lib/sqlcmd/sqlcmd/ecmd.py

#!/usr/bin/env python
# -*- coding: iso-8859-1 -*-
#
# $Id: 4924bbb91e59566666746c62bd76c59e178b4b6a $

"""
Configuration classes for *sqlcmd*.

COPYRIGHT AND LICENSE

Copyright © 2008 Brian M. Clapper

This is free software, released under the following BSD-like license:

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice,
   this list of conditions and the following disclaimer.

2. The end-user documentation included with the redistribution, if any,
   must include the following acknowlegement:

      This product includes software developed by Brian M. Clapper
      (bmc@clapper.org, http://www.clapper.org/bmc/). That software is
      copyright © 2008 Brian M. Clapper.

    Alternately, this acknowlegement may appear in the software itself, if
    and wherever such third-party acknowlegements normally appear.

THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
EVENT SHALL BRIAN M. CLAPPER BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

$Id: 4924bbb91e59566666746c62bd76c59e178b4b6a $
"""

# ---------------------------------------------------------------------------
# Imports
# ---------------------------------------------------------------------------

from cmd import Cmd
import logging
import os
import sys

# ---------------------------------------------------------------------------
# Exports
# ---------------------------------------------------------------------------

__all__ = ['ECmd']

# ---------------------------------------------------------------------------
# Constants
# ---------------------------------------------------------------------------

# ---------------------------------------------------------------------------
# Globals
# ---------------------------------------------------------------------------

log = logging.getLogger('sqlcmd.ecmd')

# ---------------------------------------------------------------------------
# Classes
# ---------------------------------------------------------------------------

class ECmd(Cmd):
    """
    Slightly enhanced version of ``cmd.Cmd`` that changes the command loop
    a little to handle SIGINT more appropriately.
    """
    def __init__(self, completekey='tab', stdin=None, stdout=None):
        """
        Instantiate a line-oriented interpreter framework.

        The optional argument 'completekey' is the readline name of a
        completion key; it defaults to the Tab key. If completekey is
        not None and the readline module is available, command completion
        is done automatically. The optional arguments stdin and stdout
        specify alternate input and output file objects; if not specified,
        sys.stdin and sys.stdout are used.

        """
        Cmd.__init__(self, completekey, stdin, stdout)

    def interrupted(self):
        """
        Called by ``cmdloop`` on interrupt.
        """
        pass

    def cmdloop(self, intro=None):
        """
        Repeatedly issue a prompt, accept input, parse an initial prefix
        off the received input, and dispatch to action methods, passing them
        the remainder of the line as argument.

        This version is a direct rip-off of the parent class's ``cmdloop()``
        method, with some changes to support SIGINT properly.
        """
        self.preloop()
        if self.use_rawinput and self.completekey:
            try:
                import readline
                self.old_completer = readline.get_completer()
                readline.set_completer(self.complete)
                readline.parse_and_bind(self.completekey+": complete")
            except ImportError:
                pass
        try:
            if intro is not None:
                self.intro = intro
            if self.intro:
                self.stdout.write(str(self.intro)+"\n")
            stop = None
            while not stop:
                try:
                    if self.cmdqueue:
                        line = self.cmdqueue.pop(0)
                    else:
                        line = self.get_input(self.prompt)

                    line = self.precmd(line)
                    stop = self.onecmd(line)
                    stop = self.postcmd(stop, line)
                except KeyboardInterrupt:
                    self.interrupted()

            self.postloop()
        finally:
            if self.use_rawinput and self.completekey:
                try:
                    import readline
                    readline.set_completer(self.old_completer)
                except ImportError:
                    pass

    def get_input(self, prompt):
        if self.use_rawinput:
            try:
                line = raw_input(self.prompt)
            except EOFError:
                line = 'EOF'
        else:
            self.stdout.write(self.prompt)
            self.stdout.flush()
            line = self.stdin.readline()
            if not len(line):
                line = 'EOF'
            else:
                line = line[:-1] # chop \n

        return line