178 lines
6.5 KiB
Python
178 lines
6.5 KiB
Python
"""Test largefile support on system where this makes sense.
|
|
"""
|
|
|
|
import os
|
|
import stat
|
|
import sys
|
|
import unittest
|
|
from test.test_support import run_unittest, TESTFN, verbose, requires, \
|
|
TestSkipped, unlink
|
|
|
|
try:
|
|
import signal
|
|
# The default handler for SIGXFSZ is to abort the process.
|
|
# By ignoring it, system calls exceeding the file size resource
|
|
# limit will raise IOError instead of crashing the interpreter.
|
|
oldhandler = signal.signal(signal.SIGXFSZ, signal.SIG_IGN)
|
|
except (ImportError, AttributeError):
|
|
pass
|
|
|
|
# create >2GB file (2GB = 2147483648 bytes)
|
|
size = 2500000000L
|
|
|
|
|
|
class TestCase(unittest.TestCase):
|
|
"""Test that each file function works as expected for a large
|
|
(i.e. > 2GB, do we have to check > 4GB) files.
|
|
|
|
NOTE: the order of execution of the test methods is important! test_seek
|
|
must run first to create the test file. File cleanup must also be handled
|
|
outside the test instances because of this.
|
|
|
|
"""
|
|
|
|
def test_seek(self):
|
|
if verbose:
|
|
print 'create large file via seek (may be sparse file) ...'
|
|
with open(TESTFN, 'wb') as f:
|
|
f.write('z')
|
|
f.seek(0)
|
|
f.seek(size)
|
|
f.write('a')
|
|
f.flush()
|
|
if verbose:
|
|
print 'check file size with os.fstat'
|
|
self.assertEqual(os.fstat(f.fileno())[stat.ST_SIZE], size+1)
|
|
|
|
def test_osstat(self):
|
|
if verbose:
|
|
print 'check file size with os.stat'
|
|
self.assertEqual(os.stat(TESTFN)[stat.ST_SIZE], size+1)
|
|
|
|
def test_seek_read(self):
|
|
if verbose:
|
|
print 'play around with seek() and read() with the built largefile'
|
|
with open(TESTFN, 'rb') as f:
|
|
self.assertEqual(f.tell(), 0)
|
|
self.assertEqual(f.read(1), 'z')
|
|
self.assertEqual(f.tell(), 1)
|
|
f.seek(0)
|
|
self.assertEqual(f.tell(), 0)
|
|
f.seek(0, 0)
|
|
self.assertEqual(f.tell(), 0)
|
|
f.seek(42)
|
|
self.assertEqual(f.tell(), 42)
|
|
f.seek(42, 0)
|
|
self.assertEqual(f.tell(), 42)
|
|
f.seek(42, 1)
|
|
self.assertEqual(f.tell(), 84)
|
|
f.seek(0, 1)
|
|
self.assertEqual(f.tell(), 84)
|
|
f.seek(0, 2) # seek from the end
|
|
self.assertEqual(f.tell(), size + 1 + 0)
|
|
f.seek(-10, 2)
|
|
self.assertEqual(f.tell(), size + 1 - 10)
|
|
f.seek(-size-1, 2)
|
|
self.assertEqual(f.tell(), 0)
|
|
f.seek(size)
|
|
self.assertEqual(f.tell(), size)
|
|
# the 'a' that was written at the end of file above
|
|
self.assertEqual(f.read(1), 'a')
|
|
f.seek(-size-1, 1)
|
|
self.assertEqual(f.read(1), 'z')
|
|
self.assertEqual(f.tell(), 1)
|
|
|
|
def test_lseek(self):
|
|
if verbose:
|
|
print 'play around with os.lseek() with the built largefile'
|
|
with open(TESTFN, 'rb') as f:
|
|
self.assertEqual(os.lseek(f.fileno(), 0, 0), 0)
|
|
self.assertEqual(os.lseek(f.fileno(), 42, 0), 42)
|
|
self.assertEqual(os.lseek(f.fileno(), 42, 1), 84)
|
|
self.assertEqual(os.lseek(f.fileno(), 0, 1), 84)
|
|
self.assertEqual(os.lseek(f.fileno(), 0, 2), size+1+0)
|
|
self.assertEqual(os.lseek(f.fileno(), -10, 2), size+1-10)
|
|
self.assertEqual(os.lseek(f.fileno(), -size-1, 2), 0)
|
|
self.assertEqual(os.lseek(f.fileno(), size, 0), size)
|
|
# the 'a' that was written at the end of file above
|
|
self.assertEqual(f.read(1), 'a')
|
|
|
|
def test_truncate(self):
|
|
if verbose:
|
|
print 'try truncate'
|
|
with open(TESTFN, 'r+b') as f:
|
|
# this is already decided before start running the test suite
|
|
# but we do it anyway for extra protection
|
|
if not hasattr(f, 'truncate'):
|
|
raise TestSkipped, "open().truncate() not available on this system"
|
|
f.seek(0, 2)
|
|
# else we've lost track of the true size
|
|
self.assertEqual(f.tell(), size+1)
