cpython/Lib/test/test_mmap.py
Antoine Pitrou fd036451bf #2834: Change re module semantics, so that str and bytes mixing is forbidden,
and str (unicode) patterns get full unicode matching by default. The re.ASCII
flag is also introduced to ask for ASCII matching instead.
2008-08-19 17:56:33 +00:00

449 lines
14 KiB
Python

from test.support import TESTFN, run_unittest
import mmap
import unittest
import os, re
PAGESIZE = mmap.PAGESIZE
class MmapTests(unittest.TestCase):
def setUp(self):
if os.path.exists(TESTFN):
os.unlink(TESTFN)
def tearDown(self):
try:
os.unlink(TESTFN)
except OSError:
pass
def test_basic(self):
# Test mmap module on Unix systems and Windows
# Create a file to be mmap'ed.
f = open(TESTFN, 'bw+')
try:
# Write 2 pages worth of data to the file
f.write(b'\0'* PAGESIZE)
f.write(b'foo')
f.write(b'\0'* (PAGESIZE-3) )
f.flush()
m = mmap.mmap(f.fileno(), 2 * PAGESIZE)
finally:
f.close()
# Simple sanity checks
tp = str(type(m)) # SF bug 128713: segfaulted on Linux
self.assertEqual(m.find('foo'), PAGESIZE)
self.assertEqual(len(m), 2*PAGESIZE)
self.assertEqual(m[0], 0)
self.assertEqual(m[0:3], b'\0\0\0')
# Modify the file's content
m[0] = b'3'[0]
m[PAGESIZE +3: PAGESIZE +3+3] = b'bar'
# Check that the modification worked
self.assertEqual(m[0], b'3'[0])
self.assertEqual(m[0:3], b'3\0\0')
self.assertEqual(m[PAGESIZE-1 : PAGESIZE + 7], b'\0foobar\0')
m.flush()
# Test doing a regular expression match in an mmap'ed file
match = re.search(b'[A-Za-z]+', m)
if match is None:
self.fail('regex match on mmap failed!')
else:
start, end = match.span(0)
length = end - start
self.assertEqual(start, PAGESIZE)
self.assertEqual(end, PAGESIZE + 6)
# test seeking around (try to overflow the seek implementation)
m.seek(0,0)
self.assertEqual(m.tell(), 0)
m.seek(42,1)
self.assertEqual(m.tell(), 42)
m.seek(0,2)
self.assertEqual(m.tell(), len(m))
# Try to seek to negative position...
self.assertRaises(ValueError, m.seek, -1)
# Try to seek beyond end of mmap...
self.assertRaises(ValueError, m.seek, 1, 2)
# Try to seek to negative position...
self.assertRaises(ValueError, m.seek, -len(m)-1, 2)
# Try resizing map
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
self.assertEqual(len(m), 512)
# Check that we can no longer seek beyond the new size.
self.assertRaises(ValueError, m.seek, 513, 0)
# Check that the underlying file is truncated too
# (bug #728515)
f = open(TESTFN)
try:
f.seek(0, 2)
self.assertEqual(f.tell(), 512)
finally:
f.close()
self.assertEqual(m.size(), 512)
m.close()
def test_access_parameter(self):
# Test for "access" keyword parameter
mapsize = 10
open(TESTFN, "wb").write(b"a"*mapsize)
f = open(TESTFN, "rb")
m = mmap.mmap(f.fileno(), mapsize, access=mmap.ACCESS_READ)
self.assertEqual(m[:], b'a'*mapsize, "Readonly memory map data incorrect.")
# Ensuring that readonly mmap can't be slice assigned
try:
m[:] = b'b'*mapsize
except TypeError:
pass
else:
self.fail("Able to write to readonly memory map")
# Ensuring that readonly mmap can't be item assigned
try:
m[0] = b'b'
except TypeError:
pass
else:
self.fail("Able to write to readonly memory map")
# Ensuring that readonly mmap can't be write() to
try:
m.seek(0,0)
m.write(b'abc')
except TypeError:
pass
else:
self.fail("Able to write to readonly memory map")
# Ensuring that readonly mmap can't be write_byte() to
try:
m.seek(0,0)
m.write_byte(b'd')
except TypeError:
pass
else:
self.fail("Able to write to readonly memory map")
# 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:
self.fail("Able to resize readonly memory map")
f.close()
del m, f
self.assertEqual(open(TESTFN, "rb").read(), b'a'*mapsize,
"Readonly memory map data file was modified")
# Opening mmap with size too big
import sys
f = open(TESTFN, "r+b")
try:
m = mmap.mmap(f.fileno(), mapsize+1)
except ValueError:
# we do not expect a ValueError on Windows
# CAUTION: This also changes the size of the file on disk, and
# later tests assume that the length hasn't changed. We need to
# repair that.
if sys.platform.startswith('win'):
self.fail("Opening mmap with size+1 should work on Windows.")
