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
|
#!/usr/bin/python
#
# Usage: fileDiffer <afile> <bfile> <list of disk changes>
#
# LUKS
# quick regression test suite
# Tests LUKS images for changes at certain disk offsets
#
# Does fast python code has to look ugly or is it just me?
import sys
class changes:
pass
def parseArgs(args):
aFileName = args[1]
bFileName = args[2]
changelist = []
args[0:3] = []
for i in args:
mychanges = changes();
if i.startswith('A'):
mychanges.mode = 'ALLOWED'
if i.startswith('R'):
mychanges.mode = 'REQUIRED'
mychanges.strictness = 'RANDOM'
if i.startswith('S'):
mychanges.mode = 'REQUIRED'
mychanges.strictness = 'SEMANTIC'
dashIndex = i.find('-')
if dashIndex == -1:
mychanges.starts = int(i[1:])
mychanges.ends = mychanges.starts
else:
mychanges.starts = int(i[1:dashIndex])
mychanges.ends = int(i[dashIndex+1:])
mychanges.miss = 0
changelist.append(mychanges)
mychanges = changes();
mychanges.starts = 0
# mychanges.ends will be fixed later
mychanges.mode = 'FORBIDDEN'
changelist.append(mychanges)
return [aFileName, bFileName, changelist]
def mode(i):
for c in changelist:
if i >= c.starts and i<=c.ends:
return c
def cleanchanges(i):
newchangelist=[]
for c in changelist:
if i <= c.starts or i <= c.ends:
newchangelist.append(c)
return newchangelist
[aFileName, bFileName, changelist] = parseArgs(sys.argv)
aFile = open(aFileName,'r')
bFile = open(bFileName,'r')
aString = aFile.read()
bString = bFile.read()
if len(aString) != len(bString):
sys.exit("Mismatch different file sizes")
fileLen = len(aString)
fileLen10th = fileLen/10
# Create a catch all entry
changelist[-1].ends = fileLen
print "Changes list: (FORBIDDEN default)"
print "start\tend\tmode\t\tstrictness"
for i in changelist:
if i.mode == 'REQUIRED':
print "%d\t%d\t%s\t%s" % (i.starts, i.ends, i.mode, i.strictness)
else:
print "%d\t%d\t%s" % (i.starts, i.ends, i.mode)
filepos = 0
fileLen10thC = 0
print "[..........]"
sys.stdout.write("[")
sys.stdout.flush()
modeNotTrivial = 1
while filepos < fileLen:
if modeNotTrivial == 1:
c = mode(filepos)
# print (filepos, c.mode)
if c.mode == 'REQUIRED':
if aString[filepos] == bString[filepos]:
c.miss = c.miss + 1
else:
if aString[filepos] != bString[filepos] and c.mode != 'ALLOWED':
sys.exit("Mismatch at %d: change forbidden" % filepos)
# Do some maintaince, print progress bar, and clean changelist
#
# Maintaining two counters appears to be faster than modulo operation
if fileLen10thC == fileLen10th:
fileLen10thC = 0
sys.stdout.write(".")
sys.stdout.flush()
changelist = cleanchanges(filepos)
if len(changelist) == 1:
modeNotTrivial = 0
filepos = filepos + 1
fileLen10thC = fileLen10thC + 1
for c in changelist:
if c.mode == 'REQUIRED':
if c.strictness == 'SEMANTIC' and c.miss == (c.ends-c.starts+1):
sys.exit("Mismatch: not even a single change in region %d-%d." % (c.starts, c.ends))
# This is not correct. We should do a statistical test
# of the sampled data against the hypothetical distribution
# of collision. Chi-Square Test.
if c.strictness == 'RANDOM' and c.miss == (c.ends-c.starts+1):
sys.exit("Mismatch: not even a single change in region %d-%d." % (c.starts, c.ends))
print ".] - everything ok"
|
