#! /usr/bin/env python

"""Python utility to print MD5 checksums of argument files.

"""

bufsize = 8096

fnfilter = None

rmode = 'rb'

usage = """

usage: sum5 [-b] [-t] [-l] [-s bufsize] [file ...]

-b        : read files in binary mode (default)

-t        : read files in text mode (you almost certainly don't want this!)

-l        : print last pathname component only

-s bufsize: read buffer size (default %d)

file ...  : files to sum; '-' or no files means stdin

""" % bufsize

import sys

import os

import getopt

import md5

def sum(*files):

    sts = 0

    if files and isinstance(files[-1], file):

        out, files = files[-1], files[:-1]

    else:

        out = sys.stdout

    if len(files) == 1 and not isinstance(files[0], str):

        files = files[0]

    for f in files:

        if isinstance(f, str):

            if f == '-':

                sts = printsumfp(sys.stdin, '<stdin>', out) or sts

            else:

                sts = printsum(f, out) or sts

        else:

            sts = sum(f, out) or sts

    return sts

def printsum(filename, out=sys.stdout):

    try:

        fp = open(filename, rmode)

    except IOError, msg:

        sys.stderr.write('%s: Can\'t open: %s\n' % (filename, msg))

        return 1

    if fnfilter:

        filename = fnfilter(filename)

    sts = printsumfp(fp, filename, out)

    fp.close()

    return sts

def printsumfp(fp, filename, out=sys.stdout):

    m = md5.new()

    try:

        while 1:

            data = fp.read(bufsize)

            if not data:

                break

            m.update(data)

    except IOError, msg:

        sys.stderr.write('%s: I/O error: %s\n' % (filename, msg))

        return 1

    out.write('%s %s\n' % (m.hexdigest(), filename))

    return 0

def main(args = sys.argv[1:], out=sys.stdout):

    global fnfilter, rmode, bufsize

    try:

        opts, args = getopt.getopt(args, 'blts:')

    except getopt.error, msg:

        sys.stderr.write('%s: %s\n%s' % (sys.argv[0], msg, usage))

        return 2

    for o, a in opts:

        if o == '-l':

            fnfilter = os.path.basename

        elif o == '-b':

            rmode = 'rb'

        elif o == '-t':

            rmode = 'r'

        elif o == '-s':

            bufsize = int(a)

    if not args:

        args = ['-']

    return sum(args, out)

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

    sys.exit(main(sys.argv[1:], sys.stdout))