view src/core/nginx.c @ 6153:4f6efabcb09b

The "reuseport" option of the "listen" directive. When configured, an individual listen socket on a given address is created for each worker process. This allows to reduce in-kernel lock contention on configurations with high accept rates, resulting in better performance. As of now it works on Linux and DragonFly BSD. Note that on Linux incoming connection requests are currently tied up to a specific listen socket, and if some sockets are closed, connection requests will be reset, see https://lwn.net/Articles/542629/. With nginx, this may happen if the number of worker processes is reduced. There is no such problem on DragonFly BSD. Based on previous work by Sepherosa Ziehau and Yingqi Lu.
author Maxim Dounin <mdounin@mdounin.ru>
date Wed, 20 May 2015 15:51:56 +0300
parents 967594ba7571
children 1b7e246e6b38
line wrap: on
line source


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


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


static ngx_int_t ngx_add_inherited_sockets(ngx_cycle_t *cycle);
static ngx_int_t ngx_get_options(int argc, char *const *argv);
static ngx_int_t ngx_process_options(ngx_cycle_t *cycle);
static ngx_int_t ngx_save_argv(ngx_cycle_t *cycle, int argc, char *const *argv);
static void *ngx_core_module_create_conf(ngx_cycle_t *cycle);
static char *ngx_core_module_init_conf(ngx_cycle_t *cycle, void *conf);
static char *ngx_set_user(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
static char *ngx_set_env(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
static char *ngx_set_priority(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
static char *ngx_set_cpu_affinity(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_set_worker_processes(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);


static ngx_conf_enum_t  ngx_debug_points[] = {
    { ngx_string("stop"), NGX_DEBUG_POINTS_STOP },
    { ngx_string("abort"), NGX_DEBUG_POINTS_ABORT },
    { ngx_null_string, 0 }
};


static ngx_command_t  ngx_core_commands[] = {

    { ngx_string("daemon"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      0,
      offsetof(ngx_core_conf_t, daemon),
      NULL },

    { ngx_string("master_process"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      0,
      offsetof(ngx_core_conf_t, master),
      NULL },

    { ngx_string("timer_resolution"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_msec_slot,
      0,
      offsetof(ngx_core_conf_t, timer_resolution),
      NULL },

    { ngx_string("pid"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      0,
      offsetof(ngx_core_conf_t, pid),
      NULL },

    { ngx_string("lock_file"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      0,
      offsetof(ngx_core_conf_t, lock_file),
      NULL },

    { ngx_string("worker_processes"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_set_worker_processes,
      0,
      0,
      NULL },

    { ngx_string("debug_points"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_enum_slot,
      0,
      offsetof(ngx_core_conf_t, debug_points),
      &ngx_debug_points },

    { ngx_string("user"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE12,
      ngx_set_user,
      0,
      0,
      NULL },

    { ngx_string("worker_priority"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_set_priority,
      0,
      0,
      NULL },

    { ngx_string("worker_cpu_affinity"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_1MORE,
      ngx_set_cpu_affinity,
      0,
      0,
      NULL },

    { ngx_string("worker_rlimit_nofile"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      0,
      offsetof(ngx_core_conf_t, rlimit_nofile),
      NULL },

    { ngx_string("worker_rlimit_core"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_off_slot,
      0,
      offsetof(ngx_core_conf_t, rlimit_core),
      NULL },

    { ngx_string("working_directory"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      0,
      offsetof(ngx_core_conf_t, working_directory),
      NULL },

    { ngx_string("env"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_set_env,
      0,
      0,
      NULL },

      ngx_null_command
};


static ngx_core_module_t  ngx_core_module_ctx = {
    ngx_string("core"),
    ngx_core_module_create_conf,
    ngx_core_module_init_conf
};


ngx_module_t  ngx_core_module = {
    NGX_MODULE_V1,
    &ngx_core_module_ctx,                  /* module context */
    ngx_core_commands,                     /* module directives */
    NGX_CORE_MODULE,                       /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


ngx_uint_t          ngx_max_module;

static ngx_uint_t   ngx_show_help;
static ngx_uint_t   ngx_show_version;
static ngx_uint_t   ngx_show_configure;
static u_char      *ngx_prefix;
static u_char      *ngx_conf_file;
static u_char      *ngx_conf_params;
static char        *ngx_signal;


