include/ap_mpm.h

/* ====================================================================
 * Copyright (c) 1995-1999 The Apache Group.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *    distribution.
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 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the Apache Group
 *    for use in the Apache HTTP server project (http://www.apache.org/)."
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 *    apache@apache.org.
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 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Group and was originally based
 * on public domain software written at the National Center for
 * Supercomputing Applications, University of Illinois, Urbana-Champaign.
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#ifndef AP_MMN_H
#define AP_MMN_H

/* run until a restart/shutdown is indicated, return 1 for shutdown
   0 otherwise */
API_EXPORT(int) ap_mpm_run(pool *pconf, pool *plog, server_rec *server_conf);

/* predicate indicating if a graceful stop has been requested ...
   used by the connection loop */
API_EXPORT(int) ap_mpm_graceful_stop(void);

#ifdef HAS_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

#endif