def encode_value_length(value_length, writer):
"""Enocde the length of a value as a
var_width length. This will be the smallest of
a byte, short or int which can hold the length.
Arguments:
value_length: the length in buytes of the value object
writer: the writer object to write the length to
"""
assert value_length >= 0 and value_length <= utils.MAX_INT
if value_length <= utils.MAX_BYTE:
writer.write(codecs.enc_byte(value_length))
elif value_length <= utils.MAX_SHORT:
writer.write(codecs.enc_short(value_length))
else:
writer.write(codecs.enc_int(value_length))
def encode_value_length(value_length, writer):
"""Enocde the length of a value as a
var_width length. This will be the smallest of
a byte, short or int which can hold the length.
Arguments:
value_length: the length in buytes of the value object
writer: the writer object to write the length to
"""
assert value_length >= 0 and value_length <= utils.MAX_INT
if value_length <= utils.MAX_BYTE:
writer.write(codecs.enc_byte(value_length))
elif value_length <= utils.MAX_SHORT:
writer.write(codecs.enc_short(value_length))
else:
writer.write(codecs.enc_int(value_length))
def encode(self, writer, taxonomy=None):
"""Encode a Field.
This encodes Field Prefix, Type, Ordinal, Name, Data
"""
variable_width = 0
if self.type_.is_variable_sized:
if self.is_type(types.FUDGEMSG_TYPE_ID):
# sub-message, need to be taxonomy aware
value_length = self.type_.calc_size(self.value, taxonomy)
else:
value_length = self.type_.calc_size(self.value)
variable_width = bytes_for_value_length(value_length)
ordinal = self.ordinal
name = self.name
if taxonomy and self.name:
tax_ord = taxonomy.get_ordinal(self.name)
if tax_ord:
ordinal = tax_ord
name = None
prefix_byte = prefix.encode_prefix(not self.type_.is_variable_sized, \
variable_width, ordinal is not None, name is not None)
# And write it out
writer.write(chr(prefix_byte))
writer.write(codecs.enc_byte(self.type_.type_id))
if ordinal is not None:
writer.write(codecs.enc_short(ordinal))
if name:
assert len(name) <= utils.MAX_BYTE
writer.write(codecs.enc_name(name))
if self.type_.is_variable_sized:
encode_value_length(value_length, writer)
if self.is_type(types.FUDGEMSG_TYPE_ID):
self.value.encode(writer, taxonomy)
else:
writer.write(self.type_.encoder(self.value))
def encode(self, writer, taxonomy=None):
"""Encode a Field.
This encodes Field Prefix, Type, Ordinal, Name, Data
"""
variable_width = 0
if self.type_.is_variable_sized:
if self.is_type(types.FUDGEMSG_TYPE_ID):
# sub-message, need to be taxonomy aware
value_length = self.type_.calc_size(self.value, taxonomy)
else:
value_length = self.type_.calc_size(self.value)
variable_width = bytes_for_value_length(value_length)
ordinal = self.ordinal
name = self.name
if taxonomy and self.name:
tax_ord = taxonomy.get_ordinal(self.name)
if tax_ord:
ordinal = tax_ord
name = None
prefix_byte = prefix.encode_prefix(not self.type_.is_variable_sized, \
variable_width, ordinal is not None, name is not None)
# And write it out
writer.write(chr(prefix_byte))
writer.write(codecs.enc_byte(self.type_.type_id))
if ordinal is not None:
writer.write(codecs.enc_short(ordinal))
if name:
assert len(name) <= utils.MAX_BYTE
writer.write(codecs.enc_name(name))
if self.type_.is_variable_sized:
encode_value_length(value_length, writer)
if self.is_type(types.FUDGEMSG_TYPE_ID):
self.value.encode(writer, taxonomy)
else:
writer.write(self.type_.encoder(self.value))
