layout/style/ServoCSSParser.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /* CSS parsing utility functions */
   8
   9 #ifndef mozilla_ServoCSSParser_h
  10 #define mozilla_ServoCSSParser_h
  11
  12 #include "mozilla/gfx/Types.h"
  13 #include "mozilla/RefPtr.h"
  14 #include "mozilla/ServoStyleConsts.h"
  15 #include "mozilla/ServoTypes.h"
  16 #include "nsColor.h"
  17 #include "nsCSSPropertyID.h"
  18 #include "nsDOMCSSDeclaration.h"
  19 #include "nsStringFwd.h"
  20
  21 struct nsCSSRect;
  22 struct nsTimingFunction;
  23 struct RawServoDeclarationBlock;
  24
  25 namespace mozilla {
  26
  27 class ServoStyleSet;
  28 class SharedFontList;
  29 struct URLExtraData;
  30
  31 namespace css {
  32 class Loader;
  33 }
  34
  35 namespace dom {
  36 class Document;
  37 }
  38
  39 class ServoCSSParser {
  40  public:
  41   using ParsingEnvironment = nsDOMCSSDeclaration::ParsingEnvironment;
  42
  43   /**
  44    * Returns whether the specified string can be parsed as a valid CSS
  45    * <color> value.
  46    *
  47    * This includes Mozilla-specific keywords such as -moz-default-color.
  48    */
  49   static bool IsValidCSSColor(const nsACString& aValue);
  50
  51   /**
  52    * Computes an nscolor from the given CSS <color> value.
  53    *
  54    * @param aStyleSet The style set whose nsPresContext will be used to
  55    *   compute system colors and other special color values.
  56    * @param aCurrentColor The color value that currentcolor should compute to.
  57    * @param aValue The CSS <color> value.
  58    * @param aResultColor The resulting computed color value.
  59    * @param aWasCurrentColor Whether aValue was currentcolor. Can be nullptr
  60    *   if the caller doesn't care.
  61    * @param aLoader The CSS loader for document we're parsing a color for,
  62    *   so that parse errors can be reported to the console. If nullptr, errors
  63    *   won't be reported to the console.
  64    * @return Whether aValue was successfully parsed and aResultColor was set.
  65    */
  66   static bool ComputeColor(ServoStyleSet* aStyleSet, nscolor aCurrentColor,
  67                            const nsACString& aValue, nscolor* aResultColor,
  68                            bool* aWasCurrentColor = nullptr,
  69                            css::Loader* aLoader = nullptr);
  70
  71   /**
  72    * Parse a string representing a CSS property value into a
  73    * RawServoDeclarationBlock.
  74    *
  75    * @param aProperty The property to be parsed.
  76    * @param aValue The specified value.
  77    * @param aParsingEnvironment All the parsing environment data we need.
  78    * @param aParsingMode The paring mode we apply.
  79    * @return The parsed value as a RawServoDeclarationBlock. We put the value
  80    *   in a declaration block since that is how we represent specified values
  81    *   in Servo.
  82    */
  83   static already_AddRefed<RawServoDeclarationBlock> ParseProperty(
  84       nsCSSPropertyID aProperty, const nsAString& aValue,
  85       const ParsingEnvironment& aParsingEnvironment,
  86       ParsingMode aParsingMode = ParsingMode::Default);
  87
  88   /**
  89    * Parse a animation timing function.
  90    *
  91    * @param aValue The specified value.
  92    * @param aUrl The parser url extra data.
  93    * @param aResult The output timing function. (output)
  94    * @return Whether the value was successfully parsed.
  95    */
  96   static bool ParseEasing(const nsAString& aValue, URLExtraData* aUrl,
  97                           nsTimingFunction& aResult);
  98
  99   /**
 100    * Parse a specified transform list into a gfx matrix.
 101    *
 102    * @param aValue The specified value.
 103    * @param aContains3DTransform The output flag indicates whether this is any
 104    *   3d transform function. (output)
 105    * @param aResult The output matrix. (output)
 106    * @return Whether the value was successfully parsed.
 107    */
 108   static bool ParseTransformIntoMatrix(const nsACString& aValue,
 109                                        bool& aContains3DTransform,
 110                                        gfx::Matrix4x4& aResult);
 111
 112   /**
 113    * Parse a font shorthand for FontFaceSet matching, so we only care about
 114    * FontFamily, FontStyle, FontStretch, and FontWeight.
 115    *
 116    * @param aValue The specified value.
 117    * @param aUrl The parser url extra data.
 118    * @param aList The parsed FontFamily list. (output)
 119    * @param aStyle The parsed FontStyle. (output)
 120    * @param aStretch The parsed FontStretch. (output)
 121    * @param aWeight The parsed FontWeight. (output)
 122    * @return Whether the value was successfully parsed.
 123    */
 124   static bool ParseFontShorthandForMatching(
 125       const nsAString& aValue, URLExtraData* aUrl,
 126       RefPtr<SharedFontList>& aList, StyleComputedFontStyleDescriptor& aStyle,
 127       float& aStretch, float& aWeight);
 128
 129   /**
 130    * Get a URLExtraData from a document.
 131    */
 132   static already_AddRefed<URLExtraData> GetURLExtraData(dom::Document*);
 133
 134   /**
 135    * Get a ParsingEnvironment from a document.
 136    */
 137   static ParsingEnvironment GetParsingEnvironment(dom::Document*);
 138 };
 139
 140 }  // namespace mozilla
 141
 142 #endif  // mozilla_ServoCSSParser_h