Collaboration diagram for Apache Hooks:

Functions
int	mpm (apr_pool_t pconf, apr_pool_t plog, server_rec *server_conf)

void	child_status (server_rec *s, pid_t pid, ap_generation_t gen, int slot, mpm_child_status state)

void	end_generation (server_rec *s, ap_generation_t gen)

int	header_parser (request_rec *r)

int	pre_config (apr_pool_t pconf, apr_pool_t plog, apr_pool_t *ptemp)

int	check_config (apr_pool_t pconf, apr_pool_t plog, apr_pool_t ptemp, server_rec s)

void	test_config (apr_pool_t pconf, server_rec s)

int	post_config (apr_pool_t pconf, apr_pool_t plog, apr_pool_t ptemp, server_rec s)

int	open_logs (apr_pool_t pconf, apr_pool_t plog, apr_pool_t ptemp, server_rec s)

void	child_init (apr_pool_t pchild, server_rec s)

int	handler (request_rec *r)

int	quick_handler (request_rec *r, int lookup_uri)

void	optional_fn_retrieve (void)

apr_status_t	open_htaccess (request_rec r, const char dir_name, const char access_name, ap_configfile_t conffile, const char *full_name)

int	get_mgmt_items (apr_pool_t p, const char val, apr_hash_t *ht)

void	error_log (const ap_errorlog_info info, const char errstr)

int	generate_log_id (const conn_rec c, const request_rec r, const char **id)

void	insert_error_filter (request_rec *r)

int	create_request (request_rec *r)

int	pre_translate_name (request_rec *r)

int	translate_name (request_rec *r)

int	map_to_storage (request_rec *r)

int	check_user_id (request_rec *r)

int	fixups (request_rec *r)

int	type_checker (request_rec *r)

int	access_checker (request_rec *r)

int	access_checker_ex (request_rec *r)

int	auth_checker (request_rec *r)

void	insert_filter (request_rec *r)

int	post_perdir_config (request_rec *r)

int	force_authn (request_rec *r)

apr_status_t	dirwalk_stat (apr_finfo_t finfo, request_rec r, apr_int32_t wanted)

int	ssl_conn_is_ssl (conn_rec *c)

const char *	ssl_var_lookup (apr_pool_t p, server_rec s, conn_rec c, request_rec r, const char *name)

int	monitor (apr_pool_t p, server_rec s)

int	mpm_query (int query_code, int result, apr_status_t rv)

apr_status_t	mpm_register_timed_callback (apr_time_t t, ap_mpm_callback_fn_t cbfn, void baton)

apr_status_t	mpm_register_poll_callback (apr_pool_t p, const apr_array_header_t pds, ap_mpm_callback_fn_t cbfn, void baton)

apr_status_t	mpm_resume_suspended (conn_rec *)

const char *	mpm_get_name (void)

int	output_pending (conn_rec *c)

int	input_pending (conn_rec *c)

void	suspend_connection (conn_rec c, request_rec r)

void	resume_connection (conn_rec c, request_rec r)

int	pre_mpm (apr_pool_t *p, ap_scoreboard_e sb_type)

Detailed Description

Function Documentation

◆ access_checker()

int access_checker ( request_rec * r )

This hook is used to apply additional access control to this resource. It runs before a user is authenticated, so this hook is really to apply additional restrictions independent of a user. It also runs independent of 'Require' directive usage. This hook should be registered with ap_hook_check_access().

Parameters

r	the current request

Returns: OK, DECLINED, or HTTP_...

See also: ap_hook_check_access

◆ access_checker_ex()

int access_checker_ex ( request_rec * r )

This hook is used to apply additional access control and/or bypass authentication for this resource. It runs before a user is authenticated, but after the access_checker hook. This hook should be registered with ap_hook_check_access_ex(). If "Satisfy any" is in effect, this hook may be skipped.

Parameters

r	the current request

Returns: OK (allow access), DECLINED (let later modules decide), or HTTP_... (deny access)

See also: ap_hook_check_access_ex

◆ auth_checker()

int auth_checker ( request_rec * r )

This hook is used to check to see if the resource being requested is available for the authenticated user (r->user and r->ap_auth_type). It runs after the access_checker and check_user_id hooks. Note that it will only be called if Apache determines that access control has been applied to this resource (through a 'Require' directive). This hook should be registered with ap_hook_check_authz(). If "Satisfy any" is in effect, this hook may be skipped.

