utils.py 文件源码

def _processStreams(self):
        if len(self._closedfds) == 3:
            return

        if not self._streamLock.acquire(False):
            self._streamLock.acquire()
            self._streamLock.release()
            return
        try:
            if self._stdin.len > 0 and self._stdin.pos == 0:
                # Polling stdin is redundant if there is nothing to write
                # turn on only if data is waiting to be pushed
                self._poller.modify(self._fdin, select.EPOLLOUT)

            pollres = NoIntrPoll(self._poller.poll, 1)

            for fd, event in pollres:
                stream = self._fdMap[fd]
                if event & select.EPOLLOUT and self._stdin.len > 0:
                    buff = self._stdin.read(BUFFSIZE)
                    written = os.write(fd, buff)
                    stream.pos -= len(buff) - written
                    if stream.pos == stream.len:
                        stream.truncate(0)
                        self._poller.modify(fd, 0)

                elif event & (select.EPOLLIN | select.EPOLLPRI):
                    data = os.read(fd, BUFFSIZE)
                    oldpos = stream.pos
                    stream.pos = stream.len
                    stream.write(data)
                    stream.pos = oldpos

                elif event & (select.EPOLLHUP | select.EPOLLERR):
                    self._poller.unregister(fd)
                    self._closedfds.append(fd)
                    # I don't close the fd because the original Popen
                    # will do it.

            if self.stdin.closed and self._fdin not in self._closedfds:
                self._poller.unregister(self._fdin)
                self._closedfds.append(self._fdin)
                self._proc.stdin.close()

        finally:
            self._streamLock.release()