int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; ngx_debug_init(); if (ngx_strerror_init() != NGX_OK) { return 1; } if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } /* TODO */ ngx_max_sockets = -1; ngx_time_init(); ngx_pid = ngx_getpid(); log = ngx_log_init(ngx_prefix); if (log == NULL) { return 1; } /* STUB */ /* * init_cycle->log is required for signal handlers and * ngx_process_options() */ ngx_memzero(&init_cycle, sizeof(ngx_cycle_t)); init_cycle.log = log; ngx_cycle = &init_cycle; init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } if (ngx_os_init(log) != NGX_OK) { return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() */ if (ngx_crc32_table_init() != NGX_OK) { return 1; } if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { ngx_modules[i]->index = ngx_max_module++; } cycle = ngx_init_cycle(&init_cycle); if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } if (ngx_signal) { return ngx_signal_process(cycle, ngx_signal); } ngx_os_status(cycle->log); ngx_cycle = cycle; ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ccf->master && ngx_process == NGX_PROCESS_SINGLE) { ngx_process = NGX_PROCESS_MASTER; } // if (ngx_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; // } 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_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; ngx_debug_init(); if (ngx_strerror_init() != NGX_OK) { //初始化错误编号的错误字符串数组 return 1; } if (ngx_get_options(argc, argv) != NGX_OK) { //命令行处理 return 1; } //如果ngx_show_version由上面的ngx_get_options置为1 if (ngx_show_version) { ngx_write_stderr("nginx version: " NGINX_VER_BUILD NGX_LINEFEED); //显示宏定义 if (ngx_show_help) { ngx_write_stderr( "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" NGX_LINEFEED NGX_LINEFEED "Options:" NGX_LINEFEED " -?,-h : this help" NGX_LINEFEED " -v : show version and exit" NGX_LINEFEED " -V : show version and configure options then exit" NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED " -s signal : send signal to a master process: " "stop, quit, reopen, reload" NGX_LINEFEED #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" NGX_LINEFEED #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED " -g directives : set global directives out of configuration " "file" NGX_LINEFEED NGX_LINEFEED ); } if (ngx_show_configure) { #ifdef NGX_COMPILER ngx_write_stderr("built by " NGX_COMPILER NGX_LINEFEED); #endif #if (NGX_SSL) if (SSLeay() == SSLEAY_VERSION_NUMBER) { ngx_write_stderr("built with " OPENSSL_VERSION_TEXT NGX_LINEFEED); } else { ngx_write_stderr("built with " OPENSSL_VERSION_TEXT " (running with "); ngx_write_stderr((char *) (uintptr_t) SSLeay_version(SSLEAY_VERSION)); ngx_write_stderr(")" NGX_LINEFEED); } #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME ngx_write_stderr("TLS SNI support enabled" NGX_LINEFEED); #else ngx_write_stderr("TLS SNI support disabled" NGX_LINEFEED); #endif #endif ngx_write_stderr("configure arguments:" NGX_CONFIGURE NGX_LINEFEED); } if (!ngx_test_config) { return 0; } } /* TODO */ ngx_max_sockets = -1; ngx_time_init(); //时间初始化 #if (NGX_PCRE) ngx_regex_init(); #endif ngx_pid = ngx_getpid(); //获得主进程pid log = ngx_log_init(ngx_prefix); //初始化log 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() */ //构造一个init_cycle,旧的预处理 ngx_memzero(&init_cycle, sizeof(ngx_cycle_t)); init_cycle.log = log; ngx_cycle = &init_cycle; //init_cycle是在栈中的 init_cycle.pool = ngx_create_pool(1024, log); //1K大小内存 if (init_cycle.pool == NULL) { return 1; } //拷贝一份argv if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } //处理命令行选项 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; } //从环境变量中继承一些监听描述符,用于平滑升级 if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } //设置模块的编号,从0开始计数 ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { ngx_modules[i]->index = ngx_max_module++; } cycle = ngx_init_cycle(&init_cycle); //创建新的cycle if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } if (ngx_signal) { //如果要向指定的进程发送信号 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; //以多进程方式工作 } #if !(NGX_WIN32) if (ngx_init_signals(cycle->log) != NGX_OK) { //初始化信号相关操作 return 1; } if (!ngx_inherited && ccf->daemon) { if (ngx_daemon(cycle->log) != NGX_OK) { //以守护进程来运行 return 1; } ngx_daemonized = 1; } if (ngx_inherited) { ngx_daemonized = 1; } #endif //创建进程的pid的文件 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); //以多进程方式运行 } return 0; }
ngx_cycle_t * ngx_init_cycle(ngx_cycle_t *old_cycle) { void *rv; char **senv, **env; ngx_uint_t i, n; ngx_log_t *log; ngx_time_t *tp; ngx_conf_t conf; ngx_pool_t *pool; ngx_cycle_t *cycle, **old; ngx_shm_zone_t *shm_zone, *oshm_zone; ngx_list_part_t *part, *opart; ngx_open_file_t *file; ngx_listening_t *ls, *nls; ngx_core_conf_t *ccf, *old_ccf; ngx_core_module_t *module; char hostname[NGX_MAXHOSTNAMELEN]; ngx_timezone_update(); /* force localtime update with a new timezone */ tp = ngx_timeofday(); tp->sec = 0; // 这会导致秒级时间流逝而强制更新所有时间数据 ngx_time_update(); log = old_cycle->log; // 创建内存池,然后在内存池中创建cycle,再将该内存池挂到cycle上 pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (pool == NULL) { return NULL; } pool->log = log; cycle = ngx_pcalloc(pool, sizeof(ngx_cycle_t)); if (cycle == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pool = pool; cycle->log = log; cycle->new_log.log_level = NGX_LOG_ERR; cycle->old_cycle = old_cycle; // 配置前缀 cycle->conf_prefix.len = old_cycle->conf_prefix.len; cycle->conf_prefix.data = ngx_pstrdup(pool, &old_cycle->conf_prefix); if (cycle->conf_prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } // 通用前缀 cycle->prefix.len = old_cycle->prefix.len; cycle->prefix.data = ngx_pstrdup(pool, &old_cycle->prefix); if (cycle->prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } // 配置文件 cycle->conf_file.len = old_cycle->conf_file.len; cycle->conf_file.data = ngx_pnalloc(pool, old_cycle->conf_file.len + 1); if (cycle->conf_file.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_cpystrn(cycle->conf_file.data, old_cycle->conf_file.data, old_cycle->conf_file.len + 1); // 配置参数 cycle->conf_param.len = old_cycle->conf_param.len; cycle->conf_param.data = ngx_pstrdup(pool, &old_cycle->conf_param); if (cycle->conf_param.data == NULL) { ngx_destroy_pool(pool); return NULL; } // 路径数组,每个元素是一个数组指针 n = old_cycle->pathes.nelts ? old_cycle->pathes.nelts : 10; cycle->pathes.elts = ngx_pcalloc(pool, n * sizeof(ngx_path_t *)); if (cycle->pathes.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pathes.nelts = 0; cycle->pathes.size = sizeof(ngx_path_t *); cycle->pathes.nalloc = n; cycle->pathes.pool = pool; // 获取打开的文件数目 if (old_cycle->open_files.part.nelts) { // 统计链表所有元素个数 n = old_cycle->open_files.part.nelts; for (part = old_cycle->open_files.part.next; part; part = part->next) { n += part->nelts; } } else { n = 20; } // 初始化新打开的文件列表,ngx_open_file_t的结构很简单,只有 // fd, name,文件头尾指针及位置指针 if (ngx_list_init(&cycle->open_files, pool, n, sizeof(ngx_open_file_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } // 共享内存的初始化类似于上面打开文件的初始化 if (old_cycle->shared_memory.part.nelts) { n = old_cycle->shared_memory.part.nelts; for (part = old_cycle->shared_memory.part.next; part; part = part->next) { n += part->nelts; } } else { n = 1; } if (ngx_list_init(&cycle->shared_memory, pool, n, sizeof(ngx_shm_zone_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } // 监听数组 n = old_cycle->listening.nelts ? old_cycle->listening.nelts : 10; cycle->listening.elts = ngx_pcalloc(pool, n * sizeof(ngx_listening_t)); if (cycle->listening.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->listening.nelts = 0; cycle->listening.size = sizeof(ngx_listening_t); cycle->listening.nalloc = n; cycle->listening.pool = pool; // 可重用连接队列 ngx_queue_init(&cycle->reusable_connections_queue); // 创建模块配置数组列表,每个元素是一个指针, // 指向保存了模块的配置对象的create_conf回调创建的配置 cycle->conf_ctx = ngx_pcalloc(pool, ngx_max_module * sizeof(void *)); if (cycle->conf_ctx == NULL) { ngx_destroy_pool(pool); return NULL; } // 初始化主机名 if (gethostname(hostname, NGX_MAXHOSTNAMELEN) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "gethostname() failed"); ngx_destroy_pool(pool); return NULL; } /* on Linux gethostname() silently truncates name that does not fit */ hostname[NGX_MAXHOSTNAMELEN - 1] = '\0'; cycle->hostname.len = ngx_strlen(hostname); cycle->hostname.data = ngx_pnalloc(pool, cycle->hostname.len); if (cycle->hostname.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_strlow(cycle->hostname.data, (u_char *) hostname, cycle->hostname.len); // 创建核心模块配置,通过调用模块的create_conf函数 for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } // 这个ctx是与模块类型相关的 // 比如NGX_CORE_MODULE类型的模块就是ngx_core_module_t类型 module = ngx_modules[i]->ctx; // ngx_core_module_t的create_conf函数 // 它会创建一个ngx_core_conf_t类型的对象 if (module->create_conf) { // ngx_core_module_t的create_conf函数 rv = module->create_conf(cycle); if (rv == NULL) { ngx_destroy_pool(pool); return NULL; } // conf_ctx现在指向模块配置数组 // 对于核心模块来说,元素指针指向ngx_core_module_t.create_conf函 // 数创建的ngx_core_conf_t类型的对象,给之 // 后的ngx_core_module_t.init_conf函数初始化 cycle->conf_ctx[ngx_modules[i]->index] = rv; } } senv = environ; // 初始化conf ngx_memzero(&conf, sizeof(ngx_conf_t)); /* STUB: init array ? */ // 配置命令字符串数组 conf.args = ngx_array_create(pool, 10, sizeof(ngx_str_t)); if (conf.args == NULL) { ngx_destroy_pool(pool); return NULL; } conf.temp_pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (conf.temp_pool == NULL) { ngx_destroy_pool(pool); return NULL; } conf.ctx = cycle->conf_ctx; // 接管模块配置数组 conf.cycle = cycle; conf.pool = pool; // 挂上cycle的内存池 conf.log = log; conf.module_type = NGX_CORE_MODULE; conf.cmd_type = NGX_MAIN_CONF; // 命令类型 #if 0 log->log_level = NGX_LOG_DEBUG_ALL; #endif // ngx_conf_param函数让ngx_conf_t类型的对象conf挂一个 // 临时的ngx_conf_file_t,再去调用ngx_conf_parse函数解 // 析用户指定的配置参数(cycle->conf_param),ngx_conf_parse函数 // 会以parse_param(还有parse_file和parse_block两种方式)方式执行解析循环 if (ngx_conf_param(&conf) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } // 解析配置文件 if (ngx_conf_parse(&conf, &cycle->conf_file) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_test_config && !ngx_quiet_mode) { ngx_log_stderr(0, "the configuration file %s syntax is ok", cycle->conf_file.data); } // 调用ngx_core_module_t的init_conf函数初始化 for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } module = ngx_modules[i]->ctx; // ngx_core_module_t if (module->init_conf) { if (module->init_conf(cycle, cycle->conf_ctx[ngx_modules[i]->index]) == NGX_CONF_ERROR) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } } } if (ngx_process == NGX_PROCESS_SIGNALLER) { // 进程角色是信号发送者,比如nginx -s可以停止已有的nginx进程 return cycle; } // 就是cycle->conf_ctx[ngx_modules[i]->index],ngx_core_conf_t类型 ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ngx_test_config) { if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } } else if (!ngx_is_init_cycle(old_cycle)) { /* * we do not create the pid file in the first ngx_init_cycle() call * because we need to write the demonized process pid */ old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (ccf->pid.len != old_ccf->pid.len || ngx_strcmp(ccf->pid.data, old_ccf->pid.data) != 0) { /* new pid file name */ if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } ngx_delete_pidfile(old_cycle); } } // 测试锁文件 if (ngx_test_lockfile(cycle->lock_file.data, log) != NGX_OK) { goto failed; } // 创建目录 if (ngx_create_pathes(cycle, ccf->user) != NGX_OK) { goto failed; } // 创建新的日志文件 if (cycle->new_log.file == NULL) { cycle->new_log.file = ngx_conf_open_file(cycle, &error_log); if (cycle->new_log.file == NULL) { goto failed; } } /* open the new files */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].name.len == 0) { continue; } file[i].fd = ngx_open_file(file[i].name.data, NGX_FILE_APPEND, NGX_FILE_CREATE_OR_OPEN, NGX_FILE_DEFAULT_ACCESS); ngx_log_debug3(NGX_LOG_DEBUG_CORE, log, 0, "log: %p %d \"%s\"", &file[i], file[i].fd, file[i].name.data); if (file[i].fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_open_file_n " \"%s\" failed", file[i].name.data); goto failed; } #if !(NGX_WIN32) if (fcntl(file[i].fd, F_SETFD, FD_CLOEXEC) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "fcntl(FD_CLOEXEC) \"%s\" failed", file[i].name.data); goto failed; } #endif } cycle->log = &cycle->new_log; pool->log = &cycle->new_log; /* create shared memory */ part = &cycle->shared_memory.part; shm_zone = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; i = 0; } if (shm_zone[i].shm.size == 0) { ngx_log_error(NGX_LOG_EMERG, log, 0, "zero size shared memory zone \"%V\"", &shm_zone[i].shm.name); goto failed; } shm_zone[i].shm.log = cycle->log; opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (n = 0; /* void */ ; n++) { if (n >= opart->nelts) { if (opart->next == NULL) { break; } opart = opart->next; oshm_zone = opart->elts; n = 0; } if (shm_zone[i].shm.name.len != oshm_zone[n].shm.name.len) { continue; } if (ngx_strncmp(shm_zone[i].shm.name.data, oshm_zone[n].shm.name.data, shm_zone[i].shm.name.len) != 0) { continue; } if (shm_zone[i].shm.size == oshm_zone[n].shm.size) { shm_zone[i].shm.addr = oshm_zone[n].shm.addr; if (shm_zone[i].init(&shm_zone[i], oshm_zone[n].data) != NGX_OK) { goto failed; } goto shm_zone_found; } ngx_shm_free(&oshm_zone[n].shm); break; } if (ngx_shm_alloc(&shm_zone[i].shm) != NGX_OK) { goto failed; } if (ngx_init_zone_pool(cycle, &shm_zone[i]) != NGX_OK) { goto failed; } if (shm_zone[i].init(&shm_zone[i], NULL) != NGX_OK) { goto failed; } shm_zone_found: continue; } /* handle the listening sockets */ if (old_cycle->listening.nelts) { ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { ls[i].remain = 0; } nls = cycle->listening.elts; for (n = 0; n < cycle->listening.nelts; n++) { for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].ignore) { continue; } if (ngx_cmp_sockaddr(nls[n].sockaddr, ls[i].sockaddr) == NGX_OK) { nls[n].fd = ls[i].fd; nls[n].previous = &ls[i]; ls[i].remain = 1; if (ls[n].backlog != nls[i].backlog) { nls[n].listen = 1; } #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) /* * FreeBSD, except the most recent versions, * could not remove accept filter */ nls[n].deferred_accept = ls[i].deferred_accept; if (ls[i].accept_filter && nls[n].accept_filter) { if (ngx_strcmp(ls[i].accept_filter, nls[n].accept_filter) != 0) { nls[n].delete_deferred = 1; nls[n].add_deferred = 1; } } else if (ls[i].accept_filter) { nls[n].delete_deferred = 1; } else if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[n].deferred_accept && !nls[n].deferred_accept) { nls[n].delete_deferred = 1; } else if (ls[i].deferred_accept != nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif break; } } if (nls[n].fd == -1) { nls[n].open = 1; } } } else { ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { ls[i].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (ls[i].accept_filter) { ls[i].