backport LimitInternalRecursion documentation

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/APACHE_2_0_BRANCH@100441 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/docs/manual/mod/core.xml b/docs/manual/mod/core.xml
index 65de4b0b0263dc6853e88649c6549d7bf587d7ed..7ed88838137c0de1d9ce49e7a09e196331f220bb 100644 (file)
--- a/docs/manual/mod/core.xml
+++ b/docs/manual/mod/core.xml
@@ -1516,6 +1516,41 @@ except the named ones</description>
 </usage>
 </directivesynopsis>
 
+<directivesynopsis>
+<name>LimitInternalRecursion</name>
+<description>Determine maximum number of internal redirects and nested
+subrequests</description>
+<syntax>LimitInternalRecursion <var>number</var> [<var>number</var>]</syntax>
+<default>LimitInternalRecursion 10</default>
+<contextlist><context>server config</context><context>virtual host</context>
+</contextlist>
+<compatibility>Available in Apache 2.0.47 and later</compatibility>
+
+<usage>
+    <p>An internal redirect happens, for example, when using the <directive
+    module="mod_actions">Action</directive> directive, which internally
+    redirects the original request to a CGI script. A subrequest is Apache's
+    mechanism to find out what would happen for some URI if it were requested.
+    For example, <module>mod_dir</module> uses subrequests to look for the
+    files listed in the <directive module="mod_dir">DirectoryIndex</directive>
+    directive.</p>
+
+    <p><directive>LimitInternalRecursion</directive> prevents the server
+    from crashing when entering an infinite loop of internal redirects or
+    subrequests. Such loops are usually caused by misconfigurations.</p>
+
+    <p>The directive stores two different limits, which are evaluated on
+    per-request basis. The first <var>number</var> is the maximum number of
+    internal redirects, that may follow each other. The second <var>number</var>
+    determines, how deep subrequests may be nested. If you specify only one
+    <var>number</var>, it will be assigned to both limits.</p>
+
+    <example><title>Example</title>
+      LimitInternalRecursion 5
+    </example>
+</usage>
+</directivesynopsis>
+
 <directivesynopsis>
 <name>LimitRequestBody</name>
 <description>Restricts the total size of the HTTP request body sent