diff options
| -rw-r--r-- | Lib/test/test_thread.py | 42 | ||||
| -rw-r--r-- | Misc/NEWS | 4 | ||||
| -rw-r--r-- | Modules/posixmodule.c | 36 | ||||
| -rw-r--r-- | Python/import.c | 12 |
4 files changed, 76 insertions, 18 deletions
diff --git a/Lib/test/test_thread.py b/Lib/test/test_thread.py index 8bbfdb1..8dd8d1e 100644 --- a/Lib/test/test_thread.py +++ b/Lib/test/test_thread.py @@ -4,6 +4,7 @@ import random from test import test_support import thread import time +import sys from test import lock_tests @@ -169,8 +170,47 @@ class LockTests(lock_tests.LockTests): locktype = thread.allocate_lock +class TestForkInThread(unittest.TestCase): + def setUp(self): + self.read_fd, self.write_fd = os.pipe() + + def test_forkinthread(self): + if sys.platform.startswith('win'): + from test.test_support import TestSkipped + raise TestSkipped("This test is only appropriate for " + "POSIX-like systems.") + def thread1(): + try: + pid = os.fork() # fork in a thread + except RuntimeError: + sys.exit(0) # exit the child + + if pid == 0: # child + os.close(self.read_fd) + os.write(self.write_fd, "OK") + sys.exit(0) + else: # parent + os.close(self.write_fd) + + thread.start_new_thread(thread1, ()) + self.assertEqual(os.read(self.read_fd, 2), "OK", + "Unable to fork() in thread") + + def tearDown(self): + try: + os.close(self.read_fd) + except OSError: + pass + + try: + os.close(self.write_fd) + except OSError: + pass + + def test_main(): - test_support.run_unittest(ThreadRunningTests, BarrierTest, LockTests) + test_support.run_unittest(ThreadRunningTests, BarrierTest, LockTests, + TestForkInThread) if __name__ == "__main__": test_main() @@ -250,6 +250,10 @@ Extension Modules - Expat: Fix DoS via XML document with malformed UTF-8 sequences (CVE_2009_3560). +- Issue #7242: On Solaris 9 and earlier calling os.fork() from within a + thread could raise an incorrect RuntimeError about not holding the import + lock. The import lock is now reinitialized after fork. + Build ----- diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c index 616722f..50ef803 100644 --- a/Modules/posixmodule.c +++ b/Modules/posixmodule.c @@ -3632,14 +3632,18 @@ static PyObject * posix_fork1(PyObject *self, PyObject *noargs) { pid_t pid; - int result; + int result = 0; _PyImport_AcquireLock(); pid = fork1(); - result = _PyImport_ReleaseLock(); + if (pid == 0) { + /* child: this clobbers and resets the import lock. */ + PyOS_AfterFork(); + } else { + /* parent: release the import lock. */ + result = _PyImport_ReleaseLock(); + } if (pid == -1) return posix_error(); - if (pid == 0) - PyOS_AfterFork(); if (result < 0) { /* Don't clobber the OSError if the fork failed. */ PyErr_SetString(PyExc_RuntimeError, @@ -3661,14 +3665,18 @@ static PyObject * posix_fork(PyObject *self, PyObject *noargs) { pid_t pid; - int result; + int result = 0; _PyImport_AcquireLock(); pid = fork(); - result = _PyImport_ReleaseLock(); + if (pid == 0) { + /* child: this clobbers and resets the import lock. */ + PyOS_AfterFork(); + } else { + /* parent: release the import lock. */ + result = _PyImport_ReleaseLock(); + } if (pid == -1) return posix_error(); - if (pid == 0) - PyOS_AfterFork(); if (result < 0) { /* Don't clobber the OSError if the fork failed. */ PyErr_SetString(PyExc_RuntimeError, @@ -3777,16 +3785,20 @@ To both, return fd of newly opened pseudo-terminal.\n"); static PyObject * posix_forkpty(PyObject *self, PyObject *noargs) { - int master_fd = -1, result; + int master_fd = -1, result = 0; pid_t pid; _PyImport_AcquireLock(); pid = forkpty(&master_fd, NULL, NULL, NULL); - result = _PyImport_ReleaseLock(); + if (pid == 0) { + /* child: this clobbers and resets the import lock. */ + PyOS_AfterFork(); + } else { + /* parent: release the import lock. */ + result = _PyImport_ReleaseLock(); + } if (pid == -1) return posix_error(); - if (pid == 0) - PyOS_AfterFork(); if (result < 0) { /* Don't clobber the OSError if the fork failed. */ PyErr_SetString(PyExc_RuntimeError, diff --git a/Python/import.c b/Python/import.c index cbfb761..43eabb8 100644 --- a/Python/import.c +++ b/Python/import.c @@ -298,15 +298,17 @@ _PyImport_ReleaseLock(void) } /* This function is called from PyOS_AfterFork to ensure that newly - created child processes do not share locks with the parent. */ + created child processes do not share locks with the parent. + We now acquire the import lock around fork() calls but on some platforms + (Solaris 9 and earlier? see isue7242) that still left us with problems. */ void _PyImport_ReInitLock(void) { -#ifdef _AIX - if (import_lock != NULL) - import_lock = PyThread_allocate_lock(); -#endif + if (import_lock != NULL) + import_lock = PyThread_allocate_lock(); + import_lock_thread = -1; + import_lock_level = 0; } #endif |