Split the aggregate dictionary of content settings exceptions into per-type dictionaries

components/content_settings/core/browser/content_settings_pref_provider.cc

Index: components/content_settings/core/browser/content_settings_pref_provider.cc
diff --git a/components/content_settings/core/browser/content_settings_pref_provider.cc b/components/content_settings/core/browser/content_settings_pref_provider.cc
index 6c855d3e2ff94fe6482e74449017add60ec36ff9..d02eb4ff173d6fc4afcfff5c6f9af1e9a1ba9846 100644
--- a/components/content_settings/core/browser/content_settings_pref_provider.cc
+++ b/components/content_settings/core/browser/content_settings_pref_provider.cc
@@ -8,10 +8,12 @@
 #include <string>
 #include <utility>
 
+#include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
 #include "base/prefs/pref_service.h"
+#include "base/prefs/scoped_user_pref_update.h"
 #include "base/strings/string_split.h"
 #include "base/time/clock.h"
 #include "base/time/default_clock.h"
@@ -26,9 +28,68 @@
 
 namespace {
 
+//typedef std::pair<std::string, std::string> StringPair;
+
+const char kPerPluginPrefName[] = "per_plugin";
+
+// If the given content type supports resource identifiers in user preferences,
+// returns true and sets |pref_key| to the key in the content settings
+// dictionary under which per-resource content settings are stored.
+// Otherwise, returns false.
+bool GetResourceTypeName(ContentSettingsType content_type,
+                         std::string* pref_key) {
+  if (content_type == CONTENT_SETTINGS_TYPE_PLUGINS) {
+    *pref_key = kPerPluginPrefName;
+    return true;
+  }
+  return false;
+}
+
+ContentSetting FixObsoleteCookiePromptMode(ContentSettingsType content_type,
+                                           ContentSetting setting) {
+  if (content_type == CONTENT_SETTINGS_TYPE_COOKIES &&
+      setting == CONTENT_SETTING_ASK) {
+    return CONTENT_SETTING_BLOCK;
+  }
+  return setting;
+}
+
 const char kAudioKey[] = "audio";
 const char kVideoKey[] = "video";
 
+const char* kContentSettingsExceptionsPrefs[] = {
+    prefs::kContentSettingsCookiesPatternPairs,
+    prefs::kContentSettingsImagesPatternPairs,
+    prefs::kContentSettingsJavaScriptPatternPairs,
+    prefs::kContentSettingsPluginsPatternPairs,
+    prefs::kContentSettingsPopupsPatternPairs,
+    prefs::kContentSettingsGeolocationPatternPairs,
+    prefs::kContentSettingsNotificationsPatternPairs,
+    prefs::kContentSettingsAutoSelectCertificatePatternPairs,
+    prefs::kContentSettingsFullScreenPatternPairs,
+    prefs::kContentSettingsMouseLockPatternPairs,
+    prefs::kContentSettingsMixedScriptPatternPairs,
+    prefs::kContentSettingsMediaStreamPatternPairs,
+    prefs::kContentSettingsMediaStreamMicPatternPairs,
+    prefs::kContentSettingsMediaStreamCameraPatternPairs,
+    prefs::kContentSettingsProtocolHandlersPatternPairs,
+    prefs::kContentSettingsPpapiBrokerPatternPairs,
+    prefs::kContentSettingsAutomaticDownloadsPatternPairs,
+    prefs::kContentSettingsMidiSysexPatternPairs,
+    prefs::kContentSettingsPushMessagingPatternPairs,
+    prefs::kContentSettingsSSLCertDecisionsPatternPairs,
+#if defined(OS_WIN)
+    prefs::kContentSettingsMetroSwitchToDesktopPatternPairs,
+#elif defined(OS_ANDROID) || defined(OS_CHROMEOS)
+    prefs::kContentSettingsProtectedMediaIdentifierPatternPairs,
+#endif
+    prefs::kContentSettingsAppBannerPatternPairs
+};
+static_assert(arraysize(kContentSettingsExceptionsPrefs)
+              == CONTENT_SETTINGS_NUM_TYPES,
+              "kContentSettingsExceptionsPrefs should have "
+              "CONTENT_SETTINGS_NUM_TYPES elements");
+
 }  // namespace
 
 namespace content_settings {
@@ -47,11 +108,24 @@ void PrefProvider::RegisterProfilePrefs(
   registry->RegisterDictionaryPref(
       prefs::kContentSettingsPatternPairs,
       user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  registry->RegisterBooleanPref(
+      prefs::kContentSettingsPatternPairsMigrated,
+      false,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+
+  for (size_t i = 0; i < CONTENT_SETTINGS_NUM_TYPES; ++i)
+    registry->RegisterDictionaryPref(
+        kContentSettingsExceptionsPrefs[i],
+        IsContentSettingsTypeSyncable(ContentSettingsType(i))
+            ? user_prefs::PrefRegistrySyncable::SYNCABLE_PREF
+            : user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF
+    );
 }
 
