AAPT2: Add diff command

Adds the diff command and various small fixes to issues
discovered when diffing old AAPT built APKs with new AAPT2
built APKS.

Bug:22775504
Change-Id: I682a7fe1cf4b3efa7cbd5d18b333cf2d1046fe1b

1 files changed, 411 insertions, 0 deletions

diff --git a/tools/aapt2/diff/Diff.cpp b/tools/aapt2/diff/Diff.cpp
new file mode 100644
index 000000000000..20b7b59642ca
--- /dev/null
+++ b/tools/aapt2/diff/Diff.cpp
@@ -0,0 +1,411 @@
+/*
+ * 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 "Flags.h"
+#include "ResourceTable.h"
+#include "io/ZipArchive.h"
+#include "process/IResourceTableConsumer.h"
+#include "process/SymbolTable.h"
+#include "unflatten/BinaryResourceParser.h"
+
+#include <android-base/macros.h>
+
+namespace aapt {
+
+class DiffContext : public IAaptContext {
+public:
+    const std::u16string& getCompilationPackage() override {
+        return mEmpty;
+    }
+
+    uint8_t getPackageId() override {
+        return 0x0;
+    }
+
+    IDiagnostics* getDiagnostics() override {
+        return &mDiagnostics;
+    }
+
+    NameMangler* getNameMangler() override {
+        return &mNameMangler;
+    }
+
+    SymbolTable* getExternalSymbols() override {
+        return &mSymbolTable;
+    }
+
+    bool verbose() override {
+        return false;
+    }
+
+private:
+    std::u16string mEmpty;
+    StdErrDiagnostics mDiagnostics;
+    NameMangler mNameMangler = NameMangler(NameManglerPolicy{});
+    SymbolTable mSymbolTable;
+};
+
+class LoadedApk {
+public:
+    LoadedApk(const Source& source, std::unique_ptr<io::IFileCollection> apk,
+              std::unique_ptr<ResourceTable> table) :
+            mSource(source), mApk(std::move(apk)), mTable(std::move(table)) {
+    }
+
+    io::IFileCollection* getFileCollection() {
+        return mApk.get();
+    }
+
+    ResourceTable* getResourceTable() {
+        return mTable.get();
+    }
+
+    const Source& getSource() {
+        return mSource;
+    }
+
+private:
+    Source mSource;
+    std::unique_ptr<io::IFileCollection> mApk;
+    std::unique_ptr<ResourceTable> mTable;
+
+    DISALLOW_COPY_AND_ASSIGN(LoadedApk);
+};
+
+static std::unique_ptr<LoadedApk> loadApkFromPath(IAaptContext* context, const StringPiece& path) {
+    Source source(path);
+    std::string error;
+    std::unique_ptr<io::ZipFileCollection> apk = io::ZipFileCollection::create(path, &error);
+    if (!apk) {
+        context->getDiagnostics()->error(DiagMessage(source) << error);
+        return {};
+    }
+
+    io::IFile* file = apk->findFile("resources.arsc");
+    if (!file) {
+        context->getDiagnostics()->error(DiagMessage(source) << "no resources.arsc found");
+        return {};
+    }
+
+    std::unique_ptr<io::IData> data = file->openAsData();
+    if (!data) {
+        context->getDiagnostics()->error(DiagMessage(source) << "could not open resources.arsc");
+        return {};
+    }
+
+    std::unique_ptr<ResourceTable> table = util::make_unique<ResourceTable>();
+    BinaryResourceParser parser(context, table.get(), source, data->data(), data->size());
+    if (!parser.parse()) {
+        return {};
+    }
+
+    return util::make_unique<LoadedApk>(source, std::move(apk), std::move(table));
+}
+
+static void emitDiffLine(const Source& source, const StringPiece& message) {
+    std::cerr << source << ": " << message << "\n";
+}
+
+static bool isSymbolVisibilityDifferent(const Symbol& symbolA, const Symbol& symbolB) {
+    return symbolA.state != symbolB.state;
+}
+
+template <typename Id>
+static bool isIdDiff(const Symbol& symbolA, const Maybe<Id>& idA,
+                     const Symbol& symbolB, const Maybe<Id>& idB) {
+    if (symbolA.state == SymbolState::kPublic || symbolB.state == SymbolState::kPublic) {
+        return idA != idB;
+    }
+    return false;
+}
+
+static bool emitResourceConfigValueDiff(IAaptContext* context,
+                                        LoadedApk* apkA,
+                                        ResourceTablePackage* pkgA,
+                                        ResourceTableType* typeA,
+                                        ResourceEntry* entryA,
+                                        ResourceConfigValue* configValueA,
