#! /usr/bin/env python
# Copyright (c) 2006 The Regents of The University of Michigan
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met: redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer;
# redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS 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 THE COPYRIGHT
# OWNER OR CONTRIBUTORS 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.
#
# Authors: Nathan Binkert

import re
import os
import sys
from getopt import getopt, GetoptError

tabs = re.compile(r'^[ \t]+')
def fixwhite(filename, tabsize):
    try:
        f = file(filename, 'r+')
    except OSError, msg:
        print 'could not open file %s: %s' % (filename, msg)
        return

    lines = list(f)

    f.seek(0)
    f.truncate()
    
    for line in lines:
        if tabs.search(line):
            newline = ''
            for i,c in enumerate(line):
                if c == ' ':
                    newline += ' '
                elif c == '\t':
                    newline += ' ' * (tabsize - len(newline) % tabsize)
                else:
                    newline += line[i:]
                    break

            line = newline

        print >>f, line.rstrip()

if __name__ == '__main__':
    progname = sys.argv[0]

    def usage(code=None):
        print >>sys.stderr, '''%s [-t <tabsize>] <filenames>''' % progname
        if code is not None:
            sys.exit(code)

    try:
        opts, args = getopt(sys.argv[1:], '-t:')
    except GetoptError:
        usage(2)

    tabsize = 8
    for opt,arg in opts:
        if opt == '-t':
            tabsize = int(arg)

    for filename in args:
        fixwhite(filename, tabsize)