else:
# we expect a ValueError on Unix, but not on Windows
if not sys.platform.startswith('win'):
self.fail("Opening mmap with size+1 should raise ValueError.")
m.close()
f.close()
if sys.platform.startswith('win'):
# Repair damage from the resizing test.
f = open(TESTFN, 'r+b')
f.truncate(mapsize)
f.close()
# Opening mmap with access=ACCESS_WRITE
f = open(TESTFN, "r+b")
m = mmap.mmap(f.fileno(), mapsize, access=mmap.ACCESS_WRITE)
# Modifying write-through memory map
m[:] = b'c'*mapsize
self.assertEqual(m[:], b'c'*mapsize,
"Write-through memory map memory not updated properly.")
m.flush()
m.close()
f.close()
f = open(TESTFN, 'rb')
stuff = f.read()
f.close()
self.assertEqual(stuff, b'c'*mapsize,
"Write-through memory map data file not updated properly.")
# Opening mmap with access=ACCESS_COPY
f = open(TESTFN, "r+b")
m = mmap.mmap(f.fileno(), mapsize, access=mmap.ACCESS_COPY)
# Modifying copy-on-write memory map
m[:] = b'd'*mapsize
self.assertEqual(m[:], b'd' * mapsize,
"Copy-on-write memory map data not written correctly.")
m.flush()
self.assertEqual(open(TESTFN, "rb").read(), b'c'*mapsize,
"Copy-on-write test data file should not be modified.")
# Ensuring copy-on-write maps cannot be resized
self.assertRaises(TypeError, m.resize, 2*mapsize)
f.close()
del m, f
# Ensuring invalid access parameter raises exception
f = open(TESTFN, "r+b")
self.assertRaises(ValueError, mmap.mmap, f.fileno(), mapsize, access=4)
f.close()
if os.name == "posix":
# Try incompatible flags, prot and access parameters.
f = open(TESTFN, "r+b")
self.assertRaises(ValueError, mmap.mmap, f.fileno(), mapsize,
flags=mmap.MAP_PRIVATE,
prot=mmap.PROT_READ, access=mmap.ACCESS_WRITE)
f.close()
def test_bad_file_desc(self):
# Try opening a bad file descriptor...
self.assertRaises(mmap.error, mmap.mmap, -2, 4096)
def test_tougher_find(self):
# Do a tougher .find() test. SF bug 515943 pointed out that, in 2.2,
# searching for data with embedded \0 bytes didn't work.
f = open(TESTFN, 'wb+')
data = b'aabaac\x00deef\x00\x00aa\x00'
n = len(data)
f.write(data)
f.flush()
m = mmap.mmap(f.fileno(), n)
f.close()
for start in range(n+1):
for finish in range(start, n+1):
slice = data[start : finish]
self.assertEqual(m.find(slice), data.find(slice))
self.assertEqual(m.find(slice + b'x'), -1)
m.close()
def test_find_end(self):
# test the new 'end' parameter works as expected
f = open(TESTFN, 'w+')
data = 'one two ones'
n = len(data)
f.write(data)
f.flush()
m = mmap.mmap(f.fileno(), n)
f.close()
self.assertEqual(m.find('one'), 0)
self.assertEqual(m.find('ones'), 8)
self.assertEqual(m.find('one', 0, -1), 0)
self.assertEqual(m.find('one', 1), 8)
self.assertEqual(m.find('one', 1, -1), 8)
self.assertEqual(m.find('one', 1, -2), -1)
def test_rfind(self):
# test the new 'end' parameter works as expected
f = open(TESTFN, 'w+')
data = 'one two ones'
n = len(data)
f.write(data)
f.flush()
m = mmap.mmap(f.fileno(), n)
f.close()
self.assertEqual(m.rfind('one'), 8)
self.assertEqual(m.rfind('one '), 0)
self.assertEqual(m.rfind('one', 0, -1), 8)
self.assertEqual(m.rfind('one', 0, -2), 0)
self.assertEqual(m.rfind('one', 1, -1), 8)
self.assertEqual(m.rfind('one', 1, -2), -1)
def test_double_close(self):
# make sure a double close doesn't crash on Solaris (Bug# 665913)
f = open(TESTFN, 'wb+')
f.write(2**16 * b'a') # Arbitrary character
f.close()
f = open(TESTFN)
mf = mmap.mmap(f.fileno(), 2**16, access=mmap.ACCESS_READ)
mf.close()
mf.close()
f.close()
def test_entire_file(self):
# test mapping of entire file by passing 0 for map length
if hasattr(os, "stat"):
f = open(TESTFN, "wb+")
f.write(2**16 * b'm') # Arbitrary character
f.close()
f = open(TESTFN, "rb+")
mf = mmap.mmap(f.fileno(), 0)
self.assertEqual(len(mf), 2**16, "Map size should equal file size.")
