From fa8b7c19b786f8e46319e79304a91dd51d2892a6 Mon Sep 17 00:00:00 2001
From: Gregory Nutt <gnutt@nuttx.org>
Date: Fri, 29 May 2015 11:03:02 -0600
Subject: [PATCH] Forgot to add a file in the last commit

---
 net/netdev/netdev_verify.c | 80 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)
 create mode 100644 net/netdev/netdev_verify.c

diff --git a/net/netdev/netdev_verify.c b/net/netdev/netdev_verify.c
new file mode 100644
index 0000000000..67f8ae4149
--- /dev/null
+++ b/net/netdev/netdev_verify.c
@@ -0,0 +1,80 @@
+/****************************************************************************
+ * net/netdev/netdev_verify.c
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdbool.h>
+
+#include <nuttx/net/netdev.h>
+
+#include "netdev/netdev.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function: netdev_verify
+ *
+ * Description:
+ *   Verify that the specified device still exists
+ *
+ * Assumptions:
+ *   The caller has locked the network.
+ *
+ ****************************************************************************/
+
+bool netdev_verify(FAR struct net_driver_s *dev)
+{
+  FAR struct net_driver_s *chkdev;
+  bool valid = false;
+
+  netdev_semtake();
+  for (chkdev = g_netdevices; chkdev != NULL; chkdev = chkdev->flink)
+    {
+      if (chkdev == dev)
+        {
+          valid = true;
+          break;
+        }
+    }
+
+  netdev_semgive();
+  return valid;
+}