Initial version.

1 files changed, 1743 insertions, 0 deletions

diff --git a/src/nxt_cycle.c b/src/nxt_cycle.c
new file mode 100644
index 00000000..8539bc05
--- /dev/null
+++ b/src/nxt_cycle.c
@@ -0,0 +1,1743 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ * Copyright (C) Valentin V. Bartenev
+ * Copyright (C) NGINX, Inc.
+ */
+
+#include <nxt_main.h>
+#include <nxt_cycle.h>
+#include <nxt_process_chan.h>
+#include <nxt_master_process.h>
+
+
+static nxt_int_t nxt_cycle_inherited_listen_sockets(nxt_thread_t *thr,
+    nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_systemd_listen_sockets(nxt_thread_t *thr,
+    nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_event_engines(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_processes(nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_thread_pools(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static void nxt_cycle_start(nxt_thread_t *thr, void *obj, void *data);
+static void nxt_cycle_initial_start(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static void nxt_cycle_conf_test(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static void nxt_single_process_start(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static void nxt_cycle_close_idle_connections(nxt_thread_t *thr);
+static void nxt_cycle_exit(nxt_thread_t *thr, void *obj, void *data);
+static nxt_int_t nxt_cycle_event_engine_change(nxt_thread_t *thr,
+    nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_conf_init(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_conf_read_cmd(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static nxt_sockaddr_t *nxt_cycle_sockaddr_parse(nxt_str_t *addr,
+    nxt_mem_pool_t *mp, nxt_log_t *log);
+static nxt_sockaddr_t *nxt_cycle_sockaddr_unix_parse(nxt_str_t *addr,
+    nxt_mem_pool_t *mp, nxt_log_t *log);
+static nxt_sockaddr_t *nxt_cycle_sockaddr_inet6_parse(nxt_str_t *addr,
+    nxt_mem_pool_t *mp, nxt_log_t *log);
+static nxt_sockaddr_t *nxt_cycle_sockaddr_inet_parse(nxt_str_t *addr,
+    nxt_mem_pool_t *mp, nxt_log_t *log);
+static nxt_int_t nxt_cycle_conf_apply(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_listen_socket(nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_hostname(nxt_thread_t *thr, nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_log_files_init(nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_log_files_create(nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_listen_sockets_create(nxt_cycle_t *cycle);
+static void nxt_cycle_listen_sockets_close(nxt_cycle_t *cycle);
+static void nxt_cycle_pid_file_delete(nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_shm_zones_enable(nxt_cycle_t *cycle);
+static nxt_int_t nxt_cycle_shm_zone_create(nxt_cycle_shm_zone_t *shm_zone);
+
+#if (NXT_THREADS)
+static void nxt_cycle_thread_pool_destroy(nxt_thread_t *thr,
+    nxt_cycle_t *cycle, nxt_cycle_cont_t cont);
+#endif
+
+
+nxt_thread_declare_data(nxt_cycle_t *, nxt_thread_cycle_data);
+
+
+nxt_int_t
+nxt_cycle_create(nxt_thread_t *thr, nxt_cycle_t *previous,
+    nxt_cycle_cont_t start, nxt_str_t *config_name, nxt_bool_t test_config)
+{
+    nxt_int_t           ret;
+    nxt_cycle_t         *cycle;
+    nxt_array_t         *listen_sockets;
+    nxt_mem_pool_t      *mp;
+    static nxt_str_t    upstream_zone = nxt_string("upstream_zone");
+
+    mp = nxt_mem_pool_create(1024);
+
+    if (nxt_slow_path(mp == NULL)) {
+        return NXT_ERROR;
+    }
+
+    /* This alloction cannot fail. */
+    cycle = nxt_mem_zalloc(mp, sizeof(nxt_cycle_t));
+
+    cycle->mem_pool = mp;
+    cycle->previous = previous;
+    cycle->config_name = config_name;
+    cycle->test_config = test_config;
+
+    if (previous == NULL) {
+        cycle->prefix = nxt_current_directory(mp);
+
+    } else {
+        cycle->type = previous->type;
+        cycle->prefix = nxt_str_dup(mp, NULL, previous->prefix);
+    }
+
+    if (nxt_slow_path(cycle->prefix == NULL)) {
+        goto fail;
+    }
+
+    cycle->conf_prefix = cycle->prefix;
+
+    cycle->services = nxt_services_init(mp);
+    if (nxt_slow_path(cycle->services == NULL)) {
+        goto fail;
+    }
+
+    listen_sockets = nxt_array_create(mp, 1, sizeof(nxt_listen_socket_t));
+    if (nxt_slow_path(listen_sockets == NULL)) {
+        goto fail;
+    }
+
+    cycle->listen_sockets = listen_sockets;
+
+    if (previous == NULL) {
+        ret = nxt_cycle_inherited_listen_sockets(thr, cycle);
+        if (nxt_slow_path(ret != NXT_OK)) {
+            goto fail;
+        }
+    }
+
+    if (nxt_slow_path(nxt_cycle_hostname(thr, cycle) != NXT_OK)) {
+        goto fail;
+    }
+
+    if (nxt_slow_path(nxt_cycle_log_files_init(cycle) != NXT_OK)) {
+        goto fail;
+    }
+
+    if (nxt_slow_path(nxt_cycle_event_engines(thr, cycle) != NXT_OK)) {
+        goto fail;
+    }
+
+    if (nxt_slow_path(nxt_cycle_processes(cycle) != NXT_OK)) {
+        goto fail;
+    }
+
+    if (nxt_slow_path(nxt_cycle_thread_pools(thr, cycle) != NXT_OK)) {
+        goto fail;
+    }
+
+    ret = nxt_cycle_shm_zone_add(cycle, &upstream_zone, 1024 * 1024, 8192);
+    if (nxt_slow_path(ret != NXT_OK)) {
+        goto fail;
+    }
+
+    /* Cycle shm zones array is created on demand. */
+
+    if (previous != NULL) {
+        previous->reconfiguring = 1;
+        cycle->start = start;
+
+    } else {
+        nxt_thread_init_data(nxt_thread_cycle_data);
+        nxt_thread_cycle_set(cycle);
