[svn r57756] * create new contrib directory

* move py/green to contrib/pygreen,
  fix tests and code to pass

--HG--
branch : trunk

contrib/pygreen/msgstruct.py

@@ -0,0 +1,29 @@
+from struct import pack, unpack, calcsize
+
+
+def message(tp, *values):
+    strtype = type('')
+    typecodes = ['']
+    for v in values:
+        if type(v) is strtype:
+            typecodes.append('%ds' % len(v))
+        elif 0 <= v < 256:
+            typecodes.append('B')
+        else:
+            typecodes.append('l')
+    typecodes = ''.join(typecodes)
+    assert len(typecodes) < 256
+    return pack(("!B%dsc" % len(typecodes)) + typecodes,
+                len(typecodes), typecodes, tp, *values)
+
+def decodemessage(data):
+    if data:
+        limit = ord(data[0]) + 1
+        if len(data) >= limit:
+            typecodes = "!c" + data[1:limit]
+            end = limit + calcsize(typecodes)
+            if len(data) >= end:
+                return unpack(typecodes, data[limit:end]), data[end:]
+            #elif end > 1000000:
+            #    raise OverflowError
+    return None, data