[cros] RlzValueStore implementation for ChromeOS.

rlz/chromeos/lib/rlz_value_store_chromeos.cc

 // Copyright (c) 2012 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.
 
-#include "rlz/win/lib/rlz_value_store_registry.h"
-
-#include "base/win/registry.h"
-#include "base/stringprintf.h"
-#include "base/utf_string_conversions.h"
-#include "rlz/lib/assert.h"
+#include "rlz/chromeos/lib/rlz_value_store_chromeos.h"
+
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/logging.h"
+#include "base/memory/singleton.h"
+#include "base/prefs/json_pref_store.h"
+#include "base/sequenced_task_runner.h"
+#include "base/string_number_conversions.h"
+#include "base/values.h"
 #include "rlz/lib/lib_values.h"
+#include "rlz/lib/recursive_lock.h"
 #include "rlz/lib/rlz_lib.h"
-#include "rlz/lib/string_utils.h"
-#include "rlz/win/lib/registry_util.h"
 
 namespace rlz_lib {
 
 namespace {
 
-//
-// Registry keys:
-//
-//   RLZ's are stored as:
-//   <AccessPointName>  = <RLZ value> @ kRootKey\kLibKeyName\kRlzsSubkeyName.
-//
-//   Events are stored as:
-//   <AccessPointName><EventName> = 1 @
-//   HKCU\kLibKeyName\kEventsSubkeyName\GetProductName(product).
-//
-//   The OEM Deal Confirmation Code (DCC) is stored as
-//   kDccValueName = <DCC value> @ HKLM\kLibKeyName
-//
-//   The last ping time, per product is stored as:
-//   GetProductName(product) = <last ping time> @
-//   HKCU\kLibKeyName\kPingTimesSubkeyName.
-//
-// The server does not care about any of these constants.
-//
-const char kLibKeyName[]               = "Software\\Google\\Common\\Rlz";
-const wchar_t kGoogleKeyName[]         = L"Software\\Google";
-const wchar_t kGoogleCommonKeyName[]   = L"Software\\Google\\Common";
-const char kRlzsSubkeyName[]           = "RLZs";
-const char kEventsSubkeyName[]         = "Events";
-const char kStatefulEventsSubkeyName[] = "StatefulEvents";
-const char kPingTimesSubkeyName[]      = "PTimes";
-
-std::wstring GetWideProductName(Product product) {
-  return ASCIIToWide(GetProductName(product));
-}
-
-void AppendBrandToString(std::string* str) {
-  std::string brand(SupplementaryBranding::GetBrand());
-  if (!brand.empty())
-    base::StringAppendF(str, "\\_%s", brand.c_str());
-}
-
-// Function to get the specific registry keys.
-bool GetRegKey(const char* name, REGSAM access, base::win::RegKey* key) {
-  std::string key_location;
-  base::StringAppendF(&key_location, "%s\\%s", kLibKeyName, name);
-  AppendBrandToString(&key_location);
-
-  LONG ret = ERROR_SUCCESS;
-  if (access & (KEY_SET_VALUE | KEY_CREATE_SUB_KEY | KEY_CREATE_LINK)) {
-    ret = key->Create(HKEY_CURRENT_USER, ASCIIToWide(key_location).c_str(),
-                      access);
-  } else {
-    ret = key->Open(HKEY_CURRENT_USER, ASCIIToWide(key_location).c_str(),
-                    access);
-  }
-
-  return ret == ERROR_SUCCESS;
-}
-
-bool GetPingTimesRegKey(REGSAM access, base::win::RegKey* key) {
-  return GetRegKey(kPingTimesSubkeyName, access, key);
-}
-
-
-bool GetEventsRegKey(const char* event_type,
-                     const rlz_lib::Product* product,
-                     REGSAM access, base::win::RegKey* key) {
-  std::string key_location;
-  base::StringAppendF(&key_location, "%s\\%s", kLibKeyName,
-                      event_type);
-  AppendBrandToString(&key_location);
-
-  if (product != NULL) {
-    std::string product_name = GetProductName(*product);
-    if (product_name.empty())
-      return false;
-
-    base::StringAppendF(&key_location, "\\%s", product_name.c_str());
-  }
-
