components/component_updater/component_patcher.cc

   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 #include "components/component_updater/component_patcher.h"
   6
   7 #include <string>
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/bind.h"
  12 #include "base/file_util.h"
  13 #include "base/files/file_path.h"
  14 #include "base/json/json_file_value_serializer.h"
  15 #include "base/location.h"
  16 #include "base/memory/weak_ptr.h"
  17 #include "base/values.h"
  18 #include "components/component_updater/component_patcher_operation.h"
  19 #include "components/component_updater/component_updater_service.h"
  20
  21 namespace component_updater {
  22
  23 namespace {
  24
  25 // Deserialize the commands file (present in delta update packages). The top
  26 // level must be a list.
  27 base::ListValue* ReadCommands(const base::FilePath& unpack_path) {
  28   const base::FilePath commands =
  29       unpack_path.Append(FILE_PATH_LITERAL("commands.json"));
  30   if (!base::PathExists(commands))
  31     return NULL;
  32
  33   JSONFileValueSerializer serializer(commands);
  34   scoped_ptr<base::Value> root(serializer.Deserialize(NULL, NULL));
  35
  36   return (root.get() && root->IsType(base::Value::TYPE_LIST))
  37              ? static_cast<base::ListValue*>(root.release())
  38              : NULL;
  39 }
  40
  41 }  // namespace
  42
  43 ComponentPatcher::ComponentPatcher(
  44     const base::FilePath& input_dir,
  45     const base::FilePath& unpack_dir,
  46     ComponentInstaller* installer,
  47     scoped_refptr<OutOfProcessPatcher> out_of_process_patcher,
  48     scoped_refptr<base::SequencedTaskRunner> task_runner)
  49     : input_dir_(input_dir),
  50       unpack_dir_(unpack_dir),
  51       installer_(installer),
  52       out_of_process_patcher_(out_of_process_patcher),
  53       task_runner_(task_runner) {
  54 }
  55
  56 ComponentPatcher::~ComponentPatcher() {
  57 }
  58
  59 void ComponentPatcher::Start(const ComponentUnpacker::Callback& callback) {
  60   callback_ = callback;
  61   task_runner_->PostTask(FROM_HERE,
  62                          base::Bind(&ComponentPatcher::StartPatching,
  63                                     scoped_refptr<ComponentPatcher>(this)));
  64 }
  65
  66 void ComponentPatcher::StartPatching() {
  67   commands_.reset(ReadCommands(input_dir_));
  68   if (!commands_.get()) {
  69     DonePatching(ComponentUnpacker::kDeltaBadCommands, 0);
  70   } else {
  71     next_command_ = commands_->begin();
  72     PatchNextFile();
  73   }
  74 }
  75
  76 void ComponentPatcher::PatchNextFile() {
  77   if (next_command_ == commands_->end()) {
  78     DonePatching(ComponentUnpacker::kNone, 0);
  79     return;
  80   }
  81   if (!(*next_command_)->IsType(base::Value::TYPE_DICTIONARY)) {
  82     DonePatching(ComponentUnpacker::kDeltaBadCommands, 0);
  83     return;
  84   }
  85   const base::DictionaryValue* command_args =
  86       static_cast<base::DictionaryValue*>(*next_command_);
  87
  88   std::string operation;
  89   if (command_args->GetString(kOp, &operation)) {
  90     current_operation_ =
  91         CreateDeltaUpdateOp(operation, out_of_process_patcher_);
  92   }
  93
  94   if (!current_operation_.get()) {
  95     DonePatching(ComponentUnpacker::kDeltaUnsupportedCommand, 0);
  96     return;
  97   }
  98   current_operation_->Run(command_args,
  99                           input_dir_,
 100                           unpack_dir_,
 101                           installer_,
 102                           base::Bind(&ComponentPatcher::DonePatchingFile,
 103                                      scoped_refptr<ComponentPatcher>(this)),
 104                           task_runner_);
 105 }
 106
 107 void ComponentPatcher::DonePatchingFile(ComponentUnpacker::Error error,
 108                                         int extended_error) {
 109   if (error != ComponentUnpacker::kNone) {
 110     DonePatching(error, extended_error);
 111   } else {
 112     ++next_command_;
 113     PatchNextFile();
 114   }
 115 }
 116
 117 void ComponentPatcher::DonePatching(ComponentUnpacker::Error error,
 118                                     int extended_error) {
 119   current_operation_ = NULL;
 120   task_runner_->PostTask(FROM_HERE,
 121                          base::Bind(callback_, error, extended_error));
 122   callback_.Reset();
 123 }
 124
 125 }  // namespace component_updater