Introduce incognito preference settings.

chrome/browser/prefs/pref_service.cc

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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 "chrome/browser/prefs/pref_service.h"
 
 #include <algorithm>
 #include <string>
 
 #include "app/l10n_util.h"
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/stl_util-inl.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
 #include "base/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_thread.h"
+#include "chrome/browser/extensions/extension_pref_store.h"
 #include "chrome/browser/policy/configuration_policy_pref_store.h"
 #include "chrome/browser/prefs/command_line_pref_store.h"
 #include "chrome/browser/prefs/default_pref_store.h"
+#include "chrome/browser/prefs/overlay_persistent_pref_store.h"
 #include "chrome/browser/prefs/pref_notifier_impl.h"
 #include "chrome/browser/prefs/pref_value_store.h"
 #include "chrome/common/json_pref_store.h"
 #include "chrome/common/notification_service.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 
 namespace {
 
 // A helper function for RegisterLocalized*Pref that creates a Value* based on
@@ skipping 70 matching lines @@
   ConfigurationPolicyPrefStore* device_management =
       ConfigurationPolicyPrefStore::CreateDeviceManagementPolicyPrefStore(
           profile);
   CommandLinePrefStore* command_line =
       new CommandLinePrefStore(CommandLine::ForCurrentProcess());
   JsonPrefStore* user = new JsonPrefStore(
       pref_filename,
       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE));
   ConfigurationPolicyPrefStore* recommended =
       ConfigurationPolicyPrefStore::CreateRecommendedPolicyPrefStore();
+  DefaultPrefStore* default_pref_store = new DefaultPrefStore();
 
   return new PrefService(managed, device_management, extension_prefs,
-                         command_line, user, recommended);
+                         command_line, user, recommended, default_pref_store,
+                         true);
+}
+
+PrefService* PrefService::CreateIncognitoPrefService(
+    PrefStore* incognito_extension_prefs) {
+  return new PrefService(
+      managed_platform_prefs_,
+      device_management_prefs_,
+      incognito_extension_prefs,
+      command_line_prefs_,
+      new OverlayPersistentPrefStore(user_pref_store_.get()),
+      recommended_prefs_,
+      default_store_,
+      false
+  );
 }
 
 PrefService::PrefService(PrefStore* managed_platform_prefs,
                          PrefStore* device_management_prefs,
                          PrefStore* extension_prefs,
                          PrefStore* command_line_prefs,
                          PersistentPrefStore* user_prefs,
-                         PrefStore* recommended_prefs)
-    : user_pref_store_(user_prefs) {
+                         PrefStore* recommended_prefs,
+                         DefaultPrefStore* default_store,
+                         bool init_from_storage)
+    : managed_platform_prefs_(managed_platform_prefs),
+      device_management_prefs_(device_management_prefs),
+      extension_prefs_(extension_prefs),
+      command_line_prefs_(command_line_prefs),
+      recommended_prefs_(recommended_prefs),
+      user_pref_store_(user_prefs),
+      default_store_(default_store) {
   pref_notifier_.reset(new PrefNotifierImpl(this));
-  default_store_ = new DefaultPrefStore();
   pref_value_store_ =
-      new PrefValueStore(managed_platform_prefs,
-                         device_management_prefs,
-                         extension_prefs,
-                         command_line_prefs,
+      new PrefValueStore(managed_platform_prefs_,
+                         device_management_prefs_,
+                         extension_prefs_,
+                         command_line_prefs_,
                          user_pref_store_,
-                         recommended_prefs,
+                         recommended_prefs_,
                          default_store_,
                          pref_notifier_.get());
-  InitFromStorage();
+  if (init_from_storage)

[Mattias Nissler (ping if slow), 2011/01/05 12:08:07]

I believe I have commented on this before but don't remember the conclusion:
Can't we just drop the init_from_storage parameter and call InitFromStorage()
unconditionally?

[battre, 2011/01/05 20:23:08]

Done.

+    InitFromStorage();
 }
 
 PrefService::~PrefService() {
   DCHECK(CalledOnValidThread());
   STLDeleteContainerPointers(prefs_.begin(), prefs_.end());
   prefs_.clear();
 }
 
 void PrefService::InitFromStorage() {
   const PersistentPrefStore::PrefReadError error =
@@ skipping 167 matching lines @@
   bool rv = pref->GetValue()->GetAsString(&result);
   DCHECK(rv);
 #if defined(OS_POSIX)
   // We store filepaths as UTF8, so convert it back to the system type.
   result = base::SysWideToNativeMB(UTF8ToWide(result));
 #endif
   return FilePath(result);
 }
 
 bool PrefService::HasPrefPath(const char* path) const {
-  return pref_value_store_->HasPrefPath(path);
+  const Preference* pref = FindPreference(path);
+  return pref && !pref->IsDefaultValue();
 }
 
 const PrefService::Preference* PrefService::FindPreference(
     const char* pref_name) const {
   DCHECK(CalledOnValidThread());
-  Preference p(this, pref_name);
+  Preference p(this, pref_name, Value::TYPE_NULL);
   PreferenceSet::const_iterator it = prefs_.find(&p);
-  return it == prefs_.end() ? NULL : *it;
+  if (it != prefs_.end())
+    return *it;
+  const Value::ValueType type = default_store_->GetType(pref_name);
+  if (type == Value::TYPE_NULL)
+    return NULL;
+  Preference* new_pref = new Preference(this, pref_name, type);
+  prefs_.insert(new_pref);
+  return new_pref;
 }
 