-  LONG ret = ERROR_SUCCESS;
-  if (access & (KEY_SET_VALUE | KEY_CREATE_SUB_KEY | KEY_CREATE_LINK)) {
-    ret = key->Create(HKEY_CURRENT_USER, ASCIIToWide(key_location).c_str(),
-                      access);
-  } else {
-    ret = key->Open(HKEY_CURRENT_USER, ASCIIToWide(key_location).c_str(),
-                    access);
-  }
-
-  return ret == ERROR_SUCCESS;
-}
-
-bool GetAccessPointRlzsRegKey(REGSAM access, base::win::RegKey* key) {
-  return GetRegKey(kRlzsSubkeyName, access, key);
-}
-
-bool ClearAllProductEventValues(rlz_lib::Product product, const char* key) {
-  std::wstring product_name = GetWideProductName(product);
-  if (product_name.empty())
-    return false;
-
-  base::win::RegKey reg_key;
-  GetEventsRegKey(key, NULL, KEY_WRITE, &reg_key);
-  reg_key.DeleteKey(product_name.c_str());
-
-  // Verify that the value no longer exists.
-  base::win::RegKey product_events(
-      reg_key.Handle(), product_name.c_str(), KEY_READ);
-  if (product_events.Valid()) {
-    ASSERT_STRING("ClearAllProductEvents: Key deletion failed");
-    return false;
-  }
-
-  return true;
-}
-
-// Deletes a registry key if it exists and has no subkeys or values.
-// TODO: Move this to a registry_utils file and add unittest.
-bool DeleteKeyIfEmpty(HKEY root_key, const wchar_t* key_name) {
-  if (!key_name) {
-    ASSERT_STRING("DeleteKeyIfEmpty: key_name is NULL");
-    return false;
-  } else {  // Scope needed for RegKey
-    base::win::RegKey key(root_key, key_name, KEY_READ);
-    if (!key.Valid())
-      return true;  // Key does not exist - nothing to do.
-
-    base::win::RegistryKeyIterator key_iter(root_key, key_name);
-    if (key_iter.SubkeyCount() > 0)
-      return true;  // Not empty, so nothing to do
-
-    base::win::RegistryValueIterator value_iter(root_key, key_name);
-    if (value_iter.ValueCount() > 0)
-      return true;  // Not empty, so nothing to do
-  }
-
-  // The key is empty - delete it now.
-  base::win::RegKey key(root_key, L"", KEY_WRITE);
-  return key.DeleteKey(key_name) == ERROR_SUCCESS;
+// Product names.
+const char kProductChrome[] = "chrome";
+const char kProductOther[] = "other";
+
+// Key names.
+const char kPingTimeKey[] = "ping_time";
+const char kAccessPointKey[] = "access_points";
+const char kProductEventKey[] = "product_events";
+const char kStatefulEventKey[] = "stateful_events";
+
+// Brand name used when there is no supplementary brand name.
+const char kNoSupplementaryBrand[] = "_";
+
+// RLZ store filename.
+const FilePath::CharType kRLZDataFileName[] = FILE_PATH_LITERAL("RLZ Data");
+
+// RLZ store path for testing.
+FilePath g_testing_rlz_store_path_;
+
+// Returns file path of the RLZ storage.
+FilePath GetRlzStorePath() {
+  return g_testing_rlz_store_path_.empty() ?
+      file_util::GetHomeDir().Append(kRLZDataFileName) :
+      g_testing_rlz_store_path_.Append(kRLZDataFileName);
+}
+
+// Returns the dictionary key for storing access point-related prefs.
+std::string GetKeyName(std::string key, AccessPoint access_point) {
+  std::string brand = SupplementaryBranding::GetBrand();
+  if (brand.empty())
+    brand = kNoSupplementaryBrand;
+  return key + "." + GetAccessPointName(access_point) + "." + brand;
+}
+
+// Returns the dictionary key for storing product-related prefs.
+std::string GetKeyName(std::string key, Product product) {
+  std::string brand = SupplementaryBranding::GetBrand();
+  if (brand.empty())
+    brand = kNoSupplementaryBrand;
+  return key + "." + GetProductName(product) + "." + brand;
 }
 