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept) { ls[i].add_deferred = 1; } #endif } } if (ngx_open_listening_sockets(cycle) != NGX_OK) { goto failed; } if (!ngx_test_config) { ngx_configure_listening_sockets(cycle); } /* commit the new cycle configuration */ if (!ngx_use_stderr && cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); } } pool->log = cycle->log; for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->init_module) { if (ngx_modules[i]->init_module(cycle) != NGX_OK) { /* fatal */ exit(1); } } } /* close and delete stuff that lefts from an old cycle */ /* free the unnecessary shared memory */ opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (i = 0; /* void */ ; i++) { if (i >= opart->nelts) { if (opart->next == NULL) { goto old_shm_zone_done; } opart = opart->next; oshm_zone = opart->elts; i = 0; } part = &cycle->shared_memory.part; shm_zone = part->elts; for (n = 0; /* void */ ; n++) { if (n >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; n = 0; } if (oshm_zone[i].shm.name.len == shm_zone[n].shm.name.len && ngx_strncmp(oshm_zone[i].shm.name.data, shm_zone[n].shm.name.data, oshm_zone[i].shm.name.len) == 0) { goto live_shm_zone; } } ngx_shm_free(&oshm_zone[i].shm); live_shm_zone: continue; } old_shm_zone_done: /* close the unnecessary listening sockets */ ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].remain || ls[i].fd == -1) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " listening socket on %V failed", &ls[i].addr_text); } #if (NGX_HAVE_UNIX_DOMAIN) if (ls[i].sockaddr->sa_family == AF_UNIX) { u_char *name; name = ls[i].addr_text.data + sizeof("unix:") - 1; ngx_log_error(NGX_LOG_WARN, cycle->log, 0, "deleting socket %s", name); if (ngx_delete_file(name) == -1) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno, ngx_delete_file_n " %s failed", name); } } #endif } /* close the unnecessary open files */ part = &old_cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } ngx_destroy_pool(conf.temp_pool); if (ngx_process == NGX_PROCESS_MASTER || ngx_is_init_cycle(old_cycle)) { /* * perl_destruct() frees environ, if it is not the same as it was at * perl_construct() time, therefore we save the previous cycle * environment before ngx_conf_parse() where it will be changed. */ env = environ; environ = senv; ngx_destroy_pool(old_cycle->pool); cycle->old_cycle = NULL; environ = env; return cycle; } if (ngx_temp_pool == NULL) { ngx_temp_pool = ngx_create_pool(128, cycle->log); if (ngx_temp_pool == NULL) { ngx_log_error(NGX_LOG_EMERG, cycle->log, 0, "could not create ngx_temp_pool"); exit(1); } n = 10; ngx_old_cycles.elts = ngx_pcalloc(ngx_temp_pool, n * sizeof(ngx_cycle_t *)); if (ngx_old_cycles.elts == NULL) { exit(1); } ngx_old_cycles.nelts = 0; ngx_old_cycles.size = sizeof(ngx_cycle_t *); ngx_old_cycles.nalloc = n; ngx_old_cycles.pool = ngx_temp_pool; ngx_cleaner_event.handler = ngx_clean_old_cycles; ngx_cleaner_event.log = cycle->log; ngx_cleaner_event.data = &dumb; dumb.fd = (ngx_socket_t) -1; } ngx_temp_pool->log = cycle->log; old = ngx_array_push(&ngx_old_cycles); if (old == NULL) { exit(1); } *old = old_cycle; if (!ngx_cleaner_event.timer_set) { ngx_add_timer(&ngx_cleaner_event, 30000); ngx_cleaner_event.timer_set = 1; } return cycle; failed: if (!ngx_is_init_cycle(old_cycle)) { old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (old_ccf->environment) { environ = old_ccf->environment; } } /* rollback the new cycle configuration */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } if (ngx_test_config) { ngx_destroy_cycle_pools(&conf); return NULL; } ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { if (ls[i].fd == -1 || !ls[i].open) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " %V failed", &ls[i].addr_text); } } ngx_destroy_cycle_pools(&conf); return NULL; }
/*nignx程序入口*/ int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; //nignx定义的整形 ngx_log_t *log; //nginx定义的长整形 ngx_cycle_t *cycle, init_cycle; //struct ngx_cycle_s 结构 ngx_core_conf_t *ccf; // ngx_debug_init(); //只是空的定义在unix下 /*nginx错误信息初始化,涉及内存分配*/ if (ngx_strerror_init() != NGX_OK) { return 1; } /*获取nginx启动参数*/ if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } /*程序参数显示版本号和帮助信息*/ if (ngx_show_version) { ngx_write_stderr("nginx version: " NGINX_VER_BUILD NGX_LINEFEED); if (ngx_show_help) { ngx_write_stderr( "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" NGX_LINEFEED NGX_LINEFEED "Options:" NGX_LINEFEED " -?,-h : this help" NGX_LINEFEED " -v : show version and exit" NGX_LINEFEED " -V : show version and configure options then exit" NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED " -s signal : send signal to a master process: " "stop, quit, reopen, reload" NGX_LINEFEED #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" NGX_LINEFEED #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED " -g directives : set global directives out of configuration " "file" NGX_LINEFEED NGX_LINEFEED ); } /*显示编译选项*/ 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(); //获得进程ID /*初始化日志*/ 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; } /*nginx模块列表生成,make生成的*/ ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { ngx_modules[i]->index = ngx_max_module++; } cycle = ngx_init_cycle(&init_cycle); if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } if (ngx_signal) { return ngx_signal_process(cycle, ngx_signal); } ngx_os_status(cycle->log); ngx_cycle = cycle; ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ccf->master && ngx_process == NGX_PROCESS_SINGLE) { ngx_process = NGX_PROCESS_MASTER; } #if !(NGX_WIN32) if (ngx_init_signals(cycle->log) != NGX_OK) { return 1; } if (!ngx_inherited && ccf->daemon) { if (ngx_daemon(cycle->log) != NGX_OK) { return 1; } ngx_daemonized = 1; } if (ngx_inherited) { ngx_daemonized = 1; } #endif /*创建记录进程ID文件*/ 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; /* *初始化工作完成后,下面就是进程的运行模式,也是最重要的 */ if (ngx_process == NGX_PROCESS_SINGLE) { ngx_single_process_cycle(cycle); //单进程模式 } else { ngx_master_process_cycle(cycle); //多进程模式 } 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; }
int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; #if !(NGX_WIN32) struct rlimit rlmt; #endif if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } if (ngx_show_version) { ngx_log_stderr(0, "nginx version: " NGINX_VER); if (ngx_show_help) { ngx_log_stderr(0, "Usage: nginx [-?hvVt] [-s signal] [-c filename] " "[-p prefix] [-g directives]" CRLF CRLF "Options:" CRLF " -?,-h : this help" CRLF " -v : show version and exit" CRLF " -V : show version and configure options then exit" CRLF " -t : test configuration and exit" CRLF " -s signal : send signal to a master process: " "stop, quit, reopen, reload" CRLF #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" CRLF #else " -p prefix : set prefix path (default: NONE)" CRLF #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" CRLF " -g directives : set global directives out of configuration " "file" CRLF ); } if (ngx_show_configure) { #ifdef NGX_COMPILER ngx_log_stderr(0, "built by " NGX_COMPILER); #endif #if (NGX_SSL) #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME ngx_log_stderr(0, "TLS SNI support enabled"); #else ngx_log_stderr(0, "TLS SNI support disabled"); #endif #endif ngx_log_stderr(0, "configure arguments:" NGX_CONFIGURE); } if (!ngx_test_config) { return 0; } } #if (NGX_FREEBSD) ngx_debug_init(); #endif /* TODO */ ngx_max_sockets = -1; ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); #endif ngx_pid = ngx_getpid(); log = ngx_log_init(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) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); return 0; } if (ngx_signal) { return ngx_signal_process(cycle, ngx_signal); } ngx_os_status(cycle->log); ngx_cycle = cycle; ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ccf->master && ngx_process == NGX_PROCESS_SINGLE) { ngx_process = NGX_PROCESS_MASTER; } #if !(NGX_WIN32) if (geteuid() == 0) { 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_EMERG, cycle->log, ngx_errno, "setrlimit(RLIMIT_NOFILE, %i) failed", ccf->rlimit_nofile); } } if (ccf->rlimit_core != NGX_CONF_UNSET_SIZE) { 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_EMERG, cycle->log, ngx_errno, "setrlimit(RLIMIT_CORE, %i) 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_EMERG, cycle->log, ngx_errno, "setrlimit(RLIMIT_SIGPENDING, %i) failed", ccf->rlimit_sigpending); } } #endif 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); } } 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; } #endif if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } if (cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); 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; }
ngx_cycle_t * ngx_init_cycle(ngx_cycle_t *old_cycle) { void *rv; char **senv, **env; ngx_uint_t i, n; ngx_log_t *log; ngx_time_t *tp; ngx_conf_t conf; ngx_pool_t *pool; ngx_cycle_t *cycle, **old; ngx_shm_zone_t *shm_zone, *oshm_zone; ngx_list_part_t *part, *opart; ngx_open_file_t *file; ngx_listening_t *ls, *nls; ngx_core_conf_t *ccf, *old_ccf; ngx_core_module_t *module; char hostname[NGX_MAXHOSTNAMELEN]; ngx_timezone_update(); /* force localtime update with a new timezone */ tp = ngx_timeofday(); tp->sec = 0; ngx_time_update(); log = old_cycle->log; pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (pool == NULL) { return NULL; } pool->log = log; cycle = ngx_pcalloc(pool, sizeof(ngx_cycle_t)); if (cycle == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pool = pool; cycle->log = log; cycle->old_cycle = old_cycle; cycle->conf_prefix.len = old_cycle->conf_prefix.len; cycle->conf_prefix.data = ngx_pstrdup(pool, &old_cycle->conf_prefix); if (cycle->conf_prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->prefix.len = old_cycle->prefix.len; cycle->prefix.data = ngx_pstrdup(pool, &old_cycle->prefix); if (cycle->prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->conf_file.len = old_cycle->conf_file.len; cycle->conf_file.data = ngx_pnalloc(pool, old_cycle->conf_file.len + 1); if (cycle->conf_file.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_cpystrn(cycle->conf_file.data, old_cycle->conf_file.data, old_cycle->conf_file.len + 1); cycle->conf_param.len = old_cycle->conf_param.len; cycle->conf_param.data = ngx_pstrdup(pool, &old_cycle->conf_param); if (cycle->conf_param.data == NULL) { ngx_destroy_pool(pool); return NULL; } n = old_cycle->paths.nelts ? old_cycle->paths.nelts : 10; cycle->paths.elts = ngx_pcalloc(pool, n * sizeof(ngx_path_t *)); if (cycle->paths.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->paths.nelts = 0; cycle->paths.size = sizeof(ngx_path_t *); cycle->paths.nalloc = n; cycle->paths.pool = pool; if (old_cycle->open_files.part.nelts) { n = old_cycle->open_files.part.nelts; for (part = old_cycle->open_files.part.next; part; part = part->next) { n += part->nelts; } } else { n = 20; } if (ngx_list_init(&cycle->open_files, pool, n, sizeof(ngx_open_file_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } if (old_cycle->shared_memory.part.nelts) { n = old_cycle->shared_memory.part.nelts; for (part = old_cycle->shared_memory.part.next; part; part = part->next) { n += part->nelts; } } else { n = 1; } if (ngx_list_init(&cycle->shared_memory, pool, n, sizeof(ngx_shm_zone_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } n = old_cycle->listening.nelts ? old_cycle->listening.nelts : 10; cycle->listening.elts = ngx_pcalloc(pool, n * sizeof(ngx_listening_t)); if (cycle->listening.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->listening.nelts = 0; cycle->listening.size = sizeof(ngx_listening_t); cycle->listening.nalloc = n; cycle->listening.pool = pool; ngx_queue_init(&cycle->reusable_connections_queue); cycle->conf_ctx = ngx_pcalloc(pool, ngx_max_module * sizeof(void *)); if (cycle->conf_ctx == NULL) { ngx_destroy_pool(pool); return NULL; } if (gethostname(hostname, NGX_MAXHOSTNAMELEN) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "gethostname() failed"); ngx_destroy_pool(pool); return NULL; } /* on Linux gethostname() silently truncates name that does not fit */ hostname[NGX_MAXHOSTNAMELEN - 1] = '\0'; cycle->hostname.len = ngx_strlen(hostname); cycle->hostname.data = ngx_pnalloc(pool, cycle->hostname.len); if (cycle->hostname.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_strlow(cycle->hostname.data, (u_char *) hostname, cycle->hostname.len); for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } module = ngx_modules[i]->ctx; if (module->create_conf) { rv = module->create_conf(cycle); if (rv == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->conf_ctx[ngx_modules[i]->index] = rv; } } senv = environ; ngx_memzero(&conf, sizeof(ngx_conf_t)); /* STUB: init array ? */ conf.args = ngx_array_create(pool, 10, sizeof(ngx_str_t)); if (conf.args == NULL) { ngx_destroy_pool(pool); return NULL; } conf.temp_pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (conf.temp_pool == NULL) { ngx_destroy_pool(pool); return NULL; } conf.ctx = cycle->conf_ctx; conf.cycle = cycle; conf.pool = pool; conf.log = log; conf.module_type = NGX_CORE_MODULE; conf.cmd_type = NGX_MAIN_CONF; #if 0 log->log_level = NGX_LOG_DEBUG_ALL; #endif if (ngx_conf_param(&conf) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_conf_parse(&conf, &cycle->conf_file) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_test_config && !ngx_quiet_mode) { ngx_log_stderr(0, "the configuration file %s syntax is ok", cycle->conf_file.data); } for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } module = ngx_modules[i]->ctx; if (module->init_conf) { if (module->init_conf(cycle, cycle->conf_ctx[ngx_modules[i]->index]) == NGX_CONF_ERROR) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } } } if (ngx_process == NGX_PROCESS_SIGNALLER) { return cycle; } ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ngx_test_config) { if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } } else if (!ngx_is_init_cycle(old_cycle)) { /* * we do not create the pid file in the first ngx_init_cycle() call * because we need to write the demonized process pid */ old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (ccf->pid.len != old_ccf->pid.len || ngx_strcmp(ccf->pid.data, old_ccf->pid.data) != 0) { /* new pid file name */ if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } ngx_delete_pidfile(old_cycle); } } if (ngx_test_lockfile(cycle->lock_file.data, log) != NGX_OK) { goto failed; } if (ngx_create_paths(cycle, ccf->user) != NGX_OK) { goto failed; } if (ngx_log_open_default(cycle) != NGX_OK) { goto failed; } /* open the new files */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].name.len == 0) { continue; } file[i].fd = ngx_open_file(file[i].name.data, NGX_FILE_APPEND, NGX_FILE_CREATE_OR_OPEN, NGX_FILE_DEFAULT_ACCESS); ngx_log_debug3(NGX_LOG_DEBUG_CORE, log, 0, "log: %p %d \"%s\"", &file[i], file[i].fd, file[i].name.data); if (file[i].fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_open_file_n " \"%s\" failed", file[i].name.data); goto failed; } #if !