diff options
| -rw-r--r-- | linuxnamespaces/atlocation.py | 17 | ||||
| -rw-r--r-- | tests/test_atlocation.py | 20 |
2 files changed, 36 insertions, 1 deletions
diff --git a/linuxnamespaces/atlocation.py b/linuxnamespaces/atlocation.py index 6aada55..8da5982 100644 --- a/linuxnamespaces/atlocation.py +++ b/linuxnamespaces/atlocation.py @@ -9,6 +9,7 @@ code for doing so. import enum import errno +import fcntl import os import os.path import pathlib @@ -102,6 +103,22 @@ class AtLocation: os.close(self.fd) self.fd = AT_FDCWD + def as_emptypath(self, inheritable: bool = True) -> "AtLocation": + """Return a new AtLocation with flag AT_EMPTY_PATH with a new file + descriptor. If self already is an empty path, its fd is duplicated. In + all cases, the caller is responsible for closing the result object. + """ + if self.flags & AtFlags.AT_EMPTY_PATH: + newfd = fcntl.fcntl( + self.fd, + fcntl.F_DUPFD if inheritable else fcntl.F_DUPFD_CLOEXEC, + 0, + ) + return AtLocation(newfd, flags=self.flags) + return AtLocation( + self.open(flags=os.O_PATH | (0 if inheritable else os.O_CLOEXEC)) + ) + def nosymfollow(self) -> "AtLocation": """Return a copy with the AT_SYMLINK_NOFOLLOW set.""" return AtLocation( diff --git a/tests/test_atlocation.py b/tests/test_atlocation.py index 9836f3b..5d7286a 100644 --- a/tests/test_atlocation.py +++ b/tests/test_atlocation.py @@ -80,7 +80,7 @@ class AtLocationTest(unittest.TestCase): def create_all( self, skip: typing.Container[str] = () ) -> typing.Iterator[tuple[str, typing.ContextManager[AtLocation]]]: - """Create various AtLocation objects referring to fils, directories + """Create various AtLocation objects referring to files, directories and other things in various ways. """ for loctype in ("relative", "absolute", "emptypath", "withfd"): @@ -146,6 +146,24 @@ class AtLocationTest(unittest.TestCase): self.assertEqual(atloc.access(os.R_OK), should_exist) self.assertEqual(atloc.exists(), should_exist) + def test_as_emptypath(self) -> None: + atloc = AtLocation(self.tempdir) + self.assertFalse(atloc.flags & linuxnamespaces.AtFlags.AT_EMPTY_PATH) + statres = atloc.stat() + atloc_ep = self.enterContext(atloc.as_emptypath()) + self.assertTrue(atloc_ep.flags & linuxnamespaces.AtFlags.AT_EMPTY_PATH) + self.assertGreaterEqual(atloc_ep.fd, 0) + self.assertEqual(atloc_ep.location, "") + self.assertEqual(atloc_ep.stat().st_ino, statres.st_ino) + atloc_dup = self.enterContext(atloc_ep.as_emptypath()) + self.assertTrue( + atloc_dup.flags & linuxnamespaces.AtFlags.AT_EMPTY_PATH + ) + self.assertGreaterEqual(atloc_ep.fd, 0) + self.assertNotEqual(atloc_dup.fd, atloc_ep.fd) + self.assertEqual(atloc_dup.location, "") + self.assertEqual(atloc_dup.stat().st_ino, statres.st_ino) + @atloc_subtest(skip=("absent", "file", "symlink")) def test_join_mkdir(self, _: str, atloc: AtLocation) -> None: subdir = atloc / "subdir" |