1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
# -*- coding: utf-8 -*-
#
# AWL simulator - data structs
# Copyright 2013 Michael Buesch <m@bues.ch>
#
# Licensed under the terms of the GNU General Public License version 2.
#
from util import *
from awldatatypes import *
class AwlStructField(object):
"Data structure field"
def __init__(self, name, offset, bitSize, initialValue=0):
self.name = name
self.offset = offset
self.__bitSize = bitSize # Size, in bits
assert(self.__bitSize in (1, 8, 16, 32))
self.initialValue = initialValue
# Return size, in bits.
@property
def bitSize(self):
return self.__bitSize
# Return size, in bytes.
@property
def byteSize(self):
return intDivRoundUp(self.bitSize, 8)
class AwlStruct(object):
"Data structure"
def __init__(self):
self.fields = []
self.name2field = {}
# Return size, in bytes.
def getSize(self):
if not self.fields:
return 0
lastField = self.fields[-1]
return lastField.offset.byteOffset + lastField.byteSize
def addField(self, name, bitSize):
if not bitSize:
return
if bitSize == 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.getSize())
field = AwlStructField(name, offset, bitSize)
self.fields.append(field)
if name:
self.name2field[name] = field
def addFieldAligned(self, name, bitSize, byteAlignment):
padding = byteAlignment - self.getSize() % byteAlignment
if padding == byteAlignment:
padding = 0
self.addField(None, padding * 8)
self.addField(name, bitSize)
def addFieldNaturallyAligned(self, name, bitSize):
alignment = 1
if bitSize > 8:
alignment = 2
self.addFieldAligned(name, bitSize, alignment)
def getField(self, name):
try:
return self.name2field[name]
except KeyError:
raise AwlSimError("Data structure field '%s' not found" % name)
class AwlStructInstanceByte(GenericByte):
"Data structure byte"
def __init__(self, value=0):
GenericByte.__init__(self, value)
class AwlStructInstance(object):
"Data structure instance"
def __init__(self, struct):
self.struct = struct
self.__allocate()
def __allocate(self):
self.dataBytes = []
for field in self.struct.fields:
bsize = field.byteSize
value = field.initialValue
for i in range(field.byteSize):
b = (value >> ((bsize - i - 1) * 8)) & 0xFF
self.dataBytes.append(AwlStructInstanceByte(b))
def getData(self, offset, bitSize):
if bitSize % 8 == 0:
nrBytes, value = bitSize // 8, 0
off = offset.byteOffset
assert(offset.bitOffset == 0)
while nrBytes:
value = (value << 8) | self.dataBytes[off].get()
nrBytes -= 1
off += 1
return value
if bitSize == 1:
return self.dataBytes[offset.byteOffset].getBit(offset.bitOffset)
raise AwlSimError("Invalid struct fetch of %d bits" % bitSize)
def setData(self, offset, bitSize, value):
if bitSize % 8 == 0:
nrBytes = bitSize // 8
off = offset.byteOffset + nrBytes - 1
assert(offset.bitOffset == 0)
while nrBytes:
self.dataBytes[off].set(value)
value >>= 8
nrBytes -= 1
off -= 1
return
if bitSize == 1:
self.dataBytes[offset.byteOffset].setBitValue(
offset.bitOffset, value)
return
raise AwlSimError("Invalid struct write of %d bits" % bitSize)
def getFieldData(self, name):
field = self.struct.getField(name)
return self.getData(field.offset, field.bitSize)
def setFieldData(self, name, value):
field = self.struct.getField(name)
self.setData(field.offset, field.bitSize, value)
|
