
1447 <code style="color:#c34e00; "> */</code>
1448 <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>
1449 <code style="color:#806030; ">{</code>
1450 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1451 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>
1452 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1454 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>conf<code style="color:#806030; ">)</code>
1455 <code style="color:#806030; ">{</code>
1456 <code style="color:#806030; ">{</code>
1457 <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>
1458 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>
1459 <code style="color:#400000; font-weight:bold; ">else</code>
1460 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>
1461 <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>
1462 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>
1463 <code style="color:#400000; font-weight:bold; ">else</code>
1464 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>
1465 <code style="color:#806030; ">}</code>
1466 <code style="color:#806030; ">}</code>
1468 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#007d45; ">NULL</code><code style="color:#806030; ">;</code>
1469 <code style="color:#806030; ">}</code>
1471 <code style="color:#c34e00; ">/*</code>
1472 <code style="color:#c34e00; "> =======================================================================================================================</code>
1473 <code style="color:#c34e00; "> Function for creating new configurations for per-directory contexts</code>
1474 <code style="color:#c34e00; "> =======================================================================================================================</code>
1475 <code style="color:#c34e00; "> */</code>
1476 <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>
1477 <code style="color:#806030; ">{</code>
1478 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>
1480 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1481 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>
1482 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1484 <code style="color:#400000; font-weight:bold; ">if</code><code style="color:#806030; ">(</code>cfg<code style="color:#806030; ">)</code>
1485 <code style="color:#806030; ">{</code>
1486 <code style="color:#806030; ">{</code>
1487 <code style="color:#c34e00; ">/* Set some default values */</code>
1488 <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>
1489 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>
1490 <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>
1491 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>
1492 <code style="color:#806030; ">}</code>
1493 <code style="color:#806030; ">}</code>
1495 <code style="color:#400000; font-weight:bold; ">return</code> cfg<code style="color:#806030; ">;</code>
1496 <code style="color:#806030; ">}</code>
1498 <code style="color:#c34e00; ">/*</code>
1499 <code style="color:#c34e00; "> =======================================================================================================================</code>
1500 <code style="color:#c34e00; "> Merging function for configurations</code>
1501 <code style="color:#c34e00; "> =======================================================================================================================</code>
1502 <code style="color:#c34e00; "> */</code>
1503 <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>
1504 <code style="color:#806030; ">{</code>
1505 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1506 example_config <code style="color:#806030; ">*</code>base <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> BASE<code style="color:#806030; ">;</code>
1507 example_config <code style="color:#806030; ">*</code>add <code style="color:#806030; ">=</code> <code style="color:#806030; ">(</code>example_config <code style="color:#806030; ">*</code><code style="color:#806030; ">)</code> ADD<code style="color:#806030; ">;</code>
1508 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> 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>
1509 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1511 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>
1512 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>
1513 <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>
1514 <code style="color:#400000; font-weight:bold; ">return</code> conf<code style="color:#806030; ">;</code>
1515 <code style="color:#806030; ">}</code>
1523 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1524 <div class="section">
1525 <h2><a name="summary" id="summary">Summing up</a></h2>
1527 We have now looked at how to create simple modules for Apache and
1528 configuring them. What you do next is entirely up to you, but it is my
1529 hope that something valuable has come out of reading this documentation.
1530 If you have questions on how to further develop modules, you are welcome
1531 to join our <a href="http://httpd.apache.org/lists.html">mailing lists</a>
1532 or check out the rest of our documentation for further tips.
