Create a wrapper class for update package

Creates a new class handle the package in memory and package read from fd.
Define the new interface functions, and make approximate changes to the
verify and install functions.

Bug: 127071893
Test: unit tests pass, sideload a package
Change-Id: I66ab00654df92471184536fd147b237a86e9c5b5
diff --git a/package.h b/package.h
new file mode 100644
index 0000000..5eef9c9
--- /dev/null
+++ b/package.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2019 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 <stdint.h>
+
+#include <functional>
+#include <map>
+#include <memory>
+#include <string>
+#include <vector>
+
+#include <ziparchive/zip_archive.h>
+
+#include "verifier.h"
+
+// This class serves as a wrapper for an OTA update package. It aims to provide the common
+// interface for both packages loaded in memory and packages read from fd.
+class Package : public VerifierInterface {
+ public:
+  virtual ~Package() = default;
+
+  // Opens the package as a zip file and returns the ZipArchiveHandle.
+  virtual ZipArchiveHandle GetZipArchiveHandle() = 0;
+
+  // Updates the progress in fraction during package verification.
+  void SetProgress(float progress) override;
+
+  static std::unique_ptr<Package> CreateMemoryPackage(
+      const std::string& path, const std::function<void(float)>& set_progress);
+
+  static std::unique_ptr<Package> CreateMemoryPackage(
+      std::vector<uint8_t> content, const std::function<void(float)>& set_progress);
+
+ protected:
+  // An optional function to update the progress.
+  std::function<void(float)> set_progress_;
+};