+
+        cycle->start = test_config ? nxt_cycle_conf_test:
+                                     nxt_cycle_initial_start;
+    }
+
+    nxt_log_debug(thr->log, "new cycle: %p", cycle);
+
+    nxt_thread_work_queue_add(thr, &thr->work_queue.main, nxt_cycle_start,
+                              cycle, NULL, &nxt_main_log);
+
+    return NXT_OK;
+
+fail:
+
+    nxt_mem_pool_destroy(mp);
+
+    return NXT_ERROR;
+}
+
+
+static nxt_int_t
+nxt_cycle_inherited_listen_sockets(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    u_char               *v, *p;
+    nxt_int_t            type;
+    nxt_array_t          *inherited_sockets;
+    nxt_socket_t         s;
+    nxt_listen_socket_t  *ls;
+
+    v = (u_char *) getenv("NGINX");
+
+    if (v == NULL) {
+        return nxt_cycle_systemd_listen_sockets(thr, cycle);
+    }
+
+    nxt_log_error(NXT_LOG_NOTICE, thr->log,
+                  "using inherited listen sockets: %s", v);
+
+    inherited_sockets = nxt_array_create(cycle->mem_pool,
+                                         1, sizeof(nxt_listen_socket_t));
+    if (inherited_sockets == NULL) {
+        return NXT_ERROR;
+    }
+
+    cycle->inherited_sockets = inherited_sockets;
+
+    for (p = v; *p != '\0'; p++) {
+
+        if (*p == ';') {
+            s = nxt_int_parse(v, p - v);
+
+            if (nxt_slow_path(s < 0)) {
+                nxt_log_emerg(thr->log, "invalid socket number "
+                              "\"%s\" in NGINX environment variable, "
+                              "ignoring the rest of the variable", v);
+                return NXT_ERROR;
+            }
+
+            v = p + 1;
+
+            ls = nxt_array_zero_add(inherited_sockets);
+            if (nxt_slow_path(ls == NULL)) {
+                return NXT_ERROR;
+            }
+
+            ls->socket = s;
+
+            ls->sockaddr = nxt_getsockname(cycle->mem_pool, s);
+            if (nxt_slow_path(ls->sockaddr == NULL)) {
+                return NXT_ERROR;
+            }
+
+            type = nxt_socket_getsockopt(s, SOL_SOCKET, SO_TYPE);
+            if (nxt_slow_path(type == -1)) {
+                return NXT_ERROR;
+            }
+
+            ls->sockaddr->type = (uint16_t) type;
+        }
+    }
+
+    return NXT_OK;
+}
+
+
+static nxt_int_t
+nxt_cycle_systemd_listen_sockets(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    u_char               *nfd, *pid;
+    nxt_int_t            n;
+    nxt_array_t          *inherited_sockets;
+    nxt_socket_t         s;
+    nxt_listen_socket_t  *ls;
+
+    /*
+     * Number of listening sockets passed.  The socket
+     * descriptors start from number 3 and are sequential.
+     */
+    nfd = (u_char *) getenv("LISTEN_FDS");
+    if (nfd == NULL) {
+        return NXT_OK;
+    }
+
+    /* The pid of the service process. */
+    pid = (u_char *) getenv("LISTEN_PID");
+    if (pid == NULL) {
+        return NXT_OK;
+    }
+
+    n = nxt_int_parse(nfd, nxt_strlen(nfd));
+    if (n < 0) {
+        return NXT_OK;
+    }
+
+    if (nxt_pid != nxt_int_parse(pid, nxt_strlen(pid))) {
+        return NXT_OK;
+    }
+
+    nxt_log_error(NXT_LOG_NOTICE, thr->log,
+                  "using %s systemd listen sockets", n);
+
+    inherited_sockets = nxt_array_create(cycle->mem_pool,
+                                         n, sizeof(nxt_listen_socket_t));
+    if (inherited_sockets == NULL) {
+        return NXT_ERROR;
+    }
+
+    cycle->inherited_sockets = inherited_sockets;
+
+    for (s = 3; s < n; s++) {
+        ls = nxt_array_zero_add(inherited_sockets);
+        if (nxt_slow_path(ls == NULL)) {
+            return NXT_ERROR;
+        }
+
+        ls->socket = s;
+
+        ls->sockaddr = nxt_getsockname(cycle->mem_pool, s);
+        if (nxt_slow_path(ls->sockaddr == NULL)) {
+            return NXT_ERROR;
+        }
+
+        ls->sockaddr->type = SOCK_STREAM;
+    }
+
+    return NXT_OK;
+}
+
+
+static nxt_int_t
+nxt_cycle_event_engines(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    nxt_event_engine_t         *engine, **e, **engines;
+    const nxt_event_set_ops_t  *event_set;
+
+    cycle->engines = nxt_array_create(cycle->mem_pool, 1,
+                                      sizeof(nxt_event_engine_t *));
+
+    if (nxt_slow_path(cycle->engines == NULL)) {
+        return NXT_ERROR;
+    }
+
+    e = nxt_array_add(cycle->engines);
+    if (nxt_slow_path(e == NULL)) {
+        return NXT_ERROR;
+    }
+
+    if (cycle->previous != NULL) {
+        /* Event engines are not allocated in memory pool. */
+        engines = cycle->previous->engines->elts;
+        *e = engines[0];
+
+    } else {
+        event_set = nxt_service_get(cycle->services, "engine", NULL);
+
+        if (nxt_slow_path(event_set == NULL)) {
+            /* TODO: log */
+            return NXT_ERROR;
+        }
+
+        engine = nxt_event_engine_create(thr, event_set,
+                                         nxt_master_process_signals, 0, 0);
+
+        if (nxt_slow_path(engine == NULL)) {
+            return NXT_ERROR;
+        }
+
+        engine->id = cycle->last_engine_id++;
+        *e = engine;
+    }
+
+    return NXT_OK;
+}
+
+
+static nxt_int_t
+nxt_cycle_processes(nxt_cycle_t *cycle)
+{
+    nxt_uint_t          n;
+    nxt_process_chan_t  *proc, *prev;
+
+    /*
+     * Preallocate double number of previous cycle
+     * process slots or 2 process slots for initial cycle.
