Example #1
0
void
ngx_single_process_cycle(ngx_cycle_t *cycle)
{
    ngx_uint_t  i;

    if (ngx_set_environment(cycle, NULL) == NULL) {
        /* fatal */
        exit(2);
    }

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

    for ( ;; ) {
        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "worker cycle");

        ngx_process_events_and_timers(cycle);

        if (ngx_terminate || ngx_quit) {

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

            ngx_master_process_exit(cycle);
        }

        //平滑重启 
        if (ngx_reconfigure) {
            ngx_reconfigure = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reconfiguring");

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

            ngx_cycle = cycle;
        }

        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, (ngx_uid_t) -1);
        }
    }
}
Example #2
0
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;

    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));

    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "sigprocmask() failed");
    }

    sigemptyset(&set);


    size = sizeof(master_process);

    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    title = ngx_pnalloc(cycle->pool, size);

    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }

    ngx_setproctitle(title);


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

    ngx_start_worker_processes(cycle, ccf->worker_processes,
                               NGX_PROCESS_RESPAWN);
    ngx_start_cache_manager_processes(cycle, 0);

    ngx_new_binary = 0;
    delay = 0;
    sigio = 0;
    live = 1;

    for ( ;; ) {
        if (delay) {
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %d", delay);

            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;

            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");

        sigsuspend(&set);

        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);

        if (ngx_reap) {
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            live = ngx_reap_children(cycle);
        }

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

        if (ngx_terminate) {
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            sigio = ccf->worker_processes + 2 /* cache processes */;

            if (delay > 1000) {
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                ngx_signal_worker_processes(cycle,
                                       ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            continue;
        }

        if (ngx_quit) {
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) {
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        if (ngx_reconfigure) {
            ngx_reconfigure = 0;

            if (ngx_new_binary) {
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

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

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

            ngx_cycle = cycle;
            ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                   ngx_core_module);
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 1);

            /* allow new processes to start */
            ngx_msleep(100);

            live = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }

        if (ngx_restart) {
            ngx_restart = 0;
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 0);
            live = 1;
        }

        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }

        if (ngx_change_binary) {
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }

        if (ngx_noaccept) {
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    }
}
/*启动nginx,主要有以下几步工作:
1.主进程设置信号阻塞
2.设置进程标题
3.启动worker进程
4.启动缓存索引重建进程和管理进程
5.主进程循环处理信号
*/
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;

    //设置信号阻塞,屏蔽一系列信号,防止被打扰,具体见《apue》
    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));

    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "sigprocmask() failed");
    }

    sigemptyset(&set);


    size = sizeof(master_process);

    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    title = ngx_pnalloc(cycle->pool, size);

    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }
	//设置进程标题
    ngx_setproctitle(title);

    //master进程获取core模块配置,ccf中有要创建多少个worker的设定
    ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);

    //启动worker,这时已经有了worker进程
    ngx_start_worker_processes(cycle, ccf->worker_processes,            
                               NGX_PROCESS_RESPAWN);
    ngx_start_cache_manager_processes(cycle, 0);  //创建有关cache的子进程

	//信号处理是nginx服务器主进程在服务器运行期间的主要工作,通过一个for循环来实现对信号的循环处理。
    ngx_new_binary = 0;
    delay = 0;
    sigio = 0;
    live = 1;

    for ( ;; ) {
        //delay用来等待子进程退出的时间,由于我们接受到SIGINT信号后,我们需要先发送信号给子进程,
        //而子进程的退出需要一定的时间,超时时如果子进程已退出,我们父进程就直接退出,
        //否则发送sigkill信号给子进程(强制退出),然后再退出。  
        if (delay) {
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %d", delay);
			//初始化一个定时器
            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;

            //设置定时器
            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");

        //延时,等待信号
        sigsuspend(&set);  //调用这个将master进程挂起来

        ngx_time_update(); //更新缓冲时间

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);
        
        //ngx_reap为1,说明有子进程已经退出
        if (ngx_reap) {
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            //这个里面处理退出的子进程(有的worker异常退出,这时我们就需要重启这个worker ),如果所有子进程都退出则会返回0.  
            live = ngx_reap_children(cycle);
        }

        //如果没有存活的子进程,并且收到了ngx_terminate或者ngx_quit信号,则master退出。 
        if (!live && (ngx_terminate || ngx_quit)) {
            ngx_master_process_exit(cycle);   //master退出
        }
    
