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
  #if ESP_LWIP
  #if LWIP_COMPAT_SOCKET_ADDR == 1
  /* Some libraries have problems with inet_... being macros, so please use this define 
     to declare normal functions */
  static inline int gethostbyname_r(const char *name, struct hostent *ret, char *buf, size_t buflen, struct hostent **result, int *h_errnop)
  { return lwip_gethostbyname_r(name, ret, buf, buflen, result, h_errnop); }
  static inline struct hostent *gethostbyname(const char *name)
  { return lwip_gethostbyname(name); }
  static inline void freeaddrinfo(struct addrinfo *ai)
  { lwip_freeaddrinfo(ai); }
  static inline int getaddrinfo(const char *nodename, const char *servname, const struct addrinfo *hints, struct addrinfo **res)
  { return lwip_getaddrinfo(nodename, servname, hints, res); }
  #else
  /* By default fall back to original inet_... macros */
  
  /** @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_SOCKET_ADDR == 1 */
  
  #else /* ESP_LWIP */
  
  /** @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 /* ESP_LWIP */
  #endif /* LWIP_COMPAT_SOCKETS */
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* LWIP_DNS && LWIP_SOCKET */
  
  #endif /* LWIP_HDR_NETDB_H */
  