Added X86::RelativeOffset (closes #102).

lib/ronin/asm/x86/relative_offset.rb

@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+#
+# ronin-asm - A Ruby DSL for crafting Assembly programs and shellcode.
+#
+# Copyright (c) 2007-2025 Hal Brodigan (postmodern.mod3 at gmail.com)
+#
+# ronin-asm is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# ronin-asm is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with ronin-asm.  If not, see <https://www.gnu.org/licenses/>.
+#
+
+require_relative '../operand'
+
+module Ronin
+  module ASM
+    module X86
+      #
+      # Represents a relative offset (`rel8` or `rel32`).
+      #
+      # @since 1.0.0
+      #
+      class RelativeOffset < Operand
+
+        # The relative offset value.
+        #
+        # @return [Integer]
+        attr_reader :value
+
+        # The size of the relative offset operand.
+        #
+        # @return [1, 4]
+        attr_reader :width
+
+        # The operand type.
+        #
+        # @return [:rel8, :rel32]
+        attr_reader :type
+
+        #
+        # Initializes the relative offset.
+        #
+        # @param [Integer] value
+        #   The relative offset value.
+        #
+        def initialize(value)
+          @value = value
+          @width = if value.bit_length <= 8 then 1
+                   else                          4
+                   end
+          @type  = :"rel#{@width * 8}"
+        end
+
+      end
+    end
+  end
+end

spec/x86/relative_offset_spec.rb

@@ -0,0 +1,38 @@
+require 'spec_helper'
+require 'ronin/asm/x86/relative_offset'
+
+describe Ronin::ASM::X86::RelativeOffset do
+  let(:value) { 0x1000 }
+
+  subject { described_class.new(value) }
+
+  describe "#initialize" do
+    it "must set #value" do
+      expect(subject.value).to eq(value)
+    end
+
+    context "when the value has a bit length less or equal to 8 bits" do
+      let(:value) { 0x10 }
+
+      it "must set #width to 1" do
+        expect(subject.width).to eq(1)
+      end
+
+      it "must set #type to :rel8" do
+        expect(subject.type).to eq(:rel8)
+      end
+    end
+
+    context "when the value has a bit length less or equal to 32bits" do
+      let(:value) { 0x11223344 }
+
+      it "must set #width to 4" do
+        expect(subject.width).to eq(4)
+      end
+
+      it "must set #type to :rel32" do
+        expect(subject.type).to eq(:rel32)
+      end
+    end
+  end
+end