        //收到了sigint信号
        if (ngx_terminate) {
            //设置延时
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            sigio = ccf->worker_processes + 2 /* cache processes */;

            if (delay > 1000) {
                //如果超时,则强制杀死worker 
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                //负责发送sigint给worker,让它退出
                ngx_signal_worker_processes(cycle,
                                       ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            continue;
        }

        //收到quit信号
        if (ngx_quit) {
            //发送给worker quit信号
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) { //关闭所有socket
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        //收到需要reconfig的信号 
        if (ngx_reconfigure) {
            ngx_reconfigure = 0;

            //判断是否热代码替换后的新的代码还在运行中(也就是还没退出当前的master)。如果还在运行中,则不需要重新初始化config
			//ngx_new_binary表示程序本身需要升级,但不需要重新初始化nginx配置,直接调用ngx_start_wroker_process
            if (ngx_new_binary) {
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reconfiguring");
            
            //重新初始化config,并重新启动新的worker
            cycle = ngx_init_cycle(cycle);
            if (cycle == NULL) {
                cycle = (ngx_cycle_t *) ngx_cycle;
                continue;
            }

            ngx_cycle = cycle;
            ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                   ngx_core_module);
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 1);
            live = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }

        if (ngx_restart) {
            ngx_restart = 0;
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 0);
            live = 1;
        }

        //重新打开
        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }

        //热代码替换
        if (ngx_change_binary) {
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            //进行热代码替换,这里是调用execve来执行新的代码
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }

        //接受到停止accept连接,其实也就是worker退出(有区别的是,这里master不需要退出)
        if (ngx_noaccept) {
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            //给worker发送信号
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    } //end of for 信号处理结束
}
/*
 * 主要工作:
 * 主进程设置信号堵塞
 * 设置进程标题
 * 启动worker进程
 * 启动缓存索引重建(cache loader)进程及管理(Cache Manager)进程
 * 主进程循环处理信号
 * */
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;   /*保存的是等待工作进程退出的时间*/
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;

    /*将下列信号添加到信号集set中*/
    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));

    /*将信号集set覆盖为当前进程的信号集*/
    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
     "sigprocmask() failed");
    }

    sigemptyset(&set);


    /*开始设置进程标题*/
    /*计算进程标题的总体长度*/
    size = sizeof(master_process);

    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    title = ngx_pnalloc(cycle->pool, size);
    if (title == NULL) {
        /* fatal */
        exit(2);
    }

    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }

    /*设置进程标题*/
    ngx_setproctitle(title);

    /*获取核心模块上下文*/
    ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);

    /*启动工作进程*/
    ngx_start_worker_processes(cycle, ccf->worker_processes,
                               NGX_PROCESS_RESPAWN);
    /*启动缓存索引重建进程,该进程在整个Nginx服务器运行过程中只存在很短的时间,主要用来遍历磁盘上的缓存数据,在内存中建立数据索引,提高Nginx服务器检索缓存的效率*/
    ngx_start_cache_manager_processes(cycle, 0);

    ngx_new_binary = 0;
    delay = 0;
    sigio = 0;
    live = 1;

    for ( ;; ) {
        if (delay) {
            /*等待工作进程退出的时间*/
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %M", delay);

            /*初始化一个定时器*/
            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;

            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");

        /*挂起进程,等待接收到信号,在不向主进程发送信号的情况下,该进程将一直挂起在这里等待*/
        sigsuspend(&set);

        /*更新缓冲时间*/
        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);

        /*如果有工作进程异常退出,则调用ngx_reap_children()重启该工作进程*/
        if (ngx_reap) {
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            /*重启工作进程*/
            live = ngx_reap_children(cycle);
        }

        /*如果主进程接收到的是NGX_CMD_TERMINATE信号、SIGTERM信号、SIGINT信号(ngx_terminate=1)或者收到的是NGX_CMD_QUIT信号、SIGQUIT信号(ngx_quit=1),并且工作进程退出,则主进程调用ngx_master_process_exit()函数退出*/
        if (!live && (ngx_terminate || ngx_quit)) {
            ngx_master_process_exit(cycle);
        }

        /*处理SIGINT信号*/
        if (ngx_terminate) {
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            /*包括两个管理内存索引的进程*/
            sigio = ccf->worker_processes + 2 /* cache processes */;

            /*超时1s,直接终止工作进程*/
            if (delay > 1000) {
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                /*工作进程正常退出*/
                ngx_signal_worker_processes(cycle,
                                       ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            continue;
        }

        /*处理SIGQUIT信号*/
        if (ngx_quit) {
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            /*关闭所有的socket*/
            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) {
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        /*处理SIGHUP信号*/
        if (ngx_reconfigure) {
            ngx_reconfigure = 0;

