1 files changed, 247 insertions, 0 deletions
diff --git a/layout/style/nsCSSProps.cpp b/layout/style/nsCSSProps.cpp
new file mode 100644
index 0000000000..5f2f275d6e
--- /dev/null
+++ b/layout/style/nsCSSProps.cpp
@@ -0,0 +1,247 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * methods for dealing with CSS properties and tables of the keyword
+ * values they accept
+ */
+
+#include "nsCSSProps.h"
+
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/Casting.h"
+
+#include "gfxPlatform.h"
+#include "nsLayoutUtils.h"
+#include "nsIWidget.h"
+#include "nsStyleConsts.h"  // For system widget appearance types
+
+#include "mozilla/dom/Animation.h"
+#include "mozilla/dom/AnimationEffectBinding.h"  // for PlaybackDirection
+#include "mozilla/gfx/gfxVars.h"                 // for UseWebRender
+#include "mozilla/gfx/gfxVarReceiver.h"
+#include "mozilla/LookAndFeel.h"  // for system colors
+
+#include "nsString.h"
+#include "nsStaticNameTable.h"
+
+#include "mozilla/Preferences.h"
+#include "mozilla/StaticPrefs_layout.h"
+#include "mozilla/StaticPtr.h"
+#include "mozilla/ClearOnShutdown.h"
+
+using namespace mozilla;
+
+static StaticAutoPtr<nsStaticCaseInsensitiveNameTable> gFontDescTable;
+static StaticAutoPtr<nsStaticCaseInsensitiveNameTable> gCounterDescTable;
+static StaticAutoPtr<nsTHashMap<nsCStringHashKey, nsCSSPropertyID>>
+    gPropertyIDLNameTable;
+
+static constexpr const char* const kCSSRawFontDescs[] = {
+#define CSS_FONT_DESC(name_, method_) #name_,
+#include "nsCSSFontDescList.h"
+#undef CSS_FONT_DESC
+};
+
+static constexpr const char* const kCSSRawCounterDescs[] = {
+#define CSS_COUNTER_DESC(name_, method_) #name_,
+#include "nsCSSCounterDescList.h"
+#undef CSS_COUNTER_DESC
+};
+
+static constexpr CSSPropFlags kFlagsTable[eCSSProperty_COUNT_with_aliases] = {
+#define CSS_PROP_LONGHAND(name_, id_, method_, flags_, ...) flags_,
+#define CSS_PROP_SHORTHAND(name_, id_, method_, flags_, ...) flags_,
+#define CSS_PROP_ALIAS(name_, aliasid_, id_, method_, flags_, ...) flags_,
+#include "mozilla/ServoCSSPropList.h"
+#undef CSS_PROP_ALIAS
+#undef CSS_PROP_SHORTHAND
+#undef CSS_PROP_LONGHAND
+};
+
+static nsStaticCaseInsensitiveNameTable* CreateStaticTable(
+    const char* const aRawTable[], int32_t aLength) {
+  auto* table = new nsStaticCaseInsensitiveNameTable(aRawTable, aLength);
+#ifdef DEBUG
+  // Partially verify the entries.
+  for (int32_t index = 0; index < aLength; ++index) {
+    nsAutoCString temp(aRawTable[index]);
+    MOZ_ASSERT(-1 == temp.FindChar('_'),
+               "underscore char in case insensitive name table");
+  }
+#endif
+  return table;
+}
+
+void nsCSSProps::RecomputeEnabledState(const char* aPref, void*) {
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  DebugOnly<bool> foundPref = false;
+  for (const PropertyPref* pref = kPropertyPrefTable;
+       pref->mPropID != eCSSProperty_UNKNOWN; pref++) {
+    if (!aPref || !strcmp(aPref, pref->mPref)) {
+      foundPref = true;
+#ifdef FUZZING
+      gPropertyEnabled[pref->mPropID] = true;
+#else
+      gPropertyEnabled[pref->mPropID] = Preferences::GetBool(pref->mPref);
+      if (pref->mPropID == eCSSProperty_backdrop_filter) {
+        gPropertyEnabled[pref->mPropID] &=
+            gfx::gfxVars::GetAllowBackdropFilterOrDefault();
+      }
+#endif
+    }
+  }
+  MOZ_ASSERT(foundPref);
+}
+
+void nsCSSProps::Init() {
+  MOZ_ASSERT(!gFontDescTable, "pre existing array!");
+  MOZ_ASSERT(!gCounterDescTable, "pre existing array!");
+  MOZ_ASSERT(!gPropertyIDLNameTable, "pre existing array!");
+
+  gFontDescTable = CreateStaticTable(kCSSRawFontDescs, eCSSFontDesc_COUNT);
+  gCounterDescTable =
+      CreateStaticTable(kCSSRawCounterDescs, eCSSCounterDesc_COUNT);
+
+  gPropertyIDLNameTable = new nsTHashMap<nsCStringHashKey, nsCSSPropertyID>;
+  for (nsCSSPropertyID p = nsCSSPropertyID(0);
+       size_t(p) < ArrayLength(kIDLNameTable); p = nsCSSPropertyID(p + 1)) {
+    if (kIDLNameTable[p]) {
+      gPropertyIDLNameTable->InsertOrUpdate(
+          nsDependentCString(kIDLNameTable[p]), p);
+    }
+  }
+
+  ClearOnShutdown(&gFontDescTable);
+  ClearOnShutdown(&gCounterDescTable);
+  ClearOnShutdown(&gPropertyIDLNameTable);
+
+  for (const PropertyPref* pref = kPropertyPrefTable;
+       pref->mPropID != eCSSProperty_UNKNOWN; pref++) {
+    // https://bugzilla.mozilla.org/show_bug.cgi?id=1472523
+    // We need to use nsCString instead of substring because the preference
+    // callback code stores them. Using AssignLiteral prevents any
+    // unnecessary allocations.
