(root)/
Python-3.12.0/
Lib/
test/
test_fcntl.py
       1  """Test program for the fcntl C module.
       2  """
       3  import multiprocessing
       4  import platform
       5  import os
       6  import struct
       7  import sys
       8  import unittest
       9  from test.support import verbose, cpython_only, get_pagesize
      10  from test.support.import_helper import import_module
      11  from test.support.os_helper import TESTFN, unlink
      12  
      13  
      14  # Skip test if no fcntl module.
      15  fcntl = import_module('fcntl')
      16  
      17  
      18  
      19  class ESC[4;38;5;81mBadFile:
      20      def __init__(self, fn):
      21          self.fn = fn
      22      def fileno(self):
      23          return self.fn
      24  
      25  def try_lockf_on_other_process_fail(fname, cmd):
      26      f = open(fname, 'wb+')
      27      try:
      28          fcntl.lockf(f, cmd)
      29      except BlockingIOError:
      30          pass
      31      finally:
      32          f.close()
      33  
      34  def try_lockf_on_other_process(fname, cmd):
      35      f = open(fname, 'wb+')
      36      fcntl.lockf(f, cmd)
      37      fcntl.lockf(f, fcntl.LOCK_UN)
      38      f.close()
      39  
      40  class ESC[4;38;5;81mTestFcntl(ESC[4;38;5;149munittestESC[4;38;5;149m.ESC[4;38;5;149mTestCase):
      41  
      42      def setUp(self):
      43          self.f = None
      44  
      45      def tearDown(self):
      46          if self.f and not self.f.closed:
      47              self.f.close()
      48          unlink(TESTFN)
      49  
      50      @staticmethod
      51      def get_lockdata():
      52          try:
      53              os.O_LARGEFILE
      54          except AttributeError:
      55              start_len = "ll"
      56          else:
      57              start_len = "qq"
      58  
      59          if (sys.platform.startswith(('netbsd', 'freebsd', 'openbsd'))
      60              or sys.platform == 'darwin'):
      61              if struct.calcsize('l') == 8:
      62                  off_t = 'l'
      63                  pid_t = 'i'
      64              else:
      65                  off_t = 'lxxxx'
      66                  pid_t = 'l'
      67              lockdata = struct.pack(off_t + off_t + pid_t + 'hh', 0, 0, 0,
      68                                     fcntl.F_WRLCK, 0)
      69          elif sys.platform.startswith('gnukfreebsd'):
      70              lockdata = struct.pack('qqihhi', 0, 0, 0, fcntl.F_WRLCK, 0, 0)
      71          elif sys.platform in ['hp-uxB', 'unixware7']:
      72              lockdata = struct.pack('hhlllii', fcntl.F_WRLCK, 0, 0, 0, 0, 0, 0)
      73          else:
      74              lockdata = struct.pack('hh'+start_len+'hh', fcntl.F_WRLCK, 0, 0, 0, 0, 0)
      75          if lockdata:
      76              if verbose:
      77                  print('struct.pack: ', repr(lockdata))
      78          return lockdata
      79  
      80      def test_fcntl_fileno(self):
      81          # the example from the library docs
      82          self.f = open(TESTFN, 'wb')
      83          rv = fcntl.fcntl(self.f.fileno(), fcntl.F_SETFL, os.O_NONBLOCK)
      84          if verbose:
      85              print('Status from fcntl with O_NONBLOCK: ', rv)
      86          lockdata = self.get_lockdata()
      87          rv = fcntl.fcntl(self.f.fileno(), fcntl.F_SETLKW, lockdata)
      88          if verbose:
      89              print('String from fcntl with F_SETLKW: ', repr(rv))
      90          self.f.close()
      91  
      92      def test_fcntl_file_descriptor(self):
      93          # again, but pass the file rather than numeric descriptor
      94          self.f = open(TESTFN, 'wb')
      95          rv = fcntl.fcntl(self.f, fcntl.F_SETFL, os.O_NONBLOCK)
      96          if verbose:
      97              print('Status from fcntl with O_NONBLOCK: ', rv)
      98          lockdata = self.get_lockdata()
      99          rv = fcntl.fcntl(self.f, fcntl.F_SETLKW, lockdata)
     100          if verbose:
     101              print('String from fcntl with F_SETLKW: ', repr(rv))
     102          self.f.close()
     103  
     104      def test_fcntl_bad_file(self):
     105          with self.assertRaises(ValueError):
     106              fcntl.fcntl(-1, fcntl.F_SETFL, os.O_NONBLOCK)
     107          with self.assertRaises(ValueError):
     108              fcntl.fcntl(BadFile(-1), fcntl.F_SETFL, os.O_NONBLOCK)
     109          with self.assertRaises(TypeError):
     110              fcntl.fcntl('spam', fcntl.F_SETFL, os.O_NONBLOCK)
     111          with self.assertRaises(TypeError):
     112              fcntl.fcntl(BadFile('spam'), fcntl.F_SETFL, os.O_NONBLOCK)
     113  
     114      @cpython_only
     115      def test_fcntl_bad_file_overflow(self):
     116          from _testcapi import INT_MAX, INT_MIN
     117          # Issue 15989
     118          with self.assertRaises(OverflowError):
     119              fcntl.fcntl(INT_MAX + 1, fcntl.F_SETFL, os.O_NONBLOCK)
     120          with self.assertRaises(OverflowError):
     121              fcntl.fcntl(BadFile(INT_MAX + 1), fcntl.F_SETFL, os.O_NONBLOCK)
     122          with self.assertRaises(OverflowError):
     123              fcntl.fcntl(INT_MIN - 1, fcntl.F_SETFL, os.O_NONBLOCK)
     124          with self.assertRaises(OverflowError):
     125              fcntl.fcntl(BadFile(INT_MIN - 1), fcntl.F_SETFL, os.O_NONBLOCK)
     126  
     127      @unittest.skipIf(
     128          platform.machine().startswith('arm') and platform.system() == 'Linux',
     129          "ARM Linux returns EINVAL for F_NOTIFY DN_MULTISHOT")
     130      def test_fcntl_64_bit(self):
     131          # Issue #1309352: fcntl shouldn't fail when the third arg fits in a
     132          # C 'long' but not in a C 'int'.
