Add unzipping functionality to PluginVmImageManager

After PluginVm image is successfully downloaded it needs to be unzipped to a specific location. This CL adds unzipping functionality to the PluginVmImageManager so unzipping of the downloaded image could be called using manager and observer could receive events regarding status of the unzipping.

Bug: 904851
Test: unit_tests --gtest_filter="PluginVmImageManagerTest.*"
Change-Id: I005929fccbeec191951a054e303bc816e853285a
Reviewed-on: https://chromium-review.googlesource.com/c/1443171
Commit-Queue: Olya Kalitova <okalitova@chromium.org>
Reviewed-by: Igor <igorcov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#629931}

chrome/browser/chromeos/plugin_vm/plugin_vm_image_manager.h

@@ -5,11 +5,14 @@
 #ifndef CHROME_BROWSER_CHROMEOS_PLUGIN_VM_PLUGIN_VM_IMAGE_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_PLUGIN_VM_PLUGIN_VM_IMAGE_MANAGER_H_
 
+#include <memory>
 #include <string>
 
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
 #include "components/download/public/background_service/download_params.h"
 #include "components/keyed_service/core/keyed_service.h"
+#include "third_party/zlib/google/zip_reader.h"
 
 namespace base {
 template <typename T>
@@ -24,13 +27,17 @@ class Profile;
 
 namespace plugin_vm {
 
+constexpr char kCrosvmDir[] = "crosvm";
+constexpr char kPvmDir[] = "pvm";
+constexpr char kPluginVmImageDir[] = "default";
+
 // PluginVmImageManager is responsible for management of PluginVm image
 // including downloading this image from url specified by user policy and
-// unzipping downloaded image to the specified location.
+// unzipping downloaded image archive to the specified location.
 //
-// Only one download of PluginVm image at a time is allowed.
-// IsDownloading() should be called to check whether the manager is downloading
-// PluginVm image at the moment.
+// Only one PluginVm image at a time is allowed to be processed.
+// IsProcessingImage() should be called to check whether any image is being
+// processed at the moment.
 class PluginVmImageManager : public KeyedService {
  public:
   // Observer class for the PluginVm image related events.
@@ -40,23 +47,37 @@ class PluginVmImageManager : public KeyedService {
     virtual void OnDownloadStarted() = 0;
     virtual void OnProgressUpdated(
         base::Optional<double> fraction_complete) = 0;
-    virtual void OnDownloadCompleted(base::FilePath file_path) = 0;
+    virtual void OnDownloadCompleted() = 0;
     virtual void OnDownloadCancelled() = 0;
     // TODO(https://crbug.com/904851): Add failure reasons.
     virtual void OnDownloadFailed() = 0;
+    virtual void OnUnzipped() = 0;
+    virtual void OnUnzippingFailed() = 0;
   };
 
   explicit PluginVmImageManager(Profile* profile);
 
-  // Returns true if manager is downloading PluginVm image at the moment.
-  bool IsDownloading();
-  // Fails download in case IsDownloading() returns true otherwise starts a new
-  // download of PluginVm image.
+  // Returns true if manager is processing PluginVm image at the moment.
+  bool IsProcessingImage();
+  // Doesn't start to download PluginVm image and calls OnDownloadFailed() in
+  // case IsProcessingImage() returns true otherwise starts processing PluginVm
+  // image by downloading it.
   void StartDownload();
-  // Cancels the download of PluginVm image.
+  // Cancels the download of PluginVm image finishing the image processing.
+  // Downloaded PluginVm image archive is being deleted.
   void CancelDownload();
 
+  // Should be called when download of PluginVm image has been completed
+  // successfully. If called in other cases - unzipping is not started
+  // and OnUnzipped(false /* success */) is called.
+  void StartUnzipping();
+  // Sets flag that indicates that unzipping is cancelled. This flag is further
+  // checked in PluginVmImageWriterDelegate and in cases it is set to true
+  // OnUnzipped(false /* success */) called.
+  void CancelUnzipping();
+
   void SetObserver(Observer* observer);
+  void RemoveObserver();
 
   // Called by PluginVmImageDownloadClient.
   void OnDownloadStarted();
@@ -67,21 +88,69 @@ class PluginVmImageManager : public KeyedService {
 
   void SetDownloadServiceForTesting(
       download::DownloadService* download_service);
+  void SetDownloadedPluginVmImageArchiveForTesting(
+      base::FilePath downloaded_plugin_vm_image_archive);
   std::string GetCurrentDownloadGuidForTesting();
 
  private:
   Profile* profile_ = nullptr;
-  download::DownloadService* download_service_ = nullptr;
   Observer* observer_ = nullptr;
-  bool processing_download_ = false;
+  download::DownloadService* download_service_ = nullptr;
+  bool processing_image_ = false;
+  bool unzipping_cancelled_ = false;
   std::string current_download_guid_;
+  base::FilePath downloaded_plugin_vm_image_archive_;
+  base::FilePath plugin_vm_image_dir_;
+
+  class PluginVmImageWriterDelegate : public zip::WriterDelegate {
+   public:
+    explicit PluginVmImageWriterDelegate(
+        PluginVmImageManager* manager,
+        const base::FilePath& output_file_path);
+
+    // zip::WriterDelegate implementation.
+    bool PrepareOutput() override;
+    // If unzipping is cancelled returns false so unzipping would fail.
+    bool WriteBytes(const char* data, int num_bytes) override;
+    void SetTimeModified(const base::Time& time) override;
+
+   private:
+    PluginVmImageManager* manager_;
+    base::FilePath output_file_path_;
+    base::File output_file_;
+
+    DISALLOW_COPY_AND_ASSIGN(PluginVmImageWriterDelegate);
+  };
 
   ~PluginVmImageManager() override;
 
   download::DownloadParams GetDownloadParams();
 
-  void OnStarted(const std::string& download_guid,
-                 download::DownloadParams::StartResult start_result);
+  void OnStartDownload(const std::string& download_guid,
+                       download::DownloadParams::StartResult start_result);
+  bool IsDownloading();
+
+  bool UnzipDownloadedPluginVmImageArchive();
+  bool IsUnzippingCancelled();
+  // Callback arguments for unzipping function.
+  std::unique_ptr<zip::WriterDelegate> CreatePluginVmImageWriterDelegate(
+      const base::FilePath& entry_path);
+  bool CreateDirectory(const base::FilePath& entry_path);
+  bool FilterFilesInPluginVmImageArchive(const base::FilePath& file);
+
+  // Finishes the processing of PluginVm image. Deletes downloaded PluginVm
+  // image archive. In case success is false also deletes PluginVm image.
+  void OnUnzipped(bool success);
+
+  bool EnsureDownloadedPluginVmImageArchiveIsPresent();
+  // Creates directory for PluginVm image if one doesn't exists.
+  // Returns true in case directory has already existed or was successfully
+  // created and false otherwise.
+  bool EnsureDirectoryForPluginVmImageIsPresent();
+  void RemoveTemporaryPluginVmImageArchiveIfExists();
+  void RemovePluginVmImageDirectoryIfExists();
+
+  base::WeakPtrFactory<PluginVmImageManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginVmImageManager);
 };