Do not use a pseudo-terminal in command_executer.
Using a psuedo-terminal causes problems when running jobs through cron. Gentoo's
sandbox aborts builds due to a write violation to /dev/ptmx. Longer term
Gentoo's sandbox may need to add /dev/ptmx to the whitelist.
BUG=none
TEST=python no_pseudo_terminal_test.py passes.
Change-Id: I2ac00718a4694f097fcec8bcf2cc95d48bdd9e51
Reviewed-on: https://gerrit-int.chromium.org/37323
Reviewed-by: Bhaskar Janakiraman <bjanakiraman@google.com>
Commit-Queue: asharif <asharif@google.com>
Tested-by: asharif <asharif@google.com>
diff --git a/utils/command_executer.py b/utils/command_executer.py
index 0aedc47..a4dca64 100644
--- a/utils/command_executer.py
+++ b/utils/command_executer.py
@@ -5,7 +5,6 @@
import getpass
import os
-import pty
import re
import select
import subprocess
@@ -62,10 +61,9 @@
user = username + "@"
cmd = "ssh -t -t %s%s -- '%s'" % (user, machine, cmd)
- pty_fds = pty.openpty()
p = subprocess.Popen(cmd, stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
- stdin=pty_fds[0], shell=True)
+ shell=True)
full_stdout = ""
full_stderr = ""
@@ -135,8 +133,6 @@
break
p.wait()
- os.close(pty_fds[0])
- os.close(pty_fds[1])
if return_output:
return (p.returncode, full_stdout, full_stderr)
return p.returncode
diff --git a/utils/no_pseudo_terminal_test.py b/utils/no_pseudo_terminal_test.py
new file mode 100644
index 0000000..c4c3c43
--- /dev/null
+++ b/utils/no_pseudo_terminal_test.py
@@ -0,0 +1,49 @@
+"""Test to ensure we're not touching /dev/ptmx when running commands."""
+
+import os
+import subprocess
+import tempfile
+import time
+import unittest
+from utils import command_executer
+
+
+class NoPsuedoTerminalTest(unittest.TestCase):
+
+ STRACE_TIMEOUT = 10
+
+ def _AttachStraceToSelf(self, output_file):
+ """Attaches strace to the current process."""
+ args = ["strace", "-o", output_file, "-p", str(os.getpid())]
+ print args
+ self._strace_process = subprocess.Popen(args)
+ # Wait until we see some activity.
+ start_time = time.time()
+ while time.time() - start_time < self.STRACE_TIMEOUT:
+ if os.path.isfile(output_file) and open(output_file).read(1):
+ return True
+ time.sleep(1)
+ return False
+
+ def _KillStraceProcess(self):
+ """Kills strace that was started by _AttachStraceToSelf()."""
+ self._strace_process.terminate()
+ self._strace_process.wait()
+ return True
+
+ def testNoPseudoTerminalWhenRunningCommand(self):
+ """Test to make sure we're not touching /dev/ptmx when running commands."""
+ temp_file = tempfile.mktemp()
+ self.assertTrue(self._AttachStraceToSelf(temp_file))
+
+ ce = command_executer.GetCommandExecuter()
+ ce.RunCommand("echo")
+
+ self.assertTrue(self._KillStraceProcess())
+
+ strace_contents = open(temp_file).read()
+ self.assertFalse("/dev/ptmx" in strace_contents)
+
+
+if __name__ == '__main__':
+ unittest.main()