Parameters

r	the current request

Returns: OK, DECLINED, or HTTP_...

See also: ap_hook_check_authz

◆ check_config()

int check_config	(	apr_pool_t *	pconf,
		apr_pool_t *	plog,
		apr_pool_t *	ptemp,
		server_rec *	s
	)

Run the check_config function for each module

Parameters

pconf	The config pool
plog	The logging streams pool
ptemp	The temporary pool
s	the server to operate upon

Returns: OK or DECLINED on success anything else is a error

◆ check_user_id()

int check_user_id ( request_rec * r )

This hook is used to analyze the request headers, authenticate the user, and set the user information in the request record (r->user and r->ap_auth_type). This hook is only run when Apache determines that authentication/authorization is required for this resource (as determined by the 'Require' directive). It runs after the access_checker hook, and before the auth_checker hook. This hook should be registered with ap_hook_check_authn(). If "Satisfy any" is in effect, this hook may be skipped.

Parameters

r	The current request

Returns: OK, DECLINED, or HTTP_...

See also: ap_hook_check_authn

◆ child_init()

void child_init	(	apr_pool_t *	pchild,
		server_rec *	s
	)

Run the child_init functions for each module

Parameters

pchild	The child pool
s	The list of server_recs in this server

◆ child_status()

void child_status	(	server_rec *	s,
		pid_t	pid,
		ap_generation_t	gen,
		int	slot,
		mpm_child_status	state
	)

Allow a module to remain aware of MPM child process state changes, along with the generation and scoreboard slot of the process changing state.

With some MPMs (event and worker), an active MPM child process may lose its scoreboard slot if the child process is exiting and the scoreboard slot is needed by other processes. When this occurs, the hook will be called with the MPM_CHILD_LOST_SLOT state.

Parameters

s	The main server_rec.
pid	The id of the MPM child process.
gen	The server generation of that child process.
slot	The scoreboard slot number, or -1. It will be -1 when an MPM child process exits, and that child had previously lost its scoreboard slot.
state	One of the mpm_child_status values. Modules should ignore unrecognized values.

◆ create_request()

int create_request ( request_rec * r )

Gives modules a chance to create their request_config entry when the request is created.

Parameters

r	The current request

◆ dirwalk_stat()

apr_status_t dirwalk_stat	(	apr_finfo_t *	finfo,
		request_rec *	r,
		apr_int32_t	wanted
	)

This hook allows modules to handle/emulate the apr_stat() calls needed for directory walk.

Parameters

finfo	where to put the stat data
r	The current request
wanted	APR_FINFO_* flags to pass to apr_stat()

Returns: apr_status_t or AP_DECLINED (let later modules decide)

◆ end_generation()

void end_generation	(	server_rec *	s,
		ap_generation_t	gen
	)

Allow a module to be notified when the last child process of a generation exits.

Parameters

s	The main server_rec.
gen	The server generation which is now completely finished.

◆ error_log()

void error_log	(	const ap_errorlog_info *	info,
		const char *	errstr
	)

hook method to log error messages

Parameters

info	pointer to ap_errorlog_info struct which contains all the details
errstr	the (unformatted) message to log

Warning: Allocating from the usual pools (pool, info->c->pool, info->p->pool) must be avoided because it can cause memory leaks. Use a subpool if necessary.

◆ fixups()

int fixups ( request_rec * r )

Allows modules to perform module-specific fixing of header fields. This is invoked just before any content-handler

Parameters

r	The current request

Returns: OK, DECLINED, or HTTP_...

◆ force_authn()

int force_authn ( request_rec * r )

This hook allows a module to force authn to be required when processing a request. This hook should be registered with ap_hook_force_authn().

