static ngx_listening_t *
ngx_http_add_listening(ngx_conf_t *cf, ngx_http_conf_addr_t *addr)
{
ngx_listening_t *ls;
ngx_http_core_loc_conf_t *clcf;
ngx_http_core_srv_conf_t *cscf;
ls = ngx_create_listening(cf, &addr-;>opt.u.sockaddr, addr->opt.socklen);
if (ls == NULL) {
return NULL;
}
ls->addr_ntop = 1;
ls->handler = ngx_http_init_connection;
cscf = addr->default_server;
ls->pool_size = cscf->connection_pool_size;
ls->post_accept_timeout = cscf->client_header_timeout;
clcf = cscf->ctx->loc_conf[ngx_http_core_module.ctx_index];
ls->logp = clcf->error_log;
ls->log.data = &ls-;>addr_text;
ls->log.handler = ngx_accept_log_error;
ls->backlog = addr->opt.backlog;
ls->rcvbuf = addr->opt.rcvbuf;
ls->sndbuf = addr->opt.sndbuf;
ls->keepalive = addr->opt.so_keepalive;
return ls;
}
ngx_listening_t *
ngx_create_listening(ngx_conf_t *cf, void *sockaddr, socklen_t socklen)
{
size_t len;
ngx_listening_t *ls;
struct sockaddr *sa;
u_char text[NGX_SOCKADDR_STRLEN];
ls = ngx_array_push(&cf-;>cycle->listening);
if (ls == NULL) {
return NULL;
}
ngx_memzero(ls, sizeof(ngx_listening_t));
sa = ngx_palloc(cf->pool, socklen);
if (sa == NULL) {
return NULL;
}
ngx_memcpy(sa, sockaddr, socklen);
ls->sockaddr = sa;
ls->socklen = socklen;
len = ngx_sock_ntop(sa, socklen, text, NGX_SOCKADDR_STRLEN, 1);
ls->addr_text.len = len;
switch (ls->sockaddr->sa_family) {
case AF_INET:
ls->addr_text_max_len = NGX_INET_ADDRSTRLEN;
break;
default:
ls->addr_text_max_len = NGX_SOCKADDR_STRLEN;
break;
}
ls->addr_text.data = ngx_pnalloc(cf->pool, len);
if (ls->addr_text.data == NULL) {
return NULL;
}
ngx_memcpy(ls->addr_text.data, text, len);
ls->fd = (ngx_socket_t) -1;
ls->type = SOCK_STREAM;
ls->backlog = NGX_LISTEN_BACKLOG; //511
ls->rcvbuf = -1;
ls->sndbuf = -1;
return ls;
}
static ngx_int_t
ngx_http_add_addrs(ngx_conf_t *cf, ngx_http_port_t *hport,
ngx_http_conf_addr_t *addr)
{
ngx_uint_t i;
ngx_http_in_addr_t *addrs;
struct sockaddr_in *sin;
ngx_http_virtual_names_t *vn;
hport->addrs = ngx_pcalloc(cf->pool,
hport->naddrs * sizeof(ngx_http_in_addr_t));
if (hport->addrs == NULL) {
return NGX_ERROR;
}
addrs = hport->addrs;
for (i = 0; i < hport->naddrs; i++) {
sin = &addr;[i].opt.u.sockaddr_in;
addrs[i].addr = sin->sin_addr.s_addr;
addrs[i].conf.default_server = addr[i].default_server;
#if (NGX_HTTP_SSL)
addrs[i].conf.ssl = addr[i].opt.ssl;
#endif
#if (NGX_HTTP_SPDY)
addrs[i].conf.spdy = addr[i].opt.spdy;
#endif
addrs[i].conf.proxy_protocol = addr[i].opt.proxy_protocol;
if (addr[i].hash.buckets == NULL
&& (addr[i].wc_head == NULL
|| addr[i].wc_head->hash.buckets == NULL)
&& (addr[i].wc_tail == NULL
|| addr[i].wc_tail->hash.buckets == NULL)
#if (NGX_PCRE)
&& addr[i].nregex == 0
#endif
)
{
continue;
}
vn = ngx_palloc(cf->pool, sizeof(ngx_http_virtual_names_t));
if (vn == NULL) {
return NGX_ERROR;
}
addrs[i].conf.virtual_names = vn;
vn->names.hash = addr[i].hash;
vn->names.wc_head = addr[i].wc_head;
vn->names.wc_tail = addr[i].wc_tail;
#if (NGX_PCRE)
vn->nregex = addr[i].nregex;
vn->regex = addr[i].regex;
#endif
}
return NGX_OK;
}
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;
}
//地址相同
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; //当remain=1时，old_cycle不需要close fd()
if (ls[i].backlog != nls[n].backlog) {
nls[n].listen = 1; //backlog不同的时候，会在configure_listening_sockets中重新listen(fd, backlog)
}
break;
}
}
if (nls[n].fd == (ngx_socket_t) -1) {
nls[n].open = 1;
}
}
} else {
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
ls[i].open = 1;
}
}
if (ngx_open_listening_sockets(cycle) != NGX_OK) {
goto failed;
}
….