+     */
+    n = (cycle->previous != NULL) ? cycle->previous->processes->nelts : 1;
+
+    cycle->processes = nxt_array_create(cycle->mem_pool, 2 * n,
+                                        sizeof(nxt_process_chan_t));
+
+    if (nxt_slow_path(cycle->processes == NULL)) {
+        return NXT_ERROR;
+    }
+
+    if (cycle->previous != NULL) {
+        cycle->process_generation = cycle->previous->process_generation;
+
+        prev = cycle->previous->processes->elts;
+
+        while (n != 0) {
+            proc = nxt_array_add(cycle->processes);
+            if (nxt_slow_path(proc == NULL)) {
+                return NXT_ERROR;
+            }
+
+            *proc = *prev++;
+            n--;
+        }
+    }
+
+    return NXT_OK;
+}
+
+
+static nxt_int_t
+nxt_cycle_thread_pools(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+#if (NXT_THREADS)
+    nxt_int_t    ret;
+    nxt_array_t  *thread_pools;
+
+    thread_pools = nxt_array_create(cycle->mem_pool, 1,
+                                    sizeof(nxt_thread_pool_t *));
+
+    if (nxt_slow_path(thread_pools == NULL)) {
+        return NXT_ERROR;
+    }
+
+    cycle->thread_pools = thread_pools;
+
+    ret = nxt_cycle_thread_pool_create(thr, cycle, 2, 60000 * 1000000LL);
+
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NXT_ERROR;
+    }
+
+#endif
+
+    return NXT_OK;
+}
+
+
+static void
+nxt_cycle_start(nxt_thread_t *thr, void *obj, void *data)
+{
+    nxt_uint_t   i;
+    nxt_cycle_t  *cycle;
+
+    cycle = obj;
+
+    nxt_log_debug(thr->log, "cycle conf done");
+
+    nxt_mem_pool_debug_lock(cycle->mem_pool, nxt_thread_tid(thr));
+
+    thr->log->ctx_handler = NULL;
+    thr->log->ctx = NULL;
+
+    if (nxt_cycle_conf_init(thr, cycle) != NXT_OK) {
+        goto fail;
+    }
+
+    for (i = 0; i < nxt_init_modules_n; i++) {
+        if (nxt_init_modules[i](thr, cycle) != NXT_OK) {
+            goto fail;
+        }
+    }
+
+    if (nxt_cycle_conf_apply(thr, cycle) != NXT_OK) {
+        goto fail;
+    }
+
+    nxt_thread_cycle_set(cycle);
+
+#if (NXT_THREADS)
+
+    /*
+     * Thread pools should be destroyed before starting worker
+     * processes, because thread pool semaphores will stick in
+     * locked state in new processes after fork().
+     */
+    nxt_cycle_thread_pool_destroy(thr, cycle, cycle->start);
+
+#else
+
+    cycle->start(thr, cycle);
+
+#endif
+
+    return;
+
+fail:
+
+    nxt_cycle_quit(thr, cycle);
+}
+
+
+static void
+nxt_cycle_initial_start(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    nxt_int_t                  ret;
+    const nxt_event_set_ops_t  *event_set;
+
+    if (cycle->inherited_sockets == NULL && cycle->daemon) {
+
+        if (nxt_process_daemon() != NXT_OK) {
+            goto fail;
+        }
+
+        /*
+         * An event engine should be updated after fork()
+         * even if an event facility was not changed because:
+         * 1) inherited kqueue descriptor is invalid,
+         * 2) the signal thread is not inherited.
+         */
+        event_set = nxt_service_get(cycle->services, "engine", cycle->engine);
+        if (event_set == NULL) {
+            goto fail;
+        }
+
+        ret = nxt_event_engine_change(thr, event_set, cycle->batch);
+        if (ret != NXT_OK) {
+            goto fail;
+        }
+    }
+
+    ret = nxt_cycle_pid_file_create(cycle->pid_file, cycle->test_config);
+    if (ret != NXT_OK) {
+        goto fail;
+    }
+
+    if (nxt_cycle_event_engine_change(thr, cycle) != NXT_OK) {
+        goto fail;
+    }
+
+    thr->engine->max_connections = cycle->engine_connections;
+
+    if (cycle->master_process) {
+        if (nxt_master_process_start(thr, cycle) != NXT_ERROR) {
+            return;
+        }
+
+    } else {
+        nxt_single_process_start(thr, cycle);
+        return;
+    }
+
+fail:
+
+    nxt_cycle_quit(thr, cycle);
+}
+
+
+static void
+nxt_cycle_conf_test(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    (void) nxt_cycle_pid_file_create(cycle->pid_file, cycle->test_config);
+
+    nxt_cycle_quit(thr, cycle);
+}
+
+
+static void
+nxt_single_process_start(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+#if (NXT_THREADS)
+    nxt_int_t  ret;
+
+    ret = nxt_cycle_thread_pool_create(thr, cycle, cycle->auxiliary_threads,
+                                       60000 * 1000000LL);
+
+    if (nxt_slow_path(ret != NXT_OK)) {
+        nxt_cycle_quit(thr, cycle);
+        return;
+    }
+
+#endif
+
+    cycle->type = NXT_PROCESS_SINGLE;
+
+    nxt_cycle_listen_sockets_enable(thr, cycle);
+
+    return;
+}
+
+
+void
+nxt_cycle_quit(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    nxt_bool_t   done;
+
+    nxt_log_debug(thr->log, "exiting");
+
+    if (cycle == NULL) {
+        cycle = nxt_thread_cycle();
+    }
+
+    done = 1;
+
+    if (!thr->engine->shutdown) {
+        thr->engine->shutdown = 1;
+
+#if (NXT_THREADS)
+
+        if (!nxt_array_is_empty(cycle->thread_pools)) {
+            nxt_cycle_thread_pool_destroy(thr, cycle, nxt_cycle_quit);
+            done = 0;
+        }
+
+#endif
+
+        if (!cycle->test_config && cycle->type == NXT_PROCESS_MASTER) {
+            nxt_master_stop_worker_processes(cycle);
+            done = 0;
+        }
+    }
+
+    nxt_cycle_close_idle_connections(thr);
+
+    if (done) {
+        nxt_thread_work_queue_add(thr, &thr->work_queue.main, nxt_cycle_exit,
+                                  cycle, NULL, &nxt_main_log);
+    }
+}
+
+
+static void