static char **ngx_os_environ;


int ngx_cdecl
main(int argc, char *const *argv)
{
    ngx_int_t         i;
    ngx_log_t        *log;
    ngx_cycle_t      *cycle, init_cycle;
    ngx_core_conf_t  *ccf;

    ngx_debug_init();

    if (ngx_strerror_init() != NGX_OK) {
        return 1;
    }

    if (ngx_get_options(argc, argv) != NGX_OK) {
        return 1;
    }

    if (ngx_show_version) {
        ngx_write_stderr("nginx version: " NGINX_VER_BUILD NGX_LINEFEED);

        if (ngx_show_help) {
            ngx_write_stderr(
                "Usage: nginx [-?hvVtq] [-s signal] [-c filename] "
                             "[-p prefix] [-g directives]" NGX_LINEFEED
                             NGX_LINEFEED
                "Options:" NGX_LINEFEED
                "  -?,-h         : this help" NGX_LINEFEED
                "  -v            : show version and exit" NGX_LINEFEED
                "  -V            : show version and configure options then exit"
                                   NGX_LINEFEED
                "  -t            : test configuration and exit" NGX_LINEFEED
                "  -q            : suppress non-error messages "
                                   "during configuration testing" NGX_LINEFEED
                "  -s signal     : send signal to a master process: "
                                   "stop, quit, reopen, reload" NGX_LINEFEED
#ifdef NGX_PREFIX
                "  -p prefix     : set prefix path (default: "
                                   NGX_PREFIX ")" NGX_LINEFEED
#else
                "  -p prefix     : set prefix path (default: NONE)" NGX_LINEFEED
#endif
                "  -c filename   : set configuration file (default: "
                                   NGX_CONF_PATH ")" NGX_LINEFEED
                "  -g directives : set global directives out of configuration "
                                   "file" NGX_LINEFEED NGX_LINEFEED
                );
        }

        if (ngx_show_configure) {

#ifdef NGX_COMPILER
            ngx_write_stderr("built by " NGX_COMPILER NGX_LINEFEED);
#endif

#if (NGX_SSL)
            if (SSLeay() == SSLEAY_VERSION_NUMBER) {
                ngx_write_stderr("built with " OPENSSL_VERSION_TEXT
                                 NGX_LINEFEED);
            } else {
                ngx_write_stderr("built with " OPENSSL_VERSION_TEXT
                                 " (running with ");
                ngx_write_stderr((char *) (uintptr_t)
                                 SSLeay_version(SSLEAY_VERSION));
                ngx_write_stderr(")" NGX_LINEFEED);
            }
#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
            ngx_write_stderr("TLS SNI support enabled" NGX_LINEFEED);
#else
            ngx_write_stderr("TLS SNI support disabled" NGX_LINEFEED);
#endif
#endif

            ngx_write_stderr("configure arguments:" NGX_CONFIGURE NGX_LINEFEED);
        }

        if (!ngx_test_config) {
            return 0;
        }
    }

    /* TODO */ ngx_max_sockets = -1;

    ngx_time_init();

#if (NGX_PCRE)
    ngx_regex_init();
#endif

    ngx_pid = ngx_getpid();

    log = ngx_log_init(ngx_prefix);
    if (log == NULL) {
        return 1;
    }

    /* STUB */
#if (NGX_OPENSSL)
    ngx_ssl_init(log);
#endif

    /*
     * init_cycle->log is required for signal handlers and
     * ngx_process_options()
     */

    ngx_memzero(&init_cycle, sizeof(ngx_cycle_t));
    init_cycle.log = log;
    ngx_cycle = &init_cycle;

    init_cycle.pool = ngx_create_pool(1024, log);
    if (init_cycle.pool == NULL) {
        return 1;
    }

    if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) {
        return 1;
    }

    if (ngx_process_options(&init_cycle) != NGX_OK) {
        return 1;
    }

    if (ngx_os_init(log) != NGX_OK) {
        return 1;
    }

    /*
     * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init()
     */

    if (ngx_crc32_table_init() != NGX_OK) {
        return 1;
    }

    if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) {
        return 1;
    }

