ares.h

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/* Copyright 1998 by the Massachusetts Institute of Technology.
 *
 * Permission to use, copy, modify, and distribute this
 * software and its documentation for any purpose and without
 * fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting
 * documentation, and that the name of M.I.T. not be used in
 * advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.
 * M.I.T. makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is"
 * without express or implied warranty.
 */
 
#ifndef ARES__H
#define ARES__H
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#ifdef WIN32
   #include <winsock2.h>
   #include <stdlib.h>
   #include <errno.h>
   #include <io.h>
   #include <string.h>
   #include <stdio.h>
   #include <WS2tcpip.h>
   // Remove compiler warnings: "warning C4996: 'xxxxx': The POSIX name for this item is deprecated. Instead, use the ISO C++ conformant name: _xxxxxx."  
   #define strdup _strdup 
   #define stricmp _stricmp 
   #define strnicmp _strnicmp 
   #define write _write
#endif
 
// include this early to resolve some build issues
// FIXME: maybe we need to update our copy of c-ares
//        with the upstream version that resolves
//        a lot of these issues
#include "ares_nameser.h"
 
#if !defined(DNS__16BIT)
#  define DNS__16BIT(p)             (((p)[0] << 8) | (p)[1])   
#  define DNS__32BIT(p)         (((p)[0] << 24) | ((p)[1] << 16) | \
                      ((p)[2] << 8) | (p)[3])
#  define DNS_HEADER_QDCOUNT(h)     DNS__16BIT((h) + 4)
#  define DNS_HEADER_ANCOUNT(h)     DNS__16BIT((h) + 6)
#  define DNS_HEADER_NSCOUNT(h)     DNS__16BIT((h) + 8)
#  define DNS_HEADER_ARCOUNT(h)     DNS__16BIT((h) + 10)
#  define DNS_RR_TYPE(r)            DNS__16BIT(r)
#  define DNS_RR_LEN(r)             DNS__16BIT((r) + 8)
#  define DNS_RR_TTL(r)             DNS__32BIT((r) + 4)
#endif
 
#if defined(__cplusplus)
extern "C" {
#endif
 
#if defined(__APPLE__)
#include "ares_nameser.h"
#if !defined(MAC_OS_X_VERSION_MIN_REQUIRED) || (MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_2)
#include "ares_nameser.h"
#endif
#endif
 
#include <sys/types.h>
#if defined(__ANDROID__)
#include <sys/select.h>
#endif
#ifndef WIN32
/* why was this commented out?! ah, it was a 'fix for windows' */
#include <netinet/in.h>
#endif
 
#include "ares_socketfunc.h"
 
#define ARES_SUCCESS        0
 
/* Server error codes (ARES_ENODATA indicates no relevant answer) */
#define ARES_ENODATA        1
#define ARES_EFORMERR       2
#define ARES_ESERVFAIL      3
#define ARES_ENOTFOUND      4
#define ARES_ENOTIMP        5
#define ARES_EREFUSED       6
 
/* Locally generated error codes */
#define ARES_EBADQUERY      7
#define ARES_EBADNAME       8
#define ARES_EBADFAMILY     9
#define ARES_EBADRESP       10
#define ARES_ECONNREFUSED   11
#define ARES_ETIMEOUT       12
#define ARES_EOF        13
#define ARES_EFILE      14
#define ARES_ENOMEM     15
#define ARES_EDESTRUCTION   16
 
/* Flag values */
#define ARES_FLAG_USEVC     (1 << 0)
#define ARES_FLAG_PRIMARY   (1 << 1)
#define ARES_FLAG_IGNTC     (1 << 2)
#define ARES_FLAG_NORECURSE (1 << 3)
#define ARES_FLAG_STAYOPEN  (1 << 4)
#define ARES_FLAG_NOSEARCH  (1 << 5)
#define ARES_FLAG_NOALIASES (1 << 6)
#define ARES_FLAG_NOCHECKRESP   (1 << 7)
#define ARES_FLAG_TRY_NEXT_SERVER_ON_RCODE3 (1 << 8) /* when rcode of 3 ('No such name') is recvd */
 
