spmt_os2.c

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

	idle_spawn_rate = 1;
    }
}

AP_DECLARE(apr_status_t) ap_mpm_query(int query_code, int *result)
{
    switch(query_code){
        case AP_MPMQ_MAX_DAEMONS:
            *result = max_daemons_limit;
            return APR_SUCCESS;
        case AP_MPMQ_IS_THREADED:
            *result = 1;
            return APR_SUCCESS;
        case AP_MPMQ_IS_FORKED:
            *result = 0;
            return APR_SUCCESS;
    }
    return APR_ENOTIMPL;
} 

/*****************************************************************
 * Executive routines.
 */

int ap_mpm_run(apr_pool_t *_pconf, apr_pool_t *plog, server_rec *s)
{
    int remaining_children_to_start;
    int i;
    apr_status_t status;

    pconf = _pconf;
    ap_server_conf = s;
    ap_log_pid(pconf, ap_pid_fname);

    if ((status = ap_listen_open(s->process, s->port)) != APR_SUCCESS) {
	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ALERT, status, s,
		    "no listening sockets available, shutting down");
	return -1;
    }

    SAFE_ACCEPT(accept_mutex_init(pconf));

    if (!is_graceful) {
        ap_create_scoreboard(pconf, SB_NOT_SHARED);
        memset(thread_control, 0, sizeof(thread_control));
    }

    set_signals();

    if (ppthread_globals == NULL) {
        if (DosAllocThreadLocalMemory(1, (PULONG *)&ppthread_globals)) {
            ap_log_error(APLOG_MARK, APLOG_ALERT|APLOG_NOERRNO, 0, ap_server_conf,
                         "Error allocating thread local storage"
                         "Apache is exiting!");
        } else {
          *ppthread_globals = (struct thread_globals *)apr_palloc(pconf, sizeof(struct thread_globals));
        }
    }

    if (ap_daemons_max_free < ap_daemons_min_free + 1)	/* Don't thrash... */
	ap_daemons_max_free = ap_daemons_min_free + 1;

    /* If we're doing a graceful_restart then we're going to see a lot
	* of children exiting immediately when we get into the main loop
	* below (because we just sent them SIGUSR1).  This happens pretty
	* rapidly... and for each one that exits we'll start a new one until
	* we reach at least daemons_min_free.  But we may be permitted to
	* start more than that, so we'll just keep track of how many we're
	* supposed to start up without the 1 second penalty between each fork.
	*/
    remaining_children_to_start = ap_daemons_to_start;
    if (remaining_children_to_start > ap_daemons_limit) {
	remaining_children_to_start = ap_daemons_limit;
    }
    if (!is_graceful) {
	startup_children(remaining_children_to_start);
	remaining_children_to_start = 0;
    }
    else {
	/* give the system some time to recover before kicking into
	    * exponential mode */
	hold_off_on_exponential_spawning = 10;
    }

    ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
		"%s configured -- resuming normal operations",
		ap_get_server_version());
    ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0, ap_server_conf,
		"Server built: %s", ap_get_server_built());
    restart_pending = shutdown_pending = 0;

    printf("%s \n", ap_get_server_version());

    while (!restart_pending && !shutdown_pending) {
	int thread_slot;
	apr_wait_t status;
	int tid = wait_or_timeout(&status);

	/* XXX: if it takes longer than 1 second for all our children
	 * to start up and get into IDLE state then we may spawn an
	 * extra child
	 */
	if (tid >= 0) {
            apr_proc_t dummyproc;
            dummyproc.pid = tid;
            ap_process_child_status(&dummyproc, status);
	    /* non-fatal death... note that it's gone in the scoreboard. */
	    thread_slot = find_thread_by_tid(tid);
	    if (thread_slot >= 0) {
		(void) ap_update_child_status(0, thread_slot, SERVER_DEAD,
					    (request_rec *) NULL);
		if (remaining_children_to_start
		    && thread_slot < ap_daemons_limit) {
		    /* we're still doing a 1-for-1 replacement of dead
			* children with new children
			*/
		    make_child(ap_server_conf, thread_slot);
		    --remaining_children_to_start;
		}
#if APR_HAS_OTHER_CHILD
/* TODO: this won't work, we waited on a thread not a process
	    }
	    else if (reap_other_child(pid, status) == 0) {
*/
#endif
	    }
	    else if (is_graceful) {
		/* Great, we've probably just lost a slot in the
		    * scoreboard.  Somehow we don't know about this
		    * child.
		    */
		ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, ap_server_conf,
			    "long lost child came home! (tid %d)", tid);
	    }
	    /* Don't perform idle maintenance when a child dies,
		* only do it when there's a timeout.  Remember only a
		* finite number of children can die, and it's pretty
		* pathological for a lot to die suddenly.
		*/
	    continue;
	}
	else if (remaining_children_to_start) {
	    /* we hit a 1 second timeout in which none of the previous
		* generation of children needed to be reaped... so assume
		* they're all done, and pick up the slack if any is left.
		*/
	    startup_children(remaining_children_to_start);
	    remaining_children_to_start = 0;
	    /* In any event we really shouldn't do the code below because
		* few of the servers we just started are in the IDLE state
		* yet, so we'd mistakenly create an extra server.
		*/
	    continue;
	}

