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diff --git a/rubbos/app/apache2/manual/developer/request.html.en b/rubbos/app/apache2/manual/developer/request.html.en deleted file mode 100644 index 1ac89d24..00000000 --- a/rubbos/app/apache2/manual/developer/request.html.en +++ /dev/null @@ -1,260 +0,0 @@ -<?xml version="1.0" encoding="ISO-8859-1"?> -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> -<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!-- - XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX - This file is generated from xml source: DO NOT EDIT - XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX - --> -<title>Request Processing in Apache 2.0 - Apache HTTP Server</title> -<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> -<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> -<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /> -<link href="../images/favicon.ico" rel="shortcut icon" /></head> -<body id="manual-page"><div id="page-header"> -<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> -<p class="apache">Apache HTTP Server Version 2.0</p> -<img alt="" src="../images/feather.gif" /></div> -<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div> -<div id="path"> -<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 2.0</a> > <a href="./">Developer Documentation</a></div><div id="page-content"><div id="preamble"><h1>Request Processing in Apache 2.0</h1> -<div class="toplang"> -<p><span>Available Languages: </span><a href="../en/developer/request.html" title="English"> en </a></p> -</div> - - <div class="warning"><h3>Warning</h3> - <p>Warning - this is a first (fast) draft that needs further - revision!</p> - </div> - - <p>Several changes in Apache 2.0 affect the internal request - processing mechanics. Module authors need to be aware of these - changes so they may take advantage of the optimizations and - security enhancements.</p> - - <p>The first major change is to the subrequest and redirect - mechanisms. There were a number of different code paths in - Apache 1.3 to attempt to optimize subrequest or redirect - behavior. As patches were introduced to 2.0, these - optimizations (and the server behavior) were quickly broken due - to this duplication of code. All duplicate code has been folded - back into <code>ap_process_request_internal()</code> to prevent - the code from falling out of sync again.</p> - - <p>This means that much of the existing code was 'unoptimized'. - It is the Apache HTTP Project's first goal to create a robust - and correct implementation of the HTTP server RFC. Additional - goals include security, scalability and optimization. New - methods were sought to optimize the server (beyond the - performance of Apache 1.3) without introducing fragile or - insecure code.</p> -</div> -<div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#processing">The Request Processing Cycle</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#parsing">The Request Parsing Phase</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#security">The Security Phase</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#preparation">The Preparation Phase</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#handler">The Handler Phase</a></li> -</ul></div> -<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="processing" id="processing">The Request Processing Cycle</a></h2> - <p>All requests pass through <code>ap_process_request_internal()</code> - in <code>request.c</code>, including subrequests and redirects. If a module - doesn't pass generated requests through this code, the author is cautioned - that the module may be broken by future changes to request - processing.</p> - - <p>To streamline requests, the module author can take advantage - of the hooks offered to drop out of the request cycle early, or - to bypass core Apache hooks which are irrelevant (and costly in - terms of CPU.)</p> -</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="parsing" id="parsing">The Request Parsing Phase</a></h2> - <h3><a name="unescape" id="unescape">Unescapes the URL</a></h3> - <p>The request's <code>parsed_uri</code> path is unescaped, once and only - once, at the beginning of internal request processing.</p> - - <p>This step is bypassed if the proxyreq flag is set, or the - <code>parsed_uri.path</code> element is unset. The module has no further - control of this one-time unescape operation, either failing to - unescape or multiply unescaping the URL leads to security - reprecussions.</p> - - - <h3><a name="strip" id="strip">Strips Parent and This Elements from the - URI</a></h3> - <p>All <code>/../</code> and <code>/./</code> elements are - removed by <code>ap_getparents()</code>. This helps to ensure - the path is (nearly) absolute before the request processing - continues.</p> - - <p>This step cannot be bypassed.</p> - - - <h3><a name="inital-location-walk" id="inital-location-walk">Initial URI Location Walk</a></h3> - <p>Every request is subject to an - <code>ap_location_walk()</code> call. This ensures that - <code class="directive"><a href="../mod/core.html#location"><Location></a></code> sections - are consistently enforced for all requests. If the request is an internal - redirect or a sub-request, it may borrow some or all of the processing - from the previous or parent request's ap_location_walk, so this step - is generally very efficient after processing the main request.</p> - - - <h3><a name="translate_name" id="translate_name">translate_name</a></h3> - <p>Modules can determine the file name, or alter the given URI - in this step. For example, <code class="module"><a href="../mod/mod_vhost_alias.html">mod_vhost_alias</a></code> will - translate the URI's path into the configured virtual host, - <code class="module"><a href="../mod/mod_alias.html">mod_alias</a></code> will translate the path to an alias path, - and if the request falls back on the core, the <code class="directive"><a href="../mod/core.html#documentroot">DocumentRoot</a></code> is prepended to the request resource.</p> - - <p>If all modules <code>DECLINE</code> this phase, an error 500 is - returned to the browser, and a "couldn't translate name" error is logged - automatically.