From 986a3cbe366720970d31f8f9ca79dea29227890f Mon Sep 17 00:00:00 2001
From: Sven Robertz <sven@cs.lth.se>
Date: Thu, 21 Feb 2013 15:45:28 +0100
Subject: [PATCH] probably implemented packed32 in python
---
lib/python/labcomm/LabComm.py | 48 ++++++++++++++++++++++++++---------
1 file changed, 36 insertions(+), 12 deletions(-)
diff --git a/lib/python/labcomm/LabComm.py b/lib/python/labcomm/LabComm.py
index e0a6808..e13f289 100644
--- a/lib/python/labcomm/LabComm.py
+++ b/lib/python/labcomm/LabComm.py
@@ -89,6 +89,12 @@
#?? +----+----+----+----+
#
#
+# type numbers and lengths do not have a fixed lenght, but are packed into sequences
+# of 7 bit chunks, represented in bytes with the high bit meaning that more data
+# is to come.
+#
+# The chunks are sent "little endian": each 7 bit chunk is more significant than
+# the previous. See encode_packed32 and decode_packed32 in in Codec classes below.
import struct as packer
@@ -306,9 +312,9 @@ class array(object):
def encode_decl(self, encoder):
encoder.encode_type(i_ARRAY)
- encoder.encode_int(len(self.indices))
+ encoder.encode_packed32(len(self.indices))
for i in self.indices:
- encoder.encode_int(i)
+ encoder.encode_packed32(i)
encoder.encode_type_number(self.decl)
def min_max_shape(self, l, depth=0, shape=[]):
@@ -344,7 +350,7 @@ class array(object):
(shape, self.indices))
for i in range(len(self.indices)):
if self.indices[i] == 0:
- encoder.encode_int(shape[i])
+ encoder.encode_packed32(shape[i])
elif self.indices[i] != shape[i]:
raise Exception("Actual dimension %d in %s differs from %s" %
(i, shape, self.indices))
@@ -362,10 +368,10 @@ class array(object):
self.encode_value(encoder, value, depth)
def decode_decl(self, decoder):
- n_indices = decoder.decode_int()
+ n_indices = decoder.decode_packed32()
indices = []
for i in range(n_indices):
- index = decoder.decode_int()
+ index = decoder.decode_packed32()
indices.append(index)
elem_decl = decoder.decode_decl()
return array(indices, elem_decl)
@@ -383,7 +389,7 @@ class array(object):
indices = []
for i in self.indices:
if i == 0:
- i = decoder.decode_int()
+ i = decoder.decode_packed32()
indices.append(i)
return self.decode_value(decoder, indices)
@@ -400,7 +406,7 @@ class array(object):
indices = []
for i in self.indices:
if i == 0:
- i = decoder.decode_int()
+ i = decoder.decode_packed32()
indices.append(i)
return self.new_instance_value(indices)
@@ -414,7 +420,7 @@ class struct:
def encode_decl(self, encoder):
encoder.encode_type(i_STRUCT)
- encoder.encode_int(len(self.field))
+ encoder.encode_packed32(len(self.field))
for (name, decl) in self.field:
encoder.encode_string(name)
encoder.encode_type_number(decl)
@@ -429,7 +435,7 @@ class struct:
decl.encode(encoder, obj.__getattribute__(name))
def decode_decl(self, decoder):
- n_field = decoder.decode_int()
+ n_field = decoder.decode_packed32()
field = []
for i in range(n_field):
name = decoder.decode_string()
@@ -540,7 +546,7 @@ class Codec(object):
index.sort()
for i in index:
e = self.index_to_decl[i]
- if i >= 0x80 and isinstance(e, sample):
+ if i >= i_USER and isinstance(e, sample):
result.append(e)
return result
@@ -573,6 +579,14 @@ class Encoder(Codec):
except KeyError:
decl.encode_decl(self)
+ def encode_packed32(self, v):
+ tmp = v & 0xffffffff;
+
+ while(tmp >= 0x80 ):
+ self.encode_byte( (tmp & 0x7f) | 0x80 )
+ tmp >>= 7
+ self.encode_byte(tmp & 0x7f)
+
def encode_type(self, index):
self.pack("!i", index)
@@ -648,8 +662,18 @@ class Decoder(Codec):
return result
+ def decode_packed32(self):
+ res = 0
+ i = 0
+ cont = True
+ while (cont):
+ c = self.decode_byte()
+ res |= (c & 0x7f) << 7*i
+ cont = (c & 0x80) != 0;
+ return res
+
def decode_type_number(self):
- return self.unpack("!i")
+ return self.decode_packed32()
def decode_boolean(self):
return self.unpack("!b") != 0
@@ -673,7 +697,7 @@ class Decoder(Codec):
return self.unpack("!d")
def decode_string(self):
- length = self.unpack("!i")
+ length = self.decode_packed32()
return self.unpack("!%ds" % length).decode("utf8")
--
GitLab