view src/os/win32/ngx_process_cycle.c @ 9300:5be23505292b default tip

SSI: fixed incorrect or duplicate stub output. Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set if there are data in the first buffer sent in the subrequest. As a result, following the change mentioned this flag cannot be used to prevent duplicate ngx_http_ssi_stub_output() calls, since it is not set if there was already some output, but the first buffer was empty. Still, when there are multiple subrequests, even an empty subrequest response might be delayed by the postpone filter, leading to a second call of ngx_http_ssi_stub_output() during finalization from ngx_http_writer() the subreqest buffers are released by the postpone filter. Since r->request_output is not set after the first call, this resulted in duplicate stub output. Additionally, checking only the first buffer might be wrong in some unusual cases. For example, the first buffer might be empty if $r->flush() is called before printing any data in the embedded Perl module. Depending on the postpone_output value and corresponding sizes, this issue can result in either duplicate or unexpected stub output, or "zero size buf in writer" alerts. Following 8124:f5515e727656 (1.23.4), it became slightly easier to reproduce the issue, as empty static files and empty cache items now result in a response with an empty buffer. Before the change, an empty proxied response can be used to reproduce the issue. Fix is check all buffers and set r->request_output if any non-empty buffers are sent. This ensures that all unusual cases of non-empty responses are covered, and also that r->request_output will be set after the first stub output, preventing duplicate output. Reported by Jan Gassen.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 04 Jul 2024 17:41:28 +0300
parents 791ead216b03
children
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#include <nginx.h>


static void ngx_console_init(ngx_cycle_t *cycle);
static int __stdcall ngx_console_handler(u_long type);
static ngx_int_t ngx_create_signal_events(ngx_cycle_t *cycle);
static ngx_int_t ngx_start_worker_processes(ngx_cycle_t *cycle, ngx_int_t type);
static void ngx_reopen_worker_processes(ngx_cycle_t *cycle);
static void ngx_quit_worker_processes(ngx_cycle_t *cycle, ngx_uint_t old);
static void ngx_terminate_worker_processes(ngx_cycle_t *cycle);
static ngx_uint_t ngx_reap_worker(ngx_cycle_t *cycle, HANDLE h);
static void ngx_master_process_exit(ngx_cycle_t *cycle);
static void ngx_worker_process_cycle(ngx_cycle_t *cycle, char *mevn);
static void ngx_worker_process_exit(ngx_cycle_t *cycle);
static ngx_thread_value_t __stdcall ngx_worker_thread(void *data);
static ngx_thread_value_t __stdcall ngx_cache_manager_thread(void *data);
static void ngx_cache_manager_process_handler(void);
static ngx_thread_value_t __stdcall ngx_cache_loader_thread(void *data);


ngx_uint_t     ngx_process;
ngx_uint_t     ngx_worker;
ngx_pid_t      ngx_pid;
ngx_pid_t      ngx_parent;

ngx_uint_t     ngx_inherited;
ngx_pid_t      ngx_new_binary;

sig_atomic_t   ngx_terminate;
sig_atomic_t   ngx_quit;
sig_atomic_t   ngx_reopen;
sig_atomic_t   ngx_reconfigure;
ngx_uint_t     ngx_exiting;


HANDLE         ngx_master_process_event;
char           ngx_master_process_event_name[NGX_PROCESS_SYNC_NAME];

static HANDLE  ngx_stop_event;
static char    ngx_stop_event_name[NGX_PROCESS_SYNC_NAME];
static HANDLE  ngx_quit_event;
static char    ngx_quit_event_name[NGX_PROCESS_SYNC_NAME];
static HANDLE  ngx_reopen_event;
static char    ngx_reopen_event_name[NGX_PROCESS_SYNC_NAME];
static HANDLE  ngx_reload_event;
static char    ngx_reload_event_name[NGX_PROCESS_SYNC_NAME];

