stop using fcntl: not working on windows and line read not blocking posix

[CI SKIP]

Author: penguinolog

exec_helpers/subprocess_runner.py

@@ -19,9 +19,7 @@
 from __future__ import absolute_import
 from __future__ import unicode_literals
 
-import fcntl
 import logging
-import os
 import select
 import sys
 import subprocess  # nosec  # Expected usage
@@ -38,6 +36,7 @@
 from exec_helpers import proc_enums
 
 logger = logging.getLogger(__name__)
+
 _win = sys.platform == "win32"
 _type_exit_codes = typing.Union[int, proc_enums.ExitCodes]
 _type_expected = typing.Optional[typing.Iterable[_type_exit_codes]]
@@ -145,7 +144,7 @@ def poll_streams(
                             verbose=verbose
                         )
 
-        @threaded.threaded(started=True)
+        @threaded.threaded(started=True, daemon=True)
         def poll_pipes(
             proc,  # type: subprocess.Popen
             result,  # type: exec_result.ExecResult
@@ -157,16 +156,6 @@ def poll_pipes(
             :type result: exec_result.ExecResult
             :type stop: threading.Event
             """
-            # Get file descriptors for stdout and stderr streams
-            fd_stdout = proc.stdout.fileno()
-            fd_stderr = proc.stderr.fileno()
-            # Get flags of stdout and stderr streams
-            fl_stdout = fcntl.fcntl(fd_stdout, fcntl.F_GETFL)
-            fl_stderr = fcntl.fcntl(fd_stderr, fcntl.F_GETFL)
-            # Set nonblock mode for stdout and stderr streams
-            fcntl.fcntl(fd_stdout, fcntl.F_SETFL, fl_stdout | os.O_NONBLOCK)
-            fcntl.fcntl(fd_stderr, fcntl.F_SETFL, fl_stderr | os.O_NONBLOCK)
-
             while not stop.isSet():
                 time.sleep(0.1)
                 poll_streams(

test/test_subprocess_runner.py

@@ -51,7 +51,6 @@ def fileno(self):
 
 @mock.patch('exec_helpers.subprocess_runner.logger', autospec=True)
 @mock.patch('select.select', autospec=True)
-@mock.patch('fcntl.fcntl', autospec=True)
 @mock.patch('subprocess.Popen', autospec=True, name='subprocess.Popen')
 class TestSubprocessRunner(unittest.TestCase):
     @staticmethod
@@ -84,7 +83,7 @@ def gen_cmd_result_log_message(result):
         return (u"Command exit code '{code!s}':\n{cmd!s}\n"
                 .format(cmd=result.cmd.rstrip(), code=result.exit_code))
 
-    def test_call(self, popen, fcntl, select, logger):
+    def test_call(self, popen, select, logger):
         popen_obj, exp_result = self.prepare_close(popen)
         select.return_value = [popen_obj.stdout, popen_obj.stderr], [], []
 
@@ -130,7 +129,7 @@ def test_call(self, popen, fcntl, select, logger):
             mock.call.poll(), popen_obj.mock_calls
         )
 
-    def test_call_verbose(self, popen, fcntl, select, logger):
+    def test_call_verbose(self, popen, select, logger):
         popen_obj, _ = self.prepare_close(popen)
         select.return_value = [popen_obj.stdout, popen_obj.stderr], [], []