 PrefProvider::PrefProvider(PrefService* prefs, bool incognito)
     : prefs_(prefs),
-      clock_(new base::DefaultClock()) {
+      clock_(new base::DefaultClock()),
+      updating_old_preferences_(false) {
   DCHECK(prefs_);
   // Verify preferences version.
   if (!prefs_->HasPrefPath(prefs::kContentSettingsVersion)) {
@@ -64,18 +138,39 @@ PrefProvider::PrefProvider(PrefService* prefs, bool incognito)
   }
 
   pref_change_registrar_.Init(prefs_);
-  content_settings_pref_.reset(new ContentSettingsPref(
-      prefs_, &pref_change_registrar_, clock_.get(), incognito,
-      base::Bind(&PrefProvider::Notify,
-                 base::Unretained(this))));
+
+  pref_change_registrar_.Add(prefs::kContentSettingsPatternPairs, base::Bind(
+      &PrefProvider::OnOldContentSettingsPatternPairsChanged,
+      base::Unretained(this)));
+
+  content_settings_prefs_.resize(CONTENT_SETTINGS_NUM_TYPES);
+  for (size_t i = 0; i < CONTENT_SETTINGS_NUM_TYPES; ++i) {
+    content_settings_prefs_[i].reset(new ContentSettingsPref(
+        ContentSettingsType(i), prefs_, &pref_change_registrar_,
+        kContentSettingsExceptionsPrefs[i], incognito,
+        &updating_old_preferences_, base::Bind(&PrefProvider::Notify,
+                                               base::Unretained(this))));
+  }
+
+  ReadContentSettingsFromOldPref();
 
   if (!incognito) {
+    size_t num_exceptions = 0;
+    for (size_t i = 0; i < CONTENT_SETTINGS_NUM_TYPES; ++i)
+      num_exceptions += content_settings_prefs_[i]->GetNumExceptions();
+
     UMA_HISTOGRAM_COUNTS("ContentSettings.NumberOfExceptions",
-                         content_settings_pref_->GetNumExceptions());
+                         num_exceptions);
+
+    // Migrate all the exceptions from the aggregate dictionary preference
+    // to the separate dictionaries.
+    MigrateAllExceptions();
+
     // Migrate the obsolete media content setting exceptions to the new
-    // settings. This needs to be done after ReadContentSettingsFromPref().
+    // settings.
     MigrateObsoleteMediaContentSetting();
   }
+
 }
 
 PrefProvider::~PrefProvider() {
@@ -86,9 +181,9 @@ RuleIterator* PrefProvider::GetRuleIterator(
     ContentSettingsType content_type,
     const ResourceIdentifier& resource_identifier,
     bool incognito) const {
-  return content_settings_pref_->GetRuleIterator(content_type,
-                                                 resource_identifier,
-                                                 incognito);
+  return content_settings_prefs_[content_type]->GetRuleIterator(
+                                                    resource_identifier,
+                                                    incognito);
 }
 
 bool PrefProvider::SetWebsiteSetting(
@@ -100,11 +195,22 @@ bool PrefProvider::SetWebsiteSetting(
   DCHECK(CalledOnValidThread());
   DCHECK(prefs_);
 
-  return content_settings_pref_->SetWebsiteSetting(primary_pattern,
-                                                   secondary_pattern,
-                                                   content_type,
-                                                   resource_identifier,
-                                                   in_value);
+  // Default settings are set using a wildcard pattern for both
+  // |primary_pattern| and |secondary_pattern|. Don't store default settings in
+  // the |PrefProvider|. The |PrefProvider| handles settings for specific
+  // sites/origins defined by the |primary_pattern| and the |secondary_pattern|.
+  // Default settings are handled by the |DefaultProvider|.
+  if (primary_pattern == ContentSettingsPattern::Wildcard() &&
+      secondary_pattern == ContentSettingsPattern::Wildcard() &&
+      resource_identifier.empty()) {
+    return false;
+  }
+
+  return content_settings_prefs_[content_type]->SetWebsiteSetting(
+                                                    primary_pattern,
+                                                    secondary_pattern,
+                                                    resource_identifier,
+                                                    in_value);
 }
 
 void PrefProvider::ClearAllContentSettingsRules(
@@ -112,7 +218,7 @@ void PrefProvider::ClearAllContentSettingsRules(
   DCHECK(CalledOnValidThread());
   DCHECK(prefs_);
 