(NGX_WIN32) if (fcntl(file[i].fd, F_SETFD, FD_CLOEXEC) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "fcntl(FD_CLOEXEC) \"%s\" failed", file[i].name.data); goto failed; } #endif } cycle->log = &cycle->new_log; pool->log = &cycle->new_log; /* create shared memory */ part = &cycle->shared_memory.part; shm_zone = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; i = 0; } if (shm_zone[i].shm.size == 0) { ngx_log_error(NGX_LOG_EMERG, log, 0, "zero size shared memory zone \"%V\"", &shm_zone[i].shm.name); goto failed; } shm_zone[i].shm.log = cycle->log; opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (n = 0; /* void */ ; n++) { if (n >= opart->nelts) { if (opart->next == NULL) { break; } opart = opart->next; oshm_zone = opart->elts; n = 0; } if (shm_zone[i].shm.name.len != oshm_zone[n].shm.name.len) { continue; } if (ngx_strncmp(shm_zone[i].shm.name.data, oshm_zone[n].shm.name.data, shm_zone[i].shm.name.len) != 0) { continue; } if (shm_zone[i].tag == oshm_zone[n].tag && shm_zone[i].shm.size == oshm_zone[n].shm.size) { shm_zone[i].shm.addr = oshm_zone[n].shm.addr; if (shm_zone[i].init(&shm_zone[i], oshm_zone[n].data) != NGX_OK) { goto failed; } goto shm_zone_found; } ngx_shm_free(&oshm_zone[n].shm); break; } if (ngx_shm_alloc(&shm_zone[i].shm) != NGX_OK) { goto failed; } if (ngx_init_zone_pool(cycle, &shm_zone[i]) != NGX_OK) { goto failed; } if (shm_zone[i].init(&shm_zone[i], NULL) != NGX_OK) { goto failed; } shm_zone_found: continue; } /* handle the listening sockets */ if (old_cycle->listening.nelts) { ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { ls[i].remain = 0; } nls = cycle->listening.elts; for (n = 0; n < cycle->listening.nelts; n++) { for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].ignore) { continue; } if (ngx_cmp_sockaddr(nls[n].sockaddr, ls[i].sockaddr) == NGX_OK) { nls[n].fd = ls[i].fd; nls[n].previous = &ls[i]; ls[i].remain = 1; if (ls[n].backlog != nls[i].backlog) { nls[n].listen = 1; } #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) /* * FreeBSD, except the most recent versions, * could not remove accept filter */ nls[n].deferred_accept = ls[i].deferred_accept; if (ls[i].accept_filter && nls[n].accept_filter) { if (ngx_strcmp(ls[i].accept_filter, nls[n].accept_filter) != 0) { nls[n].delete_deferred = 1; nls[n].add_deferred = 1; } } else if (ls[i].accept_filter) { nls[n].delete_deferred = 1; } else if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[n].deferred_accept && !nls[n].deferred_accept) { nls[n].delete_deferred = 1; } else if (ls[i].deferred_accept != nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif break; } } if (nls[n].fd == (ngx_socket_t) -1) { nls[n].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif } } } else { ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { ls[i].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (ls[i].accept_filter) { ls[i].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept) { ls[i].add_deferred = 1; } #endif } } if (ngx_open_listening_sockets(cycle) != NGX_OK) { goto failed; } if (!ngx_test_config) { ngx_configure_listening_sockets(cycle); } /* commit the new cycle configuration */ if (!ngx_use_stderr) { (void) ngx_log_redirect_stderr(cycle); } pool->log = cycle->log; for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->init_module) { if (ngx_modules[i]->init_module(cycle) != NGX_OK) { /* fatal */ exit(1); } } } /* close and delete stuff that lefts from an old cycle */ /* free the unnecessary shared memory */ opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (i = 0; /* void */ ; i++) { if (i >= opart->nelts) { if (opart->next == NULL) { goto old_shm_zone_done; } opart = opart->next; oshm_zone = opart->elts; i = 0; } part = &cycle->shared_memory.part; shm_zone = part->elts; for (n = 0; /* void */ ; n++) { if (n >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; n = 0; } if (oshm_zone[i].shm.name.len == shm_zone[n].shm.name.len && ngx_strncmp(oshm_zone[i].shm.name.data, shm_zone[n].shm.name.data, oshm_zone[i].shm.name.len) == 0) { goto live_shm_zone; } } ngx_shm_free(&oshm_zone[i].shm); live_shm_zone: continue; } old_shm_zone_done: /* close the unnecessary listening sockets */ ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].remain || ls[i].fd == (ngx_socket_t) -1) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " listening socket on %V failed", &ls[i].addr_text); } #if (NGX_HAVE_UNIX_DOMAIN) if (ls[i].sockaddr->sa_family == AF_UNIX) { u_char *name; name = ls[i].addr_text.data + sizeof("unix:") - 1; ngx_log_error(NGX_LOG_WARN, cycle->log, 0, "deleting socket %s", name); if (ngx_delete_file(name) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno, ngx_delete_file_n " %s failed", name); } } #endif } /* close the unnecessary open files */ part = &old_cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } ngx_destroy_pool(conf.temp_pool); if (ngx_process == NGX_PROCESS_MASTER || ngx_is_init_cycle(old_cycle)) { /* * perl_destruct() frees environ, if it is not the same as it was at * perl_construct() time, therefore we save the previous cycle * environment before ngx_conf_parse() where it will be changed. */ env = environ; environ = senv; ngx_destroy_pool(old_cycle->pool); cycle->old_cycle = NULL; environ = env; return cycle; } if (ngx_temp_pool == NULL) { ngx_temp_pool = ngx_create_pool(128, cycle->log); if (ngx_temp_pool == NULL) { ngx_log_error(NGX_LOG_EMERG, cycle->log, 0, "could not create ngx_temp_pool"); exit(1); } n = 10; ngx_old_cycles.elts = ngx_pcalloc(ngx_temp_pool, n * sizeof(ngx_cycle_t *)); if (ngx_old_cycles.elts == NULL) { exit(1); } ngx_old_cycles.nelts = 0; ngx_old_cycles.size = sizeof(ngx_cycle_t *); ngx_old_cycles.nalloc = n; ngx_old_cycles.pool = ngx_temp_pool; ngx_cleaner_event.handler = ngx_clean_old_cycles; ngx_cleaner_event.log = cycle->log; ngx_cleaner_event.data = &dumb; dumb.fd = (ngx_socket_t) -1; } ngx_temp_pool->log = cycle->log; old = ngx_array_push(&ngx_old_cycles); if (old == NULL) { exit(1); } *old = old_cycle; if (!ngx_cleaner_event.timer_set) { ngx_add_timer(&ngx_cleaner_event, 30000); ngx_cleaner_event.timer_set = 1; } return cycle; failed: if (!ngx_is_init_cycle(old_cycle)) { old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (old_ccf->environment) { environ = old_ccf->environment; } } /* rollback the new cycle configuration */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } if (ngx_test_config) { ngx_destroy_cycle_pools(&conf); return NULL; } ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { if (ls[i].fd == (ngx_socket_t) -1 || !ls[i].open) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " %V failed", &ls[i].addr_text); } } ngx_destroy_cycle_pools(&conf); return NULL; }
/* 加载配置文件,并回调create_conf,init_conf, init_module等; 初始化各个配置,并打开监听端口,设置优化选项; */ ngx_cycle_t * ngx_init_cycle(ngx_cycle_t *old_cycle) {//整个程序的主要初始化,配置加载,解析,各个模块的初始化回调函数,指令的set回调函数调用,监听端口打开,共享内存申请等等都在这里. void *rv; char **senv, **env; ngx_uint_t i, n; ngx_log_t *log; ngx_time_t *tp; ngx_conf_t conf; ngx_pool_t *pool; ngx_cycle_t *cycle, **old; ngx_shm_zone_t *shm_zone, *oshm_zone; ngx_list_part_t *part, *opart; ngx_open_file_t *file; ngx_listening_t *ls, *nls; ngx_core_conf_t *ccf, *old_ccf; ngx_core_module_t *module; char hostname[NGX_MAXHOSTNAMELEN]; ngx_timezone_update(); /* force localtime update with a new timezone */ tp = ngx_timeofday();//k : ngx_cached_time tp->sec = 0;//秒设置为0 ngx_time_update();//迫使当前的缓存时间更新。 log = old_cycle->log; pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (pool == NULL) { return NULL; } pool->log = log; cycle = ngx_pcalloc(pool, sizeof(ngx_cycle_t));//下一个过程吗 if (cycle == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pool = pool;//cycle也是包含在pool里面的! ,也就是,释放了cycle->pool后,cycle也释放了 cycle->log = log; cycle->new_log.log_level = NGX_LOG_ERR; cycle->old_cycle = old_cycle; //下面拷贝一下旧的配置路径什么的,参数等到新的cycle cycle->conf_prefix.len = old_cycle->conf_prefix.len; cycle->conf_prefix.data = ngx_pstrdup(pool, &old_cycle->conf_prefix); if (cycle->conf_prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->prefix.len = old_cycle->prefix.len; cycle->prefix.data = ngx_pstrdup(pool, &old_cycle->prefix); if (cycle->prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->conf_file.len = old_cycle->conf_file.len; cycle->conf_file.data = ngx_pnalloc(pool, old_cycle->conf_file.len + 1); if (cycle->conf_file.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_cpystrn(cycle->conf_file.data, old_cycle->conf_file.data, old_cycle->conf_file.len + 1); cycle->conf_param.len = old_cycle->conf_param.len; cycle->conf_param.data = ngx_pstrdup(pool, &old_cycle->conf_param); if (cycle->conf_param.data == NULL) { ngx_destroy_pool(pool); return NULL; } //干嘛的? n = old_cycle->pathes.nelts ? old_cycle->pathes.nelts : 10; cycle->pathes.elts = ngx_pcalloc(pool, n * sizeof(ngx_path_t *)); if (cycle->pathes.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pathes.nelts = 0; cycle->pathes.size = sizeof(ngx_path_t *); cycle->pathes.nalloc = n; cycle->pathes.pool = pool; if (old_cycle->open_files.part.nelts) { n = old_cycle->open_files.part.nelts; for (part = old_cycle->open_files.part.next; part; part = part->next) { n += part->nelts; } } else { n = 20; } if (ngx_list_init(&cycle->open_files, pool, n, sizeof(ngx_open_file_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } //拷贝共享内存 if (old_cycle->shared_memory.part.nelts) { n = old_cycle->shared_memory.part.nelts; for (part = old_cycle->shared_memory.part.next; part; part = part->next) { n += part->nelts; } } else { n = 1; } if (ngx_list_init(&cycle->shared_memory, pool, n, sizeof(ngx_shm_zone_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } //拷贝一下监听端口的信息; n = old_cycle->listening.nelts ? old_cycle->listening.nelts : 10; cycle->listening.elts = ngx_pcalloc(pool, n * sizeof(ngx_listening_t)); if (cycle->listening.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->listening.nelts = 0; cycle->listening.size = sizeof(ngx_listening_t); cycle->listening.nalloc = n; cycle->listening.pool = pool; //为每个模块分配一个配置上下文指针,用来保存每个模块设置的配置数据 cycle->conf_ctx = ngx_pcalloc(pool, ngx_max_module * sizeof(void *)); if (cycle->conf_ctx == NULL) { ngx_destroy_pool(pool); return NULL; } if (gethostname(hostname, NGX_MAXHOSTNAMELEN) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "gethostname() failed"); ngx_destroy_pool(pool); return NULL; } /* on Linux gethostname() silently truncates name that does not fit */ hostname[NGX_MAXHOSTNAMELEN - 1] = '\0'; cycle->hostname.len = ngx_strlen(hostname); cycle->hostname.data = ngx_pnalloc(pool, cycle->hostname.len); if (cycle->hostname.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_strlow(cycle->hostname.data, (u_char *) hostname, cycle->hostname.len); //k:for core modules. for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } //对于核心模块 module = ngx_modules[i]->ctx; if (module->create_conf) {//如果核心模块设置了create_conf回调,则调用它们 rv = module->create_conf(cycle); if (rv == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->conf_ctx[ ngx_modules[i]->index ] = rv;//帮模块们保存create_conf返回的数据。后续可以方便取到 } } senv = environ;//保留老的environ,这个环境变量已经被我们拷贝到了新地址的 ngx_memzero(&conf, sizeof(ngx_conf_t)); /* STUB: init array ? */ conf.args = ngx_array_create(pool, 10, sizeof(ngx_str_t)); if (conf.args == NULL) { ngx_destroy_pool(pool); return NULL; } conf.temp_pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (conf.temp_pool == NULL) { ngx_destroy_pool(pool); return NULL; } //切换到新的配置 conf.ctx = cycle->conf_ctx; conf.cycle = cycle; conf.pool = pool; conf.log = log; conf.module_type = NGX_CORE_MODULE; conf.cmd_type = NGX_MAIN_CONF; #if 0 log->log_level = NGX_LOG_DEBUG_ALL; #endif if (ngx_conf_param(&conf) != NGX_CONF_OK) {//调用ngx_conf_parse解析全局指令,貌似是做参数准备的。 environ = senv;//还原老的environ,因为perl会改变它 ngx_destroy_cycle_pools(&conf); return NULL; } //解析配置文件,调用各个配置文件的set函数等。 if (ngx_conf_parse(&conf, &cycle->conf_file) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_test_config && !ngx_quiet_mode) {//这就是经典的那个-t参数啦 ngx_log_stderr(0, "the configuration file %s syntax is ok", cycle->conf_file.data); } for (i = 0; ngx_modules[i]; i++) { //刚才各个配置指令已经调用了其set函数的。下面调用一下每个模块的init_conf,也就是每个模块的各个指令已经设置,现在开始模块本身了。 if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } //对于NGX_CORE_MODULE,调用它他们的init_conf回调 module = ngx_modules[i]->ctx;//得到模块初始化设置的数据,然后调用其init_conf if (module->init_conf) { if (module->init_conf(cycle, cycle->conf_ctx[ngx_modules[i]->index])== NGX_CONF_ERROR){ //第二个参数是在create_conf回调返回的东西 environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } } } if (ngx_process == NGX_PROCESS_SIGNALLER) { return cycle;//如果是加-s reload等启动的,这里可以返回了。服务需要重启啥的,不是全新启动。在这里设置的ngx_get_options } // 最核心的配置 ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);//k conf_ctx[module.index] if (ngx_test_config) { if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } } else if (!ngx_is_init_cycle(old_cycle)) {//第一次调用,old_cycle的配置相关的为空,第二次才是非空的。也就是下面的注释介绍的 /* * we do not create the pid file in the first ngx_init_cycle() call * because we need to write the demonized process pid */ old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (ccf->pid.len != old_ccf->pid.len || ngx_strcmp(ccf->pid.data, old_ccf->pid.data) != 0) { /* new pid file name */ if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } ngx_delete_pidfile(old_cycle);//删除旧的,这是啥原因,比如配置重新加载吗,文件变了啥的 } } //就打开文件,关闭,然后删除之 if (ngx_test_lockfile(cycle->lock_file.data, log) != NGX_OK) { goto failed; } //创建这些目录,并设置权限啥的 if (ngx_create_pathes(cycle, ccf->user) != NGX_OK) { goto failed; } if (cycle->new_log.file == NULL) {//找到"logs/error.log"的ngx_open_file_t*结构,不open打开 cycle->new_log.file = ngx_conf_open_file(cycle, &error_log);//"logs/error.log" if (cycle->new_log.file == NULL) { goto failed; } } /* open the new files */ part = &cycle->open_files.part; file = part->elts; //一个个打开这些文件,APPEND模式打开 for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].name.len == 0) { continue; } //真正打开这些文件,append模式 file[i].fd = ngx_open_file(file[i].name.data, NGX_FILE_APPEND, NGX_FILE_CREATE_OR_OPEN, NGX_FILE_DEFAULT_ACCESS); ngx_log_debug3(NGX_LOG_DEBUG_CORE, log, 0, "log: %p %d \"%s\"", &file[i], file[i].fd, file[i].name.data); if (file[i].fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_open_file_n " \"%s\" failed", file[i].name.data); goto failed; } #if !(NGX_WIN32) // 这里设置为FD_CLOEXEC表示当程序执行exec函数时本fd将被系统自动关闭,表示不传递给exec创建的新进程。close-on-exec if (fcntl(file[i].fd, F_SETFD, FD_CLOEXEC) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "fcntl(FD_CLOEXEC) \"%s\" failed", file[i].name.data); goto failed; } #endif } cycle->log = &cycle->new_log; pool->log = &cycle->new_log; /* create shared memory */ part = &cycle->shared_memory.part; shm_zone = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; i = 0; } if (shm_zone[i].shm.size == 0) { ngx_log_error(NGX_LOG_EMERG, log, 0, "zero size shared memory zone \"%V\"", &shm_zone[i].shm.name); goto failed; } if (shm_zone[i].init == NULL) { /* unused shared zone */ continue; } shm_zone[i].shm.log = cycle->log; opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (n = 0; /* void */ ; n++) { if (n >= opart->nelts) { if (opart->next == NULL) { break; } opart = opart->next; oshm_zone = opart->elts; n = 0; } if (shm_zone[i].shm.name.len != oshm_zone[n].shm.name.len) { continue; } if (ngx_strncmp(shm_zone[i].shm.name.data, oshm_zone[n].shm.name.data, shm_zone[i].shm.name.len) != 0) { continue; } if (shm_zone[i].shm.size == oshm_zone[n].shm.size) { shm_zone[i].shm.addr = oshm_zone[n].shm.addr; if (shm_zone[i].init(&shm_zone[i], oshm_zone[n].data) != NGX_OK) { goto failed; } goto shm_zone_found; } ngx_shm_free(&oshm_zone[n].shm); break; } if (ngx_shm_alloc(&shm_zone[i].shm) != NGX_OK) { goto failed; } if (ngx_init_zone_pool(cycle, &shm_zone[i]) != NGX_OK) { goto failed; } if (shm_zone[i].init(&shm_zone[i], NULL) != NGX_OK) { goto failed; } shm_zone_found: continue; } /* handle the listening sockets */ if (old_cycle->listening.nelts) {//如果设置了继承SOCK,就拷贝到cycle来 ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { ls[i].remain = 0;//标记为全都不需要了,后面会清除 } nls = cycle->listening.elts; for (n = 0; n < cycle->listening.nelts; n++) { for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].ignore) { continue; } if (ngx_cmp_sockaddr(nls[n].sockaddr, ls[i].sockaddr) == NGX_OK) {//如果地址完全相同,那后面就不需要关闭,直接拷贝fd就行了 nls[n].fd = ls[i].fd; nls[n].previous = &ls[i]; ls[i].remain = 1; if (ls[n].backlog != nls[i].backlog) { nls[n].listen = 1; } #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) /* * FreeBSD, except the most recent versions, * could not remove accept filter */ nls[n].deferred_accept = ls[i].deferred_accept; if (ls[i].accept_filter && nls[n].accept_filter) { if (ngx_strcmp(ls[i].accept_filter, nls[n].accept_filter) != 0) { nls[n].delete_deferred = 1; nls[n].add_deferred = 1; } } else if (ls[i].accept_filter) { nls[n].delete_deferred = 1; } else if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[n].deferred_accept && !nls[n].deferred_accept) { nls[n].delete_deferred = 1; } else if (ls[i].deferred_accept != nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif break; } } if (nls[n].fd == -1) { nls[n].open = 1; } } } else { ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { ls[i].