diff options
| -rw-r--r-- | Doc/library/fcntl.rst | 5 | ||||
| -rw-r--r-- | Doc/library/subprocess.rst | 10 | ||||
| -rw-r--r-- | Lib/subprocess.py | 19 | ||||
| -rw-r--r-- | Lib/test/test_fcntl.py | 13 | ||||
| -rw-r--r-- | Lib/test/test_subprocess.py | 47 | ||||
| -rw-r--r-- | Misc/ACKS | 1 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2020-08-19-08-32-13.bpo-41586.IYjmjK.rst | 2 | ||||
| -rw-r--r-- | Modules/fcntlmodule.c | 8 |
8 files changed, 102 insertions, 3 deletions
diff --git a/Doc/library/fcntl.rst b/Doc/library/fcntl.rst index 07a15d2..9d80211 100644 --- a/Doc/library/fcntl.rst +++ b/Doc/library/fcntl.rst @@ -39,6 +39,11 @@ descriptor. On Linux(>=3.15), the fcntl module exposes the ``F_OFD_GETLK``, ``F_OFD_SETLK`` and ``F_OFD_SETLKW`` constants, which working with open file description locks. +.. versionchanged:: 3.10 + On Linux >= 2.6.11, the fcntl module exposes the ``F_GETPIPE_SZ`` and + ``F_SETPIPE_SZ`` constants, which allow to check and modify a pipe's size + respectively. + The module defines the following functions: diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst index e37cc98..7993b10 100644 --- a/Doc/library/subprocess.rst +++ b/Doc/library/subprocess.rst @@ -341,7 +341,7 @@ functions. startupinfo=None, creationflags=0, restore_signals=True, \ start_new_session=False, pass_fds=(), \*, group=None, \ extra_groups=None, user=None, umask=-1, \ - encoding=None, errors=None, text=None) + encoding=None, errors=None, text=None, pipesize=-1) Execute a child program in a new process. On POSIX, the class uses :meth:`os.execvp`-like behavior to execute the child program. On Windows, @@ -625,6 +625,14 @@ functions. * :data:`CREATE_DEFAULT_ERROR_MODE` * :data:`CREATE_BREAKAWAY_FROM_JOB` + *pipesize* can be used to change the size of the pipe when + :data:`PIPE` is used for *stdin*, *stdout* or *stderr*. The size of the pipe + is only changed on platforms that support this (only Linux at this time of + writing). Other platforms will ignore this parameter. + + .. versionadded:: 3.10 + The ``pipesize`` parameter was added. + Popen objects are supported as context managers via the :keyword:`with` statement: on exit, standard file descriptors are closed, and the process is waited for. :: diff --git a/Lib/subprocess.py b/Lib/subprocess.py index 86fdf27..6a6c2fc 100644 --- a/Lib/subprocess.py +++ b/Lib/subprocess.py @@ -62,6 +62,11 @@ try: import grp except ImportError: grp = None +try: + import fcntl +except ImportError: + fcntl = None + __all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call", "getstatusoutput", "getoutput", "check_output", "run", "CalledProcessError", "DEVNULL", @@ -756,7 +761,7 @@ class Popen(object): startupinfo=None, creationflags=0, restore_signals=True, start_new_session=False, pass_fds=(), *, user=None, group=None, extra_groups=None, - encoding=None, errors=None, text=None, umask=-1): + encoding=None, errors=None, text=None, umask=-1, pipesize=-1): """Create new Popen instance.""" _cleanup() # Held while anything is calling waitpid before returncode has been @@ -773,6 +778,11 @@ class Popen(object): if not isinstance(bufsize, int): raise TypeError("bufsize must be an integer") + if pipesize is None: + pipesize = -1 # Restore default + if not isinstance(pipesize, int): + raise TypeError("pipesize must be an integer") + if _mswindows: if preexec_fn is not None: raise ValueError("preexec_fn is not supported on Windows " @@ -797,6 +807,7 @@ class Popen(object): self.returncode = None self.encoding = encoding self.errors = errors + self.pipesize = pipesize # Validate the combinations of text and universal_newlines if (text is not None and universal_newlines is not None @@ -1575,6 +1586,8 @@ class Popen(object): pass elif stdin == PIPE: p2cread, p2cwrite = os.pipe() + if self.pipesize > 0 and hasattr(fcntl, "F_SETPIPE_SZ"): + fcntl.fcntl(p2cwrite, fcntl.F_SETPIPE_SZ, self.pipesize) elif stdin == DEVNULL: p2cread = self._get_devnull() elif isinstance(stdin, int): @@ -1587,6 +1600,8 @@ class Popen(object): pass elif stdout == PIPE: c2pread, c2pwrite = os.pipe() + if self.pipesize > 0 and hasattr(fcntl, "F_SETPIPE_SZ"): + fcntl.fcntl(c2pwrite, fcntl.F_SETPIPE_SZ, self.pipesize) elif stdout == DEVNULL: c2pwrite = self._get_devnull() elif isinstance(stdout, int): @@ -1599,6 +1614,8 @@ class Popen(object): pass elif stderr == PIPE: errread, errwrite = os.pipe() + if self.pipesize > 0 and hasattr(fcntl, "F_SETPIPE_SZ"): + fcntl.fcntl(errwrite, fcntl.F_SETPIPE_SZ, self.pipesize) elif