+                                        LoadedApk* apkB,
+                                        ResourceTablePackage* pkgB,
+                                        ResourceTableType* typeB,
+                                        ResourceEntry* entryB,
+                                        ResourceConfigValue* configValueB) {
+    Value* valueA = configValueA->value.get();
+    Value* valueB = configValueB->value.get();
+    if (!valueA->equals(valueB)) {
+        std::stringstream strStream;
+        strStream << "value " << pkgA->name << ":" << typeA->type << "/" << entryA->name
+                << " config=" << configValueA->config << " does not match:\n";
+        valueA->print(&strStream);
+        strStream << "\n vs \n";
+        valueB->print(&strStream);
+        emitDiffLine(apkB->getSource(), strStream.str());
+        return true;
+    }
+    return false;
+}
+
+static bool emitResourceEntryDiff(IAaptContext* context,
+                                  LoadedApk* apkA,
+                                  ResourceTablePackage* pkgA,
+                                  ResourceTableType* typeA,
+                                  ResourceEntry* entryA,
+                                  LoadedApk* apkB,
+                                  ResourceTablePackage* pkgB,
+                                  ResourceTableType* typeB,
+                                  ResourceEntry* entryB) {
+    bool diff = false;
+    for (std::unique_ptr<ResourceConfigValue>& configValueA : entryA->values) {
+        ResourceConfigValue* configValueB = entryB->findValue(configValueA->config);
+        if (!configValueB) {
+            std::stringstream strStream;
+            strStream << "missing " << pkgA->name << ":" << typeA->type << "/" << entryA->name
+                    << " config=" << configValueA->config;
+            emitDiffLine(apkB->getSource(), strStream.str());
+            diff = true;
+        } else {
+            diff |= emitResourceConfigValueDiff(context, apkA, pkgA, typeA, entryA,
+                                                configValueA.get(), apkB, pkgB, typeB, entryB,
+                                                configValueB);
+        }
+    }
+
+    // Check for any newly added config values.
+    for (std::unique_ptr<ResourceConfigValue>& configValueB : entryB->values) {
+        ResourceConfigValue* configValueA = entryA->findValue(configValueB->config);
+        if (!configValueA) {
+            std::stringstream strStream;
+            strStream << "new config " << pkgB->name << ":" << typeB->type << "/" << entryB->name
+                    << " config=" << configValueB->config;
+            emitDiffLine(apkB->getSource(), strStream.str());
+            diff = true;
+        }
+    }
+    return false;
+}
+
+static bool emitResourceTypeDiff(IAaptContext* context,
+                                 LoadedApk* apkA,
+                                 ResourceTablePackage* pkgA,
+                                 ResourceTableType* typeA,
+                                 LoadedApk* apkB,
+                                 ResourceTablePackage* pkgB,
+                                 ResourceTableType* typeB) {
+    bool diff = false;
+    for (std::unique_ptr<ResourceEntry>& entryA : typeA->entries) {
+        ResourceEntry* entryB = typeB->findEntry(entryA->name);
+        if (!entryB) {
+            std::stringstream strStream;
+            strStream << "missing " << pkgA->name << ":" << typeA->type << "/" << entryA->name;
+            emitDiffLine(apkB->getSource(), strStream.str());
+            diff = true;
+        } else {
+            if (isSymbolVisibilityDifferent(entryA->symbolStatus, entryB->symbolStatus)) {
+                std::stringstream strStream;
+                strStream << pkgA->name << ":" << typeA->type << "/" << entryA->name
+                        << " has different visibility (";
+                if (entryB->symbolStatus.state == SymbolState::kPublic) {
+                    strStream << "PUBLIC";
+                } else {
+                    strStream << "PRIVATE";
+                }
+                strStream << " vs ";
+                if (entryA->symbolStatus.state == SymbolState::kPublic) {
