mpm_netware.c revision ca47a2b6bcea23e8af185c68f256dcbbfd2a0f9d
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000-2001 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
*
* Portions of this software are based upon public domain software
* originally written at the National Center for Supercomputing Applications,
* University of Illinois, Urbana-Champaign.
*/
/*
* httpd.c: simple http daemon for answering WWW file requests
*
*
* 03-21-93 Rob McCool wrote original code (up to NCSA HTTPd 1.3)
*
* 03-06-95 blong
* changed server number for child-alone processes to 0 and changed name
* of processes
*
* 03-10-95 blong
* Added numerous speed hacks proposed by Robert S. Thau (rst@ai.mit.edu)
* including set group before fork, and call gettime before to fork
* to set up libraries.
*
* 04-14-95 rst / rh
* Brandon's code snarfed from NCSA 1.4, but tinkered to work with the
* Apache server, and also to have child processes do accept() directly.
*
* April-July '95 rst
* Extensive rework for Apache.
*/
#include "apr.h"
#include "apr_portable.h"
#include "apr_strings.h"
#include "apr_thread_proc.h"
#include "apr_signal.h"
#include "apr_tables.h"
#include "apr_getopt.h"
#include "apr_thread_mutex.h"
#define APR_WANT_STDIO
#define APR_WANT_STRFUNC
#include "apr_want.h"
#include <unistd.h>
#endif
#endif
#define CORE_PRIVATE
#include "ap_config.h"
#include "httpd.h"
#include "mpm_default.h"
#include "http_main.h"
#include "http_log.h"
#include "http_config.h"
#include "http_core.h" /* for get_remote_host */
#include "http_connection.h"
#include "scoreboard.h"
#include "ap_mpm.h"
#include "mpm_common.h"
#include "ap_listen.h"
#include "ap_mmn.h"
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#include <signal.h>
#include <netware.h>
#include <library.h>
/* Limit on the total --- clients will be locked out if more servers than
* this are needed. It is intended solely to keep the server from crashing
* when things get out of hand.
*
* We keep a hard maximum number of servers, for two reasons --- first off,
* in case something goes seriously wrong, we want to stop the fork bomb
* short of actually crashing the machine we're running on by filling some
* kernel table. Secondly, it keeps the size of the scoreboard file small
* enough that we can read the whole thing without worrying too much about
* the overhead.
*/
#ifndef HARD_SERVER_LIMIT
#define HARD_SERVER_LIMIT 1
#endif
/* Limit on the threads per process. Clients will be locked out if more than
* this * HARD_SERVER_LIMIT are needed.
*
* We keep this for one reason it keeps the size of the scoreboard file small
* enough that we can read the whole thing without worrying too much about
* the overhead.
*/
#ifndef HARD_THREAD_LIMIT
#define HARD_THREAD_LIMIT 2048
#endif
#define WORKER_DEAD SERVER_DEAD
#define WORKER_STARTING SERVER_STARTING
#define WORKER_READY SERVER_READY
#define WORKER_IDLE_KILL SERVER_IDLE_KILL
/* config globals */
int ap_threads_per_child=0; /* Worker threads per child */
int ap_thread_stack_size=65536;
static apr_thread_mutex_t *accept_lock;
static int ap_threads_to_start=0;
static int ap_threads_min_free=0;
static int ap_threads_max_free=0;
static int ap_threads_limit=0;
/*
* The max child slot ever assigned, preserved across restarts. Necessary
* to deal with MaxClients changes across SIGWINCH restarts. We use this
* value to optimize routines that have to scan the entire scoreboard.
*/
int ap_max_workers_limit = -1;
/* *Non*-shared http_main globals... */
static apr_socket_t *sd;
static int listenmaxfd;
//static pid_t parent_pid;
static int die_now = 0;
/* Keep track of the number of worker threads currently active */
static int worker_thread_count;
/* Structure used to register/deregister a console handler with the OS */
#define HANDLEDCOMMAND 0
#define NOTMYCOMMAND 1
static int show_settings = 0;
#if 0
#else
#define DBPRINT0(s)
#endif
/* a clean exit from a child with proper cleanup */
{
if (worker_num >=0)
(request_rec *) NULL);
NXThreadExit((void*)&code);
}
{
switch(query_code){
case AP_MPMQ_MAX_DAEMON_USED:
*result = 1;
return APR_SUCCESS;
case AP_MPMQ_IS_THREADED:
return APR_SUCCESS;
case AP_MPMQ_IS_FORKED:
return APR_SUCCESS;
return APR_SUCCESS;
return APR_SUCCESS;
case AP_MPMQ_MAX_THREADS:
return APR_SUCCESS;
*result = 0;
return APR_SUCCESS;
return APR_SUCCESS;
*result = 0;
return APR_SUCCESS;
return APR_SUCCESS;
return APR_SUCCESS;
case AP_MPMQ_MAX_DAEMONS:
*result = 1;
return APR_SUCCESS;
}
return APR_ENOTIMPL;
}
/*****************************************************************
* Connection structures and accounting...
