src/chrome/installer/util/set_reg_value_work_item.cc

   1 // Copyright (c) 2011 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 "chrome/installer/util/set_reg_value_work_item.h"
   6
   7 #include "base/logging.h"
   8 #include "base/strings/string_util.h"
   9 #include "base/win/registry.h"
  10 #include "chrome/installer/util/logging_installer.h"
  11
  12 SetRegValueWorkItem::~SetRegValueWorkItem() {
  13 }
  14
  15 SetRegValueWorkItem::SetRegValueWorkItem(HKEY predefined_root,
  16                                          const std::wstring& key_path,
  17                                          REGSAM wow64_access,
  18                                          const std::wstring& value_name,
  19                                          const std::wstring& value_data,
  20                                          bool overwrite)
  21     : predefined_root_(predefined_root),
  22       key_path_(key_path),
  23       value_name_(value_name),
  24       overwrite_(overwrite),
  25       wow64_access_(wow64_access),
  26       status_(SET_VALUE),
  27       type_(REG_SZ),
  28       previous_type_(0) {
  29   DCHECK(wow64_access == 0 ||
  30          wow64_access == KEY_WOW64_32KEY ||
  31          wow64_access == KEY_WOW64_64KEY);
  32   const uint8* data = reinterpret_cast<const uint8*>(value_data.c_str());
  33   value_.assign(data, data + (value_data.length() + 1) * sizeof(wchar_t));
  34 }
  35
  36 SetRegValueWorkItem::SetRegValueWorkItem(HKEY predefined_root,
  37                                          const std::wstring& key_path,
  38                                          REGSAM wow64_access,
  39                                          const std::wstring& value_name,
  40                                          DWORD value_data,
  41                                          bool overwrite)
  42     : predefined_root_(predefined_root),
  43       key_path_(key_path),
  44       value_name_(value_name),
  45       overwrite_(overwrite),
  46       wow64_access_(wow64_access),
  47       status_(SET_VALUE),
  48       type_(REG_DWORD),
  49       previous_type_(0) {
  50   DCHECK(wow64_access == 0 ||
  51          wow64_access == KEY_WOW64_32KEY ||
  52          wow64_access == KEY_WOW64_64KEY);
  53   const uint8* data = reinterpret_cast<const uint8*>(&value_data);
  54   value_.assign(data, data + sizeof(value_data));
  55 }
  56
  57 SetRegValueWorkItem::SetRegValueWorkItem(HKEY predefined_root,
  58                                          const std::wstring& key_path,
  59                                          REGSAM wow64_access,
  60                                          const std::wstring& value_name,
  61                                          int64 value_data,
  62                                          bool overwrite)
  63     : predefined_root_(predefined_root),
  64       key_path_(key_path),
  65       value_name_(value_name),
  66       overwrite_(overwrite),
  67       wow64_access_(wow64_access),
  68       status_(SET_VALUE),
  69       type_(REG_QWORD),
  70       previous_type_(0) {
  71   DCHECK(wow64_access == 0 ||
  72          wow64_access == KEY_WOW64_32KEY ||
  73          wow64_access == KEY_WOW64_64KEY);
  74   const uint8* data = reinterpret_cast<const uint8*>(&value_data);
  75   value_.assign(data, data + sizeof(value_data));
  76 }
  77
  78 bool SetRegValueWorkItem::Do() {
  79   LONG result = ERROR_SUCCESS;
  80   base::win::RegKey key;
  81   if (status_ != SET_VALUE) {
  82     // we already did something.
  83     VLOG(1) << "multiple calls to Do()";
  84     result = ERROR_CANTWRITE;
  85     return ignore_failure_;
  86   }
  87
  88   status_ = VALUE_UNCHANGED;
  89   result = key.Open(predefined_root_,
  90                     key_path_.c_str(),
  91                     KEY_READ | KEY_SET_VALUE | wow64_access_);
  92   if (result != ERROR_SUCCESS) {
  93     VLOG(1) << "can not open " << key_path_ << " error: " << result;
  94     return ignore_failure_;
  95   }
  96
  97   DWORD type = 0;
  98   DWORD size = 0;
  99   result = key.ReadValue(value_name_.c_str(), NULL, &size, &type);
 100   // If the value exists but we don't want to overwrite then there's
 101   // nothing more to do.
 102   if ((result != ERROR_FILE_NOT_FOUND) && !overwrite_) {
 103     return true;
 104   }
 105
 106   // If there's something to be saved, save it.
 107   if (result == ERROR_SUCCESS) {
 108     if (!size) {
 109       previous_type_ = type;
 110     } else {
 111       previous_value_.resize(size);
 112       result = key.ReadValue(value_name_.c_str(), &previous_value_[0], &size,
 113                              &previous_type_);
 114       if (result != ERROR_SUCCESS) {
 115         previous_value_.clear();
 116         VLOG(1) << "Failed to save original value. Error: " << result;
 117       }
 118     }
 119   }
 120
 121   result = key.WriteValue(value_name_.c_str(), &value_[0],
 122                           static_cast<DWORD>(value_.size()), type_);
 123   if (result != ERROR_SUCCESS) {
 124     VLOG(1) << "Failed to write value " << key_path_ << " error: " << result;
 125     return ignore_failure_;
 126   }
 127
 128   status_ = previous_type_ ? VALUE_OVERWRITTEN : NEW_VALUE_CREATED;
 129   return true;
 130 }
 131
 132 void SetRegValueWorkItem::Rollback() {
 133   if (ignore_failure_)
 134     return;
 135
 136   if (status_ == SET_VALUE || status_ == VALUE_ROLL_BACK)
 137     return;
 138
 139   if (status_ == VALUE_UNCHANGED) {
 140     status_ = VALUE_ROLL_BACK;
 141     VLOG(1) << "rollback: setting unchanged, nothing to do";
 142     return;
 143   }
 144
 145   base::win::RegKey key;
 146   LONG result = key.Open(
 147       predefined_root_, key_path_.c_str(), KEY_SET_VALUE | wow64_access_);
 148   if (result != ERROR_SUCCESS) {
 149     VLOG(1) << "rollback: can not open " << key_path_ << " error: " << result;
 150     return;
 151   }
 152
 153   if (status_ == NEW_VALUE_CREATED) {
 154     result = key.DeleteValue(value_name_.c_str());
 155     VLOG(1) << "rollback: deleting " << value_name_ << " error: " << result;
 156   } else if (status_ == VALUE_OVERWRITTEN) {
 157     const unsigned char* previous_value =
 158         previous_value_.empty() ? NULL : &previous_value_[0];
 159     result = key.WriteValue(value_name_.c_str(), previous_value,
 160                             static_cast<DWORD>(previous_value_.size()),
 161                             previous_type_);
 162     VLOG(1) << "rollback: restoring " << value_name_ << " error: " << result;
 163   } else {
 164     NOTREACHED();
 165   }
 166
 167   status_ = VALUE_ROLL_BACK;
 168 }