#!/usr/bin/env python

"""

Synopsis: %(prog)s [-h|-g|-b|-r|-a] dbfile [ picklefile ]

Convert the database file given on the command line to a pickle

representation.  The optional flags indicate the type of the database:

    -a - open using anydbm

    -b - open as bsddb btree file

    -d - open as dbm file

    -g - open as gdbm file

    -h - open as bsddb hash file

    -r - open as bsddb recno file

The default is hash.  If a pickle file is named it is opened for write

access (deleting any existing data).  If no pickle file is named, the pickle

output is written to standard output.

"""

import getopt

try:

    import bsddb

except ImportError:

    bsddb = None

try:

    import dbm

except ImportError:

    dbm = None

try:

    import gdbm

except ImportError:

    gdbm = None

try:

    import anydbm

except ImportError:

    anydbm = None

import sys

try:

    import cPickle as pickle

except ImportError:

    import pickle

prog = sys.argv[0]

def usage():

    sys.stderr.write(__doc__ % globals())

def main(args):

    try:

        opts, args = getopt.getopt(args, "hbrdag",

                                   ["hash", "btree", "recno", "dbm",

                                    "gdbm", "anydbm"])

    except getopt.error:

        usage()

        return 1

    if len(args) == 0 or len(args) > 2:

        usage()

        return 1

    elif len(args) == 1:

        dbfile = args[0]

        pfile = sys.stdout

    else:

        dbfile = args[0]

        try:

            pfile = open(args[1], 'wb')

        except IOError:

            sys.stderr.write("Unable to open %s\n" % args[1])

            return 1

    dbopen = None

    for opt, arg in opts:

        if opt in ("-h", "--hash"):

            try:

                dbopen = bsddb.hashopen

            except AttributeError:

                sys.stderr.write("bsddb module unavailable.\n")

                return 1

        elif opt in ("-b", "--btree"):

            try:

                dbopen = bsddb.btopen

            except AttributeError:

                sys.stderr.write("bsddb module unavailable.\n")

                return 1

        elif opt in ("-r", "--recno"):

            try:

                dbopen = bsddb.rnopen

            except AttributeError:

                sys.stderr.write("bsddb module unavailable.\n")

                return 1

        elif opt in ("-a", "--anydbm"):

            try:

                dbopen = anydbm.open

            except AttributeError:

                sys.stderr.write("anydbm module unavailable.\n")

                return 1

        elif opt in ("-g", "--gdbm"):

            try:

                dbopen = gdbm.open

            except AttributeError:

                sys.stderr.write("gdbm module unavailable.\n")

                return 1

        elif opt in ("-d", "--dbm"):

            try:

                dbopen = dbm.open

            except AttributeError:

                sys.stderr.write("dbm module unavailable.\n")

                return 1

    if dbopen is None:

        if bsddb is None:

            sys.stderr.write("bsddb module unavailable - ")

            sys.stderr.write("must specify dbtype.\n")

            return 1

        else:

            dbopen = bsddb.hashopen

    try:

        db = dbopen(dbfile, 'r')

    except bsddb.error:

        sys.stderr.write("Unable to open %s.  " % dbfile)

        sys.stderr.write("Check for format or version mismatch.\n")

        return 1

    for k in db.keys():

        pickle.dump((k, db[k]), pfile, 1==1)

    db.close()

    pfile.close()

    return 0

if __name__ == "__main__":

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