 }  // namespace
 
 // static
-std::wstring RlzValueStoreRegistry::GetWideLibKeyName() {
-  return ASCIIToWide(kLibKeyName);
-}
-
-bool RlzValueStoreRegistry::HasAccess(AccessType type) {
-  return HasUserKeyAccess(type == kWriteAccess);
-}
-
-bool RlzValueStoreRegistry::WritePingTime(Product product, int64 time) {
-  base::win::RegKey key;
-  std::wstring product_name = GetWideProductName(product);
-  return GetPingTimesRegKey(KEY_WRITE, &key) &&
-      key.WriteValue(product_name.c_str(), &time, sizeof(time),
-                     REG_QWORD) == ERROR_SUCCESS;
-}
-
-bool RlzValueStoreRegistry::ReadPingTime(Product product, int64* time) {
-  base::win::RegKey key;
-  std::wstring product_name = GetWideProductName(product);
-  return GetPingTimesRegKey(KEY_READ, &key) &&
-      key.ReadInt64(product_name.c_str(), time) == ERROR_SUCCESS;
-}
-
-bool RlzValueStoreRegistry::ClearPingTime(Product product) {
-  base::win::RegKey key;
-  GetPingTimesRegKey(KEY_WRITE, &key);
-
-  std::wstring product_name = GetWideProductName(product);
-  key.DeleteValue(product_name.c_str());
-
-  // Verify deletion.
-  uint64 value;
-  DWORD size = sizeof(value);
-  if (key.ReadValue(
-        product_name.c_str(), &value, &size, NULL) == ERROR_SUCCESS) {
-    ASSERT_STRING("RlzValueStoreRegistry::ClearPingTime: Failed to delete.");
-    return false;
-  }
-
-  return true;
-}
-
-bool RlzValueStoreRegistry::WriteAccessPointRlz(AccessPoint access_point,
+base::SequencedTaskRunner* RlzValueStoreChromeOS::io_task_runner_ = NULL;
+
+// static
+bool RlzValueStoreChromeOS::created_;
+
+// static
+RlzValueStoreChromeOS* RlzValueStoreChromeOS::GetInstance() {
+  return Singleton<RlzValueStoreChromeOS>::get();
+}
+
+// static
+void RlzValueStoreChromeOS::SetIOTaskRunner(
+    base::SequencedTaskRunner* io_task_runner) {
+  io_task_runner_ = io_task_runner;
+  // Make sure |io_task_runner_| lives until constructor is called.
+  io_task_runner_->AddRef();
+}
+
+// static
+void RlzValueStoreChromeOS::ResetForTesting() {
+  // Make sure we don't create an instance if it didn't exist.
+  if (created_)
+    GetInstance()->ReadPrefs();
+}
+
+RlzValueStoreChromeOS::RlzValueStoreChromeOS() {
+  ReadPrefs();
+  created_ = true;
+}
+
+RlzValueStoreChromeOS::~RlzValueStoreChromeOS() {
+}
+
+bool RlzValueStoreChromeOS::HasAccess(AccessType type) {
+  return type == kReadAccess || !rlz_store_->ReadOnly();
+}
+
+bool RlzValueStoreChromeOS::WritePingTime(Product product, int64 time) {
+  std::string value = base::Int64ToString(time);
+  rlz_store_->SetValue(GetKeyName(kPingTimeKey, product),
+                       base::Value::CreateStringValue(value));
+  return true;
+}
+
+bool RlzValueStoreChromeOS::ReadPingTime(Product product, int64* time) {
+  const base::Value* value = NULL;
+  rlz_store_->GetValue(GetKeyName(kPingTimeKey, product), &value);
+  std::string s_value;
+  return value && value->GetAsString(&s_value) &&
+      base::StringToInt64(s_value, time);
+}
+
+bool RlzValueStoreChromeOS::ClearPingTime(Product product) {
+  rlz_store_->RemoveValue(GetKeyName(kPingTimeKey, product));
+  return true;
+}
+
+bool RlzValueStoreChromeOS::WriteAccessPointRlz(AccessPoint access_point,
                                                 const char* new_rlz) {
-  const char* access_point_name = GetAccessPointName(access_point);
-  if (!access_point_name)
-    return false;
-
-  std::wstring access_point_name_wide(ASCIIToWide(access_point_name));
-  base::win::RegKey key;
-  GetAccessPointRlzsRegKey(KEY_WRITE, &key);