            /*热升级(平滑升级,不用停止服务)*/
            /*当ngx_new_binary=1时,说明主进程本身需要升级,但是不需要重新初始化Nginx配置,因此可以直接调用ngx_start_worker_processes()函数重启工作进程和缓存索引管理进程*/
            /*当ngx_new_binary!=1时,则说明时Nginx服务器配置改变,需要调用ngx_init_cycle()函数初始化Nginx配置,并按照新的配置启动工作进程和缓存索引管理进程,向之前的所有进程发送NGX_SHUTDOWN_SIGNAL信号,这样旧实现了Nginx服务器的平滑升级*/
            if (ngx_new_binary) {
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

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

            /*建立信的cycle结构*/
            cycle = ngx_init_cycle(cycle);
            if (cycle == NULL) {
                cycle = (ngx_cycle_t *) ngx_cycle;
                continue;
            }

            /*读取Nginx配置*/
            ngx_cycle = cycle;
            ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                   ngx_core_module);
            /*创建工作进程*/
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            /*创建缓存管理进程*/
            ngx_start_cache_manager_processes(cycle, 1);

            /* allow new processes to start */
            ngx_msleep(100);

            live = 1;
            /*关闭旧的Nginx进程*/
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }

        /*重启工作进程*/
        /*只有一种情况可以将ngx_restart变量赋值为1,就是在调用ngx_reap_children()函数重启工作进程的时候,当主进程接收到NGX_NOACCEPT_SIGNAL信号(不再接收请求,退出工作进程)时,会设置全局变量ngx_noaccept为1,然后再Nginx初始化信号设置时会将全局变量ngx_noaccepting设置为1,于是在ngx_reap_children()函数中就会将ngx_restart变量设置为1,进而执行下面的if语句中的代码,重启工作进程和缓存索引管理进程*/
        if (ngx_restart) {
            ngx_restart = 0;
            /*启动工作进程*/
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            /*启动缓存索引管理进程刷新缓存索引*/
            ngx_start_cache_manager_processes(cycle, 0);
            live = 1;
        }

        /*处理SIGUSR1信号,该信号用于重新打开日志文件*/
        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }

        /*处理SIGUSR2信号,热代码切换*/
        if (ngx_change_binary) {
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }

        /*处理NGX_NOACCEPT_SIGNAL信号*/
        if (ngx_noaccept) {
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            /*退出工作进程,不再接收网络请求*/
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    }
}
Example #5
0
/*
 * master进程主循环
 */
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;

    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));
    /* 进程屏蔽set中的信号 */
    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "sigprocmask() failed");
    }

    sigemptyset(&set);


    size = sizeof(master_process);

    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    title = ngx_pnalloc(cycle->pool, size);
    if (title == NULL) {
        /* fatal */
        exit(2);
    }

    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }
    /* 修改进程名 */
    ngx_setproctitle(title);


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

    /* 启动work进程 */
    ngx_start_worker_processes(cycle, ccf->worker_processes,
                               NGX_PROCESS_RESPAWN);
    ngx_start_cache_manager_processes(cycle, 0);

    ngx_new_binary = 0;
    delay = 0;
    sigio = 0;
    live = 1;     /* 标记是否还有活着的子进程*/

    for ( ;; ) {
        //delay用来设置等待worker终止的时间,master接收了终止信号后
        //首先发送终止信号给worker,然后等待work终止
        if (delay) {
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %d", delay);

            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;
            /* 应为itv.it_interval 为0 定时器只触发一次 */
            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");
        /* 将进程的屏蔽信号集置空,然后进程挂起等待信号进入,信号处理程序处理完进入的信号后
           恢复屏蔽信号集,最后sigsuspend返回 */
        sigsuspend(&set);

        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);
        /* 当master收到work进程结束信号,回收子进程 */
        if (ngx_reap) {
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            live = ngx_reap_children(cycle);
        }
        /* live为1表示有子进程在运行,为0代表,所有子进程都退出了 */
        if (!live && (ngx_terminate || ngx_quit)) {
            /* 没有子进程了 且收到终止或退出信号*/
            ngx_master_process_exit(cycle);
        }
        /* master收到终止信号*/
        if (ngx_terminate) {
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            sigio = ccf->worker_processes + 2 /* cache processes */;

            if (delay > 1000) {
                /* 延时已到,给所有worker发送SIGKILL信号,强制杀死worker */
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                /* 通知work进程终止 */
                ngx_signal_worker_processes(cycle,
                                            ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            continue;
        }
        /* 通知工作线程退出,并关闭所有监听套接口 */
        if (ngx_quit) {
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) {
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        if (ngx_reconfigure) {
            ngx_reconfigure = 0;
            /* 代码已被替换,重启worker,不需要重新初始化配置。 */
            if (ngx_new_binary) {
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reconfiguring");
            //重新初始化配置
            cycle = ngx_init_cycle(cycle);
            if (cycle == NULL) {
                cycle = (ngx_cycle_t *) ngx_cycle;
                continue;
            }

            ngx_cycle = cycle;
            ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                   ngx_core_module);
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 1);

