widget/RemoteLookAndFeel.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: sw=2 ts=8 et :
   3  */
   4 /* This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   7
   8 #include "RemoteLookAndFeel.h"
   9
  10 #include "gfxFont.h"
  11 #include "MainThreadUtils.h"
  12 #include "mozilla/Assertions.h"
  13 #include "mozilla/ClearOnShutdown.h"
  14 #include "mozilla/Result.h"
  15 #include "mozilla/ResultExtensions.h"
  16 #include "mozilla/StaticPrefs_widget.h"
  17 #include "nsLookAndFeel.h"
  18 #include "nsXULAppAPI.h"
  19
  20 #include <limits>
  21 #include <type_traits>
  22 #include <utility>
  23
  24 namespace mozilla::widget {
  25
  26 // A cached copy of the data extracted by ExtractData.
  27 //
  28 // Storing this lets us avoid doing most of the work of ExtractData each
  29 // time we create a new content process.
  30 //
  31 // Only used in the parent process.
  32 static StaticAutoPtr<FullLookAndFeel> sCachedLookAndFeelData;
  33
  34 RemoteLookAndFeel::RemoteLookAndFeel(FullLookAndFeel&& aData)
  35     : mTables(std::move(aData.tables())) {
  36   MOZ_ASSERT(XRE_IsContentProcess(),
  37              "Only content processes should be using a RemoteLookAndFeel");
  38
  39 #ifdef MOZ_WIDGET_GTK
  40   if (!StaticPrefs::widget_non_native_theme_enabled()) {
  41     // Configure the theme in this content process with the Gtk theme that was
  42     // chosen by WithThemeConfiguredForContent in the parent process.
  43     nsLookAndFeel::ConfigureTheme(aData.theme());
  44   }
  45 #endif
  46 }
  47
  48 RemoteLookAndFeel::~RemoteLookAndFeel() = default;
  49
  50 void RemoteLookAndFeel::SetDataImpl(FullLookAndFeel&& aData) {
  51   MOZ_ASSERT(XRE_IsContentProcess(),
  52              "Only content processes should be using a RemoteLookAndFeel");
  53   MOZ_ASSERT(NS_IsMainThread());
  54   mTables = std::move(aData.tables());
  55
  56 #ifdef MOZ_WIDGET_GTK
  57   if (!StaticPrefs::widget_non_native_theme_enabled()) {
  58     // Configure the theme in this content process with the Gtk theme that was
  59     // chosen by WithThemeConfiguredForContent in the parent process.
  60     nsLookAndFeel::ConfigureTheme(aData.theme());
  61   }
  62 #endif
  63 }
  64
  65 namespace {
  66
  67 // Some lnf values are somewhat expensive to get, and are not needed in child
  68 // processes, so we can avoid querying them.
  69 bool IsNeededInChildProcess(LookAndFeel::IntID aId) {
  70   switch (aId) {
  71     case LookAndFeel::IntID::AlertNotificationOrigin:
  72       return false;  // see bug 1703205
  73     default:
  74       return true;
  75   }
  76 }
  77
  78 template <typename Item, typename UInt, typename ID>
  79 Result<const Item*, nsresult> MapLookup(const nsTArray<Item>& aItems,
  80                                         const nsTArray<UInt>& aMap, ID aID) {
  81   UInt mapped = aMap[static_cast<size_t>(aID)];
  82
  83   if (mapped == std::numeric_limits<UInt>::max()) {
  84     return Err(NS_ERROR_NOT_IMPLEMENTED);
  85   }
  86
  87   return &aItems[static_cast<size_t>(mapped)];
  88 }
  89
  90 template <typename Item, typename UInt, typename Id>
  91 void AddToMap(nsTArray<Item>& aItems, nsTArray<UInt>& aMap, Id aId,
  92               Maybe<Item>&& aNewItem) {
  93   auto mapIndex = size_t(aId);
  94   aMap.EnsureLengthAtLeast(mapIndex + 1);
  95   if (aNewItem.isNothing()) {
  96     aMap[mapIndex] = std::numeric_limits<UInt>::max();
  97     return;
  98   }
  99
 100   size_t newIndex = aItems.Length();
 101   MOZ_ASSERT(newIndex < std::numeric_limits<UInt>::max());
 102
 103   // Check if there is an existing value in aItems that we can point to.
