Fix race on subprocess.Popen return values.

This fixes:
https://llvm.org/bugs/show_bug.cgi?id=25019

llvm-svn: 249182

2 files changed, 49 insertions, 1 deletions

diff --git a/lldb/test/test_runner/lib/process_control.py b/lldb/test/test_runner/lib/process_control.py
index 9a788665d27..ba30840147e 100644
--- a/lldb/test/test_runner/lib/process_control.py
+++ b/lldb/test/test_runner/lib/process_control.py
@@ -611,3 +611,48 @@ class ProcessDriver(object):
             self.io_thread.output,
             not completed_normally,
             self.returncode)
+
+
+def patched_init(self, *args, **kwargs):
+    self.original_init(*args, **kwargs)
+    # Initialize our condition variable that protects wait()/poll().
+    self.wait_condition = threading.Condition()
+
+
+def patched_wait(self):
+    self.wait_condition.acquire()
+    try:
+        result = self.original_wait()
+        # The process finished.  Signal the condition.
+        self.wait_condition.notify_all()
+        return result
+    finally:
+        self.wait_condition.release()
+
+
+def patched_poll(self):
+    self.wait_condition.acquire()
+    try:
+        result = self.original_poll()
+        if self.returncode is not None:
+            # We did complete, and we have the return value.
+            # Signal the event to indicate we're done.
+            self.wait_condition.notify_all()
+        return result
+    finally:
+        self.wait_condition.release()
+
+
+def patch_up_subprocess_popen():
+    subprocess.Popen.original_init = subprocess.Popen.__init__
+    subprocess.Popen.__init__ = patched_init
+
+    subprocess.Popen.original_wait = subprocess.Popen.wait
+    subprocess.Popen.wait = patched_wait
+
+    subprocess.Popen.original_poll = subprocess.Popen.poll
+    subprocess.Popen.poll = patched_poll
+
+# Replace key subprocess.Popen() threading-unprotected methods with
+# threading-protected versions.
+patch_up_subprocess_popen()
diff --git a/lldb/test/test_runner/test/process_control_tests.py b/lldb/test/test_runner/test/process_control_tests.py
index 6eddd386b03..354506d6581 100644
--- a/lldb/test/test_runner/test/process_control_tests.py
+++ b/lldb/test/test_runner/test/process_control_tests.py
@@ -202,6 +202,9 @@ class ProcessControlTimeoutTests(ProcessControlTests):
         """inferior exit detected when inferior children are live with shared
         stdout/stderr handles.
         """
+        # Requires review D13362 or equivalent to be implemented.
+        self.skipTest("http://reviews.llvm.org/D13362")
+
         driver = TestInferiorDriver()
 
         # Create the inferior (I1), and instruct it to create a child (C1)
@@ -220,7 +223,7 @@ class ProcessControlTimeoutTests(ProcessControlTests):
             "process failed to complete")
 
         # Ensure we didn't receive a timeout.
-        self.assertTrue(
+        self.assertFalse(
             driver.was_timeout, "inferior should have completed normally")
 
         self.assertEqual(