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (ls[i].accept_filter) { ls[i].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept) { ls[i].add_deferred = 1; } #endif } } //下面一个个打开cycle->listening的listen的端口,并设置为listening端口 //这些监听端口的可读事件是在ngx_event_core_module模块中设置的,其进程初始化函数为ngx_event_process_init里面会放入epoll里面 if (ngx_open_listening_sockets(cycle) != NGX_OK) { goto failed; } if (!ngx_test_config) {//如果不是测试配置,设置一下各个优化选项,比如发送,接收缓冲区大小,TCP_DEFER_ACCEPT等 ngx_configure_listening_sockets(cycle); } /* commit the new cycle configuration */ if (!ngx_use_stderr && cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); } } pool->log = cycle->log; for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->init_module) {//对所有模块,调用其init_module回调 if (ngx_modules[i]->init_module(cycle) != NGX_OK) { /* fatal */ exit(1); } } } /* close and delete stuff that lefts from an old cycle */ /* free the unnecessary shared memory */ opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (i = 0; /* void */ ; i++) { if (i >= opart->nelts) { if (opart->next == NULL) { goto old_shm_zone_done; } opart = opart->next; oshm_zone = opart->elts; i = 0; } part = &cycle->shared_memory.part; shm_zone = part->elts; for (n = 0; /* void */ ; n++) { if (n >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; n = 0; } if (oshm_zone[i].shm.name.len == shm_zone[n].shm.name.len && ngx_strncmp(oshm_zone[i].shm.name.data, shm_zone[n].shm.name.data, oshm_zone[i].shm.name.len) == 0){ goto live_shm_zone; } } ngx_shm_free(&oshm_zone[i].shm); live_shm_zone: continue; } old_shm_zone_done: /* close the unnecessary listening sockets */ ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].remain || ls[i].fd == -1) { continue;//需要保留或者fd无效,不用删除,因为已经拷贝到cycle中了 } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,ngx_close_socket_n " listening socket on %V failed", &ls[i].addr_text); } #if (NGX_HAVE_UNIX_DOMAIN) if (ls[i].sockaddr->sa_family == AF_UNIX) { u_char *name; name = ls[i].addr_text.data + sizeof("unix:") - 1; ngx_log_error(NGX_LOG_WARN, cycle->log, 0, "deleting socket %s", name); if (ngx_delete_file(name) == -1) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno, ngx_delete_file_n " %s failed", name); } } #endif } /* close the unnecessary open files */ part = &old_cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } ngx_destroy_pool(conf.temp_pool); if (ngx_process == NGX_PROCESS_MASTER || ngx_is_init_cycle(old_cycle)) {//ngx_is_init_cycle第一次调用false //这是怎么进来的? /* * perl_destruct() frees environ, if it is not the same as it was at * perl_construct() time, therefore we save the previous cycle * environment before ngx_conf_parse() where it will be changed. */ env = environ; environ = senv;//还原之前保存的环境变量地址 ngx_destroy_pool(old_cycle->pool); cycle->old_cycle = NULL; environ = env; return cycle; } if (ngx_temp_pool == NULL) { ngx_temp_pool = ngx_create_pool(128, cycle->log); if (ngx_temp_pool == NULL) { ngx_log_error(NGX_LOG_EMERG, cycle->log, 0, "can not create ngx_temp_pool"); exit(1); } n = 10; ngx_old_cycles.elts = ngx_pcalloc(ngx_temp_pool, n * sizeof(ngx_cycle_t *)); if (ngx_old_cycles.elts == NULL) { exit(1); } ngx_old_cycles.nelts = 0; ngx_old_cycles.size = sizeof(ngx_cycle_t *); ngx_old_cycles.nalloc = n; ngx_old_cycles.pool = ngx_temp_pool; ngx_cleaner_event.handler = ngx_clean_old_cycles; ngx_cleaner_event.log = cycle->log; ngx_cleaner_event.data = &dumb; dumb.fd = (ngx_socket_t) -1; } ngx_temp_pool->log = cycle->log; old = ngx_array_push(&ngx_old_cycles); if (old == NULL) { exit(1); } *old = old_cycle; if (!ngx_cleaner_event.timer_set) {//如果还没有设置定时器,设置定时器,30秒后清除老的cycle? ngx_add_timer(&ngx_cleaner_event, 30000); ngx_cleaner_event.timer_set = 1;//标记此处已经设置过定时器了。 } return cycle; failed: if (!ngx_is_init_cycle(old_cycle)) { old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (old_ccf->environment) { environ = old_ccf->environment; } } /* rollback the new cycle configuration */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } if (ngx_test_config) { ngx_destroy_cycle_pools(&conf); return NULL; } ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { if (ls[i].fd == -1 || !ls[i].open) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " %V failed", &ls[i].addr_text); } } ngx_destroy_cycle_pools(&conf); return NULL; }
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; zlog_init_conf_path(); if (zlog_load_conf(zlog_init)) { return 1; } 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; struct sigaction act; memset(&act, 0, sizeof(struct sigaction)); sigemptyset(&act.sa_mask); act.sa_sigaction = sig_user1_handler; act.sa_flags = SA_SIGINFO; if(-1 == sigaction(SIGUSR1, &act, NULL)) { return 1; } if (ngx_process == NGX_PROCESS_SINGLE) { ngx_single_process_cycle(cycle); } else { if (NGX_OK != ngx_before_master_cycle(cycle)) { return 1; } ngx_master_process_cycle(cycle); } return 0; }
/*初始化全局唯一的ngx_cycle_t*/ ngx_cycle_t * ngx_init_cycle(ngx_cycle_t *old_cycle) { void *rv; char **senv, **env; ngx_uint_t i, n; ngx_log_t *log; ngx_time_t *tp; ngx_conf_t conf; ngx_pool_t *pool; ngx_cycle_t *cycle, **old; ngx_shm_zone_t *shm_zone, *oshm_zone; ngx_list_part_t *part, *opart; ngx_open_file_t *file; ngx_listening_t *ls, *nls; ngx_core_conf_t *ccf, *old_ccf; ngx_core_module_t *module; char hostname[NGX_MAXHOSTNAMELEN]; ngx_timezone_update(); /* force localtime update with a new timezone */ /*获取缓存的当前时间*/ tp = ngx_timeofday(); tp->sec = 0; /*更新时间*/ ngx_time_update(); log = old_cycle->log; /*创建内存池*/ pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (pool == NULL) { return NULL; } pool->log = log; /*申请cycle*/ cycle = ngx_pcalloc(pool, sizeof(ngx_cycle_t)); if (cycle == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pool = pool; cycle->log = log; cycle->old_cycle = old_cycle; /*转存conf_prefix*/ cycle->conf_prefix.len = old_cycle->conf_prefix.len; cycle->conf_prefix.data = ngx_pstrdup(pool, &old_cycle->conf_prefix); if (cycle->conf_prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } /*转存prefix*/ cycle->prefix.len = old_cycle->prefix.len; cycle->prefix.data = ngx_pstrdup(pool, &old_cycle->prefix); if (cycle->prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } /*转存conf_file*/ cycle->conf_file.len = old_cycle->conf_file.len; cycle->conf_file.data = ngx_pnalloc(pool, old_cycle->conf_file.len + 1); if (cycle->conf_file.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_cpystrn(cycle->conf_file.data, old_cycle->conf_file.data, old_cycle->conf_file.len + 1); /*转存conf_param*/ cycle->conf_param.len = old_cycle->conf_param.len; cycle->conf_param.data = ngx_pstrdup(pool, &old_cycle->conf_param); if (cycle->conf_param.data == NULL) { ngx_destroy_pool(pool); return NULL; } /*初始化paths动态数组,其中保存的是nginx所要操作的目录*/ n = old_cycle->paths.nelts ? old_cycle->paths.nelts : 10; cycle->paths.elts = ngx_pcalloc(pool, n * sizeof(ngx_path_t *)); if (cycle->paths.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->paths.nelts = 0; cycle->paths.size = sizeof(ngx_path_t *); cycle->paths.nalloc = n; cycle->paths.pool = pool; /*初始化cycle->config_dump动态数组*/ if (ngx_array_init(&cycle->config_dump, pool, 1, sizeof(ngx_conf_dump_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } if (old_cycle->open_files.part.nelts) { n = old_cycle->open_files.part.nelts; for (part = old_cycle->open_files.part.next; part; part = part->next) { n += part->nelts; } } else { n = 20; } /*初始化cycle->open_files链表*/ if (ngx_list_init(&cycle->open_files, pool, n, sizeof(ngx_open_file_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } if (old_cycle->shared_memory.part.nelts) { n = old_cycle->shared_memory.part.nelts; for (part = old_cycle->shared_memory.part.next; part; part = part->next) { n += part->nelts; } } else { n = 1; } /*初始化cycle->shared_memory共享内存*/ if (ngx_list_init(&cycle->shared_memory, pool, n, sizeof(ngx_shm_zone_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } /*初始化cycle->listening动态数组*/ n = old_cycle->listening.nelts ? old_cycle->listening.nelts : 10; cycle->listening.elts = ngx_pcalloc(pool, n * sizeof(ngx_listening_t)); if (cycle->listening.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->listening.nelts = 0; cycle->listening.size = sizeof(ngx_listening_t); cycle->listening.nalloc = n; cycle->listening.pool = pool; ngx_queue_init(&cycle->reusable_connections_queue); /*初始化存储所有模块配置项结构体的指针*/ cycle->conf_ctx = ngx_pcalloc(pool, ngx_max_module * sizeof(void *)); if (cycle->conf_ctx == NULL) { ngx_destroy_pool(pool); return NULL; } /*获取主机名,并初始化cycle->hostname*/ if (gethostname(hostname, NGX_MAXHOSTNAMELEN) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "gethostname() failed"); ngx_destroy_pool(pool); return NULL; } /* on Linux gethostname() silently truncates name that does not fit */ hostname[NGX_MAXHOSTNAMELEN - 1] = '\0'; cycle->hostname.len = ngx_strlen(hostname); cycle->hostname.data = ngx_pnalloc(pool, cycle->hostname.len); if (cycle->hostname.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_strlow(cycle->hostname.data, (u_char *) hostname, cycle->hostname.len); /*初始化cycle->modules cycle->modules_n*/ if (ngx_cycle_modules(cycle) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } /*处理所有的NGX_CORE_MODULE,调用所有核心模块的create_conf函数创建存储配置项的结构体*/ for (i = 0; cycle->modules[i]; i++) { if (cycle->modules[i]->type != NGX_CORE_MODULE) { continue; } /*获取模块上下文*/ module = cycle->modules[i]->ctx; if (module->create_conf) { rv = module->create_conf(cycle); if (rv == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->conf_ctx[cycle->modules[i]->index] = rv; //将创建的存储配置项的结构体挂在cycle->conf_ctx中 } } /*暂存环境变量*/ senv = environ; ngx_memzero(&conf, sizeof(ngx_conf_t)); /* STUB: init array ? */ conf.args = ngx_array_create(pool, 10, sizeof(ngx_str_t)); if (conf.args == NULL) { ngx_destroy_pool(pool); return NULL; } conf.temp_pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (conf.temp_pool == NULL) { ngx_destroy_pool(pool); return NULL; } /*conf.ctx指向的是cycle->conf_ctx*/ conf.ctx = cycle->conf_ctx; conf.cycle = cycle; conf.pool = pool; conf.log = log; conf.module_type = NGX_CORE_MODULE; conf.cmd_type = NGX_MAIN_CONF; #if 0 log->log_level = NGX_LOG_DEBUG_ALL; #endif /*解析-g携带的参数中需要特殊处理的配置项及其参数值*/ if (ngx_conf_param(&conf) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } /*针对所有核心模块解析nginx.conf配置文件*/ if (ngx_conf_parse(&conf, &cycle->conf_file) != NGX_CONF_OK) { environ = senv; //恢复环境 ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_test_config && !ngx_quiet_mode) { ngx_log_stderr(0, "the configuration file %s syntax is ok", cycle->conf_file.data); } /*调用所有核心模块的init_conf方法*/ for (i = 0; cycle->modules[i]; i++) { if (cycle->modules[i]->type != NGX_CORE_MODULE) { continue; } module = cycle->modules[i]->ctx; if (module->init_conf) { if (module->init_conf(cycle, cycle->conf_ctx[cycle->modules[i]->index]) == NGX_CONF_ERROR) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } } } /*单进程模式,返回*/ if (ngx_process == NGX_PROCESS_SIGNALLER) { return cycle; } /*获取核心模块的存储配置项结构体的指针*/ ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ngx_test_config) { if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } } else if (!ngx_is_init_cycle(old_cycle)) { //cycle->conf_ctx != NULL /* * we do not create the pid file in the first ngx_init_cycle() call * because we need to write the demonized process pid */ /*获取临时的核心模块存储配置项的结构体指针*/ old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); /*创建pidfile*/ if (ccf->pid.len != old_ccf->pid.len || ngx_strcmp(ccf->pid.data, old_ccf->pid.data) != 0) { /* new pid file name */ /*创建新的pidfile并写入当前进程id*/ if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } /*删除老的pidfile*/ ngx_delete_pidfile(old_cycle); } } if (ngx_test_lockfile(cycle->lock_file.data, log) != NGX_OK) { goto failed; } /*创建在配置文件中出现的文件目录*/ if (ngx_create_paths(cycle, ccf->user) != NGX_OK) { goto failed; } /*打开日志文件*/ if (ngx_log_open_default(cycle) != NGX_OK) { goto failed; } /* open the new files */ /*打开open_files动态数组中的没有打开的文件*/ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].name.len == 0) { continue; } /* * 在打开文件时候带有O_APPEND选项,则当有多个进程往这个文件写入内容的时候, * 每个操作都是原子性的,这样就保证了内容的正确性。举个例子,多个worker进程 * 可能存在同时往一个日志文件中写入内容的情况,这个时候每个write都是原子性的。 */ file[i].fd = ngx_open_file(file[i].name.data, NGX_FILE_APPEND, NGX_FILE_CREATE_OR_OPEN, NGX_FILE_DEFAULT_ACCESS); ngx_log_debug3(NGX_LOG_DEBUG_CORE, log, 0, "log: %p %d \"%s\"", &file[i], file[i].fd, file[i].name.data); if (file[i].fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_open_file_n " \"%s\" failed", file[i].name.data); goto failed; } #if !