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/* MIT License
*
* Copyright (c) 2004 Daniel Stenberg
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* SPDX-License-Identifier: MIT
*/
#include "ares_setup.h"
#include <assert.h>
#include "ares.h"
#include "ares_private.h"
/*
* ares_cancel() cancels all ongoing requests/resolves that might be going on
* on the given channel. It does NOT kill the channel, use ares_destroy() for
* that.
*/
void ares_cancel(ares_channel_t *channel)
{
if (channel == NULL) {
return;
}
ares__channel_lock(channel);
if (ares__llist_len(channel->all_queries) > 0) {
ares__llist_node_t *node = NULL;
ares__llist_node_t *next = NULL;
/* Swap list heads, so that only those queries which were present on entry
* into this function are cancelled. New queries added by callbacks of
* queries being cancelled will not be cancelled themselves.
*/
ares__llist_t *list_copy = channel->all_queries;
channel->all_queries = ares__llist_create(NULL);
/* Out of memory, this function doesn't return a result code though so we
* can't report to caller */
if (channel->all_queries == NULL) {
channel->all_queries = list_copy;
goto done;
}
node = ares__llist_node_first(list_copy);
while (node != NULL) {
struct query *query;
struct server_connection *conn;
/* Cache next since this node is being deleted */
next = ares__llist_node_next(node);
query = ares__llist_node_claim(node);
conn = query->conn;
query->node_all_queries = NULL;
/* NOTE: its possible this may enqueue new queries */
query->callback(query->arg, ARES_ECANCELLED, 0, NULL);
ares__free_query(query);
/* See if the connection should be cleaned up */
ares__check_cleanup_conn(channel, conn);
node = next;
}
ares__llist_destroy(list_copy);
}
ares_queue_notify_empty(channel);
done:
ares__channel_unlock(channel);
}
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