VirtualMailManager/cli/__init__.py
changeset 571 a4aead244f75
parent 568 14abdd04ddf5
child 643 df1e3b67882a
child 675 d24f094d1cb5
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/VirtualMailManager/cli/__init__.py	Thu Jun 28 19:26:50 2012 +0000
@@ -0,0 +1,100 @@
+# -*- coding: UTF-8 -*-
+# Copyright (c) 2010 - 2012, Pascal Volk
+# See COPYING for distribution information.
+"""
+    VirtualMailManager.cli
+    ~~~~~~~~~~~~~~~~~~~~~~
+
+    VirtualMailManager's command line interface.
+"""
+
+import os
+from array import array
+from fcntl import ioctl
+from getpass import getpass
+from termios import TIOCGWINSZ
+
+from VirtualMailManager import ENCODING
+from VirtualMailManager.constants import VMM_TOO_MANY_FAILURES
+from VirtualMailManager.errors import VMMError
+
+
+__all__ = ('prog', 'get_winsize', 'read_pass', 'w_err', 'w_std')
+
+_ = lambda msg: msg
+_std_write = os.sys.stdout.write
+_err_write = os.sys.stderr.write
+prog = os.path.basename(os.sys.argv[0])
+
+
+def w_std(*args):
+    """Writes a line for each arg of *args*, encoded in the current
+    ENCODING, to stdout.
+    """
+    _std_write('\n'.join(a.encode(ENCODING, 'replace') for a in args) + '\n')
+
+
+def w_err(code, *args):
+    """Writes a line for each arg of *args*, encoded in the current
+    ENCODING, to stderr.
+    This function optionally interrupts the program execution if *code*
+    does not equal to 0. *code* will be used as the system exit status.
+    """
+    _err_write('\n'.join(a.encode(ENCODING, 'replace') for a in args) + '\n')
+    if code:
+        os.sys.exit(code)
+
+
+def get_winsize():
+    """Returns a tuple of integers ``(ws_row, ws_col)`` with the height and
+    width of the terminal."""
+    fd = None
+    for dev in (os.sys.stdout, os.sys.stderr, os.sys.stdin):
+        if hasattr(dev, 'fileno') and os.isatty(dev.fileno()):
+            fd = dev.fileno()
+            break
+    if fd is None:  # everything seems to be redirected
+        # fall back to environment or assume some common defaults
+        ws_row, ws_col = 24, 80
+        try:
+            ws_col = int(os.environ.get('COLUMNS', 80))
+            ws_row = int(os.environ.get('LINES', 24))
+        except ValueError:
+            pass
+        return ws_row, ws_col
+    #"struct winsize" with the ``unsigned short int``s ws_{row,col,{x,y}pixel}
+    ws = array('H', (0, 0, 0, 0))
+    ioctl(fd, TIOCGWINSZ, ws, True)
+    ws_row, ws_col = ws[:2]
+    return ws_row, ws_col
+
+
+def read_pass():
+    """Interactive 'password chat', returns the password in plain format.
+
+    Throws a VMMError after the third failure.
+    """
+    # TP: Please preserve the trailing space.
+    readp_msg0 = _(u'Enter new password: ').encode(ENCODING, 'replace')
+    # TP: Please preserve the trailing space.
+    readp_msg1 = _(u'Retype new password: ').encode(ENCODING, 'replace')
+    mismatched = True
+    failures = 0
+    while mismatched:
+        if failures > 2:
+            raise VMMError(_(u'Too many failures - try again later.'),
+                           VMM_TOO_MANY_FAILURES)
+        clear0 = getpass(prompt=readp_msg0)
+        clear1 = getpass(prompt=readp_msg1)
+        if clear0 != clear1:
+            failures += 1
+            w_err(0, _(u'Sorry, passwords do not match.'))
+            continue
+        if not clear0:
+            failures += 1
+            w_err(0, _(u'Sorry, empty passwords are not permitted.'))
+            continue
+        mismatched = False
+    return clear0
+
+del _