sync with glibc

1 files changed, 218 insertions, 0 deletions

diff --git a/libc/inet/if_index.c b/libc/inet/if_index.c
new file mode 100644
index 000000000..5837faa65
--- /dev/null
+++ b/libc/inet/if_index.c
@@ -0,0 +1,218 @@
+/* Copyright (C) 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005
+   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.
+
+   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.
+
+   Reworked Dec 2002 by Erik Andersen <andersen@codepoet.org>
+ */
+
+#define strndup __strndup
+
+#define __FORCE_GLIBC
+#include <features.h>
+#define __USE_GNU
+#include <string.h>
+#include <alloca.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <net/if.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <libc-internal.h>
+
+extern int __opensock(void) attribute_hidden;
+
+unsigned int
+if_nametoindex(const char* ifname) 
+{
+#ifndef SIOCGIFINDEX
+  __set_errno (ENOSYS);
+  return 0;
+#else
+  struct ifreq ifr;
+  int 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
+}
+
+void
+if_freenameindex (struct if_nameindex *ifn)
+{
+  struct if_nameindex *ptr = ifn;
+  while (ptr->if_name || ptr->if_index)
+    {
+      free (ptr->if_name);
+      ++ptr;
+    }
+  free (ifn);
+}
+
+struct if_nameindex *
+if_nameindex (void)
+{
+#ifndef SIOCGIFINDEX
+  __set_errno (ENOSYS);
+  return NULL;
+#else
+  int fd = __opensock ();
+  struct ifconf ifc;
+  unsigned int nifs, i;
+  int rq_len;
+  struct if_nameindex *idx = NULL;
+# define RQ_IFS	4
+
+  if (fd < 0)
+    return NULL;
+
+  ifc.ifc_buf = NULL;
+
+  /* Guess on the correct buffer size... */
+  rq_len = RQ_IFS * sizeof (struct ifreq);
+
+  /* Read all the interfaces out of the kernel.  */
+  ifc.ifc_buf = alloca (rq_len);
+  ifc.ifc_len = rq_len;
+  while (1)
+    {
+      if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0)
+	{
+	  __close (fd);
+	  return NULL;
+	}
+      if (ifc.ifc_len < rq_len)
+	break;
+
+      ifc.ifc_buf = extend_alloca (ifc.ifc_buf, rq_len, 2 * rq_len);
+      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);
+      __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)
+{
+#if !defined SIOCGIFINDEX
+  __set_errno (ENOSYS);
+  return NULL;
+#else
+# ifdef SIOCGIFNAME
+  /* Use ioctl to avoid searching the list. */
+  struct ifreq ifr;
+  int fd;
+
+  fd = __opensock ();
+
+  if (fd < 0)
+    return NULL;
+
+  ifr.ifr_ifindex = ifindex;
+  if (__ioctl (fd, SIOCGIFNAME, &ifr) < 0)
+    {
+      int serrno = errno;
+      __close (fd);
+      if (serrno == ENODEV)
+	/* POSIX requires ENXIO.  */
+	serrno = ENXIO;
+      __set_errno (serrno);
+      return NULL;
+  }
+  __close (fd);
+
+  return __strncpy (ifname, ifr.ifr_name, IFNAMSIZ);
+# else
+  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);
+
+      if (result == NULL)
+	__set_errno (ENXIO);
+    }
+  return result;
+# endif
+#endif
+}
+