</p> - - - <h3><a name="map_to_storage" id="map_to_storage">Hook: map_to_storage</a></h3> - <p>After the file or correct URI was determined, the - appropriate per-dir configurations are merged together. For - example, <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> compares and merges the appropriate - <code class="directive"><a href="../mod/mod_proxy.html#proxy"><Proxy></a></code> sections. - If the URI is nothing more than a local (non-proxy) <code>TRACE</code> - request, the core handles the request and returns <code>DONE</code>. - If no module answers this hook with <code>OK</code> or <code>DONE</code>, - the core will run the request filename against the <code class="directive"><a href="../mod/core.html#directory"><Directory></a></code> and <code class="directive"><a href="../mod/core.html#files"><Files></a></code> sections. If the request - 'filename' isn't an absolute, legal filename, a note is set for - later termination.</p> - - - <h3><a name="location-walk" id="location-walk">URI Location Walk</a></h3> - <p>Every request is hardened by a second - <code>ap_location_walk()</code> call. This reassures that a - translated request is still subjected to the configured - <code class="directive"><a href="../mod/core.html#location"><Location></a></code> sections. - The request again borrows some or all of the processing from its previous - <code>location_walk</code> above, so this step is almost always very - efficient unless the translated URI mapped to a substantially different - path or Virtual Host.</p> - - - <h3><a name="header_parser" id="header_parser">Hook: header_parser</a></h3> - <p>The main request then parses the client's headers. This - prepares the remaining request processing steps to better serve - the client's request.</p> - -</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="security" id="security">The Security Phase</a></h2> - <p>Needs Documentation. Code is:</p> - - <div class="example"><pre> -switch (ap_satisfies(r)) { -case SATISFY_ALL: -case SATISFY_NOSPEC: - if ((access_status = ap_run_access_checker(r)) != 0) { - return decl_die(access_status, "check access", r); - } - - if (ap_some_auth_required(r)) { - if (((access_status = ap_run_check_user_id(r)) != 0) - || !ap_auth_type(r)) { - return decl_die(access_status, ap_auth_type(r) - ? "check user. No user file?" - : "perform authentication. AuthType not set!", - r); - } - - if (((access_status = ap_run_auth_checker(r)) != 0) - || !ap_auth_type(r)) { - return decl_die(access_status, ap_auth_type(r) - ? "check access. No groups file?" - : "perform authentication. AuthType not set!", - r); - } - } - break; - -case SATISFY_ANY: - if (((access_status = ap_run_access_checker(r)) != 0)) { - if (!ap_some_auth_required(r)) { - return decl_die(access_status, "check access", r); - } - - if (((access_status = ap_run_check_user_id(r)) != 0) - || !ap_auth_type(r)) { - return decl_die(access_status, ap_auth_type(r) - ? "check user. No user file?" - : "perform authentication. AuthType not set!", - r); - } - - if (((access_status = ap_run_auth_checker(r)) != 0) - || !ap_auth_type(r)) { - return decl_die(access_status, ap_auth_type(r) - ? "check access. No groups file?" - : "perform authentication. AuthType not set!", - r); - } - } - break; -}</pre></div> -</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="preparation" id="preparation">The Preparation Phase</a></h2> - <h3><a name="type_checker" id="type_checker">Hook: type_checker</a></h3> - <p>The modules have an opportunity to test the URI or filename - against the target resource, and set mime information for the - request. Both <code class="module"><a href="../mod/mod_mime.html">mod_mime</a></code> and - <code class="module"><a href="../mod/mod_mime_magic.html">mod_mime_magic</a></code> use this phase to compare the file - name or contents against the administrator's configuration and set the - content type, language, character set and request handler. Some modules - may set up their filters or other request handling parameters at this - time.</p> - - <p>If all modules <code>DECLINE</code> this phase, an error 500 is - returned to the browser, and a "couldn't find types" error is logged - automatically.</p> - - - <h3><a name="fixups" id="fixups">Hook: fixups</a></h3> - <p>Many modules are 'trounced' by some phase above. The fixups - phase is used by modules to 'reassert' their ownership or force - the request's fields to their appropriate values. It isn't - always the cleanest mechanism, but occasionally it's the only - option.</p> - -</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="handler" id="handler">The Handler Phase</a></h2> - <p>This phase is <strong>not</strong> part of the processing in - <code>ap_process_request_internal()</code>. Many - modules prepare one or more subrequests prior to creating any - content at all. After the core, or a module calls - <code>ap_process_request_internal()</code> it then calls - <code>ap_invoke_handler()</code> to generate the request.</p> - - <h3><a name="insert_filter" id="insert_filter">Hook: insert_filter</a></h3> - <p>Modules that transform the content in some way can insert - their values and override existing filters, such that if the - user configured a more advanced filter out-of-order, then the - module can move its order as need be. There is no result code, - so actions in this hook better be trusted to always succeed.</p> - - - <h3><a name="hook_handler" id="hook_handler">Hook: handler</a></h3> - <p>The module finally has a chance to serve the request in its - handler hook. Note that not every prepared request is sent to - the handler hook. Many modules, such as <code class="module"><a href="../mod/mod_autoindex.html">mod_autoindex</a></code>, - will create subrequests for a given URI, and then never serve the - subrequest, but simply lists it for the user. Remember not to - put required teardown from the hooks above into this module, - but register pool cleanups against the request pool to free - resources as required.</p> - -</div></div> -<div class="bottomlang"> -<p><span>Available Languages: </span><a href="../en/developer/request.html" title="English"> en </a></p> -</div><div id="footer"> -<p class="apache">Copyright 2009 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> -<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></div> -</body></html>
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