freebsd-nq/lib/libc/resolv/res_state.c
Pedro F. Giffuni d915a14ef0 libc: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-25 17:12:48 +00:00

125 lines
3.2 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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"
#include "res_private.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;
struct __res_state_ext *ext;
if ((statp->options & RES_INIT) == 0) {
return (statp);
}
ext = statp->_u._ext.ext;
if (ext == NULL || ext->reload_period == 0) {
return (statp);
}
if (clock_gettime(CLOCK_MONOTONIC_FAST, &now) != 0 ||
(now.tv_sec - ext->conf_stat) < ext->reload_period) {
return (statp);
}
ext->conf_stat = now.tv_sec;
if (stat(_PATH_RESCONF, &sb) == 0 &&
(sb.st_mtim.tv_sec != ext->conf_mtim.tv_sec ||
sb.st_mtim.tv_nsec != ext->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);
}