+nxt_cycle_close_idle_connections(nxt_thread_t *thr)
+{
+    nxt_queue_t       *idle;
+    nxt_queue_link_t  *link, *next;
+    nxt_event_conn_t  *c;
+
+    nxt_log_debug(thr->log, "close idle connections");
+
+    idle = &thr->engine->idle_connections;
+
+    for (link = nxt_queue_head(idle);
+         link != nxt_queue_tail(idle);
+         link = next)
+    {
+        next = nxt_queue_next(link);
+        c = nxt_queue_link_data(link, nxt_event_conn_t, link);
+
+        if (!c->socket.read_ready) {
+            nxt_queue_remove(link);
+            nxt_event_conn_close(thr, c);
+        }
+    }
+}
+
+
+static void
+nxt_cycle_exit(nxt_thread_t *thr, void *obj, void *data)
+{
+    nxt_cycle_t  *cycle;
+
+    cycle = obj;
+
+#if (NXT_THREADS)
+
+    nxt_log_debug(thr->log, "thread pools: %d", cycle->thread_pools->nelts);
+
+    if (!nxt_array_is_empty(cycle->thread_pools)) {
+        return;
+    }
+
+#endif
+
+    if (cycle->type <= NXT_PROCESS_MASTER) {
+        nxt_cycle_pid_file_delete(cycle);
+    }
+
+    if (!thr->engine->event->signal_support) {
+        nxt_event_engine_signals_stop(thr->engine);
+    }
+
+    nxt_log_debug(thr->log, "exit");
+
+    exit(0);
+    nxt_unreachable();
+}
+
+
+static nxt_int_t
+nxt_cycle_event_engine_change(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    const nxt_event_set_ops_t  *event_set;
+
+    if (thr->engine->batch == cycle->batch
+        && nxt_strcmp(thr->engine->event->name, cycle->engine) == 0)
+    {
+        return NXT_OK;
+    }
+
+    event_set = nxt_service_get(cycle->services, "engine", cycle->engine);
+    if (event_set != NULL) {
+        return nxt_event_engine_change(thr, event_set, cycle->batch);
+    }
+
+    return NXT_ERROR;
+}
+
+
+void
+nxt_cycle_event_engine_free(nxt_cycle_t *cycle)
+{
+    nxt_event_engine_t      *engine, **engines;
+
+    engines = cycle->engines->elts;
+    engine = engines[0];
+    nxt_array_remove(cycle->engines, &engines[0]);
+
+    nxt_event_engine_free(engine);
+}
+
+
+#if (NXT_THREADS)
+
+static void nxt_cycle_thread_pool_init(void);
+static void nxt_cycle_thread_pool_exit(nxt_thread_t *thr, void *obj,
+    void *data);
+
+
+nxt_int_t
+nxt_cycle_thread_pool_create(nxt_thread_t *thr, nxt_cycle_t *cycle,
+    nxt_uint_t max_threads, nxt_nsec_t timeout)
+{
+    nxt_thread_pool_t   *thread_pool, **tp;
+
+    tp = nxt_array_add(cycle->thread_pools);
+    if (tp == NULL) {
+        return NXT_ERROR;
+    }
+
+    thread_pool = nxt_thread_pool_create(max_threads, timeout,
+                                         nxt_cycle_thread_pool_init,
+                                         thr->engine,
+                                         nxt_cycle_thread_pool_exit);
+
+    if (nxt_fast_path(thread_pool != NULL)) {
+        *tp = thread_pool;
+    }
+
+    return NXT_OK;
+}
+
+
+static void
+nxt_cycle_thread_pool_destroy(nxt_thread_t *thr, nxt_cycle_t *cycle,
+    nxt_cycle_cont_t cont)
+{
+    nxt_uint_t         n;
+    nxt_thread_pool_t  **tp;
+
+    cycle->continuation = cont;
+
+    n = cycle->thread_pools->nelts;
+
+    if (n == 0) {
+        cont(thr, cycle);
+        return;
+    }
+
+    tp = cycle->thread_pools->elts;
+
+    do {
+        nxt_thread_pool_destroy(*tp);
+
+        tp++;
+        n--;
+    } while (n != 0);
+}
+
+
+static void
+nxt_cycle_thread_pool_init(void)
+{
+#if (NXT_REGEX)
+    nxt_regex_init(0);
+#endif
+}
+
+
+static void
+nxt_cycle_thread_pool_exit(nxt_thread_t *thr, void *obj, void *data)
+{
+    nxt_uint_t           i, n;
+    nxt_cycle_t          *cycle;
+    nxt_thread_pool_t    *tp, **thread_pools;
+    nxt_thread_handle_t  handle;
+
+    tp = obj;
+
+    if (data != NULL) {
+        handle = (nxt_thread_handle_t) (uintptr_t) data;
+        nxt_thread_wait(handle);
+    }
+
+    cycle = nxt_thread_cycle();
+
+    thread_pools = cycle->thread_pools->elts;
+    n = cycle->thread_pools->nelts;
+
+    nxt_log_debug(thr->log, "thread pools: %ui, cycle %p", n, cycle);
+
+    for (i = 0; i < n; i++) {
+
+        if (tp == thread_pools[i]) {
+            nxt_array_remove(cycle->thread_pools, &thread_pools[i]);
+
+            if (n == 1) {
+                /* The last thread pool. */
+                cycle->continuation(thr, cycle);
+            }
+
+            return;
+        }
+    }
+}
+
+#endif
+
+
+static nxt_int_t
+nxt_cycle_conf_init(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    nxt_int_t                  ret;
+    nxt_str_t                  *prefix;
+    nxt_file_t                 *file;
+    nxt_file_name_str_t        file_name;
+    const nxt_event_set_ops_t  *event_set;
+
+    cycle->daemon = 1;
+    cycle->master_process = 1;
+    cycle->engine_connections = 256;
+    cycle->worker_processes = 1;
+    cycle->auxiliary_threads = 2;
+    cycle->user_cred.user = "nobody";
+    cycle->group = NULL;
+    cycle->pid = "nginman.pid";
+    cycle->error_log = "error.log";
+
+    if (nxt_cycle_conf_read_cmd(thr, cycle) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    if (nxt_user_cred_get(&cycle->user_cred, cycle->group) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    /* An engine's parameters. */
+
+    event_set = nxt_service_get(cycle->services, "engine", cycle->engine);
+    if (event_set == NULL) {
+        return NXT_ERROR;
+    }
+
+    cycle->engine = event_set->name;
+
+    prefix = nxt_file_name_is_absolute(cycle->pid) ? NULL : cycle->prefix;
+
+    ret = nxt_file_name_create(cycle->mem_pool, &file_name, "%V%s%Z",
+                               prefix, cycle->pid);