    ngx_max_module = 0;
    for (i = 0; ngx_modules[i]; i++) {
        ngx_modules[i]->index = ngx_max_module++;
    }

    cycle = ngx_init_cycle(&init_cycle);
    if (cycle == NULL) {
        if (ngx_test_config) {
            ngx_log_stderr(0, "configuration file %s test failed",
                           init_cycle.conf_file.data);
        }

        return 1;
    }

    if (ngx_test_config) {
        if (!ngx_quiet_mode) {
            ngx_log_stderr(0, "configuration file %s test is successful",
                           cycle->conf_file.data);
        }

        return 0;
    }

    if (ngx_signal) {
        return ngx_signal_process(cycle, ngx_signal);
    }

    ngx_os_status(cycle->log);

    ngx_cycle = cycle;

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

    if (ccf->master && ngx_process == NGX_PROCESS_SINGLE) {
        ngx_process = NGX_PROCESS_MASTER;
    }

#if !(NGX_WIN32)

    if (ngx_init_signals(cycle->log) != NGX_OK) {
        return 1;
    }

    if (!ngx_inherited && ccf->daemon) {
        if (ngx_daemon(cycle->log) != NGX_OK) {
            return 1;
        }

        ngx_daemonized = 1;
    }

    if (ngx_inherited) {
        ngx_daemonized = 1;
    }

#endif

    if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) {
        return 1;
    }

    if (ngx_log_redirect_stderr(cycle) != NGX_OK) {
        return 1;
    }

    if (log->file->fd != ngx_stderr) {
        if (ngx_close_file(log->file->fd) == NGX_FILE_ERROR) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          ngx_close_file_n " built-in log failed");
        }
    }

    ngx_use_stderr = 0;

    if (ngx_process == NGX_PROCESS_SINGLE) {
        ngx_single_process_cycle(cycle);

    } else {
        ngx_master_process_cycle(cycle);
    }

    return 0;
}


static ngx_int_t
ngx_add_inherited_sockets(ngx_cycle_t *cycle)
{
    u_char           *p, *v, *inherited;
    ngx_int_t         s;
    ngx_listening_t  *ls;

    inherited = (u_char *) getenv(NGINX_VAR);

    if (inherited == NULL) {
        return NGX_OK;
    }

    ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0,
                  "using inherited sockets from \"%s\"", inherited);

    if (ngx_array_init(&cycle->listening, cycle->pool, 10,
                       sizeof(ngx_listening_t))
        != NGX_OK)
    {
        return NGX_ERROR;
    }

    for (p = inherited, v = p; *p; p++) {
        if (*p == ':' || *p == ';') {
            s = ngx_atoi(v, p - v);
            if (s == NGX_ERROR) {
                ngx_log_error(NGX_LOG_EMERG, cycle->log, 0,
                              "invalid socket number \"%s\" in " NGINX_VAR
                              " environment variable, ignoring the rest"
                              " of the variable", v);
                break;
            }

            v = p + 1;

            ls = ngx_array_push(&cycle->listening);
            if (ls == NULL) {
                return NGX_ERROR;
            }

            ngx_memzero(ls, sizeof(ngx_listening_t));

            ls->fd = (ngx_socket_t) s;
        }
    }

    ngx_inherited = 1;

    return ngx_set_inherited_sockets(cycle);
}


char **
ngx_set_environment(ngx_cycle_t *cycle, ngx_uint_t *last)
{
    char             **p, **env;
    ngx_str_t         *var;
    ngx_uint_t         i, n;
    ngx_core_conf_t   *ccf;

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

    if (last == NULL && ccf->environment) {
        return ccf->environment;
    }

    var = ccf->env.elts;

    for (i = 0; i < ccf->env.nelts; i++) {
        if (ngx_strcmp(var[i].data, "TZ") == 0
            || ngx_strncmp(var[i].data, "TZ=", 3) == 0)
        {
            goto tz_found;
        }
    }

    var = ngx_array_push(&ccf->env);
    if (var == NULL) {
        return NULL;
    }

    var->len = 2;
    var->data = (u_char *) "TZ";

    var = ccf->env.elts;

tz_found:

    n = 0;

    for (i = 0; i < ccf->env.nelts; i++) {

        if (var[i].data[var[i].len] == '=') {
            n++;
            continue;
        }

        for (p = ngx_os_environ; *p; p++) {

            if (ngx_strncmp(*p, var[i].data, var[i].len) == 0
                && (*p)[var[i].len] == '=')
            {
                n++;
                break;
            }
        }
    }

    if (last) {
        env = ngx_alloc((*last + n + 1) * sizeof(char *), cycle->log);
        *last = n;

