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/*-
* Copyright (c) 2006 The FreeBSD Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <stdlib.h>
#include "namespace.h"
#include "reentrant.h"
#include "un-namespace.h"
#undef _res
struct __res_state _res;
static thread_key_t res_key;
static once_t res_init_once = ONCE_INITIALIZER;
static int res_thr_keycreated = 0;
static void
free_res(void *ptr)
{
res_state statp = ptr;
if (statp->_u._ext.ext != NULL)
res_ndestroy(statp);
free(statp);
}
static void
res_keycreate(void)
{
res_thr_keycreated = thr_keycreate(&res_key, free_res) == 0;
}
static res_state
res_check_reload(res_state statp)
{
struct timespec now;
struct stat sb;
if ((statp->options & RES_INIT) == 0 || statp->reload_period == 0) {
return (statp);
}
if (clock_gettime(CLOCK_MONOTONIC_FAST, &now) != 0 ||
(now.tv_sec - statp->conf_stat) < statp->reload_period) {
return (statp);
}
statp->conf_stat = now.tv_sec;
if (stat(_PATH_RESCONF, &sb) == 0 &&
(sb.st_mtim.tv_sec != statp->conf_mtim.tv_sec ||
sb.st_mtim.tv_nsec != statp->conf_mtim.tv_nsec)) {
statp->options &= ~RES_INIT;
}
return (statp);
}
res_state
__res_state(void)
{
res_state statp;
if (thr_main() != 0)
return res_check_reload(&_res);
if (thr_once(&res_init_once, res_keycreate) != 0 ||
!res_thr_keycreated)
return (&_res);
statp = thr_getspecific(res_key);
if (statp != NULL)
return res_check_reload(statp);
statp = calloc(1, sizeof(*statp));
if (statp == NULL)
return (&_res);
#ifdef __BIND_RES_TEXT
statp->options = RES_TIMEOUT; /* Motorola, et al. */
#endif
if (thr_setspecific(res_key, statp) == 0)
return (statp);
free(statp);
return (&_res);
}
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