-
-  if (!RegKeyWriteValue(key, access_point_name_wide.c_str(), new_rlz)) {
-    ASSERT_STRING("SetAccessPointRlz: Could not write the new RLZ value");
-    return false;
-  }
-  return true;
-}
-
-bool RlzValueStoreRegistry::ReadAccessPointRlz(AccessPoint access_point,
+  rlz_store_->SetValue(
+      GetKeyName(kAccessPointKey, access_point),
+      base::Value::CreateStringValue(new_rlz));
+  return true;
+}
+
+bool RlzValueStoreChromeOS::ReadAccessPointRlz(AccessPoint access_point,
                                                char* rlz,
                                                size_t rlz_size) {
-  const char* access_point_name = GetAccessPointName(access_point);
-  if (!access_point_name)
+  const base::Value* value = NULL;
+  rlz_store_->GetValue(
+      GetKeyName(kAccessPointKey, access_point), &value);
+  std::string s_value;
+  if (value)
+    value->GetAsString(&s_value);
+  if (s_value.size() < rlz_size) {
+    strncpy(rlz, s_value.c_str(), rlz_size);
+    return true;
+  }
+  if (rlz_size > 0)
+    *rlz = '\0';
+  return false;
+}
+
+bool RlzValueStoreChromeOS::ClearAccessPointRlz(AccessPoint access_point) {
+  rlz_store_->RemoveValue(
+      GetKeyName(kAccessPointKey, access_point));
+  return true;
+}
+
+bool RlzValueStoreChromeOS::AddProductEvent(Product product,
+                                            const char* event_rlz) {
+  return AddValueToList(GetKeyName(kProductEventKey, product),
+                        base::Value::CreateStringValue(event_rlz));
+}
+
+bool RlzValueStoreChromeOS::ReadProductEvents(
+    Product product,
+    std::vector<std::string>* events) {
+  base::ListValue* events_list = GetList(GetKeyName(kProductEventKey, product));
+  if (!events_list)
     return false;
-
-  size_t size = rlz_size;
-  base::win::RegKey key;
-  GetAccessPointRlzsRegKey(KEY_READ, &key);
-  if (!RegKeyReadValue(key, ASCIIToWide(access_point_name).c_str(),
-                       rlz, &size)) {
-    rlz[0] = 0;
-    if (size > rlz_size) {
-      ASSERT_STRING("GetAccessPointRlz: Insufficient buffer size");
-      return false;
-    }
-  }
-  return true;
-}
-
-bool RlzValueStoreRegistry::ClearAccessPointRlz(AccessPoint access_point) {
-  const char* access_point_name = GetAccessPointName(access_point);
-  if (!access_point_name)
+  events->clear();
+  for (size_t i = 0; i < events_list->GetSize(); ++i) {
+    std::string event;
+    if (events_list->GetString(i, &event))
+      events->push_back(event);
+  }
+  return true;
+}
+
+bool RlzValueStoreChromeOS::ClearProductEvent(Product product,
+                                              const char* event_rlz) {
+  base::StringValue event_value(event_rlz);
+  return RemoveValueFromList(GetKeyName(kProductEventKey, product),
+                             event_value);
+}
+
+bool RlzValueStoreChromeOS::ClearAllProductEvents(Product product) {
+  rlz_store_->RemoveValue(GetKeyName(kProductEventKey, product));
+  return true;
+}
+
+bool RlzValueStoreChromeOS::AddStatefulEvent(Product product,
+                                             const char* event_rlz) {
+  return AddValueToList(GetKeyName(kStatefulEventKey, product),
+                        base::Value::CreateStringValue(event_rlz));
+}
+
+bool RlzValueStoreChromeOS::IsStatefulEvent(Product product,
+                                            const char* event_rlz) {
+  base::ListValue* events_list =
+      GetList(GetKeyName(kStatefulEventKey, product));
+  base::StringValue event_value(event_rlz);
