incubator-nuttx/libs/libc/netdb/lib_dnsbind.c

107 lines
3.1 KiB
C

/****************************************************************************
* libs/libc/netdb/lib_dnsbind.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/time.h>
#include <unistd.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/net/dns.h>
#include "netdb/lib_dns.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef CONFIG_NET_SOCKOPTS
# error CONFIG_NET_SOCKOPTS required by this logic
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: dns_bind
*
* Description:
* Initialize the DNS resolver and return a socket bound to the DNS name
* server. The name server was previously selected via dns_server().
*
* Input Parameters:
* None
*
* Returned Value:
* On success, the bound, non-negative socket descriptor is returned. A
* negated errno value is returned on any failure.
*
****************************************************************************/
int dns_bind(sa_family_t family)
{
struct timeval tv;
int sd;
int ret;
/* Create a new socket */
sd = socket(family, SOCK_DGRAM | SOCK_CLOEXEC, 0);
if (sd < 0)
{
ret = -get_errno();
nerr("ERROR: socket() failed: %d\n", ret);
return ret;
}
/* Set up a receive timeout */
tv.tv_sec = CONFIG_NETDB_DNSCLIENT_RECV_TIMEOUT;
tv.tv_usec = 0;
ret = setsockopt(sd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(struct timeval));
if (ret >= 0)
{
/* Set up a send timeout */
tv.tv_sec = CONFIG_NETDB_DNSCLIENT_SEND_TIMEOUT;
tv.tv_usec = 0;
ret = setsockopt(sd, SOL_SOCKET, SO_SNDTIMEO, &tv,
sizeof(struct timeval));
}
if (ret < 0)
{
ret = -get_errno();
nerr("ERROR: setsockopt() failed: %d\n", ret);
close(sd);
return ret;
}
return sd;
}