def find_data_files(data):
    """Find distribution data files, using an API similar to
    package_data setup argument.
    """

    data_files = {}

    for target, globs in data.iteritems():
        files = set()
        for pattern in globs:
            # Each pattern has to be converted to a platform-specific path
            for fn in glob(convert_path(pattern)):
                # Files that match more than one pattern are only added once
                # XXX check me
                if fn in files:
                    continue
                else:
                    files.add(fn)

                if not target:
                    # Emulate package_data behaviour
                    target_path = os.path.dirname(fn)
                    data_files.setdefault(target_path, []).append(fn)
                else:
                    #  Emulate data_files behaviour
                    data_files.setdefault(target, []).append(fn)

    return [(target, path) for target, path in data_files.iteritems()]