
/*
 * Copyright (C) Igor Sysoev
 */


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


static ngx_int_t ngx_add_inherited_sockets(ngx_cycle_t *cycle);
static ngx_int_t ngx_getopt(ngx_cycle_t *cycle, int argc, char *const *argv);
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_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 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("worker_processes"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      0,
      offsetof(ngx_core_conf_t, worker_processes),
      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_sigpending"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      0,
      offsetof(ngx_core_conf_t, rlimit_sigpending),
      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 },

#if (NGX_THREADS)

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

    { ngx_string("thread_stack_size"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_size_slot,
      0,
      offsetof(ngx_core_conf_t, thread_stack_size),
      NULL },

#endif

      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;


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;

#if (NGX_FREEBSD)
    ngx_debug_init();
#endif

    /* TODO */ ngx_max_sockets = -1;

    ngx_time_init();

#if (NGX_PCRE)
    ngx_regex_init();
#endif

    ngx_pid = ngx_getpid();

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

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

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

    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_ERROR) {
        return 1;
    }

    if (ngx_getopt(&init_cycle, argc, ngx_argv) == NGX_ERROR) {
        return 1;
    }

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

    if (ngx_os_init(log) == NGX_ERROR) {
        return 1;
    }

    if (ngx_add_inherited_sockets(&init_cycle) == NGX_ERROR) {
        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_error(NGX_LOG_EMERG, log, 0,
                          "the configuration file %s test failed",
                          init_cycle.conf_file.data);
        }

        return 1;
    }

    if (ngx_test_config) {
        ngx_log_error(NGX_LOG_INFO, log, 0,
                      "the configuration file %s was tested successfully",
                      cycle->conf_file.data);
        return 0;
    }

    ngx_os_status(cycle->log);

    ngx_cycle = cycle;

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

    ngx_process = ccf->master ? NGX_PROCESS_MASTER : NGX_PROCESS_SINGLE;

#if (NGX_WIN32)

#if 0

    TODO:

    if (ccf->run_as_service) {
        if (ngx_service(cycle->log) == NGX_ERROR) {
            return 1;
        }

        return 0;
    }
#endif

#else

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

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

        ngx_daemonized = 1;
    }

    if (ngx_create_pidfile(cycle, NULL) == NGX_ERROR) {
        return 1;
    }

#endif

    if (ngx_process == NGX_PROCESS_MASTER) {
        ngx_master_process_cycle(cycle);

    } else {
        ngx_single_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_ERROR)
    {
        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);
}


ngx_pid_t
ngx_exec_new_binary(ngx_cycle_t *cycle, char *const *argv)
{
    char             *env[3], *var;
    u_char           *p;
    ngx_uint_t        i;
    ngx_pid_t         pid;
    ngx_exec_ctx_t    ctx;
    ngx_core_conf_t  *ccf;
    ngx_listening_t  *ls;

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

    var = ngx_alloc(sizeof(NGINX_VAR)
                    + cycle->listening.nelts * (NGX_INT32_LEN + 1) + 2,
                    cycle->log);

    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';

    ngx_log_debug1(NGX_LOG_DEBUG_CORE, cycle->log, 0, "inherited: %s", var);

    env[0] = var;

#if (NGX_SETPROCTITLE_USES_ENV)

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

    env[1] = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
             "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
             "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
             "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
             "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX";

    env[2] = NULL;

#else

    env[1] = NULL;

#endif

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

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

    if (ngx_rename_file((char *) ccf->pid.data, (char *) ccf->oldpid.data)
        != NGX_OK)
    {
        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(var);

        return NGX_INVALID_PID;
    }

    pid = ngx_execute(cycle, &ctx);

    if (pid == NGX_INVALID_PID) {
        if (ngx_rename_file((char *) ccf->oldpid.data, (char *) ccf->pid.data)
            != NGX_OK)
        {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          ngx_rename_file_n " %s back to %s failed "
                          "after try to executing new binary process \"%s\"",
                          ccf->oldpid.data, ccf->pid.data, argv[0]);
        }
    }

    ngx_free(var);

    return pid;
}


static ngx_int_t
ngx_getopt(ngx_cycle_t *cycle, int argc, char *const *argv)
{
    ngx_int_t  i;

    for (i = 1; i < argc; i++) {
        if (argv[i][0] != '-') {
            ngx_log_error(NGX_LOG_EMERG, cycle->log, 0,
                          "invalid option: \"%s\"", argv[i]);
            return NGX_ERROR;
        }

        switch (argv[i][1]) {

        case 't':
            ngx_test_config = 1;
            break;

        case 'c':
            if (argv[i + 1] == NULL) {
                ngx_log_error(NGX_LOG_EMERG, cycle->log, 0,
                              "the option: \"%s\" requires file name",
                              argv[i]);
                return NGX_ERROR;
            }

            cycle->conf_file.data = (u_char *) argv[++i];
            cycle->conf_file.len = ngx_strlen(cycle->conf_file.data);
            break;

        default:
            ngx_log_error(NGX_LOG_EMERG, cycle->log, 0,
                          "invalid option: \"%s\"", argv[i]);
            return NGX_ERROR;
        }
    }

    if (cycle->conf_file.data == NULL) {
        cycle->conf_file.len = sizeof(NGX_CONF_PATH) - 1;
        cycle->conf_file.data = (u_char *) NGX_CONF_PATH;
    }

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

    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

    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 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_sigpending = NGX_CONF_UNSET;

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

#if (NGX_THREADS)
    ccf->worker_threads = NGX_CONF_UNSET;
    ccf->thread_stack_size = NGX_CONF_UNSET_SIZE;
#endif

    return ccf;
}


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

#if !(NGX_WIN32)
    struct passwd    *pwd;
    struct group     *grp;
#endif

    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_SCHED_SETAFFINITY)

    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,
                      "number of the \"worker_processes\" is not equal to "
                      "the number of the \"worker_cpu_affinity\" mask, "
                      "using last mask for remaining worker processes");
    }

#endif

#if (NGX_THREADS)

    ngx_conf_init_value(ccf->worker_threads, 0);
    ngx_threads_n = ccf->worker_threads;
    ngx_conf_init_size_value(ccf->thread_stack_size, 2 * 1024 * 1024);

#endif

#if !(NGX_WIN32)

    if (ccf->user == (uid_t) NGX_CONF_UNSET_UINT && geteuid() == 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;

        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->pid.len == 0) {
        ccf->pid.len = sizeof(NGX_PID_PATH) - 1;
        ccf->pid.data = (u_char *) NGX_PID_PATH;
    }

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

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

    ccf->oldpid.data = ngx_palloc(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));

#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;

    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);

    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_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_SCHED_SETAFFINITY)
    ngx_core_conf_t  *ccf = conf;

    u_char            ch;
    u_long           *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(long));
    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 > 32) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                         "\"worker_cpu_affinity\" supports up to 32 CPU 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;
}


u_long
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];
}