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diff --git a/docs/manual/developer/modules.html.en b/docs/manual/developer/modules.html.en deleted file mode 100644 index ebf7c33da2..0000000000 --- a/docs/manual/developer/modules.html.en +++ /dev/null @@ -1,258 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" - "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> - -<html xmlns="http://www.w3.org/1999/xhtml"> - <head> - <meta name="generator" content="HTML Tidy, see www.w3.org" /> - - <title>Converting Modules from Apache 1.3 to Apache 2.0</title> - </head> - <!-- Background white, links blue (unvisited), navy (visited), red (active) --> - - <body bgcolor="#FFFFFF" text="#000000" link="#0000FF" - vlink="#000080" alink="#FF0000"> - <!--#include virtual="header.html" --> - - <h1 align="CENTER">From Apache 1.3 to Apache 2.0<br /> - Modules</h1> - - <p>This is a first attempt at writing the lessons I learned - when trying to convert the mod_mmap_static module to Apache - 2.0. It's by no means definitive and probably won't even be - correct in some ways, but it's a start.</p> - <hr /> - - <h2>The easier changes...</h2> - - <h3>Cleanup Routines</h3> - - <p>These now need to be of type apr_status_t and return a value - of that type. Normally the return value will be APR_SUCCESS - unless there is some need to signal an error in the cleanup. Be - aware that even though you signal an error not all code yet - checks and acts upon the error.</p> - - <h3>Initialisation Routines</h3> - - <p>These should now be renamed to better signify where they sit - in the overall process. So the name gets a small change from - mmap_init to mmap_post_config. The arguments passed have - undergone a radical change and now look like</p> - - <ul style="list-style:none"> - <li>apr_pool_t *p,</li> - - <li>apr_pool_t *plog,</li> - - <li>apr_pool_t *ptemp,</li> - - <li>server_rec *s</li> - </ul> - - <h3>Data Types</h3> - - <p>A lot of the data types have been moved into the APR. This - means that some have had a name change, such as the one shown - above. The following is a brief list of some of the changes - that you are likely to have to make.</p> - - <ul style="list-style:none"> - <li>pool becomes apr_pool_t</li> - - <li>table becomes apr_table_t</li> - </ul> - <hr /> - - <h2>The <em>messier</em> changes...</h2> - - <h3>Register Hooks</h3> - - <p>The new architecture uses a series of hooks to provide for - calling your functions. These you'll need to add to your module - by way of a new function, static void register_hooks(void). The - function is really reasonably straightforward once you - understand what needs to be done. Each function that needs - calling at some stage in the processing of a request needs to - be registered, handlers do not. There are a number of phases - where functions can be added, and for each you can specify with - a high degree of control the relative order that the function - will be called in.</p> - - <p>This is the code that was added to mod_mmap_static:</p> -<pre> -static void register_hooks(void) -{ - static const char * const aszPre[]={ "http_core.c",NULL }; - ap_hook_post_config(mmap_post_config,NULL,NULL,HOOK_MIDDLE); - ap_hook_translate_name(mmap_static_xlat,aszPre,NULL,HOOK_LAST); -}; -</pre> - - <p>This registers 2 functions that need to be called, one in - the post_config stage (virtually every module will need this - one) and one for the translate_name phase. note that while - there are different function names the format of each is - identical. So what is the format?</p> - - <p><strong>ap_hook_[phase_name](function_name, predecessors, - successors, position);</strong></p> - - <p>There are 3 hook positions defined...</p> - - <ul style="list-style:none"> - <li>HOOK_FIRST</li> - - <li>HOOK_MIDDLE</li> - - <li>HOOK_LAST</li> - </ul> - - <p>To define the position you use the position and then modify - it with the predecessors and successors. each of the modifiers - can be a list of functions that should be called, either before - the function is run (predecessors) or after the function has - run (successors).