-  content_settings_pref_->ClearAllContentSettingsRules(content_type);
+  content_settings_prefs_[content_type]->ClearAllContentSettingsRules();
 }
 
 void PrefProvider::ShutdownOnUIThread() {
@@ -127,18 +233,17 @@ void PrefProvider::UpdateLastUsage(
     const ContentSettingsPattern& primary_pattern,
     const ContentSettingsPattern& secondary_pattern,
     ContentSettingsType content_type) {
-  content_settings_pref_->UpdateLastUsage(primary_pattern,
-                                          secondary_pattern,
-                                          content_type);
+  content_settings_prefs_[content_type]->UpdateLastUsage(primary_pattern,
+                                                         secondary_pattern,
+                                                         clock_.get());
 }
 
 base::Time PrefProvider::GetLastUsage(
     const ContentSettingsPattern& primary_pattern,
     const ContentSettingsPattern& secondary_pattern,
     ContentSettingsType content_type) {
-  return content_settings_pref_->GetLastUsage(primary_pattern,
-                                              secondary_pattern,
-                                              content_type);
+  return content_settings_prefs_[content_type]->GetLastUsage(primary_pattern,
+                                                             secondary_pattern);
 }
 
 // ////////////////////////////////////////////////////////////////////////////
@@ -205,9 +310,174 @@ void PrefProvider::Notify(
                   resource_identifier);
 }
 
+void PrefProvider::ReadContentSettingsFromOldPref() {
+  // |DictionaryPrefUpdate| sends out notifications when destructed. This
+  // construction order ensures |AutoLock| gets destroyed first and |old_lock_|
+  // is not held when the notifications are sent. Also, |auto_reset| must be
+  // still valid when the notifications are sent, so that |Observe| skips the
+  // notification.
+  base::AutoReset<bool> auto_reset(&updating_old_preferences_, true);
+  DictionaryPrefUpdate update(prefs_, prefs::kContentSettingsPatternPairs);
+
+  const base::DictionaryValue* all_settings_dictionary =
+      prefs_->GetDictionary(prefs::kContentSettingsPatternPairs);
+
+  old_value_map_.clear();
+
+  // Careful: The returned value could be NULL if the pref has never been set.
+  if (!all_settings_dictionary)
+    return;
+
+  base::DictionaryValue* mutable_settings;
+  scoped_ptr<base::DictionaryValue> mutable_settings_scope;
+
+  if (!is_incognito_) {
+    mutable_settings = update.Get();
+  } else {
+    // Create copy as we do not want to persist anything in OTR prefs.
+    mutable_settings = all_settings_dictionary->DeepCopy();
+    mutable_settings_scope.reset(mutable_settings);
+  }
+  // Convert all Unicode patterns into punycode form, then read.
+  ContentSettingsPref::CanonicalizeContentSettingsExceptions(mutable_settings);
+
+  for (base::DictionaryValue::Iterator i(*mutable_settings); !i.IsAtEnd();
+       i.Advance()) {
+    const std::string& pattern_str(i.key());
+    std::pair<ContentSettingsPattern, ContentSettingsPattern> pattern_pair =
+        ParsePatternString(pattern_str);
+    if (!pattern_pair.first.IsValid() ||
+        !pattern_pair.second.IsValid()) {
+      // TODO: Change this to DFATAL when crbug.com/132659 is fixed.
+      LOG(ERROR) << "Invalid pattern strings: " << pattern_str;
+      continue;
+    }
+
+    // Get settings dictionary for the current pattern string, and read
+    // settings from the dictionary.
+    const base::DictionaryValue* settings_dictionary = NULL;
+    bool is_dictionary = i.value().GetAsDictionary(&settings_dictionary);
+    DCHECK(is_dictionary);
+
+    for (size_t i = 0; i < CONTENT_SETTINGS_NUM_TYPES; ++i) {
+      ContentSettingsType content_type = static_cast<ContentSettingsType>(i);
+
+      std::string res_dictionary_path;
+      if (GetResourceTypeName(content_type, &res_dictionary_path)) {
+        const base::DictionaryValue* resource_dictionary = NULL;
+        if (settings_dictionary->GetDictionary(
+                res_dictionary_path, &resource_dictionary)) {
+          for (base::DictionaryValue::Iterator j(*resource_dictionary);
+               !j.IsAtEnd();
+               j.Advance()) {
+            const std::string& resource_identifier(j.key());
+            int setting = CONTENT_SETTING_DEFAULT;
+            bool is_integer = j.value().GetAsInteger(&setting);
+            DCHECK(is_integer);
+            DCHECK_NE(CONTENT_SETTING_DEFAULT, setting);
+            old_value_map_[content_type].push_back(
+                (ContentSettingsPrefEntry){
+                    pattern_pair.first,
+                    pattern_pair.second,
+                    resource_identifier,
+                    make_scoped_ptr(new base::FundamentalValue(setting))});
+          }
+        }
+      }
+      base::Value* value = NULL;
+      if (HostContentSettingsMap::ContentTypeHasCompoundValue(content_type)) {
+        const base::DictionaryValue* setting = NULL;
+        // TODO(xians): Handle the non-dictionary types.
+        if (settings_dictionary->GetDictionaryWithoutPathExpansion(
+            GetTypeName(ContentSettingsType(i)), &setting)) {
+          DCHECK(!setting->empty());
+          value = setting->DeepCopy();
+        }
+      } else {
+        int setting = CONTENT_SETTING_DEFAULT;
+        if (settings_dictionary->GetIntegerWithoutPathExpansion(
+                GetTypeName(ContentSettingsType(i)), &setting)) {
+          DCHECK_NE(CONTENT_SETTING_DEFAULT, setting);
+          setting = FixObsoleteCookiePromptMode(content_type,
+                                                ContentSetting(setting));
+          value = new base::FundamentalValue(setting);
+        }
+      }
+
+      // |old_value_map_| will take the ownership of |value|.
+      if (value != NULL) {
+        old_value_map_[content_type].push_back(
+            (ContentSettingsPrefEntry){
+                pattern_pair.first,
+                pattern_pair.second,
+                ResourceIdentifier(),
+                make_scoped_ptr(value)});
+      }
+    }
+  }
+}
+
+void PrefProvider::WriteSettingsToNewPreferences(bool syncable_only) {
+  if (updating_old_preferences_)
+    return;
+
+  base::AutoReset<bool> auto_reset(&updating_old_preferences_, true);
+
+  ReadContentSettingsFromOldPref();
+
+  for (ContentSettingsPrefEntryMap::iterator it = old_value_map_.begin();
+       it != old_value_map_.end(); ++it) {
+    ContentSettingsType content_type = it->first;
+    if (syncable_only && !IsContentSettingsTypeSyncable(content_type))
+      return;
+
+    std::vector<ContentSettingsPrefEntry>& entries = it->second;
+
+    content_settings_prefs_[content_type]->ClearAllContentSettingsRules();
+
+    for (size_t i = 0; i < entries.size(); ++i) {

