glibc/resolv/netdb.h

/* Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it
   and/or modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be
   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If
   not, write to the Free Software Foundation, Inc., 59 Temple Place -
   Suite 330, Boston, MA 02111-1307, USA.  */

/* All data returned by the network data base library are supplied in
   host order and returned in network order (suitable for use in
   system calls).  */

#ifndef	_NETDB_H
#define	_NETDB_H	1

#include <features.h>

/* This is necessary to make this include file properly replace the
   Sun version.  */
#include <rpc/netdb.h>
#include <sys/socket.h>		/* need socklen_t */
#define __need_size_t
#include <stddef.h>

/* Absolute file name for network data base files.  */
#define	_PATH_HEQUIV		"/etc/hosts.equiv"
#define	_PATH_HOSTS		"/etc/hosts"
#define	_PATH_NETWORKS		"/etc/networks"
#define	_PATH_NSSWITCH_CONF	"/etc/nsswitch.conf"
#define	_PATH_PROTOCOLS		"/etc/protocols"
#define	_PATH_SERVICES		"/etc/services"


__BEGIN_DECLS

/* Error status for non-reentrant lookup functions.  */
extern int h_errno;

/* Function to get address of global `h_errno' variable.  */
extern int *__h_errno_location __P ((void)) __attribute__ ((__const__));

#ifdef _LIBC
# ifdef _LIBC_REENTRANT
static inline int
__set_h_errno (int __err)
{
  return *__h_errno_location () = __err;
}
# else
#  define __set_h_errno(x) (h_errno = (x))
# endif	/* _LIBC_REENTRANT */
#endif /* _LIBC */


#if !defined _LIBC || defined _LIBC_REENTRANT
/* Use a macro to access always the thread specific `h_errno' variable.  */
# define h_errno (*__h_errno_location ())
#endif


/* Possible values left in `h_errno'.  */
#define	NETDB_INTERNAL	-1	/* See errno.  */
#define	NETDB_SUCCESS	0	/* No problem.  */
#define	HOST_NOT_FOUND	1	/* Authoritative Answer Host not found.  */
#define	TRY_AGAIN	2	/* Non-Authoritative Host not found,
				   or SERVERFAIL.  */
#define	NO_RECOVERY	3	/* Non recoverable errors, FORMERR, REFUSED,
				   NOTIMP.  */
#define	NO_DATA		4	/* Valid name, no data record of requested
				   type.  */
#define	NO_ADDRESS	NO_DATA	/* No address, look for MX record.  */

/* Print error indicated by `h_errno' variable on standard error.  STR
   if non-null is printed before the error string.  */
extern void herror __P ((__const char *__str));

/* Return string associated with error ERR_NUM.  */
extern __const char *hstrerror __P ((int __err_num));



/* Description of data base entry for a single host.  */
struct hostent
{
  char *h_name;			/* Official name of host.  */
  char **h_aliases;		/* Alias list.  */
  int h_addrtype;		/* Host address type.  */
  int h_length;			/* Length of address.  */
  char **h_addr_list;		/* List of addresses from name server.  */
#define	h_addr	h_addr_list[0]	/* Address, for backward compatibility.  */
};

/* Open host data base files and mark them as staying open even after
   a later search if STAY_OPEN is non-zero.  */
extern void sethostent __P ((int __stay_open));

/* Close host data base files and clear `stay open' flag.  */
extern void endhostent __P ((void));

/* Get next entry from host data base file.  Open data base if
   necessary.  */
extern struct hostent *gethostent __P ((void));

/* Return entry from host data base which address match ADDR with
   length LEN and type TYPE.  */
extern struct hostent *gethostbyaddr __P ((__const char *__addr, size_t __len,
					   int __type));

/* Return entry from host data base for host with NAME.  */
extern struct hostent *gethostbyname __P ((__const char *__name));

/* Return entry from host data base for host with NAME.  AF must be
   set to the address type which is `AF_INET' for IPv4 or `AF_INET6'
   for IPv6.  */
extern struct hostent *gethostbyname2 __P ((__const char *__name, int __af));

