1 /* Deallocation functions for the resolver state.
2    Copyright (C) 1995-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 /*
20  * Copyright (c) 1985, 1989, 1993
21  *    The Regents of the University of California.  All rights reserved.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the above copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 4. Neither the name of the University nor the names of its contributors
32  *    may be used to endorse or promote products derived from this software
33  *    without specific prior written permission.
34  *
35  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
36  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
38  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
39  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
40  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
41  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
42  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
43  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
44  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
45  * SUCH DAMAGE.
46  */
47 
48 /*
49  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
50  *
51  * Permission to use, copy, modify, and distribute this software for any
52  * purpose with or without fee is hereby granted, provided that the above
53  * copyright notice and this permission notice appear in all copies, and that
54  * the name of Digital Equipment Corporation not be used in advertising or
55  * publicity pertaining to distribution of the document or software without
56  * specific, written prior permission.
57  *
58  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
59  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
60  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
61  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
62  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
63  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
64  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
65  * SOFTWARE.
66  */
67 
68 /*
69  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
70  *
71  * Permission to use, copy, modify, and distribute this software for any
72  * purpose with or without fee is hereby granted, provided that the above
73  * copyright notice and this permission notice appear in all copies.
74  *
75  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
76  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
77  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
78  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
79  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
80  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
81  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
82  * SOFTWARE.
83  */
84 
85 #include <resolv-internal.h>
86 #include <resolv_context.h>
87 #include <resolv_conf.h>
88 #include <not-cancel.h>
89 #include <stdlib.h>
90 
91 /* Close all open sockets.  If FREE_ADDR is true, deallocate any
92    separately allocated name server addresses.  */
93 void
__res_iclose(res_state statp,bool free_addr)94 __res_iclose (res_state statp, bool free_addr)
95 {
96   if (statp->_vcsock >= 0)
97     {
98       __close_nocancel_nostatus (statp->_vcsock);
99       statp->_vcsock = -1;
100       statp->_flags &= ~(RES_F_VC | RES_F_CONN);
101     }
102   for (int ns = 0; ns < statp->nscount; ns++)
103     if (statp->_u._ext.nsaddrs[ns] != NULL)
104       {
105         if (statp->_u._ext.nssocks[ns] != -1)
106           {
107             __close_nocancel_nostatus (statp->_u._ext.nssocks[ns]);
108             statp->_u._ext.nssocks[ns] = -1;
109           }
110         if (free_addr)
111           {
112             free (statp->_u._ext.nsaddrs[ns]);
113             statp->_u._ext.nsaddrs[ns] = NULL;
114           }
115       }
116   if (free_addr)
117     __resolv_conf_detach (statp);
118 }
libc_hidden_def(__res_iclose)119 libc_hidden_def (__res_iclose)
120 
121 void
122 res_nclose (res_state statp)
123 {
124   __res_iclose (statp, true);
125 }
libc_hidden_def(__res_nclose)126 libc_hidden_def (__res_nclose)
127 
128 /* This is called when a thread is exiting to free resources held in _res.  */
129 void
130 __res_thread_freeres (void)
131 {
132   __resolv_context_freeres ();
133 
134   if (_res.nscount == 0)
135     /* Never called res_ninit.  */
136     return;
137 
138   __res_iclose (&_res, true);           /* Close any VC sockets.  */
139 
140   /* Make sure we do a full re-initialization the next time.  */
141   _res.options = 0;
142 }
143 /* Also must be called when the main thread exits.  */
144 text_set_element (__libc_subfreeres, __res_thread_freeres);
145