Parameters

r	The current request

Returns: OK (force authn), DECLINED (let later modules decide)

◆ generate_log_id()

int generate_log_id	(	const conn_rec *	c,
		const request_rec *	r,
		const char **	id
	)

hook method to generate unique id for connection or request

Parameters

c	the conn_rec of the connections
r	the request_req (may be NULL)
id	the place where to store the unique id

Returns: OK or DECLINE

◆ get_mgmt_items()

int get_mgmt_items	(	apr_pool_t *	p,
		const char *	val,
		apr_hash_t *	ht
	)

This hook provdes a way for modules to provide metrics/statistics about their operational status.

Parameters

p	A pool to use to create entries in the hash table
val	The name of the parameter(s) that is wanted. This is tree-structured would be in the form ('' is all the tree, 'module.' all of the module , 'module.foo.*', or 'module.foo.bar' )
ht	The hash table to store the results. Keys are item names, and the values point to ap_mgmt_item_t structures.

◆ handler()

int handler ( request_rec * r )

Run the handler functions for each module

Parameters

r	The request_rec

Remarks: non-wildcard handlers should HOOK_MIDDLE, wildcard HOOK_LAST

◆ header_parser()

int header_parser ( request_rec * r )

Run the header parser functions for each module

Parameters

r	The current request

Returns: OK or DECLINED

◆ input_pending()

int input_pending ( conn_rec * c )

Hook called to determine whether any data is pending in the input filters.

Parameters

c	The current connection

Returns: OK if we can read without blocking, DECLINED if a read would block.

◆ insert_error_filter()

void insert_error_filter ( request_rec * r )

This hook allows modules to insert filters for the current error response

Parameters

r	the current request

◆ insert_filter()

void insert_filter ( request_rec * r )

This hook allows modules to insert filters for the current request

Parameters

r	the current request

◆ map_to_storage()

int map_to_storage ( request_rec * r )

This hook allow modules to set the per_dir_config based on their own context (such as "<Proxy>" sections) and responds to contextless requests such as TRACE that need no security or filesystem mapping. based on the filesystem.

Parameters

r	The current request

Returns: DONE (or HTTP_) if this contextless request was just fulfilled (such as TRACE), OK if this is not a file, and DECLINED if this is a file. The core map_to_storage (HOOK_RUN_REALLY_LAST) will directory_walk and file_walk the r->filename.

◆ monitor()

int monitor	(	apr_pool_t *	p,
		server_rec *	s
	)

This hook allows modules to be called at intervals by some MPMs in the parent process. IOW, this is not portable to all platforms or MPMs.

Parameters

p	The pconf pool
s	The main server

Returns: OK or DECLINED (errors are ignored)

◆ mpm()

int mpm	(	apr_pool_t *	pconf,
		apr_pool_t *	plog,
		server_rec *	server_conf
	)

Pass control to the MPM for steady-state processing. It is responsible for controlling the parent and child processes. It will run until a restart/shutdown is indicated.

Parameters

pconf	the configuration pool, reset before the config file is read
plog	the log pool, reset after the config file is read
server_conf	the global server config.

Returns: DONE for shutdown OK otherwise.

◆ mpm_get_name()

const char* mpm_get_name ( void )

Get MPM name (e.g., "prefork" or "event")

◆ mpm_query()

int mpm_query	(	int	query_code,
		int *	result,
		apr_status_t *	rv
	)

implement the ap_mpm_query() function The MPM should return OK+APR_ENOTIMPL for any unimplemented query codes; modules which intercede for specific query codes should DECLINE for others.

◆ mpm_register_poll_callback()

apr_status_t mpm_register_poll_callback	(	apr_pool_t *	p,
		const apr_array_header_t *	pds,
		ap_mpm_callback_fn_t *	cbfn,
		void *	baton
	)

register the specified callback

◆ mpm_register_timed_callback()

apr_status_t mpm_register_timed_callback	(	apr_time_t	t,
		ap_mpm_callback_fn_t *	cbfn,
		void *	baton
	)

register the specified callback

◆ mpm_resume_suspended()

apr_status_t mpm_resume_suspended ( conn_rec * )

Resume the suspended connection

◆ open_htaccess()

apr_status_t open_htaccess	(	request_rec *	r,
		const char *	dir_name,
		const char *	access_name,
		ap_configfile_t **	conffile,
		const char **	full_name
	)

Allow modules to open htaccess files or perform operations before doing so

Parameters

r	The current request
dir_name	The directory for which the htaccess file should be opened
access_name	The filename for which the htaccess file should be opened
conffile	Where the pointer to the opened ap_configfile_t must be stored
full_name	Where the full file name of the htaccess file must be stored.