*/
/* volatile just in case */
static int volatile shutdown_pending;
static int volatile restart_pending;
static int volatile is_graceful;
static int volatile wait_to_finish=1;
ap_generation_t volatile ap_my_generation=0;
static void mpm_term(void)
{
wait_to_finish = 0;
}
{
if (shutdown_pending == 1) {
/* Um, is this _probably_ not an error, if the user has
* tried to do a shutdown twice quickly, so we won't
* worry about reporting it.
*/
return;
}
shutdown_pending = 1;
DBPRINT0 ("waiting for threads\n");
while (wait_to_finish) {
}
DBPRINT0 ("goodbye\n");
}
/* restart() is the signal handler for SIGHUP and SIGWINCH
* in the parent process, unless running in ONE_PROCESS mode
*/
static void restart(void)
{
if (restart_pending == 1) {
/* Probably not an error - don't bother reporting it */
return;
}
restart_pending = 1;
is_graceful = 1;
}
static void set_signals(void)
{
}
/*****************************************************************
* Child process main loop.
* The following vars are static to avoid getting clobbered by longjmp();
* they are really private to child_main.
*/
int ap_graceful_stop_signalled(void)
{
/* not ever called anymore... */
return 0;
}
{
int numfds = 0;
numfds++;
}
}
return 0;
}
static void worker_main(void *arg)
{
int sockdes;
int worker_num_arg = (int)arg;
void *sbh;
int my_worker_num = worker_num_arg;
int requests_this_child = 0;
int srv;
}
(request_rec *) NULL);
while (!die_now) {
/*
* (Re)initialize this child to a pre-connection state.
*/
current_conn = NULL;
if ((ap_max_requests_per_child > 0
&& requests_this_child++ >= ap_max_requests_per_child)) {
}
(request_rec *) NULL);
/*
* Wait for an acceptable connection to arrive.
*/
/* Lock around "accept", if necessary */
for (;;) {
if (shutdown_pending || restart_pending || (ap_scoreboard_image->servers[0][my_worker_num].status == WORKER_IDLE_KILL)) {
}
/* more than one socket */
/* Single Unix documents select as returning errnos
* EBADF, EINTR, and EINVAL... and in none of those
* cases does it make sense to continue. In fact
* on Linux 2.0.x we seem to end up with EFAULT
* occasionally, and we'd loop forever due to it.
*/
}
if (srv <= 0)
continue;
/* we remember the last_lr we searched last time around so that
we don't end up starving any particular listening socket */
lr = ap_listeners;
}
else {
if (!lr)
lr = ap_listeners;
}
do {
goto got_listener;
if (!lr)
lr = ap_listeners;
/* FIXME: if we get here, something bad has happened, and we're
probably gonna spin forever.
*/
continue;
/* if we accept() something we don't want to die, so we have to
* defer the exit
*/
for (;;) {
break;
}
if (stat == APR_SUCCESS)
break; /* We have a socket ready for reading */
else {
/* Our old behaviour here was to continue after accept()
* errors. But this leads us into lots of troubles
* because most of the errors are quite fatal. For
* example, EMFILE can be caused by slow descriptor
* leaks (say in a 3rd party module, or libc). It's
* foolish for us to continue after an EMFILE. We also
* seem to tickle kernel bugs on some platforms which
* lead to never-ending loops here. So it seems best
* to just exit in most cases.
*/
switch (stat) {
/* Linux generates the rest of these, other tcp
* stacks (i.e. bsd) tend to hide them behind
* getsockopt() interfaces. They occur when
* the net goes sour or the client disconnects
* after the three-way handshake has been done
* in the kernel but before userland has picked
* up the socket.
*/
case ECONNRESET:
case ETIMEDOUT:
case EHOSTUNREACH:
case ENETUNREACH:
break;
case ENETDOWN:
/*
* When the network layer has been shut down, there
* is not much use in simply exiting: the parent
* would simply re-create us (and we'd fail again).
* Use the CHILDFATAL code to tear the server down.
* @@@ Martin's idea for possible improvement:
* A different approach would be to define
* a new APEXIT_NETDOWN exit code, the reception
* of which would make the parent shutdown all
* children, then idle-loop until it detected that
* the network is up again, and restart the children.
* Ben Hyde noted that temporary ENETDOWN situations
* occur in mobile IP.
