class AwlStructInstance(object):
"Data structure instance"
def __init__(self, struct):
# Store a reference to the data structure
self.struct = struct
# Allocate self.dataBytes
from awlsim.core.datatypes import ByteArray
self.dataBytes = ByteArray(self.struct.getSize())
# Initialize the data structure
for field in self.struct.fields:
if not field.initBytes:
continue
try:
self.dataBytes.store(field.offset, field.bitSize,
field.initBytes)
except AwlSimError as e:
raise AwlSimError("Data structure field '%s' "
"initialization is out of range." %\
str(field))
def getFieldData(self, field, baseOffset=None):
if baseOffset is None:
return self.dataBytes.fetch(field.offset, field.bitSize)
return self.dataBytes.fetch(baseOffset + field.offset, field.bitSize)
def setFieldData(self, field, value, baseOffset=None):
if baseOffset is None:
self.dataBytes.store(field.offset,
field.bitSize, value)
else:
self.dataBytes.store(baseOffset + field.offset,
field.bitSize, value)
def getFieldDataByName(self, name):
return self.getFieldData(self.struct.getField(name))
def setFieldDataByName(self, name, value):
self.setFieldData(self.struct.getField(name), value)
def __init__(self, struct):
# Store a reference to the data structure
self.struct = struct
# Allocate self.dataBytes
from awlsim.core.datatypes import ByteArray
self.dataBytes = ByteArray(self.struct.getSize())
# Initialize the data structure
for field in self.struct.fields:
if not field.initBytes:
continue
try:
self.dataBytes.store(field.offset, field.bitSize,
field.initBytes)
except AwlSimError as e:
raise AwlSimError("Data structure field '%s' "
"initialization is out of range." %\
str(field))
def addField(self, cpu, name, dataType, initBytes=None):
if dataType.type == dataType.TYPE_UDT_X:
# Add an UDT.
try:
udt = cpu.udts[dataType.index]
except KeyError:
assert(0) # Should never happen
assert(not initBytes)
# Assign the struct to the UDT data type, if
# not already done so.
assert(dataType.struct is None or
dataType.struct is udt.struct)
dataType.setStruct(udt.struct)
# Merge the UDT struct with this struct.
return self.merge(udt.struct, name, dataType)
if dataType.width < 0:
raise AwlSimError("Width of data structure field '%s : %s' "
"is undefined. This probably means that its data "
"type is unsupported." %\
(name, str(dataType)))
if dataType.type == dataType.TYPE_STRUCT or\
dataType.type == dataType.TYPE_STRING:
# Add a STRUCT (or STRING, which is represented as struct).
# The struct is represented by the data types struct.
# Merge the data type struct into this struct.
assert(dataType.struct)
baseField = self.merge(dataType.struct, name, dataType)
baseField.override = AwlStructField(baseField.name,
baseField.offset,
"VOID")
baseField.initBytes = initBytes
if dataType.type == dataType.TYPE_ARRAY:
# Add an ARRAY.
# First add a field with the array's name.
# It has the data type 'ARRAY' and is informational only.
offset = AwlOffset(self.getUnalignedSize())
baseField = AwlStructField(name, offset, dataType,
override = AwlStructField(name, offset,
"VOID"))
self.__registerField(baseField)
# Add fields for each ARRAY entry.
initOffset = AwlOffset()
childIdent = AwlDataIdent(name,
[ d[0] for d in dataType.arrayDimensions ],
doValidateName = False)
childType = dataType.arrayElementType
if not childType.allowedInArray:
raise AwlSimError("Data type '%s' not allowed in ARRAY" %\
str(childType))
for i in range(dataType.arrayGetNrElements()):
try:
if not initBytes:
raise ValueError
fieldInitData = ByteArray(intDivRoundUp(childType.width, 8))
fieldInitData.store(AwlOffset(), childType.width,
initBytes.fetch(initOffset,
childType.width))
except (AwlSimError, ValueError) as e:
fieldInitData = None
self.addField(cpu, str(childIdent), childType,
fieldInitData)
initOffset += AwlOffset.fromBitOffset(childType.width)
childIdent.advanceToNextArrayElement(dataType.arrayDimensions)
if childType.width > 8 and\
intDivRoundUp(childType.width, 8) % 2 != 0:
# Align each element to 2-byte-boundary, if word or bigger.
self.addField(cpu, None, AwlDataType.makeByName("BYTE"))
# Add a zero-length array-end guard field,
# to enforce alignment of following fields.
self.addDummyField()
if dataType.type not in {dataType.TYPE_ARRAY,
dataType.TYPE_STRUCT,
dataType.TYPE_STRING}:
# Add a single data type.
if dataType.width == 1 and self.fields and\
self.fields[-1].bitSize == 1 and\
self.fields[-1].offset.bitOffset < 7:
# Consecutive bitfields are merged into one byte
offset = AwlOffset(self.fields[-1].offset.byteOffset,
self.fields[-1].offset.bitOffset + 1)
else:
offset = AwlOffset(self.getUnalignedSize())
baseField = AwlStructField(name, offset, dataType, initBytes)
self.__registerField(baseField)
return baseField
