xref: /titanic_41/usr/src/lib/libresolv2/common/irs/irs_data.c (revision d24234c24aeaca4ca56ee3ac2794507968f274c4)
1 /*
2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (c) 1996,1999 by Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #if !defined(LINT) && !defined(CODECENTER)
19 static const char rcsid[] = "$Id: irs_data.c,v 1.12 2007/08/27 03:32:26 marka Exp $";
20 #endif
21 
22 #include "port_before.h"
23 
24 #ifndef __BIND_NOSTATIC
25 
26 #include <sys/types.h>
27 
28 #include <netinet/in.h>
29 #include <arpa/nameser.h>
30 
31 #include <resolv.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <isc/memcluster.h>
35 
36 #ifdef DO_PTHREADS
37 #include <pthread.h>
38 #endif
39 
40 #include <irs.h>
41 #include <stdlib.h>
42 
43 #include "port_after.h"
44 
45 #include "irs_data.h"
46 #undef _res
47 #if !(__GLIBC__ > 2 || __GLIBC__ == 2 &&  __GLIBC_MINOR__ >= 3)
48 #undef h_errno
49 extern int h_errno;
50 #endif
51 
52 extern struct __res_state _res;
53 
54 #ifdef	DO_PTHREADS
55 static pthread_key_t	key;
56 static int		once = 0;
57 #else
58 static struct net_data	*net_data;
59 #endif
60 
61 void
62 irs_destroy(void) {
63 #ifndef DO_PTHREADS
64 	if (net_data != NULL)
65 		net_data_destroy(net_data);
66 	net_data = NULL;
67 #endif
68 }
69 
70 void
71 net_data_destroy(void *p) {
72 	struct net_data *net_data = p;
73 
74 	res_ndestroy(net_data->res);
75 	if (net_data->gr != NULL) {
76 		(*net_data->gr->close)(net_data->gr);
77 		net_data->gr = NULL;
78 	}
79 	if (net_data->pw != NULL) {
80 		(*net_data->pw->close)(net_data->pw);
81 		net_data->pw = NULL;
82 	}
83 	if (net_data->sv != NULL) {
84 		(*net_data->sv->close)(net_data->sv);
85 		net_data->sv = NULL;
86 	}
87 	if (net_data->pr != NULL) {
88 		(*net_data->pr->close)(net_data->pr);
89 		net_data->pr = NULL;
90 	}
91 	if (net_data->ho != NULL) {
92 		(*net_data->ho->close)(net_data->ho);
93 		net_data->ho = NULL;
94 	}
95 	if (net_data->nw != NULL) {
96 		(*net_data->nw->close)(net_data->nw);
97 		net_data->nw = NULL;
98 	}
99 	if (net_data->ng != NULL) {
100 		(*net_data->ng->close)(net_data->ng);
101 		net_data->ng = NULL;
102 	}
103 	if (net_data->ho_data != NULL) {
104 		free(net_data->ho_data);
105 		net_data->ho_data = NULL;
106 	}
107 	if (net_data->nw_data != NULL) {
108 		free(net_data->nw_data);
109 		net_data->nw_data = NULL;
110 	}
111 
112 	(*net_data->irs->close)(net_data->irs);
113 	memput(net_data, sizeof *net_data);
114 }
115 
116 /*%
117  *  applications that need a specific config file other than
118  * _PATH_IRS_CONF should call net_data_init directly rather than letting
119  *   the various wrapper functions make the first call. - brister
120  */
121 
122 struct net_data *
123 net_data_init(const char *conf_file) {
124 #ifdef	DO_PTHREADS
125 #ifndef LIBBIND_MUTEX_INITIALIZER
126 #define LIBBIND_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
127 #endif
128 	static pthread_mutex_t keylock = LIBBIND_MUTEX_INITIALIZER;
129 	struct net_data *net_data;
130 
131 	if (!once) {
132 		if (pthread_mutex_lock(&keylock) != 0)
133 			return (NULL);
134 		if (!once) {
135 			if (pthread_key_create(&key, net_data_destroy) != 0) {
136 				(void)pthread_mutex_unlock(&keylock);
137 				return (NULL);
138 			}
139 			once = 1;
140 		}
141 		if (pthread_mutex_unlock(&keylock) != 0)
142 			return (NULL);
143 	}
144 	net_data = pthread_getspecific(key);
145 #endif
146 
147 	if (net_data == NULL) {
148 		net_data = net_data_create(conf_file);
149 		if (net_data == NULL)
150 			return (NULL);
151 #ifdef	DO_PTHREADS
152 		if (pthread_setspecific(key, net_data) != 0) {
153 			net_data_destroy(net_data);
154 			return (NULL);
155 		}
156 #endif
157 	}
158 
159 	return (net_data);
160 }
161 
162 struct net_data *
163 net_data_create(const char *conf_file) {
164 	struct net_data *net_data;
165 
166 	net_data = memget(sizeof (struct net_data));
167 	if (net_data == NULL)
168 		return (NULL);
169 	memset(net_data, 0, sizeof (struct net_data));
170 
171 	if ((net_data->irs = irs_gen_acc("", conf_file)) == NULL) {
172 		memput(net_data, sizeof (struct net_data));
173 		return (NULL);
174 	}
175 #ifndef DO_PTHREADS
176 	(*net_data->irs->res_set)(net_data->irs, &_res, NULL);
177 #endif
178 
179 	net_data->res = (*net_data->irs->res_get)(net_data->irs);
180 	if (net_data->res == NULL) {
181 		(*net_data->irs->close)(net_data->irs);
182 		memput(net_data, sizeof (struct net_data));
183 		return (NULL);
184 	}
185 
186 	if ((net_data->res->options & RES_INIT) == 0U &&
187 	    res_ninit(net_data->res) == -1) {
188 		(*net_data->irs->close)(net_data->irs);
189 		memput(net_data, sizeof (struct net_data));
190 		return (NULL);
191 	}
192 
193 	return (net_data);
194 }
195 
196 void
197 net_data_minimize(struct net_data *net_data) {
198 	res_nclose(net_data->res);
199 }
200 
201 #ifdef _REENTRANT
202 struct __res_state *
203 __res_state(void) {
204 	/* NULL param here means use the default config file. */
205 	struct net_data *net_data = net_data_init(NULL);
206 	if (net_data && net_data->res)
207 		return (net_data->res);
208 
209 	return (&_res);
210 }
211 #else
212 #ifdef __linux
213 struct __res_state *
214 __res_state(void) {
215 	return (&_res);
216 }
217 #endif
218 #endif
219 
220 int *
221 __h_errno(void) {
222 	/* NULL param here means use the default config file. */
223 	struct net_data *net_data = net_data_init(NULL);
224 	if (net_data && net_data->res)
225 		return (&net_data->res->res_h_errno);
226 #if !(__GLIBC__ > 2 || __GLIBC__ == 2 &&  __GLIBC_MINOR__ >= 3)
227 	return(&_res.res_h_errno);
228 #else
229 	return (&h_errno);
230 #endif
231 }
232 
233 void
234 __h_errno_set(struct __res_state *res, int err) {
235 
236 
237 #if (__GLIBC__ > 2 || __GLIBC__ == 2 &&  __GLIBC_MINOR__ >= 3)
238 	res->res_h_errno = err;
239 #else
240 	h_errno = res->res_h_errno = err;
241 #endif
242 }
243 
244 #endif /*__BIND_NOSTATIC*/
245 
246 /*! \file */
247