src/include/gnunet_resolver_service.h

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009 Christian Grothoff (and other contributing authors)
   4
   5      GNUnet is free software; you can redistribute it and/or modify
   6      it under the terms of the GNU General Public License as published
   7      by the Free Software Foundation; either version 2, or (at your
   8      option) any later version.
   9
  10      GNUnet is distributed in the hope that it will be useful, but
  11      WITHOUT ANY WARRANTY; without even the implied warranty of
  12      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13      General Public License for more details.
  14
  15      You should have received a copy of the GNU General Public License
  16      along with GNUnet; see the file COPYING.  If not, write to the
  17      Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18      Boston, MA 02111-1307, USA.
  19 */
  20
  21 /**
  22  * @file include/gnunet_resolver_service.h
  23  * @brief functions related to doing DNS lookups
  24  * @author Christian Grothoff
  25  */
  26
  27 #ifndef GNUNET_RESOLVER_SERVICE_H
  28 #define GNUNET_RESOLVER_SERVICE_H
  29
  30 #ifdef __cplusplus
  31 extern "C"
  32 {
  33 #if 0                           /* keep Emacsens' auto-indent happy */
  34 }
  35 #endif
  36 #endif
  37
  38 #include "gnunet_configuration_lib.h"
  39 #include "gnunet_scheduler_lib.h"
  40 #include "gnunet_time_lib.h"
  41
  42
  43 /**
  44  * Function called by the resolver for each address obtained from DNS.
  45  *
  46  * @param cls closure
  47  * @param addr one of the addresses of the host, NULL for the last address
  48  * @param addrlen length of the address
  49  */
  50 typedef void (*GNUNET_RESOLVER_AddressCallback) (void *cls,
  51                                                  const struct sockaddr * addr,
  52                                                  socklen_t addrlen);
  53
  54
  55 /**
  56  * Handle to a request given to the resolver.  Can be used to cancel
  57  * the request prior to the timeout or successful execution.
  58  */
  59 struct GNUNET_RESOLVER_RequestHandle;
  60
  61 /**
  62  * Create the connection to the resolver service.
  63  *
  64  * @param cfg configuration to use
  65  */
  66 void GNUNET_RESOLVER_connect (const struct GNUNET_CONFIGURATION_Handle *c);
  67
  68
  69 /**
  70  * Destroy the connection to the resolver service.
  71  */
  72 void GNUNET_RESOLVER_disconnect (void);
  73
  74
  75 /**
  76  * Convert a string to one or more IP addresses.
  77  *
  78  * @param hostname the hostname to resolve
  79  * @param domain AF_INET or AF_INET6; use AF_UNSPEC for "any"
  80  * @param callback function to call with addresses
  81  * @param callback_cls closure for callback
  82  * @param timeout how long to try resolving
  83  * @return handle that can be used to cancel the request, NULL on error
  84  */
  85 struct GNUNET_RESOLVER_RequestHandle *GNUNET_RESOLVER_ip_get (const char
  86                                                               *hostname,
  87                                                               int domain,
  88                                                               struct
  89                                                               GNUNET_TIME_Relative
  90                                                               timeout,
  91                                                               GNUNET_RESOLVER_AddressCallback
  92                                                               callback,
  93                                                               void
  94                                                               *callback_cls);
  95
  96
  97 /**
  98  * Resolve our hostname to an IP address.
  99  *
 100  * @param cfg configuration to use
 101  * @param domain AF_INET or AF_INET6; use AF_UNSPEC for "any"
 102  * @param callback function to call with addresses
 103  * @param cls closure for callback
 104  * @param timeout how long to try resolving
 105  * @return handle that can be used to cancel the request, NULL on error
 106  */
 107 struct GNUNET_RESOLVER_RequestHandle *GNUNET_RESOLVER_hostname_resolve (int
 108                                                                         domain,
 109                                                                         struct
 110                                                                         GNUNET_TIME_Relative
 111                                                                         timeout,
 112                                                                         GNUNET_RESOLVER_AddressCallback
 113                                                                         callback,
 114                                                                         void
 115                                                                         *cls);
 116
 117
 118 /**
 119  * Function called by the resolver for each hostname obtained from DNS.
 120  *
 121  * @param cls closure
 122  * @param hostname one of the names for the host, NULL
 123  *        on the last call to the callback
 124  */
 125 typedef void (*GNUNET_RESOLVER_HostnameCallback) (void *cls,
 126                                                   const char *hostname);
 127
 128 /**
 129  * Get local fully qualified domain name
 130  *
 131  * @return local hostname, caller must free
 132  */
 133 char *GNUNET_RESOLVER_local_fqdn_get (void);
 134
 135
 136 /**
 137  * Perform a reverse DNS lookup.
 138  *
 139  * @param cfg configuration to use
 140  * @param sa host address
 141  * @param salen length of host address
 142  * @param do_resolve use GNUNET_NO to return numeric hostname
 143  * @param timeout how long to try resolving
 144  * @param callback function to call with hostnames
 145  * @param cls closure for callback
 146  * @return handle that can be used to cancel the request, NULL on error
 147  */
 148 struct GNUNET_RESOLVER_RequestHandle *GNUNET_RESOLVER_hostname_get (const struct
 149                                                                     sockaddr
 150                                                                     *sa,
 151                                                                     socklen_t
 152                                                                     salen,
 153                                                                     int
 154                                                                     do_resolve,
 155                                                                     struct
 156                                                                     GNUNET_TIME_Relative
 157                                                                     timeout,
 158                                                                     GNUNET_RESOLVER_HostnameCallback
 159                                                                     callback,
 160                                                                     void *cls);
 161
 162
 163 /**
 164  * Cancel a request that is still pending with the resolver.
 165  * Note that a client MUST NOT cancel a request that has
 166  * been completed (i.e, the callback has been called to
 167  * signal timeout or the final result).
 168  *
 169  * @param rh handle of request to cancel
 170  */
 171 void GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *rh);
 172
 173
 174 #if 0                           /* keep Emacsens' auto-indent happy */
 175 {
 176 #endif
 177 #ifdef __cplusplus
 178 }
 179 #endif
 180
 181 /* ifndef GNUNET_RESOLVER_SERVICE_H */
 182 #endif
 183 /* end of gnunet_resolver_service.h */