HANDLE         ngx_cache_manager_mutex;
char           ngx_cache_manager_mutex_name[NGX_PROCESS_SYNC_NAME];
HANDLE         ngx_cache_manager_event;


void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    u_long      nev, ev, timeout;
    ngx_err_t   err;
    ngx_int_t   n;
    ngx_msec_t  timer;
    ngx_uint_t  live;
    HANDLE      events[MAXIMUM_WAIT_OBJECTS];

    ngx_sprintf((u_char *) ngx_master_process_event_name,
                "ngx_master_%s%Z", ngx_unique);

    if (ngx_process == NGX_PROCESS_WORKER) {
        ngx_worker_process_cycle(cycle, ngx_master_process_event_name);
        return;
    }

    ngx_log_debug0(NGX_LOG_DEBUG_CORE, cycle->log, 0, "master started");

    ngx_console_init(cycle);

    SetEnvironmentVariable("ngx_unique", ngx_unique);

    ngx_master_process_event = CreateEvent(NULL, 1, 0,
                                           ngx_master_process_event_name);
    if (ngx_master_process_event == NULL) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "CreateEvent(\"%s\") failed",
                      ngx_master_process_event_name);
        exit(2);
    }

    if (ngx_create_signal_events(cycle) != NGX_OK) {
        exit(2);
    }

    ngx_sprintf((u_char *) ngx_cache_manager_mutex_name,
                "ngx_cache_manager_mutex_%s%Z", ngx_unique);

    ngx_cache_manager_mutex = CreateMutex(NULL, 0,
                                          ngx_cache_manager_mutex_name);
    if (ngx_cache_manager_mutex == NULL) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                   "CreateMutex(\"%s\") failed", ngx_cache_manager_mutex_name);
        exit(2);
    }


    events[0] = ngx_stop_event;
    events[1] = ngx_quit_event;
    events[2] = ngx_reopen_event;
    events[3] = ngx_reload_event;

    ngx_close_listening_sockets(cycle);

    if (ngx_start_worker_processes(cycle, NGX_PROCESS_RESPAWN) == 0) {
        exit(2);
    }

    timer = 0;
    timeout = INFINITE;

    for ( ;; ) {

        nev = 4;
        for (n = 0; n < ngx_last_process; n++) {
            if (ngx_processes[n].handle) {
                events[nev++] = ngx_processes[n].handle;
            }
        }

        if (timer) {
            timeout = timer > ngx_current_msec ? timer - ngx_current_msec : 0;
        }

        ev = WaitForMultipleObjects(nev, events, 0, timeout);

        err = ngx_errno;
        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_CORE, cycle->log, 0,
                       "master WaitForMultipleObjects: %ul", ev);

        if (ev == WAIT_OBJECT_0) {
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exiting");

            if (ResetEvent(ngx_stop_event) == 0) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                              "ResetEvent(\"%s\") failed", ngx_stop_event_name);
            }

            if (timer == 0) {
                timer = ngx_current_msec + 5000;
            }

            ngx_terminate = 1;
            ngx_quit_worker_processes(cycle, 0);

            continue;
        }

        if (ev == WAIT_OBJECT_0 + 1) {
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "shutting down");

            if (ResetEvent(ngx_quit_event) == 0) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                              "ResetEvent(\"%s\") failed", ngx_quit_event_name);
            }

            ngx_quit = 1;
            ngx_quit_worker_processes(cycle, 0);

            continue;
        }

        if (ev == WAIT_OBJECT_0 + 2) {
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");

            if (ResetEvent(ngx_reopen_event) == 0) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                              "ResetEvent(\"%s\") failed",
                              ngx_reopen_event_name);
            }

            ngx_reopen_files(cycle, -1);
            ngx_reopen_worker_processes(cycle);

            continue;
        }

        if (ev == WAIT_OBJECT_0 + 3) {
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reconfiguring");

            if (ResetEvent(ngx_reload_event) == 0) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                              "ResetEvent(\"%s\") failed",
                              ngx_reload_event_name);
            }

            cycle = ngx_init_cycle(cycle);
            if (cycle == NULL) {
                cycle = (ngx_cycle_t *) ngx_cycle;
                continue;
            }

            ngx_cycle = cycle;

            ngx_close_listening_sockets(cycle);

            if (ngx_start_worker_processes(cycle, NGX_PROCESS_JUST_RESPAWN)) {
                ngx_quit_worker_processes(cycle, 1);
            }

