1 files changed, 123 insertions, 0 deletions
diff --git a/lib/yaml/encoding.rb b/lib/yaml/encoding.rb
new file mode 100644
index 0000000000..59491b53b7
--- /dev/null
+++ b/lib/yaml/encoding.rb
@@ -0,0 +1,123 @@
+#
+# Handle Unicode-to-Internal conversion
+#
+
+module YAML
+
+	#
+	# Encodings ( $-K to ICONV )
+	#
+	CHARSETS = {
+		'NONE' => 'LATIN1',
+		'ASCII' => 'US-ASCII',
+		'UTF-8' => 'UTF-8',
+		'EUC' => 'EUC-JP',
+		'SJIS' => 'SHIFT-JIS'
+	}
+
+	#
+	# YAML documents can be in UTF-8, UTF-16 or UTF-32
+	# So let's read and write in Unicode
+	#
+
+    @@unicode = false
+	begin
+		require 'iconv'
+		DEFAULTS[:Encoding] = :Utf8
+	rescue LoadError
+	end
+
+    def YAML.unicode; @@unicode; end
+    def YAML.unicode=( bool ); @@unicode = bool; end
+
+	#
+	# Unicode conversion
+	#
+    
+	def YAML.utf_to_internal( str, from_enc )
+		return unless str
+		to_enc = CHARSETS[$-K]
+		case from_enc
+			when :Utf32
+				Iconv.iconv( to_enc, 'UTF-32', str )[0]
+			when :Utf16
+				Iconv.iconv( to_enc, 'UTF-16', str )[0]
+			when :Utf8
+				Iconv.iconv( to_enc, 'UTF-8', str )[0]
+			when :None
+				str
+			else
+				raise YAML::Error, ERROR_UNSUPPORTED_ENCODING % from_enc.inspect
+		end
+	end
+
+	def YAML.internal_to_utf( str, to_enc )
+		return unless str
+		from_enc = CHARSETS[$-K]
+		case to_enc
+			when :Utf32
+				Iconv.iconv( 'UTF-32', from_enc, str )[0]
+			when :Utf16                        
+				Iconv.iconv( 'UTF-16', from_enc, str )[0]
+			when :Utf8                         
+				Iconv.iconv( 'UTF-8', from_enc, str )[0]
+			when :None
+				str
+			else
+				raise YAML::Error, ERROR_UNSUPPORTED_ENCODING % to_enc.inspect
+		end
+	end
+
+	def YAML.sniff_encoding( str )
+		unless YAML::unicode
+			:None
+		else
+			case str
+				when /^\x00\x00\xFE\xFF/	# UTF-32
+					:Utf32
+				when /^\xFE\xFF/	# UTF-32BE
+					:Utf16
+				else
+					:Utf8
+			end
+		end
+	end
+
+	def YAML.enc_separator( enc )
+		case enc
+			when :Utf32
+				"\000\000\000\n"
+			when :Utf16
+				"\000\n"
+			when :Utf8
+				"\n"
+			when :None
+				"\n"
+			else
+				raise YAML::Error, ERROR_UNSUPPORTED_ENCODING % enc.inspect
+		end
+	end
+
+	#
+	# Escape the string, condensing common escapes
+	#
+	def YAML.escape( value )
+		value.gsub( /\\/, "\\\\\\" ).gsub( /"/, "\\\"" ).gsub( /([\x00-\x1f])/ ) { |x| ESCAPES[ x.unpack("C")[0] ] }
+	end
+
+	#
+	# Unescape the condenses escapes
+	#
+	def YAML.unescape( value )
+		value.gsub( /\\(?:([nevbr\\fartz])|0?x([0-9a-fA-F]{2})|u([0-9a-fA-F]{4}))/ ) { |x| 
+			if $3
+				["#$3".hex ].pack('U*')
+			elsif $2
+				[$2].pack( "H2" ) 
+			else
+				UNESCAPES[$1] 
+			end
+		}
+	end
+
+end