Revert 207805 "Differential updates for components. We are addin..."

trunk/src/chrome/browser/component_updater/component_patcher.h

-// Copyright 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// Component updates can be either differential updates or full updates.
-// Full updates come in CRX format; differential updates come in CRX-style
-// archives, but have a different magic number. They contain "commands.json", a
-// list of commands for the patcher to follow. The patcher uses these commands,
-// the other files in the archive, and the files from the existing installation
-// of the component to create the contents of a full update, which is then
-// installed normally.
-// Component updates are specified by the 'codebasediff' attribute of an
-// updatecheck response:
-//   <updatecheck codebase="http://example.com/extension_1.2.3.4.crx"
-//                hash="12345" size="9854" status="ok" version="1.2.3.4"
-//                prodversionmin="2.0.143.0"
-//                codebasediff="http://example.com/diff_1.2.3.4.crx"
-//                hashdiff="123" sizediff="101"
-//                fp="1.123" />
-// The component updater will attempt a differential update if it is available
-// and allowed to, and fall back to a full update if it fails.
-//
-// After installation (diff or full), the component updater records "fp", the
-// fingerprint of the installed files, to later identify the existing files to
-// the server so that a proper differential update can be provided next cycle.
-
-
-#ifndef CHROME_BROWSER_COMPONENT_UPDATER_COMPONENT_PATCHER_H_
-#define CHROME_BROWSER_COMPONENT_UPDATER_COMPONENT_PATCHER_H_
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "chrome/browser/component_updater/component_unpacker.h"
-
-namespace base {
-class FilePath;
-}
-
-class ComponentInstaller;
-
-// Applies a delta patch to a single file. Specifically, creates a file at
-// |output_file| using |input_file| patched according to the algorithm
-// specified by |patch_type| using |patch_file|. Sets the value of error to
-// the error code of the failing patch operation, if there is such a failure.
-class ComponentPatcher {
- public:
-  // The type of a patch file.
-  enum PatchType {
-    kPatchTypeUnknown,
-    kPatchTypeCourgette,
-    kPatchTypeBsdiff,
-  };
-
-  virtual ComponentUnpacker::Error Patch(PatchType patch_type,
-                                         const base::FilePath& input_file,
-                                         const base::FilePath& patch_file,
-                                         const base::FilePath& output_file,
-                                         int* error) = 0;
-  virtual ~ComponentPatcher() {}
-};
-
-class ComponentPatcherCrossPlatform : public ComponentPatcher {
- public:
-  ComponentPatcherCrossPlatform();
-  virtual ComponentUnpacker::Error Patch(PatchType patch_type,
-                                         const base::FilePath& input_file,
-                                         const base::FilePath& patch_file,
-                                         const base::FilePath& output_file,
-                                         int* error) OVERRIDE;
- private:
-  DISALLOW_COPY_AND_ASSIGN(ComponentPatcherCrossPlatform);
-};
-
-// This function takes an unpacked differential CRX (|input_dir|) and a
-// component installer, and creates a new (non-differential) unpacked CRX, which
-// is then installed normally.
-// The non-differential files are written into the |unpack_dir| directory.
-// Sets |error| to the error code of the first failing patch operation.
-ComponentUnpacker::Error DifferentialUpdatePatch(
-    const base::FilePath& input_dir,
-    const base::FilePath& unpack_dir,
-    ComponentPatcher* component_patcher,
-    ComponentInstaller* installer,
-    int* error);
-
-#endif  // CHROME_BROWSER_COMPONENT_UPDATER_COMPONENT_PATCHER_H_