+                    strStream << "PUBLIC";
+                } else {
+                    strStream << "PRIVATE";
+                }
+                strStream << ")";
+                emitDiffLine(apkB->getSource(), strStream.str());
+                diff = true;
+            } else if (isIdDiff(entryA->symbolStatus, entryA->id,
+                                entryB->symbolStatus, entryB->id)) {
+                std::stringstream strStream;
+                strStream << pkgA->name << ":" << typeA->type << "/" << entryA->name
+                        << " has different public ID (";
+                if (entryB->id) {
+                    strStream << "0x" << std::hex << entryB->id.value();
+                } else {
+                    strStream << "none";
+                }
+                strStream << " vs ";
+                if (entryA->id) {
+                    strStream << "0x " << std::hex << entryA->id.value();
+                } else {
+                    strStream << "none";
+                }
+                strStream << ")";
+                emitDiffLine(apkB->getSource(), strStream.str());
+                diff = true;
+            }
+            diff |= emitResourceEntryDiff(context, apkA, pkgA, typeA, entryA.get(),
+                                          apkB, pkgB, typeB, entryB);
+        }
+    }
+
+    // Check for any newly added entries.
+    for (std::unique_ptr<ResourceEntry>& entryB : typeB->entries) {
+        ResourceEntry* entryA = typeA->findEntry(entryB->name);
+        if (!entryA) {
+            std::stringstream strStream;
+            strStream << "new entry " << pkgB->name << ":" << typeB->type << "/" << entryB->name;
+            emitDiffLine(apkB->getSource(), strStream.str());
+            diff = true;
+        }
+    }
+    return diff;
+}
+
+static bool emitResourcePackageDiff(IAaptContext* context, LoadedApk* apkA,
+                                    ResourceTablePackage* pkgA,
+                                    LoadedApk* apkB, ResourceTablePackage* pkgB) {
+    bool diff = false;
+    for (std::unique_ptr<ResourceTableType>& typeA : pkgA->types) {
+        ResourceTableType* typeB = pkgB->findType(typeA->type);
+        if (!typeB) {
+            std::stringstream strStream;
+            strStream << "missing " << pkgA->name << ":" << typeA->type;
+            emitDiffLine(apkA->getSource(), strStream.str());
+            diff = true;
+        } else {
+            if (isSymbolVisibilityDifferent(typeA->symbolStatus, typeB->symbolStatus)) {
+                std::stringstream strStream;
+                strStream << pkgA->name << ":" << typeA->type << " has different visibility (";
+                if (typeB->symbolStatus.state == SymbolState::kPublic) {
+                    strStream << "PUBLIC";
+                } else {
+                    strStream << "PRIVATE";
+                }
+                strStream << " vs ";
+                if (typeA->symbolStatus.state == SymbolState::kPublic) {
+                    strStream << "PUBLIC";
+                } else {
+                    strStream << "PRIVATE";
+                }
+                strStream << ")";
+                emitDiffLine(apkB->getSource(), strStream.str());
+                diff = true;
+            } else if (isIdDiff(typeA->symbolStatus, typeA->id, typeB->symbolStatus, typeB->id)) {
+                std::stringstream strStream;
+                strStream << pkgA->name << ":" << typeA->type << " has different public ID (";
+                if (typeB->id) {
+                    strStream << "0x" << std::hex << typeB->id.value();
+                } else {
+                    strStream << "none";
+                }
+                strStream << " vs ";
+                if (typeA->id) {
+                    strStream << "0x " << std::hex << typeA->id.value();
+                } else {
+                    strStream << "none";
+                }
+                strStream << ")";
+                emitDiffLine(apkB->getSource(), strStream.str());
+                diff = true;
+            }
+            diff |= emitResourceTypeDiff(context, apkA, pkgA, typeA.get(), apkB, pkgB, typeB);
+        }
+    }
+
+    // Check for any newly added types.