</p> - - <p>In the mod_mmap_static case I didn't care about the - post_config stage, but the mmap_static_xlat MUST be called - after the core module had done it's name translation, hence the - use of the aszPre to define a modifier to the position - HOOK_LAST.</p> - - <h3>Module Definition</h3> - - <p>There are now a lot fewer stages to worry about when - creating your module definition. The old defintion looked - like</p> -<pre> -module MODULE_VAR_EXPORT [module_name]_module = -{ - STANDARD_MODULE_STUFF, - /* initializer */ - /* dir config creater */ - /* dir merger --- default is to override */ - /* server config */ - /* merge server config */ - /* command handlers */ - /* handlers */ - /* filename translation */ - /* check_user_id */ - /* check auth */ - /* check access */ - /* type_checker */ - /* fixups */ - /* logger */ - /* header parser */ - /* child_init */ - /* child_exit */ - /* post read-request */ -}; -</pre> - - <p>The new structure is a great deal simpler...</p> -<pre> -module MODULE_VAR_EXPORT [module_name]_module = -{ - STANDARD20_MODULE_STUFF, - /* create per-directory config structures */ - /* merge per-directory config structures */ - /* create per-server config structures */ - /* merge per-server config structures */ - /* command handlers */ - /* handlers */ - /* register hooks */ - }; -</pre> - - <p>Some of these read directly across, some don't. I'll try to - summarise what should be done below.</p> - - <p>The stages that read directly across :</p> - - <ul style="list-style:none"> - <li>/* dir config creater */ ==> /* create per-directory - config structures */</li> - - <li>/* server config */ ==> /* create per-server config - structures */</li> - - <li>/* dir merger */ ==> /* merge per-directory config - structures */</li> - - <li>/* merge server config */ ==> /* merge per-server - config structures */</li> - - <li>/* command table */ ==> /* command apr_table_t */</li> - - <li>/* handlers */ ==> /* handlers */</li> - </ul> - - <p>The remainder of the old functions should be registered as - hooks. There are the following hook stages defined so - far...</p> - - <ul style="list-style:none"> - <li>ap_hook_post_config <em>(this is where the old _init - routines get registered)</em></li> - - <li>ap_hook_http_method <em>(retrieve the http method from a - request. (legacy))</em></li> - - <li>ap_hook_open_logs <em>(open any specified logs)</em></li> - - <li>ap_hook_auth_checker <em>(check if the resource requires - authorization)</em></li> - - <li>ap_hook_access_checker <em>(check for module-specific - restrictions)</em></li> - - <li>ap_hook_check_user_id <em>(check the user-id and - password)</em></li> - - <li>ap_hook_default_port <em>(retrieve the default port for - the server)</em></li> - - <li>ap_hook_pre_connection <em>(do any setup required just - before processing, but after accepting)</em></li> - - <li>ap_hook_process_connection <em>(run the correct - protocol)</em></li> - - <li>ap_hook_child_init <em>(call as soon as the child is - started)</em></li> - - <li>ap_hook_create_request <em>(??)</em></li> - - <li>ap_hook_fixups <em>(last chance to modify things before - generating content)</em></li> - - <li>ap_hook_handler <em>(generate the content)</em></li> - - <li>ap_hook_header_parser <em>(let's modules look at the - headers, not used by most modules, because they use - post_read_request for this.)</em></li> - - <li>ap_hook_insert_filter <em>(to insert filters into the - filter chain)</em></li> - - <li>ap_hook_log_transaction <em>(log information about the - request)</em></li> - - <li>ap_hook_optional_fn_retrieve <em>(retrieve any functions - registered as optional)</em></li> - - <li>ap_hook_post_read_request <em>(called after reading the - request, before any other phase)</em></li> - - <li>ap_hook_quick_handler <em>(??)</em></li> - - <li>ap_hook_translate_name <em>(translate the URI into a - filename)</em></li> - - <li>ap_hook_type_checker <em>(determine and/or set the doc - type)</em> <!--#include virtual="footer.html" --> - </li> - </ul> - </body> -</html> - |