self.assertEqual(mf.read(2**16), 2**16 * b"m")
mf.close()
f.close()
def test_move(self):
# make move works everywhere (64-bit format problem earlier)
f = open(TESTFN, 'wb+')
f.write(b"ABCDEabcde") # Arbitrary character
f.flush()
mf = mmap.mmap(f.fileno(), 10)
mf.move(5, 0, 5)
self.assertEqual(mf[:], b"ABCDEABCDE", "Map move should have duplicated front 5")
mf.close()
f.close()
def test_anonymous(self):
# anonymous mmap.mmap(-1, PAGE)
m = mmap.mmap(-1, PAGESIZE)
for x in range(PAGESIZE):
self.assertEqual(m[x], 0,
"anonymously mmap'ed contents should be zero")
for x in range(PAGESIZE):
b = x & 0xff
m[x] = b
self.assertEqual(m[x], b)
def test_extended_getslice(self):
# Test extended slicing by comparing with list slicing.
s = bytes(reversed(range(256)))
m = mmap.mmap(-1, len(s))
m[:] = s
self.assertEqual(m[:], s)
indices = (0, None, 1, 3, 19, 300, -1, -2, -31, -300)
for start in indices:
for stop in indices:
# Skip step 0 (invalid)
for step in indices[1:]:
self.assertEqual(m[start:stop:step],
s[start:stop:step])
def test_extended_set_del_slice(self):
# Test extended slicing by comparing with list slicing.
s = bytes(reversed(range(256)))
m = mmap.mmap(-1, len(s))
indices = (0, None, 1, 3, 19, 300, -1, -2, -31, -300)
for start in indices:
for stop in indices:
# Skip invalid step 0
for step in indices[1:]:
m[:] = s
self.assertEqual(m[:], s)
L = list(s)
# Make sure we have a slice of exactly the right length,
# but with different data.
data = L[start:stop:step]
data = bytes(reversed(data))
L[start:stop:step] = data
m[start:stop:step] = data
self.assertEquals(m[:], bytes(L))
def make_mmap_file (self, f, halfsize):
# Write 2 pages worth of data to the file
f.write (b'\0' * halfsize)
f.write (b'foo')
f.write (b'\0' * (halfsize - 3))
f.flush ()
return mmap.mmap (f.fileno(), 0)
def test_offset (self):
f = open (TESTFN, 'w+b')
try: # unlink TESTFN no matter what
halfsize = mmap.ALLOCATIONGRANULARITY
m = self.make_mmap_file (f, halfsize)
m.close ()
f.close ()
mapsize = halfsize * 2
# Try invalid offset
f = open(TESTFN, "r+b")
for offset in [-2, -1, None]:
try:
m = mmap.mmap(f.fileno(), mapsize, offset=offset)
self.assertEqual(0, 1)
except (ValueError, TypeError, OverflowError):
pass
else:
self.assertEqual(0, 0)
f.close()
# Try valid offset, hopefully 8192 works on all OSes
f = open(TESTFN, "r+b")
m = mmap.mmap(f.fileno(), mapsize - halfsize, offset=halfsize)
self.assertEqual(m[0:3], b'foo')
f.close()
m.close()
finally:
f.close()
try:
os.unlink(TESTFN)
except OSError:
pass
def test_subclass(self):
class anon_mmap(mmap.mmap):
def __new__(klass, *args, **kwargs):
return mmap.mmap.__new__(klass, -1, *args, **kwargs)
anon_mmap(PAGESIZE)
def test_prot_readonly(self):
if not hasattr(mmap, 'PROT_READ'):
return
mapsize = 10
open(TESTFN, "wb").write(b"a"*mapsize)
f = open(TESTFN, "rb")
m = mmap.mmap(f.fileno(), mapsize, prot=mmap.PROT_READ)
self.assertRaises(TypeError, m.write, "foo")
f.close()
def test_error(self):
self.assert_(issubclass(mmap.error, EnvironmentError))
self.assert_("mmap.error" in str(mmap.error))
def test_main():
run_unittest(MmapTests)
if __name__ == '__main__':
test_main()