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-rw-r--r--sysdeps/unix/sysv/linux/if_index.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/if_index.c b/sysdeps/unix/sysv/linux/if_index.c
new file mode 100644
index 0000000000..3f5a890a9c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/if_index.c
@@ -0,0 +1,140 @@
+/* Copyright (C) 1997 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 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., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <net/if.h>
+
+#define IF_INET6_FILENAME "/proc/net/if_inet6"
+
+/* /proc/net/if_inet6 contains lines that look like this:
+ *
+ * fe8000000000000000000000836fc168 0b 00 20 80 sit7
+ *
+ * | | | | | |
+ * address --' | | | | |
+ * index --------' | | | |
+ * prefix length ---' | | |
+ * scope --------------' | |
+ * flags -----------------' |
+ * name -------------------------'
+ *
+ */
+
+static int get_one_interface(FILE *fd, char *interface, int iflen, unsigned int *index)
+{
+ char buffer[80];
+ static char seps[] = " \012";
+ char *c = buffer;
+ char *sp;
+ if (!fgets(buffer, 80, fd))
+ return 1;
+ if (strtok_r(buffer, seps, &sp) == NULL) return 1;
+ if (c = strtok_r(NULL, seps, &sp), c == NULL) return 1;
+ *index = strtoul(c, NULL, 16);
+ if (strtok_r(NULL, seps, &sp) == NULL) return 1;
+ if (strtok_r(NULL, seps, &sp) == NULL) return 1;
+ if (strtok_r(NULL, seps, &sp) == NULL) return 1;
+ if (c = strtok_r(NULL, seps, &sp), c == NULL) return 1;
+ strncpy(interface, c, iflen);
+ return 0;
+}
+
+unsigned int if_nametoindex(const char *ifname)
+{
+ FILE *fd = fopen(IF_INET6_FILENAME, "r");
+ char this_ifname[IFNAMSIZ];
+ unsigned int this_index;
+ if (!fd) return 0;
+ while (get_one_interface(fd, this_ifname, IFNAMSIZ, &this_index) == 0) {
+ if (!strcmp(this_ifname, ifname)) {
+ fclose(fd);
+ return this_index;
+ }
+ }
+ fclose(fd);
+ return 0;
+}
+
+char *if_indextoname(unsigned int ifindex, char *ifname)
+{
+ FILE *fd = fopen(IF_INET6_FILENAME, "r");
+ unsigned int this_index;
+ if (!fd) return NULL;
+ while (get_one_interface(fd, ifname, IFNAMSIZ, &this_index) == 0) {
+ if (this_index == ifindex) {
+ fclose(fd);
+ return ifname;
+ }
+ }
+ fclose(fd);
+ return NULL;
+}
+
+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)
+{
+ FILE *fd = fopen(IF_INET6_FILENAME, "r");
+ struct if_nameindex *ifn = NULL;
+ int nifs = 0;
+ if (!fd) return NULL;
+ do
+ {
+ struct if_nameindex *newifn;
+ nifs++;
+ newifn = realloc(ifn, nifs*sizeof(struct if_nameindex));
+ if (!newifn)
+ {
+ /* We ran out of memory. */
+ if (--nifs)
+ {
+ free(ifn[nifs-1].if_name);
+ ifn[nifs-1].if_name = 0;
+ ifn[nifs-1].if_index = 0;
+ if_freenameindex(ifn);
+ }
+ return NULL;
+ }
+ ifn = newifn;
+ ifn[nifs-1].if_index = 0;
+ ifn[nifs-1].if_name = malloc(IFNAMSIZ);
+ if (ifn[nifs-1].if_name == NULL)
+ {
+ if_freenameindex(ifn);
+ return NULL;
+ }
+ }
+ while (get_one_interface(fd, ifn[nifs-1].if_name, IFNAMSIZ,
+ &ifn[nifs-1].if_index) == 0);
+ free(ifn[nifs-1].if_name);
+ ifn[nifs-1].if_name = NULL;
+ fclose(fd);
+ return ifn;
+}