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"""Utilities to get a password and/or the current user name.
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getpass(prompt[, stream]) - Prompt for a password, with echo turned off.
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getuser() - Get the user name from the environment or password database.
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GetPassWarning - This UserWarning is issued when getpass() cannot prevent
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echoing of the password contents while reading.
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On Windows, the msvcrt module will be used.
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On the Mac EasyDialogs.AskPassword is used, if available.
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# Authors: Piers Lauder (original)
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# Guido van Rossum (Windows support and cleanup)
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# Gregory P. Smith (tty support & GetPassWarning)
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import os, sys, warnings
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__all__ = ["getpass","getuser","GetPassWarning"]
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class GetPassWarning(UserWarning): pass
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def unix_getpass(prompt='Password: ', stream=None):
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"""Prompt for a password, with echo turned off.
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prompt: Written on stream to ask for the input. Default: 'Password: '
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stream: A writable file object to display the prompt. Defaults to
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the tty. If no tty is available defaults to sys.stderr.
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EOFError: If our input tty or stdin was closed.
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GetPassWarning: When we were unable to turn echo off on the input.
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Always restores terminal settings before returning.
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# Always try reading and writing directly on the tty first.
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fd = os.open('/dev/tty', os.O_RDWR|os.O_NOCTTY)
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tty = os.fdopen(fd, 'w+', 1)
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except EnvironmentError, e:
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# If that fails, see if stdin can be controlled.
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fd = sys.stdin.fileno()
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passwd = fallback_getpass(prompt, stream)
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old = termios.tcgetattr(fd) # a copy to save
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new[3] &= ~termios.ECHO # 3 == 'lflags'
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termios.tcsetattr(fd, termios.TCSADRAIN, new)
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passwd = _raw_input(prompt, stream, input=input)
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termios.tcsetattr(fd, termios.TCSADRAIN, old)
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except termios.error, e:
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if passwd is not None:
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# _raw_input succeeded. The final tcsetattr failed. Reraise
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# instead of leaving the terminal in an unknown state.
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# We can't control the tty or stdin. Give up and use normal IO.
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# fallback_getpass() raises an appropriate warning.
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del input, tty # clean up unused file objects before blocking
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passwd = fallback_getpass(prompt, stream)
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def win_getpass(prompt='Password: ', stream=None):
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"""Prompt for password with echo off, using Windows getch()."""
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if sys.stdin is not sys.__stdin__:
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return fallback_getpass(prompt, stream)
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if c == '\r' or c == '\n':
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raise KeyboardInterrupt
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def fallback_getpass(prompt='Password: ', stream=None):
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warnings.warn("Can not control echo on the terminal.", GetPassWarning,
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print >>stream, "Warning: Password input may be echoed."
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return _raw_input(prompt, stream)
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def _raw_input(prompt="", stream=None, input=None):
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# A raw_input() replacement that doesn't save the string in the
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# GNU readline history.
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line = input.readline()
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"""Get the username from the environment or password database.
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First try various environment variables, then the password
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database. This works on Windows as long as USERNAME is set.
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for name in ('LOGNAME', 'USER', 'LNAME', 'USERNAME'):
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user = os.environ.get(name)
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# If this fails, the exception will "explain" why
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return pwd.getpwuid(os.getuid())[0]
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# Bind the name getpass to the appropriate function
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# it's possible there is an incompatible termios from the
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# McMillan Installer, make sure we have a UNIX-compatible termios
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termios.tcgetattr, termios.tcsetattr
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except (ImportError, AttributeError):
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from EasyDialogs import AskPassword
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getpass = fallback_getpass
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getpass = AskPassword
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getpass = win_getpass
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getpass = unix_getpass