[msramek, 2015/03/24 15:11:45]

This for-cycle migrates exceptions one by one. Unless PrefService caches files,
this means a disk access for every exception, which might be very slow if you
have a lot of them.

It works as it is, but I think we should migrate the exceptions in bulk, by
reading the old dictionary, processing it in memory and then writing whole
dictionaries back to the pref file.

[msramek, 2015/03/25 11:58:50]

I tried this out with 1000 exceptions and the migration is pretty fast; I guess
PrefService does cache the preferences. Then again, the whole "Manage
exceptions" dialog is pretty slow, even before this change was applied.

+      content_settings_prefs_[content_type]->SetWebsiteSetting(
+          entries[i].primary_pattern,
+          entries[i].secondary_pattern,
+          entries[i].resource_identifier,
+          entries[i].value->DeepCopy());
+    }
+  }
+
+  old_value_map_.clear();
+}
+
+void PrefProvider::OnOldContentSettingsPatternPairsChanged() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  WriteSettingsToNewPreferences(true);
+}
+
+void PrefProvider::MigrateAllExceptions() {
+  if (prefs_->GetBoolean(prefs::kContentSettingsPatternPairsMigrated))
+    return;
+  WriteSettingsToNewPreferences(false);
+
+  // Protected media identifier settings should be reset during the migration.
+#if defined(OS_ANDROID) || defined(OS_CHROMEOS)
+  content_settings_prefs_[CONTENT_SETTINGS_TYPE_PROTECTED_MEDIA_IDENTIFIER]->
+      ClearAllContentSettingsRules();
+#endif
+
+  prefs_->SetBoolean(prefs::kContentSettingsPatternPairsMigrated, true);
+}
+
 void PrefProvider::SetClockForTesting(scoped_ptr<base::Clock> clock) {
   clock_ = clock.Pass();
-  content_settings_pref_->SetClockForTesting(clock_.get());
+}
+
+bool PrefProvider::TestAllLocks() const {
+  for (size_t i = 0; i < CONTENT_SETTINGS_NUM_TYPES; ++i) {
+    if (!content_settings_prefs_[i]->lock_.Try())
+      return false;
+    content_settings_prefs_[i]->lock_.Release();
+  }
+  return true;
 }
 
 }  // namespace content_settings