    } else {
        env = ngx_palloc(cycle->pool, (n + 1) * sizeof(char *));
    }

    if (env == NULL) {
        return NULL;
    }

    n = 0;

    for (i = 0; i < ccf->env.nelts; i++) {

        if (var[i].data[var[i].len] == '=') {
            env[n++] = (char *) var[i].data;
            continue;
        }

        for (p = ngx_os_environ; *p; p++) {

            if (ngx_strncmp(*p, var[i].data, var[i].len) == 0
                && (*p)[var[i].len] == '=')
            {
                env[n++] = *p;
                break;
            }
        }
    }

    env[n] = NULL;

    if (last == NULL) {
        ccf->environment = env;
        environ = env;
    }

    return env;
}


ngx_pid_t
ngx_exec_new_binary(ngx_cycle_t *cycle, char *const *argv)
{
    char             **env, *var;
    u_char            *p;
    ngx_uint_t         i, n;
    ngx_pid_t          pid;
    ngx_exec_ctx_t     ctx;
    ngx_core_conf_t   *ccf;
    ngx_listening_t   *ls;

    ngx_memzero(&ctx, sizeof(ngx_exec_ctx_t));

    ctx.path = argv[0];
    ctx.name = "new binary process";
    ctx.argv = argv;

    n = 2;
    env = ngx_set_environment(cycle, &n);
    if (env == NULL) {
        return NGX_INVALID_PID;
    }

    var = ngx_alloc(sizeof(NGINX_VAR)
                    + cycle->listening.nelts * (NGX_INT32_LEN + 1) + 2,
                    cycle->log);
    if (var == NULL) {
        ngx_free(env);
        return NGX_INVALID_PID;
    }

    p = ngx_cpymem(var, NGINX_VAR "=", sizeof(NGINX_VAR));

    ls = cycle->listening.elts;
    for (i = 0; i < cycle->listening.nelts; i++) {
        p = ngx_sprintf(p, "%ud;", ls[i].fd);
    }

    *p = '\0';

    env[n++] = var;

#if (NGX_SETPROCTITLE_USES_ENV)

    /* allocate the spare 300 bytes for the new binary process title */

    env[n++] = "SPARE=XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX";

#endif

    env[n] = NULL;

#if (NGX_DEBUG)
    {
    char  **e;
    for (e = env; *e; e++) {
        ngx_log_debug1(NGX_LOG_DEBUG_CORE, cycle->log, 0, "env: %s", *e);
    }
    }
#endif

    ctx.envp = (char *const *) env;

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

    if (ngx_rename_file(ccf->pid.data, ccf->oldpid.data) == NGX_FILE_ERROR) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      ngx_rename_file_n " %s to %s failed "
                      "before executing new binary process \"%s\"",
                      ccf->pid.data, ccf->oldpid.data, argv[0]);

        ngx_free(env);
        ngx_free(var);

        return NGX_INVALID_PID;
    }

    pid = ngx_execute(cycle, &ctx);

    if (pid == NGX_INVALID_PID) {
        if (ngx_rename_file(ccf->oldpid.data, ccf->pid.data)
            == NGX_FILE_ERROR)
        {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          ngx_rename_file_n " %s back to %s failed after "
                          "an attempt to execute new binary process \"%s\"",
                          ccf->oldpid.data, ccf->pid.data, argv[0]);
        }
    }

    ngx_free(env);
    ngx_free(var);

    return pid;
}


static ngx_int_t
ngx_get_options(int argc, char *const *argv)
{
    u_char     *p;
    ngx_int_t   i;

    for (i = 1; i < argc; i++) {

        p = (u_char *) argv[i];

        if (*p++ != '-') {
            ngx_log_stderr(0, "invalid option: \"%s\"", argv[i]);
            return NGX_ERROR;
        }

