vaguerent/lib/vagrant/util/numeric.rb

93 lines
3.0 KiB
Ruby

# Copyright (c) HashiCorp, Inc.
# SPDX-License-Identifier: BUSL-1.1
require "log4r"
module Vagrant
module Util
class Numeric
# Authors Note: This conversion has been borrowed from the ActiveSupport Numeric class
# Conversion helper constants
KILOBYTE = 1024
MEGABYTE = KILOBYTE * 1024
GIGABYTE = MEGABYTE * 1024
TERABYTE = GIGABYTE * 1024
PETABYTE = TERABYTE * 1024
EXABYTE = PETABYTE * 1024
BYTES_CONVERSION_MAP = {KB: KILOBYTE, MB: MEGABYTE, GB: GIGABYTE, TB: TERABYTE,
PB: PETABYTE, EB: EXABYTE}
# Regex borrowed from the vagrant-disksize config class
SHORTHAND_MATCH_REGEX = /^(?<number>[0-9]+)\s?(?<unit>KB|MB|GB|TB)?$/
class << self
LOGGER = Log4r::Logger.new("vagrant::util::numeric")
# A helper that converts a shortcut string to its bytes representation.
# The expected format of `str` is essentially: "<Number>XX"
# Where `XX` is shorthand for KB, MB, GB, TB, PB, or EB. For example, 50 megabytes:
#
# str = "50MB"
#
# @param [String] - str
# @return [Integer,nil] - bytes - returns nil if method fails to convert to bytes
def string_to_bytes(str)
bytes = nil
str = str.to_s.strip
matches = SHORTHAND_MATCH_REGEX.match(str)
if matches
number = matches[:number].to_i
unit = matches[:unit].to_sym
if BYTES_CONVERSION_MAP.key?(unit)
bytes = number * BYTES_CONVERSION_MAP[unit]
else
LOGGER.error("An invalid unit or format was given, string_to_bytes cannot convert #{str}")
end
end
bytes
end
# Convert bytes to a user friendly string representation
#
# @param [Numeric] bytes Number of bytes to represent
# @return [String] user friendly output
def bytes_to_string(bytes)
# We want to locate the size that will return the
# smallest whole value number
BYTES_CONVERSION_MAP.sort { |a, b|
b.last <=> a.last
}.each do |suffix, size|
val = bytes.to_f / size
next if val < 1
val = sprintf("%.2f", val)
val.slice!(-1, 1) while val.end_with?("0")
val.slice!(-1, 1) if val.end_with?(".")
return "#{val}#{suffix}"
end
"#{bytes} byte#{"s" if bytes > 1}"
end
# Rounds actual value to two decimal places
#
# @param [Integer] bytes
# @return [Integer] megabytes - bytes representation in megabytes
def bytes_to_megabytes(bytes)
(bytes / MEGABYTE.to_f).round(2)
end
# @private
# Reset the cached values for platform. This is not considered a public
# API and should only be used for testing.
def reset!
instance_variables.each(&method(:remove_instance_variable))
end
end
end
end
end