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/AlreadyAddRefed.h"
  13 #include "mozilla/gfx/Matrix.h"
  14 #include "mozilla/ServoTypes.h"
  15 #include "nsColor.h"
  16 #include "nsCSSPropertyID.h"
  17 #include "nsDOMCSSDeclaration.h"
  18 #include "nsStringFwd.h"
  19
  20 struct nsCSSRect;
  21 struct nsTimingFunction;
  22 struct RawServoDeclarationBlock;
  23 template <class T>
  24 class RefPtr;
  25
  26 namespace mozilla {
  27
  28 class ServoStyleSet;
  29 class SharedFontList;
  30 struct URLExtraData;
  31 union StyleComputedFontStyleDescriptor;
  32
  33 namespace css {
  34 class Loader;
  35 }
  36
  37 namespace dom {
  38 class Document;
  39 }
  40
  41 class ServoCSSParser {
  42  public:
  43   using ParsingEnvironment = nsDOMCSSDeclaration::ParsingEnvironment;
  44
  45   /**
  46    * Returns whether the specified string can be parsed as a valid CSS
  47    * <color> value.
  48    *
  49    * This includes Mozilla-specific keywords such as -moz-default-color.
  50    */
  51   static bool IsValidCSSColor(const nsACString& aValue);
  52
  53   /**
  54    * Computes an nscolor from the given CSS <color> value.
  55    *
  56    * @param aStyleSet The style set whose nsPresContext will be used to
  57    *   compute system colors and other special color values.
  58    * @param aCurrentColor The color value that currentcolor should compute to.
  59    * @param aValue The CSS <color> value.
  60    * @param aResultColor The resulting computed color value.
  61    * @param aWasCurrentColor Whether aValue was currentcolor. Can be nullptr
  62    *   if the caller doesn't care.
  63    * @param aLoader The CSS loader for document we're parsing a color for,
  64    *   so that parse errors can be reported to the console. If nullptr, errors
  65    *   won't be reported to the console.
  66    * @return Whether aValue was successfully parsed and aResultColor was set.
  67    */
  68   static bool ComputeColor(ServoStyleSet* aStyleSet, nscolor aCurrentColor,
  69                            const nsACString& aValue, nscolor* aResultColor,
  70                            bool* aWasCurrentColor = nullptr,
  71                            css::Loader* aLoader = nullptr);
  72
  73   /**
  74    * Parse a string representing a CSS property value into a
  75    * RawServoDeclarationBlock.
  76    *
  77    * @param aProperty The property to be parsed.
  78    * @param aValue The specified value.
  79    * @param aParsingEnvironment All the parsing environment data we need.
  80    * @param aParsingMode The paring mode we apply.
  81    * @return The parsed value as a RawServoDeclarationBlock. We put the value
  82    *   in a declaration block since that is how we represent specified values
  83    *   in Servo.
  84    */
  85   static already_AddRefed<RawServoDeclarationBlock> ParseProperty(
  86       nsCSSPropertyID aProperty, const nsACString& aValue,
  87       const ParsingEnvironment& aParsingEnvironment,
  88       ParsingMode aParsingMode = ParsingMode::Default);
  89
  90   /**
  91    * Parse a animation timing function.
  92    *
  93    * @param aValue The specified value.
  94    * @param aResult The output timing function. (output)
  95    * @return Whether the value was successfully parsed.
  96    */
  97   static bool ParseEasing(const nsACString& aValue, 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 nsACString& 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