# Source code for pexpect.socket_pexpect

    """This is like :mod:`pexpect`, but it will work with any socket that you
    pass it. You are responsible for opening and closing the socket.

    PEXPECT LICENSE

        This license is approved by the OSI and FSF as GPL-compatible.
            http://opensource.org/licenses/isc-license.txt

        Copyright (c) 2012, Noah Spurrier <noah@noah.org>
        PERMISSION TO USE, COPY, MODIFY, AND/OR DISTRIBUTE THIS SOFTWARE FOR ANY
        PURPOSE WITH OR WITHOUT FEE IS HEREBY GRANTED, PROVIDED THAT THE ABOVE
        COPYRIGHT NOTICE AND THIS PERMISSION NOTICE APPEAR IN ALL COPIES.
        THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
        WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
        MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
        ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
        WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
        ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
        OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

    """

    import socket
    from contextlib import contextmanager

    from .exceptions import TIMEOUT, EOF
    from .spawnbase import SpawnBase

    __all__ = ["SocketSpawn"]

    class SocketSpawn(SpawnBase):
        """This is like :mod:`pexpect.fdpexpect` but uses the cross-platform python socket api,
        rather than the unix-specific file descriptor api. Thus, it works with
        remote connections on both unix and windows."""

        def __init__(
            self,
            socket: socket.socket,
            args=None,
            timeout=30,
            maxread=2000,
            searchwindowsize=None,
            logfile=None,
            encoding=None,
            codec_errors="strict",
            use_poll=False,
        ):
            """This takes an open socket."""

            self.args = None
            self.command = None
            SpawnBase.__init__(
                self,
                timeout,
                maxread,
                searchwindowsize,
                logfile,
                encoding=encoding,
                codec_errors=codec_errors,
            )
            self.socket = socket
            self.child_fd = socket.fileno()
            self.closed = False
            self.name = "<socket %s>" % socket
            self.use_poll = use_poll

        def close(self):
            """Close the socket.

            Calling this method a second time does nothing, but if the file
            descriptor was closed elsewhere, :class:`OSError` will be raised.
            """
            if self.child_fd == -1:
                return

            self.flush()
            self.socket.shutdown(socket.SHUT_RDWR)
            self.socket.close()
            self.child_fd = -1
            self.closed = True

        def isalive(self):
            """ Alive if the fileno is valid """
            return self.socket.fileno() >= 0

        def send(self, s) -> int:
            """Write to socket, return number of bytes written"""
            s = self._coerce_send_string(s)
            self._log(s, "send")

            b = self._encoder.encode(s, final=False)
            self.socket.sendall(b)
            return len(b)

        def sendline(self, s) -> int:
            """Write to socket with trailing newline, return number of bytes written"""
            s = self._coerce_send_string(s)
            return self.send(s + self.linesep)

        def write(self, s):
            """Write to socket, return None"""
            self.send(s)

        def writelines(self, sequence):
            "Call self.write() for each item in sequence"
            for s in sequence:
                self.write(s)

        @contextmanager
        def _timeout(self, timeout):
            saved_timeout = self.socket.gettimeout()
            try:
                self.socket.settimeout(timeout)
                yield
            finally:
                self.socket.settimeout(saved_timeout)

        def read_nonblocking(self, size=1, timeout=-1):
            """
            Read from the file descriptor and return the result as a string.

            The read_nonblocking method of :class:`SpawnBase` assumes that a call
            to os.read will not block (timeout parameter is ignored). This is not
            the case for POSIX file-like objects such as sockets and serial ports.

            Use :func:`select.select`, timeout is implemented conditionally for
            POSIX systems.

            :param int size: Read at most *size* bytes.
            :param int timeout: Wait timeout seconds for file descriptor to be
                ready to read. When -1 (default), use self.timeout. When 0, poll.
            :return: String containing the bytes read
            """
            if timeout == -1:
                timeout = self.timeout
            try:
                with self._timeout(timeout):
                    s = self.socket.recv(size)
                    if s == b'':
                        self.flag_eof = True
                        raise EOF("Socket closed")
                    return s
            except socket.timeout:
                raise TIMEOUT("Timeout exceeded.")