1require 'digest.so' 2 3module Digest 4 def self.const_missing(name) # :nodoc: 5 case name 6 when :SHA256, :SHA384, :SHA512 7 lib = 'digest/sha2.so' 8 else 9 lib = File.join('digest', name.to_s.downcase) 10 end 11 12 begin 13 require lib 14 rescue LoadError 15 raise LoadError, "library not found for class Digest::#{name} -- #{lib}", caller(1) 16 end 17 unless Digest.const_defined?(name) 18 raise NameError, "uninitialized constant Digest::#{name}", caller(1) 19 end 20 Digest.const_get(name) 21 end 22 23 class ::Digest::Class 24 # creates a digest object and reads a given file, _name_. 25 # 26 # p Digest::SHA256.file("X11R6.8.2-src.tar.bz2").hexdigest 27 # # => "f02e3c85572dc9ad7cb77c2a638e3be24cc1b5bea9fdbb0b0299c9668475c534" 28 def self.file(name) 29 new.file(name) 30 end 31 32 # Returns the base64 encoded hash value of a given _string_. The 33 # return value is properly padded with '=' and contains no line 34 # feeds. 35 def self.base64digest(str, *args) 36 [digest(str, *args)].pack('m0') 37 end 38 end 39 40 module Instance 41 # updates the digest with the contents of a given file _name_ and 42 # returns self. 43 def file(name) 44 File.open(name, "rb") {|f| 45 buf = "" 46 while f.read(16384, buf) 47 update buf 48 end 49 } 50 self 51 end 52 53 # If none is given, returns the resulting hash value of the digest 54 # in a base64 encoded form, keeping the digest's state. 55 # 56 # If a +string+ is given, returns the hash value for the given 57 # +string+ in a base64 encoded form, resetting the digest to the 58 # initial state before and after the process. 59 # 60 # In either case, the return value is properly padded with '=' and 61 # contains no line feeds. 62 def base64digest(str = nil) 63 [str ? digest(str) : digest].pack('m0') 64 end 65 66 # Returns the resulting hash value and resets the digest to the 67 # initial state. 68 def base64digest! 69 [digest!].pack('m0') 70 end 71 end 72end 73 74# call-seq: 75# Digest(name) -> digest_subclass 76# 77# Returns a Digest subclass by +name+. 78# 79# require 'digest' 80# 81# Digest("MD5") 82# # => Digest::MD5 83# 84# Digest("Foo") 85# # => LoadError: library not found for class Digest::Foo -- digest/foo 86def Digest(name) 87 Digest.const_get(name) 88end 89