threaded.c

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

#else
    if (!one_process) {
	apr_signal(SIGSEGV, sig_coredump);
#ifdef SIGBUS
	apr_signal(SIGBUS, sig_coredump);
#endif /* SIGBUS */
#ifdef SIGABORT
	apr_signal(SIGABORT, sig_coredump);
#endif /* SIGABORT */
#ifdef SIGABRT
	apr_signal(SIGABRT, sig_coredump);
#endif /* SIGABRT */
#ifdef SIGILL
	apr_signal(SIGILL, sig_coredump);
#endif /* SIGILL */
#ifdef SIGXCPU
	apr_signal(SIGXCPU, SIG_DFL);
#endif /* SIGXCPU */
#ifdef SIGXFSZ
	apr_signal(SIGXFSZ, SIG_DFL);
#endif /* SIGXFSZ */
    }

    apr_signal(SIGTERM, sig_term);
#ifdef SIGHUP
    apr_signal(SIGHUP, restart);
#endif /* SIGHUP */
#ifdef SIGWINCH
    apr_signal(SIGWINCH, restart);
#endif /* SIGWINCH */
#ifdef SIGPIPE
    apr_signal(SIGPIPE, SIG_IGN);
#endif /* SIGPIPE */

#endif
}

/*****************************************************************
 * 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, int my_thread_num)
{
    conn_rec *current_conn;
    long conn_id = AP_ID_FROM_CHILD_THREAD(my_child_num, my_thread_num);
    int csd;

    (void) apr_os_sock_get(&csd, sock);

    if (csd >= FD_SETSIZE) {
        ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, NULL,
                     "new file descriptor %d is too large; you probably need "
                     "to rebuild Apache with a larger FD_SETSIZE "
                     "(currently %d)", 
                     csd, FD_SETSIZE);
        apr_socket_close(sock);
        return;
    }

    ap_sock_disable_nagle(sock);

    current_conn = ap_new_connection(p, ap_server_conf, sock, conn_id);
    if (current_conn) {
        ap_process_connection(current_conn);
        ap_lingering_close(current_conn);
    }
}
/* Sets workers_may_exit if we received a character on the pipe_of_death */
static void check_pipe_of_death(void)
{
    apr_lock_acquire(pipe_of_death_mutex);
    if (!workers_may_exit) {
        apr_status_t ret;
        char pipe_read_char;
	apr_size_t n = 1;

        ret = apr_recv(listensocks[0], &pipe_read_char, &n);
        if (APR_STATUS_IS_EAGAIN(ret)) {
            /* It lost the lottery. It must continue to suffer
             * through a life of servitude. */
        }
        else {
            /* It won the lottery (or something else is very
             * wrong). Embrace death with open arms. */
            workers_may_exit = 1;
        }
    }
    apr_lock_release(pipe_of_death_mutex);
}

static void * worker_thread(void * dummy)
{
    proc_info * ti = dummy;
    int process_slot = ti->pid;
    int thread_slot = ti->tid;
    apr_pool_t *tpool = ti->tpool;
    apr_socket_t *csd = NULL;
    apr_pool_t *ptrans;		/* Pool for per-transaction stuff */
    apr_socket_t *sd = NULL;
    int n;
    int curr_pollfd, last_pollfd = 0;
    apr_pollfd_t *pollset;
    apr_status_t rv;

    free(ti);

    apr_pool_create(&ptrans, tpool);

    apr_lock_acquire(worker_thread_count_mutex);
    worker_thread_count++;
    apr_lock_release(worker_thread_count_mutex);

    apr_poll_setup(&pollset, num_listensocks+1, tpool);
    for(n=0 ; n <= num_listensocks ; ++n)
	apr_poll_socket_add(pollset, listensocks[n], APR_POLLIN);

    /* TODO: Switch to a system where threads reuse the results from earlier
       poll calls - manoj */
    while (1) {
        workers_may_exit |= (ap_max_requests_per_child != 0) && (requests_this_child <= 0);
        if (workers_may_exit) break;

        (void) ap_update_child_status(process_slot, thread_slot, SERVER_READY, 
                                      (request_rec *) NULL);
        if ((rv = SAFE_ACCEPT(apr_lock_acquire(accept_mutex)))
            != APR_SUCCESS) {
            ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
                         "apr_lock_acquire failed. Attempting to shutdown "
                         "process gracefully.");
            workers_may_exit = 1;
        }

        while (!workers_may_exit) {
	    apr_status_t ret;
	    apr_int16_t event;

            ret = apr_poll(pollset, &n, -1);
            if (ret != APR_SUCCESS) {
                if (APR_STATUS_IS_EINTR(ret)) {
                    continue;
                }

                /* apr_poll() will only return errors in catastrophic
                 * circumstances. Let's try exiting gracefully, for now. */
                ap_log_error(APLOG_MARK, APLOG_ERR, ret, (const server_rec *)
                             ap_server_conf, "apr_poll: (listen)");
                workers_may_exit = 1;
            }

            if (workers_may_exit) break;

	    apr_poll_revents_get(&event, listensocks[0], pollset);
            if (event & APR_POLLIN) {
                /* A process got a signal on the shutdown pipe. Check if we're
                 * the lucky process to die. */
                check_pipe_of_death();
                continue;
            }