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);
}
}
ngx_int_t
ngx_open_listening_sockets(ngx_cycle_t *cycle)
{
int reuseaddr;
ngx_uint_t i, tries, failed;
ngx_err_t err;
ngx_log_t *log;
ngx_socket_t s;
ngx_listening_t *ls;
reuseaddr = 1;
#if (NGX_SUPPRESS_WARN)
failed = 0;
#endif
log = cycle->log;
/* TODO: configurable try number */
for (tries = 5; tries; tries--) {
failed = 0;
/* for each listening socket */
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
if (ls[i].ignore) { //和inherited_sockets有关
continue;
}
if (ls[i].fd != (ngx_socket_t) -1) {
continue;
}
if (ls[i].inherited) {
continue;
}
s = ngx_socket(ls[i].sockaddr->sa_family, ls[i].type, 0);
if (s == (ngx_socket_t) -1) {
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
ngx_socket_n " %V failed", &ls;[i].addr_text);
return NGX_ERROR;
}
if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
(const void *) &reuseaddr;, sizeof(int))
== -1)
{
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
"setsockopt(SO_REUSEADDR) %V failed",
&ls;[i].addr_text);
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
ngx_close_socket_n " %V failed",
&ls;[i].addr_text);
}
return NGX_ERROR;
}
if (!(ngx_event_flags & NGX_USE_AIO_EVENT)) {
if (ngx_nonblocking(s) == -1) {
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
ngx_nonblocking_n " %V failed",
&ls;[i].addr_text);
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
ngx_close_socket_n " %V failed",
&ls;[i].addr_text);
}
return NGX_ERROR;
}
}
if (bind(s, ls[i].sockaddr, ls[i].socklen) == -1) {
err = ngx_socket_errno;
if (err == NGX_EADDRINUSE && ngx_test_config) {
continue;
}
ngx_log_error(NGX_LOG_EMERG, log, err,
"bind() to %V failed", &ls;[i].addr_text);
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
ngx_close_socket_n " %V failed",
&ls;[i].addr_text);
}
if (err != NGX_EADDRINUSE) {
return NGX_ERROR;
}
failed = 1;
continue;
}
//如listen 80和listen 1.1.1.1:80 共用一个listening，即共用一个backlog
if (listen(s, ls[i].backlog) == -1) {
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
"listen() to %V, backlog %d failed",
&ls;[i].addr_text, ls[i].backlog);
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_EMERG, log, ngx_socket_errno,
ngx_close_socket_n " %V failed",
&ls;[i].addr_text);
}
return NGX_ERROR;
}
ls[i].listen = 1;
ls[i].fd = s;
}
if (!failed) {
break;
}
/* TODO: delay configurable */
ngx_log_error(NGX_LOG_NOTICE, log, 0,
"try again to bind() after 500ms");
ngx_msleep(500);
}
if (failed) {
ngx_log_error(NGX_LOG_EMERG, log, 0, "still could not bind()");
return NGX_ERROR;
}
return NGX_OK;
}
void
ngx_configure_listening_sockets(ngx_cycle_t *cycle)
{
int value;
ngx_uint_t i;
ngx_listening_t *ls;
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
ls[i].log = *ls[i].logp;
。。。
if (ls[i].keepalive) {
value = (ls[i].keepalive == 1) ? 1 : 0;
if (setsockopt(ls[i].fd, SOL_SOCKET, SO_KEEPALIVE,
(const void *) &value;, sizeof(int))
== -1)
{
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_socket_errno,
"setsockopt(SO_KEEPALIVE, %d) %V failed, ignored",
value, &ls;[i].addr_text);
}
}
if (ls[i].listen) {
/* change backlog via listen() */
if (listen(ls[i].fd, ls[i].backlog) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_socket_errno,
"listen() to %V, backlog %d failed, ignored",
&ls;[i].addr_text, ls[i].backlog);
}
}
}
return;
}
函数功能：ngx_event_accept后的ls->handler= ngx_http_init_connection。
void
ngx_http_init_connection(ngx_connection_t *c)
{
ngx_uint_t i;
ngx_event_t *rev;
struct sockaddr_in *sin;
ngx_http_port_t *port;
ngx_http_in_addr_t *addr;
ngx_http_log_ctx_t *ctx;
ngx_http_connection_t *hc;
hc = ngx_pcalloc(c->pool, sizeof(ngx_http_connection_t));
if (hc == NULL) {
ngx_http_close_connection(c);
return;
}
c->data = hc;
/* find the server configuration for the address:port */
port = c->listening->servers; /*ngx_http_port_t */
if (port->naddrs > 1) {
if (ngx_connection_local_sockaddr(c, NULL, 0) != NGX_OK) {
ngx_http_close_connection(c);
return;
}
switch (c->local_sockaddr->sa_family) {
default: /* AF_INET */
sin = (struct sockaddr_in *) c->local_sockaddr; //here
addr = port->addrs;
for (i = 0; i < port->naddrs - 1; i++) {
if (addr[i].addr == sin->sin_addr.s_addr) {
break;
}
}
hc->addr_conf = &addr;[i].conf;
break;
}
} else {
switch (c->local_sockaddr->sa_family) {
default: /* AF_INET */
addr = port->addrs;
hc->addr_conf = &addr;[0].conf;
break;
}
}
…
rev = c->read;
rev->handler = ngx_http_wait_request_handler; //普通request_handler
c->write->handler = ngx_http_empty_handler;
#if (NGX_HTTP_SPDY)
if (hc->addr_conf->spdy) {
rev->handler = ngx_http_spdy_init; //spdy request_handler
}
#endif
…
if (rev->ready) {
/* the deferred accept(), rtsig, aio, iocp */
if (ngx_use_accept_mutex) {
ngx_post_event(rev, &ngx;_posted_events);
return;
}
rev->handler(rev);
return;
}
ngx_add_timer(rev, c->listening->post_accept_timeout);
ngx_reusable_connection(c, 1);
if (ngx_handle_read_event(rev, 0) != NGX_OK) {
ngx_http_close_connection(c);
return;
}
}
http://www.cnblogs.com/chengxuyuancc/p/3789216.html
SLB 7层负载均衡“HUNG”问题追查：