+  return events_list && events_list->Find(event_value) != events_list->end();
+}
+
+bool RlzValueStoreChromeOS::ClearAllStatefulEvents(Product product) {
+  rlz_store_->RemoveValue(GetKeyName(kStatefulEventKey, product));
+  return true;
+}
+
+void RlzValueStoreChromeOS::CollectGarbage() {
+  NOTIMPLEMENTED();
+}
+
+void RlzValueStoreChromeOS::ReadPrefs() {
+  DCHECK(io_task_runner_)
+      << "Calling GetInstance or ResetForTesting before SetIOTaskRunner?";
+  rlz_store_ = new JsonPrefStore(GetRlzStorePath(), io_task_runner_);
+  rlz_store_->ReadPrefs();
+  switch (rlz_store_->GetReadError()) {
+    case PersistentPrefStore::PREF_READ_ERROR_NONE:
+    case PersistentPrefStore::PREF_READ_ERROR_NO_FILE:
+      break;
+    default:
+      LOG(ERROR) << "Error read RLZ store: " << rlz_store_->GetReadError();
+  }
+  // Restore refcount modified by SetIOTaskRunner().
+  io_task_runner_->Release();
+  io_task_runner_ = NULL;
+}
+
+base::ListValue* RlzValueStoreChromeOS::GetList(std::string list_name) {
+  base::Value* list_value = NULL;
+  rlz_store_->GetMutableValue(list_name, &list_value);
+  base::ListValue* list = NULL;
+  if (!list_value || !list_value->GetAsList(&list))
+    return NULL;
+  return list;
+}
+
+bool RlzValueStoreChromeOS::AddValueToList(std::string list_name,
+                                           base::Value* value) {
+  base::ListValue* list = GetList(list_name);
+  if (!list) {
+    list = new base::ListValue;
+    rlz_store_->SetValue(list_name, list);
+  }
+  if (list->AppendIfNotPresent(value))
+    rlz_store_->ReportValueChanged(list_name);
+  return true;
+}
+
+bool RlzValueStoreChromeOS::RemoveValueFromList(std::string list_name,
+                                                const base::Value& value) {
+  base::ListValue* list = GetList(list_name);
+  if (!list)
     return false;
-
-  std::wstring access_point_name_wide(ASCIIToWide(access_point_name));
-  base::win::RegKey key;
-  GetAccessPointRlzsRegKey(KEY_WRITE, &key);
-
-  key.DeleteValue(access_point_name_wide.c_str());
-
-  // Verify deletion.
-  DWORD value;
-  if (key.ReadValueDW(access_point_name_wide.c_str(), &value) ==
-      ERROR_SUCCESS) {
-    ASSERT_STRING("SetAccessPointRlz: Could not clear the RLZ value.");
-    return false;
-  }
-  return true;
-}
-
-bool RlzValueStoreRegistry::AddProductEvent(Product product,
-                                            const char* event_rlz) {
-  std::wstring event_rlz_wide(ASCIIToWide(event_rlz));
-  base::win::RegKey reg_key;
-  GetEventsRegKey(kEventsSubkeyName, &product, KEY_WRITE, &reg_key);
-  if (reg_key.WriteValue(event_rlz_wide.c_str(), 1) != ERROR_SUCCESS) {
-    ASSERT_STRING("AddProductEvent: Could not write the new event value");
-    return false;
-  }
-
-  return true;
-}
-
-bool RlzValueStoreRegistry::ReadProductEvents(Product product,
-                                             std::vector<std::string>* events) {
-  // Open the events key.
-  base::win::RegKey events_key;
-  GetEventsRegKey(kEventsSubkeyName, &product, KEY_READ, &events_key);
-  if (!events_key.Valid())
-    return false;
-
-  // Append the events to the buffer.
-  int num_values = 0;
-  LONG result = ERROR_SUCCESS;
-  for (num_values = 0; result == ERROR_SUCCESS; ++num_values) {
-    // Max 32767 bytes according to MSDN, but we never use that much.
-    const size_t kMaxValueNameLength = 2048;
-    char buffer[kMaxValueNameLength];
-    DWORD size = arraysize(buffer);
-
-    result = RegEnumValueA(events_key.Handle(), num_values, buffer, &size,
