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diff --git a/rubbos/app/apache2/manual/developer/debugging.html.en b/rubbos/app/apache2/manual/developer/debugging.html.en deleted file mode 100644 index 3febd64c..00000000 --- a/rubbos/app/apache2/manual/developer/debugging.html.en +++ /dev/null @@ -1,196 +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>Debugging Memory Allocation in APR - 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>Debugging Memory Allocation in APR</h1> -<div class="toplang"> -<p><span>Available Languages: </span><a href="../en/developer/debugging.html" title="English"> en </a></p> -</div> - - <p>The allocation mechanism's within APR have a number of debugging modes - that can be used to assist in finding memory problems. This document - describes the modes available and gives instructions on activating - them.</p> -</div> -<div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#options">Available debugging options</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#combo">Allowable Combinations</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#howto">Activating Debugging Options</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="options" id="options">Available debugging options</a></h2> - <h3><a name="alloc_debug" id="alloc_debug">Allocation Debugging - ALLOC_DEBUG</a></h3> - - - <div class="note">Debugging support: Define this to enable code which - helps detect re-use of <code>free()</code>d memory and other such - nonsense.</div> - - <p>The theory is simple. The <code>FILL_BYTE</code> (<code>0xa5</code>) - is written over all <code>malloc</code>'d memory as we receive it, and - is written over everything that we free up during a - <code>clear_pool</code>. We check that blocks on the free list always - have the <code>FILL_BYTE</code> in them, and we check during - <code>palloc()</code> that the bytes still have <code>FILL_BYTE</code> - in them. If you ever see garbage URLs or whatnot containing lots - of <code>0xa5</code>s then you know something used data that's been - freed or uninitialized.</p> - - - <h3><a name="alloc_use_malloc" id="alloc_use_malloc">Malloc Support - ALLOC_USE_MALLOC</a></h3> - - - <div class="note">If defined all allocations will be done with - <code>malloc()</code> and <code>free()</code>d appropriately at the - end.</div> - - <p>This is intended to be used with something like Electric - Fence or Purify to help detect memory problems. Note that if - you're using efence then you should also add in <code>ALLOC_DEBUG</code>. - But don't add in <code>ALLOC_DEBUG</code> if you're using Purify because - <code>ALLOC_DEBUG</code> would hide all the uninitialized read errors - that Purify can diagnose.</p> - - - <h3><a name="pool_debug" id="pool_debug">Pool Debugging - POOL_DEBUG</a></h3> - <div class="note">This is intended to detect cases where the wrong pool is - used when assigning data to an object in another pool.</div> - - <p>In particular, it causes the <code>table_{set,add,merge}n</code> - routines to check that their arguments are safe for the - <code>apr_table_t</code> they're being placed in. It currently only works - with the unix multiprocess model, but could be extended to others.</p> - - - <h3><a name="make_table_profile" id="make_table_profile">Table Debugging - MAKE_TABLE_PROFILE</a></h3> - - - <div class="note">Provide diagnostic information about make_table() calls - which are possibly too small.</div> - - <p>This requires a recent gcc which supports - <code>__builtin_return_address()</code>. The error_log output will be a - message such as:</p> - <div class="example"><p><code> - table_push: apr_table_t created by 0x804d874 hit limit of 10 - </code></p></div> - - <p>Use <code>l *0x804d874</code> to find the - source that corresponds to. It indicates that a <code>apr_table_t</code> - allocated by a call at that address has possibly too small an - initial <code>apr_table_t</code> size guess.</p> - - - <h3><a name="alloc_stats" id="alloc_stats">Allocation Statistics - ALLOC_STATS</a></h3> - - - <div class="note">Provide some statistics on the cost of allocations.</div> - - <p>This requires a bit of an understanding of how alloc.c works.</p> - -</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="combo" id="combo">Allowable Combinations</a></h2> - - <p>Not all the options outlined above can be activated at the - same time. the following table gives more information.</p> - - <table class="bordered"><tr class="header"><th /> - <th>ALLOC DEBUG</th> - <th>ALLOC USE MALLOC</th> - <th>POOL DEBUG</th> - <th>MAKE TABLE PROFILE</th> - <th>ALLOC STATS</th></tr> -<tr><th>ALLOC DEBUG</th> - <td>-</td><td>No</td><td>Yes</td><td>Yes</td><td>Yes</td></tr> -<tr class="odd"><th>ALLOC USE MALLOC</th> - <td>No</td><td>-</td><td>No</td><td>No</td><td>No</td></tr> -<tr><th>POOL DEBUG</th> - <td>Yes</td><td>No</td><td>-</td><td>Yes</td><td>Yes</td></tr> -<tr class="odd"><th>MAKE TABLE PROFILE</th> - <td>Yes</td><td>No</td><td>Yes</td><td>-</td><td>Yes</td></tr> -<tr><th>ALLOC STATS</th> - <td>Yes</td><td>No</td><td>Yes</td><td>Yes</td><td>-</td></tr> -</table> - - <p>Additionally the debugging options are not suitable for - multi-threaded versions of the server. When trying to debug - with these options the server should be started in single - process mode.</p> -</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="howto" id="howto">Activating Debugging Options</a></h2> - - <p>The various options for debugging memory are now enabled in - the <code>apr_general.h</code> header file in APR. The various options are - enabled by uncommenting the define for the option you wish to - use. The section of the code currently looks like this - (<em>contained in srclib/apr/include/apr_pools.h</em>)</p> - - <div class="example"><p><code> - /*<br /> - #define ALLOC_DEBUG<br /> - #define POOL_DEBUG<br /> - #define ALLOC_USE_MALLOC<br /> - #define MAKE_TABLE_PROFILE<br /> - #define ALLOC_STATS<br /> - */<br /> - <br /> - typedef struct ap_pool_t {<br /> - <span class="indent"> - union block_hdr *first;<br /> - union block_hdr *last;<br /> - struct cleanup *cleanups;<br /> - struct process_chain *subprocesses;<br /> - struct ap_pool_t *sub_pools;<br /> - struct ap_pool_t *sub_next;<br /> - struct ap_pool_t *sub_prev;<br /> - struct ap_pool_t *parent;<br /> - char *free_first_avail;<br /> - </span> - #ifdef ALLOC_USE_MALLOC<br /> - <span class="indent"> - void *allocation_list;<br /> - </span> - #endif<br /> - #ifdef POOL_DEBUG<br /> - <span class="indent"> - struct ap_pool_t *joined;<br /> - </span> - #endif<br /> - <span class="indent"> - int (*apr_abort)(int retcode);<br /> - struct datastruct *prog_data;<br /> - </span> - } ap_pool_t; - </code></p></div> - - <p>To enable allocation debugging simply move the <code>#define - ALLOC_DEBUG</code> above the start of the comments block and rebuild - the server.</p> - - <div class="note"><h3>Note</h3> - <p>In order to use the various options the server <strong>must</strong> - be rebuilt after editing the header file.</p> - </div> -</div></div> -<div class="bottomlang"> -<p><span>Available Languages: </span><a href="../en/developer/debugging.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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