(NGX_WIN32) if (fcntl(file[i].fd, F_SETFD, FD_CLOEXEC) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "fcntl(FD_CLOEXEC) \"%s\" failed", file[i].name.data); goto failed; } #endif } /*log也指向了日志文件,不再打屏*/ cycle->log = &cycle->new_log; pool->log = &cycle->new_log; /* create shared memory */ /*创建共享内存*/ /* * 当模块调用ngx_shared_memory_add函数的时候并没有申请空间,只是说该模块需要使用共享内存,并挂在cycle->shared_memoery * 然后在这个地方才开始真正进行初始化申请共享内存 */ part = &cycle->shared_memory.part; shm_zone = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; i = 0; } if (shm_zone[i].shm.size == 0) { ngx_log_error(NGX_LOG_EMERG, log, 0, "zero size shared memory zone \"%V\"", &shm_zone[i].shm.name); goto failed; } shm_zone[i].shm.log = cycle->log; /*下面涉及到共享内存的复用*/ opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (n = 0; /* void */ ; n++) { if (n >= opart->nelts) { if (opart->next == NULL) { break; } opart = opart->next; oshm_zone = opart->elts; n = 0; } /*判断共享内存的名字长度是否一样*/ if (shm_zone[i].shm.name.len != oshm_zone[n].shm.name.len) { continue; } /*判断共享内存的名字是否一样*/ if (ngx_strncmp(shm_zone[i].shm.name.data, oshm_zone[n].shm.name.data, shm_zone[i].shm.name.len) != 0) { continue; } /*判断tag size是否一样,并且共享内存是可重用的*/ if (shm_zone[i].tag == oshm_zone[n].tag && shm_zone[i].shm.size == oshm_zone[n].shm.size && !shm_zone[i].noreuse) { shm_zone[i].shm.addr = oshm_zone[n].shm.addr; #if (NGX_WIN32) shm_zone[i].shm.handle = oshm_zone[n].shm.handle; #endif /*找到了可重用的共享内存,进行初始化*/ if (shm_zone[i].init(&shm_zone[i], oshm_zone[n].data) != NGX_OK) { goto failed; } goto shm_zone_found; } ngx_shm_free(&oshm_zone[n].shm); break; } /*程序执行到这里说明没有找到可重用的共享内存,需要重新申请*/ /*申请共享内存*/ if (ngx_shm_alloc(&shm_zone[i].shm) != NGX_OK) { goto failed; } /*初始化shm共享内存池*/ if (ngx_init_zone_pool(cycle, &shm_zone[i]) != NGX_OK) { goto failed; } /*创建并初始化好共享内存后调用模块实现的初始化方法*/ if (shm_zone[i].init(&shm_zone[i], NULL) != NGX_OK) { goto failed; } shm_zone_found: continue; } /* handle the listening sockets */ /*old_cycle->listening.nelts不为0,表示平滑升级时从旧版本nginx服务中继承了监听端口*/ if (old_cycle->listening.nelts) { ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { ls[i].remain = 0; //ngx_listening_t->remain=0表示正常关闭原来打开的端口,这里表示关闭临时cycle打开的监听端口 } nls = cycle->listening.elts; for (n = 0; n < cycle->listening.nelts; n++) { for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].ignore) { //ignore为1表示跳过设置该套接字 continue; } if (ls[i].remain) { //remain为1表示不关闭原先打开的端口(上面已经该临时cycle的该字段置为0) continue; } /*套接字类型不匹配*/ if (ls[i].type != nls[n].type) { continue; } /*判断sockadd是否一致*/ if (ngx_cmp_sockaddr(nls[n].sockaddr, nls[n].socklen, ls[i].sockaddr, ls[i].socklen, 1) == NGX_OK) { /*保存旧cycle监听的结构体,并将remian置为1*/ nls[n].fd = ls[i].fd; nls[n].previous = &ls[i]; ls[i].remain = 1; if (ls[i].backlog != nls[n].backlog) { nls[n].listen = 1; } #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) /* * FreeBSD, except the most recent versions, * could not remove accept filter */ nls[n].deferred_accept = ls[i].deferred_accept; if (ls[i].accept_filter && nls[n].accept_filter) { if (ngx_strcmp(ls[i].accept_filter, nls[n].accept_filter) != 0) { nls[n].delete_deferred = 1; nls[n].add_deferred = 1; } } else if (ls[i].accept_filter) { nls[n].delete_deferred = 1; } else if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept && !nls[n].deferred_accept) { nls[n].delete_deferred = 1; } else if (ls[i].deferred_accept != nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_REUSEPORT) if (nls[n].reuseport && !ls[i].reuseport) { nls[n].add_reuseport = 1; } #endif break; } } if (nls[n].fd == (ngx_socket_t) -1) { nls[n].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif } } } else { ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { ls[i].open = 1; //当前监听句柄有效,且不关闭 #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (ls[i].accept_filter) { ls[i].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept) { ls[i].add_deferred = 1; } #endif } } /*创建套接字,绑定并监听地址和端口*/ if (ngx_open_listening_sockets(cycle) != NGX_OK) { goto failed; } if (!ngx_test_config) { ngx_configure_listening_sockets(cycle); /*设置套接字属性,如rcvbuf、sndbuf*/ } /* commit the new cycle configuration */ if (!ngx_use_stderr) { (void) ngx_log_redirect_stderr(cycle); } pool->log = cycle->log; /*调用所有模块的init_module方法*/ if (ngx_init_modules(cycle) != NGX_OK) { /* fatal */ exit(1); } /* close and delete stuff that lefts from an old cycle */ /* free the unnecessary shared memory */ /*释放临时cycle中不再使用的共享内存*/ opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (i = 0; /* void */ ; i++) { if (i >= opart->nelts) { if (opart->next == NULL) { goto old_shm_zone_done; } opart = opart->next; oshm_zone = opart->elts; i = 0; } part = &cycle->shared_memory.part; shm_zone = part->elts; for (n = 0; /* void */ ; n++) { if (n >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; n = 0; } /*判断共享内存是否重用*/ if (oshm_zone[i].shm.name.len == shm_zone[n].shm.name.len && ngx_strncmp(oshm_zone[i].shm.name.data, shm_zone[n].shm.name.data, oshm_zone[i].shm.name.len) == 0) { goto live_shm_zone; } } ngx_shm_free(&oshm_zone[i].shm); live_shm_zone: continue; } old_shm_zone_done: /* close the unnecessary listening sockets */ /*关闭临时cycle中打开的且不重用的socket句柄*/ ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].remain || ls[i].fd == (ngx_socket_t) -1) { continue; } /*关闭socket句柄*/ if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " listening socket on %V failed", &ls[i].addr_text); } #if (NGX_HAVE_UNIX_DOMAIN) if (ls[i].sockaddr->sa_family == AF_UNIX) { u_char *name; name = ls[i].addr_text.data + sizeof("unix:") - 1; ngx_log_error(NGX_LOG_WARN, cycle->log, 0, "deleting socket %s", name); if (ngx_delete_file(name) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno, ngx_delete_file_n " %s failed", name); } } #endif } /* close the unnecessary open files */ /*关闭临时cycle中打开的文件*/ part = &old_cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } /*关闭文件句柄*/ if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } /*释放临时内存池*/ ngx_destroy_pool(conf.temp_pool); /*如果是第一次加载,则满足ngx_is_init_cycle();如果是reload热启动,则原来的nginx的进程满足ngx_process == NGX_PROCESS_MASTER*/ if (ngx_process == NGX_PROCESS_MASTER || ngx_is_init_cycle(old_cycle)) { /* * perl_destruct() frees environ, if it is not the same as it was at * perl_construct() time, therefore we save the previous cycle * environment before ngx_conf_parse() where it will be changed. */ env = environ; environ = senv; /*释放临时cycle中的内存池*/ ngx_destroy_pool(old_cycle->pool); cycle->old_cycle = NULL; environ = env; return cycle; } if (ngx_temp_pool == NULL) { ngx_temp_pool = ngx_create_pool(128, cycle->log); if (ngx_temp_pool == NULL) { ngx_log_error(NGX_LOG_EMERG, cycle->log, 0, "could not create ngx_temp_pool"); exit(1); } n = 10; ngx_old_cycles.elts = ngx_pcalloc(ngx_temp_pool, n * sizeof(ngx_cycle_t *)); if (ngx_old_cycles.elts == NULL) { exit(1); } ngx_old_cycles.nelts = 0; ngx_old_cycles.size = sizeof(ngx_cycle_t *); ngx_old_cycles.nalloc = n; ngx_old_cycles.pool = ngx_temp_pool; ngx_cleaner_event.handler = ngx_clean_old_cycles; ngx_cleaner_event.log = cycle->log; ngx_cleaner_event.data = &dumb; dumb.fd = (ngx_socket_t) -1; } ngx_temp_pool->log = cycle->log; old = ngx_array_push(&ngx_old_cycles); if (old == NULL) { exit(1); } *old = old_cycle; if (!ngx_cleaner_event.timer_set) { ngx_add_timer(&ngx_cleaner_event, 30000); ngx_cleaner_event.timer_set = 1; } return cycle; failed: if (!ngx_is_init_cycle(old_cycle)) { old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (old_ccf->environment) { environ = old_ccf->environment; } } /* rollback the new cycle configuration */ /*关闭打开的文件*/ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } if (ngx_test_config) { ngx_destroy_cycle_pools(&conf); return NULL; } /*关闭打开的监听端口,为啥要关闭*/ ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { if (ls[i].fd == (ngx_socket_t) -1 || !ls[i].open) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " %V failed", &ls[i].addr_text); } } /*释放内存池*/ ngx_destroy_cycle_pools(&conf); return NULL; }
int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; ngx_debug_init(); if (ngx_strerror_init() != NGX_OK) { return 1; } //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) { return 1; } if (ngx_show_version) { ngx_write_stderr("nginx version: " NGINX_VER NGX_LINEFEED); if (ngx_show_help) { ngx_write_stderr( "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" NGX_LINEFEED NGX_LINEFEED "Options:" NGX_LINEFEED " -?,-h : this help" NGX_LINEFEED " -v : show version and exit" NGX_LINEFEED " -V : show version and configure options then exit" NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED " -s signal : send signal to a master process: " "stop, quit, reopen, reload" NGX_LINEFEED #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" NGX_LINEFEED #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED " -g directives : set global directives out of configuration " "file" NGX_LINEFEED NGX_LINEFEED ); } if (ngx_show_configure) { ngx_write_stderr( #ifdef NGX_COMPILER "built by " NGX_COMPILER NGX_LINEFEED #endif #if (NGX_SSL) #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME "TLS SNI support enabled" NGX_LINEFEED #else "TLS SNI support disabled" NGX_LINEFEED #endif #endif "configure arguments:" NGX_CONFIGURE NGX_LINEFEED); } if (!ngx_test_config) { return 0; } } /* TODO */ ngx_max_sockets = -1; //初始化nginx环境的当前时间 ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); #endif //master pid, 获取当前进程ID ngx_pid = ngx_getpid(); // 初始化日志,如打开日志文件 log = ngx_log_init(ngx_prefix); if (log == NULL) { return 1; } /* STUB */ #if (NGX_OPENSSL) ngx_ssl_init(log); //是否开启了ssl,如果开启在这里进行初始化 #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cycle创建一个1024B的内存池 init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } // 将命令行参数保存到ngx_os_argv、ngx_argc以及ngx_argv这几个全局的变量中。 // 这算是一个备份存储,方便以后master进程做热代码替换之用。 if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } // 初始化init_cycle中的一些如: conf_file,prefix,conf_prefix等字段 if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } // 完成操作系统的一些信息获取,如内存页面大小、系统限制资源,ngx_pagesize,ngx_cacheline_size,最大连接数ngx_max_sockets等 // 所有的这些资源都将会被保存在对应的全局变量中,因此后续访问将会很便利。 if (ngx_os_init(log) != NGX_OK) {// 这个ngx_os_init在不同操作系统调用不同的函数 return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() */ // 初始化一个做循环冗余校验的表,由此可以看出后续的循环冗余校验将采用高效的查表法。 if (ngx_crc32_table_init() != NGX_OK) { return 1; } // 通过环境变量NGINX完成socket的继承,继承来的socket将会放到init_cycle的listening数组中。 // 在NGINX环境变量中,每个socket中间用冒号或分号隔开。完成继承同时设置全局变量ngx_inherited为1。 if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } // 计算模块个数,并且设置各个模块顺序(索引) // 这里面的ngx_modules会有非常多的模块,编译后在objs下面会生成一个ngx_modules.c文件,里边列出了所有使用的模块 // 默认有44个模块 ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { ngx_modules[i]->index = ngx_max_module++; } // 对ngx_cycle结构进行初始化,这里是nginx启动核心之处, 会将很多东西放在init_cycle中 // 详细见ngx_cycle.c中的 ngx_init_cycle方法 cycle = ngx_init_cycle(&init_cycle); if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } // 检查是否有设置信号处理,如有,进入ngx_signal_process处理 if (ngx_signal) { return ngx_signal_process(cycle, ngx_signal); } ngx_os_status(cycle->log); ngx_cycle = cycle; // 获取核心模块的配置信息 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) // 注册一堆信号处理程序,需要注册的信号及相应的信号处理函数被放在一个类型为ngx_signal_t的数组signals中。 // 数组定义在src/os/unix/ngx_process.c中。ngx_signal_t结构类型定义了信号值,信号名字,信号对应动作名以及信号处理函数。 if (ngx_init_signals(cycle->log) != NGX_OK) { return 1; } // ngx_daemon肯定就是用来实现守护进程的函数了, 有需要写server程序的,可以直接copy这段代码实现守护进程。 // 代码实现位于 ./src/os/unix/ngx_daemon.c if (!ngx_inherited && ccf->daemon) { if (ngx_daemon(cycle->log) != NGX_OK) { return 1; } ngx_daemonized = 1; } if (ngx_inherited) { ngx_daemonized = 1; } #endif // 玩过Nginx的人都知道,Nginx启动后有一个记录进程id的文件,这个文件里面就一个pid。 // 原来这个pid就是在这个地方记录下来的。查看ngx_create_pidfile函数可以看到这样的一行代码 // 其中第一个参数为pid文件名称, 从核心配置文件中读取到的 if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } if (cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); 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); //单进程 } else { ngx_master_process_cycle(cycle); //多进程,master进程进入这个,这个函数在不同操作系统有不同实现。 } 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; }
//初始化cycle ngx_cycle_t * ngx_init_cycle(ngx_cycle_t *old_cycle) { void *rv; char **senv, **env; ngx_uint_t i, n; ngx_log_t *log; ngx_time_t *tp; ngx_conf_t conf;//与nginx.conf配置文件相关的一个变量,配置文件的解析都是围绕这个变量进行 ngx_pool_t *pool; ngx_cycle_t *cycle, **old; ngx_shm_zone_t *shm_zone, *oshm_zone; ngx_list_part_t *part, *opart; ngx_open_file_t *file; ngx_listening_t *ls, *nls; ngx_core_conf_t *ccf, *old_ccf; ngx_core_module_t *module; char hostname[NGX_MAXHOSTNAMELEN]; ngx_timezone_update(); /* force localtime update with a new timezone */ tp = ngx_timeofday(); // 这个宏就是取出之前的ngx_cache_time tp->sec = 0; ngx_time_update(); //这里又进行了一次time更新 log = old_cycle->log; //创建内存池,并把日志和它关联 ,创建固定大小的内存池:16384 pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (pool == NULL) { return NULL; } pool->log = log; //分配内存,并把内存池、日志、旧信息以及路径进行了设置。这两段代码所的是创建一个内存池,然后在内存池上为cycle变量分配一个存储空间。 cycle = ngx_pcalloc(pool, sizeof(ngx_cycle_t)); if (cycle == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pool = pool; cycle->log = log; cycle->new_log.log_level = NGX_LOG_ERR; cycle->old_cycle = old_cycle; //配置路径的前缀 cycle->conf_prefix.len = old_cycle->conf_prefix.len; cycle->conf_prefix.data = ngx_pstrdup(pool, &old_cycle->conf_prefix); if (cycle->conf_prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } //系统路径的前缀 cycle->prefix.len = old_cycle->prefix.len; cycle->prefix.data = ngx_pstrdup(pool, &old_cycle->prefix); if (cycle->prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } //配置文件路径 cycle->conf_file.len = old_cycle->conf_file.len; cycle->conf_file.data = ngx_pnalloc(pool, old_cycle->conf_file.len + 1); if (cycle->conf_file.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_cpystrn(cycle->conf_file.data, old_cycle->conf_file.data, old_cycle->conf_file.len + 1); //配置参数设定 cycle->conf_param.len = old_cycle->conf_param.len; cycle->conf_param.data = ngx_pstrdup(pool, &old_cycle->conf_param); if (cycle->conf_param.data == NULL) { ngx_destroy_pool(pool); return NULL; } //文件路径分配空间并初始化 ,如果old_cycle默认没有指定,则大小为10 n = old_cycle->pathes.nelts ? old_cycle->pathes.nelts : 10; cycle->pathes.elts = ngx_pcalloc(pool, n * sizeof(ngx_path_t *)); if (cycle->pathes.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pathes.nelts = 0; cycle->pathes.size = sizeof(ngx_path_t *); cycle->pathes.nalloc = n; cycle->pathes.pool = pool; // 每个打开的文件都会放到cycle中的open_files中。每个共享内存段都会放到shared_memory链表中 //如果原来结构中有文件,那么直接统计原来打开的文件,否则默认20 if (old_cycle->open_files.part.nelts) { n = old_cycle->open_files.part.nelts; for (part = old_cycle->open_files.part.next; part; part = part->next) { n += part->nelts; } } else { n = 20; } //根据数量初始化,初始化open_files if (ngx_list_init(&cycle->open_files, pool, n, sizeof(ngx_open_file_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } //如果原来结构中共享内存,那么直接统计原来共享内存数,否则默认20 if (old_cycle->shared_memory.part.nelts) { n = old_cycle->shared_memory.part.nelts; for (part = old_cycle->shared_memory.part.next; part; part = part->next) { n += part->nelts; } } else { n = 1; } //根据数量初始化,初始化shared_memory if (ngx_list_init(&cycle->shared_memory, pool, n, sizeof(ngx_shm_zone_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } //创建监听者,并初始化 n = old_cycle->listening.nelts ? old_cycle->listening.nelts : 10; cycle->listening.elts = ngx_pcalloc(pool, n * sizeof(ngx_listening_t)); if (cycle->listening.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->listening.nelts = 0; cycle->listening.size = sizeof(ngx_listening_t); cycle->listening.nalloc = n; cycle->listening.pool = pool; ngx_queue_init(&cycle->reusable_connections_queue); //创建所有模块配置的指针, 这里的ngx_max_module在nginx.c中计算过了 cycle->conf_ctx = ngx_pcalloc(pool, ngx_max_module * sizeof(void *)); if (cycle->conf_ctx == NULL) { ngx_destroy_pool(pool); return NULL; } //获取主机名,设置 hostname,这个时候hostname就是机器名,比如“yejianfeng-D1” if (gethostname(hostname, NGX_MAXHOSTNAMELEN) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "gethostname() failed"); ngx_destroy_pool(pool); return NULL; } /* on Linux gethostname() silently truncates name that does not fit */ hostname[NGX_MAXHOSTNAMELEN - 1] = '\0'; cycle->hostname.len = ngx_strlen(hostname); cycle->hostname.data = ngx_pnalloc(pool, cycle->hostname.len); if (cycle->hostname.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_strlow(cycle->hostname.data, (u_char *) hostname, cycle->hostname.len); //将主机名变为消息,所以这里主机名是不分大小写的 //调用核心模块的配置创建函数, cycle->conf_ctx 中对应的指针指向创建的配置 //创建所有core module的configure.