stderr == STDOUT: if c2pwrite != -1: errwrite = c2pwrite diff --git a/Lib/test/test_fcntl.py b/Lib/test/test_fcntl.py index 7e10920..8d6e9ff 100644 --- a/Lib/test/test_fcntl.py +++ b/Lib/test/test_fcntl.py @@ -190,6 +190,19 @@ class TestFcntl(unittest.TestCase): res = fcntl.fcntl(self.f.fileno(), fcntl.F_GETPATH, bytes(len(expected))) self.assertEqual(expected, res) + @unittest.skipIf(not (hasattr(fcntl, "F_SETPIPE_SZ") and hasattr(fcntl, "F_GETPIPE_SZ")), + "F_SETPIPE_SZ and F_GETPIPE_SZ are not available on all unix platforms.") + def test_fcntl_f_pipesize(self): + test_pipe_r, test_pipe_w = os.pipe() + # Get the default pipesize with F_GETPIPE_SZ + pipesize_default = fcntl.fcntl(test_pipe_w, fcntl.F_GETPIPE_SZ) + # Multiply the default with 2 to get a new value. + fcntl.fcntl(test_pipe_w, fcntl.F_SETPIPE_SZ, pipesize_default * 2) + self.assertEqual(fcntl.fcntl(test_pipe_w, fcntl.F_GETPIPE_SZ), pipesize_default * 2) + os.close(test_pipe_r) + os.close(test_pipe_w) + + def test_main(): run_unittest(TestFcntl) diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py index 434ba56..8b576c0 100644 --- a/Lib/test/test_subprocess.py +++ b/Lib/test/test_subprocess.py @@ -39,6 +39,11 @@ try: except ImportError: grp = None +try: + import fcntl +except: + fcntl = None + if support.PGO: raise unittest.SkipTest("test is not helpful for PGO") @@ -661,6 +666,46 @@ class ProcessTestCase(BaseTestCase): p.wait() self.assertEqual(p.stdin, None) + def test_pipesizes(self): + # stdin redirection + pipesize = 16 * 1024 + p = subprocess.Popen([sys.executable, "-c", + 'import sys; sys.stdin.read(); sys.stdout.write("out"); sys.stderr.write("error!")'], + stdin=subprocess.PIPE, + stdout=subprocess.PIPE, + stderr=subprocess.PIPE, + pipesize=pipesize) + # We only assert pipe size has changed on platforms that support it. + if sys.platform != "win32" and hasattr(fcntl, "F_GETPIPE_SZ"): + for fifo in [p.stdin, p.stdout, p.stderr]: + self.assertEqual(fcntl.fcntl(fifo.fileno(), fcntl.F_GETPIPE_SZ), pipesize) + # Windows pipe size can be acquired with the GetNamedPipeInfoFunction + # https://docs.microsoft.com/en-us/windows/win32/api/namedpipeapi/nf-namedpipeapi-getnamedpipeinfo + # However, this function is not yet in _winapi. + p.stdin.write(b"pear") + p.stdin.close() + p.wait() + + def test_pipesize_default(self): + p = subprocess.Popen([sys.executable, "-c", + 'import sys; sys.stdin.read(); sys.stdout.write("out");' + ' sys.stderr.write("error!")'], + stdin=subprocess.PIPE, + stdout=subprocess.PIPE, + stderr=subprocess.PIPE, + pipesize=-1) + # UNIX tests using fcntl + if sys.platform != "win32" and hasattr(fcntl, "F_GETPIPE_SZ"): + fp_r, fp_w = os.pipe() + default_pipesize = fcntl.fcntl(fp_w, fcntl.F_GETPIPE_SZ) + for fifo in [p.stdin, p.stdout, p.stderr]: + self.assertEqual( + fcntl.fcntl(fifo.fileno(), fcntl.F_GETPIPE_SZ), default_pipesize) + # On other platforms we cannot test the pipe size (yet). But above code + # using pipesize=-1 should not crash. + p.stdin.close() + p.wait() + def test_env(self): newenv = os.environ.copy() newenv["FRUIT"] = "orange" @@ -3503,7 +3548,7 @@ class MiscTests(unittest.TestCase): def test__all__(self): """Ensure that __all__ is populated properly.""" - intentionally_excluded = {"list2cmdline", "Handle", "pwd", "grp"} + intentionally_excluded = {"list2cmdline", "Handle", "pwd", "grp", "fcntl"} exported = set(subprocess.__all__) possible_exports = set() import types @@ -1818,6 +1818,7 @@ Johannes Vogel Michael Vogt Radu Voicilas Alex Volkov +Ruben Vorderman Guido Vranken Martijn Vries Sjoerd de Vries diff --git a/Misc/NEWS.d/next/Library/2020-08-19-08-32-13.bpo-41586.IYjmjK.rst b/Misc/NEWS.d/next/Library/2020-08-19-08-32-13.bpo-41586.IYjmjK.rst new file mode 100644 index 0000000..4046167 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-08-19-08-32-13.bpo-41586.IYjmjK.rst @@ -0,0 +1,2 @@ +Add F_SETPIPE_SZ and F_GETPIPE_SZ to fcntl module. Allow setting pipesize on +subprocess.Popen. diff --git a/Modules/fcntlmodule.c b/Modules/fcntlmodule.c index afd2810..cdf0f9b 100644 --- a/Modules/fcntlmodule.c +++ b/Modules/fcntlmodule.c @@ -565,6 +565,14 @@ all_ins(PyObject* m) if (PyModule_AddIntMacro(m, F_SHLCK)) return -1; #endif +/* Linux specifics */ +#ifdef F_SETPIPE_SZ + if (PyModule_AddIntMacro(m, F_SETPIPE_SZ)) return -1; +#endif +#ifdef F_GETPIPE_SZ + if (PyModule_AddIntMacro(m, F_GETPIPE_SZ)) return -1; +#endif + /* OS X specifics */ #ifdef F_FULLFSYNC if (PyModule_AddIntMacro(m, F_FULLFSYNC)) return -1; |