 104   //
 105   // The arrays should be small enough and contain few enough unique
 106   // values that sequential search here is reasonable.
 107   for (size_t i = 0; i < newIndex; ++i) {
 108     if (aItems[i] == aNewItem.ref()) {
 109       aMap[mapIndex] = static_cast<UInt>(i);
 110       return;
 111     }
 112   }
 113
 114   aItems.AppendElement(aNewItem.extract());
 115   aMap[mapIndex] = static_cast<UInt>(newIndex);
 116 }
 117
 118 }  // namespace
 119
 120 nsresult RemoteLookAndFeel::NativeGetColor(ColorID aID, ColorScheme aScheme,
 121                                            nscolor& aResult) {
 122   const nscolor* result;
 123   const bool dark = aScheme == ColorScheme::Dark;
 124   MOZ_TRY_VAR(
 125       result,
 126       MapLookup(dark ? mTables.darkColors() : mTables.lightColors(),
 127                 dark ? mTables.darkColorMap() : mTables.lightColorMap(), aID));
 128   aResult = *result;
 129   return NS_OK;
 130 }
 131
 132 nsresult RemoteLookAndFeel::NativeGetInt(IntID aID, int32_t& aResult) {
 133   MOZ_DIAGNOSTIC_ASSERT(
 134       IsNeededInChildProcess(aID),
 135       "Querying value that we didn't bother getting from the parent process!");
 136
 137   const int32_t* result;
 138   MOZ_TRY_VAR(result, MapLookup(mTables.ints(), mTables.intMap(), aID));
 139   aResult = *result;
 140   return NS_OK;
 141 }
 142
 143 nsresult RemoteLookAndFeel::NativeGetFloat(FloatID aID, float& aResult) {
 144   const float* result;
 145   MOZ_TRY_VAR(result, MapLookup(mTables.floats(), mTables.floatMap(), aID));
 146   aResult = *result;
 147   return NS_OK;
 148 }
 149
 150 bool RemoteLookAndFeel::NativeGetFont(FontID aID, nsString& aFontName,
 151                                       gfxFontStyle& aFontStyle) {
 152   auto result = MapLookup(mTables.fonts(), mTables.fontMap(), aID);
 153   if (result.isErr()) {
 154     return false;
 155   }
 156   const LookAndFeelFont& font = *result.unwrap();
 157   return LookAndFeelFontToStyle(font, aFontName, aFontStyle);
 158 }
 159
 160 char16_t RemoteLookAndFeel::GetPasswordCharacterImpl() {
 161   return static_cast<char16_t>(mTables.passwordChar());
 162 }
 163
 164 bool RemoteLookAndFeel::GetEchoPasswordImpl() { return mTables.passwordEcho(); }
 165
 166 static bool AddIDsToMap(nsXPLookAndFeel* aImpl, FullLookAndFeel* aLf,
 167                         bool aDifferentTheme, bool aFromParentTheme) {
 168   using IntID = LookAndFeel::IntID;
 169   using FontID = LookAndFeel::FontID;
 170   using FloatID = LookAndFeel::FloatID;
 171   using ColorID = LookAndFeel::ColorID;
 172   using ColorScheme = LookAndFeel::ColorScheme;
 173
 174   bool anyFromOtherTheme = false;
 175   for (auto id : MakeEnumeratedRange(IntID::End)) {
 176     if (!IsNeededInChildProcess(id)) {
 177       continue;
 178     }
 179     if (aDifferentTheme && aImpl->FromParentTheme(id) != aFromParentTheme) {
 180       anyFromOtherTheme = true;
 181       continue;
 182     }
 183     int32_t theInt;
 184     nsresult rv = aImpl->NativeGetInt(id, theInt);
 185     AddToMap(aLf->tables().ints(), aLf->tables().intMap(), id,
 186              NS_SUCCEEDED(rv) ? Some(theInt) : Nothing{});
 187   }
 188
 189   for (auto id : MakeEnumeratedRange(ColorID::End)) {
 190     if (aDifferentTheme && aImpl->FromParentTheme(id) != aFromParentTheme) {
 191       anyFromOtherTheme = true;
 192       continue;
 193     }
 194     nscolor theColor;
 195     nsresult rv = aImpl->NativeGetColor(id, ColorScheme::Light, theColor);
 196     AddToMap(aLf->tables().lightColors(), aLf->tables().lightColorMap(), id,
 197              NS_SUCCEEDED(rv) ? Some(theColor) : Nothing{});
 198     rv = aImpl->NativeGetColor(id, ColorScheme::Dark, theColor);
 199     AddToMap(aLf->tables().darkColors(), aLf->tables().darkColorMap(), id,
 200              NS_SUCCEEDED(rv) ? Some(theColor) : Nothing{});
 201   }
 202
 203   // The rest of IDs only come from the child content theme.