它通过调用每个core module的ngx_xxx_module_create_conf方法,来创建对应的conf, //然后将这个conf对象保存在全局的conf_ctx中 for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { //非核心模块直接跳过 continue; } //这里只对核心模块进行处理,核心模块就是ngx_core_module,ngx_errlog_module,ngx_events_module和ngx_http_module //实际上只有ngx_core_module_create_conf //得到core modules module = ngx_modules[i]->ctx; //如果create_conf存在,则直接创建config if (module->create_conf) { rv = module->create_conf(cycle); //对每个模块调用模块内部的钩子ngx_xxx_module_create_conf,当然第一个模块是core if (rv == NULL) { ngx_destroy_pool(pool); return NULL; } //保存config,这里看到conf_ctx里面就是放对应模块的main conf. cycle->conf_ctx[ngx_modules[i]->index] = rv; } } senv = environ; //对指令结构进行初始化:参数,内存池 ngx_memzero(&conf, sizeof(ngx_conf_t)); /* STUB: init array ? */ conf.args = ngx_array_create(pool, 10, sizeof(ngx_str_t)); if (conf.args == NULL) { ngx_destroy_pool(pool); return NULL; } conf.temp_pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (conf.temp_pool == NULL) { ngx_destroy_pool(pool); return NULL; } //指令结果赋值 conf.ctx = cycle->conf_ctx; conf.cycle = cycle; conf.pool = pool; conf.log = log; conf.module_type = NGX_CORE_MODULE;//注意,一开始命令的类型就是MAIN,并且模块类型是core。 conf.cmd_type = NGX_MAIN_CONF; #if 0 log->log_level = NGX_LOG_DEBUG_ALL; #endif if (ngx_conf_param(&conf) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } //开始解析配置文件了,解析配置文件它会一行行读取,然后如果遇到指令 //则会查找到对应的ngx_command_t对象,然后执行对应的回调set方法。这里所有动作都在ngx_conf_parse这个函数中进行. //这函数是立即模块的核心函数,对配置文件边解析边处理 if (ngx_conf_parse(&conf, &cycle->conf_file) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_test_config && !ngx_quiet_mode) { ngx_log_stderr(0, "the configuration file %s syntax is ok", cycle->conf_file.data); } //当配置文件解析完毕后,就初始化core module的config for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } module = ngx_modules[i]->ctx; //调用ngx_xxx_module_init_conf if (module->init_conf) { if (module->init_conf(cycle, cycle->conf_ctx[ngx_modules[i]->index]) == NGX_CONF_ERROR) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } } } if (ngx_process == NGX_PROCESS_SIGNALLER) { return cycle; } ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ngx_test_config) { if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } } else if (!ngx_is_init_cycle(old_cycle)) { /* * we do not create the pid file in the first ngx_init_cycle() call * because we need to write the demonized process pid */ old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (ccf->pid.len != old_ccf->pid.len || ngx_strcmp(ccf->pid.data, old_ccf->pid.data) != 0) { /* new pid file name */ if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } ngx_delete_pidfile(old_cycle); } } if (ngx_test_lockfile(cycle->lock_file.data, log) != NGX_OK) { goto failed; } // 创建client_body_temp,proxy_temp,fastcgi_temp,uwsgi_temp,scgi_temp这几个目录 if (ngx_create_pathes(cycle, ccf->user) != NGX_OK) { goto failed; } if (cycle->new_log.file == NULL) { cycle->new_log.file = ngx_conf_open_file(cycle, &error_log); if (cycle->new_log.file == NULL) { goto failed; } } /* open the new files */ part = &cycle->open_files.part; file = part->elts; // 打开所有文件,这时候file里面不仅有存文件路径,而且存储了文件描述符等信息。 for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].name.len == 0) { continue; } file[i].fd = ngx_open_file(file[i].name.data, NGX_FILE_APPEND, NGX_FILE_CREATE_OR_OPEN, NGX_FILE_DEFAULT_ACCESS); ngx_log_debug3(NGX_LOG_DEBUG_CORE, log, 0, "log: %p %d \"%s\"", &file[i], file[i].fd, file[i].name.data); if (file[i].fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_open_file_n " \"%s\" failed", file[i].name.data); goto failed; } #if !(NGX_WIN32) if (fcntl(file[i].fd, F_SETFD, FD_CLOEXEC) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "fcntl(FD_CLOEXEC) \"%s\" failed", file[i].name.data); goto failed; } #endif } cycle->log = &cycle->new_log; pool->log = &cycle->new_log; /* create shared memory */ part = &cycle->shared_memory.part; shm_zone = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; i = 0; } if (shm_zone[i].shm.size == 0) { ngx_log_error(NGX_LOG_EMERG, log, 0, "zero size shared memory zone \"%V\"", &shm_zone[i].shm.name); goto failed; } shm_zone[i].shm.log = cycle->log; opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (n = 0; /* void */ ; n++) { if (n >= opart->nelts) { if (opart->next == NULL) { break; } opart = opart->next; oshm_zone = opart->elts; n = 0; } if (shm_zone[i].shm.name.len != oshm_zone[n].shm.name.len) { continue; } if (ngx_strncmp(shm_zone[i].shm.name.data, oshm_zone[n].shm.name.data, shm_zone[i].shm.name.len) != 0) { continue; } if (shm_zone[i].shm.size == oshm_zone[n].shm.size) { shm_zone[i].shm.addr = oshm_zone[n].shm.addr; if (shm_zone[i].init(&shm_zone[i], oshm_zone[n].data) != NGX_OK) { goto failed; } goto shm_zone_found; } ngx_shm_free(&oshm_zone[n].shm); break; } //初始化所有创建的共享内存 if (ngx_shm_alloc(&shm_zone[i].shm) != NGX_OK) { goto failed; } if (ngx_init_zone_pool(cycle, &shm_zone[i]) != NGX_OK) { goto failed; } if (shm_zone[i].init(&shm_zone[i], NULL) != NGX_OK) { goto failed; } shm_zone_found: continue; } /* handle the listening sockets */ if (old_cycle->listening.nelts) { ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { ls[i].remain = 0; } nls = cycle->listening.elts; for (n = 0; n < cycle->listening.nelts; n++) { for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].ignore) { continue; } if (ngx_cmp_sockaddr(nls[n].sockaddr, ls[i].sockaddr) == NGX_OK) { nls[n].fd = ls[i].fd; nls[n].previous = &ls[i]; ls[i].remain = 1; if (ls[n].backlog != nls[i].backlog) { nls[n].listen = 1; } #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) /* * FreeBSD, except the most recent versions, * could not remove accept filter */ nls[n].deferred_accept = ls[i].deferred_accept; if (ls[i].accept_filter && nls[n].accept_filter) { if (ngx_strcmp(ls[i].accept_filter, nls[n].accept_filter) != 0) { nls[n].delete_deferred = 1; nls[n].add_deferred = 1; } } else if (ls[i].accept_filter) { nls[n].delete_deferred = 1; } else if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[n].deferred_accept && !nls[n].deferred_accept) { nls[n].delete_deferred = 1; } else if (ls[i].deferred_accept != nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif break; } } if (nls[n].fd == -1) { nls[n].open = 1; } } } else { ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { ls[i].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (ls[i].accept_filter) { ls[i].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept) { ls[i].add_deferred = 1; } #endif } } //listen socket的初始化,创建并bind等操作, 打开所有的监听套接口(依次进行socket,bind,listen) if (ngx_open_listening_sockets(cycle) != NGX_OK) { goto failed; } if (!ngx_test_config) { ngx_configure_listening_sockets(cycle); } /* commit the new cycle configuration */ if (!ngx_use_stderr && cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); } } pool->log = cycle->log; //调用init_module对所有的模块进行初始化,调用所有模块的ngx_XXX_module_init钩子,比如ngx_event_module_init for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->init_module) { if (ngx_modules[i]->init_module(cycle) != NGX_OK) { /* fatal */ exit(1); } } } /* close and delete stuff that lefts from an old cycle */ // 关闭或删除残留在old_cycle中的资源 /* free the unnecessary shared memory */ opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (i = 0; /* void */ ; i++) { if (i >= opart->nelts) { if (opart->next == NULL) { goto old_shm_zone_done; } opart = opart->next; oshm_zone = opart->elts; i = 0; } part = &cycle->shared_memory.part; shm_zone = part->elts; for (n = 0; /* void */ ; n++) { if (n >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; n = 0; } if (oshm_zone[i].shm.name.len == shm_zone[n].shm.name.len && ngx_strncmp(oshm_zone[i].shm.name.data, shm_zone[n].shm.name.data, oshm_zone[i].shm.name.len) == 0) { goto live_shm_zone; } } ngx_shm_free(&oshm_zone[i].shm); live_shm_zone: continue; } old_shm_zone_done: /* close the unnecessary listening sockets */ ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].remain || ls[i].fd == -1) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " listening socket on %V failed", &ls[i].addr_text); } #if (NGX_HAVE_UNIX_DOMAIN) if (ls[i].sockaddr->sa_family == AF_UNIX) { u_char *name; name = ls[i].addr_text.data + sizeof("unix:") - 1; ngx_log_error(NGX_LOG_WARN, cycle->log, 0, "deleting socket %s", name); if (ngx_delete_file(name) == -1) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno, ngx_delete_file_n " %s failed", name); } } #endif } /* close the unnecessary open files */ part = &old_cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } ngx_destroy_pool(conf.temp_pool); if (ngx_process == NGX_PROCESS_MASTER || ngx_is_init_cycle(old_cycle)) { /* * perl_destruct() frees environ, if it is not the same as it was at * perl_construct() time, therefore we save the previous cycle * environment before ngx_conf_parse() where it will be changed. */ env = environ; environ = senv; ngx_destroy_pool(old_cycle->pool); cycle->old_cycle = NULL; environ = env; return cycle; } if (ngx_temp_pool == NULL) { ngx_temp_pool = ngx_create_pool(128, cycle->log); if (ngx_temp_pool == NULL) { ngx_log_error(NGX_LOG_EMERG, cycle->log, 0, "could not create ngx_temp_pool"); exit(1); } n = 10; ngx_old_cycles.elts = ngx_pcalloc(ngx_temp_pool, n * sizeof(ngx_cycle_t *)); if (ngx_old_cycles.elts == NULL) { exit(1); } ngx_old_cycles.nelts = 0; ngx_old_cycles.size = sizeof(ngx_cycle_t *); ngx_old_cycles.nalloc = n; ngx_old_cycles.pool = ngx_temp_pool; ngx_cleaner_event.handler = ngx_clean_old_cycles; ngx_cleaner_event.log = cycle->log; ngx_cleaner_event.data = &dumb; dumb.fd = (ngx_socket_t) -1; } ngx_temp_pool->log = cycle->log; old = ngx_array_push(&ngx_old_cycles); if (old == NULL) { exit(1); } *old = old_cycle; if (!ngx_cleaner_event.timer_set) { ngx_add_timer(&ngx_cleaner_event, 30000); ngx_cleaner_event.timer_set = 1; } return cycle; failed: if (!ngx_is_init_cycle(old_cycle)) { old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (old_ccf->environment) { environ = old_ccf->environment; } } /* rollback the new cycle configuration */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } if (ngx_test_config) { ngx_destroy_cycle_pools(&conf); return NULL; } ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { if (ls[i].fd == -1 || !ls[i].open) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " %V failed", &ls[i].addr_text); } } ngx_destroy_cycle_pools(&conf); return NULL; }
int ngx_cdecl main(int argc, char *const *argv) { char *p; ssize_t n; ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; #if (NGX_FREEBSD) ngx_debug_init(); #endif /* TODO */ ngx_max_sockets = -1; ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); #endif ngx_pid = ngx_getpid(); log = ngx_log_init(); if (log == NULL) { return 1; } /* STUB */ #if (NGX_OPENSSL) ngx_ssl_init(log); #endif /* init_cycle->log is required for signal handlers and ngx_getopt() */ ngx_memzero(&init_cycle, sizeof(ngx_cycle_t)); init_cycle.log = log; ngx_cycle = &init_cycle; init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } if (ngx_getopt(&init_cycle, argc, ngx_argv) != NGX_OK) { return 1; } if (ngx_show_version) { p = "nginx version: " NGINX_VER CRLF; n = sizeof("nginx version: " NGINX_VER CRLF) - 1; if (ngx_write_fd(ngx_stderr_fileno, p, n) != n) { return 1; } if (ngx_show_configure) { #ifdef NGX_COMPILER p = "built by " NGX_COMPILER CRLF; n = sizeof("built by " NGX_COMPILER CRLF) - 1; if (ngx_write_fd(ngx_stderr_fileno, p, n) != n) { return 1; } #endif p = "configure arguments:" NGX_CONFIGURE CRLF; n = sizeof("configure arguments:" NGX_CONFIGURE CRLF) - 1; if (ngx_write_fd(ngx_stderr_fileno, p, n) != n) { return 1; } } if (!ngx_test_config) { return 0; } } if (ngx_test_config) { log->log_level = NGX_LOG_INFO; } 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_error(NGX_LOG_EMERG, log, 0, "the configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { ngx_log_error(NGX_LOG_INFO, log, 0, "the configuration file %s was tested successfully", cycle->conf_file.data); return 0; } ngx_os_status(cycle->log); ngx_cycle = cycle; ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); ngx_process = ccf->master ? NGX_PROCESS_MASTER : NGX_PROCESS_SINGLE; #if (NGX_WIN32) #if 0 TODO: if (ccf->run_as_service) { if (ngx_service(cycle->log) != NGX_OK) { return 1; } return 0; } #endif #else 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_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } #endif if (ngx_process == NGX_PROCESS_MASTER) { ngx_master_process_cycle(cycle); } else { ngx_single_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_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; }
// 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; }
int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; ngx_debug_init(); // posix 系统上为空 // 把0到GX_SYS_NERR的strerror信息存到ngx_sys_errlist里 // 以后错误信息直接从这儿取 if (ngx_strerror_init() != NGX_OK) { return 1; } // 解析命令行 if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } // 显示帮助信息 if (ngx_show_version) { ngx_write_stderr("nginx version: " NGINX_VER NGX_LINEFEED); if (ngx_show_help) { ngx_write_stderr( "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" NGX_LINEFEED NGX_LINEFEED "Options:" NGX_LINEFEED " -?,-h : this help" NGX_LINEFEED " -v : show version and exit" NGX_LINEFEED " -V : show version and configure options then exit" NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED " -s signal : send signal to a master process: " "stop, quit, reopen, reload" NGX_LINEFEED #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" NGX_LINEFEED #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED " -g directives : set global directives out of configuration " "file" NGX_LINEFEED NGX_LINEFEED ); } // 显示编译参数 if (ngx_show_configure) { ngx_write_stderr( #ifdef NGX_COMPILER "built by " NGX_COMPILER NGX_LINEFEED #endif #if (NGX_SSL) #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME "TLS SNI support enabled" NGX_LINEFEED #else "TLS SNI support disabled" NGX_LINEFEED #endif #endif "configure arguments:" NGX_CONFIGURE NGX_LINEFEED); } if (!ngx_test_config) { return 0; } } /* TODO */ ngx_max_sockets = -1; ngx_time_init(); // 初始化时钟 #if (NGX_PCRE) ngx_regex_init(); #endif ngx_pid = ngx_getpid(); log = ngx_log_init(ngx_prefix); // 初始化错误日志,打开错误日志文件 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; } // 把命令行参数保存在 os/unix/ngx_process.c:30:char **ngx_argv; if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } // 决定NGINX运行的目录 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; } // 通过环境变量NGINX完成socket的继承,继承来的socket将会放到init_cycle的listening数组中。同时可以读取master进程传递的平滑升级信息等等 if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } //初始化所有模块的index信息,即对所有模块进行编号 //ngx_modules数却是在自动编译的时候生成的,位于objs/ngx_modules.c文件中 ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { ngx_modules[i]->index = ngx_max_module++; } // 初始化重点都在这儿了 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; } // nginx -t 测试配置文件 if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } // nginx -s 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; }