+    for (std::unique_ptr<ResourceTableType>& typeB : pkgB->types) {
+        ResourceTableType* typeA = pkgA->findType(typeB->type);
+        if (!typeA) {
+            std::stringstream strStream;
+            strStream << "new type " << pkgB->name << ":" << typeB->type;
+            emitDiffLine(apkB->getSource(), strStream.str());
+            diff = true;
+        }
+    }
+    return diff;
+}
+
+static bool emitResourceTableDiff(IAaptContext* context, LoadedApk* apkA, LoadedApk* apkB) {
+    ResourceTable* tableA = apkA->getResourceTable();
+    ResourceTable* tableB = apkB->getResourceTable();
+
+    bool diff = false;
+    for (std::unique_ptr<ResourceTablePackage>& pkgA : tableA->packages) {
+        ResourceTablePackage* pkgB = tableB->findPackage(pkgA->name);
+        if (!pkgB) {
+            std::stringstream strStream;
+            strStream << "missing package " << pkgA->name;
+            emitDiffLine(apkB->getSource(), strStream.str());
+            diff = true;
+        } else {
+            if (pkgA->id != pkgB->id) {
+                std::stringstream strStream;
+                strStream << "package '" << pkgA->name << "' has different id (";
+                if (pkgB->id) {
+                    strStream << "0x" << std::hex << pkgB->id.value();
+                } else {
+                    strStream << "none";
+                }
+                strStream << " vs ";
+                if (pkgA->id) {
+                    strStream << "0x" << std::hex << pkgA->id.value();
+                } else {
+                    strStream << "none";
+                }
+                strStream << ")";
+                emitDiffLine(apkB->getSource(), strStream.str());
+                diff = true;
+            }
+            diff |= emitResourcePackageDiff(context, apkA, pkgA.get(), apkB, pkgB);
+        }
+    }
+
+    // Check for any newly added packages.
+    for (std::unique_ptr<ResourceTablePackage>& pkgB : tableB->packages) {
+        ResourceTablePackage* pkgA = tableA->findPackage(pkgB->name);
+        if (!pkgA) {
+            std::stringstream strStream;
+            strStream << "new package " << pkgB->name;
+            emitDiffLine(apkB->getSource(), strStream.str());
+            diff = true;
+        }
+    }
+    return diff;
+}
+
+int diff(const std::vector<StringPiece>& args) {
+    DiffContext context;
+
+    Flags flags;
+    if (!flags.parse("aapt2 diff", args, &std::cerr)) {
+        return 1;
+    }
+
+    if (flags.getArgs().size() != 2u) {
+        std::cerr << "must have two apks as arguments.\n\n";
+        flags.usage("aapt2 diff", &std::cerr);
+        return 1;
+    }
+
+    std::unique_ptr<LoadedApk> apkA = loadApkFromPath(&context, flags.getArgs()[0]);
+    std::unique_ptr<LoadedApk> apkB = loadApkFromPath(&context, flags.getArgs()[1]);
+    if (!apkA || !apkB) {
+        return 1;
+    }
+
+    if (emitResourceTableDiff(&context, apkA.get(), apkB.get())) {
+        // We emitted a diff, so return 1 (failure).
+        return 1;
+    }
+    return 0;
+}
+
+} // namespace aapt