        while (*p) {

            switch (*p++) {

            case '?':
            case 'h':
                ngx_show_version = 1;
                ngx_show_help = 1;
                break;

            case 'v':
                ngx_show_version = 1;
                break;

            case 'V':
                ngx_show_version = 1;
                ngx_show_configure = 1;
                break;

            case 't':
                ngx_test_config = 1;
                break;

            case 'q':
                ngx_quiet_mode = 1;
                break;

            case 'p':
                if (*p) {
                    ngx_prefix = p;
                    goto next;
                }

                if (argv[++i]) {
                    ngx_prefix = (u_char *) argv[i];
                    goto next;
                }

                ngx_log_stderr(0, "option \"-p\" requires directory name");
                return NGX_ERROR;

            case 'c':
                if (*p) {
                    ngx_conf_file = p;
                    goto next;
                }

                if (argv[++i]) {
                    ngx_conf_file = (u_char *) argv[i];
                    goto next;
                }

                ngx_log_stderr(0, "option \"-c\" requires file name");
                return NGX_ERROR;

            case 'g':
                if (*p) {
                    ngx_conf_params = p;
                    goto next;
                }

                if (argv[++i]) {
                    ngx_conf_params = (u_char *) argv[i];
                    goto next;
                }

                ngx_log_stderr(0, "option \"-g\" requires parameter");
                return NGX_ERROR;

            case 's':
                if (*p) {
                    ngx_signal = (char *) p;

                } else if (argv[++i]) {
                    ngx_signal = argv[i];

                } else {
                    ngx_log_stderr(0, "option \"-s\" requires parameter");
                    return NGX_ERROR;
                }

                if (ngx_strcmp(ngx_signal, "stop") == 0
                    || ngx_strcmp(ngx_signal, "quit") == 0
                    || ngx_strcmp(ngx_signal, "reopen") == 0
                    || ngx_strcmp(ngx_signal, "reload") == 0)
                {
                    ngx_process = NGX_PROCESS_SIGNALLER;
                    goto next;
                }

                ngx_log_stderr(0, "invalid option: \"-s %s\"", ngx_signal);
                return NGX_ERROR;

            default:
                ngx_log_stderr(0, "invalid option: \"%c\"", *(p - 1));
                return NGX_ERROR;
            }
        }

    next:

        continue;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_save_argv(ngx_cycle_t *cycle, int argc, char *const *argv)
{
#if (NGX_FREEBSD)

    ngx_os_argv = (char **) argv;
    ngx_argc = argc;
    ngx_argv = (char **) argv;

#else
    size_t     len;
    ngx_int_t  i;

    ngx_os_argv = (char **) argv;
    ngx_argc = argc;

    ngx_argv = ngx_alloc((argc + 1) * sizeof(char *), cycle->log);
    if (ngx_argv == NULL) {
        return NGX_ERROR;
    }

    for (i = 0; i < argc; i++) {
        len = ngx_strlen(argv[i]) + 1;

        ngx_argv[i] = ngx_alloc(len, cycle->log);
        if (ngx_argv[i] == NULL) {
            return NGX_ERROR;
        }

        (void) ngx_cpystrn((u_char *) ngx_argv[i], (u_char *) argv[i], len);
    }

    ngx_argv[i] = NULL;

#endif

    ngx_os_environ = environ;

    return NGX_OK;
}


static ngx_int_t
ngx_process_options(ngx_cycle_t *cycle)
{
    u_char  *p;
    size_t   len;

    if (ngx_prefix) {
        len = ngx_strlen(ngx_prefix);
        p = ngx_prefix;

        if (len && !ngx_path_separator(p[len - 1])) {
            p = ngx_pnalloc(cycle->pool, len + 1);
            if (p == NULL) {
                return NGX_ERROR;
            }

            ngx_memcpy(p, ngx_prefix, len);
            p[len++] = '/';
        }

        cycle->conf_prefix.len = len;
        cycle->conf_prefix.data = p;
        cycle->prefix.len = len;
        cycle->prefix.data = p;

