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-rw-r--r--inet/ifreq.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/inet/ifreq.c b/inet/ifreq.c
new file mode 100644
index 0000000000..55e833bdb3
--- /dev/null
+++ b/inet/ifreq.c
@@ -0,0 +1,80 @@
+/* Copyright (C) 1999, 2002, 2003, 2004 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 "ifreq.h"
+
+
+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;
+ void *newp = realloc (ifc.ifc_buf, ifc.ifc_len);
+ if (newp == NULL || __ioctl (fd, SIOCGIFCONF, &ifc) < 0)
+ {
+ free (ifc.ifc_buf);
+
+ if (fd != sockfd)
+ __close (fd);
+ *num_ifs = 0;
+ *ifreqs = NULL;
+ return;
+ }
+ ifc.ifc_buf = newp;
+ }
+ 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));
+}