1534 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1535 <div class="section">
1536 <h2><a name="snippets" id="snippets">Some useful snippets of code</a></h2>
1538 <h3><a name="get_post" id="get_post">Retrieve a variable from POST form data</a></h3>
1542 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1543 <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>
1544 <code style="color:#806030; ">{</code>
1545 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1546 <code style="color:#400000; font-weight:bold; ">const</code> apr_array_header_t <code style="color:#806030; ">*</code>fields<code style="color:#806030; ">;</code>
1547 <code style="color:#400000; font-weight:bold; ">int</code> i<code style="color:#806030; ">;</code>
1548 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>
1549 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1550 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>
1551 <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>
1552 <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>
1553 <code style="color:#806030; ">}</code>
1554 <code style="color:#400000; font-weight:bold; ">return</code> <code style="color:#c00000; ">0</code><code style="color:#806030; ">;</code>
1555 <code style="color:#806030; ">}</code>
1556 <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>
1557 <code style="color:#806030; ">{</code>
1558 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~*/</code>
1559 apr_array_header_t <code style="color:#806030; ">*</code>POST<code style="color:#806030; ">;</code>
1560 <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>
1561 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~*/</code>
1562 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>
1564 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>
1565 <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>
1566 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>
1567 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1568 <code style="color:#806030; ">}</code>
1575 <h3><a name="headers_out" id="headers_out">Printing out every HTTP header received</a></h3>
1579 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1580 <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>
1581 <code style="color:#806030; ">{</code>
1582 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1583 <code style="color:#400000; font-weight:bold; ">const</code> apr_array_header_t <code style="color:#806030; ">*</code>fields<code style="color:#806030; ">;</code>
1584 <code style="color:#400000; font-weight:bold; ">int</code> i<code style="color:#806030; ">;</code>
1585 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>
1586 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1588 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>
1589 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>
1590 <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>
1591 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>
1592 <code style="color:#806030; ">}</code>
1593 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1594 <code style="color:#806030; ">}</code>
1601 <h3><a name="request_body" id="request_body">Reading the request body into memory</a></h3>
1605 <pre style="color:#000000;background:#ffffef;border: 1px dashed #333; padding: 0.5em; margin: 1em 2em 1em 1em;">
1606 <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>
1607 <code style="color:#806030; ">{</code>
1608 <code style="color:#c34e00; ">/*~~~~~~~~*/</code>
1609 <code style="color:#400000; font-weight:bold; ">int</code> rc <code style="color:#806030; ">=</code> OK<code style="color:#806030; ">;</code>
1610 <code style="color:#c34e00; ">/*~~~~~~~~*/</code>
1612 <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>
1613 <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>
1614 <code style="color:#806030; ">}</code>
1616 <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>
1618 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1619 <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>
1620 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>
1621 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>
1622 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/</code>
1624 <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>
1625 <code style="color:#806030; ">*</code>size <code style="color:#806030; ">=</code> length<code style="color:#806030; ">;</code>
1626 <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>
1627 <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>
1628 rsize <code style="color:#806030; ">=</code> length <code style="color:#806030; ">-</code> rpos<code style="color:#806030; ">;</code>
1629 <code style="color:#806030; ">}</code>
1630 <code style="color:#400000; font-weight:bold; ">else</code> <code style="color:#806030; ">{</code>
1631 rsize <code style="color:#806030; ">=</code> len_read<code style="color:#806030; ">;</code>
1632 <code style="color:#806030; ">}</code>
1634 <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>
1635 rpos <code style="color:#806030; ">+</code><code style="color:#806030; ">=</code> rsize<code style="color:#806030; ">;</code>
1636 <code style="color:#806030; ">}</code>
1637 <code style="color:#806030; ">}</code>
1638 <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>
1639 <code style="color:#806030; ">}</code>
1641 <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>
1642 <code style="color:#806030; ">{</code>
1643 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~*/</code>
1644 apr_off_t size<code style="color:#806030; ">;</code>
1645 <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>
1646 <code style="color:#c34e00; ">/*~~~~~~~~~~~~~~~~*/</code>
1648 <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>
1649 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>
1650 <code style="color:#806030; ">}</code>
1651 <code style="color:#400000; font-weight:bold; ">return</code> OK<code style="color:#806030; ">;</code>
1652 <code style="color:#806030; ">}</code>
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