beos.c

Apache 2.0.63 is the current stable version of the 2.0 series, and is recommended over any previous

/* 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.
 */

/* The new BeOS MPM!
 *
 * This one basically is a single process multi threaded model, but 
 * I couldn't be bothered adding the spmt_ to the front of the name!
 * Anyway, this is still under development so it isn't yet the default
 * choice.
 */
 
#define CORE_PRIVATE 
 
#include <kernel/OS.h>
#include <unistd.h>
#include <sys/socket.h>
#include <signal.h>

#include "apr_strings.h"
#include "apr_portable.h"
#include "httpd.h" 
#include "http_main.h" 
#include "http_log.h" 
#include "http_config.h"	/* for read_config */ 
#include "http_core.h"		/* for get_remote_host */ 
#include "http_connection.h"
#include "ap_mpm.h"
#include "beosd.h"
#include "ap_listen.h"
#include "scoreboard.h" 
#include "mpm_common.h"
#include "mpm.h"
#include "mpm_default.h"
#include "apr_thread_mutex.h"
#include "apr_poll.h"

extern int _kset_fd_limit_(int num);

/* 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:
 * 1) in case something goes seriously wrong, we want to stop the server starting
 *    threads ad infinitum and crashing the server (remember that BeOS has a 192
 *    thread per team limit).
 * 2) it keeps the size of the scoreboard file small
 *    enough that we can read the whole thing without worrying too much about
 *    the overhead.
 */

/* we only ever have 1 main process running... */ 
#define HARD_SERVER_LIMIT 1

/* 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.
 */
#ifdef NO_THREADS
#define HARD_THREAD_LIMIT 1
#endif
#ifndef HARD_THREAD_LIMIT
#define HARD_THREAD_LIMIT 50 
#endif

/*
 * Actual definitions of config globals
 */

static int ap_threads_to_start=0;
static int ap_max_requests_per_thread = 0;
static int min_spare_threads=0;
static int max_spare_threads=0;
static int ap_thread_limit=0;
static int num_listening_sockets = 0;
static apr_socket_t ** listening_sockets;
apr_thread_mutex_t *accept_mutex = NULL;

static apr_pool_t *pconf;		/* Pool for config stuff */
static apr_pool_t *pchild;		/* Pool for httpd child stuff */

static int server_pid; 
static int mpm_state = AP_MPMQ_STARTING;

/* Keep track of the number of worker threads currently active */
static int worker_thread_count;
apr_thread_mutex_t *worker_thread_count_mutex;

/* The structure used to pass unique initialization info to each thread */
typedef struct {
    int slot;
    apr_pool_t *tpool;
} proc_info;

static void check_restart(void *data);

/*
 * The max child slot ever assigned, preserved across restarts.  Necessary
 * to deal with MaxClients changes across AP_SIG_GRACEFUL restarts.  We use 
 * this value to optimize routines that have to scan the entire scoreboard.
 */
int ap_max_child_assigned = -1;
int ap_max_threads_limit = -1;

static apr_socket_t *udp_sock;
static apr_sockaddr_t *udp_sa;

/* shared http_main globals... */

server_rec *ap_server_conf;

/* one_process */
static int one_process = 0;

#ifdef DEBUG_SIGSTOP
int raise_sigstop_flags;
#endif

/* a clean exit from a child with proper cleanup 
   static void clean_child_exit(int code) __attribute__ ((noreturn)); */
static void clean_child_exit(int code)
{
    if (pchild)
        apr_pool_destroy(pchild);
    exit(code);
}

/* handle all varieties of core dumping signals */
static void sig_coredump(int sig)
{
    chdir(ap_coredump_dir);
    signal(sig, SIG_DFL);
    kill(server_pid, sig);
    /* At this point we've got sig blocked, because we're still inside
     * the signal handler.  When we leave the signal handler it will
     * be unblocked, and we'll take the signal... and coredump or whatever
     * is appropriate for this particular Unix.  In addition the parent
     * will see the real signal we received -- whereas if we called
     * abort() here, the parent would only see SIGABRT.
     */
}

/*****************************************************************
 * 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 child_fatal;
ap_generation_t volatile ap_my_generation = 0;

/*
 * ap_start_shutdown() and ap_start_restart(), below, are a first stab at
 * functions to initiate shutdown or restart without relying on signals. 
 * Previously this was initiated in sig_term() and restart() signal handlers, 
 * but we want to be able to start a shutdown/restart from other sources --
 * e.g. on Win32, from the service manager. Now the service manager can
 * call ap_start_shutdown() or ap_start_restart() as appropiate.  Note that
 * these functions can also be called by the child processes, since global
 * variables are no longer used to pass on the required action to the parent.
 *
 * These should only be called from the parent process itself, since the
 * parent process will use the shutdown_pending and restart_pending variables
 * to determine whether to shutdown or restart. The child process should
 * call signal_parent() directly to tell the parent to die -- this will
 * cause neither of those variable to be set, which the parent will
 * assume means something serious is wrong (which it will be, for the
 * child to force an exit) and so do an exit anyway.
 */

static void ap_start_shutdown(void)
{
    mpm_state = AP_MPMQ_STOPPING;
 