	perform_idle_server_maintenance();
    }

    if (shutdown_pending) {
	/* Time to gracefully shut down */
        const char *pidfile = NULL;
        int slot;
        TID tid;
        ULONG rc;
        ap_listen_rec *lr;

        for (lr = ap_listeners; lr; lr = lr->next) {
            apr_socket_close(lr->sd);
            DosSleep(0);
        }

        /* Kill off running threads */
        for (slot=0; slot<max_daemons_limit; slot++) {
            if (ap_scoreboard_image->servers[0][slot].status != SERVER_DEAD) {
                tid = ap_scoreboard_image->servers[0][slot].tid;
                rc = DosKillThread(tid);

                if (rc != ERROR_INVALID_THREADID) { // Already dead, ignore
                    if (rc == 0) {
                        rc = DosWaitThread(&tid, DCWW_WAIT);

                        if (rc) {
                            ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, ap_server_conf,
                                         "error %lu waiting for thread to terminate", rc);
                        }
                    } else {
                        ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, ap_server_conf,
                                     "error %lu killing thread", rc);
                    }
                }
            }
        }

        /* cleanup pid file on normal shutdown */
        pidfile = ap_server_root_relative (pconf, ap_pid_fname);
        if ( pidfile != NULL && unlink(pidfile) == 0)
            ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0,
                            ap_server_conf,
                            "removed PID file %s (pid=%ld)",
                            pidfile, (long)getpid());

	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
		    "caught SIGTERM, shutting down");
	return 1;
    }

    /* we've been told to restart */
    signal(SIGHUP, SIG_IGN);
    signal(SIGUSR1, SIG_IGN);

    if (one_process) {
	/* not worth thinking about */
	return 1;
    }

    /* advance to the next generation */
    /* XXX: we really need to make sure this new generation number isn't in
     * use by any of the children.
     */
    ++ap_scoreboard_image->global.running_generation;

    if (is_graceful) {
	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
		    "SIGUSR1 received.  Doing graceful restart");

        /* kill off the idle ones */
        for (i = 0; i < ap_daemons_limit; ++i) {
            thread_control[i].deferred_die = 1;
        }

	/* This is mostly for debugging... so that we know what is still
	    * gracefully dealing with existing request.  But we can't really
	    * do it if we're in a SCOREBOARD_FILE because it'll cause
	    * corruption too easily.
	    */
	for (i = 0; i < ap_daemons_limit; ++i) {
	    if (ap_scoreboard_image->servers[0][i].status != SERVER_DEAD) {
		ap_scoreboard_image->servers[0][i].status = SERVER_GRACEFUL;
	    }
	}
    }
    else {
	/* Kill 'em off */
        for (i = 0; i < ap_daemons_limit; ++i) {
            DosKillThread(ap_scoreboard_image->servers[0][i].tid);
        }
	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
                     "SIGHUP received.  Attempting to restart");
    }

    return 0;
}

static void spmt_os2_pre_config(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptemp)
{
    one_process = !!ap_exists_config_define("ONE_PROCESS");

    is_graceful = 0;
    ap_listen_pre_config();
    ap_daemons_to_start = DEFAULT_START_DAEMON;
    ap_daemons_min_free = DEFAULT_MIN_FREE_DAEMON;
    ap_daemons_max_free = DEFAULT_MAX_FREE_DAEMON;
    ap_daemons_limit = HARD_THREAD_LIMIT;
    ap_pid_fname = DEFAULT_PIDLOG;
    ap_max_requests_per_child = DEFAULT_MAX_REQUESTS_PER_CHILD;
    ap_extended_status = 0;
    ap_scoreboard_fname = NULL;

    apr_cpystrn(ap_coredump_dir, ap_server_root, sizeof(ap_coredump_dir));
}

static void spmt_os2_hooks(apr_pool_t *p)
{
    /* TODO: set one_process properly */ one_process = 0;

