chrome/browser/ui/zoom/chrome_zoom_level_prefs.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 "chrome/browser/ui/zoom/chrome_zoom_level_prefs.h"
   6
   7 #include <sstream>
   8
   9 #include "base/bind.h"
  10 #include "base/prefs/json_pref_store.h"
  11 #include "base/prefs/pref_filter.h"
  12 #include "base/prefs/pref_registry_simple.h"
  13 #include "base/prefs/pref_service_factory.h"
  14 #include "base/prefs/scoped_user_pref_update.h"
  15 #include "base/strings/string_number_conversions.h"
  16 #include "base/values.h"
  17 #include "chrome/common/chrome_constants.h"
  18 #include "chrome/common/pref_names.h"
  19 #include "content/public/browser/browser_thread.h"
  20 #include "content/public/browser/host_zoom_map.h"
  21 #include "content/public/common/page_zoom.h"
  22
  23 namespace {
  24
  25 std::string GetHash(
  26     const base::FilePath& relative_path) {
  27   size_t int_key =
  28 #if defined(COMPILER_MSVC)
  29       BASE_HASH_NAMESPACE::hash_value(relative_path);
  30 #else
  31       BASE_HASH_NAMESPACE::hash<base::FilePath>()(relative_path);
  32 #endif  // COMPILER
  33   return base::SizeTToString(int_key);
  34 }
  35
  36 }  // namespace
  37
  38 namespace chrome {
  39
  40 ChromeZoomLevelPrefs::ChromeZoomLevelPrefs(PrefService* pref_service,
  41                                            const base::FilePath& profile_path)
  42     : pref_service_(pref_service),
  43       profile_path_(profile_path),
  44       host_zoom_map_(nullptr) {
  45   DCHECK(pref_service_);
  46 }
  47
  48 ChromeZoomLevelPrefs::~ChromeZoomLevelPrefs() {
  49 }
  50
  51 void ChromeZoomLevelPrefs::InitPrefsAndCopyToHostZoomMap(
  52     const base::FilePath& partition_path,
  53     content::HostZoomMap* host_zoom_map) {
  54   DCHECK(!partition_path.empty());
  55   DCHECK((partition_path == profile_path_) ||
  56          profile_path_.IsParent(partition_path));
  57   // This init function must be called only once.
  58   DCHECK(!host_zoom_map_);
  59   DCHECK(host_zoom_map);
  60   host_zoom_map_ = host_zoom_map;
  61
  62   // Create a partition_key string with no '.'s in it. For the default
  63   // StoragePartition, this string will always be "0".
  64   base::FilePath partition_relative_path;
  65   profile_path_.AppendRelativePath(partition_path, &partition_relative_path);
  66   partition_key_ = GetHash(partition_relative_path);
  67
  68   // Initialize the default zoom level.
  69   host_zoom_map_->SetDefaultZoomLevel(GetDefaultZoomLevelPref());
  70
  71   // Initialize the HostZoomMap with per-host zoom levels from the persisted
  72   // zoom-level preference values.
  73   const base::DictionaryValue* host_zoom_dictionaries =
  74       pref_service_->GetDictionary(prefs::kPartitionPerHostZoomLevels);
  75   const base::DictionaryValue* host_zoom_dictionary = nullptr;
  76   if (host_zoom_dictionaries->GetDictionary(partition_key_,
  77                                             &host_zoom_dictionary)) {
  78     // Since we're calling this before setting up zoom_subscription_ below we
  79     // don't need to worry that host_zoom_dictionary is indirectly affected
  80     // by calls to HostZoomMap::SetZoomLevelForHost().
  81     ExtractPerHostZoomLevels(host_zoom_dictionary);
  82   }
  83   zoom_subscription_ = host_zoom_map_->AddZoomLevelChangedCallback(base::Bind(
  84       &ChromeZoomLevelPrefs::OnZoomLevelChanged, base::Unretained(this)));
  85 }
  86
  87 std::string ChromeZoomLevelPrefs::GetHashForTesting(
  88     const base::FilePath& relative_path) {
  89   return GetHash(relative_path);
  90 }
  91
  92 void ChromeZoomLevelPrefs::SetDefaultZoomLevelPref(double level) {
  93   if (content::ZoomValuesEqual(level, host_zoom_map_->GetDefaultZoomLevel()))
  94     return;
  95
  96   DictionaryPrefUpdate update(pref_service_, prefs::kPartitionDefaultZoomLevel);
  97   update->SetDouble(partition_key_, level);
  98   // For unregistered paths, OnDefaultZoomLevelChanged won't be called, so
  99   // set this manually.