 bool PrefService::ReadOnly() const {
   return user_pref_store_->ReadOnly();
 }
 
 PrefNotifier* PrefService::pref_notifier() const {
   return pref_notifier_.get();
 }
 
 bool PrefService::IsManagedPreference(const char* pref_name) const {
   const Preference* pref = FindPreference(pref_name);
-  if (pref && pref->IsManaged()) {
-    return true;
-  }
-  return false;
+  return pref && pref->IsManaged();
 }
 
 const DictionaryValue* PrefService::GetDictionary(const char* path) const {
   DCHECK(CalledOnValidThread());
 
   const Preference* pref = FindPreference(path);
   if (!pref) {
     NOTREACHED() << "Trying to read an unregistered pref: " << path;
     return NULL;
   }
@@ skipping 35 matching lines @@
 
   if (FindPreference(path)) {
     NOTREACHED() << "Tried to register duplicate pref " << path;
     return;
   }
 
   Value::ValueType orig_type = default_value->GetType();
   DCHECK(orig_type != Value::TYPE_NULL && orig_type != Value::TYPE_BINARY) <<
          "invalid preference type: " << orig_type;
 
-  // We set the default value of dictionaries and lists to be null so it's
-  // easier for callers to check for empty dict/list prefs. The PrefValueStore
-  // accepts ownership of the value (null or default_value).
-  if (Value::TYPE_LIST == orig_type || Value::TYPE_DICTIONARY == orig_type) {
-    default_store_->SetDefaultValue(path, Value::CreateNullValue());
-  } else {
-    // Hand off ownership.
-    default_store_->SetDefaultValue(path, scoped_value.release());
-  }
+  // Hand off ownership.
+  default_store_->SetDefaultValue(path, scoped_value.release());
 
-  pref_value_store_->RegisterPreferenceType(path, orig_type);
-  prefs_.insert(new Preference(this, path));
+  prefs_.insert(new Preference(this, path, orig_type));

[Mattias Nissler (ping if slow), 2011/01/05 12:08:07]

If new do this, we don't need the lazy creation code at line 365 above, no?

[battre, 2011/01/05 20:23:08]

Done.

 }
 
 void PrefService::ClearPref(const char* path) {
   DCHECK(CalledOnValidThread());
 
   const Preference* pref = FindPreference(path);
   if (!pref) {
     NOTREACHED() << "Trying to clear an unregistered pref: " << path;
     return;
   }
   user_pref_store_->RemoveValue(path);
 }
 
 void PrefService::Set(const char* path, const Value& value) {
   DCHECK(CalledOnValidThread());
 
   const Preference* pref = FindPreference(path);
   if (!pref) {
     NOTREACHED() << "Trying to write an unregistered pref: " << path;
     return;
   }
 
-  // Allow dictionary and list types to be set to null, which removes their
-  // user values.
-  if (value.GetType() == Value::TYPE_NULL &&
-      (pref->GetType() == Value::TYPE_DICTIONARY ||
-       pref->GetType() == Value::TYPE_LIST)) {
-    user_pref_store_->RemoveValue(path);
-  } else if (pref->GetType() != value.GetType()) {
+  if (pref->GetType() != value.GetType()) {
     NOTREACHED() << "Trying to set pref " << path
                  << " of type " << pref->GetType()
                  << " to value of type " << value.GetType();
   } else {
     user_pref_store_->SetValue(path, value.DeepCopy());
   }
 }
 
 void PrefService::SetBoolean(const char* path, bool value) {
   SetUserPrefValue(path, Value::CreateBooleanValue(value));
@@ skipping 121 matching lines @@
     return;
   }
 
   user_pref_store_->SetValue(path, new_value);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // PrefService::Preference
 
 PrefService::Preference::Preference(const PrefService* service,
-                                    const char* name)
+                                    const char* name,
+                                    Value::ValueType type)
       : name_(name),
+        type_(type),
         pref_service_(service) {
   DCHECK(name);
   DCHECK(service);
 }
 
 Value::ValueType PrefService::Preference::GetType() const {
-  return pref_service_->pref_value_store_->GetRegisteredType(name_);
+  return type_;
 }
 
 const Value* PrefService::Preference::GetValue() const {
   DCHECK(pref_service_->FindPreference(name_.c_str())) <<
       "Must register pref before getting its value";
 
   Value* found_value = NULL;
-  if (pref_service_->pref_value_store_->GetValue(name_, &found_value))
+  if (pref_service_->pref_value_store_->GetValue(name_, type_, &found_value)) {
+    DCHECK(found_value->IsType(type_));
     return found_value;
+  }
 
   // Every registered preference has at least a default value.
   NOTREACHED() << "no valid value found for registered pref " << name_;
   return NULL;
 }
 
 bool PrefService::Preference::IsManaged() const {
   PrefValueStore* pref_value_store = pref_service_->pref_value_store_;
   return pref_value_store->PrefValueInManagedPlatformStore(name_.c_str()) ||
       pref_value_store->PrefValueInDeviceManagementStore(name_.c_str());
@@ skipping 21 matching lines @@
 
 bool PrefService::Preference::IsDefaultValue() const {
   return pref_service_->pref_value_store_->
       PrefValueFromDefaultStore(name_.c_str());
 }
 
 bool PrefService::Preference::IsUserModifiable() const {
   return pref_service_->pref_value_store_->
       PrefValueUserModifiable(name_.c_str());
 }