rename data_object to string_node and move the padding there

lib/asm/arm/arm_assembler.rb

@@ -6,7 +6,7 @@ require 'asm/arm/generator_label'
 require 'asm/nodes'
 require 'stream_reader'
 require 'stringio'
-require "asm/data_object"
+require "asm/string_node"
 
 module Asm
   module Arm

lib/asm/arm/normal_builder.rb

@@ -46,7 +46,7 @@ module Asm
       def build_operand(arg , position = 0) 
         #position only needed for calculating relative addresses to data objects
         #there is a design stink here which makes my head ache. But shanti shanti
-        if arg.is_a?(Asm::DataObject)
+        if arg.is_a?(Asm::StringNode)
           # do pc relative addressing with the difference to the instuction
           # 8 is for the funny pipeline adjustment (ie oc pointing to fetch and not execute)
           arg = Asm::NumLiteralNode.new( arg.position - position - 8 )

lib/asm/assembler.rb

@@ -16,7 +16,7 @@ module Asm
     def add_string str
       value = @string_table[str]
       return value if value
-      data = Asm::DataObject.new(str)
+      data = Asm::StringNode.new(str)
       @string_table[str] = data
     end
     
@@ -27,8 +27,6 @@ module Asm
     def add_value(val)
       val.at(@position)
       length = val.length
-      #rounding up to the next 4
-      length = (((length - 1 ) / 4 ) + 1 ) * 4 
       @position += length
       @values << val
     end

lib/asm/data_object.rb

@@ -1,21 +0,0 @@
-module Asm
-  class DataObject
-    def initialize(data)
-      @data = data
-    end
-    
-    def position
-      throw "Not set" unless @address
-      @address 
-    end
-    def at address
-      @address = address
-    end
-    def length
-      @data.length
-    end
-    def assemble(io, as)
-      io << @data
-    end
-  end
-end

lib/asm/string_node.rb

@@ -0,0 +1,26 @@
+module Asm
+  class StringNode
+    def initialize(str)
+      #align
+      length = str.length 
+      # rounding up to the next 4 (always adding one for zero pad)
+      pad =  ((length / 4 ) + 1 ) * 4 - length
+      raise "#{pad} #{self}" unless pad >= 1
+      @string = str + "\x00" * pad 
+    end
+    
+    def position
+      throw "Not set" unless @address
+      @address 
+    end
+    def at address
+      @address = address
+    end
+    def length
+      @string.length
+    end
+    def assemble(io, as)
+      io << @string
+    end
+  end
+end