Merged revisions 78527,78531 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r78527 | gregory.p.smith | 2010-02-28 17:22:39 -0800 (Sun, 28 Feb 2010) | 4 lines
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.
........
r78531 | gregory.p.smith | 2010-02-28 18:31:33 -0800 (Sun, 28 Feb 2010) | 2 lines
Fix for r78527. It left out updating forkpty.
........
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 @@
from test import test_support
import thread
import time
+import sys
from test import lock_tests
@@ -169,8 +170,47 @@
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()
diff --git a/Misc/NEWS b/Misc/NEWS
index b05b854..f71e9be 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -250,6 +250,10 @@
- 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 @@
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 @@
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 @@
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 @@
}
/* 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