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NXT_ERROR;
+    }
+
+    cycle->pid_file = file_name.start;
+
+    prefix = nxt_file_name_is_absolute(cycle->error_log) ? NULL : cycle->prefix;
+
+    ret = nxt_file_name_create(cycle->mem_pool, &file_name, "%V%s%Z",
+                               prefix, cycle->error_log);
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NXT_ERROR;
+    }
+
+    file = nxt_list_first(cycle->log_files);
+    file->name = file_name.start;
+
+    return NXT_OK;
+}
+
+
+static nxt_int_t
+nxt_cycle_conf_read_cmd(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    char            *p, **argv;
+    nxt_int_t       n;
+    nxt_str_t       addr;
+    nxt_sockaddr_t  *sa;
+
+    argv = nxt_process_argv;
+
+    while (*argv != NULL) {
+        p = *argv++;
+
+        if (nxt_strcmp(p, "--listen") == 0) {
+            if (*argv == NULL) {
+                nxt_log_emerg(thr->log, "no argument for option \"--listen\"");
+                return NXT_ERROR;
+            }
+
+            p = *argv++;
+
+            addr.len = nxt_strlen(p);
+            addr.data = (u_char *) p;
+
+            sa = nxt_cycle_sockaddr_parse(&addr, cycle->mem_pool, thr->log);
+
+            if (sa == NULL) {
+                return NXT_ERROR;
+            }
+
+            cycle->listen = sa;
+
+            continue;
+        }
+
+        if (nxt_strcmp(p, "--workers") == 0) {
+            if (*argv == NULL) {
+                nxt_log_emerg(thr->log, "no argument for option \"--workers\"");
+                return NXT_ERROR;
+            }
+
+            p = *argv++;
+            n = nxt_int_parse((u_char *) p, nxt_strlen(p));
+
+            if (n < 1) {
+                nxt_log_emerg(thr->log, "invalid number of workers: \"%s\"", p);
+                return NXT_ERROR;
+            }
+
+            cycle->worker_processes = n;
+
+            continue;
+        }
+
+        if (nxt_strcmp(p, "--user") == 0) {
+            if (*argv == NULL) {
+                nxt_log_emerg(thr->log, "no argument for option \"--user\"");
+                return NXT_ERROR;
+            }
+
+            p = *argv++;
+
+            cycle->user_cred.user = p;
+
+            continue;
+        }
+
+        if (nxt_strcmp(p, "--group") == 0) {
+            if (*argv == NULL) {
+                nxt_log_emerg(thr->log, "no argument for option \"--group\"");
+                return NXT_ERROR;
+            }
+
+            p = *argv++;
+
+            cycle->group = p;
+
+            continue;
+        }
+
+        if (nxt_strcmp(p, "--pid") == 0) {
+            if (*argv == NULL) {
+                nxt_log_emerg(thr->log, "no argument for option \"--pid\"");
+                return NXT_ERROR;
+            }
+
+            p = *argv++;
+
+            cycle->pid = p;
+
+            continue;
+        }
+
+        if (nxt_strcmp(p, "--log") == 0) {
+            if (*argv == NULL) {
+                nxt_log_emerg(thr->log, "no argument for option \"--log\"");
+                return NXT_ERROR;
+            }
+
+            p = *argv++;
+
+            cycle->error_log = p;
+
+            continue;
+        }
+
+        if (nxt_strcmp(p, "--no-daemonize") == 0) {
+            cycle->daemon = 0;
+            continue;
+        }
+    }
+
+    return NXT_OK;
+}
+
+
+static nxt_sockaddr_t *
+nxt_cycle_sockaddr_parse(nxt_str_t *addr, nxt_mem_pool_t *mp, nxt_log_t *log)
+{
+    u_char  *p;
+    size_t  len;
+
+    len = addr->len;
+    p = addr->data;
+
+    if (len >= 5 && nxt_memcmp(p, (u_char *) "unix:", 5) == 0) {
+        return nxt_cycle_sockaddr_unix_parse(addr, mp, log);
+    }
+
+    if (len != 0 && *p == '[') {
+        return nxt_cycle_sockaddr_inet6_parse(addr, mp, log);
+    }
+
+    return nxt_cycle_sockaddr_inet_parse(addr, mp, log);
+}
+
+
+static nxt_sockaddr_t *
+nxt_cycle_sockaddr_unix_parse(nxt_str_t *addr, nxt_mem_pool_t *mp,
+    nxt_log_t *log)
+{
+#if (NXT_HAVE_UNIX_DOMAIN)
+    u_char          *p;
+    size_t          len, socklen;
+    nxt_sockaddr_t  *sa;
+
+    /*
+     * Actual sockaddr_un length can be lesser or even larger than defined
+     * struct sockaddr_un length (see comment in unix/nxt_socket.h).  So
+     * limit maximum Unix domain socket address length by defined sun_path[]
+     * length because some OSes accept addresses twice larger than defined
+     * struct sockaddr_un.  Also reserve space for a trailing zero to avoid
+     * ambiguity, since many OSes accept Unix domain socket addresses
+     * without a trailing zero.
+     */
+    const size_t max_len = sizeof(struct sockaddr_un)
+                           - offsetof(struct sockaddr_un, sun_path) - 1;
+
+    /* cutting "unix:" */
+    len = addr->len - 5;
+    p = addr->data + 5;
+
+    if (len == 0) {
+        nxt_log_emerg(log, "unix domain socket \"%V\" name is invalid", addr);
+        return NULL;
+    }
+
+    if (len > max_len) {
+        nxt_log_emerg(log, "unix domain socket \"%V\" name is too long", addr);
+        return NULL;
+    }
+
+    socklen = offsetof(struct sockaddr_un, sun_path) + len + 1;
+
+#if (NXT_LINUX)
+
+    /*
+     * Linux unix(7):
+     *
+     *   abstract: an abstract socket address is distinguished by the fact
+     *   that sun_path[0] is a null byte ('\0').  The socket's address in
+     *   this namespace is given by the additional bytes in sun_path that
+     *   are covered by the specified length of the address structure.
+     *   (Null bytes in the name have no special significance.)
