path: root/include/http_request.h

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#ifndef APACHE_HTTP_REQUEST_H
#define APACHE_HTTP_REQUEST_H

#include "apr_hooks.h"
#include "util_filter.h"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @file http_request.h
 * @brief Apache Request library
 */

/* http_request.c is the code which handles the main line of request
 * processing, once a request has been read in (finding the right per-
 * directory configuration, building it if necessary, and calling all
 * the module dispatch functions in the right order).
 *
 * The pieces here which are public to the modules, allow them to learn
 * how the server would handle some other file or URI, or perhaps even
 * direct the server to serve that other file instead of the one the
 * client requested directly.
 *
 * There are two ways to do that.  The first is the sub_request mechanism,
 * which handles looking up files and URIs as adjuncts to some other
 * request (e.g., directory entries for multiviews and directory listings);
 * the lookup functions stop short of actually running the request, but
 * (e.g., for includes), a module may call for the request to be run
 * by calling run_sub_req.  The space allocated to create sub_reqs can be
 * reclaimed by calling destroy_sub_req --- be sure to copy anything you care
 * about which was allocated in its apr_pool_t elsewhere before doing this.
 */

/**
 * Create a sub request from the given URI.  This sub request can be
 * inspected to find information about the requested URI
 * @param new_file The URI to lookup
 * @param r The current request
 * @param next_filter The first filter the sub_request should use.  If this is
 *                    NULL, it defaults to the first filter for the main request
 * @return The new request record
 * @deffunc request_rec * ap_sub_req_lookup_uri(const char *new_file, const request_rec *r)
 */
AP_DECLARE(request_rec *) ap_sub_req_lookup_uri(const char *new_file,
                                                const request_rec *r,
                                                ap_filter_t *next_filter);

/**
 * Create a sub request for the given file.  This sub request can be
 * inspected to find information about the requested file
 * @param new_file The URI to lookup
 * @param r The current request
 * @param next_filter The first filter the sub_request should use.  If this is
 *                    NULL, it defaults to the first filter for the main request
 * @return The new request record
 * @deffunc request_rec * ap_sub_req_lookup_file(const char *new_file, const request_rec *r)
 */
AP_DECLARE(request_rec *) ap_sub_req_lookup_file(const char *new_file,
                                              const request_rec *r,
                                              ap_filter_t *next_filter);
/**
 * Create a sub request for the given apr_dir_read result.  This sub request 
 * can be inspected to find information about the requested file
 * @param finfo The apr_dir_read result to lookup
 * @param r The current request
 * @param next_filter The first filter the sub_request should use.  If this is
 *                    NULL, it defaults to the first filter for the main request
 * @return The new request record
 * @deffunc request_rec * ap_sub_req_lookup_dirent(apr_finfo_t *finfo, const request_rec *r)
 * @tip The apr_dir_read flags value APR_FINFO_MIN|APR_FINFO_NAME flag is the 
 * minimum recommended query if the results will be passed to apr_dir_read.
 * The file info passed must include the name, and must have the same relative
 * directory as the current request.
 */
AP_DECLARE(request_rec *) ap_sub_req_lookup_dirent(const apr_finfo_t *finfo,
                                              const request_rec *r,
                                              ap_filter_t *next_filter);
/**
 * Create a sub request for the given URI using a specific method.  This
 * sub request can be inspected to find information about the requested URI
 * @param method The method to use in the new sub request
 * @param new_file The URI to lookup
 * @param r The current request
 * @param next_filter The first filter the sub_request should use.  If this is
 *                    NULL, it defaults to the first filter for the main request
 * @return The new request record
 * @deffunc request_rec * ap_sub_req_method_uri(const char *method, const char *new_file, const request_rec *r)
 */
AP_DECLARE(request_rec *) ap_sub_req_method_uri(const char *method,
                                                const char *new_file,
                                                const request_rec *r,
                                                ap_filter_t *next_filter);
/**
 * An output filter to strip EOS buckets from sub-requests.  This always
 * has to be inserted at the end of a sub-requests filter stack.
 * @param f The current filter
 * @param bb The brigade to filter
 * @deffunc apr_status_t ap_sub_req_output_filter(ap_filter_t *f, apr_bucket_brigade *bb)
 */
AP_CORE_DECLARE_NONSTD(apr_status_t) ap_sub_req_output_filter(ap_filter_t *f,
                                                        apr_bucket_brigade *bb);

/**
 * Run the handler for the sub request
 * @param r The sub request to run
 * @return The return code for the sub request
 * @deffunc int ap_run_sub_req(request_rec *r)
 */
AP_DECLARE(int) ap_run_sub_req(request_rec *r);

/**
 * Free the memory associated with a sub request
 * @param r The sub request to finish
 * @deffunc void ap_destroy_sub_req(request_rec *r)
 */
AP_DECLARE(void) ap_destroy_sub_req(request_rec *r);

/*
 * Then there's the case that you want some other request to be served
 * as the top-level request INSTEAD of what the client requested directly.
 * If so, call this from a handler, and then immediately return OK.
 */

