The Tor Browser: layout/style/nsCSSScanner.h@925c144e1f1f (annotated)

layout/style/nsCSSScanner.h@925c144e1f1f (annotated)

layout/style/nsCSSScanner.h

Fri, 16 Jan 2015 18:13:44 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 18:13:44 +0100
branch: TOR_BUG_9701
changeset 14: 925c144e1f1f
permissions: -rw-r--r--

Integrate suggestion from review to improve consistency with existing code.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* 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/. */
 /* tokenization of CSS style sheets */
 #ifndef nsCSSScanner_h___
 #define nsCSSScanner_h___
 #include "nsString.h"
 namespace mozilla {
 namespace css {
 class ErrorReporter;
 }
 }
 // Token types; in close but not perfect correspondence to the token
 // categorization in section 4.1.1 of CSS2.1.  (The deviations are all
 // the fault of css3-selectors, which has requirements that can only be
 // met by changing the generic tokenization.)  The comment on each line
 // illustrates the form of each identifier.
 enum nsCSSTokenType {
   // White space of any kind.  No value fields are used.  Note that
   // comments do *not* count as white space; comments separate tokens
   // but are not themselves tokens.
   eCSSToken_Whitespace,     //
   // Identifier-like tokens.  mIdent is the text of the identifier.
   // The difference between ID and Hash is: if the text after the #
   // would have been a valid Ident if the # hadn't been there, the
   // scanner produces an ID token.  Otherwise it produces a Hash token.
   // (This distinction is required by css3-selectors.)
   eCSSToken_Ident,          // word
   eCSSToken_Function,       // word(
   eCSSToken_AtKeyword,      // @word
   eCSSToken_ID,             // #word
   eCSSToken_Hash,           // #0word
   // Numeric tokens.  mNumber is the floating-point value of the
   // number, and mHasSign indicates whether there was an explicit sign
   // (+ or -) in front of the number.  If mIntegerValid is true, the
   // number had the lexical form of an integer, and mInteger is its
   // integer value.  Lexically integer values outside the range of a
   // 32-bit signed number are clamped to the maximum values; mNumber
   // will indicate a 'truer' value in that case.  Percentage tokens
   // are always considered not to be integers, even if their numeric
   // value is integral (100% => mNumber = 1.0).  For Dimension
   // tokens, mIdent holds the text of the unit.
   eCSSToken_Number,         // 1 -5 +2e3 3.14159 7.297352e-3
   eCSSToken_Dimension,      // 24px 8.5in
   eCSSToken_Percentage,     // 85% 1280.4%
   // String-like tokens.  In all cases, mIdent holds the text
   // belonging to the string, and mSymbol holds the delimiter
   // character, which may be ', ", or zero (only for unquoted URLs).
   // Bad_String and Bad_URL tokens are emitted when the closing
   // delimiter or parenthesis was missing.
   eCSSToken_String,         // 'foo bar' "foo bar"
   eCSSToken_Bad_String,     // 'foo bar
   eCSSToken_URL,            // url(foobar) url("foo bar")
   eCSSToken_Bad_URL,        // url(foo
   // Any one-character symbol.  mSymbol holds the character.
   eCSSToken_Symbol,         // . ; { } ! *
   // Match operators.  These are single tokens rather than pairs of
   // Symbol tokens because css3-selectors forbids the presence of
   // comments between the two characters.  No value fields are used;
   // the token type indicates which operator.
   eCSSToken_Includes,       // ~=
   eCSSToken_Dashmatch,      // |=
   eCSSToken_Beginsmatch,    // ^=
   eCSSToken_Endsmatch,      // $=
   eCSSToken_Containsmatch,  // *=
   // Unicode-range token: currently used only in @font-face.
   // The lexical rule for this token includes several forms that are
   // semantically invalid.  Therefore, mIdent always holds the
   // complete original text of the token (so we can print it
   // accurately in diagnostics), and mIntegerValid is true iff the
   // token is semantically valid.  In that case, mInteger holds the
   // lowest value included in the range, and mInteger2 holds the
   // highest value included in the range.
   eCSSToken_URange,         // U+007e U+01?? U+2000-206F
   // HTML comment delimiters, ignored as a unit when they appear at
   // the top level of a style sheet, for compatibility with websites
   // written for compatibility with pre-CSS browsers.  This token type
   // subsumes the css2.1 CDO and CDC tokens, which are always treated
   // the same by the parser.  mIdent holds the text of the token, for
   // diagnostics.
   eCSSToken_HTMLComment,    // <!-- -->
 };
 // Classification of tokens used to determine if a "/**/" string must be
