util.py

# Copyright 2017 The Regents of the University of Michigan
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the "Software"), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
# of the Software, and to permit persons to whom the Software is furnished to do
# so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# SOFTWARE.
import os
import psutil


def fmt_size(size, units=None):
    "Returns a human readable string reprentation of bytes."
    if units is None:
        units = [' bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB']
    return str(size) + units.pop(0) if size < 1024 else fmt_size(size >> 10, units[1:])


def get_partition(path):
    path = os.path.realpath(path)
    candidates = dict()
    for partition in psutil.disk_partitions(all=True):
        mp = os.path.realpath(partition.mountpoint)
        if path.startswith(mp):
            candidates[mp] = partition
    if candidates:
        return candidates[list(sorted(candidates, key=len))[-1]]
    else:
        raise LookupError(path)