blob: 12b93b044aaa20ce3a1474f8ad3880de960c86c3 [file] [log] [blame]
/* $Id$ */
/* Copyright 1998 by the Massachusetts Institute of Technology.
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright
* notice and this permission notice appear in supporting
* documentation, and that the name of M.I.T. not be used in
* advertising or publicity pertaining to distribution of the
* software without specific, written prior permission.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is"
* without express or implied warranty.
#include "setup.h"
#include <sys/time.h>
#include <time.h>
#include "ares.h"
#include "ares_private.h"
/* WARNING: Beware that this is linear in the number of outstanding
* requests! You are probably far better off just calling ares_process()
* once per second, rather than calling ares_timeout() to figure out
* when to next call ares_process().
struct timeval *ares_timeout(ares_channel channel, struct timeval *maxtv,
struct timeval *tvbuf)
struct query *query;
struct list_node* list_head;
struct list_node* list_node;
time_t now;
time_t offset, min_offset; /* these use time_t since some 32 bit systems
still use 64 bit time_t! (like VS2005) */
/* No queries, no timeout (and no fetch of the current time). */
if (ares__is_list_empty(&(channel->all_queries)))
return maxtv;
/* Find the minimum timeout for the current set of queries. */
min_offset = -1;
list_head = &(channel->all_queries);
for (list_node = list_head->next; list_node != list_head;
list_node = list_node->next)
query = list_node->data;
if (query->timeout == 0)
offset = query->timeout - now;
if (offset < 0)
offset = 0;
if (min_offset == -1 || offset < min_offset)
min_offset = offset;
/* If we found a minimum timeout and it's sooner than the one
* specified in maxtv (if any), return it. Otherwise go with
* maxtv.
if (min_offset != -1 && (!maxtv || min_offset <= maxtv->tv_sec))
tvbuf->tv_sec = (long)min_offset;
tvbuf->tv_usec = 0;
return tvbuf;
return maxtv;