    } else {

#ifndef NGX_PREFIX

        p = ngx_pnalloc(cycle->pool, NGX_MAX_PATH);
        if (p == NULL) {
            return NGX_ERROR;
        }

        if (ngx_getcwd(p, NGX_MAX_PATH) == 0) {
            ngx_log_stderr(ngx_errno, "[emerg]: " ngx_getcwd_n " failed");
            return NGX_ERROR;
        }

        len = ngx_strlen(p);

        p[len++] = '/';

        cycle->conf_prefix.len = len;
        cycle->conf_prefix.data = p;
        cycle->prefix.len = len;
        cycle->prefix.data = p;

#else

#ifdef NGX_CONF_PREFIX
        ngx_str_set(&cycle->conf_prefix, NGX_CONF_PREFIX);
#else
        ngx_str_set(&cycle->conf_prefix, NGX_PREFIX);
#endif
        ngx_str_set(&cycle->prefix, NGX_PREFIX);

#endif
    }

    if (ngx_conf_file) {
        cycle->conf_file.len = ngx_strlen(ngx_conf_file);
        cycle->conf_file.data = ngx_conf_file;

    } else {
        ngx_str_set(&cycle->conf_file, NGX_CONF_PATH);
    }

    if (ngx_conf_full_name(cycle, &cycle->conf_file, 0) != NGX_OK) {
        return NGX_ERROR;
    }

    for (p = cycle->conf_file.data + cycle->conf_file.len - 1;
         p > cycle->conf_file.data;
         p--)
    {
        if (ngx_path_separator(*p)) {
            cycle->conf_prefix.len = p - ngx_cycle->conf_file.data + 1;
            cycle->conf_prefix.data = ngx_cycle->conf_file.data;
            break;
        }
    }

    if (ngx_conf_params) {
        cycle->conf_param.len = ngx_strlen(ngx_conf_params);
        cycle->conf_param.data = ngx_conf_params;
    }

    if (ngx_test_config) {
        cycle->log->log_level = NGX_LOG_INFO;
    }

    return NGX_OK;
}


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

    ccf = ngx_pcalloc(cycle->pool, sizeof(ngx_core_conf_t));
    if (ccf == NULL) {
        return NULL;
    }

    /*
     * set by ngx_pcalloc()
     *
     *     ccf->pid = NULL;
     *     ccf->oldpid = NULL;
     *     ccf->priority = 0;
     *     ccf->cpu_affinity_n = 0;
     *     ccf->cpu_affinity = NULL;
     */

    ccf->daemon = NGX_CONF_UNSET;
    ccf->master = NGX_CONF_UNSET;
    ccf->timer_resolution = NGX_CONF_UNSET_MSEC;

    ccf->worker_processes = NGX_CONF_UNSET;
    ccf->debug_points = NGX_CONF_UNSET;

    ccf->rlimit_nofile = NGX_CONF_UNSET;
    ccf->rlimit_core = NGX_CONF_UNSET;

    ccf->user = (ngx_uid_t) NGX_CONF_UNSET_UINT;
    ccf->group = (ngx_gid_t) NGX_CONF_UNSET_UINT;

    if (ngx_array_init(&ccf->env, cycle->pool, 1, sizeof(ngx_str_t))
        != NGX_OK)
    {
        return NULL;
    }

    return ccf;
}


static char *
ngx_core_module_init_conf(ngx_cycle_t *cycle, void *conf)
{
    ngx_core_conf_t  *ccf = conf;

    ngx_conf_init_value(ccf->daemon, 1);
    ngx_conf_init_value(ccf->master, 1);
    ngx_conf_init_msec_value(ccf->timer_resolution, 0);

    ngx_conf_init_value(ccf->worker_processes, 1);
    ngx_conf_init_value(ccf->debug_points, 0);

#if (NGX_HAVE_CPU_AFFINITY)

    if (ccf->cpu_affinity_n
        && ccf->cpu_affinity_n != 1
        && ccf->cpu_affinity_n != (ngx_uint_t) ccf->worker_processes)
    {
        ngx_log_error(NGX_LOG_WARN, cycle->log, 0,
                      "the number of \"worker_processes\" is not equal to "
                      "the number of \"worker_cpu_affinity\" masks, "
                      "using last mask for remaining worker processes");
    }

