include builtins\cffi.e

constant AF_UNSPEC = 0,
--       AF_INET = 2,
--       AF_INET6 = 23,
--       SOCK_STREAM = 1,
         SOCK_DGRAM = 2,
--       IPPROTO_TCP = 6,
         NI_MAXHOST = 1025,
         NI_NUMERICHOST = iff(platform()=LINUX?1:2)

constant tWAD = """
typedef struct WSAData {
  WORD           wVersion;
  WORD           wHighVersion;
  char           szDescription[257];
  char           szSystemStatus[129];
  unsigned short iMaxSockets;
  unsigned short iMaxUdpDg;
  char           *lpVendorInfo;
} WSADATA, *LPWSADATA;
""",
tWAS = """
int WSAStartup(
  _In_   WORD wVersionRequested,
  _Out_  LPWSADATA lpWSAData
);
""",
tWAC = """
int WSACleanup(void);
""",
tAI_W="""
typedef struct addrinfo {
  int             ai_flags;
  int             ai_family;
  int             ai_socktype;
  int             ai_protocol;
  size_t          ai_addrlen;
  char            *ai_canonname;
  struct sockaddr  *ai_addr;
  struct addrinfo  *ai_next;
} ADDRINFOA, *PADDRINFOA;
""",
tAI_L="""
typedef struct addrinfo {
    int              ai_flags;
    int              ai_family;
    int              ai_socktype;
    int              ai_protocol;
    int              ai_addrlen;
    struct sockaddr *ai_addr;
    char            *ai_canonname;
    struct addrinfo *ai_next;
};
""",
tGAI = """
int getaddrinfo(
  _In_opt_  PCSTR pNodeName,
  _In_opt_  PCSTR pServiceName,
  _In_opt_  const ADDRINFOA *pHints,
  _Out_     PADDRINFOA *ppResult
);
""",
--int getaddrinfo(const char *node, const char *service,
--                     const struct addrinfo *hints,
--                     struct addrinfo **res);
tGNI = """
int getnameinfo(
  _In_   sockaddr *sa,
  _In_   int salen,
  _Out_  char *host,
  _In_   DWORD hostlen,
  _Out_  char *serv,
  _In_   DWORD servlen,
  _In_   int flags
);
""",
--int getnameinfo(const struct sockaddr *addr, socklen_t addrlen,
--                     char *host, socklen_t hostlen,
--                     char *serv, socklen_t servlen, int flags);
tFAI = """
void freeaddrinfo(
  _In_  struct addrinfo *ai
);
"""
--void freeaddrinfo(struct addrinfo *res);

integer xgetaddrinfo = NULL, xgetnameinfo, xfreeaddrinfo, idAI,
        xwsastartup, xwsacleanup, error

function get_name_info(string fqdn)
    if xgetaddrinfo=NULL then
        atom lib
        if platform()=WINDOWS then
            integer idWAD = define_struct(tWAD)
            atom pWAD = allocate_struct(idWAD,cleanup:=true)
            lib = open_dll("Ws2_32.dll")
            xwsastartup = define_cffi_func(lib,tWAS)
            xwsacleanup = define_cffi_func(lib,tWAC)
            error = c_func(xwsastartup,{#00020002,pWAD})
            if error then ?9/0 end if
            idAI = define_struct(tAI_W)
        elsif platform()=LINUX then
            lib = open_dll("libc.so.6")
            idAI = define_struct(tAI_L)
        end if
        xgetaddrinfo = define_cffi_func(lib,tGAI)
        xgetnameinfo = define_cffi_func(lib,tGNI)
        xfreeaddrinfo = define_cffi_proc(lib,tFAI)
    end if
    atom hints = allocate_struct(idAI,cleanup:=true),
         res = allocate(machine_word(),cleanup:=true),
         host = allocate(NI_MAXHOST,cleanup:=true)
    set_struct_field(idAI,hints,"ai_family",AF_UNSPEC)
--  set_struct_field(idAI,hints,"ai_socktype",SOCK_STREAM)
    set_struct_field(idAI,hints,"ai_socktype",SOCK_DGRAM)
    error = c_func(xgetaddrinfo,{fqdn,NULL,hints,res})
    if error then ?9/0 end if
    res = peekNS(res,machine_word(),false)
    atom ptr = res
    sequence results = {}
    while ptr!=NULL do
        atom addr = get_struct_field(idAI,ptr,"ai_addr")
        integer len = get_struct_field(idAI,ptr,"ai_addrlen")
        error = c_func(xgetnameinfo,{addr, len, host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST})
        if error then ?9/0 end if
        results = append(results,peek_string(host))
        ptr = get_struct_field(idAI,ptr,"ai_next")
    end while
    c_proc(xfreeaddrinfo,{res})
    return results
end function

procedure WSACleanup()
    if platform()=WINDOWS then
        error = c_func(xwsacleanup,{})
        if error then crash("WSACleanup failed: %d\n",{error}) end if
    end if
end procedure

?get_name_info("www.kame.net")
WSACleanup()