*/
"apr_accept: giving up.");
default:
"apr_accept: (client socket)");
}
}
}
/*
* We now have a connection, so set it up with the appropriate
*/
my_worker_num, sbh);
if (current_conn) {
}
}
}
{
int tid;
int err=0;
}
(request_rec *) NULL);
if (ctx = NXContextAlloc((void (*)(void *)) worker_main, (void*)slot, NX_PRIO_MED, ap_thread_stack_size, NX_CTX_NORMAL, &err)) {
char threadName[32];
if (err) {
NXContextFree (ctx);
}
}
if (err) {
/* create thread didn't succeed. Fix the scoreboard or else
* it will say SERVER_STARTING forever and ever
*/
(request_rec *) NULL);
/* In case system resources are maxxed out, we don't want
Apache running away with the CPU trying to fork over and
over and over again. */
return -1;
}
return 0;
}
/* start up a bunch of worker threads */
static void startup_workers(int number_to_start)
{
int i;
for (i = 0; number_to_start && i < ap_threads_limit; ++i) {
continue;
}
if (make_child(ap_server_conf, i) < 0) {
break;
}
}
}
/*
* idle_spawn_rate is the number of children that will be spawned on the
* next maintenance cycle if there aren't enough idle servers. It is
* doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by
* without the need to spawn.
*/
static int idle_spawn_rate = 1;
#ifndef MAX_SPAWN_RATE
#define MAX_SPAWN_RATE (64)
#endif
static int hold_off_on_exponential_spawning;
static void perform_idle_server_maintenance(apr_pool_t *p)
{
int i;
int to_kill;
int idle_count;
int free_length;
int free_slots[MAX_SPAWN_RATE];
int last_non_dead;
int total_non_dead;
/* initialize the free_list */
free_length = 0;
to_kill = -1;
idle_count = 0;
last_non_dead = -1;
total_non_dead = 0;
for (i = 0; i < ap_threads_limit; ++i) {
int status;
break;
if (status == WORKER_DEAD) {
/* try to keep children numbers as low as possible */
if (free_length < idle_spawn_rate) {
free_slots[free_length] = i;
++free_length;
}
}
else if (status == WORKER_IDLE_KILL) {
/* If it is already marked to die, skip it */
continue;
}
else {
/* We consider a starting server as idle because we started it
* at least a cycle ago, and if it still hasn't finished starting
* then we're just going to swamp things worse by forking more.
* So we hopefully won't need to fork more if we count it.
* This depends on the ordering of SERVER_READY and SERVER_STARTING.
*/
if (status <= WORKER_READY) {
++ idle_count;
/* always kill the highest numbered child if we have to...
* no really well thought out reason ... other than observing
* the server behaviour under linux where lower numbered children
* tend to service more hits (and hence are more likely to have
* their data in cpu caches).
*/
to_kill = i;
}
last_non_dead = i;
}
}
if (idle_count > ap_threads_max_free) {
/* kill off one child... we use the pod because that'll cause it to
* shut down gracefully, in case it happened to pick up a request
* while we were counting
*/
idle_spawn_rate = 1;
(request_rec *) NULL);
}
else if (idle_count < ap_threads_min_free) {
/* terminate the free list */
if (free_length == 0) {
/* only report this condition once */
static int reported = 0;
if (!reported) {
"server reached MaxClients setting, consider"
" raising the MaxClients setting");
reported = 1;
}
idle_spawn_rate = 1;
}
else {
if (idle_spawn_rate >= 8) {
"server seems busy, (you may need "
"to increase StartServers, or Min/MaxSpareServers), "
"spawning %d children, there are %d idle, and "
"%d total children", idle_spawn_rate,
}
DBPRINT0("\n");
for (i = 0; i < free_length; ++i) {
}
/* the next time around we want to spawn twice as many if this
* wasn't good enough, but not if we've just done a graceful
*/
}
else if (idle_spawn_rate < MAX_SPAWN_RATE) {
idle_spawn_rate *= 2;
}
}
}
else {
idle_spawn_rate = 1;
}
}
static void display_settings ()
{
for (i=0;i<SERVER_NUM_STATUS;i++) {
status_array[i] = 0;
}
for (i = 0; i < ap_threads_limit; ++i) {
status_array[status]++;
}
for (i=0;i<SERVER_NUM_STATUS;i++) {
switch(i)
{
case SERVER_DEAD:
break;
case SERVER_STARTING:
break;
case SERVER_READY:
break;
case SERVER_BUSY_READ:
break;
case SERVER_BUSY_WRITE:
break;
case SERVER_BUSY_KEEPALIVE:
break;
case SERVER_BUSY_LOG:
break;
case SERVER_BUSY_DNS:
break;
case SERVER_CLOSING:
break;
case SERVER_GRACEFUL:
break;
case SERVER_IDLE_KILL:
break;
default:
break;
}
if (i != SERVER_DEAD)
total+=status_array[i];
}
}
static int setup_listeners(server_rec *s)
{
int sockdes;
if (ap_setup_listeners(s) < 1 ) {
"no listening sockets available, shutting down");
return -1;
}
listenmaxfd = -1;
if (sockdes > listenmaxfd) {
}
}
return 0;
}
/*****************************************************************
* Executive routines.
