Ruby - File 의 sha1sum, md5sum 구하기

아래의 코드는 Linux 명령어 중에서 sha1sum, md5sum 명령어와 같은 기능을 하는 코드입니다.

# Simple Hash Code Calculator

# Returns SHA1 and MD5 hash sum for any given file

require 'digest/md5'

require 'digest/sha1'

# buffer size 4 kbytes

BUFFER_SIZE = 4096

class Hasher

# method = "sha1" or "md5"

# filepath = Full filepath

def initialize(method, filepath)

if (method.upcase == "-SHA1")

@hashfunc = Digest::SHA1.new

@hashname = "SHA1"

else

@hashfunc = Digest::MD5.new

@hashname = "MD5"

end

@fullfilename = filepath

end

def hashname

@hashname

end

# Compute hash code

def hashsum

open(@fullfilename, "r") do |io|

puts "Reading "+@fullfilename

counter = 0

while (!io.eof)

readBuf = io.readpartial(BUFFER_SIZE)

putc '.' if ((counter+=1) % 3 == 0)

@hashfunc.update(readBuf)

end

end

return @hashfunc.hexdigest

end

end

def usage

puts "Usage: hash.rb [-sha1|-md5] filename"

end

def print_result(filename, method, sum)

puts "\n" + filename + " ==> "+ method + ": " + sum

end

#Program starts

if(ARGV.length < 1)

usage

elsif (ARGV.length == 2)

hashcomp = Hasher.new(ARGV[0], ARGV[1])

print_result(ARGV[1], hashcomp.hashname, hashcomp.hashsum)

elsif (ARGV.length == 1)

hashcomp = Hasher.new("-sha1", ARGV[0])

print_result(ARGV[0], hashcomp.hashname, hashcomp.hashsum)

end