            continue;
        }

        if (ev > WAIT_OBJECT_0 + 3 && ev < WAIT_OBJECT_0 + nev) {

            ngx_log_debug0(NGX_LOG_DEBUG_CORE, cycle->log, 0, "reap worker");

            live = ngx_reap_worker(cycle, events[ev]);

            if (!live && (ngx_terminate || ngx_quit)) {
                ngx_master_process_exit(cycle);
            }

            continue;
        }

        if (ev == WAIT_TIMEOUT) {
            ngx_terminate_worker_processes(cycle);

            ngx_master_process_exit(cycle);
        }

        if (ev == WAIT_FAILED) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, err,
                          "WaitForMultipleObjects() failed");

            continue;
        }

        ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
            "WaitForMultipleObjects() returned unexpected value %ul", ev);
    }
}


static void
ngx_console_init(ngx_cycle_t *cycle)
{
    ngx_core_conf_t  *ccf;

    ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);

    if (ccf->daemon) {
        if (FreeConsole() == 0) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "FreeConsole() failed");
        }

        return;
    }

    if (SetConsoleCtrlHandler(ngx_console_handler, 1) == 0) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "SetConsoleCtrlHandler() failed");
    }
}


static int __stdcall
ngx_console_handler(u_long type)
{
    char  *msg;

    switch (type) {

    case CTRL_C_EVENT:
        msg = "Ctrl-C pressed, exiting";
        break;

    case CTRL_BREAK_EVENT:
        msg = "Ctrl-Break pressed, exiting";
        break;

    case CTRL_CLOSE_EVENT:
        msg = "console closing, exiting";
        break;

    case CTRL_LOGOFF_EVENT:
        msg = "user logs off, exiting";
        break;

    default:
        return 0;
    }

    ngx_log_error(NGX_LOG_NOTICE, ngx_cycle->log, 0, msg);

    if (ngx_stop_event == NULL) {
        return 1;
    }

    if (SetEvent(ngx_stop_event) == 0) {
        ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
                      "SetEvent(\"%s\") failed", ngx_stop_event_name);
    }

    return 1;
}


static ngx_int_t
ngx_create_signal_events(ngx_cycle_t *cycle)
{
    ngx_sprintf((u_char *) ngx_stop_event_name,
                "Global\\ngx_stop_%s%Z", ngx_unique);

    ngx_stop_event = CreateEvent(NULL, 1, 0, ngx_stop_event_name);
    if (ngx_stop_event == NULL) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "CreateEvent(\"%s\") failed", ngx_stop_event_name);
        return NGX_ERROR;
    }


    ngx_sprintf((u_char *) ngx_quit_event_name,
                "Global\\ngx_quit_%s%Z", ngx_unique);

    ngx_quit_event = CreateEvent(NULL, 1, 0, ngx_quit_event_name);
    if (ngx_quit_event == NULL) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "CreateEvent(\"%s\") failed", ngx_quit_event_name);
        return NGX_ERROR;
    }


    ngx_sprintf((u_char *) ngx_reopen_event_name,
                "Global\\ngx_reopen_%s%Z", ngx_unique);

    ngx_reopen_event = CreateEvent(NULL, 1, 0, ngx_reopen_event_name);
    if (ngx_reopen_event == NULL) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "CreateEvent(\"%s\") failed", ngx_reopen_event_name);
        return NGX_ERROR;
    }


    ngx_sprintf((u_char *) ngx_reload_event_name,
                "Global\\ngx_reload_%s%Z", ngx_unique);

    ngx_reload_event = CreateEvent(NULL, 1, 0, ngx_reload_event_name);
    if (ngx_reload_event == NULL) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "CreateEvent(\"%s\") failed", ngx_reload_event_name);
        return NGX_ERROR;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_start_worker_processes(ngx_cycle_t *cycle, ngx_int_t type)
{
    ngx_int_t         n;
    ngx_core_conf_t  *ccf;

    ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "start worker processes");

    ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);

    for (n = 0; n < ccf->worker_processes; n++) {
        if (ngx_spawn_process(cycle, "worker", type) == NGX_INVALID_PID) {
            break;
        }
    }

    return n;
}


static void
ngx_reopen_worker_processes(ngx_cycle_t *cycle)
{
    ngx_int_t  n;

    for (n = 0; n < ngx_last_process; n++) {

        if (ngx_processes[n].handle == NULL) {
            continue;
        }

        if (SetEvent(ngx_processes[n].reopen) == 0) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "SetEvent(\"%s\") failed",
                          ngx_processes[n].reopen_event);
        }
    }
}


static void
ngx_quit_worker_processes(ngx_cycle_t *cycle, ngx_uint_t old)
{
    ngx_int_t  n;

    for (n = 0; n < ngx_last_process; n++) {

        ngx_log_debug5(NGX_LOG_DEBUG_CORE, cycle->log, 0,
                       "process: %d %P %p e:%d j:%d",
                       n,
                       ngx_processes[n].pid,
                       ngx_processes[n].handle,
                       ngx_processes[n].exiting,
                       ngx_processes[n].just_spawn);

        if (old && ngx_processes[n].just_spawn) {
            ngx_processes[n].just_spawn = 0;
            continue;
        }

        if (ngx_processes[n].handle == NULL) {
            continue;
        }

        if (SetEvent(ngx_processes[n].quit) == 0) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "SetEvent(\"%s\") failed",
                          ngx_processes[n].quit_event);
        }

        ngx_processes[n].exiting = 1;
    }
}


static void
ngx_terminate_worker_processes(ngx_cycle_t *cycle)
{
    ngx_int_t  n;

    for (n = 0; n < ngx_last_process; n++) {

        if (ngx_processes[n].handle == NULL) {
            continue;
        }

        if (TerminateProcess(ngx_processes[n].handle, 0) == 0) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "TerminateProcess(\"%p\") failed",
                          ngx_processes[n].handle);
        }

        ngx_processes[n].exiting = 1;

        ngx_close_handle(ngx_processes[n].reopen);
        ngx_close_handle(ngx_processes[n].quit);
        ngx_close_handle(ngx_processes[n].term);
        ngx_close_handle(ngx_processes[n].handle);
    }
}


static ngx_uint_t
ngx_reap_worker(ngx_cycle_t *cycle, HANDLE h)
{
    u_long     code;
    ngx_int_t  n;

    for (n = 0; n < ngx_last_process; n++) {

        if (ngx_processes[n].handle != h) {
            continue;
        }

        if (GetExitCodeProcess(h, &code) == 0) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "GetExitCodeProcess(%P) failed",
                          ngx_processes[n].pid);
        }

        ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0,
                      "%s process %P exited with code %Xl",
                      ngx_processes[n].name, ngx_processes[n].pid, code);

        ngx_close_handle(ngx_processes[n].reopen);
        ngx_close_handle(ngx_processes[n].quit);
        ngx_close_handle(ngx_processes[n].term);
        ngx_close_handle(h);

        ngx_processes[n].handle = NULL;
        ngx_processes[n].term = NULL;
        ngx_processes[n].quit = NULL;
        ngx_processes[n].reopen = NULL;

        if (!ngx_processes[n].exiting && !ngx_terminate && !ngx_quit) {

            if (ngx_spawn_process(cycle, ngx_processes[n].name, n)
                == NGX_INVALID_PID)
            {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                              "could not respawn %s", ngx_processes[n].name);

                if (n == ngx_last_process - 1) {
                    ngx_last_process--;
                }
            }
        }

        goto found;
    }

    ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "unknown process handle %p", h);

found:

    for (n = 0; n < ngx_last_process; n++) {

        ngx_log_debug5(NGX_LOG_DEBUG_CORE, cycle->log, 0,
                       "process: %d %P %p e:%d j:%d",
                       n,
                       ngx_processes[n].pid,
                       ngx_processes[n].handle,
                       ngx_processes[n].exiting,
                       ngx_processes[n].just_spawn);

        if (ngx_processes[n].handle) {
            return 1;
        }
    }

    return 0;
}


static void
ngx_master_process_exit(ngx_cycle_t *cycle)
{
    ngx_uint_t  i;

    ngx_delete_pidfile(cycle);

    ngx_close_handle(ngx_cache_manager_mutex);
    ngx_close_handle(ngx_stop_event);
    ngx_close_handle(ngx_quit_event);
    ngx_close_handle(ngx_reopen_event);
    ngx_close_handle(ngx_reload_event);
    ngx_close_handle(ngx_master_process_event);

    ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exit");

    for (i = 0; cycle->modules[i]; i++) {
        if (cycle->modules[i]->exit_master) {
            cycle->modules[i]->exit_master(cycle);
        }
    }

    ngx_destroy_pool(cycle->pool);

    exit(0);
}


static void
ngx_worker_process_cycle(ngx_cycle_t *cycle, char *mevn)
{
    char        wtevn[NGX_PROCESS_SYNC_NAME];
    char        wqevn[NGX_PROCESS_SYNC_NAME];
    char        wroevn[NGX_PROCESS_SYNC_NAME];
    HANDLE      mev, events[3];
    u_long      nev, ev;
    ngx_err_t   err;
    ngx_tid_t   wtid, cmtid, cltid;
    ngx_log_t  *log;

    log = cycle->log;

    ngx_log_debug0(NGX_LOG_DEBUG_CORE, log, 0, "worker started");

    ngx_sprintf((u_char *) wtevn, "ngx_worker_term_%P%Z", ngx_pid);
    events[0] = CreateEvent(NULL, 1, 0, wtevn);
    if (events[0] == NULL) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
                      "CreateEvent(\"%s\") failed", wtevn);
        goto failed;
    }

    ngx_sprintf((u_char *) wqevn, "ngx_worker_quit_%P%Z", ngx_pid);
    events[1] = CreateEvent(NULL, 1, 0, wqevn);
    if (events[1] == NULL) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
                      "CreateEvent(\"%s\") failed", wqevn);
        goto failed;
    }

    ngx_sprintf((u_char *) wroevn, "ngx_worker_reopen_%P%Z", ngx_pid);
    events[2] = CreateEvent(NULL, 1, 0, wroevn);
    if (events[2] == NULL) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
                      "CreateEvent(\"%s\") failed", wroevn);
        goto failed;
    }

    mev = OpenEvent(EVENT_MODIFY_STATE, 0, mevn);
    if (mev == NULL) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
                      "OpenEvent(\"%s\") failed", mevn);
        goto failed;
    }

    if (SetEvent(mev) == 0) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
                      "SetEvent(\"%s\") failed", mevn);
        goto failed;
    }


    ngx_sprintf((u_char *) ngx_cache_manager_mutex_name,
                "ngx_cache_manager_mutex_%s%Z", ngx_unique);

    ngx_cache_manager_mutex = OpenMutex(SYNCHRONIZE, 0,
                                        ngx_cache_manager_mutex_name);
    if (ngx_cache_manager_mutex == NULL) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
                      "OpenMutex(\"%s\") failed", ngx_cache_manager_mutex_name);
        goto failed;
    }

    ngx_cache_manager_event = CreateEvent(NULL, 1, 0, NULL);
    if (ngx_cache_manager_event == NULL) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "CreateEvent(\"ngx_cache_manager_event\") failed");
        goto failed;
    }


    if (ngx_create_thread(&wtid, ngx_worker_thread, NULL, log) != 0) {
        goto failed;
    }

    if (ngx_create_thread(&cmtid, ngx_cache_manager_thread, NULL, log) != 0) {
        goto failed;
    }

    if (ngx_create_thread(&cltid, ngx_cache_loader_thread, NULL, log) != 0) {
        goto failed;
    }

    for ( ;; ) {
        ev = WaitForMultipleObjects(3, events, 0, INFINITE);

        err = ngx_errno;
        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_CORE, log, 0,
                       "worker WaitForMultipleObjects: %ul", ev);

        if (ev == WAIT_OBJECT_0) {
            ngx_terminate = 1;
            ngx_log_error(NGX_LOG_NOTICE, log, 0, "exiting");

            if (ResetEvent(events[0]) == 0) {
                ngx_log_error(NGX_LOG_ALERT, log, 0,
                              "ResetEvent(\"%s\") failed", wtevn);
            }

            break;
        }

        if (ev == WAIT_OBJECT_0 + 1) {
            ngx_quit = 1;
            ngx_log_error(NGX_LOG_NOTICE, log, 0, "gracefully shutting down");
            break;
        }