            /* allow new processes to start */
            ngx_msleep(100);

            live = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
        /* 重新创建work进程 当ngx_noaccepting==1时,会把ngx_restart设为1,重启worker */
        if (ngx_restart) {
            ngx_restart = 0;
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 0);
            live = 1;
        }
        /* 从新打开日志文件 */
        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }
        /* 热替换 */
        if (ngx_change_binary) {
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }
        /* 通知work进程停止accept新连接,work进程退出 */
        if (ngx_noaccept) {
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    }
}
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    u_long      nev, ev, timeout;
    ngx_err_t   err;
    ngx_int_t   n;
    ngx_msec_t  timer;
    ngx_uint_t  live;
    HANDLE      events[MAXIMUM_WAIT_OBJECTS];

    ngx_process_init(cycle);

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

    if (ngx_process == NGX_PROCESS_WORKER) {

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

        ngx_worker_process_cycle(cycle, ngx_master_process_event_name);
        return;
    }

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

    ngx_console_init(cycle);

    SetEnvironmentVariable("ngx_unique", ngx_unique);

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

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

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

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


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

//    ngx_close_listening_sockets(cycle);
    ngx_set_inherited_listen_sockets(cycle);

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

    timer = 0;
    timeout = INFINITE;

    for ( ;; ) {

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

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

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

        err = ngx_errno;
        ngx_time_update();

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

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

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

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

            ngx_terminate = 1;
            ngx_quit_worker_processes(cycle, 0);

            continue;
        }

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

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

            ngx_quit = 1;
            ngx_quit_worker_processes(cycle, 0);

            continue;
        }

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

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

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

            continue;
        }

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

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

			
/* 这个方案暂时已经可用了。不好的地方就是不能重启端口。如果端口配置有变化,就会有毛病。
			cycle = ngx_init_cycle(cycle);
			if (cycle == NULL) {
				cycle = (ngx_cycle_t *) ngx_cycle;
				continue;
			}

			ngx_cycle = cycle;

			//ngx_close_listening_sockets(cycle);

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

			/*---code 这里代码是先退掉所有工作进程,然后关闭listen 端口,再reload 配置,重启端口,重启工作进程*/
			ngx_quit_worker_processes(cycle, 0);
			ngx_close_listening_sockets(cycle);

			ngx_msleep(500);

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

			ngx_cycle = cycle;

			if (ngx_open_listening_sockets(cycle) != NGX_OK) {
				ngx_log_error(NGX_LOG_ALERT, cycle->log, err,
					"reload ngx_open_listening_sockets() failed");

				ngx_quit = 1;
				continue;
			}

			ngx_set_inherited_listen_sockets(cycle);

			if (ngx_start_worker_processes(cycle, NGX_PROCESS_RESPAWN) == 0) {
				exit(2);
			}
			/*---code --- end*/

            continue;
        }

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

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

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

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

            continue;
        }

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

            ngx_master_process_exit(cycle);
        }

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

            continue;
        }

        ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
            "WaitForMultipleObjects() returned unexpected value %ul", ev);
    }
}
Example #7
0
// http://www.xuebuyuan.com/557917.html
// http://blog.csdn.net/lu_ming/article/details/5144427
// http://blog.csdn.net/lengzijian/article/details/7587740
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;

    // block these signals
    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));

    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "sigprocmask() failed");
    }

    sigemptyset(&set);


    // set title = "master process" + argv[0] + argv[1] + ...
    size = sizeof(master_process);

    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    title = ngx_pnalloc(cycle->pool, size);

    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }

    ngx_setproctitle(title);


    // Start workers and cache_manager
    ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);

    ngx_start_worker_processes(cycle, ccf->worker_processes,
                               NGX_PROCESS_RESPAWN);
    ngx_start_cache_manager_processes(cycle, 0);

    ngx_new_binary = 0;
    delay = 0;
    sigio = 0;
    live = 1;

    for ( ;; ) {
        if (delay) {
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %d", delay);

