← Back to branch summary

~mysql/mysql-server/mysql-6.0

« back to all changes in this revision

Viewing changes to mit-pthreads/net/gethostbyaddr.c

  • Committer: bk at mysql
  • Date: 2000-07-31 19:29:14 UTC
  • Revision ID: sp1r-bk@work.mysql.com-20000731192914-08846
Import changeset

Show diffs side-by-side

added added

removed removed

Lines of Context:
mit-pthreads/net/gethostbyaddr.c
 
1
/*
 
2
 * Copyright (c) 1985, 1988 Regents of the University of California.
 
3
 * All rights reserved.
 
4
 *
 
5
 * Redistribution and use in source and binary forms, with or without
 
6
 * modification, are permitted provided that the following conditions
 
7
 * are met:
 
8
 * 1. Redistributions of source code must retain the above copyright
 
9
 *        notice, this list of conditions and the following disclaimer.
 
10
 * 2. Redistributions in binary form must reproduce the above copyright
 
11
 *        notice, this list of conditions and the following disclaimer in the
 
12
 *        documentation and/or other materials provided with the distribution.
 
13
 * 3. All advertising materials mentioning features or use of this software
 
14
 *        must display the following acknowledgement:
 
15
 *      This product includes software developed by the University of
 
16
 *      California, Berkeley and its contributors.
 
17
 * 4. Neither the name of the University nor the names of its contributors
 
18
 *        may be used to endorse or promote products derived from this software
 
19
 *        without specific prior written permission.
 
20
 *
 
21
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 
22
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 
23
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 
24
 * ARE DISCLAIMED.      IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 
25
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 
26
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 
27
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 
28
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 
29
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 
30
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 
31
 * SUCH DAMAGE.
 
32
 */
 
33
 
 
34
#if defined(LIBC_SCCS) && !defined(lint)
 
35
/*static char *sccsid = "from: @(#)gethostbyaddr.c      6.45 (Berkeley) 2/24/91";*/
 
36
static char *rcsid = "$Id$";
 
37
#endif /* LIBC_SCCS and not lint */
 
38
 
 
39
 
 
40
#include <pthread.h>
 
41
#include <stdio.h>
 
42
#include <string.h>
 
43
#include <stdlib.h>
 
44
#include <netdb.h>
 
45
#include <netinet/in.h>
 
46
#include <resolv.h>
 
47
#include <netinet/in.h>
 
48
#include <errno.h>
 
49
#include <sys/socket.h>
 
50
#include "res_internal.h"
 
51
 
 
52
static struct hostent *file_find_addr(const char *addr, int len, int type,
 
53
                                                                          struct hostent *result, char *buf,
 
54
                                                                          int bufsize, int *errval);
 
55
 
 
56
struct hostent *gethostbyaddr(const char *addr, int len, int type)
 
57
{
 
58
        struct res_data *data = _res_init();
 
59
 
 
60
        if (!data)
 
61
                return NULL;
 
62
        if (!data->buf) {
 
63
                data->buf = malloc(sizeof(struct hostent) + HOST_BUFSIZE);
 
64
                if (!data->buf) {
 
65
                        errno = 0;
 
66
                        data->errval = NO_RECOVERY;
 
67
                        return NULL;
 
68
                }
 
69
        }
 
70
        return gethostbyaddr_r(addr, len, type, (struct hostent *) data->buf,
 
71
                                                   data->buf + sizeof(struct hostent), HOST_BUFSIZE,
 
72
                                                   &data->errval);
 
73
}
 
74
 
 
75
struct hostent *gethostbyaddr_r(const char *addr, int len, int type,
 
76
                                                                struct hostent *result, char *buf, int bufsize,
 
77
                                                                int *errval)
 
78
{
 
79
        struct res_data *data;
 
80
        querybuf qbuf;
 
81
        char lookups[MAXDNSLUS], addrbuf[MAXDNAME], *abuf;
 
82
        struct hostent *hp;
 
83
        int n, i;
 
84
 
 
85
        /* Default failure condition is not a range error and not recoverable. */
 
86
        errno = 0;
 
87
        *errval = NO_RECOVERY;
 
88
        
 
89
        data = _res_init();
 
90
        if (!data)
 
91
                return NULL;
 
92
 
 
93
        if (type != AF_INET)
 
94
                return NULL;
 
95
        sprintf(addrbuf, "%u.%u.%u.%u.in-addr.arpa",
 
96
                        (unsigned)addr[3] & 0xff, (unsigned)addr[2] & 0xff,
 
97
                        (unsigned)addr[1] & 0xff, (unsigned)addr[0] & 0xff);
 
98
 
 
99
        memcpy(lookups, data->state.lookups, sizeof(lookups));
 
100
        if (*lookups == 0)
 
101
                strncpy(lookups, "bf", sizeof(lookups));
 
102
 
 
103
        hp = NULL;
 
104
        for (i = 0; i < MAXDNSLUS && hp == NULL && lookups[i]; i++) {
 
105
                switch (lookups[i]) {
 
106
                  case  'b':
 
107
 
 
108
                        /* Allocate space for a one-item list of addresses. */
 
109
                        abuf = SP(SP(buf, char *, 2), struct in_addr, 1);
 
110
                        if (abuf > buf + bufsize) {
 
111
                                errno = ERANGE;
 
112
                                return NULL;
 
113
                        }
 
114
 
 
115
                        /* Perform and parse the query. */
 
116
                        n = res_query(addrbuf, C_IN, T_PTR, (char *)&qbuf, sizeof(qbuf));
 
117
                        if (n < 0)
 
118
                                break;
 
119
                        hp = _res_parse_answer(&qbuf, n, 1, result, abuf,
 
120
                                                                   bufsize - (abuf - buf), errval);
 
121
                        if (hp == NULL)
 
122
                                break;
 
123
 
 
124
                        /* Fill in our own address list. */
 
125
                        result->h_addrtype = type;
 
126
                        result->h_length = len;
 
127
                        result->h_addr_list = (char **) ALIGN(buf, char *);
 
128
                        result->h_addr_list[0] = ALIGN(&result->h_addr_list[2],
 
129
                                                                                   struct in_addr);
 
130
                        result->h_addr_list[1] = NULL;
 
131
                        break;
 
132
 
 
133
                  case 'f':
 
134
                        hp = file_find_addr(addr, len, type, result, buf, bufsize, errval);
 
135
                        break;
 
136
                }
 
137
        }
 
138
 
 
139
        return hp;
 
140
}
 
141
 
 
142
static struct hostent *file_find_addr(const char *addr, int len, int type,
 
143
                                                                          struct hostent *result, char *buf,
 
144
                                                                          int bufsize, int *errval)
 
145
{
 
146
        FILE *fp = NULL;
 
147
 
 
148
        pthread_mutex_lock(&host_iterate_lock);
 
149
        sethostent(0);
 
150
        while ((result = gethostent_r(result, buf, bufsize, errval)) != NULL) {
 
151
                /* Check the entry against the given address. */
 
152
                if (result->h_addrtype == type &&
 
153
                        memcmp(result->h_addr, addr, len) == 0)
 
154
                        break;
 
155
        }
 
156
        pthread_mutex_unlock(&host_iterate_lock);
 
157
        if (!result && errno != ERANGE)
 
158
                *errval = HOST_NOT_FOUND;
 
159
        return result;
 
160
}
 
161