+    nsCString prefName;
+    prefName.AssignLiteral(pref->mPref, strlen(pref->mPref));
+    Preferences::RegisterCallback(nsCSSProps::RecomputeEnabledState, prefName);
+  }
+  RecomputeEnabledState(/* aPrefName = */ nullptr);
+}
+
+/* static */
+bool nsCSSProps::IsCustomPropertyName(const nsACString& aProperty) {
+  return aProperty.Length() >= CSS_CUSTOM_NAME_PREFIX_LENGTH &&
+         StringBeginsWith(aProperty, "--"_ns);
+}
+
+nsCSSPropertyID nsCSSProps::LookupPropertyByIDLName(
+    const nsACString& aPropertyIDLName, EnabledState aEnabled) {
+  MOZ_ASSERT(gPropertyIDLNameTable, "no lookup table, needs addref");
+  nsCSSPropertyID res;
+  if (!gPropertyIDLNameTable->Get(aPropertyIDLName, &res)) {
+    return eCSSProperty_UNKNOWN;
+  }
+  MOZ_ASSERT(res < eCSSProperty_COUNT);
+  if (!IsEnabled(res, aEnabled)) {
+    return eCSSProperty_UNKNOWN;
+  }
+  return res;
+}
+
+nsCSSFontDesc nsCSSProps::LookupFontDesc(const nsACString& aFontDesc) {
+  MOZ_ASSERT(gFontDescTable, "no lookup table, needs addref");
+  nsCSSFontDesc which = nsCSSFontDesc(gFontDescTable->Lookup(aFontDesc));
+
+  return which;
+}
+
+static constexpr auto sDescNullStr = ""_ns;
+
+const nsCString& nsCSSProps::GetStringValue(nsCSSFontDesc aFontDescID) {
+  MOZ_ASSERT(gFontDescTable, "no lookup table, needs addref");
+  if (gFontDescTable) {
+    return gFontDescTable->GetStringValue(int32_t(aFontDescID));
+  }
+  return sDescNullStr;
+}
+
+const nsCString& nsCSSProps::GetStringValue(nsCSSCounterDesc aCounterDescID) {
+  MOZ_ASSERT(gCounterDescTable, "no lookup table, needs addref");
+  if (gCounterDescTable) {
+    return gCounterDescTable->GetStringValue(int32_t(aCounterDescID));
+  }
+  return sDescNullStr;
+}
+
+CSSPropFlags nsCSSProps::PropFlags(nsCSSPropertyID aProperty) {
+  MOZ_ASSERT(0 <= aProperty && aProperty < eCSSProperty_COUNT_with_aliases,
+             "out of range");
+  return kFlagsTable[aProperty];
+}
+
+/* static */
+bool nsCSSProps::gPropertyEnabled[eCSSProperty_COUNT_with_aliases] = {
+// If the property has any "ENABLED_IN" flag set, it is disabled by
+// default. Note that, if a property has pref, whatever its default
+// value is, it will later be changed in nsCSSProps::AddRefTable().
+// If the property has "ENABLED_IN" flags but doesn't have a pref,
+// it is an internal property which is disabled elsewhere.
+#define IS_ENABLED_BY_DEFAULT(flags_) \
+  (!((flags_) & (CSSPropFlags::EnabledMask | CSSPropFlags::Inaccessible)))
+
+#define CSS_PROP_LONGHAND(name_, id_, method_, flags_, ...) \
+  IS_ENABLED_BY_DEFAULT(flags_),
+#define CSS_PROP_SHORTHAND(name_, id_, method_, flags_, ...) \
+  IS_ENABLED_BY_DEFAULT(flags_),
+#define CSS_PROP_ALIAS(name_, aliasid_, id_, method_, flags_, ...) \
+  IS_ENABLED_BY_DEFAULT(flags_),
+#include "mozilla/ServoCSSPropList.h"
+#undef CSS_PROP_ALIAS
+#undef CSS_PROP_SHORTHAND
+#undef CSS_PROP_LONGHAND
+
+#undef IS_ENABLED_BY_DEFAULT
+};
+
+/**
+ * A singleton class to register as a receiver for gfxVars.
+ * Updates the state of backdrop-filter's pref if the gfx
+ * backdrop filter var changes state.
+ */
+class nsCSSPropsGfxVarReceiver final : public gfx::gfxVarReceiver {
+  constexpr nsCSSPropsGfxVarReceiver() = default;
+
+  // Backdrop filter's last known enabled state.
+  static bool sLastKnownAllowBackdropFilter;
+  static nsCSSPropsGfxVarReceiver sInstance;
+
+ public:
+  static gfx::gfxVarReceiver& GetInstance() { return sInstance; }
+
+  void OnVarChanged(const gfx::GfxVarUpdate&) override {
+    bool enabled = gfx::gfxVars::AllowBackdropFilter();
+    if (sLastKnownAllowBackdropFilter != enabled) {
+      sLastKnownAllowBackdropFilter = enabled;
+      nsCSSProps::RecomputeEnabledState(
+          StaticPrefs::GetPrefName_layout_css_backdrop_filter_enabled());
+    }
+  }
+};
+
+/* static */
+nsCSSPropsGfxVarReceiver nsCSSPropsGfxVarReceiver::sInstance =
+    nsCSSPropsGfxVarReceiver();
+
+/* static */
+bool nsCSSPropsGfxVarReceiver::sLastKnownAllowBackdropFilter = true;
+
+/* static */
+gfx::gfxVarReceiver& nsCSSProps::GfxVarReceiver() {
+  return nsCSSPropsGfxVarReceiver::GetInstance();
+}
+
+#include "nsCSSPropsGenerated.inc"