        if (ev == WAIT_OBJECT_0 + 2) {
            ngx_reopen = 1;
            ngx_log_error(NGX_LOG_NOTICE, log, 0, "reopening logs");

            if (ResetEvent(events[2]) == 0) {
                ngx_log_error(NGX_LOG_ALERT, log, 0,
                              "ResetEvent(\"%s\") failed", wroevn);
            }

            continue;
        }

        if (ev == WAIT_FAILED) {
            ngx_log_error(NGX_LOG_ALERT, log, err,
                          "WaitForMultipleObjects() failed");

            goto failed;
        }
    }

    /* wait threads */

    if (SetEvent(ngx_cache_manager_event) == 0) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
                      "SetEvent(\"ngx_cache_manager_event\") failed");
    }

    events[1] = wtid;
    events[2] = cmtid;

    nev = 3;

    for ( ;; ) {
        ev = WaitForMultipleObjects(nev, events, 0, INFINITE);

        err = ngx_errno;
        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_CORE, log, 0,
                       "worker exit WaitForMultipleObjects: %ul", ev);

        if (ev == WAIT_OBJECT_0) {
            break;
        }

        if (ev == WAIT_OBJECT_0 + 1) {
            if (nev == 2) {
                break;
            }

            events[1] = events[2];
            nev = 2;
            continue;
        }

        if (ev == WAIT_OBJECT_0 + 2) {
            nev = 2;
            continue;
        }

        if (ev == WAIT_FAILED) {
            ngx_log_error(NGX_LOG_ALERT, log, err,
                          "WaitForMultipleObjects() failed");
            break;
        }
    }

    ngx_close_handle(ngx_cache_manager_event);
    ngx_close_handle(events[0]);
    ngx_close_handle(events[1]);
    ngx_close_handle(events[2]);
    ngx_close_handle(mev);

    ngx_worker_process_exit(cycle);

failed:

    exit(2);
}


static ngx_thread_value_t __stdcall
ngx_worker_thread(void *data)
{
    ngx_int_t     n;
    ngx_time_t   *tp;
    ngx_cycle_t  *cycle;

    tp = ngx_timeofday();
    srand((ngx_pid << 16) ^ (unsigned) tp->sec ^ tp->msec);

    cycle = (ngx_cycle_t *) ngx_cycle;

    for (n = 0; cycle->modules[n]; n++) {
        if (cycle->modules[n]->init_process) {
            if (cycle->modules[n]->init_process(cycle) == NGX_ERROR) {
                /* fatal */
                exit(2);
            }
        }
    }

    while (!ngx_quit) {

        if (ngx_exiting) {
            if (ngx_event_no_timers_left() == NGX_OK) {
                break;
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_CORE, cycle->log, 0, "worker cycle");

        ngx_process_events_and_timers(cycle);

        if (ngx_terminate) {
            return 0;
        }

        if (ngx_quit) {
            ngx_quit = 0;

            if (!ngx_exiting) {
                ngx_exiting = 1;
                ngx_set_shutdown_timer(cycle);
                ngx_close_listening_sockets(cycle);
                ngx_close_idle_connections(cycle);
                ngx_event_process_posted(cycle, &ngx_posted_events);
            }
        }

        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_reopen_files(cycle, -1);
        }
    }

    ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exiting");

    return 0;
}


static void
ngx_worker_process_exit(ngx_cycle_t *cycle)
{
    ngx_uint_t         i;
    ngx_connection_t  *c;

    ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exit");

    for (i = 0; cycle->modules[i]; i++) {
        if (cycle->modules[i]->exit_process) {
            cycle->modules[i]->exit_process(cycle);
        }
    }

    if (ngx_exiting && !ngx_terminate) {
        c = cycle->connections;
        for (i = 0; i < cycle->connection_n; i++) {
            if (c[i].fd != (ngx_socket_t) -1
                && c[i].read
                && !c[i].read->accept
                && !c[i].read->channel
                && !c[i].read->resolver)
            {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                              "*%uA open socket #%d left in connection %ui",
                              c[i].number, c[i].fd, i);
            }
        }
    }

    ngx_destroy_pool(cycle->pool);

