layout/style/CSSVariableResolver.h@6474c204b198 (annotated)
layout/style/CSSVariableResolver.h
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */ |
| michael@0 | 2 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 3 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 4 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 5 | |
| michael@0 | 6 | /* object that resolves CSS variables using specified and inherited variable |
| michael@0 | 7 | * values |
| michael@0 | 8 | */ |
| michael@0 | 9 | |
| michael@0 | 10 | #ifndef mozilla_CSSVariableResolver_h |
| michael@0 | 11 | #define mozilla_CSSVariableResolver_h |
| michael@0 | 12 | |
| michael@0 | 13 | #include "mozilla/DebugOnly.h" |
| michael@0 | 14 | #include "nsCSSParser.h" |
| michael@0 | 15 | #include "nsCSSScanner.h" |
| michael@0 | 16 | #include "nsDataHashtable.h" |
| michael@0 | 17 | #include "nsTArray.h" |
| michael@0 | 18 | |
| michael@0 | 19 | namespace mozilla { |
| michael@0 | 20 | |
| michael@0 | 21 | class CSSVariableDeclarations; |
| michael@0 | 22 | class CSSVariableValues; |
| michael@0 | 23 | class EnumerateVariableReferencesData; |
| michael@0 | 24 | |
| michael@0 | 25 | class CSSVariableResolver |
| michael@0 | 26 | { |
| michael@0 | 27 | friend class CSSVariableDeclarations; |
| michael@0 | 28 | friend class CSSVariableValues; |
| michael@0 | 29 | friend class EnumerateVariableReferencesData; |
| michael@0 | 30 | public: |
| michael@0 | 31 | /** |
| michael@0 | 32 | * Creates a new CSSVariableResolver that will output a set of resolved, |
| michael@0 | 33 | * computed variables into aOutput. |
| michael@0 | 34 | */ |
| michael@0 | 35 | CSSVariableResolver(CSSVariableValues* aOutput) |
| michael@0 | 36 | : mOutput(aOutput) |
| michael@0 | 37 | , mResolved(false) |
| michael@0 | 38 | { |
| michael@0 | 39 | MOZ_ASSERT(aOutput); |
| michael@0 | 40 | } |
| michael@0 | 41 | |
| michael@0 | 42 | /** |
| michael@0 | 43 | * Resolves the set of inherited variables from aInherited and the |
| michael@0 | 44 | * set of specified variables from aSpecified. The resoled variables |
| michael@0 | 45 | * are written in to mOutput. |
| michael@0 | 46 | */ |
| michael@0 | 47 | void Resolve(const CSSVariableValues* aInherited, |
| michael@0 | 48 | const CSSVariableDeclarations* aSpecified); |
| michael@0 | 49 | |
| michael@0 | 50 | private: |
| michael@0 | 51 | struct Variable |
| michael@0 | 52 | { |
| michael@0 | 53 | Variable(const nsAString& aVariableName, |
| michael@0 | 54 | nsString aValue, |
| michael@0 | 55 | nsCSSTokenSerializationType aFirstToken, |
| michael@0 | 56 | nsCSSTokenSerializationType aLastToken, |
| michael@0 | 57 | bool aWasInherited) |
| michael@0 | 58 | : mVariableName(aVariableName) |
| michael@0 | 59 | , mValue(aValue) |
| michael@0 | 60 | , mFirstToken(aFirstToken) |
| michael@0 | 61 | , mLastToken(aLastToken) |
| michael@0 | 62 | , mWasInherited(aWasInherited) |
| michael@0 | 63 | , mResolved(false) |
| michael@0 | 64 | , mReferencesNonExistentVariable(false) |
| michael@0 | 65 | , mInStack(false) |
| michael@0 | 66 | , mIndex(0) |
| michael@0 | 67 | , mLowLink(0) { } |
| michael@0 | 68 | |
| michael@0 | 69 | nsString mVariableName; |
| michael@0 | 70 | nsString mValue; |
| michael@0 | 71 | nsCSSTokenSerializationType mFirstToken; |
| michael@0 | 72 | nsCSSTokenSerializationType mLastToken; |
| michael@0 | 73 | |
| michael@0 | 74 | // Whether this variable came from the set of inherited variables. |
| michael@0 | 75 | bool mWasInherited; |
| michael@0 | 76 | |
