AAPT2: Implement XmlActionExecutor to verify manifest

Defines a set of actions to perform on XML elements defined by their
hierarchy, eg: manifest -> application -> activity.

This can be used to easily add rules to check more tags in AndroidManifest.xml

Change-Id: I76c6916a98b6403075a7e56e16230979dc6cbee1

1 files changed, 112 insertions, 0 deletions

diff --git a/tools/aapt2/xml/XmlActionExecutor.cpp b/tools/aapt2/xml/XmlActionExecutor.cpp
new file mode 100644
index 000000000000..0ef67eaf3dc5
--- /dev/null
+++ b/tools/aapt2/xml/XmlActionExecutor.cpp
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include "xml/XmlActionExecutor.h"
+
+namespace aapt {
+namespace xml {
+
+static bool wrapperOne(XmlNodeAction::ActionFunc& f, Element* el, SourcePathDiagnostics*) {
+    return f(el);
+}
+
+static bool wrapperTwo(XmlNodeAction::ActionFuncWithDiag& f, Element* el,
+                       SourcePathDiagnostics* diag) {
+    return f(el, diag);
+}
+
+void XmlNodeAction::action(XmlNodeAction::ActionFunc f) {
+    mActions.emplace_back(std::bind(wrapperOne, std::move(f),
+                                    std::placeholders::_1,
+                                    std::placeholders::_2));
+}
+
+void XmlNodeAction::action(XmlNodeAction::ActionFuncWithDiag f) {
+    mActions.emplace_back(std::bind(wrapperTwo, std::move(f),
+                                    std::placeholders::_1,
+                                    std::placeholders::_2));
+}
+
+static void printElementToDiagMessage(const Element* el, DiagMessage* msg) {
+    *msg << "<";
+    if (!el->namespaceUri.empty()) {
+        *msg << el->namespaceUri << ":";
+    }
+    *msg << el->name << ">";
+}
+
+bool XmlNodeAction::execute(XmlActionExecutorPolicy policy, SourcePathDiagnostics* diag,
+                            Element* el) const {
+    bool error = false;
+    for (const ActionFuncWithDiag& action : mActions) {
+        error |= !action(el, diag);
+    }
+
+    for (Element* childEl : el->getChildElements()) {
+        if (childEl->namespaceUri.empty()) {
+            std::map<std::u16string, XmlNodeAction>::const_iterator iter =
+                    mMap.find(childEl->name);
+            if (iter != mMap.end()) {
+                error |= !iter->second.execute(policy, diag, childEl);
+                continue;
+            }
+        }
+
+        if (policy == XmlActionExecutorPolicy::Whitelist) {
+            DiagMessage errorMsg(childEl->lineNumber);
+            errorMsg << "unknown element ";
+            printElementToDiagMessage(childEl, &errorMsg);
+            errorMsg << " found";
+            diag->error(errorMsg);
+            error = true;
+        }
+    }
+    return !error;
+}
+
+bool XmlActionExecutor::execute(XmlActionExecutorPolicy policy, IDiagnostics* diag,
+                                XmlResource* doc) const {
+    SourcePathDiagnostics sourceDiag(doc->file.source, diag);
+
+    Element* el = findRootElement(doc);
+    if (!el) {
+        if (policy == XmlActionExecutorPolicy::Whitelist) {
+            sourceDiag.error(DiagMessage() << "no root XML tag found");
+            return false;
+        }
+        return true;
+    }
+
+    if (el->namespaceUri.empty()) {
+        std::map<std::u16string, XmlNodeAction>::const_iterator iter = mMap.find(el->name);
+        if (iter != mMap.end()) {
+            return iter->second.execute(policy, &sourceDiag, el);
+        }
+    }
+
+    if (policy == XmlActionExecutorPolicy::Whitelist) {
+        DiagMessage errorMsg(el->lineNumber);
+        errorMsg << "unknown element ";
+        printElementToDiagMessage(el, &errorMsg);
+        errorMsg << " found";
+        sourceDiag.error(errorMsg);
+        return false;
+    }
+    return true;
+}
+
+} // namespace xml
+} // namespace aapt