Returns: APR_SUCCESS on success, APR_ENOENT or APR_ENOTDIR if no htaccess file exists, AP_DECLINED to let later modules do the opening, any other error code on error.

◆ open_logs()

int open_logs	(	apr_pool_t *	pconf,
		apr_pool_t *	plog,
		apr_pool_t *	ptemp,
		server_rec *	s
	)

Run the open_logs functions for each module

Parameters

pconf	The config pool
plog	The logging streams pool
ptemp	The temporary pool
s	The list of server_recs

Returns: OK or DECLINED on success anything else is a error

◆ optional_fn_retrieve()

void optional_fn_retrieve ( void )

Retrieve the optional functions for each module. This is run immediately before the server starts. Optional functions should be registered during the hook registration phase.

◆ output_pending()

int output_pending ( conn_rec * c )

Hook called to determine whether we should stay within the write completion phase.

Parameters

c	The current connection

Returns: OK if write completion should continue, DECLINED if write completion should end gracefully, or a positive error if we should begin to linger.

◆ post_config()

int post_config	(	apr_pool_t *	pconf,
		apr_pool_t *	plog,
		apr_pool_t *	ptemp,
		server_rec *	s
	)

Run the post_config function for each module

The function might be called multiple times. pconf, plog, and ptemp may be cleared and/or destroyed between calls.

The function will be called zero or one times with the server's state being AP_SQ_MS_CREATE_PRE_CONFIG, and will be called one or more times with the server's state being AP_SQ_MS_CREATE_CONFIG.

See also: ap_state_query(), AP_SQ_MAIN_STATE

Parameters

pconf	The config pool
plog	The logging streams pool
ptemp	The temporary pool
s	The list of server_recs

Returns: OK or DECLINED on success anything else is a error

◆ post_perdir_config()

int post_perdir_config ( request_rec * r )

This hook allows modules to affect the request immediately after the per-directory configuration for the request has been generated.

Parameters

r	The current request

Returns: OK (allow access), DECLINED (let later modules decide), or HTTP_... (deny access)

◆ pre_config()

int pre_config	(	apr_pool_t *	pconf,
		apr_pool_t *	plog,
		apr_pool_t *	ptemp
	)

Run the pre_config function for each module

Parameters

pconf	The config pool
plog	The logging streams pool
ptemp	The temporary pool

Returns: OK or DECLINED on success anything else is a error

◆ pre_mpm()

int pre_mpm	(	apr_pool_t *	p,
		ap_scoreboard_e	sb_type
	)

Hook for post scoreboard creation, pre mpm.

Parameters

p	Apache pool to allocate from.
sb_type

Returns: OK or DECLINE on success; anything else is a error

◆ pre_translate_name()

int pre_translate_name ( request_rec * r )

This hook allow modules an opportunity to translate the URI into an actual filename, before URL decoding happens.

Parameters

r	The current request

Returns: DECLINED to let other modules handle the pre-translation, OK if it was handled and no other module should process it, DONE if no further transformation should happen on the URI, HTTP_... in case of error.

◆ quick_handler()

int quick_handler	(	request_rec *	r,
		int	lookup_uri
	)

Run the quick handler functions for each module. The quick_handler is run before any other requests hooks are called (location_walk, directory_walk, access checking, et. al.). This hook was added to provide a quick way to serve content from a URI keyed cache.

Parameters

r	The request_rec
lookup_uri	Controls whether the caller actually wants content or not. lookup is set when the quick_handler is called out of ap_sub_req_lookup_uri()

◆ resume_connection()

void resume_connection	(	conn_rec *	c,
		request_rec *	r
	)

Notification that connection handling is resuming (associating with a thread)

Parameters

c	The current connection
r	The current request, or NULL if there is no active request

See also: ap_hook_suspend_connection

Note: This hook is not implemented by MPMs like Prefork and Worker which handle all processing of a particular connection on the same thread.; This hook will be called on the thread that will resume processing the connection.; This hook is not called at the beginning of connection processing. This hook only notifies a module when processing resumes for a previously-suspended connection.; Resumption and subsequent suspension of a connection solely to perform I/O by the MPM, with no execution of non-MPM code, may not necessarily result in a call to this hook.