     133          try:
     134              cmd = fcntl.F_NOTIFY
     135              # This flag is larger than 2**31 in 64-bit builds
     136              flags = fcntl.DN_MULTISHOT
     137          except AttributeError:
     138              self.skipTest("F_NOTIFY or DN_MULTISHOT unavailable")
     139          fd = os.open(os.path.dirname(os.path.abspath(TESTFN)), os.O_RDONLY)
     140          try:
     141              fcntl.fcntl(fd, cmd, flags)
     142          finally:
     143              os.close(fd)
     144  
     145      def test_flock(self):
     146          # Solaris needs readable file for shared lock
     147          self.f = open(TESTFN, 'wb+')
     148          fileno = self.f.fileno()
     149          fcntl.flock(fileno, fcntl.LOCK_SH)
     150          fcntl.flock(fileno, fcntl.LOCK_UN)
     151          fcntl.flock(self.f, fcntl.LOCK_SH | fcntl.LOCK_NB)
     152          fcntl.flock(self.f, fcntl.LOCK_UN)
     153          fcntl.flock(fileno, fcntl.LOCK_EX)
     154          fcntl.flock(fileno, fcntl.LOCK_UN)
     155  
     156          self.assertRaises(ValueError, fcntl.flock, -1, fcntl.LOCK_SH)
     157          self.assertRaises(TypeError, fcntl.flock, 'spam', fcntl.LOCK_SH)
     158  
     159      @unittest.skipIf(platform.system() == "AIX", "AIX returns PermissionError")
     160      def test_lockf_exclusive(self):
     161          self.f = open(TESTFN, 'wb+')
     162          cmd = fcntl.LOCK_EX | fcntl.LOCK_NB
     163          fcntl.lockf(self.f, cmd)
     164          mp = multiprocessing.get_context('spawn')
     165          p = mp.Process(target=try_lockf_on_other_process_fail, args=(TESTFN, cmd))
     166          p.start()
     167          p.join()
     168          fcntl.lockf(self.f, fcntl.LOCK_UN)
     169          self.assertEqual(p.exitcode, 0)
     170  
     171      @unittest.skipIf(platform.system() == "AIX", "AIX returns PermissionError")
     172      def test_lockf_share(self):
     173          self.f = open(TESTFN, 'wb+')
     174          cmd = fcntl.LOCK_SH | fcntl.LOCK_NB
     175          fcntl.lockf(self.f, cmd)
     176          mp = multiprocessing.get_context('spawn')
     177          p = mp.Process(target=try_lockf_on_other_process, args=(TESTFN, cmd))
     178          p.start()
     179          p.join()
     180          fcntl.lockf(self.f, fcntl.LOCK_UN)
     181          self.assertEqual(p.exitcode, 0)
     182  
     183      @cpython_only
     184      def test_flock_overflow(self):
     185          import _testcapi
     186          self.assertRaises(OverflowError, fcntl.flock, _testcapi.INT_MAX+1,
     187                            fcntl.LOCK_SH)
     188  
     189      @unittest.skipIf(sys.platform != 'darwin', "F_GETPATH is only available on macos")
     190      def test_fcntl_f_getpath(self):
     191          self.f = open(TESTFN, 'wb')
     192          expected = os.path.abspath(TESTFN).encode('utf-8')
     193          res = fcntl.fcntl(self.f.fileno(), fcntl.F_GETPATH, bytes(len(expected)))
     194          self.assertEqual(expected, res)
     195  
     196      @unittest.skipUnless(
     197          hasattr(fcntl, "F_SETPIPE_SZ") and hasattr(fcntl, "F_GETPIPE_SZ"),
     198          "F_SETPIPE_SZ and F_GETPIPE_SZ are not available on all platforms.")
     199      def test_fcntl_f_pipesize(self):
     200          test_pipe_r, test_pipe_w = os.pipe()
     201          try:
     202              # Get the default pipesize with F_GETPIPE_SZ
     203              pipesize_default = fcntl.fcntl(test_pipe_w, fcntl.F_GETPIPE_SZ)
     204              pipesize = pipesize_default // 2  # A new value to detect change.
     205              pagesize_default = get_pagesize()
     206              if pipesize < pagesize_default:  # the POSIX minimum
     207                  raise unittest.SkipTest(
     208                      'default pipesize too small to perform test.')
     209              fcntl.fcntl(test_pipe_w, fcntl.F_SETPIPE_SZ, pipesize)
     210              self.assertEqual(fcntl.fcntl(test_pipe_w, fcntl.F_GETPIPE_SZ),
     211                               pipesize)
     212          finally:
     213              os.close(test_pipe_r)
     214              os.close(test_pipe_w)
     215  
     216  
     217  if __name__ == '__main__':
     218      unittest.main()