 100   host_zoom_map_->SetDefaultZoomLevel(level);
 101   default_zoom_changed_callbacks_.Notify();
 102 }
 103
 104 double ChromeZoomLevelPrefs::GetDefaultZoomLevelPref() const {
 105   double default_zoom_level = 0.0;
 106
 107   const base::DictionaryValue* default_zoom_level_dictionary =
 108       pref_service_->GetDictionary(prefs::kPartitionDefaultZoomLevel);
 109   // If no default has been previously set, the default returned is the
 110   // value used to initialize default_zoom_level in this function.
 111   default_zoom_level_dictionary->GetDouble(partition_key_, &default_zoom_level);
 112   return default_zoom_level;
 113 }
 114
 115 scoped_ptr<ChromeZoomLevelPrefs::DefaultZoomLevelSubscription>
 116 ChromeZoomLevelPrefs::RegisterDefaultZoomLevelCallback(
 117     const base::Closure& callback) {
 118   return default_zoom_changed_callbacks_.Add(callback);
 119 }
 120
 121 void ChromeZoomLevelPrefs::OnZoomLevelChanged(
 122     const content::HostZoomMap::ZoomLevelChange& change) {
 123   if (change.mode != content::HostZoomMap::ZOOM_CHANGED_FOR_HOST)
 124     return;
 125   double level = change.zoom_level;
 126   DictionaryPrefUpdate update(pref_service_,
 127                               prefs::kPartitionPerHostZoomLevels);
 128   base::DictionaryValue* host_zoom_dictionaries = update.Get();
 129   DCHECK(host_zoom_dictionaries);
 130
 131   bool modification_is_removal =
 132       content::ZoomValuesEqual(level, host_zoom_map_->GetDefaultZoomLevel());
 133
 134   base::DictionaryValue* host_zoom_dictionary = nullptr;
 135   if (!host_zoom_dictionaries->GetDictionary(partition_key_,
 136                                              &host_zoom_dictionary)) {
 137     host_zoom_dictionary = new base::DictionaryValue();
 138     host_zoom_dictionaries->Set(partition_key_, host_zoom_dictionary);
 139   }
 140
 141   if (modification_is_removal)
 142     host_zoom_dictionary->RemoveWithoutPathExpansion(change.host, nullptr);
 143   else
 144     host_zoom_dictionary->SetDoubleWithoutPathExpansion(change.host, level);
 145 }
 146
 147 void ChromeZoomLevelPrefs::ExtractPerHostZoomLevels(
 148     const base::DictionaryValue* host_zoom_dictionary) {
 149   std::vector<std::string> keys_to_remove;
 150   scoped_ptr<base::DictionaryValue> host_zoom_dictionary_copy(
 151       host_zoom_dictionary->DeepCopyWithoutEmptyChildren());
 152   for (base::DictionaryValue::Iterator i(*host_zoom_dictionary_copy);
 153        !i.IsAtEnd();
 154        i.Advance()) {
 155     const std::string& host(i.key());
 156     double zoom_level = 0;
 157
 158     bool has_valid_zoom_level = i.value().GetAsDouble(&zoom_level);
 159
 160     // Filter out A) the empty host, B) zoom levels equal to the default; and
 161     // remember them, so that we can later erase them from Prefs.
 162     // Values of type A and B could have been stored due to crbug.com/364399.
 163     // Values of type B could further have been stored before the default zoom
 164     // level was set to its current value. In either case, SetZoomLevelForHost
 165     // will ignore type B values, thus, to have consistency with HostZoomMap's
 166     // internal state, these values must also be removed from Prefs.
 167     if (host.empty() || !has_valid_zoom_level ||
 168         content::ZoomValuesEqual(zoom_level,
 169                                  host_zoom_map_->GetDefaultZoomLevel())) {
 170       keys_to_remove.push_back(host);
 171       continue;
 172     }
 173
 174     host_zoom_map_->SetZoomLevelForHost(host, zoom_level);
 175   }
 176
 177   // Sanitize prefs to remove entries that match the default zoom level and/or
 178   // have an empty host.
 179   {
 180     DictionaryPrefUpdate update(pref_service_,
 181                                 prefs::kPartitionPerHostZoomLevels);
 182     base::DictionaryValue* host_zoom_dictionaries = update.Get();
 183     base::DictionaryValue* host_zoom_dictionary = nullptr;
 184     host_zoom_dictionaries->GetDictionary(partition_key_,
 185                                           &host_zoom_dictionary);
 186     for (const std::string& s : keys_to_remove)
 187       host_zoom_dictionary->RemoveWithoutPathExpansion(s, nullptr);
 188   }
 189 }
 190
 191 }  // namespace chrome