*/
{
ap_server_conf = s;
if (setup_listeners(s)) {
"no listening sockets available, shutting down");
return -1;
}
restart_pending = shutdown_pending = 0;
worker_thread_count = 0;
if (!is_graceful) {
}
/* Only set slot 0 since that is all NetWare will ever have. */
set_signals();
"%s configured -- resuming normal operations",
"Server built: %s", ap_get_server_built());
while (!restart_pending && !shutdown_pending) {
if (show_settings)
}
if (shutdown_pending) { /* Got an unload from the console */
"caught SIGTERM, shutting down");
DBPRINT0 ("Shutdown pending. Waiting for threads to terminate...\n");
while (worker_thread_count > 0)
return 1;
}
else { /* the only other way out is a restart */
/* 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.
*/
"Graceful restart requested, doing restart");
/* Wait for all of the threads to terminate before initiating the restart */
DBPRINT0 ("Restart pending. Waiting for threads to terminate...\n");
while (worker_thread_count > 0) {
}
DBPRINT0 ("restarting...\n");
}
return 0;
}
{
int debug;
is_graceful = 0;
ap_extended_status = 0;
}
static void netware_mpm_hooks(apr_pool_t *p)
{
}
{
char *def_server_root;
char optbuf[3];
const char *opt_arg;
/* Rewrite process->argv[];
*
* add default -d serverroot from the path of this executable
*
* The end result will look like:
* The -d serverroot default from the running executable
*/
if (s) {
for (i=len; i; i--) {
if (s[i] == '\\' || s[i] == '/') {
s[i] = NULL;
break;
}
}
/* Use process->pool so that the rewritten argv
* lasts for the lifetime of the server process,
* because pconf will be destroyed after the
* initial pre-flight of the config parser.
*/
sizeof(const char *));
optbuf[0] = '-';
switch (optbuf[1]) {
default:
*(const char **)apr_array_push(mpm_new_argv) =
if (opt_arg) {
}
break;
}
}
}
}
}
{
/* All added commands begin with "HTTPD " */
printf("Restart Requested...\n");
restart();
}
}
}
}
printf("Shutdown Requested...\n");
shutdown_pending = 1;
}
if (show_settings) {
show_settings = 0;
}
else {
show_settings = 1;
}
}
else {
}
/* Tell NetWare we handled the command */
return HANDLEDCOMMAND;
}
/* Tell NetWare that the command isn't mine */
return NOTMYCOMMAND;
}
static int InstallConsoleHandler(void)
{
/* Our command line handler interfaces the system operator
with this NLM */
if (!ConsoleHandler.rTag)
{
printf("Error on allocate resource tag\n");
return 1;
}
/* The Remove procedure unregisters the console handler */
return 0;
}
static void RemoveConsoleHandler(void)
{
}
{
return err;
}
return NULL;
}
{
return err;
}
if (ap_threads_min_free <= 0) {
"WARNING: detected MinSpareServers set to non-positive.");
"Resetting to 1 to avoid almost certain Apache failure.");
"Please read the documentation.");
ap_threads_min_free = 1;
}
return NULL;
}
{
return err;
}
return NULL;
}
{
return err;
}
if (ap_threads_limit > HARD_THREAD_LIMIT) {
"WARNING: MaxClients of %d exceeds compile time limit "
" lowering MaxClients to %d. To increase, please "
"see the", HARD_SERVER_LIMIT);
" HARD_SERVER_LIMIT define in %s.",
}
else if (ap_threads_limit < 1) {
"WARNING: Require MaxClients > 0, setting to 1");
ap_threads_limit = 1;
}
return NULL;
}
const char *arg)
{
return err;
}
return NULL;
}
static const command_rec netware_mpm_cmds[] = {
"Stack size each created thread will use."),
"Number of worker threads launched at server startup"),
"Minimum number of idle threads, to handle request spikes"),
"Maximum number of idle threads"),
"Maximum number of worker threads alive at the same time"),
{ NULL }
};
netware_rewrite_args, /* 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 */
netware_mpm_cmds, /* command apr_table_t */
netware_mpm_hooks, /* register hooks */
};