Array methods for case conversion

libuavcan/include/uavcan/marshal/array.hpp

@@ -742,6 +742,38 @@ public:
         }
     }
 
+    /**
+     * Converts the string to upper/lower case in place, assuming that encoding is ASCII.
+     * These methods can only be used with string-like arrays; otherwise compilation will fail.
+     */
+    void convertToUpperCaseASCII()
+    {
+        StaticAssert<Base::IsStringLike>::check();
+
+        for (SizeType i = 0; i < size(); i++)
+        {
+            const int x = Base::at(i);
+            if ((x <= 'z') && (x >= 'a'))
+            {
+                Base::at(i) = static_cast<ValueType>(x + ('Z' - 'z'));
+            }
+        }
+    }
+
+    void convertToLowerCaseASCII()
+    {
+        StaticAssert<Base::IsStringLike>::check();
+
+        for (SizeType i = 0; i < size(); i++)
+        {
+            const int x = Base::at(i);
+            if ((x <= 'Z') && (x >= 'A'))
+            {
+                Base::at(i) = static_cast<ValueType>(x - ('Z' - 'z'));
+            }
+        }
+    }
+
     /**
      * Fills this array as a packed square matrix from a static array.
      * Please refer to the specification to learn more about matrix packing.

libuavcan/test/marshal/array.cpp

@@ -1278,3 +1278,21 @@ TEST(Array, FuzzyComparison)
     uavcan::YamlStreamer<ArrayDynamic64>::stream(std::cout, array_d64, 0);
     std::cout << std::endl;
 }
+
+TEST(Array, CaseConversion)
+{
+    Array<IntegerSpec<8, SignednessUnsigned, CastModeTruncate>, ArrayModeDynamic, 30> str;
+
+    str.convertToLowerCaseASCII();
+    str.convertToUpperCaseASCII();
+
+    ASSERT_STREQ("", str.c_str());
+
+    str = "Hello World!";
+
+    ASSERT_STREQ("Hello World!", str.c_str());
+    str.convertToLowerCaseASCII();
+    ASSERT_STREQ("hello world!", str.c_str());
+    str.convertToUpperCaseASCII();
+    ASSERT_STREQ("HELLO WORLD!", str.c_str());
+}