1 files changed, 38 insertions, 0 deletions
diff --git a/gr-digital/python/crc.py b/gr-digital/python/crc.py
new file mode 100644
index 000000000..198ab059f
--- /dev/null
+++ b/gr-digital/python/crc.py
@@ -0,0 +1,38 @@
+#
+# Copyright 2005,2007,2011 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+# 
+# GNU Radio 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 General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
+
+from gnuradio import gru
+import digital_swig
+import struct
+
+def gen_and_append_crc32(s):
+    crc = digital_swig.crc32(s)
+    return s + struct.pack(">I", gru.hexint(crc) & 0xFFFFFFFF)
+
+def check_crc32(s):
+    if len(s) < 4:
+        return (False, '')
+    msg = s[:-4]
+    #print "msg = '%s'" % (msg,)
+    actual = digital_swig.crc32(msg)
+    (expected,) = struct.unpack(">I", s[-4:])
+    # print "actual =", hex(actual), "expected =", hex(expected)
+    return (actual == expected, msg)