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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
|
from test_support import verify, vereq, TESTFN
import mmap
import os, re
PAGESIZE = mmap.PAGESIZE
def test_both():
"Test mmap module on Unix systems and Windows"
# Create a file to be mmap'ed.
if os.path.exists(TESTFN):
os.unlink(TESTFN)
f = open(TESTFN, 'w+')
try: # unlink TESTFN no matter what
# Write 2 pages worth of data to the file
f.write('\0'* PAGESIZE)
f.write('foo')
f.write('\0'* (PAGESIZE-3) )
m = mmap.mmap(f.fileno(), 2 * PAGESIZE)
f.close()
# Simple sanity checks
print type(m) # SF bug 128713: segfaulted on Linux
print ' Position of foo:', m.find('foo') / float(PAGESIZE), 'pages'
vereq(m.find('foo'), PAGESIZE)
print ' Length of file:', len(m) / float(PAGESIZE), 'pages'
vereq(len(m), 2*PAGESIZE)
print ' Contents of byte 0:', repr(m[0])
vereq(m[0], '\0')
print ' Contents of first 3 bytes:', repr(m[0:3])
vereq(m[0:3], '\0\0\0')
# Modify the file's content
print "\n Modifying file's content..."
m[0] = '3'
m[PAGESIZE +3: PAGESIZE +3+3] = 'bar'
# Check that the modification worked
print ' Contents of byte 0:', repr(m[0])
vereq(m[0], '3')
print ' Contents of first 3 bytes:', repr(m[0:3])
vereq(m[0:3], '3\0\0')
print ' Contents of second page:', repr(m[PAGESIZE-1 : PAGESIZE + 7])
vereq(m[PAGESIZE-1 : PAGESIZE + 7], '\0foobar\0')
m.flush()
# Test doing a regular expression match in an mmap'ed file
match = re.search('[A-Za-z]+', m)
if match is None:
print ' ERROR: regex match on mmap failed!'
else:
start, end = match.span(0)
length = end - start
print ' Regex match on mmap (page start, length of match):',
print start / float(PAGESIZE), length
vereq(start, PAGESIZE)
vereq(end, PAGESIZE + 6)
# test seeking around (try to overflow the seek implementation)
m.seek(0,0)
print ' Seek to zeroth byte'
vereq(m.tell(), 0)
m.seek(42,1)
print ' Seek to 42nd byte'
vereq(m.tell(), 42)
m.seek(0,2)
print ' Seek to last byte'
vereq(m.tell(), len(m))
print ' Try to seek to negative position...'
try:
m.seek(-1)
except ValueError:
pass
else:
verify(0, 'expected a ValueError but did not get it')
print ' Try to seek beyond end of mmap...'
try:
m.seek(1,2)
except ValueError:
pass
else:
verify(0, 'expected a ValueError but did not get it')
print ' Try to seek to negative position...'
try:
m.seek(-len(m)-1,2)
except ValueError:
pass
else:
verify(0, 'expected a ValueError but did not get it')
# Try resizing map
print ' Attempting resize()'
try:
m.resize( 512 )
except SystemError:
# resize() not supported
# No messages are printed, since the output of this test suite
# would then be different across platforms.
pass
else:
# resize() is supported
verify(len(m) == 512,
"len(m) is %d, but expecting 512" % (len(m),) )
# Check that we can no longer seek beyond the new size.
try:
m.seek(513,0)
except ValueError:
pass
else:
verify(0, 'Could seek beyond the new size')
m.close()
finally:
try:
f.close()
except OSError:
pass
try:
os.unlink(TESTFN)
except OSError:
pass
# Test for "access" keyword parameter
try:
mapsize = 10
print " Creating", mapsize, "byte test data file."
open(TESTFN, "wb").write("a"*mapsize)
print " Opening mmap with access=ACCESS_READ"
f = open(TESTFN, "rb")
m = mmap.mmap(f.fileno(), mapsize, access=mmap.ACCESS_READ)
verify(m[:] == 'a'*mapsize, "Readonly memory map data incorrect.")
print " Ensuring that readonly mmap can't be slice assigned."
try:
m[:] = 'b'*mapsize
except TypeError:
pass
else:
verify(0, "Able to write to readonly memory map")
print " Ensuring that readonly mmap can't be item assigned."
try:
m[0] = 'b'
except TypeError:
pass
else:
verify(0, "Able to write to readonly memory map")
print " Ensuring that readonly mmap can't be write() to."
try:
m.seek(0,0)
m.write('abc')
except TypeError:
pass
else:
verify(0, "Able to write to readonly memory map")
print " Ensuring that readonly mmap can't be write_byte() to."
try:
m.seek(0,0)
m.write_byte('d')
except TypeError:
pass
else:
verify(0, "Able to write to readonly memory map")
print " Ensuring that readonly mmap can't be resized."
try:
m.resize(2*mapsize)
except SystemError: # resize is not universally supported
pass
except TypeError:
pass
else:
verify(0, "Able to resize readonly memory map")
del m, f
verify(open(TESTFN, "rb").read() == 'a'*mapsize,
"Readonly memory map data file was modified")
print " Opening mmap with access=ACCESS_WRITE"
f = open(TESTFN, "r+b")
m = mmap.mmap(f.fileno(), mapsize, access=mmap.ACCESS_WRITE)
print " Modifying write-through memory map."
m[:] = 'c'*mapsize
verify(m[:] == 'c'*mapsize,
"Write-through memory map memory not updated properly.")
m.flush()
del m, f
verify(open(TESTFN).read() == 'c'*mapsize,
"Write-through memory map data file not updated properly.")
print " Opening mmap with access=ACCESS_COPY"
f = open(TESTFN, "r+b")
m = mmap.mmap(f.fileno(), mapsize, access=mmap.ACCESS_COPY)
print " Modifying copy-on-write memory map."
m[:] = 'd'*mapsize
verify(m[:] == 'd' * mapsize,
"Copy-on-write memory map data not written correctly.")
m.flush()
verify(open(TESTFN, "rb").read() == 'c'*mapsize,
"Copy-on-write test data file should not be modified.")
try:
print " Ensuring copy-on-write maps cannot be resized."
m.resize(2*mapsize)
except TypeError:
pass
else:
verify(0, "Copy-on-write mmap resize did not raise exception.")
del m, f
try:
print " Ensuring invalid access parameter raises exception."
f = open(TESTFN, "r+b")
m = mmap.mmap(f.fileno(), mapsize, access=4)
except ValueError:
pass
else:
verify(0, "Invalid access code should have raised exception.")
if os.name == "posix":
# Try incompatible flags, prot and access parameters.
f = open(TESTFN, "r+b")
try:
m = mmap.mmap(f.fileno(), mapsize, flags=mmap.MAP_PRIVATE,
prot=mmap.PROT_READ, access=mmap.ACCESS_WRITE)
except ValueError:
pass
else:
verify(0, "Incompatible parameters should raise ValueError.")
finally:
try:
os.unlink(TESTFN)
except OSError:
pass
print ' Test passed'
test_both()
|
