1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef COMPONENTS_COMPONENT_UPDATER_DEFAULT_COMPONENT_INSTALLER_H_
6#define COMPONENTS_COMPONENT_UPDATER_DEFAULT_COMPONENT_INSTALLER_H_
7
8#include <stdint.h>
9#include <string>
10#include <vector>
11
12#include "base/compiler_specific.h"
13#include "base/macros.h"
14#include "base/memory/ref_counted.h"
15#include "base/memory/scoped_ptr.h"
16#include "base/threading/thread_checker.h"
17#include "base/values.h"
18#include "base/version.h"
19#include "components/component_updater/component_updater_service.h"
20
21namespace base {
22class FilePath;
23class SequencedTaskRunner;
24class SingleThreadTaskRunner;
25}  // namespace base
26
27namespace component_updater {
28
29// Components should use a DefaultComponentInstaller by defining a class that
30// implements the members of ComponentInstallerTraits, and then registering a
31// DefaultComponentInstaller that has been constructed with an instance of that
32// class.
33class ComponentInstallerTraits {
34 public:
35  virtual ~ComponentInstallerTraits();
36
37  // Verifies that a working installation resides within the directory specified
38  // by |dir|. |dir| is of the form <base directory>/<version>.
39  // Called only from a thread belonging to a blocking thread pool.
40  // The implementation of this function must be efficient since the function
41  // can be called when Chrome starts.
42  virtual bool VerifyInstallation(const base::FilePath& dir) const = 0;
43
44  // Returns true if the component can be automatically updated. Called once
45  // during component registration from the UI thread.
46  virtual bool CanAutoUpdate() const = 0;
47
48  // OnCustomInstall is called during the installation process. Components that
49  // require custom installation operations should implement them here.
50  // Returns false if a custom operation failed, and true otherwise.
51  // Called only from a thread belonging to a blocking thread pool.
52  virtual bool OnCustomInstall(const base::DictionaryValue& manifest,
53                               const base::FilePath& install_dir) = 0;
54
55  // ComponentReady is called in two cases:
56  //   1) After an installation is successfully completed.
57  //   2) During component registration if the component is already installed.
58  // In both cases the install is verified before this is called. This method
59  // is guaranteed to be called before any observers of the component are
60  // notified of a successful install, and is meant to support follow-on work
61  // such as updating paths elsewhere in Chrome. Called on the UI thread.
62  // |version| is the version of the component.
63  // |install_dir| is the path to the install directory for this version.
64  // |manifest| is the manifest for this version of the component.
65  virtual void ComponentReady(const base::Version& version,
66                              const base::FilePath& install_dir,
67                              scoped_ptr<base::DictionaryValue> manifest) = 0;
68
69  // Returns the directory that the installer will place versioned installs of
70  // the component into.
71  virtual base::FilePath GetBaseDirectory() const = 0;
72
73  // Returns the component's SHA2 hash as raw bytes.
74  virtual void GetHash(std::vector<uint8_t>* hash) const = 0;
75
76  // Returns the human-readable name of the component.
77  virtual std::string GetName() const = 0;
78};
79
80// A DefaultComponentInstaller is intended to be final, and not derived from.
81// Customization must be provided by passing a ComponentInstallerTraits object
82// to the constructor.
83class DefaultComponentInstaller : public ComponentInstaller {
84 public:
85  DefaultComponentInstaller(
86      scoped_ptr<ComponentInstallerTraits> installer_traits);
87
88  // Registers the component for update checks and installs.
89  void Register(ComponentUpdateService* cus);
90
91  // Overridden from ComponentInstaller:
92  virtual void OnUpdateError(int error) OVERRIDE;
93  virtual bool Install(const base::DictionaryValue& manifest,
94                       const base::FilePath& unpack_path) OVERRIDE;
95  virtual bool GetInstalledFile(const std::string& file,
96                                base::FilePath* installed_file) OVERRIDE;
97
98  virtual ~DefaultComponentInstaller();
99
100 private:
101  base::FilePath GetInstallDirectory();
102  bool InstallHelper(const base::DictionaryValue& manifest,
103                     const base::FilePath& unpack_path,
104                     const base::FilePath& install_path);
105  void StartRegistration(ComponentUpdateService* cus);
106  void FinishRegistration(ComponentUpdateService* cus);
107
108  base::Version current_version_;
109  std::string current_fingerprint_;
110  scoped_ptr<base::DictionaryValue> current_manifest_;
111  scoped_ptr<ComponentInstallerTraits> installer_traits_;
112  scoped_refptr<base::SequencedTaskRunner> task_runner_;
113
114  // Used to post responses back to the main thread. Initialized on the main
115  // loop but accessed from the task runner.
116  scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
117
118  base::ThreadChecker thread_checker_;
119
120  DISALLOW_COPY_AND_ASSIGN(DefaultComponentInstaller);
121};
122
123}  // namespace component_updater
124
125#endif  // COMPONENTS_COMPONENT_UPDATER_DEFAULT_COMPONENT_INSTALLER_H_
126