add check to prevent sizeof(void) generation

lib/cmock_generator_plugin_return_thru_ptr.rb

@@ -2,9 +2,10 @@ class CMockGeneratorPluginReturnThruPtr
   attr_reader :priority
   attr_accessor :utils
 
-  def initialize(_config, utils)
+  def initialize(config, utils)
     @utils        = utils
     @priority     = 9
+    @config       = config
   end
 
   def instance_typedefs(function)
@@ -19,6 +20,15 @@ class CMockGeneratorPluginReturnThruPtr
     lines
   end
 
+  def void_pointer?(type)
+    # returns true if the provided type is a void, or is supposed to be treated as void
+    if type.casecmp?('void')
+      true
+    else
+      @config.respond_to?(:treat_as_void) ? @config.treat_as_void.include?(type) : false
+    end
+  end
+
   def mock_function_declarations(function)
     lines = ''
     function[:args].each do |arg|
@@ -27,7 +37,8 @@ class CMockGeneratorPluginReturnThruPtr
       lines << "#define #{function[:name]}_ReturnThruPtr_#{arg[:name]}(#{arg[:name]})"
       # If the pointer type actually contains an asterisk, we can do sizeof the type (super safe), otherwise
       # we need to do a sizeof the dereferenced pointer (which could be a problem if give the wrong size
-      lines << if arg[:type][-1] == '*'
+      # however if its a void pointer we are given then we have to use the provided parameter name because sizeof(void) is UB.
+      lines << if (arg[:type][-1] == '*') && (void_pointer?(arg[:type][0..-2]) == false)
                  " #{function[:name]}_CMockReturnMemThruPtr_#{arg[:name]}(__LINE__, #{arg[:name]}, sizeof(#{arg[:type][0..-2]}))\n"
                else
                  " #{function[:name]}_CMockReturnMemThruPtr_#{arg[:name]}(__LINE__, #{arg[:name]}, sizeof(*#{arg[:name]}))\n"

test/unit/cmock_generator_plugin_return_thru_ptr_test.rb

@@ -39,6 +39,18 @@ describe CMockGeneratorPluginReturnThruPtr, "Verify CMockGeneratorPluginReturnTh
                      :return => test_return[:void],
                      :contains_ptr? => true }
 
+    @void_ptr_func = {:name => "Spruce",
+                      :args => [{ :type => "void*",
+                                :name => "pork",
+                                :ptr? => true,
+                              },
+                              { :type => "MY_FANCY_VOID*",
+                                :name => "salad",
+                                :ptr? => true,
+                              }],
+                      :return => test_return[:void],
+                      :contains_ptr? => true }
+
     #no strict ordering
     @cmock_generator_plugin_return_thru_ptr = CMockGeneratorPluginReturnThruPtr.new(@config, @utils)
   end
@@ -56,6 +68,13 @@ describe CMockGeneratorPluginReturnThruPtr, "Verify CMockGeneratorPluginReturnTh
     @utils.expect :ptr_or_str?, true, ['int*']
   end
 
+  def void_ptr_func_expect
+    @utils.expect :ptr_or_str?, true, ['void*']
+    @utils.expect :ptr_or_str?, true, ['MY_FANCY_VOID*']
+
+    @config.expect :treat_as_void, ['MY_FANCY_VOID']
+  end
+
   it "have set up internal priority correctly on init" do
     assert_equal(9, @cmock_generator_plugin_return_thru_ptr.priority)
   end
@@ -100,6 +119,29 @@ describe CMockGeneratorPluginReturnThruPtr, "Verify CMockGeneratorPluginReturnTh
     assert_equal(expected, returned)
   end
 
+  it "add a mock function declaration with sizeof(<name>) for void pointer arguments" do
+    void_ptr_func_expect();
+
+    expected =
+    "#define Spruce_ReturnThruPtr_pork(pork)" +
+    " Spruce_CMockReturnMemThruPtr_pork(__LINE__, pork, sizeof(*pork))\n" +
+    "#define Spruce_ReturnArrayThruPtr_pork(pork, cmock_len)" +
+    " Spruce_CMockReturnMemThruPtr_pork(__LINE__, pork, cmock_len * sizeof(*pork))\n" +
+    "#define Spruce_ReturnMemThruPtr_pork(pork, cmock_size)" +
+    " Spruce_CMockReturnMemThruPtr_pork(__LINE__, pork, cmock_size)\n" +
+    "void Spruce_CMockReturnMemThruPtr_pork(UNITY_LINE_TYPE cmock_line, void* pork, size_t cmock_size);\n" + 
+    "#define Spruce_ReturnThruPtr_salad(salad)" +
+    " Spruce_CMockReturnMemThruPtr_salad(__LINE__, salad, sizeof(*salad))\n" +
+    "#define Spruce_ReturnArrayThruPtr_salad(salad, cmock_len)" +
+    " Spruce_CMockReturnMemThruPtr_salad(__LINE__, salad, cmock_len * sizeof(*salad))\n" +
+    "#define Spruce_ReturnMemThruPtr_salad(salad, cmock_size)" +
+    " Spruce_CMockReturnMemThruPtr_salad(__LINE__, salad, cmock_size)\n" +
+    "void Spruce_CMockReturnMemThruPtr_salad(UNITY_LINE_TYPE cmock_line, MY_FANCY_VOID* salad, size_t cmock_size);\n"
+
+    returned = @cmock_generator_plugin_return_thru_ptr.mock_function_declarations(@void_ptr_func)
+    assert_equal(expected, returned)
+  end
+
   it "add mock interfaces only for non-const pointer arguments" do
     complex_func_expect();