            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;

            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");

        // sigsuspend() temporarily replaces the signal mask of the calling
        // process with the mask given by mask and then suspends the process 
        // until delivery of a signal whose action is to invoke a
        // signal handler or to terminate a process.
        sigsuspend(&set);

        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);

        if (ngx_reap) {
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            live = ngx_reap_children(cycle);
        }

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

        // on SIGINT set ngx_terminate = 1
        if (ngx_terminate) {
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            sigio = ccf->worker_processes + 2 /* cache processes */;

            if (delay > 1000) {
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                ngx_signal_worker_processes(cycle,
                                       ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            continue;
        }

        if (ngx_quit) {
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) {
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        if (ngx_reconfigure) {
            ngx_reconfigure = 0;

            if (ngx_new_binary) {
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

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

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

            ngx_cycle = cycle;
            ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                   ngx_core_module);
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 1);

            // Nginx won't guarantee the new workers will be ready to accept
            // new connections before sending shutdown signals to old workers.
            // If the new works takes more than 100ms to startup, then there is
            // a risk that the old workers are shutdown but new workers are still
            // not ready, as a result, new connections will be pending until a new
            // worker is ready to handle.
            /* allow new processes to start */
            ngx_msleep(100);

            live = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }

        if (ngx_restart) {
            ngx_restart = 0;
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 0);
            live = 1;
        }

        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }

        if (ngx_change_binary) {
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }

        if (ngx_noaccept) {
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    }
}
// main()函数里调用,仅启动一个进程,没有fork
// master_process off;
void
ngx_single_process_cycle(ngx_cycle_t *cycle)
{
    ngx_uint_t  i;

    if (ngx_set_environment(cycle, NULL) == NULL) {
        /* fatal */
        exit(2);
    }

    // 调用所有模块的init_process,即进程启动时hook
    for (i = 0; ngx_modules[i]; i++) {
        if (ngx_modules[i]->init_process) {
            if (ngx_modules[i]->init_process(cycle) == NGX_ERROR) {
                /* fatal */
                exit(2);
            }
        }
    }

    // 无限循环,对外提供服务
    // ngx_signal_handler处理unix信号
    // 收到信号后设置ngx_quit/ngx_sigalrm/ngx_reconfigue等全局变量
    // 由无限循环检查这些变量再处理
    for ( ;; ) {
        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "worker cycle");

        // 处理事件的核心函数, event模块里
        // 处理socket读写事件和定时器事件
        // 获取负载均衡锁,监听端口接受连接
        // 调用epoll模块的ngx_epoll_process_events
        // 然后处理超时事件和在延后队列里的所有事件
        // nginx大部分的工作量都在这里
        ngx_process_events_and_timers(cycle);

        // 检查是否处于退出状态
        // 这里不使用ngx_exiting变量,直接关闭端口退出
        if (ngx_terminate || ngx_quit) {

            // 所有模块的退出hook
            for (i = 0; ngx_modules[i]; i++) {
                if (ngx_modules[i]->exit_process) {
                    ngx_modules[i]->exit_process(cycle);
                }
            }

            // 删除pid,模块清理,关闭监听端口
            // 内部直接exit(0)退出
            ngx_master_process_exit(cycle);
        }

        // 重新配置,以当前cycle重新初始化,即reload
        if (ngx_reconfigure) {
            ngx_reconfigure = 0;    //标志量清零
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reconfiguring");

            // 以当前cycle重新初始化
            cycle = ngx_init_cycle(cycle);
            if (cycle == NULL) {
                cycle = (ngx_cycle_t *) ngx_cycle;
                continue;
            }

            ngx_cycle = cycle;
        }

        // 重新打开所有文件
        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, (ngx_uid_t) -1);
        }
    } // 无限循环,对外提供服务
}
// main()函数里调用,启动worker进程
// 监听信号
// 核心操作是sigsuspend,暂时挂起进程,不占用CPU,只有收到信号时才被唤醒
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;

    // 添加master进程关注的信号
    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));

    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "sigprocmask() failed");
    }

    sigemptyset(&set);


    // static u_char  master_process[] = "master process";
    // 计算master进程的名字
    size = sizeof(master_process);

    // 加上命令行参数,注意使用的是nginx拷贝后的参数
    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    // 分配名字的内存
    title = ngx_pnalloc(cycle->pool, size);
    if (title == NULL) {
        /* fatal */
        exit(2);
    }

