1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
|
/* MIT License
*
* Copyright (c) 1998 Massachusetts Institute of Technology
* Copyright (c) The c-ares project and its contributors
*
* 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_private.h"
#include <assert.h>
static void ares__requeue_queries(ares_conn_t *conn,
ares_status_t requeue_status)
{
ares_query_t *query;
ares_timeval_t now;
ares__tvnow(&now);
while ((query = ares__llist_first_val(conn->queries_to_conn)) != NULL) {
ares__requeue_query(query, &now, requeue_status, ARES_TRUE, NULL);
}
}
void ares__close_connection(ares_conn_t *conn, ares_status_t requeue_status)
{
ares_server_t *server = conn->server;
ares_channel_t *channel = server->channel;
/* Unlink */
ares__llist_node_claim(
ares__htable_asvp_get_direct(channel->connnode_by_socket, conn->fd));
ares__htable_asvp_remove(channel->connnode_by_socket, conn->fd);
if (conn->flags & ARES_CONN_FLAG_TCP) {
/* Reset any existing input and output buffer. */
ares__buf_consume(server->tcp_parser, ares__buf_len(server->tcp_parser));
ares__buf_consume(server->tcp_send, ares__buf_len(server->tcp_send));
server->tcp_conn = NULL;
}
/* Requeue queries to other connections */
ares__requeue_queries(conn, requeue_status);
ares__llist_destroy(conn->queries_to_conn);
SOCK_STATE_CALLBACK(channel, conn->fd, 0, 0);
ares__close_socket(channel, conn->fd);
ares_free(conn);
}
void ares__close_sockets(ares_server_t *server)
{
ares__llist_node_t *node;
while ((node = ares__llist_node_first(server->connections)) != NULL) {
ares_conn_t *conn = ares__llist_node_val(node);
ares__close_connection(conn, ARES_SUCCESS);
}
}
void ares__check_cleanup_conns(const ares_channel_t *channel)
{
ares__slist_node_t *snode;
if (channel == NULL) {
return; /* LCOV_EXCL_LINE: DefensiveCoding */
}
/* Iterate across each server */
for (snode = ares__slist_node_first(channel->servers); snode != NULL;
snode = ares__slist_node_next(snode)) {
ares_server_t *server = ares__slist_node_val(snode);
ares__llist_node_t *cnode;
/* Iterate across each connection */
cnode = ares__llist_node_first(server->connections);
while (cnode != NULL) {
ares__llist_node_t *next = ares__llist_node_next(cnode);
ares_conn_t *conn = ares__llist_node_val(cnode);
ares_bool_t do_cleanup = ARES_FALSE;
cnode = next;
/* Has connections, not eligible */
if (ares__llist_len(conn->queries_to_conn)) {
continue;
}
/* If we are configured not to stay open, close it out */
if (!(channel->flags & ARES_FLAG_STAYOPEN)) {
do_cleanup = ARES_TRUE;
}
/* If the associated server has failures, close it out. Resetting the
* connection (and specifically the source port number) can help resolve
* situations where packets are being dropped.
*/
if (conn->server->consec_failures > 0) {
do_cleanup = ARES_TRUE;
}
/* If the udp connection hit its max queries, always close it */
if (!(conn->flags & ARES_CONN_FLAG_TCP) && channel->udp_max_queries > 0 &&
conn->total_queries >= channel->udp_max_queries) {
do_cleanup = ARES_TRUE;
}
if (!do_cleanup) {
continue;
}
/* Clean it up */
ares__close_connection(conn, ARES_SUCCESS);
}
}
}
|
