1
2/* Copyright (C) 2004 by Daniel Stenberg et al
3 *
4 * Permission to use, copy, modify, and distribute this software and its
5 * documentation for any purpose and without fee is hereby granted, provided
6 * that the above copyright notice appear in all copies and that both that
7 * copyright notice and this permission notice appear in supporting
8 * documentation, and that the name of M.I.T. not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission.  M.I.T. makes no representations about the
11 * suitability of this software for any purpose.  It is provided "as is"
12 * without express or implied warranty.
13 */
14
15#include "ares_setup.h"
16#include <assert.h>
17#include <stdlib.h>
18#include "ares.h"
19#include "ares_private.h"
20
21/*
22 * ares_cancel() cancels all ongoing requests/resolves that might be going on
23 * on the given channel. It does NOT kill the channel, use ares_destroy() for
24 * that.
25 */
26void ares_cancel(ares_channel channel)
27{
28  struct query *query;
29  struct list_node* list_head;
30  struct list_node* list_node;
31  int i;
32
33  list_head = &(channel->all_queries);
34  for (list_node = list_head->next; list_node != list_head; )
35  {
36    query = list_node->data;
37    list_node = list_node->next;  /* since we're deleting the query */
38    query->callback(query->arg, ARES_ECANCELLED, 0, NULL, 0);
39    ares__free_query(query);
40  }
41#ifndef NDEBUG
42  /* Freeing the query should remove it from all the lists in which it sits,
43   * so all query lists should be empty now.
44   */
45  assert(ares__is_list_empty(&(channel->all_queries)));
46  for (i = 0; i < ARES_QID_TABLE_SIZE; i++)
47    {
48      assert(ares__is_list_empty(&(channel->queries_by_qid[i])));
49    }
50  for (i = 0; i < ARES_TIMEOUT_TABLE_SIZE; i++)
51    {
52      assert(ares__is_list_empty(&(channel->queries_by_timeout[i])));
53    }
54#endif
55  if (!(channel->flags & ARES_FLAG_STAYOPEN))
56  {
57    if (channel->servers)
58    {
59      for (i = 0; i < channel->nservers; i++)
60        ares__close_sockets(channel, &channel->servers[i]);
61    }
62  }
63}
64