+     */
+    if (p[0] == '@') {
+        p[0] = '\0';
+        socklen--;
+    }
+
+#endif
+
+    sa = nxt_sockaddr_alloc(mp, socklen);
+
+    if (nxt_slow_path(sa == NULL)) {
+        return NULL;
+    }
+
+    sa->type = SOCK_STREAM;
+
+    sa->u.sockaddr_un.sun_family = AF_UNIX;
+    nxt_memcpy(sa->u.sockaddr_un.sun_path, p, len);
+
+    return sa;
+
+#else  /* !(NXT_HAVE_UNIX_DOMAIN) */
+
+    nxt_log_emerg(log, "unix domain socket \"%V\" is not supported", addr);
+
+    return NULL;
+
+#endif
+}
+
+
+static nxt_sockaddr_t *
+nxt_cycle_sockaddr_inet6_parse(nxt_str_t *addr, nxt_mem_pool_t *mp,
+    nxt_log_t *log)
+{
+#if (NXT_INET6)
+    u_char           *p, *addr, *addr_end;
+    size_t           len;
+    nxt_int_t        port;
+    nxt_mem_pool_t   *mp;
+    nxt_sockaddr_t   *sa;
+    struct in6_addr  *in6_addr;
+
+    len = addr->len - 1;
+    p = addr->data + 1;
+
+    addr_end = nxt_memchr(p, ']', len);
+
+    if (addr_end == NULL) {
+        goto invalid_address;
+    }
+
+    sa = nxt_sockaddr_alloc(mp, sizeof(struct sockaddr_in6));
+
+    if (nxt_slow_path(sa == NULL)) {
+        return NULL;
+    }
+
+    in6_addr = &sa->u.sockaddr_in6.sin6_addr;
+
+    if (nxt_inet6_addr(in6_addr, p, addr_end - p) != NXT_OK) {
+        goto invalid_address;
+    }
+
+    p = addr_end + 1;
+    len = (p + len) - p;
+
+    if (len == 0) {
+        goto found;
+    }
+
+    if (*p == ':') {
+        port = nxt_int_parse(p + 1, len - 1);
+
+        if (port >= 1 && port <= 65535) {
+            goto found;
+        }
+    }
+
+    nxt_log_emerg(log, "invalid port in \"%V\"", addr);
+
+    return NULL;
+
+found:
+
+    sa->type = SOCK_STREAM;
+
+    sa->u.sockaddr_in6.sin6_family = AF_INET6;
+    sa->u.sockaddr_in6.sin6_port = htons((in_port_t) port);
+
+    return sa;
+
+invalid_address:
+
+    nxt_log_emerg(log, "invalid IPv6 address in \"%V\"", addr);
+
+    return NULL;
+
+#else
+
+    nxt_log_emerg(log, "IPv6 socket \"%V\" is not supported", addr);
+
+    return NULL;
+
+#endif
+}
+
+
+static nxt_sockaddr_t *
+nxt_cycle_sockaddr_inet_parse(nxt_str_t *addr, nxt_mem_pool_t *mp,
+    nxt_log_t *log)
+{
+    u_char          *p, *ip;
+    size_t          len;
+    in_addr_t       s_addr;
+    nxt_int_t       port;
+    nxt_sockaddr_t  *sa;
+
+    s_addr = INADDR_ANY;
+
+    len = addr->len;
+    ip = addr->data;
+
+    p = nxt_memchr(ip, ':', len);
+
+    if (p == NULL) {
+
+        /* single value port, or address */
+
+        port = nxt_int_parse(ip, len);
+
+        if (port > 0) {
+            /* "*:XX" */
+
+            if (port < 1 || port > 65535) {
+                goto invalid_port;
+            }
+
+        } else {
+            /* "x.x.x.x" */
+
+            s_addr = nxt_inet_addr(ip, len);
+
+            if (s_addr == INADDR_NONE) {
+                goto invalid_port;
+            }
+
+            port = 8080;
+        }
+
+    } else {
+
+        /* x.x.x.x:XX */
+
+        p++;
+        len = (ip + len) - p;
+        port = nxt_int_parse(p, len);
+
+        if (port < 1 || port > 65535) {
+            goto invalid_port;
+        }
+
+        len = (p - 1) - ip;
+
+        if (len != 1 || ip[0] != '*') {
+            s_addr = nxt_inet_addr(ip, len);
+
+            if (s_addr == INADDR_NONE) {
+                goto invalid_addr;
+            }
+
+            /* "x.x.x.x:XX" */
+        }
+    }
+
+    sa = nxt_sockaddr_alloc(mp, sizeof(struct sockaddr_in));
+
+    if (nxt_slow_path(sa == NULL)) {
+        return NULL;
+    }
+
+    sa->type = SOCK_STREAM;
+
+    sa->u.sockaddr_in.sin_family = AF_INET;
+    sa->u.sockaddr_in.sin_port = htons((in_port_t) port);
+    sa->u.sockaddr_in.sin_addr.s_addr = s_addr;
+
+    return sa;
+
+invalid_port:
+
+    nxt_log_emerg(log, "invalid port in \"%V\"", addr);
+
+    return NULL;
+
+invalid_addr:
+
+    nxt_log_emerg(log, "invalid address in \"%V\"", addr);
+
+    return NULL;
+}
+
+
+static nxt_int_t
+nxt_cycle_conf_apply(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    if (nxt_cycle_log_files_create(cycle) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    if (nxt_cycle_listen_socket(cycle) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    if (nxt_cycle_event_engine_change(thr, cycle) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    if (nxt_cycle_listen_sockets_create(cycle) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    if (nxt_cycle_shm_zones_enable(cycle) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    nxt_cycle_listen_sockets_close(cycle);
+
+    return NXT_OK;
+}
+
+
+static nxt_int_t
+nxt_cycle_listen_socket(nxt_cycle_t *cycle)
+{
+    nxt_sockaddr_t       *sa;
+//    nxt_work_queue_t     *wq;
+    nxt_listen_socket_t  *ls;
+
+    if (cycle->listen == NULL) {
+        sa = nxt_sockaddr_alloc(cycle->mem_pool, sizeof(struct sockaddr_in));
+        if (sa == NULL) {
+            return NXT_ERROR;
+        }
+
+        sa->type = SOCK_STREAM;
+        sa->u.sockaddr_in.sin_family = AF_INET;
+        sa->u.sockaddr_in.sin_port = htons(8080);
+
+        cycle->listen = sa;
+    }
+
+    if (nxt_sockaddr_text(cycle->mem_pool, cycle->listen, 1) != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    ls = nxt_cycle_listen_socket_add(cycle, cycle->listen);
+    if (ls == NULL) {
+        return NXT_ERROR;
+    }
+
+    ls->read_after_accept = 1;
+
+#if 0
+    ls->flags = NXT_NONBLOCK;
+
+    /* STUB */
+    wq = nxt_mem_zalloc(cf->mem_pool, sizeof(nxt_work_queue_t));
+    if (wq == NULL) {
+        return NXT_ERROR;
+    }
+    nxt_work_queue_name(wq, "listen");
+    /**/
+
+    ls->work_queue = wq;
+    ls->handler = nxt_stream_connection_init;
+
+    /*
+     * Connection memory pool chunk size is tunned to
+     * allocate the most data in one mem_pool chunk.
