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;
}
