diff options
Diffstat (limited to 'Lib/subprocess.py')
| -rw-r--r-- | Lib/subprocess.py | 85 |
1 files changed, 72 insertions, 13 deletions
diff --git a/Lib/subprocess.py b/Lib/subprocess.py index db6342f..f69159e 100644 --- a/Lib/subprocess.py +++ b/Lib/subprocess.py @@ -304,9 +304,9 @@ def call(*popenargs, timeout=None, **kwargs): with Popen(*popenargs, **kwargs) as p: try: return p.wait(timeout=timeout) - except: + except: # Including KeyboardInterrupt, wait handled that. p.kill() - p.wait() + # We don't call p.wait() again as p.__exit__ does that for us. raise @@ -450,9 +450,9 @@ def run(*popenargs, input=None, timeout=None, check=False, **kwargs): stdout, stderr = process.communicate() raise TimeoutExpired(process.args, timeout, output=stdout, stderr=stderr) - except: + except: # Including KeyboardInterrupt, communicate handled that. process.kill() - process.wait() + # We don't call process.wait() as .__exit__ does that for us. raise retcode = process.poll() if check and retcode: @@ -714,6 +714,11 @@ class Popen(object): self.text_mode = encoding or errors or text or universal_newlines + # How long to resume waiting on a child after the first ^C. + # There is no right value for this. The purpose is to be polite + # yet remain good for interactive users trying to exit a tool. + self._sigint_wait_secs = 0.25 # 1/xkcd221.getRandomNumber() + self._closed_child_pipe_fds = False try: @@ -787,7 +792,7 @@ class Popen(object): def __enter__(self): return self - def __exit__(self, type, value, traceback): + def __exit__(self, exc_type, value, traceback): if self.stdout: self.stdout.close() if self.stderr: @@ -796,6 +801,22 @@ class Popen(object): if self.stdin: self.stdin.close() finally: + if exc_type == KeyboardInterrupt: + # https://bugs.python.org/issue25942 + # In the case of a KeyboardInterrupt we assume the SIGINT + # was also already sent to our child processes. We can't + # block indefinitely as that is not user friendly. + # If we have not already waited a brief amount of time in + # an interrupted .wait() or .communicate() call, do so here + # for consistency. + if self._sigint_wait_secs > 0: + try: + self._wait(timeout=self._sigint_wait_secs) + except TimeoutExpired: + pass + self._sigint_wait_secs = 0 # Note that this has been done. + return # resume the KeyboardInterrupt + # Wait for the process to terminate, to avoid zombies. self.wait() @@ -804,7 +825,7 @@ class Popen(object): # We didn't get to successfully create a child process. return if self.returncode is None: - # Not reading subprocess exit status creates a zombi process which + # Not reading subprocess exit status creates a zombie process which # is only destroyed at the parent python process exit _warn("subprocess %s is still running" % self.pid, ResourceWarning, source=self) @@ -889,6 +910,21 @@ class Popen(object): try: stdout, stderr = self._communicate(input, endtime, timeout) + except KeyboardInterrupt: + # https://bugs.python.org/issue25942 + # See the detailed comment in .wait(). + if timeout is not None: + sigint_timeout = min(self._sigint_wait_secs, + self._remaining_time(endtime)) + else: + sigint_timeout = self._sigint_wait_secs + self._sigint_wait_secs = 0 # nothing else should wait. + try: + self._wait(timeout=sigint_timeout) + except TimeoutExpired: + pass + raise # resume the KeyboardInterrupt + finally: self._communication_started = True @@ -919,6 +955,30 @@ class Popen(object): raise TimeoutExpired(self.args, orig_timeout) + def wait(self, timeout=None): + """Wait for child process to terminate; returns self.returncode.""" + if timeout is not None: + endtime = _time() + timeout + try: + return self._wait(timeout=timeout) + except KeyboardInterrupt: + # https://bugs.python.org/issue25942 + # The first keyboard interrupt waits briefly for the child to + # exit under the common assumption that it also received the ^C + # generated SIGINT and will exit rapidly. + if timeout is not None: + sigint_timeout = min(self._sigint_wait_secs, + self._remaining_time(endtime)) + else: + sigint_timeout = self._sigint_wait_secs + self._sigint_wait_secs = 0 # nothing else should wait. + try: + self._wait(timeout=sigint_timeout) + except TimeoutExpired: + pass + raise # resume the KeyboardInterrupt + + if _mswindows: # # Windows methods @@ -1127,16 +1187,16 @@ class Popen(object): return self.returncode - def wait(self, timeout=None): - """Wait for child process to terminate. Returns returncode - attribute.""" + def _wait(self, timeout): + """Internal implementation of wait() on Windows.""" if timeout is None: timeout_millis = _winapi.INFINITE else: timeout_millis = int(timeout * 1000) if self.returncode is None: + # API note: Returns immediately if timeout_millis == 0. result = _winapi.WaitForSingleObject(self._handle, - timeout_millis) + timeout_millis) if result == _winapi.WAIT_TIMEOUT: raise TimeoutExpired(self.args, timeout) self.returncode = _winapi.GetExitCodeProcess(self._handle) @@ -1498,9 +1558,8 @@ class Popen(object): return (pid, sts) - def wait(self, timeout=None): - """Wait for child process to terminate. Returns returncode - attribute.""" + def _wait(self, timeout): + """Internal implementation of wait() on POSIX.""" if self.returncode is not None: return self.returncode |