    ap_hook_pre_config(spmt_os2_pre_config, NULL, NULL, APR_HOOK_MIDDLE);
}

static const char *set_pidfile(cmd_parms *cmd, void *dummy, char *arg) 
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    if (cmd->server->is_virtual) {
	return "PidFile directive not allowed in <VirtualHost>";
    }
    ap_pid_fname = arg;
    return NULL;
}

static const char *set_daemons_to_start(cmd_parms *cmd, void *dummy, char *arg)
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    ap_daemons_to_start = atoi(arg);
    return NULL;
}

static const char *set_min_free_servers(cmd_parms *cmd, void *dummy, char *arg)
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    ap_daemons_min_free = atoi(arg);
    if (ap_daemons_min_free <= 0) {
       ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, 
                    "WARNING: detected MinSpareServers set to non-positive.");
       ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, 
                    "Resetting to 1 to avoid almost certain Apache failure.");
       ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, 
                    "Please read the documentation.");
       ap_daemons_min_free = 1;
    }
       
    return NULL;
}

static const char *set_max_free_servers(cmd_parms *cmd, void *dummy, char *arg)
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    ap_daemons_max_free = atoi(arg);
    return NULL;
}

static const char *set_server_limit (cmd_parms *cmd, void *dummy, char *arg) 
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    ap_daemons_limit = atoi(arg);
    if (ap_daemons_limit > HARD_THREAD_LIMIT) {
       ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, 
                    "WARNING: MaxClients of %d exceeds compile time limit "
                    "of %d servers,", ap_daemons_limit, HARD_THREAD_LIMIT);
       ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, 
                    " lowering MaxClients to %d.  To increase, please "
                    "see the", HARD_THREAD_LIMIT);
       ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, 
                    " HARD_THREAD_LIMIT define in %s.",
                    AP_MPM_HARD_LIMITS_FILE);
       ap_daemons_limit = HARD_THREAD_LIMIT;
    } 
    else if (ap_daemons_limit < 1) {
	ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, 
                     "WARNING: Require MaxClients > 0, setting to 1");
	ap_daemons_limit = 1;
    }
    return NULL;
}

static const char *set_max_requests(cmd_parms *cmd, void *dummy, char *arg) 
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    ap_max_requests_per_child = atoi(arg);

    return NULL;
}

static const char *set_coredumpdir (cmd_parms *cmd, void *dummy, char *arg) 
{
    apr_finfo_t finfo;
    const char *fname;
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    fname = ap_server_root_relative(cmd->pool, arg);
    if ((apr_stat(&finfo, fname, APR_FINFO_TYPE, cmd->pool) != APR_SUCCESS) 
        || (finfo.filetype != APR_DIR)) {
	return apr_pstrcat(cmd->pool, "CoreDumpDirectory ", fname, 
			  " does not exist or is not a directory", NULL);
    }
    apr_cpystrn(ap_coredump_dir, fname, sizeof(ap_coredump_dir));
    return NULL;
}

/* Stub functions until this MPM supports the connection status API */

AP_DECLARE(void) ap_update_connection_status(long conn_id, const char *key, \
                                             const char *value)
{
    /* NOP */
}

AP_DECLARE(void) ap_reset_connection_status(long conn_id)
{
    /* NOP */
}

static const command_rec spmt_os2_cmds[] = {
LISTEN_COMMANDS
{ "PidFile", set_pidfile, NULL, RSRC_CONF, TAKE1,
    "A file for logging the server process ID"},
{ "StartServers", set_daemons_to_start, NULL, RSRC_CONF, TAKE1,
  "Number of child processes launched at server startup" },
{ "MinSpareServers", set_min_free_servers, NULL, RSRC_CONF, TAKE1,
  "Minimum number of idle children, to handle request spikes" },
{ "MaxSpareServers", set_max_free_servers, NULL, RSRC_CONF, TAKE1,
  "Maximum number of idle children" },
{ "MaxClients", set_server_limit, NULL, RSRC_CONF, TAKE1,
  "Maximum number of children alive at the same time" },
{ "MaxRequestsPerChild", set_max_requests, NULL, RSRC_CONF, TAKE1,
  "Maximum number of requests a particular child serves before dying." },
{ "CoreDumpDirectory", set_coredumpdir, NULL, RSRC_CONF, TAKE1,
  "The location of the directory Apache changes to before dumping core" },
{ NULL }
};

module AP_MODULE_DECLARE_DATA mpm_spmt_os2_module = {
    MPM20_MODULE_STUFF,
    NULL,                       /* hook to run before apache parses args */
    NULL,			/* create per-directory config structure */
    NULL,			/* merge per-directory config structures */
    NULL,			/* create per-server config structure */
    NULL,			/* merge per-server config structures */
    spmt_os2_cmds,		/* command apr_table_t */
    spmt_os2_hooks,		/* register_hooks */
};