 // inserted if pasting token streams together when serializing.  We include
 // values corresponding to eCSSToken_Dashmatch and eCSSToken_Containsmatch,
 // as css-syntax does not treat these as whole tokens, but we will still
 // need to insert a "/**/" string between a '|' delim and a '|=' dashmatch
 // and between a '/' delim and a '*=' containsmatch.
 //
 // https://dvcs.w3.org/hg/csswg/raw-file/372e659027a0/css-syntax/Overview.html#serialization
 enum nsCSSTokenSerializationType {
   eCSSTokenSerialization_Nothing,
   eCSSTokenSerialization_Whitespace,
   eCSSTokenSerialization_AtKeyword_or_Hash,
   eCSSTokenSerialization_Number,
   eCSSTokenSerialization_Dimension,
   eCSSTokenSerialization_Percentage,
   eCSSTokenSerialization_URange,
   eCSSTokenSerialization_URL_or_BadURL,
   eCSSTokenSerialization_Function,
   eCSSTokenSerialization_Ident,
   eCSSTokenSerialization_CDC,
   eCSSTokenSerialization_DashMatch,
   eCSSTokenSerialization_ContainsMatch,
   eCSSTokenSerialization_Symbol_Hash,         // '#'
   eCSSTokenSerialization_Symbol_At,           // '@'
   eCSSTokenSerialization_Symbol_Dot_or_Plus,  // '.', '+'
   eCSSTokenSerialization_Symbol_Minus,        // '-'
   eCSSTokenSerialization_Symbol_OpenParen,    // '('
   eCSSTokenSerialization_Symbol_Question,     // '?'
   eCSSTokenSerialization_Symbol_Assorted,     // '$', '^', '~'
   eCSSTokenSerialization_Symbol_Equals,       // '='
   eCSSTokenSerialization_Symbol_Bar,          // '|'
   eCSSTokenSerialization_Symbol_Slash,        // '/'
   eCSSTokenSerialization_Symbol_Asterisk,     // '*'
   eCSSTokenSerialization_Other                // anything else
 };
 // A single token returned from the scanner.  mType is always
 // meaningful; comments above describe which other fields are
 // meaningful for which token types.
 struct nsCSSToken {
   nsAutoString    mIdent;
   float           mNumber;
   int32_t         mInteger;
   int32_t         mInteger2;
   nsCSSTokenType  mType;
   char16_t       mSymbol;
   bool            mIntegerValid;
   bool            mHasSign;
   nsCSSToken()
     : mNumber(0), mInteger(0), mInteger2(0), mType(eCSSToken_Whitespace),
       mSymbol('\0'), mIntegerValid(false), mHasSign(false)
   {}
   bool IsSymbol(char16_t aSymbol) const {
     return mType == eCSSToken_Symbol && mSymbol == aSymbol;
   }
   void AppendToString(nsString& aBuffer) const;
 };
 // Represents an nsCSSScanner's saved position in the input buffer.
 class nsCSSScannerPosition {
   friend class nsCSSScanner;
 public:
   nsCSSScannerPosition() : mInitialized(false) { }
   uint32_t LineNumber() {
     MOZ_ASSERT(mInitialized);
     return mLineNumber;
   }
   uint32_t LineOffset() {
     MOZ_ASSERT(mInitialized);
     return mLineOffset;
   }
 private:
   uint32_t mOffset;
   uint32_t mLineNumber;
   uint32_t mLineOffset;
   uint32_t mTokenLineNumber;
   uint32_t mTokenLineOffset;
   uint32_t mTokenOffset;
   bool mInitialized;
 };
 // nsCSSScanner tokenizes an input stream using the CSS2.1 forward
 // compatible tokenization rules.  Used internally by nsCSSParser;
 // not available for use by other code.
 class nsCSSScanner {
   public:
   // |aLineNumber == 1| is the beginning of a file, use |aLineNumber == 0|
   // when the line number is unknown.
   nsCSSScanner(const nsAString& aBuffer, uint32_t aLineNumber);
   ~nsCSSScanner();
   void SetErrorReporter(mozilla::css::ErrorReporter* aReporter) {
     mReporter = aReporter;
   }
   // Set whether or not we are processing SVG
   void SetSVGMode(bool aSVGMode) {
     mSVGMode = aSVGMode;
   }
   bool IsSVGMode() const {
     return mSVGMode;
   }
   // Reset or check whether a BAD_URL or BAD_STRING token has been seen.
   void ClearSeenBadToken() { mSeenBadToken = false; }
   bool SeenBadToken() const { return mSeenBadToken; }
   // Reset or check whether a "var(" FUNCTION token has been seen.
   void ClearSeenVariableReference() { mSeenVariableReference = false; }
   bool SeenVariableReference() const { return mSeenVariableReference; }
   // Get the 1-based line number of the last character of
   // the most recently processed token.
   uint32_t GetLineNumber() const { return mTokenLineNumber; }
   // Get the 0-based column number of the first character of
   // the most recently processed token.
   uint32_t GetColumnNumber() const
   { return mTokenOffset - mTokenLineOffset; }
   // Get the text of the line containing the first character of
   // the most recently processed token.
   nsDependentSubstring GetCurrentLine() const;
   // Get the next token.  Return false on EOF.  aTokenResult is filled
   // in with the data for the token.  If aSkipWS is true, skip over
   // eCSSToken_Whitespace tokens rather than returning them.
