/* * Redistribution and use in source and binary forms, with or without modification,  * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, *    this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright notice, *    this list of conditions and the following disclaimer in the documentation *    and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products *    derived from this software without specific prior written permission.  * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY  * OF SUCH DAMAGE. * * This file is part of the lwIP TCP/IP stack. *  * Author: Simon Goldschmidt * */#include "lwip/opt.h"#if LWIP_DNS && LWIP_SOCKET#include "lwip/sockets.h"/* some rarely used options */#ifndef LWIP_DNS_API_DECLARE_H_ERRNO#define LWIP_DNS_API_DECLARE_H_ERRNO 1#endif#ifndef LWIP_DNS_API_DEFINE_ERRORS#define LWIP_DNS_API_DEFINE_ERRORS 1#endif#ifndef LWIP_DNS_API_DECLARE_STRUCTS#define LWIP_DNS_API_DECLARE_STRUCTS 1#endif#if LWIP_DNS_API_DEFINE_ERRORS/** Errors used by the DNS API functions, h_errno can be one of them */#define EAI_NONAME      200#define EAI_SERVICE     201#define EAI_FAIL        202#define EAI_MEMORY      203#define HOST_NOT_FOUND  210#define NO_DATA         211#define NO_RECOVERY     212#define TRY_AGAIN       213#endif /* LWIP_DNS_API_DEFINE_ERRORS */#if LWIP_DNS_API_DECLARE_STRUCTSstruct hostent {    char  *h_name;      /* Official name of the host. */    char **h_aliases;   /* A pointer to an array of pointers to alternative host names,                           terminated by a null pointer. */    int    h_addrtype;  /* Address type. */    int    h_length;    /* The length, in bytes, of the address. */    char **h_addr_list; /* A pointer to an array of pointers to network addresses (in                           network byte order) for the host, terminated by a null pointer. */#define h_addr h_addr_list[0] /* for backward compatibility */};struct addrinfo {    int               ai_flags;      /* Input flags. */    int               ai_family;     /* Address family of socket. */    int               ai_socktype;   /* Socket type. */    int               ai_protocol;   /* Protocol of socket. */    socklen_t         ai_addrlen;    /* Length of socket address. */    struct sockaddr  *ai_addr;       /* Socket address of socket. */    char             *ai_canonname;  /* Canonical name of service location. */    struct addrinfo  *ai_next;       /* Pointer to next in list. */};#endif /* LWIP_DNS_API_DECLARE_STRUCTS */#if LWIP_DNS_API_DECLARE_H_ERRNO/* application accessable error code set by the DNS API functions */extern int h_errno;#endif /* LWIP_DNS_API_DECLARE_H_ERRNO*/struct hostent *lwip_gethostbyname(const char *name);int lwip_gethostbyname_r(const char *name, struct hostent *ret, char *buf,                size_t buflen, struct hostent **result, int *h_errnop);void lwip_freeaddrinfo(struct addrinfo *ai);int lwip_getaddrinfo(const char *nodename,       const char *servname,       const struct addrinfo *hints,       struct addrinfo **res);#if LWIP_COMPAT_SOCKETS#define gethostbyname(name) lwip_gethostbyname(name)#define gethostbyname_r(name, ret, buf, buflen, result, h_errnop) \       lwip_gethostbyname_r(name, ret, buf, buflen, result, h_errnop)#define freeaddrinfo(addrinfo) lwip_freeaddrinfo(a)#define getaddrinfo(nodname, servname, hints, res) \       lwip_getaddrinfo(nodname, servname, hints, res)#endif /* LWIP_COMPAT_SOCKETS */#endif /* LWIP_DNS && LWIP_SOCKET */