/* Option mask values */
#define ARES_OPT_FLAGS      (1 << 0)
#define ARES_OPT_TIMEOUT    (1 << 1)
#define ARES_OPT_TRIES      (1 << 2)
#define ARES_OPT_NDOTS      (1 << 3)
#define ARES_OPT_UDP_PORT   (1 << 4)
#define ARES_OPT_TCP_PORT   (1 << 5)
#define ARES_OPT_SERVERS    (1 << 6)
#define ARES_OPT_DOMAINS    (1 << 7)
#define ARES_OPT_LOOKUPS    (1 << 8)
 
/* Capability mask values */
 
#define ARES_CAP_IPV6       (1 << 0)
 
typedef enum ares_poll_action {
  ARES_POLLACTION_NULL=     (0),
  ARES_POLLACTION_OPEN=     (1),    // ares just opened this
  ARES_POLLACTION_CLOSE=    (2),    // ares just closed this
  ARES_POLLACTION_WRITEON=  (3),    // tell ares when writable
  ARES_POLLACTION_WRITEOFF= (4) // don't tell ares when writable
} ares_poll_action_t;
struct ares_channeldata;
typedef void (ares_poll_cb_func)(void *cb_data, struct ares_channeldata* chan, int sockidx,
  int fd, int using_tcp, ares_poll_action_t act);
 
#if defined(WIN32) || defined(sun)
typedef unsigned char u_int8_t;
#endif
 
#ifdef USE_IPV6
struct multiFamilyAddr {
  u_int8_t family;
  struct in6_addr addr6;
  struct in_addr addr;
};
#endif
 
struct ares_options {
  int flags;
  int timeout;
  int tries;
  int ndots;
  unsigned short udp_port;
  unsigned short tcp_port;
#ifdef USE_IPV6
  struct multiFamilyAddr *servers;
#else
  struct in_addr *servers;
#endif
  int nservers;
  char **domains;
  int ndomains;
  char *lookups;
};
 
struct hostent;
struct timeval;
struct ares_channeldata;
typedef struct ares_channeldata *ares_channel;
typedef void (*ares_callback)(void *arg, int status, unsigned char *abuf,
                  int alen);
typedef void (*ares_host_callback)(void *arg, int status,
                   struct hostent *hostent);
 
extern int ares_init(ares_channel *channelptr);
extern int ares_init_with_socket_function(ares_channel *channelptr, socket_function_ptr);
 
extern  int ares_capabilities(int capmask);
 
extern  int ares_init_options(ares_channel *channelptr, struct ares_options *options,
                              int optmask);
 
extern  int ares_init_options_with_socket_function(ares_channel *channelptr, struct ares_options *options,
                                                   int optmask, socket_function_ptr);
extern  void ares_destroy(ares_channel channel);
extern  void ares_destroy_suppress_callbacks(ares_channel channel);
 
extern  void ares_destroy_internal(ares_channel channel, int suppressCallbacks);
 
extern  void ares_send(ares_channel channel, const unsigned char *qbuf, int qlen,
            ares_callback callback, void *arg);
extern  void ares_query(ares_channel channel, const char *name, int dnsclass,
            int type, ares_callback callback, void *arg);
extern  void ares_search(ares_channel channel, const char *name, int dnsclass,
            int type, ares_callback callback, void *arg);
extern  void ares_gethostbyname(ares_channel channel, const char *name, int family,
                ares_host_callback callback, void *arg);
extern  void ares_gethostbyaddr(ares_channel channel, const void *addr, int addrlen,
                int family, ares_host_callback callback, void *arg);
extern   int hostfile_lookup(const char *name, struct hostent **host);
 
extern  int ares_fds(ares_channel channel, fd_set *read_fds, fd_set *write_fds);
extern  struct timeval *ares_timeout(ares_channel channel, struct timeval *maxtv,
                    struct timeval *tv);
extern  void ares_process(ares_channel channel, fd_set *read_fds, fd_set *write_fds);
extern void ares_process_set_poll_cb(ares_channel channel, ares_poll_cb_func* cb_func, void *cb_data);
extern void ares_process_poll(ares_channel channel, int server_idx,
        int rdFd, int wrFd, time_t now);
 
