mpm_common.h revision 346029f34d03eb20d84fc35664426d3874b00f9e
0922cbe8300e97215564748d449824f458196335Lennart Poettering/* ====================================================================
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * The Apache Software License, Version 1.1
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Copyright (c) 2000-2001 The Apache Software Foundation. All rights
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5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * notice, this list of conditions and the following disclaimer.
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5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * ====================================================================
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * This software consists of voluntary contributions made by many
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * individuals on behalf of the Apache Software Foundation. For more
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * information on the Apache Software Foundation, please see
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Portions of this software are based upon public domain software
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * originally written at the National Center for Supercomputing Applications,
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * University of Illinois, Urbana-Champaign.
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering/* The purpose of this file is to store the code that MOST mpm's will need
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * this does not mean a function only goes into this file if every MPM needs
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * it. It means that if a function is needed by more than one MPM, and
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * future maintenance would be served by making the code common, then the
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * function belongs here.
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * This is going in src/main because it is not platform specific, it is
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * specific to multi-process servers, but NOT to Unix. Which is why it
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * does not belong in src/os/unix
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering#include <netinet/tcp.h> /* for TCP_NODELAY */
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering#include "mpm.h" /* for AP_MPM_NEEDS_RECLAIM_CHILD_PROCESSES setting */
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @package Multi-Processing Modules functions
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering/* The maximum length of the queue of pending connections, as defined
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * by listen(2). Under some systems, it should be increased if you
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * are experiencing a heavy TCP SYN flood attack.
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * It defaults to 511 instead of 512 because some systems store it
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * as an 8-bit datatype; 512 truncated to 8-bits is 0, while 511 is
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * 255 when truncated.
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Make sure all child processes that have been spawned by the parent process
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * have died. This includes process registered as "other_children".
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @warning This is only defined if the MPM defines
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * MPM_NEEDS_RECLAIM_CHILD_PROCESS
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @param terminate Either 1 or 0. If 1, send the child processes SIGTERM
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * each time through the loop. If 0, give the process time to die
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * on its own before signalling it.
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @tip This function requires that some macros are defined by the MPM: <pre>
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * MPM_SYNC_CHILD_TABLE -- sync the scoreboard image between child and parent
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * MPM_CHILD_PID -- Get the pid from the specified spot in the scoreboard
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * MPM_NOTE_CHILD_KILLED -- Note the child died in the scoreboard
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poetteringvoid ap_reclaim_child_processes(int terminate);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Determine if any child process has died. If no child process died, then
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * this process sleeps for the amount of time specified by the MPM defined
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * macro SCOREBOARD_MAINTENANCE_INTERVAL.
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @param status The return code if a process has died
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @param ret The process id of the process that died
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @param p The pool to allocate out of
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poetteringvoid ap_wait_or_timeout(apr_wait_t *status, apr_proc_t *ret, apr_pool_t *p);
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * Log why a child died to the error log, if the child died without the
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * parent signalling it.
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @param pid The child that has died
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @param status The status returned from ap_wait_or_timeout
d4205751d4643c272059a3728045929dd0e5e800Lennart Poetteringvoid ap_process_child_status(apr_proc_t *pid, apr_wait_t status);
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering#if defined(TCP_NODELAY) && !defined(MPE) && !defined(TPF)
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * Turn off the nagle algorithm for the specified socket. The nagle algorithm
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * says that we should delay sending partial packets in the hopes of getting
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * more data. There are bad interactions between persistent connections and
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Nagle's algorithm that have severe performance penalties.
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @param s The socket to disable nagle for.
d4205751d4643c272059a3728045929dd0e5e800Lennart Poetteringvoid ap_sock_disable_nagle(apr_socket_t *s);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering#define ap_sock_disable_nagle(s) /* NOOP */
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * Convert a username to a numeric ID
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @param name The name to convert
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @return The user id corresponding to a name
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @deffunc uid_t ap_uname2id(const char *name)
d4205751d4643c272059a3728045929dd0e5e800Lennart PoetteringAP_DECLARE(uid_t) ap_uname2id(const char *name);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Convert a group name to a numeric ID
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @param name The name to convert
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @return The group id corresponding to a name
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @deffunc gid_t ap_gname2id(const char *name)
d4205751d4643c272059a3728045929dd0e5e800Lennart PoetteringAP_DECLARE(gid_t) ap_gname2id(const char *name);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering#define AP_MPM_HARD_LIMITS_FILE APACHE_MPM_DIR "/mpm_default.h"
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Open the pipe-of-death. The pipe of death is used to tell all child
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * processes that it is time to die gracefully.
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @param p The pool to use for allocating the pipe
d4205751d4643c272059a3728045929dd0e5e800Lennart PoetteringAP_DECLARE(apr_status_t) ap_mpm_pod_open(apr_pool_t *p, ap_pod_t **pod);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Check the pipe to determine if the process has been signalled to die.
d4205751d4643c272059a3728045929dd0e5e800Lennart PoetteringAP_DECLARE(apr_status_t) ap_mpm_pod_check(ap_pod_t *pod);
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * Close the pipe-of-death
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart PoetteringAP_DECLARE(apr_status_t) ap_mpm_pod_close(ap_pod_t *pod);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Write data to the pipe-of-death, signalling that one child process
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * @param p The pool to use when allocating any required structures.
d4205751d4643c272059a3728045929dd0e5e800Lennart PoetteringAP_DECLARE(apr_status_t) ap_mpm_pod_signal(ap_pod_t *pod);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering * Write data to the pipe-of-death, signalling that all child process
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @param p The pool to use when allocating any required structures.
d4205751d4643c272059a3728045929dd0e5e800Lennart Poettering * @param num The number of child processes to kill
d4205751d4643c272059a3728045929dd0e5e800Lennart PoetteringAP_DECLARE(void) ap_mpm_pod_killpg(ap_pod_t *pod, int num);
5d6a86d7a034a1fb3d6e3f1b58e2c13739270894Lennart Poettering#endif /* !APACHE_MPM_COMMON_H */