 204   if (aFromParentTheme) {
 205     return anyFromOtherTheme;
 206   }
 207
 208   for (auto id : MakeEnumeratedRange(FloatID::End)) {
 209     float theFloat;
 210     nsresult rv = aImpl->NativeGetFloat(id, theFloat);
 211     AddToMap(aLf->tables().floats(), aLf->tables().floatMap(), id,
 212              NS_SUCCEEDED(rv) ? Some(theFloat) : Nothing{});
 213   }
 214
 215   for (auto id : MakeEnumeratedRange(FontID::End)) {
 216     gfxFontStyle fontStyle{};
 217
 218     nsString name;
 219     bool rv = aImpl->NativeGetFont(id, name, fontStyle);
 220     Maybe<LookAndFeelFont> maybeFont;
 221     if (rv) {
 222       maybeFont.emplace(
 223           nsXPLookAndFeel::StyleToLookAndFeelFont(name, fontStyle));
 224     }
 225     AddToMap(aLf->tables().fonts(), aLf->tables().fontMap(), id,
 226              std::move(maybeFont));
 227   }
 228
 229   return anyFromOtherTheme;
 230 }
 231
 232 // static
 233 const FullLookAndFeel* RemoteLookAndFeel::ExtractData() {
 234   MOZ_ASSERT(XRE_IsParentProcess(),
 235              "Only parent processes should be extracting LookAndFeel data");
 236
 237   if (sCachedLookAndFeelData) {
 238     return sCachedLookAndFeelData;
 239   }
 240
 241   static bool sInitialized = false;
 242   if (!sInitialized) {
 243     sInitialized = true;
 244     ClearOnShutdown(&sCachedLookAndFeelData);
 245   }
 246
 247   FullLookAndFeel* lf = new FullLookAndFeel{};
 248   nsXPLookAndFeel* impl = nsXPLookAndFeel::GetInstance();
 249
 250   bool anyFromParent = false;
 251   impl->WithThemeConfiguredForContent([&](const LookAndFeelTheme& aTheme,
 252                                           bool aDifferentTheme) {
 253     anyFromParent =
 254         AddIDsToMap(impl, lf, aDifferentTheme, /* aFromParentTheme = */ false);
 255     MOZ_ASSERT_IF(anyFromParent, aDifferentTheme);
 256     lf->tables().passwordChar() = impl->GetPasswordCharacterImpl();
 257     lf->tables().passwordEcho() = impl->GetEchoPasswordImpl();
 258 #ifdef MOZ_WIDGET_GTK
 259     lf->theme() = aTheme;
 260 #endif
 261   });
 262
 263   if (anyFromParent) {
 264     AddIDsToMap(impl, lf, /* aDifferentTheme = */ true,
 265                 /* aFromParentTheme = */ true);
 266   }
 267
 268   // This assignment to sCachedLookAndFeelData must be done after the
 269   // WithThemeConfiguredForContent call, since it can end up calling RefreshImpl
 270   // on the LookAndFeel, which will clear out sCachedTables.
 271   sCachedLookAndFeelData = lf;
 272   return sCachedLookAndFeelData;
 273 }
 274
 275 void RemoteLookAndFeel::ClearCachedData() {
 276   MOZ_ASSERT(XRE_IsParentProcess());
 277   sCachedLookAndFeelData = nullptr;
 278 }
 279
 280 }  // namespace mozilla::widget