libpurple/dnsquery.h

   1 /**
   2  * @file dnsquery.h DNS query API
   3  * @ingroup core
   4  */
   5
   6 /* purple
   7  *
   8  * Purple is the legal property of its developers, whose names are too numerous
   9  * to list here.  Please refer to the COPYRIGHT file distributed with this
  10  * source distribution.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
  25  */
  26 #ifndef _PURPLE_DNSQUERY_H_
  27 #define _PURPLE_DNSQUERY_H_
  28
  29 #include <glib.h>
  30 #include "eventloop.h"
  31 #include "account.h"
  32
  33 /**
  34  * An opaque structure representing a DNS query.  The hostname and port
  35  * associated with the query can be retrieved using
  36  * purple_dnsquery_get_host() and purple_dnsquery_get_port().
  37  */
  38 typedef struct _PurpleDnsQueryData PurpleDnsQueryData;
  39
  40 /**
  41  * The "hosts" parameter is a linked list containing pairs of
  42  * one size_t addrlen and one struct sockaddr *addr.  It should
  43  * be free'd by the callback function.
  44  */
  45 typedef void (*PurpleDnsQueryConnectFunction)(GSList *hosts, gpointer data, const char *error_message);
  46
  47 /**
  48  * Callbacks used by the UI if it handles resolving DNS
  49  */
  50 typedef void  (*PurpleDnsQueryResolvedCallback) (PurpleDnsQueryData *query_data, GSList *hosts);
  51 typedef void  (*PurpleDnsQueryFailedCallback) (PurpleDnsQueryData *query_data, const gchar *error_message);
  52
  53 /**
  54  * DNS Request UI operations;  UIs should implement this if they want to do DNS
  55  * lookups themselves, rather than relying on the core.
  56  *
  57  * @see @ref ui-ops
  58  */
  59 typedef struct
  60 {
  61         /** If implemented, the UI is responsible for DNS queries */
  62         gboolean (*resolve_host)(PurpleDnsQueryData *query_data,
  63                                  PurpleDnsQueryResolvedCallback resolved_cb,
  64                                  PurpleDnsQueryFailedCallback failed_cb);
  65
  66         /** Called just before @a query_data is freed; this should cancel any
  67          *  further use of @a query_data the UI would make. Unneeded if
  68          *  #resolve_host is not implemented.
  69          */
  70         void (*destroy)(PurpleDnsQueryData *query_data);
  71
  72         void (*_purple_reserved1)(void);
  73         void (*_purple_reserved2)(void);
  74         void (*_purple_reserved3)(void);
  75         void (*_purple_reserved4)(void);
  76 } PurpleDnsQueryUiOps;
  77
  78 #ifdef __cplusplus
  79 extern "C" {
  80 #endif
  81
  82 /**************************************************************************/
  83 /** @name DNS query API                                                   */
  84 /**************************************************************************/
  85 /*@{*/
  86
  87 /**
  88  * Perform an asynchronous DNS query.
  89  *
  90  * @param hostname The hostname to resolve.
  91  * @param port     A port number which is stored in the struct sockaddr.
  92  * @param callback The callback function to call after resolving.
  93  * @param data     Extra data to pass to the callback function.
  94  *
  95  * @return NULL if there was an error, otherwise return a reference to
  96  *         a data structure that can be used to cancel the pending
  97  *         DNS query, if needed.
  98  */
  99 PurpleDnsQueryData *purple_dnsquery_a(const char *hostname, int port, PurpleDnsQueryConnectFunction callback, gpointer data);
 100
 101 /**
 102  * Cancel a DNS query and destroy the associated data structure.
 103  *
 104  * @param query_data The DNS query to cancel.  This data structure
 105  *        is freed by this function.
 106  */
 107 void purple_dnsquery_destroy(PurpleDnsQueryData *query_data);
 108
 109 /**
 110  * Sets the UI operations structure to be used when doing a DNS
 111  * resolve.  The UI operations need only be set if the UI wants to
 112  * handle the resolve itself; otherwise, leave it as NULL.
 113  *
 114  * @param ops The UI operations structure.
 115  */
 116 void purple_dnsquery_set_ui_ops(PurpleDnsQueryUiOps *ops);
 117
 118 /**
 119  * Returns the UI operations structure to be used when doing a DNS
 120  * resolve.
 121  *
 122  * @return The UI operations structure.
 123  */
 124 PurpleDnsQueryUiOps *purple_dnsquery_get_ui_ops(void);
 125
 126 /**
 127  * Get the host associated with a PurpleDnsQueryData
 128  *
 129  * @param query_data The DNS query
 130  * @return The host.
 131  */
 132 char *purple_dnsquery_get_host(PurpleDnsQueryData *query_data);
 133
 134 /**
 135  * Get the port associated with a PurpleDnsQueryData
 136  *
 137  * @param query_data The DNS query
 138  * @return The port.
 139  */
 140 unsigned short purple_dnsquery_get_port(PurpleDnsQueryData *query_data);
 141
 142 /**
 143  * Initializes the DNS query subsystem.
 144  */
 145 void purple_dnsquery_init(void);
 146
 147 /**
 148  * Uninitializes the DNS query subsystem.
 149  */
 150 void purple_dnsquery_uninit(void);
 151
 152 /*@}*/
 153
 154 #ifdef __cplusplus
 155 }
 156 #endif
 157
 158 #endif /* _PURPLE_DNSQUERY_H_ */