resolver.h

来自「AMLOGIC DPF source code」· C头文件 代码 · 共 92 行

/*******************************************************************
 * 
 *  Copyright C 2005 by Amlogic, Inc. All Rights Reserved.
 *
 *  Description: 
 *
 *  Author: Amlogic Software
 *  Created: Fri Nov 11 00:51:49 2005
 *
 *******************************************************************/
/** @file
 */

#ifndef __LWIP_RESOLVER_H__
#define __LWIP_RESOLVER_H__

#include "lwip/opt.h"
#include "lwip/netif.h"
#include "lwip/udp.h"

/*
_define()
*/

/** DNS resolver return status */
#define RES_SUCCESS            0       /* DNS done */
/** DNS resolver return status */
#define RES_TIMEOUT            1       /* DNS failed due to timeout. */
/** DNS resolver return status */
#define RES_FAILED             3       /* Bad Domain Name. */
/** DNS resolver return status */
#define RES_FAMILY_ERR         4       /* unknown family type. */
/** DNS resolver return status */
#define RES_NAME_ERR           5       /* wrong domain name. */
/** DNS resolver return status */
#define RES_BUFF_ERR           6       /* query buffer alloc error */

typedef struct _resolver_s RESOLVER;

/**
 * Set the IP address for the DNS server.
 * @param addr DNS Server address
 */
void
dns_set_server(struct in_addr *primary, struct in_addr *secondary);

/**
 * Get the IP address for the DNS server.
 */
void
dns_get_server(struct in_addr *primary, struct in_addr *secondary);

/**
 * Clear the IP address for the DNS server.
 */
void
dns_clear_server(void);

/** 
 * callback function, return domain address in hostent structure pointer, 
 * be sure call res_free(res) at the end of callback function to free memory.
 *
 * @param arg User context used in callbacks.
 * @param status DNS resolver return status.
 * @param host_result A pointer to a hostent structure
 * @param res A pointer to a RESOLVER structure.
 *
 * @see gethostbyname_a(const char *name, int af, RES_CALLBACK callback, void *arg)
 * @see res_free(void *res)
 */
typedef void (*RES_CALLBACK)(void *arg, int status, struct hostent *host_result, void *res);

/** DNS server address */
extern struct ip_addr      res_DNS_addr;

/*
_function()
*/
/** Synchronous function, return domain address in hostent structure pointer*/
 struct hostent *gethostbyname (const char *name);
/** Asynchronous function, return domain address in callback function */
 RESOLVER *gethostbyname_a(const char *name, int af, RES_CALLBACK callback, void *arg);
/** remove RESOLVER descriptor.  Calling this function invalidates
 * any hostents returned. */
 void   res_free(void *res);
/** Create a hostent independent of a resolver context including
 * deep copies of the host name and the alias strings. */
extern struct hostent *
hostent_duplicate(struct hostent *hp);

#endif /*__LWIP_RESOLVER_H__*/