Query methods for VINTF native instances

isDeclared(name), getDeclaredInstances(interface),
updatableViaApex(name), and getUpdatableNames(apexName) are extended to
support native instances when
- "name" is formatted as e.g. "mapper/minigbm",
- "interface" is formatted as e.g. "mapper"

Bug: 316051788
Test: atest servicemanager_test
Test: atest --host servicemanager_unittest
Change-Id: I0520888dbf5d30c66b97058f45cd6828731ca8bc
diff --git a/cmds/servicemanager/NameUtil.h b/cmds/servicemanager/NameUtil.h
new file mode 100644
index 0000000..b080939
--- /dev/null
+++ b/cmds/servicemanager/NameUtil.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <string>
+#include <string_view>
+
+#include <android-base/strings.h>
+
+namespace android {
+
+#ifndef VENDORSERVICEMANAGER
+
+struct NativeName {
+    std::string package;
+    std::string instance;
+
+    // Parse {package}/{instance}
+    static bool fill(std::string_view name, NativeName* nname) {
+        size_t slash = name.find('/');
+        if (slash == std::string_view::npos) {
+            return false;
+        }
+        // no extra slashes
+        if (name.find('/', slash + 1) != std::string_view::npos) {
+            return false;
+        }
+        // every part should be non-empty
+        if (slash == 0 || slash + 1 == name.size()) {
+            return false;
+        }
+        // no dots in package
+        if (name.rfind('.', slash) != std::string_view::npos) {
+            return false;
+        }
+        nname->package = name.substr(0, slash);
+        nname->instance = name.substr(slash + 1);
+        return true;
+    }
+};
+
+#endif
+
+} // namespace android