1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
|
/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
/* e-host-utils.c
*
* Copyright (C) 2001 Ximian, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Author: Chris Toshok
*/
#include <config.h>
#include <glib.h>
#include "e-host-utils.h"
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
G_LOCK_DEFINE_STATIC (gethost_mutex);
/**
* e_gethostbyname_r:
* @name: the host to resolve
* @host: a buffer pointing to a struct hostent to use for storage
* @buf: a buffer to use for hostname storage
* @buflen: the size of @buf
* @herr: a pointer to a variable to store an error code in
*
* Resolves the hostname @name, in a hopefully-reentrant fashion.
*
* Return value: 0 on success, ERANGE if @buflen is too small,
* "something else" otherwise (in which case *@herr will be set to
* one of the gethostbyname() error codes).
**/
int
e_gethostbyname_r (const char *name, struct hostent *host,
char *buf, int buflen, int *herr)
{
#ifdef HAVE_GETHOSTBYNAME_R
#ifdef GETHOSTBYNAME_R_FIVE_ARGS
if (gethostbyname_r(name, host, buf, buflen, herr))
return 0;
else
return errno;
#else
struct hostent *hp;
int retval;
retval = gethostbyname_r(name, host, buf, buflen, &hp, herr);
if (hp != NULL)
*herr = 0;
return retval;
#endif
#else
int i;
char *p;
struct hostent *h;
int req_length;
int num_aliases = 0, num_addrs = 0;
G_LOCK (gethost_mutex);
h = gethostbyname (name);
if (!h) {
*herr = h_errno;
G_UNLOCK (gethost_mutex);
return -1;
}
/* check to make sure we have enough room in our buffer */
req_length = 0;
if (h->h_aliases) {
for (i = 0; h->h_aliases[i]; i ++)
req_length += strlen (h->h_aliases[i]) + 1;
num_aliases = i;
}
if (h->h_addr_list) {
for (i = 0; h->h_addr_list[i]; i ++)
req_length += h->h_length;
num_addrs = i;
}
req_length += sizeof (char*) * (num_aliases + 1);
req_length += sizeof (char*) * (num_addrs + 1);
req_length += strlen (h->h_name) + 1;
if (buflen < req_length) {
*herr = ERANGE;
G_UNLOCK (gethost_mutex);
return ERANGE;
}
/* we store the alias/addr pointers in the buffer - figure out
their addresses here. */
p = buf;
if (num_aliases) {
host->h_aliases = (char**)p;
p += sizeof (char*) * (num_aliases + 1);
}
else
host->h_aliases = NULL;
if (num_addrs) {
host->h_addr_list = (char**)p;
p += sizeof(char*) * (num_addrs + 1);
}
else
host->h_addr_list = NULL;
/* copy the host name into the buffer */
host->h_name = p;
strcpy (p, h->h_name);
p += strlen (h->h_name) + 1;
host->h_addrtype = h->h_addrtype;
host->h_length = h->h_length;
/* copy the aliases/addresses into the buffer, and assign the
pointers into the hostent */
*p = 0;
if (num_aliases) {
for (i = 0; i < num_aliases; i ++) {
strcpy (p, h->h_aliases[i]);
host->h_aliases[i] = p;
p += strlen (h->h_aliases[i]);
}
host->h_aliases[num_aliases] = NULL;
}
if (num_addrs) {
for (i = 0; i < num_addrs; i ++) {
memcpy (p, h->h_addr_list[i], h->h_length);
host->h_addr_list[i] = p;
p += h->h_length;
}
host->h_addr_list[num_addrs] = NULL;
}
G_UNLOCK (gethost_mutex);
return 0;
#endif
}
|