    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;
}

/* do a graceful restart if graceful == 1 */
static void ap_start_restart(int graceful)
{
    mpm_state = AP_MPMQ_STOPPING;

    if (restart_pending == 1) {
        /* Probably not an error - don't bother reporting it */
        return;
    }
    restart_pending = 1;
    is_graceful = graceful;
}

static void sig_term(int sig)
{
    ap_start_shutdown();
}

static void restart(int sig)
{
    ap_start_restart(sig == AP_SIG_GRACEFUL);
}

static void tell_workers_to_exit(void)
{
    apr_size_t len;
    int i = 0;

    mpm_state = AP_MPMQ_STOPPING;

    for (i = 0 ; i < ap_max_child_assigned; i++){
        len = 4;
        if (apr_sendto(udp_sock, udp_sa, 0, "die!", &len) != APR_SUCCESS)
            break;
    }   
}

static void set_signals(void)
{
    struct sigaction sa;

    sigemptyset(&sa.sa_mask);
    sa.sa_flags = 0;

    if (!one_process) {
	sa.sa_handler = sig_coredump;

	if (sigaction(SIGSEGV, &sa, NULL) < 0)
	    ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGSEGV)");
	if (sigaction(SIGBUS, &sa, NULL) < 0)
	    ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGBUS)");
	if (sigaction(SIGABRT, &sa, NULL) < 0)
	    ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGABRT)");
	if (sigaction(SIGILL, &sa, NULL) < 0)
	    ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGILL)");
	sa.sa_flags = 0;
    }
    sa.sa_handler = sig_term;
    if (sigaction(SIGTERM, &sa, NULL) < 0)
	    ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGTERM)");
    if (sigaction(SIGINT, &sa, NULL) < 0)
        ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGINT)");
    
    sa.sa_handler = SIG_IGN;
    if (sigaction(SIGPIPE, &sa, NULL) < 0)
    	ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGPIPE)");

    /* we want to ignore HUPs and AP_SIG_GRACEFUL while we're busy 
     * processing one */
    sigaddset(&sa.sa_mask, SIGHUP);
    sigaddset(&sa.sa_mask, AP_SIG_GRACEFUL);
    sa.sa_handler = restart;
    if (sigaction(SIGHUP, &sa, NULL) < 0)
    	ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGHUP)");
    if (sigaction(AP_SIG_GRACEFUL, &sa, NULL) < 0)
	    ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(" AP_SIG_GRACEFUL_STRING ")");
}

/*****************************************************************
 * Here follows a long bunch of generic server bookkeeping stuff...
 */

int ap_graceful_stop_signalled(void)
{
    /* XXX - Does this really work? - Manoj */
    return is_graceful;
}

/*****************************************************************
 * Child process main loop.
 */

static void process_socket(apr_pool_t *p, apr_socket_t *sock,
                           int my_child_num, apr_bucket_alloc_t *bucket_alloc)
{
    conn_rec *current_conn;
    long conn_id = my_child_num;
    int csd;
    ap_sb_handle_t *sbh;

    (void)apr_os_sock_get(&csd, sock);
    
    if (csd >= FD_SETSIZE) {
        ap_log_error(APLOG_MARK, APLOG_WARNING, 0, NULL,
                     "filedescriptor (%u) larger than FD_SETSIZE (%u) "
                     "found, you probably need to rebuild Apache with a "
                     "larger FD_SETSIZE", csd, FD_SETSIZE);
        apr_socket_close(sock);
        return;
    }

    ap_create_sb_handle(&sbh, p, 0, my_child_num);
    current_conn = ap_run_create_connection(p, ap_server_conf,
                                            sock, conn_id, sbh,
                                            bucket_alloc);

    if (current_conn) {
        ap_process_connection(current_conn, sock);
        ap_lingering_close(current_conn);
    }
}

static int32 worker_thread(void * dummy)
{
    proc_info * ti = dummy;
    int child_slot = ti->slot;
    apr_pool_t *tpool = ti->tpool;
    apr_allocator_t *allocator;
    apr_socket_t *csd = NULL;
    apr_pool_t *ptrans;		/* Pool for per-transaction stuff */
    apr_bucket_alloc_t *bucket_alloc;
    apr_socket_t *sd = NULL;
    apr_status_t rv = APR_EINIT;
    int srv , n;
    int curr_pollfd = 0, last_pollfd = 0;
    sigset_t sig_mask;
    int requests_this_child = ap_max_requests_per_thread;
    apr_pollfd_t *pollset;
    /* each worker thread is in control of its own destiny...*/
    int this_worker_should_exit = 0; 
    free(ti);

    mpm_state = AP_MPMQ_STARTING;

    on_exit_thread(check_restart, (void*)child_slot);
          
    /* block the signals for this thread */
    sigfillset(&sig_mask);
    sigprocmask(SIG_BLOCK, &sig_mask, NULL);

    apr_allocator_create(&allocator);
    apr_allocator_max_free_set(allocator, ap_max_mem_free);
    apr_pool_create_ex(&ptrans, tpool, NULL, allocator);
    apr_allocator_owner_set(allocator, ptrans);

    apr_pool_tag(ptrans, "transaction");

    bucket_alloc = apr_bucket_alloc_create_ex(allocator);

    apr_thread_mutex_lock(worker_thread_count_mutex);
    worker_thread_count++;
    apr_thread_mutex_unlock(worker_thread_count_mutex);

    (void) ap_update_child_status_from_indexes(0, child_slot, SERVER_STARTING,
                                               (request_rec*)NULL);
                                  
    apr_poll_setup(&pollset, num_listening_sockets + 1, tpool);
    for(n=0 ; n <= num_listening_sockets ; n++)
        apr_poll_socket_add(pollset, listening_sockets[n], APR_POLLIN);

    mpm_state = AP_MPMQ_RUNNING;

    while (1) {
        /* If we're here, then chances are (unless we're the first thread created) 
         * we're going to be held up in the accept mutex, so doing this here
         * shouldn't hurt performance.
         */

        this_worker_should_exit |= (ap_max_requests_per_thread != 0) && (requests_this_child <= 0);
        
        if (this_worker_should_exit) break;

        (void) ap_update_child_status_from_indexes(0, child_slot, SERVER_READY,
                                                   (request_rec*)NULL);