#ifdef	__USE_MISC
/* Reentrant versions of the functions above.  The additional
   arguments specify a buffer of BUFLEN starting at BUF.  The last
   argument is a pointer to a variable which gets the value which
   would be stored in the global variable `herrno' by the
   non-reentrant functions.  */
extern int gethostent_r __P ((struct hostent *__restrict __result_buf,
			      char *__restrict __buf, size_t __buflen,
			      struct hostent **__restrict __result,
			      int *__restrict __h_errnop));

extern int gethostbyaddr_r __P ((__const char *__restrict __addr, size_t __len,
				 int __type,
				 struct hostent *__restrict __result_buf,
				 char *__restrict __buf, size_t __buflen,
				 struct hostent **__restrict __result,
				 int *__restrict __h_errnop));

extern int gethostbyname_r __P ((__const char *__restrict __name,
				 struct hostent *__restrict __result_buf,
				 char *__restrict __buf, size_t __buflen,
				 struct hostent **__restrict __result,
				 int *__restrict __h_errnop));

extern int gethostbyname2_r __P ((__const char *__restrict __name, int __af,
				  struct hostent *__restrict __result_buf,
				  char *__restrict __buf, size_t __buflen,
				  struct hostent **__restrict __result,
				  int *__restrict __h_errnop));
#endif	/* misc */


/* Return entry from host data base for host with NAME.  AF must be
   set to the desired address type (either `AF_INET' or `AF_INET6').
   FLAGS is some combination of the following AI_* values.  */
extern struct hostent *getnodebyname __P ((__const char *__name, int __af,
					   int __flags));

#define AI_V4MAPPED	1	/* IPv4-mapped addresses are acceptable.  */
#define AI_ALL		2	/* Return both IPv4 and IPv6 addresses.  */
#define AI_ADDRCONFIG	4	/* Use configuration of this host to choose
				   returned address type.  */
#define AI_DEFAULT	(AI_V4MAPPED | AI_ADDRCONFIG)


/* Description of data base entry for a single network.  NOTE: here a
   poor assumption is made.  The network number is expected to fit
   into an unsigned long int variable.  */
struct netent
{
  char *n_name;			/* Official name of network.  */
  char **n_aliases;		/* Alias list.  */
  int n_addrtype;		/* Net address type.  */
  unsigned long	int n_net;	/* Network number.  */
};

/* Open network data base files and mark them as staying open even
   after a later search if STAY_OPEN is non-zero.  */
extern void setnetent __P ((int __stay_open));

/* Close network data base files and clear `stay open' flag.  */
extern void endnetent __P ((void));

/* Get next entry from network data base file.  Open data base if
   necessary.  */
extern struct netent *getnetent __P ((void));

/* Return entry from network data base which address match NET and
   type TYPE.  */
extern struct netent *getnetbyaddr __P ((unsigned long int __net,
					 int __type));

/* Return entry from network data base for network with NAME.  */
extern struct netent *getnetbyname __P ((__const char *__name));

#ifdef	__USE_MISC
/* Reentrant versions of the functions above.  The additional
   arguments specify a buffer of BUFLEN starting at BUF.  The last
   argument is a pointer to a variable which gets the value which
   would be stored in the global variable `herrno' by the
   non-reentrant functions.  */
extern int getnetent_r __P ((struct netent *__restrict __result_buf,
			     char *__restrict __buf, size_t __buflen,
			     struct netent **__restrict __result,
			     int *__restrict __h_errnop));

extern int getnetbyaddr_r __P ((unsigned long int __net, int __type,
				struct netent *__restrict __result_buf,
				char *__restrict __buf, size_t __buflen,
				struct netent **__restrict __result,
				int *__restrict __h_errnop));

extern int getnetbyname_r __P ((__const char *__restrict __name,
				struct netent *__restrict __result_buf,
				char *__restrict __buf, size_t __buflen,
				struct netent **__restrict __result,
				int *__restrict __h_errnop));
#endif	/* misc */


/* Description of data base entry for a single service.  */
struct servent
{
  char *s_name;			/* Official service name.  */
  char **s_aliases;		/* Alias list.  */
  int s_port;			/* Port number.  */
  char *s_proto;		/* Protocol to use.  */
};

/* Open service data base files and mark them as staying open even
   after a later search if STAY_OPEN is non-zero.  */
extern void setservent __P ((int __stay_open));

/* Close service data base files and clear `stay open' flag.  */
extern void endservent __P ((void));

/* Get next entry from service data base file.  Open data base if
   necessary.  */
extern struct servent *getservent __P ((void));

