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/*
* Copyright (C) Igor Sysoev
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
typedef struct {
ngx_connection_t *connection;
struct sockaddr *sockaddr;
socklen_t socklen;
ngx_str_r server;
ngx_str_r name;
ngx_event_handler_pt handler;
ngx_log_t *pool;
ngx_log_t *log;
} ngx_resolver_t;
ngx_int_t
ngx_gethostbyname(ngx_resolver_t *r)
{
ngx_socket_t s;
if (r->connection) {
return NGX_OK;
}
s = ngx_socket(AF_INET, SOCK_DGRAM, 0);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, r->log, 0, "socket %d", s);
if (s == -1) {
ngx_log_error(NGX_LOG_ALERT, r->log, ngx_socket_errno,
ngx_socket_n " failed");
return NGX_ERROR;
}
c = ngx_get_connection(s, r->log);
if (c == NULL) {
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, r->log, ngx_socket_errno,
ngx_close_socket_n "failed");
}
return NGX_ERROR;
}
rev = c->read;
wev = c->write;
rev->log = pc->log;
wev->log = pc->log;
r->connection = c;
/*
* TODO: MT: - ngx_atomic_fetch_add()
* or protection by critical section or mutex
*
* TODO: MP: - allocated in a shared memory
* - ngx_atomic_fetch_add()
* or protection by critical section or mutex
*/
c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
#if (NGX_THREADS)
rev->lock = pc->lock;
wev->lock = pc->lock;
rev->own_lock = &c->lock;
wev->own_lock = &c->lock;
#endif
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, pc->log, 0,
"connect to %V, fd:%d #%d", &r->server, s, c->number);
rc = connect(s, r->sockaddr, r->socklen);
if (rc == -1) {
ngx_log_error(level, r->log, ngx_socket_errno,
"connect() to %V failed", &r->server);
return NGX_ERROR;
}
if (ngx_add_conn) {
if (ngx_add_conn(c) == NGX_ERROR) {
return NGX_ERROR;
}
}
if (ngx_add_conn) {
if (rc == -1) {
/* NGX_EINPROGRESS */
return NGX_AGAIN;
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected");
wev->ready = 1;
return NGX_OK;
}
if (ngx_event_flags & NGX_USE_AIO_EVENT) {
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, pc->log, ngx_socket_errno,
"connect(): %d", rc);
/* aio, iocp */
if (ngx_blocking(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_blocking_n " failed");
return NGX_ERROR;
}
/*
* FreeBSD's aio allows to post an operation on non-connected socket.
* NT does not support it.
*
* TODO: check in Win32, etc. As workaround we can use NGX_ONESHOT_EVENT
*/
rev->ready = 1;
wev->ready = 1;
return NGX_OK;
}
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
/* kqueue */
event = NGX_CLEAR_EVENT;
} else {
/* select, poll, /dev/poll */
event = NGX_LEVEL_EVENT;
}
if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) {
return NGX_ERROR;
}
if (rc == -1) {
/* NGX_EINPROGRESS */
if (ngx_add_event(wev, NGX_WRITE_EVENT, event) != NGX_OK) {
return NGX_ERROR;
}
return NGX_AGAIN;
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected");
wev->ready = 1;
return NGX_OK;
}
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