//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;
}
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;
}
/*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;
}