/* Return entry from network data base for network with NAME and
   protocol PROTO.  */
extern struct servent *getservbyname __P ((__const char *__name,
					   __const char *__proto));

/* Return entry from service data base which matches port PORT and
   protocol PROTO.  */
extern struct servent *getservbyport __P ((int __port, __const char *__proto));


#ifdef	__USE_MISC
/* Reentrant versions of the functions above.  The additional
   arguments specify a buffer of BUFLEN starting at BUF.  */
extern int getservent_r __P ((struct servent *__restrict __result_buf,
			      char *__restrict __buf, size_t __buflen,
			      struct servent **__restrict __result));

extern int getservbyname_r __P ((__const char *__restrict __name,
				 __const char *__restrict __proto,
				 struct servent *__restrict __result_buf,
				 char *__restrict __buf, size_t __buflen,
				 struct servent **__restrict __result));

extern int getservbyport_r __P ((int __port, __const char *__restrict __proto,
				 struct servent *__restrict __result_buf,
				 char *__restrict __buf, size_t __buflen,
				 struct servent **__restrict __result));
#endif	/* misc */


/* Description of data base entry for a single service.  */
struct protoent
{
  char *p_name;			/* Official protocol name.  */
  char **p_aliases;		/* Alias list.  */
  int p_proto;			/* Protocol number.  */
};

/* Open protocol data base files and mark them as staying open even
   after a later search if STAY_OPEN is non-zero.  */
extern void setprotoent __P ((int __stay_open));

/* Close protocol data base files and clear `stay open' flag.  */
extern void endprotoent __P ((void));

/* Get next entry from protocol data base file.  Open data base if
   necessary.  */
extern struct protoent *getprotoent __P ((void));

/* Return entry from protocol data base for network with NAME.  */
extern struct protoent *getprotobyname __P ((__const char *__name));

/* Return entry from protocol data base which number is PROTO.  */
extern struct protoent *getprotobynumber __P ((int __proto));


#ifdef	__USE_MISC
/* Reentrant versions of the functions above.  The additional
   arguments specify a buffer of BUFLEN starting at BUF.  */
extern int getprotoent_r __P ((struct protoent *__restrict __result_buf,
			       char *__restrict __buf, size_t __buflen,
			       struct protoent **__restrict __result));

extern int getprotobyname_r __P ((__const char *__restrict __name,
				  struct protoent *__restrict __result_buf,
				  char *__restrict __buf, size_t __buflen,
				  struct protoent **__restrict __result));

extern int getprotobynumber_r __P ((int __proto,
				    struct protoent *__restrict __result_buf,
				    char *__restrict __buf, size_t __buflen,
				    struct protoent **__restrict __result));
#endif	/* misc */


/* Establish network group NETGROUP for enumeration.  */
extern int setnetgrent __P ((__const char *__netgroup));

/* Free all space allocated by previous `setnetgrent' call.  */
extern void endnetgrent __P ((void));

/* Get next member of netgroup established by last `setnetgrent' call
   and return pointers to elements in HOSTP, USERP, and DOMAINP.  */
extern int getnetgrent __P ((char **__restrict __hostp,
			     char **__restrict __userp,
			     char **__restrict __domainp));

/* Test whether NETGROUP contains the triple (HOST,USER,DOMAIN).  */
extern int innetgr __P ((__const char *__netgroup, __const char *__host,
			 __const char *__user, __const char *domain));

#ifdef	__USE_MISC
/* Reentrant version of `getnetgrent' where result is placed in BUFFER.  */
extern int getnetgrent_r __P ((char **__restrict __hostp,
			       char **__restrict __userp,
			       char **__restrict __domainp,
			       char *__restrict __buffer, size_t __buflen));
#endif	/* misc */


#ifdef __USE_BSD
/* Call `rshd' at port RPORT on remote machine *AHOST to execute CMD.
   The local user is LOCUSER, on the remote machine the command is
   executed as REMUSER.  In *FD2P the descriptor to the socket for the
   connection is returned.  The caller must have the right to use a
   reserved port.  When the function returns *AHOST contains the
   official host name.  */
extern int rcmd __P ((char **__restrict __ahost, unsigned short int __rport,
		      __const char *__restrict __locuser,
		      __const char *__restrict __remuser,
		      __const char *__restrict __cmd, int *__restrict __fd2p));