|
|
# Cut it back via seek + truncate with no argument.
|
|
newsize = size - 10
|
|
f.seek(newsize)
|
|
f.truncate()
|
|
self.assertEqual(f.tell(), newsize) # else pointer moved
|
|
f.seek(0, 2)
|
|
self.assertEqual(f.tell(), newsize) # else wasn't truncated
|
|
# Ensure that truncate(smaller than true size) shrinks
|
|
# the file.
|
|
newsize -= 1
|
|
f.seek(42)
|
|
f.truncate(newsize)
|
|
self.assertEqual(f.tell(), 42) # else pointer moved
|
|
f.seek(0, 2)
|
|
self.assertEqual(f.tell(), newsize) # else wasn't truncated
|
|
|
|
# XXX truncate(larger than true size) is ill-defined
|
|
# across platform; cut it waaaaay back
|
|
f.seek(0)
|
|
f.truncate(1)
|
|
self.assertEqual(f.tell(), 0) # else pointer moved
|
|
self.assertEqual(len(f.read()), 1) # else wasn't truncated
|
|
|
|
|
|
def test_main():
|
|
# On Windows and Mac OSX this test comsumes large resources; It
|
|
# takes a long time to build the >2GB file and takes >2GB of disk
|
|
# space therefore the resource must be enabled to run this test.
|
|
# If not, nothing after this line stanza will be executed.
|
|
if sys.platform[:3] == 'win' or sys.platform == 'darwin':
|
|
requires('largefile',
|
|
'test requires %s bytes and a long time to run' % str(size))
|
|
else:
|
|
# Only run if the current filesystem supports large files.
|
|
# (Skip this test on Windows, since we now always support
|
|
# large files.)
|
|
f = open(TESTFN, 'wb')
|
|
try:
|
|
# 2**31 == 2147483648
|
|
f.seek(2147483649L)
|
|
# Seeking is not enough of a test: you must write and
|
|
# flush, too!
|
|
f.write("x")
|
|
f.flush()
|
|
except (IOError, OverflowError):
|
|
f.close()
|
|
unlink(TESTFN)
|
|
raise TestSkipped, "filesystem does not have largefile support"
|
|
else:
|
|
f.close()
|
|
suite = unittest.TestSuite()
|
|
suite.addTest(TestCase('test_seek'))
|
|
suite.addTest(TestCase('test_osstat'))
|
|
suite.addTest(TestCase('test_seek_read'))
|
|
suite.addTest(TestCase('test_lseek'))
|
|
with open(TESTFN, 'w') as f:
|
|
if hasattr(f, 'truncate'):
|
|
suite.addTest(TestCase('test_truncate'))
|
|
unlink(TESTFN)
|
|
try:
|
|
run_unittest(suite)
|
|
finally:
|
|
unlink(TESTFN)
|
|
|
|
|
|
if __name__ == '__main__':
|
|
test_main()
|