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 // Component updates can be either differential updates or full updates. 6 // Full updates come in CRX format; differential updates come in CRX-style 7 // archives, but have a different magic number. They contain "commands.json", a 8 // list of commands for the patcher to follow. The patcher uses these commands, 9 // the other files in the archive, and the files from the existing installation 10 // of the component to create the contents of a full update, which is then 11 // installed normally. 12 // Component updates are specified by the 'codebasediff' attribute of an 13 // updatecheck response: 14 // <updatecheck codebase="http://example.com/extension_1.2.3.4.crx" 15 // hash="12345" size="9854" status="ok" version="1.2.3.4" 16 // prodversionmin="2.0.143.0" 17 // codebasediff="http://example.com/diff_1.2.3.4.crx" 18 // hashdiff="123" sizediff="101" 19 // fp="1.123"/> 20 // The component updater will attempt a differential update if it is available 21 // and allowed to, and fall back to a full update if it fails. 22 // 23 // After installation (diff or full), the component updater records "fp", the 24 // fingerprint of the installed files, to later identify the existing files to 25 // the server so that a proper differential update can be provided next cycle. 26 27 #ifndef COMPONENTS_UPDATE_CLIENT_COMPONENT_PATCHER_H_ 28 #define COMPONENTS_UPDATE_CLIENT_COMPONENT_PATCHER_H_ 29 30 #include <memory> 31 32 #include "base/callback_forward.h" 33 #include "base/macros.h" 34 #include "base/memory/ref_counted.h" 35 #include "base/values.h" 36 #include "components/update_client/component_unpacker.h" 37 38 namespace base { 39 class FilePath; 40 } 41 42 namespace update_client { 43 44 class CrxInstaller; 45 class DeltaUpdateOp; 46 class Patcher; 47 enum class UnpackerError; 48 49 // The type of a patch file. 50 enum PatchType { 51 kPatchTypeUnknown, 52 kPatchTypeCourgette, 53 kPatchTypeBsdiff, 54 }; 55 56 // Encapsulates a task for applying a differential update to a component. 57 class ComponentPatcher : public base::RefCountedThreadSafe<ComponentPatcher> { 58 public: 59 using Callback = base::OnceCallback<void(UnpackerError, int)>; 60 61 // Takes an unpacked differential CRX (|input_dir|) and a component installer, 62 // and sets up the class to create a new (non-differential) unpacked CRX. 63 // If |in_process| is true, patching will be done completely within the 64 // existing process. Otherwise, some steps of patching may be done 65 // out-of-process. 66 ComponentPatcher(const base::FilePath& input_dir, 67 const base::FilePath& unpack_dir, 68 scoped_refptr<CrxInstaller> installer, 69 scoped_refptr<Patcher> patcher); 70 71 // Starts patching files. This member function returns immediately, after 72 // posting a task to do the patching. When patching has been completed, 73 // |callback| will be called with the error codes if any error codes were 74 // encountered. 75 void Start(Callback callback); 76 77 private: 78 friend class base::RefCountedThreadSafe<ComponentPatcher>; 79 80 virtual ~ComponentPatcher(); 81 82 void StartPatching(); 83 84 void PatchNextFile(); 85 86 void DonePatchingFile(UnpackerError error, int extended_error); 87 88 void DonePatching(UnpackerError error, int extended_error); 89 90 const base::FilePath input_dir_; 91 const base::FilePath unpack_dir_; 92 scoped_refptr<CrxInstaller> installer_; 93 scoped_refptr<Patcher> patcher_; 94 Callback callback_; 95 std::unique_ptr<base::ListValue> commands_; 96 base::ListValue::const_iterator next_command_; 97 scoped_refptr<DeltaUpdateOp> current_operation_; 98 99 DISALLOW_COPY_AND_ASSIGN(ComponentPatcher); 100 }; 101 102 } // namespace update_client 103 104 #endif // COMPONENTS_UPDATE_CLIENT_COMPONENT_PATCHER_H_ 105