gio/gsocketaddressenumerator.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2008 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include "config.h"
  22 #include "gsocketaddressenumerator.h"
  23 #include "glibintl.h"
  24
  25 #include "gsimpleasyncresult.h"
  26
  27 #include "gioalias.h"
  28
  29 G_DEFINE_ABSTRACT_TYPE (GSocketAddressEnumerator, g_socket_address_enumerator, G_TYPE_OBJECT);
  30
  31 static void            g_socket_address_enumerator_real_next_async  (GSocketAddressEnumerator  *enumerator,
  32                                                                      GCancellable              *cancellable,
  33                                                                      GAsyncReadyCallback        callback,
  34                                                                      gpointer                   user_data);
  35 static GSocketAddress *g_socket_address_enumerator_real_next_finish (GSocketAddressEnumerator  *enumerator,
  36                                                                      GAsyncResult              *result,
  37                                                                      GError                   **error);
  38
  39 static void
  40 g_socket_address_enumerator_init (GSocketAddressEnumerator *enumerator)
  41 {
  42 }
  43
  44 static void
  45 g_socket_address_enumerator_class_init (GSocketAddressEnumeratorClass *enumerator_class)
  46 {
  47   enumerator_class->next_async = g_socket_address_enumerator_real_next_async;
  48   enumerator_class->next_finish = g_socket_address_enumerator_real_next_finish;
  49 }
  50
  51 /**
  52  * g_socket_address_enumerator_next:
  53  * @enumerator: a #GSocketAddressEnumerator
  54  * @cancellable: optional #GCancellable object, %NULL to ignore.
  55  * @error: a #GError.
  56  *
  57  * Retrieves the next #GSocketAddress from @enumerator. Note that this
  58  * may block for some amount of time. (Eg, a #GNetworkAddress may need
  59  * to do a DNS lookup before it can return an address.) Use
  60  * g_socket_address_enumerator_next_async() if you need to avoid
  61  * blocking.
  62  *
  63  * If @enumerator is expected to yield addresses, but for some reason
  64  * is unable to (eg, because of a DNS error), then the first call to
  65  * g_socket_address_enumerator_next() will return an appropriate error
  66  * in *@error. However, if the first call to
  67  * g_socket_address_enumerator_next() succeeds, then any further
  68  * internal errors (other than @cancellable being triggered) will be
  69  * ignored.
  70  *
  71  * Return value: a #GSocketAddress (owned by the caller), or %NULL on
  72  *     error (in which case *@error will be set) or if there are no
  73  *     more addresses.
  74  */
  75 GSocketAddress *
  76 g_socket_address_enumerator_next (GSocketAddressEnumerator  *enumerator,
  77                                   GCancellable              *cancellable,
  78                                   GError                   **error)
  79 {
  80   GSocketAddressEnumeratorClass *klass;
  81
  82   g_return_val_if_fail (G_IS_SOCKET_ADDRESS_ENUMERATOR (enumerator), NULL);
  83
  84   klass = G_SOCKET_ADDRESS_ENUMERATOR_GET_CLASS (enumerator);
  85
  86   return (* klass->next) (enumerator, cancellable, error);
  87 }
  88
  89 /* Default implementation just calls the synchronous method; this can
  90  * be used if the implementation already knows all of its addresses,
  91  * and so the synchronous method will never block.
  92  */
  93 static void
  94 g_socket_address_enumerator_real_next_async (GSocketAddressEnumerator *enumerator,
  95                                              GCancellable             *cancellable,
  96                                              GAsyncReadyCallback       callback,
  97                                              gpointer                  user_data)
  98 {
  99   GSimpleAsyncResult *result;
 100   GSocketAddress *address;
 101   GError *error = NULL;
 102
 103   result = g_simple_async_result_new (G_OBJECT (enumerator),
 104                                       callback, user_data,
 105                                       g_socket_address_enumerator_real_next_async);
 106   address = g_socket_address_enumerator_next (enumerator, cancellable, &error);
 107   if (address)
 108     g_simple_async_result_set_op_res_gpointer (result, address, NULL);
 109   else if (error)
 110     {
 111       g_simple_async_result_set_from_error (result, error);
 112       g_error_free (error);
 113     }
 114   g_simple_async_result_complete_in_idle (result);
 115   g_object_unref (result);
 116 }
 117
 118 /**
 119  * g_socket_address_enumerator_next_async:
 120  * @enumerator: a #GSocketAddressEnumerator
 121  * @cancellable: optional #GCancellable object, %NULL to ignore.
 122  * @callback: a #GAsyncReadyCallback to call when the request is satisfied
 123  * @user_data: the data to pass to callback function
 124  *
 125  * Asynchronously retrieves the next #GSocketAddress from @enumerator
 126  * and then calls @callback, which must call
 127  * g_socket_address_enumerator_next_finish() to get the result.
 128  */
 129 void
 130 g_socket_address_enumerator_next_async (GSocketAddressEnumerator *enumerator,
 131                                         GCancellable             *cancellable,
 132                                         GAsyncReadyCallback       callback,
 133                                         gpointer                  user_data)
 134 {
 135   GSocketAddressEnumeratorClass *klass;
 136
 137   g_return_if_fail (G_IS_SOCKET_ADDRESS_ENUMERATOR (enumerator));
 138
 139   klass = G_SOCKET_ADDRESS_ENUMERATOR_GET_CLASS (enumerator);
 140
 141   (* klass->next_async) (enumerator, cancellable, callback, user_data);
 142 }
 143
 144 static GSocketAddress *
 145 g_socket_address_enumerator_real_next_finish (GSocketAddressEnumerator  *enumerator,
 146                                               GAsyncResult              *result,
 147                                               GError                   **error)
 148 {
 149   GSimpleAsyncResult *simple;
 150
 151   g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (result), NULL);
 152   simple = G_SIMPLE_ASYNC_RESULT (result);
 153   g_return_val_if_fail (g_simple_async_result_get_source_tag (simple) == g_socket_address_enumerator_real_next_async, NULL);
 154
 155   if (g_simple_async_result_propagate_error (simple, error))
 156     return NULL;
 157   else
 158     return g_simple_async_result_get_op_res_gpointer (simple);
 159 }
 160
 161 /**
 162  * g_socket_address_enumerator_next_finish:
 163  * @enumerator: a #GSocketAddressEnumerator
 164  * @result: a #GAsyncResult
 165  * @error: a #GError
 166  *
 167  * Retrieves the result of a completed call to
 168  * g_socket_address_enumerator_next_async(). See
 169  * g_socket_address_enumerator_next() for more information about
 170  * error handling.
 171  *
 172  * Return value: a #GSocketAddress (owned by the caller), or %NULL on
 173  *     error (in which case *@error will be set) or if there are no
 174  *     more addresses.
 175  */
 176 GSocketAddress *
 177 g_socket_address_enumerator_next_finish (GSocketAddressEnumerator  *enumerator,
 178                                          GAsyncResult              *result,
 179                                          GError                   **error)
 180 {
 181   GSocketAddressEnumeratorClass *klass;
 182
 183   g_return_val_if_fail (G_IS_SOCKET_ADDRESS_ENUMERATOR (enumerator), NULL);
 184
 185   klass = G_SOCKET_ADDRESS_ENUMERATOR_GET_CLASS (enumerator);
 186
 187   return (* klass->next_finish) (enumerator, result, error);
 188 }
 189
 190 #define __G_SOCKET_ADDRESS_ENUMERATOR_C__
 191 #include "gioaliasdef.c"