    // 拷贝字符串
    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }

    // 设置进程名
    ngx_setproctitle(title);


    // 取core模块配置
    ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);

    // 启动worker进程,数量由配置决定,即worker_processes指令
    // #define NGX_PROCESS_RESPAWN       -3
    ngx_start_worker_processes(cycle, ccf->worker_processes,
                               NGX_PROCESS_RESPAWN);

    // cache进程
    ngx_start_cache_manager_processes(cycle, 0);

    ngx_new_binary = 0;
    delay = 0;      //延时的计数器
    sigio = 0;
    live = 1;       //是否有存活的子进程

    // master进程的无限循环,只处理信号
    // 主要调用ngx_signal_worker_processes()发送信号
    // ngx_start_worker_processes()产生新子进程
    for ( ;; ) {
        // 延时等待子进程关闭,每次进入加倍等待
        if (delay) {
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;     //延时加倍
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %d", delay);

            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;

            // 系统调用,设置发送SIGALRM的时间间隔
            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");

        // 核心操作是sigsuspend,暂时挂起进程,不占用CPU,只有收到信号时才被唤醒
        // 收到SIGALRM就检查子进程是否都已经处理完了
        sigsuspend(&set);

        // 更新一下时间
        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);

        // 子进程可能发生了意外结束
        // 在os/unix/ngx_process.c ngx_signal_handler()里设置
        if (ngx_reap) {
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            // 重新产生子进程
            live = ngx_reap_children(cycle);
        }

        // 无存活子进程且收到stop/quit信号
        if (!live && (ngx_terminate || ngx_quit)) {
            // 删除pid,模块清理,关闭监听端口
            // 内部直接exit(0)退出
            ngx_master_process_exit(cycle);
        }

        // 收到了-s stop,停止进程
        if (ngx_terminate) {
            // 延时等待子进程关闭
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            sigio = ccf->worker_processes + 2 /* cache processes */;

            if (delay > 1000) {
                // 超时太多,直接发送SIGKILL杀死进程
                // master进程调用,遍历ngx_processes数组,用kill发送信号
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                // master进程调用,遍历ngx_processes数组,用kill发送信号
                // 走到worker进程的ngx_signal_handler()
                // 然后再是ngx_worker_process_cycle()的ngx_terminate
                ngx_signal_worker_processes(cycle,
                                       ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            // 等待SIGALRM信号,检查子进程是否都结束
            continue;
        }

        // 收到了-s quit,关闭监听端口后再停止进程(优雅关闭)
        if (ngx_quit) {
            // master进程调用,遍历ngx_processes数组,用kill发送信号
            // 走到worker进程的ngx_signal_handler()
            // 然后再是ngx_worker_process_cycle()的ngx_quit
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            // 关闭所有监听端口
            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) {
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        // 收到了-s reload重新配置
        if (ngx_reconfigure) {
            ngx_reconfigure = 0;

            // 启动新的nginx二进制
            if (ngx_new_binary) {
                // 启动worker进程,数量由配置决定,即worker_processes指令
                // 调用时传递的是#define NGX_PROCESS_RESPAWN       -3
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

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

            // nginx可执行程序不变,以当前cycle重新初始化
            cycle = ngx_init_cycle(cycle);
            if (cycle == NULL) {
                cycle = (ngx_cycle_t *) ngx_cycle;
                continue;
            }

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

            // 启动worker进程,数量由配置决定,即worker_processes指令
            // 调用时传递的是#define NGX_PROCESS_JUST_RESPAWN       -2
            // 这样新启动的进程不会发送shutdown信号
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 1);

            /* allow new processes to start */
            // 阻塞等待100毫秒
            ngx_msleep(100);

            // 设置进程存活标志
            live = 1;

            // 关闭原来的worker进程
            // 新启动的进程不会发送shutdown信号
            // master进程调用,遍历ngx_processes数组,用kill发送信号
            // 走到worker进程的ngx_signal_handler()
            // 然后再是ngx_worker_process_cycle()的ngx_quit
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }

        if (ngx_restart) {
            ngx_restart = 0;

            // 启动worker进程,数量由配置决定,即worker_processes指令
            // 调用时传递的是#define NGX_PROCESS_RESPAWN       -3
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 0);

            // 设置进程存活标志
            live = 1;
        }

        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }

        if (ngx_change_binary) {
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }

        if (ngx_noaccept) {
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    }   //master进程无限循环结束
}
// 启动后master进程在这个函数进入死循环
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;

    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));

    // 让master进程只有在sigsuspend()里才会捕捉参数set里的信号。
    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "sigprocmask() failed");
    }

    sigemptyset(&set);


