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-rw-r--r--libc/inet/if_nametoindex.c171
1 files changed, 149 insertions, 22 deletions
diff --git a/libc/inet/if_nametoindex.c b/libc/inet/if_nametoindex.c
index 40818aad9..a697419b6 100644
--- a/libc/inet/if_nametoindex.c
+++ b/libc/inet/if_nametoindex.c
@@ -1,40 +1,167 @@
-/*
+/* Copyright (C) 1997,98,99,2000,02 Free Software Foundation, Inc.
+ * This file is part of the GNU C Library.
+ *
+ * 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.
*
- * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>,
- * The Silver Hammer Group, Ltd.
+ * 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.
*
- * This 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.
+ * 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.
*
+ * Reworked Dec 2002 by Erik Andersen <andersen@codepoet.org>
*/
+
#define __FORCE_GLIBC
#include <features.h>
+#include <string.h>
+#include <errno.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <unistd.h>
+#include <stdlib.h>
-unsigned int if_nametoindex(const char* blub) {
- struct ifreq ifr;
- int fd;
- char *tmp;
- int len=sizeof(ifr.ifr_name);
-
+static int __opensock(void)
+{
+ int fd;
#ifdef __UCLIBC_HAS_IPV6__
- fd=socket(AF_INET6,SOCK_DGRAM,0);
- if (fd<0)
+ fd=socket(AF_INET6,SOCK_DGRAM,0);
+ if (fd<0)
#endif /* __UCLIBC_HAS_IPV6__ */
- fd=socket(AF_INET,SOCK_DGRAM,0);
+ fd=socket(AF_INET,SOCK_DGRAM,0);
+ return(fd);
+}
+
+unsigned int if_nametoindex(const char* ifname)
+{
+#ifndef SIOCGIFINDEX
+ __set_errno (ENOSYS);
+ return 0;
+#else
+ int fd;
+ struct ifreq ifr;
- for (tmp=ifr.ifr_name; len>0; --len) {
- if ((*tmp++ = *blub++)==0) break;
+ fd = __opensock();
+ if (fd < 0)
+ return 0;
+ strncpy (ifr.ifr_name, ifname, sizeof (ifr.ifr_name));
+ if (ioctl(fd,SIOCGIFINDEX,&ifr) < 0) {
+ int saved_errno = errno;
+ close(fd);
+ if (saved_errno == EINVAL)
+ __set_errno(ENOSYS);
+ return 0;
+ }
+ close(fd);
+ return ifr.ifr_ifindex;
+
+#endif /* SIOCGIFINDEX */
+}
+
+void if_freenameindex (struct if_nameindex *ifn)
+{
+ struct if_nameindex *ptr = ifn;
+ while (ptr->if_name || ptr->if_index) {
+ if (ptr->if_name) {
+ free (ptr->if_name);
}
+ ++ptr;
+ }
+ free (ifn);
+}
+
+struct if_nameindex * if_nameindex (void)
+{
+#ifndef SIOCGIFINDEX
+ __set_errno (ENOSYS);
+ return NULL;
+#else
+ int fd;
+ struct ifconf ifc;
+ unsigned int nifs, i;
+ int rq_len;
+ struct if_nameindex *idx = NULL;
+# define RQ_IFS 4
+
+ fd = __opensock();
+ if (fd < 0)
+ return 0;
+
+ ifc.ifc_buf = NULL;
- if (ioctl(fd,SIOCGIFINDEX,&ifr)==0) {
- close(fd);
- return ifr.ifr_ifindex;
+ /* Guess on the correct buffer size... */
+ rq_len = RQ_IFS * sizeof (struct ifreq);
+
+ /* Read all the interfaces out of the kernel. */
+ do {
+ ifc.ifc_buf = realloc(ifc.ifc_buf, ifc.ifc_len = rq_len);
+ if (ifc.ifc_buf == NULL || ioctl(fd, SIOCGIFCONF, &ifc) < 0) {
+ close(fd);
+ return NULL;
}
+ rq_len *= 2;
+ } while (ifc.ifc_len == rq_len);
+
+ nifs = ifc.ifc_len / sizeof(struct ifreq);
+
+ idx = malloc ((nifs + 1) * sizeof(struct if_nameindex));
+ if (idx == NULL) {
close(fd);
- return 0;
+ __set_errno(ENOBUFS);
+ return NULL;
+ }
+
+ for (i = 0; i < nifs; ++i) {
+ struct ifreq *ifr = &ifc.ifc_req[i];
+ idx[i].if_name = strdup (ifr->ifr_name);
+ if (idx[i].if_name == NULL || ioctl(fd,SIOCGIFINDEX,ifr) < 0) {
+ int saved_errno = errno;
+ unsigned int j;
+ for (j = 0; j < i; ++j)
+ free (idx[j].if_name);
+ free(idx);
+ close(fd);
+ if (saved_errno == EINVAL)
+ saved_errno = ENOSYS;
+ else if (saved_errno == ENOMEM)
+ saved_errno = ENOBUFS;
+ __set_errno (saved_errno);
+ return NULL;
+ }
+ idx[i].if_index = ifr->ifr_ifindex;
+ }
+
+ idx[i].if_index = 0;
+ idx[i].if_name = NULL;
+
+ close(fd);
+ return idx;
+#endif
}
+
+char * if_indextoname (unsigned int ifindex, char *ifname)
+{
+ struct if_nameindex *idx;
+ struct if_nameindex *p;
+ char *result = NULL;
+
+ idx = if_nameindex();
+ if (idx != NULL) {
+ for (p = idx; p->if_index || p->if_name; ++p) {
+ if (p->if_index == ifindex) {
+ result = strncpy (ifname, p->if_name, IFNAMSIZ);
+ break;
+ }
+ }
+ if_freenameindex (idx);
+ }
+ return result;
+}
+