◆ ssl_conn_is_ssl()

int ssl_conn_is_ssl ( conn_rec * c )

This hook allows modules that manage SSL connection to register their inquiry function for checking if a connection is using SSL from them.

Parameters

c	The current connection

Returns: OK if the connection is using SSL, DECLINED if not.

◆ ssl_var_lookup()

const char* ssl_var_lookup	(	apr_pool_t *	p,
		server_rec *	s,
		conn_rec *	c,
		request_rec *	r,
		const char *	name
	)

This hook allows modules to look up SSL related variables for a server/connection/request, depending on what they inquire. Some variables will only be available for a connection/request, for example.

Parameters

p	The pool to allocate a returned value in, MUST be provided
s	The server to inquire a value for, maybe NULL
c	The current connection, maybe NULL
r	The current request, maybe NULL
name	The name of the variable to retrieve, MUST be provided

Returns: value or the variable or NULL if not provided/available

◆ suspend_connection()

void suspend_connection	(	conn_rec *	c,
		request_rec *	r
	)

Notification that connection handling is suspending (disassociating from the current thread)

Parameters

c	The current connection
r	The current request, or NULL if there is no active request

See also: ap_hook_resume_connection

Note: This hook is not implemented by MPMs like Prefork and Worker which handle all processing of a particular connection on the same thread.; This hook will be called on the thread that was previously processing the connection.; This hook is not called at the end of connection processing. This hook only notifies a module when processing of an active connection is suspended.; Resumption and subsequent suspension of a connection solely to perform I/O by the MPM, with no execution of non-MPM code, may not necessarily result in a call to this hook.

◆ test_config()

void test_config	(	apr_pool_t *	pconf,
		server_rec *	s
	)

Run the test_config function for each module; this hook is run only if the server was invoked to test the configuration syntax.

Parameters

pconf	The config pool
s	The list of server_recs

Note: To avoid reordering problems due to different buffering, hook functions should only apr_file_*() to print to stdout/stderr and not simple printf()/fprintf().

◆ translate_name()

int translate_name ( request_rec * r )

This hook allow modules an opportunity to translate the URI into an actual filename. If no modules do anything special, the server's default rules will be followed.

Parameters

r	The current request

Returns: OK, DECLINED, or HTTP_...

◆ type_checker()

int type_checker ( request_rec * r )

This routine is called to determine and/or set the various document type information bits, like Content-type (via r->content_type), language, et cetera.

Parameters

r	the current request

Returns: OK, DECLINED, or HTTP_...

Functions

Detailed Description

Function Documentation

◆ access_checker()

◆ access_checker_ex()

◆ auth_checker()

◆ check_config()

◆ check_user_id()

◆ child_init()

◆ child_status()

◆ create_request()

◆ dirwalk_stat()

◆ end_generation()

◆ error_log()

◆ fixups()

◆ force_authn()

◆ generate_log_id()

◆ get_mgmt_items()

◆ handler()

◆ header_parser()

◆ input_pending()

◆ insert_error_filter()

◆ insert_filter()

◆ map_to_storage()

◆ monitor()

◆ mpm()

◆ mpm_get_name()

◆ mpm_query()

◆ mpm_register_poll_callback()

◆ mpm_register_timed_callback()

◆ mpm_resume_suspended()

◆ open_htaccess()

◆ open_logs()

◆ optional_fn_retrieve()

◆ output_pending()

◆ post_config()

◆ post_perdir_config()

◆ pre_config()

◆ pre_mpm()

◆ pre_translate_name()

◆ quick_handler()

◆ resume_connection()

◆ ssl_conn_is_ssl()

◆ ssl_var_lookup()

◆ suspend_connection()

◆ test_config()

◆ translate_name()

◆ type_checker()