    exit(0);
}


static ngx_thread_value_t __stdcall
ngx_cache_manager_thread(void *data)
{
    u_long        ev;
    HANDLE        events[2];
    ngx_err_t     err;
    ngx_cycle_t  *cycle;

    cycle = (ngx_cycle_t *) ngx_cycle;

    events[0] = ngx_cache_manager_event;
    events[1] = ngx_cache_manager_mutex;

    for ( ;; ) {
        ev = WaitForMultipleObjects(2, events, 0, INFINITE);

        err = ngx_errno;
        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_CORE, cycle->log, 0,
                       "cache manager WaitForMultipleObjects: %ul", ev);

        if (ev == WAIT_FAILED) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, err,
                          "WaitForMultipleObjects() failed");
        }

        /*
         * ev == WAIT_OBJECT_0
         * ev == WAIT_OBJECT_0 + 1
         * ev == WAIT_ABANDONED_0 + 1
         */

        if (ngx_terminate || ngx_quit || ngx_exiting) {
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exiting");
            return 0;
        }

        break;
    }

    for ( ;; ) {

        if (ngx_terminate || ngx_quit || ngx_exiting) {
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exiting");
            break;
        }

        ngx_cache_manager_process_handler();
    }

    if (ReleaseMutex(ngx_cache_manager_mutex) == 0) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "ReleaseMutex() failed");
    }

    return 0;
}


static void
ngx_cache_manager_process_handler(void)
{
    u_long        ev;
    ngx_uint_t    i;
    ngx_msec_t    next, n;
    ngx_path_t  **path;

    next = 60 * 60 * 1000;

    path = ngx_cycle->paths.elts;
    for (i = 0; i < ngx_cycle->paths.nelts; i++) {

        if (path[i]->manager) {
            n = path[i]->manager(path[i]->data);

            next = (n <= next) ? n : next;

            ngx_time_update();
        }
    }

    if (next == 0) {
        next = 1;
    }

    ev = WaitForSingleObject(ngx_cache_manager_event, (u_long) next);

    if (ev != WAIT_TIMEOUT) {

        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0,
                       "cache manager WaitForSingleObject: %ul", ev);
    }
}


static ngx_thread_value_t __stdcall
ngx_cache_loader_thread(void *data)
{
    ngx_uint_t     i;
    ngx_path_t   **path;
    ngx_cycle_t   *cycle;

    ngx_msleep(60000);

    cycle = (ngx_cycle_t *) ngx_cycle;

    path = cycle->paths.elts;
    for (i = 0; i < cycle->paths.nelts; i++) {

        if (ngx_terminate || ngx_quit || ngx_exiting) {
            break;
        }

        if (path[i]->loader) {
            path[i]->loader(path[i]->data);
            ngx_time_update();
        }
    }

    return 0;
}


void
ngx_single_process_cycle(ngx_cycle_t *cycle)
{
    ngx_tid_t  tid;

    ngx_console_init(cycle);

    if (ngx_create_signal_events(cycle) != NGX_OK) {
        exit(2);
    }

    if (ngx_create_thread(&tid, ngx_worker_thread, NULL, cycle->log) != 0) {
        /* fatal */
        exit(2);
    }

    /* STUB */
    WaitForSingleObject(ngx_stop_event, INFINITE);
}


ngx_int_t
ngx_os_signal_process(ngx_cycle_t *cycle, char *sig, ngx_pid_t pid)
{
    HANDLE     ev;
    ngx_int_t  rc;
    char       evn[NGX_PROCESS_SYNC_NAME];

    ngx_sprintf((u_char *) evn, "Global\\ngx_%s_%P%Z", sig, pid);

    ev = OpenEvent(EVENT_MODIFY_STATE, 0, evn);
    if (ev == NULL) {
        ngx_log_error(NGX_LOG_ERR, cycle->log, ngx_errno,
                      "OpenEvent(\"%s\") failed", evn);
        return 1;
    }

    if (SetEvent(ev) == 0) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "SetEvent(\"%s\") failed", evn);
        rc = 1;

    } else {
        rc = 0;
    }

    ngx_close_handle(ev);

    return rc;
}


void
ngx_close_handle(HANDLE h)
{
    if (CloseHandle(h) == 0) {
        ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_errno,
                      "CloseHandle(%p) failed", h);
    }
}