| michael@0 | 77 | // Whether this variable has been resolved yet. |
| michael@0 | 78 | bool mResolved; |
| michael@0 | 79 | |
| michael@0 | 80 | // Whether this variables includes any references to non-existent variables. |
| michael@0 | 81 | bool mReferencesNonExistentVariable; |
| michael@0 | 82 | |
| michael@0 | 83 | // Bookkeeping for the cycle remover algorithm. |
| michael@0 | 84 | bool mInStack; |
| michael@0 | 85 | size_t mIndex; |
| michael@0 | 86 | size_t mLowLink; |
| michael@0 | 87 | }; |
| michael@0 | 88 | |
| michael@0 | 89 | /** |
| michael@0 | 90 | * Adds or modifies an existing entry in the set of variables to be resolved. |
| michael@0 | 91 | * This is intended to be called by the AddVariablesToResolver functions on |
| michael@0 | 92 | * the CSSVariableDeclarations and CSSVariableValues objects passed in to |
| michael@0 | 93 | * Resolve. |
| michael@0 | 94 | * |
| michael@0 | 95 | * @param aName The variable name (not including any "--" prefix that would |
| michael@0 | 96 | * be part of the custom property name) whose value is to be set. |
| michael@0 | 97 | * @param aValue The variable value. |
| michael@0 | 98 | * @param aFirstToken The type of token at the start of the variable value. |
| michael@0 | 99 | * @param aLastToken The type of token at the en of the variable value. |
| michael@0 | 100 | * @param aWasInherited Whether this variable came from the set of inherited |
| michael@0 | 101 | * variables. |
| michael@0 | 102 | */ |
| michael@0 | 103 | void Put(const nsAString& aVariableName, |
| michael@0 | 104 | nsString aValue, |
| michael@0 | 105 | nsCSSTokenSerializationType aFirstToken, |
| michael@0 | 106 | nsCSSTokenSerializationType aLastToken, |
| michael@0 | 107 | bool aWasInherited); |
| michael@0 | 108 | |
| michael@0 | 109 | // Helper functions for Resolve. |
| michael@0 | 110 | void RemoveCycles(size_t aID); |
| michael@0 | 111 | void ResolveVariable(size_t aID); |
| michael@0 | 112 | |
| michael@0 | 113 | // A mapping of variable names to an ID that indexes into mVariables |
| michael@0 | 114 | // and mReferences. |
| michael@0 | 115 | nsDataHashtable<nsStringHashKey, size_t> mVariableIDs; |
| michael@0 | 116 | |
| michael@0 | 117 | // The set of variables. |
| michael@0 | 118 | nsTArray<Variable> mVariables; |
| michael@0 | 119 | |
| michael@0 | 120 | // The list of variables that each variable references. |
| michael@0 | 121 | nsTArray<nsTArray<size_t> > mReferences; |
| michael@0 | 122 | |
| michael@0 | 123 | // The next index to assign to a variable found during the cycle removing |
| michael@0 | 124 | // algorithm's traversal of the variable reference graph. |
| michael@0 | 125 | size_t mNextIndex; |
| michael@0 | 126 | |
| michael@0 | 127 | // Stack of variable IDs that we push to as we traverse the variable reference |
| michael@0 | 128 | // graph while looking for cycles. Variable::mInStack reflects whether a |
| michael@0 | 129 | // given variable has its ID in mStack. |
| michael@0 | 130 | nsTArray<size_t> mStack; |
| michael@0 | 131 | |
| michael@0 | 132 | // CSS parser to use for parsing property values with variable references. |
| michael@0 | 133 | nsCSSParser mParser; |
| michael@0 | 134 | |
| michael@0 | 135 | // The object to output the resolved variables into. |
| michael@0 | 136 | CSSVariableValues* mOutput; |
| michael@0 | 137 | |
| michael@0 | 138 | // Whether Resolve has been called. |
| michael@0 | 139 | DebugOnly<bool> mResolved; |
| michael@0 | 140 | }; |
| michael@0 | 141 | |
| michael@0 | 142 | } |
| michael@0 | 143 | |
| michael@0 | 144 | #endif |