    // 设置ps命令显示的进程标题
    size = sizeof(master_process);

    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    title = ngx_pnalloc(cycle->pool, size);

    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }

    ngx_setproctitle(title);


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

    // 启动worker进程
    ngx_start_worker_processes(cycle, ccf->worker_processes,
                               NGX_PROCESS_RESPAWN);
    // 配置文件配置了相关功能时打开cache manager或cache loader进程,
    ngx_start_cache_manager_processes(cycle, 0);

    ngx_new_binary = 0;
    delay = 0;
    sigio = 0;
    live = 1;

    for ( ;; ) {
        if (delay) {
        // 收到退出信号后会使用这个分支,
        // 作用是定时检查是否还有活跃子进程,如果没有就退出master进程
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %d", delay);

            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;

            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");

        // 当没有收到信号时进程会在这个函数里休眠, 当收到信号后如果有信号处理函数先运行信号处理函数,
        // 然后向下运行。
        sigsuspend(&set);

        // 更新记录当前时间的全局变量。
        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);

        if (ngx_reap) {
        // master进程的子进程结束时,master进程收到SIGCHLD信号后,ngx_reap被置1。
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            live = ngx_reap_children(cycle);
        }

        if (!live && (ngx_terminate || ngx_quit)) {
        // 收到退出信号且已经没有活跃子进程后便退出
            ngx_master_process_exit(cycle);
        }

        if (ngx_terminate) {
        // 收到SIGINT,SIGTERM信号后,直接关闭nginx,
        // 首先给子进程发送关闭信号,1秒还没有关完就强制关闭所有子进程
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            sigio = ccf->worker_processes + 2 /* cache processes */;

            if (delay > 1000) {
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                ngx_signal_worker_processes(cycle,
                                       ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            continue;
        }

        if (ngx_quit) {
        // 收到SIGQUIT信号后,优雅关闭Nginx,
        // 待所有worker进程将已经连接的请求处理完后在退出
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) {
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        if (ngx_reconfigure) {
        // 收到SIGHUP信号后,ngx_reconfigure在信号处理函数中被置1,执行让新配置文件生效的操作。
            ngx_reconfigure = 0;

            if (ngx_new_binary) {
            // 在不重新载入配置文件的情况下启动工作进程。
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

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

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

            ngx_cycle = cycle;
            ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                   ngx_core_module);
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 1);

            /* allow new processes to start */
            ngx_msleep(100);

            live = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }

        if (ngx_restart) {
        // 好像是平滑升级时,新起的nginx意外退出了,要在把之前nginx的工作进程在重新启动
            ngx_restart = 0;
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 0);
            live = 1;
        }

        if (ngx_reopen) {
        // 重新打开日志文件
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }

        if (ngx_change_binary) {
        // 启动新的nignx,使新旧nginx同时工作
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }

        if (ngx_noaccept) {
        // 收到sigwinch信号后优雅关闭所有子进程
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    }
}
Example #11
0
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
    char              *title;
    u_char            *p;
    size_t             size;
    ngx_int_t          i;
    ngx_uint_t         n, sigio;
    sigset_t           set;
    struct itimerval   itv;
    ngx_uint_t         live;
    ngx_msec_t         delay;
    ngx_listening_t   *ls;
    ngx_core_conf_t   *ccf;
    struct rlimit     rlmt;

    sigemptyset(&set);
    sigaddset(&set, SIGCHLD);
    sigaddset(&set, SIGALRM);
    sigaddset(&set, SIGIO);
    sigaddset(&set, SIGINT);
    sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
    sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));

    if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "sigprocmask() failed");
    }

    sigemptyset(&set);


    size = sizeof(master_process);

    for (i = 0; i < ngx_argc; i++) {
        size += ngx_strlen(ngx_argv[i]) + 1;
    }

    title = ngx_pnalloc(cycle->pool, size);

    p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
    for (i = 0; i < ngx_argc; i++) {
        *p++ = ' ';
        p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
    }

    ngx_setproctitle(title);