+     */
+    ls->mem_pool_size = nxt_listen_socket_pool_min_size(ls)
+                        + sizeof(nxt_event_conn_proxy_t)
+                        + sizeof(nxt_event_conn_t)
+                        + 4 * sizeof(nxt_buf_t);
+#endif
+
+    return NXT_OK;
+}
+
+
+nxt_listen_socket_t *
+nxt_cycle_listen_socket_add(nxt_cycle_t *cycle, nxt_sockaddr_t *sa)
+{
+    nxt_mem_pool_t       *mp;
+    nxt_listen_socket_t  *ls;
+
+    ls = nxt_array_zero_add(cycle->listen_sockets);
+    if (ls == NULL) {
+        return NULL;
+    }
+
+    mp = cycle->mem_pool;
+
+    ls->sockaddr = nxt_sockaddr_create(mp, &sa->u.sockaddr, nxt_socklen(sa));
+    if (ls->sockaddr == NULL) {
+        return NULL;
+    }
+
+    ls->sockaddr->type = sa->type;
+
+    if (nxt_sockaddr_text(mp, ls->sockaddr, 1) != NXT_OK) {
+        return NULL;
+    }
+
+    ls->socket = -1;
+    ls->backlog = NXT_LISTEN_BACKLOG;
+
+    return ls;
+}
+
+
+static nxt_int_t
+nxt_cycle_hostname(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    size_t  len;
+    char    hostname[NXT_MAXHOSTNAMELEN + 1];
+
+    if (gethostname(hostname, NXT_MAXHOSTNAMELEN) != 0) {
+        nxt_log_emerg(thr->log, "gethostname() failed %E", nxt_errno);
+        return NXT_ERROR;
+    }
+
+    /*
+     * Linux gethostname(2):
+     *
+     *    If the null-terminated hostname is too large to fit,
+     *    then the name is truncated, and no error is returned.
+     *
+     * For this reason an additional byte is reserved in the buffer.
+     */
+    hostname[NXT_MAXHOSTNAMELEN] = '\0';
+
+    len = nxt_strlen(hostname);
+    cycle->hostname.len = len;
+
+    cycle->hostname.data = nxt_mem_nalloc(cycle->mem_pool, len);
+
+    if (cycle->hostname.data != NULL) {
+        nxt_memcpy_lowcase(cycle->hostname.data, (u_char *) hostname, len);
+        return NXT_OK;
+    }
+
+    return NXT_ERROR;
+}
+
+
+static nxt_int_t
+nxt_cycle_log_files_init(nxt_cycle_t *cycle)
+{
+    nxt_uint_t  n;
+    nxt_file_t  *file;
+    nxt_list_t  *log_files;
+
+    n = (cycle->previous != NULL) ? nxt_list_nelts(cycle->previous->log_files):
+                                    1;
+
+    log_files = nxt_list_create(cycle->mem_pool, n, sizeof(nxt_file_t));
+
+    if (nxt_fast_path(log_files != NULL)) {
+        cycle->log_files = log_files;
+
+        /* Preallocate the main error_log.  This allocation cannot fail. */
+        file = nxt_list_zero_add(log_files);
+
+        file->fd = NXT_FILE_INVALID;
+        file->log_level = NXT_LOG_CRIT;
+
+        return NXT_OK;
+    }
+
+    return NXT_ERROR;
+}
+
+
+nxt_file_t *
+nxt_cycle_log_file_add(nxt_cycle_t *cycle, nxt_str_t *name)
+{
+    nxt_int_t            ret;
+    nxt_str_t            *prefix;
+    nxt_file_t           *file;
+    nxt_file_name_str_t  file_name;
+
+    prefix = nxt_file_name_is_absolute(name->data) ? NULL : cycle->prefix;
+
+    ret = nxt_file_name_create(cycle->mem_pool, &file_name, "%V%V%Z",
+                               prefix, name);
+
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NULL;
+    }
+
+    nxt_list_each(file, cycle->log_files) {
+
+        /* STUB: hardecoded case sensitive/insensitive. */
+
+        if (file->name != NULL
+            && nxt_file_name_eq(file->name, file_name.start))
+        {
+            return file;
+        }
+
+    } nxt_list_loop;
+
+    file = nxt_list_zero_add(cycle->log_files);
+
+    if (nxt_slow_path(file == NULL)) {
+        return NULL;
+    }
+
+    file->fd = NXT_FILE_INVALID;
+    file->log_level = NXT_LOG_CRIT;
+    file->name = file_name.start;
+
+    return file;
+}
+
+
+static nxt_int_t
+nxt_cycle_log_files_create(nxt_cycle_t *cycle)
+{
+    nxt_int_t   ret;
+    nxt_file_t  *file;
+
+    nxt_list_each(file, cycle->log_files) {
+
+        ret = nxt_file_open(file, NXT_FILE_APPEND, NXT_FILE_CREATE_OR_OPEN,
+                            NXT_FILE_OWNER_ACCESS);
+
+        if (ret != NXT_OK) {
+            return NXT_ERROR;
+        }
+
+    } nxt_list_loop;
+
+    file = nxt_list_first(cycle->log_files);
+
+    return nxt_file_stderr(file);
+}
+
+
+static nxt_int_t
+nxt_cycle_listen_sockets_create(nxt_cycle_t *cycle)
+{
+    nxt_uint_t           c, p, ncurr, nprev;
+    nxt_listen_socket_t  *curr, *prev;
+
+    curr = cycle->listen_sockets->elts;
+    ncurr = cycle->listen_sockets->nelts;
+
+    if (cycle->previous != NULL) {
+        prev = cycle->previous->listen_sockets->elts;
+        nprev = cycle->previous->listen_sockets->nelts;
+
+    } else if (cycle->inherited_sockets != NULL) {
+        prev = cycle->inherited_sockets->elts;
+        nprev = cycle->inherited_sockets->nelts;
+
+    } else {
+        prev = NULL;
+        nprev = 0;
+    }
+
+    for (c = 0; c < ncurr; c++) {
+
+        for (p = 0; p < nprev; p++) {
+
+            if (nxt_sockaddr_cmp(curr[c].sockaddr, prev[p].sockaddr)) {
+
+                if (nxt_listen_socket_update(&curr[c], &prev[p]) != NXT_OK) {
+                    return NXT_ERROR;
+                }
+
+                goto next;
+            }