//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 int ngx_cdecl //ngx_cdecl宏用于显式声明应使用的调用约定,在跨平台移植时有用,在linux版本的nginx程序中,该宏被定义为空 main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; //保存日志结构 ngx_cycle_t *cycle, init_cycle; //初始化时的主结构体,在平滑升级服务器时,init_cycle负责升级前的信息,cycle负责升级后的信息 ngx_core_conf_t *ccf; //保存配置上下文 #if (NGX_FREEBSD) ngx_debug_init(); //ngx_debug_init在FreeBSD和MacOSX平台有执行 #endif //ngx_strerror_init 用于初始化nginx服务器自定义的标准错误输出列表 ready the ngx_sys_errlist 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) { return 1; } if (ngx_show_version) {//没有解析到 -v 不执行 ngx_write_stderr("nginx version: " NGINX_VER NGX_LINEFEED); if (ngx_show_help) { ngx_write_stderr( "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" NGX_LINEFEED NGX_LINEFEED "Options:" NGX_LINEFEED " -?,-h : this help" NGX_LINEFEED " -v : show version and exit" NGX_LINEFEED " -V : show version and configure options then exit" NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED " -s signal : send signal to a master process: " "stop, quit, reopen, reload" NGX_LINEFEED #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" NGX_LINEFEED #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED " -g directives : set global directives out of configuration " "file" NGX_LINEFEED NGX_LINEFEED ); } if (ngx_show_configure) { ngx_write_stderr( #ifdef NGX_COMPILER "built by " NGX_COMPILER NGX_LINEFEED #endif #if (NGX_SSL) //如果支持SSL #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME "TLS SNI support enabled" NGX_LINEFEED #else "TLS SNI support disabled" NGX_LINEFEED #endif #endif "configure arguments:" NGX_CONFIGURE NGX_LINEFEED); } //判断是否对nginx配置文件进行语法检查 if (!ngx_test_config) { return 0; } } /* TODO */ ngx_max_sockets = -1; //初始化nginx环境的当前时间 ngx_time_init(); #if (NGX_PCRE) //支持正则表达式 ngx_regex_init();//ngx_regex_malloc.c #endif //master pid, 获取当前进程ID ngx_pid = ngx_getpid(); // 初始化日志,如打开日志文件//log = ngx_log_t 里面的ngx_open_file_t *file; log = ngx_log_init(ngx_prefix); if (log == NULL) { return 1; } /* STUB */ #if (NGX_OPENSSL) ngx_ssl_init(log); //是否开启了ssl,如果开启在这里进行初始化 #endif /* * init_cycle->log is required for signal handlers and * ngx_process_options() */ //内存管理初始化 ngx_memzero(&init_cycle, sizeof(ngx_cycle_t)); init_cycle.log = log; ngx_cycle = &init_cycle; // 为cycle创建一个1024B的内存池 init_cycle.pool = ngx_create_pool(1024, log);//分配的size 要减去ngx_pool_t结构体自身的内存所占大小 if (init_cycle.pool == NULL) { return 1; } // 保存参数到全局变量中 if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) {//ngx_argv return 1; } // 初始化init_cycle中的一些如: conf_file,prefix,conf_prefix等字段 if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } // 初始化系统相关变量,如内存页面大小ngx_pagesize,ngx_cacheline_size,最大连接数ngx_max_sockets等 if (ngx_os_init(log) != NGX_OK) { //ngx_posix_init.c 这个ngx_os_init在不同操作系统调用不同的函数,根据系统参数来优化配置 return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() */ // 初始化CRC表,提高效率,以后就不用计算了,直接用 if (ngx_crc32_table_init() != NGX_OK) {//src/core/ngx_crc32.c:111 return 1; } // 继承sockets,继承来的socket将会放到init_cycle的listening数组 //继承的原因:在nginx服务器升级的情况下,保证web服务的平滑过渡,新的nginx能够继承旧nginx打开的socket if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) {// src/core/nginx.c:442 return 1; } // 计算模块个数,并且设置各个模块顺序(索引) ngx_max_module = 0;// ngx_command_t : http://book.51cto.com/art/201312/420058.htm *commands ngx_module_s :http://my.oschina.net/showcolors/blog/101169 for (i = 0; ngx_modules[i]; i++) { // 这里面的ngx_modules会有非常多的模块,[ngx_core_module,ngx_errlog_module,ngx_conf_moduel] ngx_modules[i]->index = ngx_max_module++;// p ngx_modules[0]->commands->name } // 对ngx_cycle结构进行初始化,这里是nginx启动核心之处! cycle = ngx_init_cycle(&init_cycle);//ngx_cycle.c 44 if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } // 检查是否有设置信号处理,如有,进入ngx_signal_process处理 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) { //如果是daemon模式,本进程变为守护进程 return 1; } ngx_daemonized = 1; } if (ngx_inherited) { ngx_daemonized = 1; } #endif // 创建进程记录文件 if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } if (cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); 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; //下面调用ngx_single_process_cycle或者ngx_master_process_cycle来启动nginx if (ngx_process == NGX_PROCESS_SINGLE) { ngx_single_process_cycle(cycle); //单进程,基本很少用single模式 } else { ngx_master_process_cycle(cycle); //多进程,master进程进入这个,这个函数在不同操作系统有不同实现。 } return 0; }
int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; ngx_debug_init(); if (ngx_strerror_init() != NGX_OK) { return 1; } if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } if (ngx_show_version) { ngx_write_stderr("nginx version: " NGINX_VER NGX_LINEFEED); if (ngx_show_help) { ngx_write_stderr( "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" NGX_LINEFEED NGX_LINEFEED "Options:" NGX_LINEFEED " -?,-h : this help" NGX_LINEFEED " -v : show version and exit" NGX_LINEFEED " -V : show version and configure options then exit" NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED " -s signal : send signal to a master process: " "stop, quit, reopen, reload" NGX_LINEFEED #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" NGX_LINEFEED #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED " -g directives : set global directives out of configuration " "file" NGX_LINEFEED NGX_LINEFEED ); } if (ngx_show_configure) { ngx_write_stderr( #ifdef NGX_COMPILER "built by " NGX_COMPILER NGX_LINEFEED #endif #if (NGX_SSL) #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME "TLS SNI support enabled" NGX_LINEFEED #else "TLS SNI support disabled" NGX_LINEFEED #endif #endif "configure arguments:" NGX_CONFIGURE NGX_LINEFEED); } if (!ngx_test_config) { return 0; } } /* TODO */ ngx_max_sockets = -1; ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); #endif ngx_pid = ngx_getpid(); log = ngx_log_init(ngx_prefix); if (log == NULL) { return 1; } /* STUB */ #if (NGX_OPENSSL) ngx_ssl_init(log); #endif /* * init_cycle->log is required for signal handlers and * ngx_process_options() */ ngx_memzero(&init_cycle, sizeof(ngx_cycle_t)); init_cycle.log = log; ngx_cycle = &init_cycle; init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } if (ngx_os_init(log) != NGX_OK) { return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() */ if (ngx_crc32_table_init() != NGX_OK) { return 1; } if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { ngx_modules[i]->index = ngx_max_module++; } cycle = ngx_init_cycle(&init_cycle); if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } if (ngx_signal) { return ngx_signal_process(cycle, ngx_signal); } ngx_os_status(cycle->log); ngx_cycle = cycle; ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ccf->master && ngx_process == NGX_PROCESS_SINGLE) { ngx_process = NGX_PROCESS_MASTER; } #if !(NGX_WIN32) if (ngx_init_signals(cycle->log) != NGX_OK) { return 1; } if (!ngx_inherited && ccf->daemon) { if (ngx_daemon(cycle->log) != NGX_OK) { return 1; } ngx_daemonized = 1; } if (ngx_inherited) { ngx_daemonized = 1; } #endif if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } if (cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); 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; }
//http://blog.csdn.net/lengzijian/article/details/7575813 ngx_cycle_t * ngx_init_cycle(ngx_cycle_t *old_cycle) { void *rv; char **senv, **env; ngx_uint_t i, n; ngx_log_t *log; ngx_time_t *tp; ngx_conf_t conf; ngx_pool_t *pool; ngx_cycle_t *cycle, **old; ngx_shm_zone_t *shm_zone, *oshm_zone; ngx_list_part_t *part, *opart; ngx_open_file_t *file; ngx_listening_t *ls, *nls; ngx_core_conf_t *ccf, *old_ccf; ngx_core_module_t *module; char hostname[NGX_MAXHOSTNAMELEN]; ngx_timezone_update(); /* force localtime update with a new timezone */ tp = ngx_timeofday(); tp->sec = 0; ngx_time_update(); log = old_cycle->log; pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (pool == NULL) { return NULL; } pool->log = log; cycle = ngx_pcalloc(pool, sizeof(ngx_cycle_t)); if (cycle == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->pool = pool; cycle->log = log; cycle->old_cycle = old_cycle; cycle->conf_prefix.len = old_cycle->conf_prefix.len; cycle->conf_prefix.data = ngx_pstrdup(pool, &old_cycle->conf_prefix); if (cycle->conf_prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->prefix.len = old_cycle->prefix.len; cycle->prefix.data = ngx_pstrdup(pool, &old_cycle->prefix); if (cycle->prefix.data == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->conf_file.len = old_cycle->conf_file.len; cycle->conf_file.data = ngx_pnalloc(pool, old_cycle->conf_file.len + 1); if (cycle->conf_file.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_cpystrn(cycle->conf_file.data, old_cycle->conf_file.data, old_cycle->conf_file.len + 1); cycle->conf_param.len = old_cycle->conf_param.len; cycle->conf_param.data = ngx_pstrdup(pool, &old_cycle->conf_param); if (cycle->conf_param.data == NULL) { ngx_destroy_pool(pool); return NULL; } n = old_cycle->paths.nelts ? old_cycle->paths.nelts : 10; cycle->paths.elts = ngx_pcalloc(pool, n * sizeof(ngx_path_t *)); if (cycle->paths.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->paths.nelts = 0; cycle->paths.size = sizeof(ngx_path_t *); cycle->paths.nalloc = n; cycle->paths.pool = pool; if (old_cycle->open_files.part.nelts) { n = old_cycle->open_files.part.nelts; for (part = old_cycle->open_files.part.next; part; part = part->next) { n += part->nelts; } } else { n = 20; } if (ngx_list_init(&cycle->open_files, pool, n, sizeof(ngx_open_file_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } if (old_cycle->shared_memory.part.nelts) { n = old_cycle->shared_memory.part.nelts; for (part = old_cycle->shared_memory.part.next; part; part = part->next) { n += part->nelts; } } else { n = 1; } //ngx_list_init主要是初始链表的elts,并为其申请内存 if (ngx_list_init(&cycle->shared_memory, pool, n, sizeof(ngx_shm_zone_t)) != NGX_OK) { ngx_destroy_pool(pool); return NULL; } n = old_cycle->listening.nelts ? old_cycle->listening.nelts : 10; cycle->listening.elts = ngx_pcalloc(pool, n * sizeof(ngx_listening_t)); if (cycle->listening.elts == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->listening.nelts = 0; cycle->listening.size = sizeof(ngx_listening_t); cycle->listening.nalloc = n; cycle->listening.pool = pool; //初始化双向链表。主要存储着可反复用的连接ngx_connection_t ngx_queue_init(&cycle->reusable_connections_queue); cycle->conf_ctx = ngx_pcalloc(pool, ngx_max_module * sizeof(void *)); if (cycle->conf_ctx == NULL) { ngx_destroy_pool(pool); return NULL; } if (gethostname(hostname, NGX_MAXHOSTNAMELEN) == -1) {//获取主机名称 ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "gethostname() failed"); ngx_destroy_pool(pool); return NULL; } /* on Linux gethostname() silently truncates name that does not fit */ hostname[NGX_MAXHOSTNAMELEN - 1] = '\0'; cycle->hostname.len = ngx_strlen(hostname); cycle->hostname.data = ngx_pnalloc(pool, cycle->hostname.len); if (cycle->hostname.data == NULL) { ngx_destroy_pool(pool); return NULL; } ngx_strlow(cycle->hostname.data, (u_char *) hostname, cycle->hostname.len); //调用全部NGX_CORE_MODULE的create_conf构建配置结构体。并保存在conf_ctx数组里面 for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { //event 和http 和core 三个module continue; } //上下文操作 //static ngx_core_module_t ngx_events_module_ctx = { //ngx_string("events"), //NULL, //ngx_event_init_conf //}; //static ngx_core_module_t ngx_http_module_ctx = { //ngx_string("http"), //NULL, //NULL //}; //static ngx_core_module_t ngx_core_module_ctx = { // ngx_string("core"), //ngx_core_module_create_conf, // ngx_core_module_init_conf //}; // module = ngx_modules[i]->ctx; //core module 模块只有create 和 init 两个回调函数 其他 if (module->create_conf) { // rv 返回ngx_core_conf_t rv = module->create_conf(cycle); if (rv == NULL) { ngx_destroy_pool(pool); return NULL; } cycle->conf_ctx[ngx_modules[i]->index] = rv; //倒数第二级指针存放的是每个模块的create-conf 的指针 } } senv = environ; ngx_memzero(&conf, sizeof(ngx_conf_t)); /* STUB: init array ? */ conf.args = ngx_array_create(pool, 10, sizeof(ngx_str_t)); if (conf.args == NULL) { ngx_destroy_pool(pool); return NULL; } conf.temp_pool = ngx_create_pool(NGX_CYCLE_POOL_SIZE, log); if (conf.temp_pool == NULL) { ngx_destroy_pool(pool); return NULL; } conf.ctx = cycle->conf_ctx; conf.cycle = cycle; conf.pool = pool; conf.log = log; conf.module_type = NGX_CORE_MODULE; conf.cmd_type = NGX_MAIN_CONF; #if 0 log->log_level = NGX_LOG_DEBUG_ALL; #endif //2.4从命令行和配置文件里把全部配置更新到cycle的conf_ctx中:首先调用ngx_conf_param把命令行中的指令(-g directives)转换为配置结构并把指针增加到cycle.conf_ctx中;接着调用ngx_conf_parse(..,filename)把配置文件里的指令转换为配置结构并把指针增加到cycle.conf_ctx中。 if (ngx_conf_param(&conf) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_conf_parse(&conf, &cycle->conf_file) != NGX_CONF_OK) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } if (ngx_test_config && !ngx_quiet_mode) { ngx_log_stderr(0, "the configuration file %s syntax is ok", cycle->conf_file.data); } //2.5调用全部核心模块的init函数初始化全部核心模块的配置结构体 for (i = 0; ngx_modules[i]; i++) { if (ngx_modules[i]->type != NGX_CORE_MODULE) { continue; } module = ngx_modules[i]->ctx; if (module->init_conf) {//调用模块的init_conf初始化全部核心模块的配置结构体 if (module->init_conf(cycle, cycle->conf_ctx[ngx_modules[i]->index]) == NGX_CONF_ERROR) { environ = senv; ngx_destroy_cycle_pools(&conf); return NULL; } } } if (ngx_process == NGX_PROCESS_SIGNALLER) { return cycle; } //2.6获得核心模块ngx_core_dodule的配置结构,然后调用ngx_create_pidfile创建pid文件 ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module); if (ngx_test_config) { if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } } else if (!ngx_is_init_cycle(old_cycle)) { /* * we do not create the pid file in the first ngx_init_cycle() call * because we need to write the demonized process pid */ old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (ccf->pid.len != old_ccf->pid.len || ngx_strcmp(ccf->pid.data, old_ccf->pid.data) != 0) { /* new pid file name */ if (ngx_create_pidfile(&ccf->pid, log) != NGX_OK) { goto failed; } ngx_delete_pidfile(old_cycle); } } if (ngx_test_lockfile(cycle->lock_file.data, log) != NGX_OK) { goto failed; } if (ngx_create_paths(cycle, ccf->user) != NGX_OK) { goto failed; } if (ngx_log_open_default(cycle) != NGX_OK) { goto failed; } /* open the new files */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].name.len == 0) { continue; } file[i].fd = ngx_open_file(file[i].name.data, NGX_FILE_APPEND, NGX_FILE_CREATE_OR_OPEN, NGX_FILE_DEFAULT_ACCESS); ngx_log_debug3(NGX_LOG_DEBUG_CORE, log, 0, "log: %p %d \"%s\"", &file[i], file[i].fd, file[i].name.data); if (file[i].fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_open_file_n " \"%s\" failed", file[i].name.data); goto failed; } #if !(NGX_WIN32) if (fcntl(file[i].fd, F_SETFD, FD_CLOEXEC) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "fcntl(FD_CLOEXEC) \"%s\" failed", file[i].name.data); goto failed; } #endif } cycle->log = &cycle->new_log; pool->log = &cycle->new_log; /* create shared memory */ part = &cycle->shared_memory.part; shm_zone = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; i = 0; } if (shm_zone[i].shm.size == 0) { ngx_log_error(NGX_LOG_EMERG, log, 0, "zero size shared memory zone \"%V\"", &shm_zone[i].shm.name); goto failed; } shm_zone[i].shm.log = cycle->log; opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (n = 0; /* void */ ; n++) { if (n >= opart->nelts) { if (opart->next == NULL) { break; } opart = opart->next; oshm_zone = opart->elts; n = 0; } if (shm_zone[i].shm.name.len != oshm_zone[n].shm.name.len) { continue; } if (ngx_strncmp(shm_zone[i].shm.name.data, oshm_zone[n].shm.name.data, shm_zone[i].shm.name.len) != 0) { continue; } if (shm_zone[i].tag == oshm_zone[n].tag && shm_zone[i].shm.size == oshm_zone[n].shm.size && !shm_zone[i].noreuse) { shm_zone[i].shm.addr = oshm_zone[n].shm.addr; #if (NGX_WIN32) shm_zone[i].shm.handle = oshm_zone[n].shm.handle; #endif if (shm_zone[i].init(&shm_zone[i], oshm_zone[n].data) != NGX_OK) { goto failed; } goto shm_zone_found; } ngx_shm_free(&oshm_zone[n].shm); break; } if (ngx_shm_alloc(&shm_zone[i].shm) != NGX_OK) { goto failed; } if (ngx_init_zone_pool(cycle, &shm_zone[i]) != NGX_OK) { goto failed; } if (shm_zone[i].init(&shm_zone[i], NULL) != NGX_OK) { goto failed; } shm_zone_found: continue; } /* handle the listening sockets */ //2.8打开新文件,在第2步的时候提到cycle->open_files这个链表是空的。