diff options
Diffstat (limited to 'ext/digest/lib/digest.rb')
-rw-r--r-- | ext/digest/lib/digest.rb | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/ext/digest/lib/digest.rb b/ext/digest/lib/digest.rb new file mode 100644 index 0000000..4a98af2 --- /dev/null +++ b/ext/digest/lib/digest.rb @@ -0,0 +1,88 @@ +require 'digest.so' + +module Digest + def self.const_missing(name) # :nodoc: + case name + when :SHA256, :SHA384, :SHA512 + lib = 'digest/sha2.so' + else + lib = File.join('digest', name.to_s.downcase) + end + + begin + require lib + rescue LoadError + raise LoadError, "library not found for class Digest::#{name} -- #{lib}", caller(1) + end + unless Digest.const_defined?(name) + raise NameError, "uninitialized constant Digest::#{name}", caller(1) + end + Digest.const_get(name) + end + + class ::Digest::Class + # creates a digest object and reads a given file, _name_. + # + # p Digest::SHA256.file("X11R6.8.2-src.tar.bz2").hexdigest + # # => "f02e3c85572dc9ad7cb77c2a638e3be24cc1b5bea9fdbb0b0299c9668475c534" + def self.file(name) + new.file(name) + end + + # Returns the base64 encoded hash value of a given _string_. The + # return value is properly padded with '=' and contains no line + # feeds. + def self.base64digest(str, *args) + [digest(str, *args)].pack('m0') + end + end + + module Instance + # updates the digest with the contents of a given file _name_ and + # returns self. + def file(name) + File.open(name, "rb") {|f| + buf = "" + while f.read(16384, buf) + update buf + end + } + self + end + + # If none is given, returns the resulting hash value of the digest + # in a base64 encoded form, keeping the digest's state. + # + # If a +string+ is given, returns the hash value for the given + # +string+ in a base64 encoded form, resetting the digest to the + # initial state before and after the process. + # + # In either case, the return value is properly padded with '=' and + # contains no line feeds. + def base64digest(str = nil) + [str ? digest(str) : digest].pack('m0') + end + + # Returns the resulting hash value and resets the digest to the + # initial state. + def base64digest! + [digest!].pack('m0') + end + end +end + +# call-seq: +# Digest(name) -> digest_subclass +# +# Returns a Digest subclass by +name+. +# +# require 'digest' +# +# Digest("MD5") +# # => Digest::MD5 +# +# Digest("Foo") +# # => LoadError: library not found for class Digest::Foo -- digest/foo +def Digest(name) + Digest.const_get(name) +end |