+        }
+
+        if (nxt_listen_socket_create(&curr[c], cycle->test_config) != NXT_OK) {
+            return NXT_ERROR;
+        }
+
+    next:
+
+        continue;
+    }
+
+    return NXT_OK;
+}
+
+
+static void
+nxt_cycle_listen_sockets_close(nxt_cycle_t *cycle)
+{
+    nxt_uint_t           p, c, nprev, ncurr;
+    nxt_listen_socket_t  *curr, *prev;
+
+    if (cycle->previous == NULL) {
+        return;
+    }
+
+    prev = cycle->previous->listen_sockets->elts;
+    nprev = cycle->previous->listen_sockets->nelts;
+
+    curr = cycle->listen_sockets->elts;
+    ncurr = cycle->listen_sockets->nelts;
+
+    for (p = 0; p < nprev; p++) {
+
+        for (c = 0; c < ncurr; c++) {
+            if (nxt_sockaddr_cmp(prev[p].sockaddr, curr[c].sockaddr)) {
+                goto next;
+            }
+        }
+
+        nxt_socket_close(prev[p].socket);
+
+    next:
+
+        continue;
+    }
+
+    return;
+}
+
+
+nxt_int_t
+nxt_cycle_listen_sockets_enable(nxt_thread_t *thr, nxt_cycle_t *cycle)
+{
+    nxt_uint_t           i, n;
+    nxt_listen_socket_t  *ls;
+
+    ls = cycle->listen_sockets->elts;
+    n = cycle->listen_sockets->nelts;
+
+    for (i = 0; i < n; i++) {
+        if (nxt_event_conn_listen(thr, &ls[i]) != NXT_OK) {
+            return NXT_ERROR;
+        }
+    }
+
+    return NXT_OK;
+}
+
+
+nxt_str_t *
+nxt_current_directory(nxt_mem_pool_t *mp)
+{
+    size_t     len;
+    u_char     *p;
+    nxt_str_t  *name;
+    char       buf[NXT_MAX_PATH_LEN];
+
+    len = nxt_dir_current(buf, NXT_MAX_PATH_LEN);
+
+    if (nxt_fast_path(len != 0)) {
+        name = nxt_str_alloc(mp, len + 1);
+
+        if (nxt_fast_path(name != NULL)) {
+            p = nxt_cpymem(name->data, buf, len);
+            *p = '/';
+
+            return name;
+        }
+    }
+
+    return NULL;
+}
+
+
+nxt_int_t
+nxt_cycle_pid_file_create(nxt_file_name_t *pid_file, nxt_bool_t test)
+{
+    ssize_t     len;
+    nxt_int_t   n;
+    nxt_uint_t  create;
+    nxt_file_t  file;
+    u_char      pid[NXT_INT64_T_LEN + NXT_LINEFEED_SIZE];
+
+    nxt_memzero(&file, sizeof(nxt_file_t));
+
+    file.name = pid_file;
+
+    create = test ? NXT_FILE_CREATE_OR_OPEN : NXT_FILE_TRUNCATE;
+
+    n = nxt_file_open(&file, NXT_FILE_WRONLY, create, NXT_FILE_DEFAULT_ACCESS);
+
+    if (n != NXT_OK) {
+        return NXT_ERROR;
+    }
+
+    if (!test) {
+        len = nxt_sprintf(pid, pid + sizeof(pid), "%PI%n", nxt_pid) - pid;
+
+        if (nxt_file_write(&file, pid, len, 0) != len) {
+            return NXT_ERROR;
+        }
+    }
+
+    nxt_file_close(&file);
+
+    return NXT_OK;
+}
+
+
+static void
+nxt_cycle_pid_file_delete(nxt_cycle_t *cycle)
+{
+    nxt_file_name_t  *pid_file;
+
+    if (!cycle->test_config) {
+        pid_file = (cycle->new_binary != 0) ? cycle->oldbin_file:
+                                              cycle->pid_file;
+        if (pid_file != NULL) {
+            nxt_file_delete(pid_file);
+        }
+    }
+}
+
+
+nxt_int_t
+nxt_cycle_shm_zone_add(nxt_cycle_t *cycle, nxt_str_t *name, size_t size,
+    nxt_uint_t page_size)
+{
+    nxt_cycle_shm_zone_t  *shm_zone;
+
+    if (cycle->shm_zones == NULL) {
+        cycle->shm_zones = nxt_array_create(cycle->mem_pool, 1,
+                                            sizeof(nxt_cycle_shm_zone_t));
+        if (cycle->shm_zones == NULL) {
+            return NXT_ERROR;
+        }
+    }
+
+    shm_zone = nxt_array_add(cycle->shm_zones);
+
+    if (shm_zone != NULL) {
+        shm_zone->size = size;
+        shm_zone->page_size = page_size;
+        shm_zone->name = *name;
+
+        return NXT_OK;
+    }
+
+    return NXT_ERROR;
+}
+
+
+static nxt_int_t
+nxt_cycle_shm_zones_enable(nxt_cycle_t *cycle)
+{
+    nxt_uint_t            i, n;
+    nxt_cycle_shm_zone_t  *shm_zone;
+
+    if (cycle->shm_zones != NULL) {
+        shm_zone = cycle->shm_zones->elts;
+        n = cycle->shm_zones->nelts;
+
+        for (i = 0; i < n; i++) {
+            if (nxt_cycle_shm_zone_create(&shm_zone[i]) != NXT_OK) {
+                return NXT_ERROR;
+            }
+        }
+    }
+
+    return NXT_OK;
+}
+
+
+static nxt_int_t
+nxt_cycle_shm_zone_create(nxt_cycle_shm_zone_t *shm_zone)
+{
+    nxt_mem_zone_t  *zone;
+
+    /*
+     * Unix-only code because Windows ASLR maps shared memory segments at
+     * different addresses in different processes.  Unix ASLR does not affect
+     * this because all shared memory segments are inherited during fork().
+     */
+
+    shm_zone->addr = nxt_mem_mmap(NULL, shm_zone->size,
+                                  NXT_MEM_MAP_READ | NXT_MEM_MAP_WRITE,
+                                  NXT_MEM_MAP_SHARED, NXT_FILE_INVALID, 0);
+
+    if (shm_zone->addr != NXT_MEM_MAP_FAILED) {
+
+        zone = nxt_mem_zone_init(shm_zone->addr, shm_zone->size,
+                                 shm_zone->page_size);
+        if (zone != NULL) {
+            return NXT_OK;
+        }
+
+        nxt_mem_munmap(shm_zone->addr, shm_zone->size);
+    }
+
+    return NXT_ERROR;
+}