#endif


    if (ccf->pid.len == 0) {
        ngx_str_set(&ccf->pid, NGX_PID_PATH);
    }

    if (ngx_conf_full_name(cycle, &ccf->pid, 0) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    ccf->oldpid.len = ccf->pid.len + sizeof(NGX_OLDPID_EXT);

    ccf->oldpid.data = ngx_pnalloc(cycle->pool, ccf->oldpid.len);
    if (ccf->oldpid.data == NULL) {
        return NGX_CONF_ERROR;
    }

    ngx_memcpy(ngx_cpymem(ccf->oldpid.data, ccf->pid.data, ccf->pid.len),
               NGX_OLDPID_EXT, sizeof(NGX_OLDPID_EXT));


#if !(NGX_WIN32)

    if (ccf->user == (uid_t) NGX_CONF_UNSET_UINT && geteuid() == 0) {
        struct group   *grp;
        struct passwd  *pwd;

        ngx_set_errno(0);
        pwd = getpwnam(NGX_USER);
        if (pwd == NULL) {
            ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
                          "getpwnam(\"" NGX_USER "\") failed");
            return NGX_CONF_ERROR;
        }

        ccf->username = NGX_USER;
        ccf->user = pwd->pw_uid;

        ngx_set_errno(0);
        grp = getgrnam(NGX_GROUP);
        if (grp == NULL) {
            ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
                          "getgrnam(\"" NGX_GROUP "\") failed");
            return NGX_CONF_ERROR;
        }

        ccf->group = grp->gr_gid;
    }


    if (ccf->lock_file.len == 0) {
        ngx_str_set(&ccf->lock_file, NGX_LOCK_PATH);
    }

    if (ngx_conf_full_name(cycle, &ccf->lock_file, 0) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    {
    ngx_str_t  lock_file;

    lock_file = cycle->old_cycle->lock_file;

    if (lock_file.len) {
        lock_file.len--;

        if (ccf->lock_file.len != lock_file.len
            || ngx_strncmp(ccf->lock_file.data, lock_file.data, lock_file.len)
               != 0)
        {
            ngx_log_error(NGX_LOG_EMERG, cycle->log, 0,
                          "\"lock_file\" could not be changed, ignored");
        }

        cycle->lock_file.len = lock_file.len + 1;
        lock_file.len += sizeof(".accept");

        cycle->lock_file.data = ngx_pstrdup(cycle->pool, &lock_file);
        if (cycle->lock_file.data == NULL) {
            return NGX_CONF_ERROR;
        }

    } else {
        cycle->lock_file.len = ccf->lock_file.len + 1;
        cycle->lock_file.data = ngx_pnalloc(cycle->pool,
                                      ccf->lock_file.len + sizeof(".accept"));
        if (cycle->lock_file.data == NULL) {
            return NGX_CONF_ERROR;
        }

        ngx_memcpy(ngx_cpymem(cycle->lock_file.data, ccf->lock_file.data,
                              ccf->lock_file.len),
                   ".accept", sizeof(".accept"));
    }
    }

#endif

    return NGX_CONF_OK;
}


static char *
ngx_set_user(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
#if (NGX_WIN32)

    ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                       "\"user\" is not supported, ignored");

    return NGX_CONF_OK;

#else

    ngx_core_conf_t  *ccf = conf;

    char             *group;
    struct passwd    *pwd;
    struct group     *grp;
    ngx_str_t        *value;

    if (ccf->user != (uid_t) NGX_CONF_UNSET_UINT) {
        return "is duplicate";
    }

    if (geteuid() != 0) {
        ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                           "the \"user\" directive makes sense only "
                           "if the master process runs "
                           "with super-user privileges, ignored");
        return NGX_CONF_OK;
    }

    value = (ngx_str_t *) cf->args->elts;

    ccf->username = (char *) value[1].data;

    ngx_set_errno(0);
    pwd = getpwnam((const char *) value[1].data);
    if (pwd == NULL) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
                           "getpwnam(\"%s\") failed", value[1].data);
        return NGX_CONF_ERROR;
    }

    ccf->user = pwd->pw_uid;

    group = (char *) ((cf->args->nelts == 2) ? value[1].data : value[2].data);

    ngx_set_errno(0);
    grp = getgrnam(group);
    if (grp == NULL) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
                           "getgrnam(\"%s\") failed", group);
        return NGX_CONF_ERROR;
    }

    ccf->group = grp->gr_gid;

    return NGX_CONF_OK;