   bool Next(nsCSSToken& aTokenResult, bool aSkipWS);
   // Get the body of an URL token (everything after the 'url(').
   // This is exposed for use by nsCSSParser::ParseMozDocumentRule,
   // which, for historical reasons, must make additional function
   // tokens behave like url().  Please do not add new uses to the
   // parser.
   bool NextURL(nsCSSToken& aTokenResult);
   // This is exposed for use by nsCSSParser::ParsePseudoClassWithNthPairArg,
   // because "2n-1" is a single DIMENSION token, and "n-1" is a single
   // IDENT token, but the :nth() selector syntax wants to interpret
   // them the same as "2n -1" and "n -1" respectively.  Please do not
   // add new uses to the parser.
   //
   // Note: this function may not be used to back up over a line boundary.
   void Backup(uint32_t n);
   // Starts recording the input stream from the current position.
   void StartRecording();
   // Abandons recording of the input stream.
   void StopRecording();
   // Stops recording of the input stream and appends the recorded
   // input to aBuffer.
   void StopRecording(nsString& aBuffer);
   // Returns the length of the current recording.
   uint32_t RecordingLength() const;
 #ifdef DEBUG
   bool IsRecording() const;
 #endif
   // Stores the current scanner offset into the specified object.
   void SavePosition(nsCSSScannerPosition& aState);
   // Resets the scanner offset to a position saved by SavePosition.
   void RestoreSavedPosition(const nsCSSScannerPosition& aState);
   enum EOFCharacters {
     eEOFCharacters_None =                    0x0000,
     // to handle \<EOF> inside strings
     eEOFCharacters_DropBackslash =           0x0001,
     // to handle \<EOF> outside strings
     eEOFCharacters_ReplacementChar =         0x0002,
     // to close comments
     eEOFCharacters_Asterisk =                0x0004,
     eEOFCharacters_Slash =                   0x0008,
     // to close double-quoted strings
     eEOFCharacters_DoubleQuote =             0x0010,
     // to close single-quoted strings
     eEOFCharacters_SingleQuote =             0x0020,
     // to close URLs
     eEOFCharacters_CloseParen =              0x0040,
   };
   // Appends any characters to the specified string the input stream to make the
   // last token not rely on special EOF handling behavior.
   //
   // If eEOFCharacters_DropBackslash is in aEOFCharacters, it is ignored.
   static void AppendImpliedEOFCharacters(EOFCharacters aEOFCharacters,
                                          nsAString& aString);
   EOFCharacters GetEOFCharacters() const {
 #ifdef DEBUG
     AssertEOFCharactersValid(mEOFCharacters);
 #endif
     return mEOFCharacters;
   }
 #ifdef DEBUG
   static void AssertEOFCharactersValid(uint32_t c);
 #endif
 protected:
   int32_t Peek(uint32_t n = 0);
   void Advance(uint32_t n = 1);
   void AdvanceLine();
   void SkipWhitespace();
   void SkipComment();
   bool GatherEscape(nsString& aOutput, bool aInString);
   bool GatherText(uint8_t aClass, nsString& aIdent);
   bool ScanIdent(nsCSSToken& aResult);
   bool ScanAtKeyword(nsCSSToken& aResult);
   bool ScanHash(nsCSSToken& aResult);
   bool ScanNumber(nsCSSToken& aResult);
   bool ScanString(nsCSSToken& aResult);
   bool ScanURange(nsCSSToken& aResult);
   void SetEOFCharacters(uint32_t aEOFCharacters);
   void AddEOFCharacters(uint32_t aEOFCharacters);
   const char16_t *mBuffer;
   uint32_t mOffset;
   uint32_t mCount;
   uint32_t mLineNumber;
   uint32_t mLineOffset;
   uint32_t mTokenLineNumber;
   uint32_t mTokenLineOffset;
   uint32_t mTokenOffset;
   uint32_t mRecordStartOffset;
   EOFCharacters mEOFCharacters;
   mozilla::css::ErrorReporter *mReporter;
   // True if we are in SVG mode; false in "normal" CSS
   bool mSVGMode;
   bool mRecording;
   bool mSeenBadToken;
   bool mSeenVariableReference;
 };
 // Token for the grid-template-areas micro-syntax
 // http://dev.w3.org/csswg/css-grid/#propdef-grid-template-areas
 struct MOZ_STACK_CLASS nsCSSGridTemplateAreaToken {
   nsAutoString mName;  // Empty for a null cell, non-empty for a named cell
   bool isTrash;  // True for a trash token, mName is ignored in this case.
 };
 // Scanner for the grid-template-areas micro-syntax
 class nsCSSGridTemplateAreaScanner {
 public:
   nsCSSGridTemplateAreaScanner(const nsAString& aBuffer);
   // Get the next token.  Return false on EOF.
   // aTokenResult is filled in with the data for the token.
   bool Next(nsCSSGridTemplateAreaToken& aTokenResult);
 private:
   const char16_t *mBuffer;
   uint32_t mOffset;
   uint32_t mCount;
 };
 #endif /* nsCSSScanner_h___ */

The Tor Browser / annotate

layout/style/nsCSSScanner.h@925c144e1f1f (annotated)

layout/style/nsCSSScanner.h