-                           NULL, NULL, NULL, NULL);
-    if (result == ERROR_SUCCESS)
-      events->push_back(std::string(buffer));
-  }
-
-  return result == ERROR_NO_MORE_ITEMS;
-}
-
-bool RlzValueStoreRegistry::ClearProductEvent(Product product,
-                                              const char* event_rlz) {
-  std::wstring event_rlz_wide(ASCIIToWide(event_rlz));
-  base::win::RegKey key;
-  GetEventsRegKey(kEventsSubkeyName, &product, KEY_WRITE, &key);
-  key.DeleteValue(event_rlz_wide.c_str());
-
-  // Verify deletion.
-  DWORD value;
-  if (key.ReadValueDW(event_rlz_wide.c_str(), &value) == ERROR_SUCCESS) {
-    ASSERT_STRING("ClearProductEvent: Could not delete the event value.");
-    return false;
-  }
-
-  return true;
-}
-
-bool RlzValueStoreRegistry::ClearAllProductEvents(Product product) {
-  return ClearAllProductEventValues(product, kEventsSubkeyName);
-}
-
-bool RlzValueStoreRegistry::AddStatefulEvent(Product product,
-                                             const char* event_rlz) {
-  base::win::RegKey key;
-  std::wstring event_rlz_wide(ASCIIToWide(event_rlz));
-  if (!GetEventsRegKey(kStatefulEventsSubkeyName, &product, KEY_WRITE, &key) ||
-      key.WriteValue(event_rlz_wide.c_str(), 1) != ERROR_SUCCESS) {
-    ASSERT_STRING(
-        "AddStatefulEvent: Could not write the new stateful event");
-    return false;
-  }
-
-  return true;
-}
-
-bool RlzValueStoreRegistry::IsStatefulEvent(Product product,
-                                            const char* event_rlz) {
-  DWORD value;
-  base::win::RegKey key;
-  GetEventsRegKey(kStatefulEventsSubkeyName, &product, KEY_READ, &key);
-  std::wstring event_rlz_wide(ASCIIToWide(event_rlz));
-  return key.ReadValueDW(event_rlz_wide.c_str(), &value) == ERROR_SUCCESS;
-}
-
-bool RlzValueStoreRegistry::ClearAllStatefulEvents(Product product) {
-  return ClearAllProductEventValues(product, kStatefulEventsSubkeyName);
-}
-
-void RlzValueStoreRegistry::CollectGarbage() {
-  // Delete each of the known subkeys if empty.
-  const char* subkeys[] = {
-    kRlzsSubkeyName,
-    kEventsSubkeyName,
-    kStatefulEventsSubkeyName,
-    kPingTimesSubkeyName
-  };
-
-  for (int i = 0; i < arraysize(subkeys); i++) {
-    std::string subkey_name;
-    base::StringAppendF(&subkey_name, "%s\\%s", kLibKeyName, subkeys[i]);
-    AppendBrandToString(&subkey_name);
-
-    VERIFY(DeleteKeyIfEmpty(HKEY_CURRENT_USER,
-                            ASCIIToWide(subkey_name).c_str()));
-  }
-
-  // Delete the library key and its parents too now if empty.
-  VERIFY(DeleteKeyIfEmpty(HKEY_CURRENT_USER, GetWideLibKeyName().c_str()));
-  VERIFY(DeleteKeyIfEmpty(HKEY_CURRENT_USER, kGoogleCommonKeyName));
-  VERIFY(DeleteKeyIfEmpty(HKEY_CURRENT_USER, kGoogleKeyName));
-}
-
-ScopedRlzValueStoreLock::ScopedRlzValueStoreLock() {
-  if (!lock_.failed())
-    store_.reset(new RlzValueStoreRegistry);
+  rlz_store_->MarkNeedsEmptyValue(list_name);
+  size_t index;
+  if (list->Remove(value, &index))
+    rlz_store_->ReportValueChanged(list_name);
+  return true;
+}
+
+
+ScopedRlzValueStoreLock::ScopedRlzValueStoreLock()
+    : store_(RlzValueStoreChromeOS::GetInstance()) {
+  DCHECK(store_->CalledOnValidThread());
 }
 
 ScopedRlzValueStoreLock::~ScopedRlzValueStoreLock() {
 }
 
 RlzValueStore* ScopedRlzValueStoreLock::GetStore() {
-  return store_.get();
-}
+  return store_;
+}
+
+namespace testing {
+
+void SetRlzStoreDirectory(const FilePath& directory) {
+  g_testing_rlz_store_path_ = directory;
+}
+
+}  // namespace testing
 
 }  // namespace rlz_lib