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
|
/* Copyright (C) 1999,2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Jaeger <aj@suse.de>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <net/if.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
static inline struct ifreq *
__if_nextreq (struct ifreq *ifr)
{
#ifdef _HAVE_SA_LEN
if (ifr->ifa_addr > sizeof ifr->ifa_addr)
return (struct ifreq *) ((char *) &ifr->ifa_addr + ifr->ifa_addr.sa_len);
#endif
return ifr + 1;
}
static inline void
__ifreq (struct ifreq **ifreqs, int *num_ifs, int sockfd)
{
int fd = sockfd;
struct ifconf ifc;
int rq_len;
int nifs;
# define RQ_IFS 4
if (fd < 0)
fd = __opensock ();
if (fd < 0)
{
*num_ifs = 0;
*ifreqs = NULL;
return;
}
ifc.ifc_buf = NULL;
rq_len = RQ_IFS * sizeof (struct ifreq) / 2; /* Doubled in the loop. */
do
{
ifc.ifc_len = rq_len *= 2;
ifc.ifc_buf = realloc (ifc.ifc_buf, ifc.ifc_len);
if (ifc.ifc_buf == NULL || __ioctl (fd, SIOCGIFCONF, &ifc) < 0)
{
if (ifc.ifc_buf)
free (ifc.ifc_buf);
if (fd != sockfd)
__close (fd);
*num_ifs = 0;
*ifreqs = NULL;
return;
}
}
while (rq_len < sizeof (struct ifreq) + ifc.ifc_len);
if (fd != sockfd)
__close (fd);
#ifdef _HAVE_SA_LEN
struct ifreq *ifr = ifreqs;
nifs = 0;
while ((char *) ifr < ifc.ifc_buf + ifc.ifc_len)
{
++nifs;
ifr = __if_nextreq (ifr);
if (ifr == NULL)
break;
}
#else
nifs = ifc.ifc_len / sizeof (struct ifreq);
#endif
*num_ifs = nifs;
*ifreqs = realloc (ifc.ifc_buf, nifs * sizeof (struct ifreq));
}
static inline void
__if_freereq (struct ifreq *ifreqs, int num_ifs)
{
free (ifreqs);
}
|
