int ngx_cdecl main(int argc, char *const *argv) { ngx_buf_t *b; ngx_log_t *log; ngx_uint_t i; ngx_cycle_t *cycle, init_cycle; ngx_conf_dump_t *cd; 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_show_version_info(); 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); } if (ngx_dump_config) { cd = cycle->config_dump.elts; for (i = 0; i < cycle->config_dump.nelts; i++) { ngx_write_stdout("# configuration file "); (void) ngx_write_fd(ngx_stdout, cd[i].name.data, cd[i].name.len); ngx_write_stdout(":" NGX_LINEFEED); b = cd[i].buffer; (void) ngx_write_fd(ngx_stdout, b->pos, b->last - b->pos); ngx_write_stdout(NGX_LINEFEED); } } 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; }
int ngx_cdecl main(int argc, char *const *argv) { ngx_buf_t *b; ngx_log_t *log; ngx_uint_t i; ngx_cycle_t *cycle, init_cycle; ngx_conf_dump_t *cd; 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 [-?hvVtTq] [-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 " -T : test configuration, dump it 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); } if (ngx_dump_config) { cd = cycle->config_dump.elts; for (i = 0; i < cycle->config_dump.nelts; i++) { ngx_write_stdout("# configuration file "); (void) ngx_write_fd(ngx_stdout, cd[i].name.data, cd[i].name.len); ngx_write_stdout(":" NGX_LINEFEED); b = cd[i].buffer; (void) ngx_write_fd(ngx_stdout, b->pos, b->last - b->pos); ngx_write_stdout(NGX_LINEFEED); } } 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; }
// nginx启动的入口函数 // 相关文件ngx_process_cycle.c/ngx_posix_init.c/ngx_process.c // 设置重要的指针volatile ngx_cycle_t *ngx_cycle; // // 1)解析命令行参数,显示帮助信息 // 2)初始化操作系统调用接口函数ngx_os_io = ngx_linux_io; // 3)根据命令行参数等建立一个基本的cycle // 4)初始化模块数组ngx_modules // 5)核心操作,调用ngx_init_cycle创建进程使用的cycle,解析配置文件,启动监听端口 // 6)启动单进程或多进程 int ngx_cdecl main(int argc, char *const *argv) { ngx_buf_t *b; ngx_log_t *log; ngx_uint_t i; ngx_cycle_t *cycle, init_cycle; //cycle结构体 ngx_conf_dump_t *cd; ngx_core_conf_t *ccf; //获得ngx_core_module的配置结构体 ngx_debug_init(); if (ngx_strerror_init() != NGX_OK) { return 1; } // 解析命令行参数, 本文件内查找ngx_get_options // 设置ngx_show_version/ngx_show_help等变量 if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } // 1.9.x改到ngx_show_version_info() if (ngx_show_version) { ngx_show_version_info(); // 1.9.x ngx_show_version_info()结束 if (!ngx_test_config) { //如果是-t参数,那么接下来要走流程检查配置但不启动 return 0; } } // 在ngx_os_init函数里设置(os/unix/ngx_posix_init.c) // 使用系统调用getrlimit(RLIMIT_NOFILE, &rlmt) // 是nginx能够打开的最多描述数量,但似乎并没有使用 /* TODO */ ngx_max_sockets = -1; // ngx_times.c,初始化各个cache时间变量 // 调用ngx_time_update(),得到当前的时间 ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); // 正则表达式库初始化 #endif // 定义在os/unix/ngx_process_cycle.c : ngx_pid_t ngx_pid; // ngx_process.h : #define ngx_getpid getpid // 获取当前进程也就是master进程的pid // 如果是master/worker,会fork出新的子进程,见os/unix/ngx_daemon.c ngx_pid = ngx_getpid(); // 初始化log // ngx_prefix是-p后的参数,即nginx的工作目录 // 默认是NGX_CONF_PREFIX,即/usr/local/nginx 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() */ // 设置最开始的cycle ngx_memzero(&init_cycle, sizeof(ngx_cycle_t)); init_cycle.log = log; // 定义在ngx_cycle.c, // volatile ngx_cycle_t *ngx_cycle; // nginx生命周期使用的超重要对象 // ngx_cycle指针指向第一个cycle结构体 ngx_cycle = &init_cycle; //创建cycle使用的内存池,用于之后所有的内存分配,必须成功 init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } // 分配内存,拷贝参数,没有使用内存池 // 拷贝到全局变量ngx_argc/ngx.argv if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } // 设置cycle->prefix/cycle->conf_prefix等成员 if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } // os/unix/ngx_posix_init.c // 初始化ngx_os_io结构体,设置基本的收发函数 // 基本的页大小,ngx_pagesize = getpagesize() // 最多描述符数量,ngx_max_sockets // 初始化随机数 // ngx_os_io = ngx_linux_io;重要的操作,设置为linux的接口函数 if (ngx_os_init(log) != NGX_OK) { return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() */ // 初始化用于crc32计算的表,在ngx_crc32.c if (ngx_crc32_table_init() != NGX_OK) { return 1; } // 检查NGINX环境变量,获取之前监听的socket if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } // 开始计算所有的静态模块数量 // ngx_modules是nginx模块数组,存储所有的模块指针,由make生成在objs/ngx_modules.c // 这里赋值每个模块的index成员 // ngx_modules_n保存了最后一个可用的序号 // ngx_max_module是模块数量的上限 if (ngx_preinit_modules() != NGX_OK) { return 1; } // ngx_cycle.c // 初始化cycle,800多行 // 由之前最基本的init_cycle产生出真正使用的cycle // 解析配置文件,配置所有的模块 // 创建共享内存,打开文件,监听配置的端口 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; } // 如果用了-t参数要测试配置,在这里就结束了 // 定义在ngx_cycle.c if (ngx_test_config) { //非安静模式,输出测试信息 if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } // 1.10, dump整个配置文件 if (ngx_dump_config) { cd = cycle->config_dump.elts; for (i = 0; i < cycle->config_dump.nelts; i++) { ngx_write_stdout("# configuration file "); (void) ngx_write_fd(ngx_stdout, cd[i].name.data, cd[i].name.len); ngx_write_stdout(":" NGX_LINEFEED); b = cd[i].buffer; (void) ngx_write_fd(ngx_stdout, b->pos, b->last - b->pos); ngx_write_stdout(NGX_LINEFEED); } } return 0; } // 如果用了-s参数,那么就要发送reload/stop等信号,然后结束 if (ngx_signal) { // ngx_cycle.c // 最后调用os/unix/ngx_process.c里的函数ngx_os_signal_process() return ngx_signal_process(cycle, ngx_signal); } // ngx_posix_init.c // 使用NGX_LOG_NOTICE记录操作系统的一些信息,通常不会显示 ngx_os_status(cycle->log); // 定义在ngx_cycle.c, // volatile ngx_cycle_t *ngx_cycle; // nginx生命周期使用的超重要对象 ngx_cycle = cycle; // 检查core模块的配置 ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); // master on且单进程 // 如果master_process off那么就不是master进程 // ngx_process定义在os/unix/ngx_process_cycle.c if (ccf->master && ngx_process == NGX_PROCESS_SINGLE) { // 设置为master进程状态 ngx_process = NGX_PROCESS_MASTER; } // unix/linux将进程守护进程化 #if !(NGX_WIN32) // os/unix/ngx_process.c // 使用signals数组,初始化信号处理handler if (ngx_init_signals(cycle->log) != NGX_OK) { return 1; } // 守护进程 if (!ngx_inherited && ccf->daemon) { // os/unix/ngx_daemon.c // 经典的daemon操作,使用fork if (ngx_daemon(cycle->log) != NGX_OK) { return 1; } ngx_daemonized = 1; } if (ngx_inherited) { ngx_daemonized = 1; } #endif // ngx_cycle.c // 把ngx_pid字符串化,写入pid文件 // 在daemon后,此时的pid是真正的master进程pid 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; // 启动单进程或者master/worker多进程,内部会调用fork // 子进程完全复制父进程的cycle,包括打开的文件、共享内存、监听的端口 if (ngx_process == NGX_PROCESS_SINGLE) { // 如果master_process off那么就不是master进程 // ngx_process_cycle.c ngx_single_process_cycle(cycle); } else { // ngx_process_cycle.c // 启动worker进程,数量由配置决定,即worker_processes指令 // 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 ngx_master_process_cycle(cycle); } // 只有退出无限循环才会走到这里,进程结束 return 0; }
/* * __cdecl表示C语言默认的函数调用方法,即所有参数从右到左依次入栈,这些参数有调用者负责清除,被调用函数不会要求 * 调用者传递多少参数,调用者传递过多或过少的参数都不会引起编译错误。 */ int ngx_cdecl main(int argc, char *const *argv) { ngx_buf_t *b; ngx_log_t *log; ngx_uint_t i; ngx_cycle_t *cycle, init_cycle; ngx_conf_dump_t *cd; ngx_core_conf_t *ccf; ngx_debug_init(); //设置全局变量ngx_debug_malloc /*初始化系统错误码对应的描述性字符串*/ if (ngx_strerror_init() != NGX_OK) { return 1; } /*ngx_get_options()函数用于解析命令行参数,并设置命令行参数相应的标志位*/ if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } /*根据ngx_get_options()函数中设置的标志位打印相关信息到标准输出上*/ if (ngx_show_version) { ngx_show_version_info(); if (!ngx_test_config) { return 0; } } /* TODO */ ngx_max_sockets = -1; /*初始化并更新nginx内核使用的时间*/ ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); #endif /*获取master进程ID*/ ngx_pid = ngx_getpid(); /*初始化全局错误日志对象ngx_log及前缀ngx_prefix*/ 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; /*为进程唯一核心结构体ngx_cycle_t的创建内存池*/ init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } /*保存命令行参数*/ if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } /*ngx_process_options()用于初始化ngx_cycle的prefix, conf_prefix, conf_file, conf_param等*/ if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } /*对Nginx内核中用到的一些和操作系统相关性大的全局变量进行初始化*/ if (ngx_os_init(log) != NGX_OK) { return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() */ /*初始化循环冗余校验表,后续校验可以直接通过查表法*/ if (ngx_crc32_table_init() != NGX_OK) { return 1; } /*平滑升级时新版本master进程对旧版本master进程的监听句柄做继承处理*/ if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } /*ngx_preinit_modules()初始化模块的一些信息和部分相关全局变量*/ if (ngx_preinit_modules() != NGX_OK) { return 1; } /*初始化全局唯一的ngx_cycle_t*/ 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); } if (ngx_dump_config) { cd = cycle->config_dump.elts; for (i = 0; i < cycle->config_dump.nelts; i++) { ngx_write_stdout("# configuration file "); (void) ngx_write_fd(ngx_stdout, cd[i].name.data, cd[i].name.len); ngx_write_stdout(":" NGX_LINEFEED); b = cd[i].buffer; (void) ngx_write_fd(ngx_stdout, b->pos, b->last - b->pos); ngx_write_stdout(NGX_LINEFEED); } } return 0; } /*"nginx -s xxx"*/ 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) /*初始化信号*/ 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 /*创建pidfile,并写入当前进程id*/ if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } if (ngx_log_redirect_stderr(cycle) != NGX_OK) { return 1; } /*关闭日志文件流*/ 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; /*单进程模式运行*/ if (ngx_process == NGX_PROCESS_SINGLE) { ngx_single_process_cycle(cycle); } else { /*以一个master进程多个woker进程运行*/ ngx_master_process_cycle(cycle); } return 0; }
//1.时间、正则、错误日志、ssl等初始化 //2.读入命令行参数 //3.OS相关初始化 //4.读入并解析配置 //5.核心模块初始化 //6.创建各种临时文件和目录 //7.创建共享内存 //8.打开listen的端口 //9.所有模块初始化 //10.启动worker进程 //全书内容可以在http://book.2cto.com/201304/19606.html中查看,可以直接复制注释 int ngx_cdecl main(int argc, char *const *argv) { ngx_buf_t *b; ngx_log_t *log; ngx_uint_t i; ngx_cycle_t *cycle, init_cycle; ngx_conf_dump_t *cd; ngx_core_conf_t *ccf; ngx_debug_init(); if (ngx_strerror_init() != NGX_OK) { return 1; } //获取参数和配置参数,比如命令是nginx -v 那么ngx_show_version就设置为1 if (ngx_get_options(argc, argv) != NGX_OK) { //解析命令参数 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 [-?hvVtTq] [-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" //除了version外还可以显示操作系统和configure阶段等相关信息 NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED //不启动nginx进程,只是测试配置文件是否有错误 " -T : test configuration, dump it and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED //通过-t测试配置文件是否错误的时候,nginx -t -q可以把error级别以下的日志不输出的屏幕 " -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 //指定安装目录 #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED //指定配置文件 " -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(); //初始化nginx环境的当前时间 #if (NGX_PCRE) ngx_regex_init(); #endif ngx_pid = ngx_getpid(); /* 主进程启动的时候,此时还没有读取配置文件,即没有指定日志打印在哪里。nginx这时候虽然可以将一些出错内容或者结果输到标准输出,但是如果要记录一些系统初始化情况, socket监听状况,还是需要写到日志文件中去的。在nginx的main函数中,首先会调用ngx_log_init 函数,默认日志文件为:安装路径/logs/error.log,如果这个文件没有权限访问的话, 会直接报错退出。在mian函数结尾处,在ngx_master_process_cycle函数调用之前,会close掉这个日志文件。 */ 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); } if (ngx_dump_config) { cd = cycle->config_dump.elts; for (i = 0; i < cycle->config_dump.nelts; i++) { ngx_write_stdout("# configuration file "); (void) ngx_write_fd(ngx_stdout, cd[i].name.data, cd[i].name.len); ngx_write_stdout(":" NGX_LINEFEED); b = cd[i].buffer; (void) ngx_write_fd(ngx_stdout, b->pos, b->last - b->pos); ngx_write_stdout(NGX_LINEFEED); } } return 0; } /* 如果hginx.conf中配置为单进程工作模式,这时将会调用ngx_single_process_cycle方法进入单迸程工作模式。 */ if (ngx_signal) { //加了-S参数 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) { //在这里会把进程模式设置为MASTER模式 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) { //前面的log = ngx_log_init(ngx_prefix); 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) { //如果配置的是单进程工作模式,好像不会走到这里 ngx_single_process_cycle(cycle); } else { //一般都是走到这里,master方式 ngx_master_process_cycle(cycle); } return 0; }