/**
 * Redirect the current request to some other uri
 * @param new_uri The URI to replace the current request with
 * @param r The current request
 * @deffunc void ap_internal_redirect(const char *new_uri, request_rec *r)
 */
AP_DECLARE(void) ap_internal_redirect(const char *new_uri, request_rec *r);

/**
 * This function is designed for things like actions or CGI scripts, when
 * using AddHandler, and you want to preserve the content type across
 * an internal redirect.
 * @param new_uri The URI to replace the current request with.
 * @param r The current request
 * @deffunc void ap_internal_redirect_handler(const char *new_uri, request_rec *r)
 */
AP_DECLARE(void) ap_internal_redirect_handler(const char *new_uri, request_rec *r);

/**
 * Can be used within any handler to determine if any authentication
 * is required for the current request
 * @param r The current request
 * @return 1 if authentication is required, 0 otherwise
 * @deffunc int ap_some_auth_required(request_rec *r)
 */
AP_DECLARE(int) ap_some_auth_required(request_rec *r);
 
/**
 * Determine if the current request is the main request or a sub requests
 * @param r The current request
 * @retrn 1 if this is a main request, 0 otherwise
 * @deffunc int ap_is_initial_req(request_rec *r)
 */
AP_DECLARE(int) ap_is_initial_req(request_rec *r);

/**
 * Function to set the r->mtime field to the specified value if it's later
 * than what's already there.
 * @param r The current request
 * @param dependency_time Time to set the mtime to
 * @deffunc void ap_update_mtime(request_rec *r, apr_time_t dependency_mtime)
 */
AP_DECLARE(void) ap_update_mtime(request_rec *r, apr_time_t dependency_mtime);

/**
 * Add one or more methods to the list permitted to access the resource.
 * Usually executed by the content handler before the response header is
 * sent, but sometimes invoked at an earlier phase if a module knows it
 * can set the list authoritatively.  Note that the methods are ADDED
 * to any already permitted unless the reset flag is non-zero.  The
 * list is used to generate the Allow response header field when it
 * is needed.
 * @param   r     The pointer to the request identifying the resource.
 * @param   reset Boolean flag indicating whether this list should
 *                completely replace any current settings.
 * @param   ...   A NULL-terminated list of strings, each identifying a
 *                method name to add.
 * @return  None.
 * @deffunc void ap_allow_methods(request_rec *r, int reset, ...)
 */
AP_DECLARE(void) ap_allow_methods(request_rec *r, int reset, ...);

#define MERGE_ALLOW 0
#define REPLACE_ALLOW 1

#ifdef CORE_PRIVATE
/* Function called by main.c to handle first-level request */
void ap_process_request(request_rec *);
/**
 * Kill the current request
 * @param type Why the request is dieing
 * @param r The current request
 * @deffunc void ap_die(int type, request_rec *r)
 */
AP_DECLARE(void) ap_die(int type, request_rec *r);
#endif

/* Hooks */

/* XXX: doxygen grouping doesn't appear to work, but it should. Checking with
 * doxygen (Ben).
 */

/**
 * Gives modules a chance to create their request_config entry when the
 * request is created.
 * @param r The current request
 * @ingroup hooks
 */
AP_DECLARE_HOOK(int,create_request,(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.
 * @param r The current request
 * @return OK, DECLINED, or HTTP_...
 * @ingroup hooks
 */
AP_DECLARE_HOOK(int,translate_name,(request_rec *r))

/**
 * This hook allows modules to check the authentication information sent with
 * the request.
 * @param r The current request
 * @return OK, DECLINED, or HTTP_...
 * @ingroup hooks
 */
AP_DECLARE_HOOK(int,check_user_id,(request_rec *r))

/**
 * Allows modules to perform module-specific fixing of header fields.  This
 * is invoked just before any content-handler
 * @param r The current request
 * @return OK, DECLINED, or HTTP_...
 * @ingroup hooks
 */
AP_DECLARE_HOOK(int,fixups,(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.
 * @param r the current request
 * @return OK, DECLINED, or HTTP_...
 * @ingroup hooks
 */
AP_DECLARE_HOOK(int,type_checker,(request_rec *r))

/**
 * This routine is called to check for any module-specific restrictions placed
 * upon the requested resource.
 * @param r the current request
 * @return OK, DECLINED, or HTTP_...
 * @ingroup hooks
 */
AP_DECLARE_HOOK(int,access_checker,(request_rec *r))

/**
 * This routine is called to check to see if the resource being requested
 * requires authorisation.
 * @param r the current request
 * @return OK, DECLINED, or HTTP_...
 * @ingroup hooks
 */
AP_DECLARE_HOOK(int,auth_checker,(request_rec *r))

/**
 * This hook allows modules to insert filters for the current request
 * @param r the current request
 * @ingroup hooks
 */
AP_DECLARE_HOOK(void,insert_filter,(request_rec *r))

AP_DECLARE(int) directory_walk(request_rec *r);
AP_DECLARE(int) location_walk(request_rec *r);
AP_DECLARE(int) file_walk(request_rec *r);

#ifdef __cplusplus
}
#endif

#endif	/* !APACHE_HTTP_REQUEST_H */