 
extern  int ares_mkquery(const char *name, int dnsclass, int type, unsigned short id,
            int rd, unsigned char **buf, int *buflen);
extern  int ares_expand_name(const unsigned char *encoded, const unsigned char *abuf,
                int alen, char **s, long *enclen);
extern  int ares_parse_a_reply(const unsigned char *abuf, int alen,
                struct hostent **host);
extern  int ares_parse_ptr_reply(const unsigned char *abuf, int alen, const void *addr,
                int addrlen, int family, struct hostent **host);
extern  void ares_free_string(char *str);
extern  void ares_free_hostent(struct hostent *host);
extern  const char *ares_strerror(int code);
extern  void ares_free_errmem(char *mem);
 
 
#if defined(WIN32) || defined (__CYGWIN__) || defined (__ANDROID__)
 
#define T_A             1               /* host address */
#define T_NS            2               /* authoritative server */
#define T_MD            3               /* mail destination */
#define T_MF            4               /* mail forwarder */
#define T_CNAME         5               /* canonical name */
#define T_SOA           6               /* start of authority zone */
#define T_MB            7               /* mailbox domain name */
#define T_MG            8               /* mail group member */
#define T_MR            9               /* mail rename name */
#define T_NULL          10              /* null resource record */
#define T_WKS           11              /* well known service */
#define T_PTR           12              /* domain name pointer */
#define T_HINFO         13              /* host information */
#define T_MINFO         14              /* mailbox information */
#define T_MX            15              /* mail routing information */
#define T_TXT           16              /* text strings */
#define T_RP            17              /* responsible person */
#define T_AFSDB         18              /* AFS cell database */
#define T_X25           19              /* X_25 calling address */
#define T_ISDN          20              /* ISDN calling address */
#define T_RT            21              /* router */
#define T_NSAP          22              /* NSAP address */
#define T_NSAP_PTR      23              /* reverse NSAP lookup (deprecated) */
#define T_SIG           24              /* security signature */
#define T_KEY           25              /* security key */
#define T_PX            26              /* X.400 mail mapping */
#define T_GPOS          27              /* geographical position (withdrawn) */
#define T_AAAA          28              /* IP6 Address */
#define T_LOC           29              /* Location Information */
        /* non standard */
#define T_UINFO         100             /* user (finger) information */
#define T_UID           101             /* user ID */
#define T_GID           102             /* group ID */
#define T_UNSPEC        103             /* Unspecified format (binary data) */
        /* Query type values which do not appear in resource records */
#define T_AXFR          252             /* transfer zone of authority */
#define T_MAILB         253             /* transfer mailbox records */
#define T_MAILA         254             /* transfer mail agent records */
#define T_ANY           255             /* wildcard match */
 
/* These are now defined in ares_nameserv.h
   Some compilers error when the macro is redefined so
   we disable them without the macro LEGACY_DEFINES */
#ifdef ARES_LEGACY_DEFINES
#define C_IN 1
#define C_CHAOS 3
#define C_HS 4
#define C_ANY 255
 
#define INDIR_MASK 0xc0
#define HFIXEDSZ 12
#define QFIXEDSZ 4
#define RRFIXEDSZ 10
 
#define NOERROR 0
#define FORMERR 1
#define SERVFAIL 2
#define NXDOMAIN 3
#define NOTIMP 4
#define REFUSED 5
 
#define PACKETSZ 512 
#endif
 
#ifndef MAXHOSTNAMELEN
#define MAXHOSTNAMELEN 256
 
#ifndef MAXCDNAME
#define MAXCDNAME   255     /* maximum compressed domain name */
#endif
 
#define NS_DEFAULTPORT 53 
#define NAMESERVER_PORT NS_DEFAULTPORT 
 
#ifndef QUERY
#define QUERY 0
#endif
 
#ifndef MAXLABEL
#define MAXLABEL 63
#endif 
 
#endif
 
#endif
 
#if defined(__cplusplus)
}
#endif
 
 
#endif /* ARES__H */