Add support so that fdopen() may be used on socket descriptors

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3659 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 88 insertions, 0 deletions

diff --git a/nuttx/net/net_checksd.c b/nuttx/net/net_checksd.c
new file mode 100644
index 000000000..76d30fbee
--- /dev/null
+++ b/nuttx/net/net_checksd.c
@@ -0,0 +1,88 @@
+/****************************************************************************
+ * net/net_checksd.c
+ *
+ *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * 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 <sys/socket.h>
+
+#include <sched.h>
+#include <errno.h>
+#include <debug.h>
+
+#include "net_internal.h"
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: net_checksd
+ *
+ * Description:
+ *   Check if the socket descriptor is valid for the provided TCB and if it
+ *   supports the requested access.  This trivial operation is part of the
+ *   fdopen() operation when the fdopen() is performed on a socket descriptor.
+ *   It simply performs some sanity checking before permitting the socket
+ *   descriptor to be wrapped as a C FILE stream.
+ *
+ ****************************************************************************/
+
+#if defined(CONFIG_NET) && CONFIG_NFILE_DESCRIPTORS > 0
+int net_checksd(FAR _TCB *tcb, int sd, int oflags)
+{
+  FAR struct socket *psock = sockfd_socket(sd);
+
+  /* Verify that the sockfd corresponds to valid, allocated socket */
+
+  if (!psock || psock->s_crefs <= 0)
+    {
+      nvdbg("No valid socket for sd: %d\n", sd);
+      return -EBADF;
+    }
+
+  /* NOTE:  We permit the socket FD to be "wrapped" in a stream as
+   * soon as the socket descriptor is created by socket().  Therefore
+   * (1) we don't care if the socket is connected yet, and (2) there
+   * are no access restrictions that can be enforced yet.
+   */
+
+  return OK;
+}
+#endif /* CONIG_NET && ONFIG_NFILE_DESCRIPTORS > 0 */
+