Add UDP discovery configuration for the STM3240G-EVAL (from Max Holtzberg)

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@5138 7fd9a85b-ad96-42d3-883c-3090e2eb8679

nuttx/tools/README.txt

@@ -17,6 +17,12 @@ configure.sh
   target board.  See configs/README.txt or Documentation/NuttxPortingGuide.html
   for a description of how to configure NuttX with this script.
 
+discover.py
+
+  Example script for discovering devices in the local network.
+  It is the counter part to apps/netutils/discover
+
+
 mkconfig.c, cfgparser.c, and cfgparser.h
 
   These are Cs file that are used to build mkconfig program.  The mkconfig

nuttx/tools/discover.py

@@ -0,0 +1,98 @@
+#!/usr/bin/env python
+############################################################################
+# tools/indent.sh
+#
+#   Copyright (C) 2012 Max Holtzberg. All rights reserved.
+#   Author: Max Holtzberg <mh@uvc.de>
+#
+# 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.
+#
+############################################################################
+
+import array
+import time
+from socket import *
+
+PORT = 96
+
+DISCOVER_PROTO_ID = 0x99
+DISCOVER_ALL = 0xff         # 0xff means all devices
+DISCOVER_REQUEST = 0x01
+DISCOVER_RESPONSE = 0x02
+DISCOVER_REQUEST_SIZE = 4
+DISCOVER_RESPONSE_SIZE = 35
+
+def check_sum(data):
+    chksum = 0
+    for c in data[:-1]:
+        chksum -= c
+    return (chksum & 0xff) == data[-1]
+
+def send_discover(socket):
+    cmd = array.array('B', [0] * DISCOVER_REQUEST_SIZE)
+    cmd[0] = DISCOVER_PROTO_ID # Tag for identification of the protocol
+    cmd[1] = DISCOVER_REQUEST  # Request command
+    cmd[2] = DISCOVER_ALL
+    chksum = 0
+    for c in cmd[:3]:
+        chksum -= c;
+    cmd[3] = chksum & 0xff
+    
+    socket.sendto(cmd, ('<broadcast>', PORT))
+
+def read_responses(socket):
+    res = []
+    response = array.array('B', [0] * DISCOVER_RESPONSE_SIZE)
+    try:
+        while 1:
+            size, src = socket.recvfrom_into(response)
+            if (size == DISCOVER_RESPONSE_SIZE
+                and response[0] == DISCOVER_PROTO_ID
+                and response[1] == DISCOVER_RESPONSE
+                and check_sum(response)):
+                
+                dev = {}
+                dev['addr'] = src[0]
+                dev['descr'] = response[2:-1].tostring().rstrip('\0')
+                res.append(dev)
+
+    except timeout:
+        return res
+
+if __name__ == '__main__':
+    print 'Sending discover...'
+
+    s = socket(AF_INET, SOCK_DGRAM)
+    s.bind(('0.0.0.0', PORT))
+    s.setsockopt(SOL_SOCKET, SO_BROADCAST, 1)
+    s.settimeout(1.0);
+    send_discover(s)
+    devices = read_responses(s)
+    socket.close(s)
+
+    print devices