#endif
}


static char *
ngx_set_env(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_core_conf_t  *ccf = conf;

    ngx_str_t   *value, *var;
    ngx_uint_t   i;

    var = ngx_array_push(&ccf->env);
    if (var == NULL) {
        return NGX_CONF_ERROR;
    }

    value = cf->args->elts;
    *var = value[1];

    for (i = 0; i < value[1].len; i++) {

        if (value[1].data[i] == '=') {

            var->len = i;

            return NGX_CONF_OK;
        }
    }

    return NGX_CONF_OK;
}


static char *
ngx_set_priority(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_core_conf_t  *ccf = conf;

    ngx_str_t        *value;
    ngx_uint_t        n, minus;

    if (ccf->priority != 0) {
        return "is duplicate";
    }

    value = cf->args->elts;

    if (value[1].data[0] == '-') {
        n = 1;
        minus = 1;

    } else if (value[1].data[0] == '+') {
        n = 1;
        minus = 0;

    } else {
        n = 0;
        minus = 0;
    }

    ccf->priority = ngx_atoi(&value[1].data[n], value[1].len - n);
    if (ccf->priority == NGX_ERROR) {
        return "invalid number";
    }

    if (minus) {
        ccf->priority = -ccf->priority;
    }

    return NGX_CONF_OK;
}


static char *
ngx_set_cpu_affinity(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
#if (NGX_HAVE_CPU_AFFINITY)
    ngx_core_conf_t  *ccf = conf;

    u_char            ch;
    uint64_t         *mask;
    ngx_str_t        *value;
    ngx_uint_t        i, n;

    if (ccf->cpu_affinity) {
        return "is duplicate";
    }

    mask = ngx_palloc(cf->pool, (cf->args->nelts - 1) * sizeof(uint64_t));
    if (mask == NULL) {
        return NGX_CONF_ERROR;
    }

    ccf->cpu_affinity_n = cf->args->nelts - 1;
    ccf->cpu_affinity = mask;

    value = cf->args->elts;

    for (n = 1; n < cf->args->nelts; n++) {

        if (value[n].len > 64) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                         "\"worker_cpu_affinity\" supports up to 64 CPUs only");
            return NGX_CONF_ERROR;
        }

        mask[n - 1] = 0;

        for (i = 0; i < value[n].len; i++) {

            ch = value[n].data[i];

            if (ch == ' ') {
                continue;
            }

            mask[n - 1] <<= 1;

            if (ch == '0') {
                continue;
            }

            if (ch == '1') {
                mask[n - 1] |= 1;
                continue;
            }

            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                          "invalid character \"%c\" in \"worker_cpu_affinity\"",
                          ch);
            return NGX_CONF_ERROR;
        }
    }

#else

    ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                       "\"worker_cpu_affinity\" is not supported "
                       "on this platform, ignored");
#endif

    return NGX_CONF_OK;
}


uint64_t
ngx_get_cpu_affinity(ngx_uint_t n)
{
    ngx_core_conf_t  *ccf;

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

    if (ccf->cpu_affinity == NULL) {
        return 0;
    }

    if (ccf->cpu_affinity_n > n) {
        return ccf->cpu_affinity[n];
    }

    return ccf->cpu_affinity[ccf->cpu_affinity_n - 1];
}


static char *
ngx_set_worker_processes(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_str_t        *value;
    ngx_core_conf_t  *ccf;

    ccf = (ngx_core_conf_t *) conf;

    if (ccf->worker_processes != NGX_CONF_UNSET) {
        return "is duplicate";
    }

    value = (ngx_str_t *) cf->args->elts;

    if (ngx_strcmp(value[1].data, "auto") == 0) {
        ccf->worker_processes = ngx_ncpu;
        return NGX_CONF_OK;
    }

    ccf->worker_processes = ngx_atoi(value[1].data, value[1].len);

    if (ccf->worker_processes == NGX_ERROR) {
        return "invalid value";
    }

    return NGX_CONF_OK;
}