/* Call `rexecd' at port RPORT on remote machine *AHOST to execute
   CMD.  The process runs at the remote machine using the ID of user
   NAME whose cleartext password is PASSWD.  In *FD2P the descriptor
   to the socket for the connection is returned.  When the function
   returns *AHOST contains the official host name.  */
extern int rexec __P ((char **__restrict __ahost, int __rport,
		       __const char *__restrict __name,
		       __const char *__restrict __pass,
		       __const char *__restrict __cmd,
		       int *__restrict __fd2p));

/* Check whether user REMUSER on system RHOST is allowed to login as LOCUSER.
   If SUSER is not zero the user tries to become superuser.  Return 0 if
   it is possible.  */
extern int ruserok __P ((__const char *__rhost, int __suser,
			 __const char *__remuser, __const char *__locuser));

/* Try to allocate reserved port, returning a descriptor for a socket opened
   at this port or -1 if unsuccessful.  The search for an available port
   will start at ALPORT and continues with lower numbers.  */
extern int rresvport __P ((int *__alport));
#endif


/* Extension from POSIX.1g.  */
#ifdef	__USE_POSIX
/* Structure to contain information about address of a service provider.  */
struct addrinfo
{
  int ai_flags;			/* Input flags.  */
  int ai_family;		/* Protocol family for socket.  */
  int ai_socktype;		/* Socket type.  */
  int ai_protocol;		/* Protocol for socket.  */
  int ai_addrlen;		/* Length of socket address.  */
  struct sockaddr *ai_addr;	/* Socket address for socket.  */
  char *ai_canonname;		/* Canonical name for service location.  */
  struct addrinfo *ai_next;	/* Pointer to next in list.  */
};

/* Possible values for `ai_flags' field in `addrinfo' structure.  */
# define AI_PASSIVE	1	/* Socket address is intended for `bind'.  */
# define AI_CANONNAME	2	/* Request for canonical name.  */
# define AI_NUMERICHOST	4	/* Don't use name resolution.  */

/* Error values for `getaddrinfo' function.  */
# define EAI_BADFLAGS	-1	/* Invalid value for `ai_flags' field.  */
# define EAI_NONAME	-2	/* NAME or SERVICE is unknown.  */
# define EAI_AGAIN	-3	/* Temporary failure in name resolution.  */
# define EAI_FAIL	-4	/* Non-recoverable failure in name res.  */
# define EAI_NODATA	-5	/* No address associated with NAME.  */
# define EAI_FAMILY	-6	/* `ai_family' not supported.  */
# define EAI_SOCKTYPE	-7	/* `ai_socktype' not supported.  */
# define EAI_SERVICE	-8	/* SERVICE not supported for `ai_socktype'.  */
# define EAI_ADDRFAMILY	-9	/* Address family for NAME not supported.  */
# define EAI_MEMORY	-10	/* Memory allocation failure.  */
# define EAI_SYSTEM	-11	/* System error returned in `errno'.  */

# define NI_MAXHOST      1025
# define NI_MAXSERV      32

# define NI_NUMERICHOST	1	/* Don't try to look up hostname.  */
# define NI_NUMERICSERV 2	/* Don't convert port number to name.  */
# define NI_NOFQDN	4	/* Only return nodename portion.  */
# define NI_NAMEREQD	8	/* Don't return numeric addresses.  */
# define NI_DGRAM	16	/* Look up UDP service rather than TCP.  */

/* Translate name of a service location and/or a service name to set of
   socket addresses.  */
extern int getaddrinfo __P ((__const char *__restrict __name,
			     __const char *__restrict __service,
			     __const struct addrinfo *__restrict __req,
			     struct addrinfo **__restrict __pai));

/* Free `addrinfo' structure AI including associated storage.  */
extern void freeaddrinfo __P ((struct addrinfo *__ai));

/* Convert error return from getaddrinfo() to a string.  */
extern char *gai_strerror __P  ((int __ecode));

/* Translate a socket address to a location and service name.  */
extern int getnameinfo __P ((__const struct sockaddr *__restrict __sa,
			     socklen_t __salen,
			     char *__restrict __host, size_t __hostlen,
			     char *__restrict __serv, size_t __servlen,
			     int __flags));

#endif	/* POSIX */

__END_DECLS

#endif	/* netdb.h */