Use c_char instead of u8 for char translation

Author: lucic71

cpp2rust/converter/converter.cpp

@@ -123,8 +123,13 @@ bool Converter::VisitBuiltinType(clang::BuiltinType *type) {
     StrCat("f64");
     break;
   case clang::BuiltinType::Char_S:
-  case clang::BuiltinType::UChar:
+  case clang::BuiltinType::Char_U:
+    StrCat("::core::ffi::c_char");
+    break;
   case clang::BuiltinType::SChar:
+    StrCat("i8");
+    break;
+  case clang::BuiltinType::UChar:
     StrCat("u8");
     break;
   case clang::BuiltinType::UShort:

cpp2rust/converter/mapper.cpp

@@ -524,7 +524,7 @@ void addBuiltinTypes(Model model) {
   }
 
   // Char
-  add_builtin_rule(ctx_->CharTy, "u8");
+  add_builtin_rule(ctx_->CharTy, "::core::ffi::c_char");
   add_builtin_rule(ctx_->SignedCharTy, "i8");
   add_builtin_rule(ctx_->UnsignedCharTy, "u8");