            if (num_listensocks == 1) {
                sd = ap_listeners->sd;
                goto got_fd;
            }
            else {
                /* find a listener */
                curr_pollfd = last_pollfd;
                do {
                    curr_pollfd++;
                    if (curr_pollfd > num_listensocks) {
                        curr_pollfd = 1;
                    }
                    /* XXX: Should we check for POLLERR? */
		    apr_poll_revents_get(&event, listensocks[curr_pollfd], pollset);
                    if (event & APR_POLLIN) {
                        last_pollfd = curr_pollfd;
			sd=listensocks[curr_pollfd];
                        goto got_fd;
                    }
                } while (curr_pollfd != last_pollfd);
            }
        }
    got_fd:
        if (!workers_may_exit) {
            if ((rv = apr_accept(&csd, sd, ptrans)) != APR_SUCCESS) {
                csd = NULL;
                ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, 
                             "apr_accept");
            }
            if ((rv = SAFE_ACCEPT(apr_lock_release(accept_mutex)))
                != APR_SUCCESS) {
                ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
                             "apr_lock_release failed. Attempting to shutdown "
                             "process gracefully.");
                workers_may_exit = 1;
            }
            if (csd != NULL) {
                process_socket(ptrans, csd, process_slot, thread_slot);
                requests_this_child--;
            }
        }
        else {
            if ((rv = SAFE_ACCEPT(apr_lock_release(accept_mutex)))
                != APR_SUCCESS) {
                ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
                             "apr_lock_release failed. Attempting to shutdown "
                             "process gracefully.");
                workers_may_exit = 1;
            }
            break;
        }
        apr_pool_clear(ptrans);
    }

    apr_pool_destroy(tpool);
    ap_update_child_status(process_slot, thread_slot, SERVER_DEAD,
        (request_rec *) NULL);
    apr_lock_acquire(worker_thread_count_mutex);
    worker_thread_count--;
    if (worker_thread_count == 0) {
        /* All the threads have exited, now finish the shutdown process
         * by signalling the sigwait thread */
        kill(ap_my_pid, SIGTERM);
    }
    apr_lock_release(worker_thread_count_mutex);

    return NULL;
}

static int check_signal(int signum)
{
    switch (signum) {
        case SIGTERM:
        case SIGINT:
            just_die(signum);
            return 1;
    }                                                                           
    return 0;
}

static void child_main(int child_num_arg)
{
    apr_thread_t *thread;
    apr_threadattr_t *thread_attr;
    int i;
    int my_child_num = child_num_arg;
    proc_info *my_info = NULL;
    ap_listen_rec *lr;
    apr_status_t rv;


    ap_my_pid = getpid();
    apr_pool_create(&pchild, pconf);

    /*stuff to do before we switch id's, so we have permissions.*/
    reopen_scoreboard(pchild);

    rv = SAFE_ACCEPT(apr_lock_child_init(&accept_mutex, lock_fname,
                     pchild));
    if (rv != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
                     "Couldn't initialize cross-process lock in child");
        clean_child_exit(APEXIT_CHILDFATAL);
    }

    if (unixd_setup_child()) {
	clean_child_exit(APEXIT_CHILDFATAL);
    }

    ap_run_child_init(pchild, ap_server_conf);

    /*done with init critical section */

    rv = apr_setup_signal_thread();
    if (rv != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
                     "Couldn't initialize signal thread");
        clean_child_exit(APEXIT_CHILDFATAL);
    }

    requests_this_child = ap_max_requests_per_child;
    
    /* Set up the pollfd array */
    listensocks = apr_pcalloc(pchild,
			    sizeof(*listensocks) * (num_listensocks + 1));
#if APR_FILES_AS_SOCKETS
    apr_socket_from_file(&listensocks[0], pipe_of_death_in);
#endif
    for (lr = ap_listeners, i = 1; i <= num_listensocks; lr = lr->next, ++i)
	listensocks[i]=lr->sd;

    /* Setup worker threads */

    worker_thread_count = 0;
    apr_lock_create(&worker_thread_count_mutex, APR_MUTEX, APR_INTRAPROCESS,
                    NULL, pchild);
    apr_lock_create(&pipe_of_death_mutex, APR_MUTEX, APR_INTRAPROCESS, 
                    NULL, pchild);
    apr_threadattr_create(&thread_attr, pchild);
    apr_threadattr_detach_set(thread_attr);

    rv = apr_create_signal_thread(&thread, thread_attr, check_signal, pchild);
    if (rv != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
                     "Couldn't create signal thread");
        clean_child_exit(APEXIT_CHILDFATAL);
    }

    for (i=0; i < ap_threads_per_child - 1; i++) {

	my_info = (proc_info *)malloc(sizeof(proc_info));
        if (my_info == NULL) {
            ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
		         "malloc: out of memory");
            clean_child_exit(APEXIT_CHILDFATAL);
        }
	my_info->pid = my_child_num;
        my_info->tid = i;
	my_info->sd = 0;
	apr_pool_create(&my_info->tpool, pchild);
	
	/* We are creating threads right now */
	(void) ap_update_child_status(my_child_num, i, SERVER_STARTING, 
				      (request_rec *) NULL);
	if ((rv = apr_thread_create(&thread, thread_attr, worker_thread, my_info, pchild))) {
	    ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf,
			 "apr_thread_create: unable to create worker thread");
            /* 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 if we exit. */
            sleep(10);
	    clean_child_exit(APEXIT_CHILDFATAL);
	}
	/* We let each thread update it's own scoreboard entry.  This is done
	 * because it let's us deal with tid better.
	 */
    }
    my_info = (proc_info *)malloc(sizeof(proc_info));
    if (my_info == NULL) {
        ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
                    "malloc: out of memory");
        clean_child_exit(APEXIT_CHILDFATAL);