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

    ngx_start_worker_processes(cycle, ccf->worker_processes,
                               NGX_PROCESS_RESPAWN);
    /* The directives such as "user", "rlimit_core", etc. should also be
     * effective on master process. Changed by Zimbra
     */
    if (ccf->rlimit_nofile != NGX_CONF_UNSET) {
        rlmt.rlim_cur = (rlim_t) ccf->rlimit_nofile;
        rlmt.rlim_max = (rlim_t) ccf->rlimit_nofile;

        if (setrlimit(RLIMIT_NOFILE, &rlmt) == -1) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "setrlimit(RLIMIT_NOFILE, %i) failed",
                          ccf->rlimit_nofile);
        }
    }

    if (ccf->rlimit_core != NGX_CONF_UNSET) {
        rlmt.rlim_cur = (rlim_t) ccf->rlimit_core;
        rlmt.rlim_max = (rlim_t) ccf->rlimit_core;

        if (setrlimit(RLIMIT_CORE, &rlmt) == -1) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "setrlimit(RLIMIT_CORE, %O) failed",
                          ccf->rlimit_core);
        }
    }

#ifdef RLIMIT_SIGPENDING
    if (ccf->rlimit_sigpending != NGX_CONF_UNSET) {
        rlmt.rlim_cur = (rlim_t) ccf->rlimit_sigpending;
        rlmt.rlim_max = (rlim_t) ccf->rlimit_sigpending;

        if (setrlimit(RLIMIT_SIGPENDING, &rlmt) == -1) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          "setrlimit(RLIMIT_SIGPENDING, %i) failed",
                          ccf->rlimit_sigpending);
        }
    }
#endif

    if (geteuid() == 0) {
        if (setgid(ccf->group) == -1) {
            ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
                          "setgid(%d) failed", ccf->group);
            /* fatal */
            exit(2);
        }

        if (initgroups(ccf->username, ccf->group) == -1) {
            ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
                          "initgroups(%s, %d) failed",
                          ccf->username, ccf->group);
        }

        if (setuid(ccf->user) == -1) {
            ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
                          "setuid(%d) failed", ccf->user);
            /* fatal */
            exit(2);
        }
    }
    /* end change by Zimbra */
    ngx_start_cache_manager_processes(cycle, 0);

    ngx_new_binary = 0;
    delay = 0;
    sigio = 0;
    live = 1;

    for ( ;; ) {
        if (delay) {
            if (ngx_sigalrm) {
                sigio = 0;
                delay *= 2;
                ngx_sigalrm = 0;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "termination cycle: %d", delay);

            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = delay / 1000;
            itv.it_value.tv_usec = (delay % 1000 ) * 1000;

            if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
                ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                              "setitimer() failed");
            }
        }

        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");

        sigsuspend(&set);

        ngx_time_update();

        ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                       "wake up, sigio %i", sigio);

        if (ngx_reap) {
            ngx_reap = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");

            live = ngx_reap_children(cycle);
        }

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

        if (ngx_terminate) {
            if (delay == 0) {
                delay = 50;
            }

            if (sigio) {
                sigio--;
                continue;
            }

            sigio = ccf->worker_processes + 2 /* cache processes */;

            if (delay > 1000) {
                ngx_signal_worker_processes(cycle, SIGKILL);
            } else {
                ngx_signal_worker_processes(cycle,
                                       ngx_signal_value(NGX_TERMINATE_SIGNAL));
            }

            continue;
        }

        if (ngx_quit) {
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));

            ls = cycle->listening.elts;
            for (n = 0; n < cycle->listening.nelts; n++) {
                if (ngx_close_socket(ls[n].fd) == -1) {
                    ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
                                  ngx_close_socket_n " %V failed",
                                  &ls[n].addr_text);
                }
            }
            cycle->listening.nelts = 0;

            continue;
        }

        if (ngx_reconfigure) {
            ngx_reconfigure = 0;

            if (ngx_new_binary) {
                ngx_start_worker_processes(cycle, ccf->worker_processes,
                                           NGX_PROCESS_RESPAWN);
                ngx_start_cache_manager_processes(cycle, 0);
                ngx_noaccepting = 0;

                continue;
            }

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

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

            ngx_cycle = cycle;
            ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                   ngx_core_module);
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_JUST_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 1);
            live = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }

        if (ngx_restart) {
            ngx_restart = 0;
            ngx_start_worker_processes(cycle, ccf->worker_processes,
                                       NGX_PROCESS_RESPAWN);
            ngx_start_cache_manager_processes(cycle, 0);
            live = 1;
        }

        if (ngx_reopen) {
            ngx_reopen = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
            ngx_reopen_files(cycle, ccf->user);
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_REOPEN_SIGNAL));
        }

        if (ngx_change_binary) {
            ngx_change_binary = 0;
            ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
            ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
        }

        if (ngx_noaccept) {
            ngx_noaccept = 0;
            ngx_noaccepting = 1;
            ngx_signal_worker_processes(cycle,
                                        ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
        }
    }
}