lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 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 | |
| 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 | */ |
| 26 | void ares_cancel(ares_channel channel) |
| 27 | { |
| 28 | struct query *query; |
| 29 | struct list_node list_head_copy; |
| 30 | struct list_node* list_head; |
| 31 | struct list_node* list_node; |
| 32 | int i; |
| 33 | |
| 34 | if (!ares__is_list_empty(&(channel->all_queries))) |
| 35 | { |
| 36 | /* Swap list heads, so that only those queries which were present on entry |
| 37 | * into this function are cancelled. New queries added by callbacks of |
| 38 | * queries being cancelled will not be cancelled themselves. |
| 39 | */ |
| 40 | list_head = &(channel->all_queries); |
| 41 | list_head_copy.prev = list_head->prev; |
| 42 | list_head_copy.next = list_head->next; |
| 43 | list_head_copy.prev->next = &list_head_copy; |
| 44 | list_head_copy.next->prev = &list_head_copy; |
| 45 | list_head->prev = list_head; |
| 46 | list_head->next = list_head; |
| 47 | for (list_node = list_head_copy.next; list_node != &list_head_copy; ) |
| 48 | { |
| 49 | query = list_node->data; |
| 50 | list_node = list_node->next; /* since we're deleting the query */ |
| 51 | query->callback(query->arg, ARES_ECANCELLED, 0, NULL, 0); |
| 52 | ares__free_query(query); |
| 53 | } |
| 54 | } |
| 55 | if (!(channel->flags & ARES_FLAG_STAYOPEN) && ares__is_list_empty(&(channel->all_queries))) |
| 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 | } |