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/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef APACHE_HTTP_MAIN_H
#define APACHE_HTTP_MAIN_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* Routines in http_main.c which other code --- in particular modules ---
* may want to call. Right now, that's limited to timeout handling.
* There are two functions which modules can call to trigger a timeout
* (with the per-virtual-server timeout duration); these are hard_timeout
* and soft_timeout.
*
* The difference between the two is what happens when the timeout
* expires (or earlier than that, if the client connection aborts) ---
* a soft_timeout just puts the connection to the client in an
* "aborted" state, which will cause http_protocol.c to stop trying to
* talk to the client, but otherwise allows the code to continue normally.
* hard_timeout(), by contrast, logs the request, and then aborts it
* completely --- longjmp()ing out to the accept() loop in http_main.
* Any resources tied into the request's resource pool will be cleaned up;
* everything that isn't will leak.
*
* soft_timeout() is recommended as a general rule, because it gives your
* code a chance to clean up. However, hard_timeout() may be the most
* convenient way of dealing with timeouts waiting for some external
* resource other than the client, if you can live with the restrictions.
*
* (When a hard timeout is in scope, critical sections can be guarded
* with block_alarms() and unblock_alarms() --- these are declared in
* alloc.c because they are most often used in conjunction with
* routines to allocate something or other, to make sure that the
* cleanup does get registered before any alarm is allowed to happen
* which might require it to be cleaned up; they * are, however,
* implemented in http_main.c).
*
* NOTE! It's not "fair" for a hard_timeout to be in scope through calls
* across modules. Your module code really has no idea what other modules may
* be present in the server, and they may not take too kindly to having a
* longjmp() happen -- it could result in corrupted state. Heck they may not
* even take to kindly to a soft_timeout()... because it can cause EINTR to
* happen on pretty much any syscall, and unless all the libraries and modules
* in use are known to deal well with EINTR it could cause corruption as well.
* But things are likely to do much better with a soft_timeout in scope than a
* hard_timeout.
*
* A module MAY NOT use a hard_timeout() across * sub_req_lookup_xxx()
* functions, or across run_sub_request() functions. A module SHOULD NOT use a
* soft_timeout() in either of these cases, but sometimes there's just no
* choice.
*
* kill_timeout() will disarm either variety of timeout.
*
* reset_timeout() resets the timeout in progress.
*/
API_EXPORT(void) ap_start_shutdown(void);
API_EXPORT(void) ap_start_restart(int);
API_EXPORT(void) ap_hard_timeout(char *, request_rec *);
API_EXPORT(void) ap_keepalive_timeout(char *, request_rec *);
API_EXPORT(void) ap_soft_timeout(char *, request_rec *);
API_EXPORT(void) ap_kill_timeout(request_rec *);
API_EXPORT(void) ap_reset_timeout(request_rec *);
API_EXPORT(void) ap_child_terminate(request_rec *r);
API_EXPORT(void) ap_sync_scoreboard_image(void);
API_EXPORT(int) ap_update_child_status(int child_num, int status, request_rec *r);
void ap_time_process_request(int child_num, int status);
API_EXPORT(unsigned int) ap_set_callback_and_alarm(void (*fn) (int), int x);
API_EXPORT(int) ap_check_alarm(void);
void setup_signal_names(char *prefix);
/* functions for determination and setting of accept() mutexing */
char *ap_default_mutex_method(void);
char *ap_init_mutex_method(char *t);
#ifndef NO_OTHER_CHILD
/*
* register an other_child -- a child which the main loop keeps track of
* and knows it is different than the rest of the scoreboard.
*
* pid is the pid of the child.
*
* maintenance is a function that is invoked with a reason, the data
* pointer passed here, and when appropriate a status result from waitpid().
*
* write_fd is an fd that is probed for writing by select() if it is ever
* unwritable, then maintenance is invoked with reason OC_REASON_UNWRITABLE.
* This is useful for log pipe children, to know when they've blocked. To
* disable this feature, use -1 for write_fd.
*/
API_EXPORT(void) ap_register_other_child(int pid,
void (*maintenance) (int reason, void *data, ap_wait_t status), void *data,
int write_fd);
#define OC_REASON_DEATH 0 /* child has died, caller must call
* unregister still */
#define OC_REASON_UNWRITABLE 1 /* write_fd is unwritable */
#define OC_REASON_RESTART 2 /* a restart is occuring, perform
* any necessary cleanup (including
* sending a special signal to child)
*/
#define OC_REASON_UNREGISTER 3 /* unregister has been called, do
* whatever is necessary (including
* kill the child) */
#define OC_REASON_LOST 4 /* somehow the child exited without
* us knowing ... buggy os? */
/*
* unregister an other_child. Note that the data pointer is used here, and
* is assumed to be unique per other_child. This is because the pid and
* write_fd are possibly killed off separately.
*/
API_EXPORT(void) ap_unregister_other_child(void *data);
#endif
#ifdef __cplusplus
}
#endif
#endif /* !APACHE_HTTP_MAIN_H */
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