text: /**
   * @file
   * NETDB API (sockets)
   */
  
  /*
   * 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
   *
   */
  #ifndef LWIP_HDR_NETDB_H
  #define LWIP_HDR_NETDB_H
  
  #include "lwip/opt.h"
  
  #if LWIP_DNS && LWIP_SOCKET
  
  #include "lwip/arch.h"
  #include "lwip/inet.h"
  #include "lwip/sockets.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /* 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_DEFINE_FLAGS
  #define LWIP_DNS_API_DEFINE_FLAGS 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 EAI_FAMILY 204
  
  #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_DEFINE_FLAGS
  /* input flags for struct addrinfo */
  #define AI_PASSIVE 0x01
  #define AI_CANONNAME 0x02
  #define AI_NUMERICHOST 0x04
  #define AI_NUMERICSERV 0x08
  #define AI_V4MAPPED 0x10
  #define AI_ALL 0x20
  #define AI_ADDRCONFIG 0x40
  #endif /* LWIP_DNS_API_DEFINE_FLAGS */
  
  #if LWIP_DNS_API_DECLARE_STRUCTS
  struct 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 */
  
  #define NETDB_ELEM_SIZE                                                        \
    (sizeof(struct addrinfo) + sizeof(struct sockaddr_storage) +                 \
     DNS_MAX_NAME_LENGTH + 1)
  
  #if LWIP_DNS_API_DECLARE_H_ERRNO
  /* application accessible 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
  /** @ingroup netdbapi */
  #define gethostbyname(name) lwip_gethostbyname(name)
  /** @ingroup netdbapi */
  #define gethostbyname_r(name, ret, buf, buflen, result, h_errnop)              \
    lwip_gethostbyname_r(name, ret, buf, buflen, result, h_errnop)
  /** @ingroup netdbapi */
  #define freeaddrinfo(addrinfo) lwip_freeaddrinfo(addrinfo)
  /** @ingroup netdbapi */
  #define getaddrinfo(nodname, servname, hints, res)                             \
    lwip_getaddrinfo(nodname, servname, hints, res)
  #endif /* LWIP_COMPAT_SOCKETS */
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* LWIP_DNS && LWIP_SOCKET */
  
  #endif /* LWIP_HDR_NETDB_H */
  