1
2 /* Copyright (C) 2005 - 2010, Daniel Stenberg
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
17 #ifdef HAVE_SYS_TIME_H
18 #include <sys/time.h>
19 #endif
20
21 #include "ares.h"
22 #include "ares_private.h"
23
ares_getsock(ares_channel channel,ares_socket_t * socks,int numsocks)24 int ares_getsock(ares_channel channel,
25 ares_socket_t *socks,
26 int numsocks) /* size of the 'socks' array */
27 {
28 struct server_state *server;
29 int i;
30 int sockindex=0;
31 int bitmap = 0;
32 unsigned int setbits = 0xffffffff;
33
34 /* Are there any active queries? */
35 int active_queries = !ares__is_list_empty(&(channel->all_queries));
36
37 for (i = 0;
38 (i < channel->nservers) && (sockindex < ARES_GETSOCK_MAXNUM);
39 i++)
40 {
41 server = &channel->servers[i];
42 /* We only need to register interest in UDP sockets if we have
43 * outstanding queries.
44 */
45 if (active_queries && server->udp_socket != ARES_SOCKET_BAD)
46 {
47 if(sockindex >= numsocks)
48 break;
49 socks[sockindex] = server->udp_socket;
50 bitmap |= ARES_GETSOCK_READABLE(setbits, sockindex);
51 sockindex++;
52 }
53 /* We always register for TCP events, because we want to know
54 * when the other side closes the connection, so we don't waste
55 * time trying to use a broken connection.
56 */
57 if (server->tcp_socket != ARES_SOCKET_BAD)
58 {
59 if(sockindex >= numsocks)
60 break;
61 socks[sockindex] = server->tcp_socket;
62 bitmap |= ARES_GETSOCK_READABLE(setbits, sockindex);
63
64 if (server->qhead && active_queries)
65 /* then the tcp socket is also writable! */
66 bitmap |= ARES_GETSOCK_WRITABLE(setbits, sockindex);
67
68 sockindex++;
69 }
70 }
71 return bitmap;
72 }
73