仅仅是给它预先分配了空间,并没有数据。这里之所以可能会有文件被打开,预计是前面读配置文件的时候,调用各个钩子的过程中,填充了这个链表,把ngx_open_file_t结构变量填充进来(结构体中包括要打开文件的路径信息),接着改动一下cycle的成员:cycle->log = &cycle->new_log;pool->log = &cycle->new_log; //2.9创建共享内存,和open_files类似,在第2步的时候cycle->share_memory也初始化为一个空的链表。也是预分配了空间,假设此时链表中已经被填充了ngx_shm_zone_t结构变量(当中包括须要共享内存的尺寸和标识等信息)。那么这里就会分配共享内存,而且调用合适的初始化钩子初始化分配的共享内存,每块共享内存都会有name标识。这里也会做一些排重,已经分配的就不会再去分配。从对open_files和share_memory的处理过程能够看出,nginx在资源管理上是集中分配的,请求资源的时候分配说明性的结构变量,然后在恰当的时机才去真正分配资源。 //2.10处理listening sockets,cycle->listening是ngx_listening_t结构的数组。把cycle->listening于old_cycle->listening进行比較。设置cycle->listening的一些状态信息。接着调用ngx_open_listening_sockets(cycle)启动cycle->listening中的全部监听socket,循环调用socket,bind,listen完毕服务端监听socket的启动。接着调用ngx_configure_listening_sockets(cycle)配置监听socket。会依据ngx_listening_t中的状态信息设置socket的读写缓存和TCP_DEFER_ACCEPT。 if (old_cycle->listening.nelts) { ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { ls[i].remain = 0; } nls = cycle->listening.elts; for (n = 0; n < cycle->listening.nelts; n++) { for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].ignore) {//标识位为1表示跳过设置ngx_lisenting_t中的套接字。 continue; //为0表示正常初始化套接字 } if (ngx_cmp_sockaddr(nls[n].sockaddr, nls[n].socklen, ls[i].sockaddr, ls[i].socklen, 1) == NGX_OK) { nls[n].fd = ls[i].fd; nls[n].previous = &ls[i]; ls[i].remain = 1;//不关闭已经打开的套接字 if (ls[i].backlog != nls[n].backlog) { nls[n].listen = 1;//套接字已监听 } #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) /* * FreeBSD, except the most recent versions, * could not remove accept filter */ nls[n].deferred_accept = ls[i].deferred_accept; if (ls[i].accept_filter && nls[n].accept_filter) { if (ngx_strcmp(ls[i].accept_filter, nls[n].accept_filter) != 0) { nls[n].delete_deferred = 1; nls[n].add_deferred = 1; } } else if (ls[i].accept_filter) { nls[n].delete_deferred = 1; } else if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept && !nls[n].deferred_accept) { nls[n].delete_deferred = 1; } else if (ls[i].deferred_accept != nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif break; } } if (nls[n].fd == (ngx_socket_t) -1) { nls[n].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (nls[n].accept_filter) { nls[n].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (nls[n].deferred_accept) { nls[n].add_deferred = 1; } #endif } } } else { ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { ls[i].open = 1; #if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER) if (ls[i].accept_filter) { ls[i].add_deferred = 1; } #endif #if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT) if (ls[i].deferred_accept) { ls[i].add_deferred = 1; } #endif } } //在ngx_open_listening_sockets函数的代码中可以看到bind、 //listen等套接字函数的调用。最终创建完的监听套接字就在 //cycle结构体的listening域里 主程序中完成socket的基础设置,完成监听操作。 if (ngx_open_listening_sockets(cycle) != NGX_OK) { goto failed; } if (!ngx_test_config) { ngx_configure_listening_sockets(cycle); } /* commit the new cycle configuration */ if (!ngx_use_stderr) { (void) ngx_log_redirect_stderr(cycle); } pool->log = cycle->log; for (i = 0; ngx_modules[i]; i++) {// 调用全部模块的init_module if (ngx_modules[i]->init_module) { if (ngx_modules[i]->init_module(cycle) != NGX_OK) { /* fatal */ exit(1); } } } /* close and delete stuff that lefts from an old cycle */ /* free the unnecessary shared memory */ opart = &old_cycle->shared_memory.part; oshm_zone = opart->elts; for (i = 0; /* void */ ; i++) { if (i >= opart->nelts) { if (opart->next == NULL) { goto old_shm_zone_done; } opart = opart->next; oshm_zone = opart->elts; i = 0; } part = &cycle->shared_memory.part; shm_zone = part->elts; for (n = 0; /* void */ ; n++) { if (n >= part->nelts) { if (part->next == NULL) { break; } part = part->next; shm_zone = part->elts; n = 0; } if (oshm_zone[i].shm.name.len == shm_zone[n].shm.name.len && ngx_strncmp(oshm_zone[i].shm.name.data, shm_zone[n].shm.name.data, oshm_zone[i].shm.name.len) == 0) { goto live_shm_zone; } } ngx_shm_free(&oshm_zone[i].shm); live_shm_zone: continue; } old_shm_zone_done: /* close the unnecessary listening sockets */ ls = old_cycle->listening.elts; for (i = 0; i < old_cycle->listening.nelts; i++) { if (ls[i].remain || ls[i].fd == (ngx_socket_t) -1) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " listening socket on %V failed", &ls[i].addr_text); } #if (NGX_HAVE_UNIX_DOMAIN) if (ls[i].sockaddr->sa_family == AF_UNIX) { u_char *name; name = ls[i].addr_text.data + sizeof("unix:") - 1; ngx_log_error(NGX_LOG_WARN, cycle->log, 0, "deleting socket %s", name); if (ngx_delete_file(name) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno, ngx_delete_file_n " %s failed", name); } } #endif } /* close the unnecessary open files */ part = &old_cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } ngx_destroy_pool(conf.temp_pool); if (ngx_process == NGX_PROCESS_MASTER || ngx_is_init_cycle(old_cycle)) { /* * perl_destruct() frees environ, if it is not the same as it was at * perl_construct() time, therefore we save the previous cycle * environment before ngx_conf_parse() where it will be changed. */ env = environ; environ = senv; ngx_destroy_pool(old_cycle->pool); cycle->old_cycle = NULL; environ = env; return cycle; } if (ngx_temp_pool == NULL) { ngx_temp_pool = ngx_create_pool(128, cycle->log); if (ngx_temp_pool == NULL) { ngx_log_error(NGX_LOG_EMERG, cycle->log, 0, "could not create ngx_temp_pool"); exit(1); } n = 10; ngx_old_cycles.elts = ngx_pcalloc(ngx_temp_pool, n * sizeof(ngx_cycle_t *)); if (ngx_old_cycles.elts == NULL) { exit(1); } ngx_old_cycles.nelts = 0; ngx_old_cycles.size = sizeof(ngx_cycle_t *); ngx_old_cycles.nalloc = n; ngx_old_cycles.pool = ngx_temp_pool; ngx_cleaner_event.handler = ngx_clean_old_cycles; ngx_cleaner_event.log = cycle->log; ngx_cleaner_event.data = &dumb; dumb.fd = (ngx_socket_t) -1; } ngx_temp_pool->log = cycle->log; old = ngx_array_push(&ngx_old_cycles); if (old == NULL) { exit(1); } *old = old_cycle; if (!ngx_cleaner_event.timer_set) { ngx_add_timer(&ngx_cleaner_event, 30000); ngx_cleaner_event.timer_set = 1; } return cycle; failed: if (!ngx_is_init_cycle(old_cycle)) { old_ccf = (ngx_core_conf_t *) ngx_get_conf(old_cycle->conf_ctx, ngx_core_module); if (old_ccf->environment) { environ = old_ccf->environment; } } /* rollback the new cycle configuration */ part = &cycle->open_files.part; file = part->elts; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; file = part->elts; i = 0; } if (file[i].fd == NGX_INVALID_FILE || file[i].fd == ngx_stderr) { continue; } if (ngx_close_file(file[i].fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, ngx_close_file_n " \"%s\" failed", file[i].name.data); } } if (ngx_test_config) { ngx_destroy_cycle_pools(&conf); return NULL; } ls = cycle->listening.elts; for (i = 0; i < cycle->listening.nelts; i++) { if (ls[i].fd == (ngx_socket_t) -1 || !ls[i].open) { continue; } if (ngx_close_socket(ls[i].fd) == -1) { ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno, ngx_close_socket_n " %V failed", &ls[i].addr_text); } } ngx_destroy_cycle_pools(&conf); return NULL; }
//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 int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; #if (NGX_FREEBSD) ngx_debug_init(); #endif 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) { return 1; } if (ngx_show_version) { ngx_write_stderr("nginx version: " NGINX_VER NGX_LINEFEED); if (ngx_show_help) { ngx_write_stderr( "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" NGX_LINEFEED NGX_LINEFEED "Options:" NGX_LINEFEED " -?,-h : this help" NGX_LINEFEED " -v : show version and exit" NGX_LINEFEED " -V : show version and configure options then exit" NGX_LINEFEED " -t : test configuration and exit" NGX_LINEFEED " -q : suppress non-error messages " "during configuration testing" NGX_LINEFEED " -s signal : send signal to a master process: " "stop, quit, reopen, reload" NGX_LINEFEED #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" NGX_LINEFEED #else " -p prefix : set prefix path (default: NONE)" NGX_LINEFEED #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" NGX_LINEFEED " -g directives : set global directives out of configuration " "file" NGX_LINEFEED NGX_LINEFEED ); } if (ngx_show_configure) { ngx_write_stderr( #ifdef NGX_COMPILER "built by " NGX_COMPILER NGX_LINEFEED #endif #if (NGX_SSL) #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME "TLS SNI support enabled" NGX_LINEFEED #else "TLS SNI support disabled" NGX_LINEFEED #endif #endif "configure arguments:" NGX_CONFIGURE NGX_LINEFEED); } if (!ngx_test_config) { return 0; } } /* TODO */ ngx_max_sockets = -1; //初始化nginx环境的当前时间 ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); #endif //master pid, 获取当前进程ID ngx_pid = ngx_getpid(); // 初始化日志,如打开日志文件 log = ngx_log_init(ngx_prefix); if (log == NULL) { return 1; } /* STUB */ #if (NGX_OPENSSL) ngx_ssl_init(log); //是否开启了ssl,如果开启在这里进行初始化 #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cycle创建一个1024B的内存池 init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } // 保存参数到全局变量中 if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } // 初始化init_cycle中的一些如: conf_file,prefix,conf_prefix等字段 if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } // 初始化系统相关变量,如内存页面大小ngx_pagesize,ngx_cacheline_size,最大连接数ngx_max_sockets等 if (ngx_os_init(log) != NGX_OK) { // 这个ngx_os_init在不同操作系统调用不同的函数 return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() */ // 初始化CRC表,提高效率,以后就不用计算了,直接用 if (ngx_crc32_table_init() != NGX_OK) { return 1; } // 继承sockets,继承来的socket将会放到init_cycle的listening数组 if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } // 计算模块个数,并且设置各个模块顺序(索引) ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { // 这里面的ngx_modules会有非常多的模块,[ngx_core_module,ngx_errlog_module,ngx_conf_moduel] ngx_modules[i]->index = ngx_max_module++; } // 对ngx_cycle结构进行初始化,这里是nginx启动核心之处! cycle = ngx_init_cycle(&init_cycle); if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } // 检查是否有设置信号处理,如有,进入ngx_signal_process处理 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) { //如果是daemon模式,本进程变为守护进程 return 1; } ngx_daemonized = 1; } if (ngx_inherited) { ngx_daemonized = 1; } #endif // 创建进程记录文件 if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } if (cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); 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); //单进程 } else { ngx_master_process_cycle(cycle); //多进程,master进程进入这个,这个函数在不同操作系统有不同实现。 } return 0; }
int ngx_cdecl main(int argc, char *const *argv) { ngx_int_t i; ngx_log_t *log; ngx_cycle_t *cycle, init_cycle; ngx_core_conf_t *ccf; if (ngx_strerror_init() != NGX_OK) { return 1; } //get options input on start up if (ngx_get_options(argc, argv) != NGX_OK) { return 1; } if (ngx_show_version) { ngx_log_stderr(0, "nginx version: " NGINX_VER); if (ngx_show_help) { ngx_log_stderr(0, "Usage: nginx [-?hvVtq] [-s signal] [-c filename] " "[-p prefix] [-g directives]" CRLF CRLF "Options:" CRLF " -?,-h : this help" CRLF " -v : show version and exit" CRLF " -V : show version and configure options then exit" CRLF " -t : test configuration and exit" CRLF " -q : suppress non-error messages " "during configuration testing" CRLF " -s signal : send signal to a master process: " "stop, quit, reopen, reload" CRLF #ifdef NGX_PREFIX " -p prefix : set prefix path (default: " NGX_PREFIX ")" CRLF #else " -p prefix : set prefix path (default: NONE)" CRLF #endif " -c filename : set configuration file (default: " NGX_CONF_PATH ")" CRLF " -g directives : set global directives out of configuration " "file" CRLF ); } if (ngx_show_configure) { #ifdef NGX_COMPILER ngx_log_stderr(0, "built by " NGX_COMPILER); #endif #if (NGX_SSL) #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME ngx_log_stderr(0, "TLS SNI support enabled"); #else ngx_log_stderr(0, "TLS SNI support disabled"); #endif #endif ngx_log_stderr(0, "configure arguments:" NGX_CONFIGURE); } if (!ngx_test_config) { return 0; } } #if (NGX_FREEBSD) ngx_debug_init(); #endif /* TODO */ ngx_max_sockets = -1; //调用ngx_time_init()初始化并更新时间 ngx_time_init(); #if (NGX_PCRE) ngx_regex_init(); #endif ngx_pid = ngx_getpid(); //init log,调用ngx_log_init()初始化日志,如初始化全局变量ngx_prefix,打开日志文件ngx_log_file.fd 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() */ //清零 ngx_memzero(&init_cycle, sizeof(ngx_cycle_t)); init_cycle.log = log; ngx_cycle = &init_cycle; //创建内存池 init_cycle.pool = ngx_create_pool(1024, log); if (init_cycle.pool == NULL) { return 1; } //命令行参数保存到ngx_os_argv、ngx_argc以及ngx_argv这几个全局的变量中。这算是一个备份存储,方便以后master进程做热代码替换之用 if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) { return 1; } //初始化ngx_cycle的prefix, conf_prefix, conf_file, conf_param等字段 if (ngx_process_options(&init_cycle) != NGX_OK) { return 1; } //调用ngx_os_init()初始化系统相关变量,如内存页面大小ngx_pagesize,ngx_cacheline_size,最大连接数ngx_max_sockets等; if (ngx_os_init(log) != NGX_OK) { return 1; } /* * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init() 调用ngx_crc32_table_init()初始化CRC表(后续的CRC校验通过查表进行,效率高) */ if (ngx_crc32_table_init() != NGX_OK) { return 1; } /* " 调用ngx_add_inherited_sockets()继承sockets; o 解析环境变量NGINX_VAR="NGINX"中的sockets,并保存至ngx_cycle.listening数组; o 设置ngx_inherited=1; o 调用ngx_set_inherited_sockets()逐一对ngx_cycle.listening数组中的sockets进行设置 */ if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) { return 1; } //初始化全局模块数组当中每个模块的index //这个神秘的数组却是在自动编译的时候生成的,位于objs/ngx_modules.c文件中。这个循环的目的是清晰可见的--对所有模块进行索引编号,方便以后访问 ngx_max_module = 0; for (i = 0; ngx_modules[i]; i++) { ngx_modules[i]->index = ngx_max_module++; } //o 该初始化主要对ngx_cycle结构进行,核心!! cycle = ngx_init_cycle(&init_cycle); if (cycle == NULL) { if (ngx_test_config) { ngx_log_stderr(0, "configuration file %s test failed", init_cycle.conf_file.data); } return 1; } if (ngx_test_config) { if (!ngx_quiet_mode) { ngx_log_stderr(0, "configuration file %s test is successful", cycle->conf_file.data); } return 0; } //" 若有信号,则进入ngx_signal_process()处理 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) //主要完成信号处理程序的注册 if (ngx_init_signals(cycle->log) != NGX_OK) { return 1; } //" 若无继承sockets,且设置了守护进程标识,则调用ngx_daemon()创建守护进程 if (!ngx_inherited && ccf->daemon) { if (ngx_daemon(cycle->log) != NGX_OK) { return 1; } ngx_daemonized = 1; } #endif //" 调用ngx_create_pidfile()创建进程记录文件 if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) { return 1; } //log file is OK if (cycle->log->file->fd != ngx_stderr) { if (ngx_set_stderr(cycle->log->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, ngx_set_stderr_n " failed"); 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; //进入进程主循环 if (ngx_process == NGX_PROCESS_SINGLE) { ngx_single_process_cycle(cycle); //单进程模式 } else { ngx_master_process_cycle(cycle); //master-slave模式这个过程里实现了master-worker模式的进程模型,也是生成环境下Nginx的常用模型 } return 0; }