mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-18 19:10:06 +00:00
0c34b1e9b5
1999-10-30 Ulrich Drepper <drepper@cygnus.com> * manual/time.texi (Formatting Date and Time): Revise comments about origins of the formats with ISO C99 references. 1999-10-30 Andreas Jaeger <aj@suse.de> * sysdeps/unix/sysv/linux/ifreq.h: New file. 1999-10-29 Andreas Jaeger <aj@suse.de> * manual/arith.texi (Parsing of Floats): Document the hexadecimal input format; mention that strtof and strtold are part of ISO C99.
104 lines
2.5 KiB
C
104 lines
2.5 KiB
C
/* Copyright (C) 1999 Free Software Foundation, Inc.
|
|
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 Library General Public License as
|
|
published by the Free Software Foundation; either version 2 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
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. 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>
|
|
#include "kernel-features.h"
|
|
|
|
/* Variable to signal whether SIOCGIFCONF is not available. */
|
|
#if __ASSUME_SIOCGIFNAME == 0
|
|
static int old_siocgifconf;
|
|
#else
|
|
# define old_siocgifconf 0
|
|
#endif
|
|
|
|
|
|
static inline void
|
|
__ifreq (struct ifreq **ifreqs, int *num_ifs)
|
|
{
|
|
int fd = __opensock ();
|
|
struct ifconf ifc;
|
|
int rq_len;
|
|
int nifs;
|
|
# define RQ_IFS 4
|
|
|
|
if (fd < 0)
|
|
{
|
|
*num_ifs = 0;
|
|
*ifreqs = NULL;
|
|
return;
|
|
}
|
|
|
|
ifc.ifc_buf = NULL;
|
|
|
|
/* We may be able to get the needed buffer size directly, rather than
|
|
guessing. */
|
|
if (! old_siocgifconf)
|
|
{
|
|
ifc.ifc_buf = NULL;
|
|
ifc.ifc_len = 0;
|
|
if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0 || ifc.ifc_len == 0)
|
|
{
|
|
# if __ASSUME_SIOCGIFNAME == 0
|
|
old_siocgifconf = 1;
|
|
# endif
|
|
rq_len = RQ_IFS * sizeof (struct ifreq);
|
|
}
|
|
else
|
|
rq_len = ifc.ifc_len;
|
|
}
|
|
else
|
|
rq_len = RQ_IFS * sizeof (struct ifreq);
|
|
|
|
/* Read all the interfaces out of the kernel. */
|
|
do
|
|
{
|
|
ifc.ifc_len = rq_len;
|
|
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);
|
|
|
|
__close (fd);
|
|
|
|
*num_ifs = 0;
|
|
*ifreqs = NULL;
|
|
return;
|
|
}
|
|
rq_len *= 2;
|
|
}
|
|
while (ifc.ifc_len == rq_len && old_siocgifconf);
|
|
|
|
nifs = ifc.ifc_len / sizeof (struct ifreq);
|
|
__close (fd);
|
|
|
|
*num_ifs = nifs;
|
|
*ifreqs = realloc (ifc.ifc_buf, nifs * sizeof (struct ifreq));
|
|
}
|
|
|
|
static inline void
|
|
__if_freereq (struct ifreq *ifreqs)
|
|
{
|
|
free (ifreqs);
|
|
}
|