DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Implementation

Untracked file

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   L. David Baron <dbaron@dbaron.org>
 *   Daniel Glazman <glazman@netscape.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */
#ifndef nsCSSScanner_h___
#define nsCSSScanner_h___

#include "nsString.h"
#include "nsCOMPtr.h"
class nsIUnicharInputStream;

// XXX turn this off for minimo builds
#define CSS_REPORT_PARSE_ERRORS

// for #ifdef CSS_REPORT_PARSE_ERRORS
#include "nsXPIDLString.h"
class nsIURI;

// Token types
enum nsCSSTokenType {
  // A css identifier (e.g. foo)
  eCSSToken_Ident,          // mIdent

  // A css at keyword (e.g. @foo)
  eCSSToken_AtKeyword,      // mIdent

  // A css number without a percentage or dimension; with percentage;
  // without percentage but with a dimension
  eCSSToken_Number,         // mNumber
  eCSSToken_Percentage,     // mNumber
  eCSSToken_Dimension,      // mNumber + mIdent

  // A css string (e.g. "foo" or 'foo')
  eCSSToken_String,         // mSymbol + mIdent + mSymbol

  // Whitespace (e.g. " " or "/* abc */")
  eCSSToken_WhiteSpace,     // mIdent

  // A css symbol (e.g. ':', ';', '+', etc.)
  eCSSToken_Symbol,         // mSymbol

  // A css1 id (e.g. #foo3)
  eCSSToken_ID,             // mIdent
  // Just like eCSSToken_ID, except the part following the '#' is not
  // a valid CSS identifier (eg. starts with a digit, is the empty
  // string, etc).
  eCSSToken_Ref,            // mIdent

  eCSSToken_Function,       // mIdent

  eCSSToken_URL,            // mIdent
  eCSSToken_InvalidURL,     // doesn't matter

  eCSSToken_HTMLComment,    // "<!--" or "-->"

  eCSSToken_Includes,       // "~="
  eCSSToken_Dashmatch,      // "|="
  eCSSToken_Beginsmatch,    // "^="
  eCSSToken_Endsmatch,      // "$="
  eCSSToken_Containsmatch,  // "*="

  // A special token indicating that there was an error in tokenization.
  // It's always an unterminated string.
  eCSSToken_Error           // mSymbol + mIdent
};

struct nsCSSToken {
  nsCSSTokenType  mType;
  PRPackedBool    mIntegerValid;
  nsAutoString    mIdent;
  float           mNumber;
  PRInt32         mInteger;
  PRUnichar       mSymbol;

  nsCSSToken();

  PRBool IsDimension() {
    return PRBool((eCSSToken_Dimension == mType) ||
                  ((eCSSToken_Number == mType) && (mNumber == 0.0f)));
  }

  PRBool IsSymbol(PRUnichar aSymbol) {
    return PRBool((eCSSToken_Symbol == mType) && (mSymbol == aSymbol));
  }

  void AppendToString(nsString& aBuffer);
};

// CSS Scanner API. Used to tokenize an input stream using the CSS
// forward compatible tokenization rules. This implementation is
// private to this package and is only used internally by the css
// parser.
class nsCSSScanner {
  public:
  nsCSSScanner();
  ~nsCSSScanner();

  // Init the scanner.
  // |aLineNumber == 1| is the beginning of a file, use |aLineNumber == 0|
  // when the line number is unknown.
  void Init(nsIUnicharInputStream* aInput, nsIURI* aURI, PRUint32 aLineNumber);
  void Close();

  static PRBool InitGlobals();
  static void ReleaseGlobals();

#ifdef CSS_REPORT_PARSE_ERRORS
  NS_HIDDEN_(void) AddToError(const nsSubstring& aErrorText);
  NS_HIDDEN_(void) OutputError();
  NS_HIDDEN_(void) ClearError();

  // aMessage must take no parameters
  NS_HIDDEN_(void) ReportUnexpected(const char* aMessage);
  NS_HIDDEN_(void) ReportUnexpectedParams(const char* aMessage,
                                          const PRUnichar **aParams,
                                          PRUint32 aParamsLength);
  // aMessage must take no parameters
  NS_HIDDEN_(void) ReportUnexpectedEOF(const char* aLookingFor);
  // aMessage must take 1 parameter (for the string representation of the
  // unexpected token)
  NS_HIDDEN_(void) ReportUnexpectedToken(nsCSSToken& tok,
                                         const char *aMessage);
  // aParams's first entry must be null, and we'll fill in the token
  NS_HIDDEN_(void) ReportUnexpectedTokenParams(nsCSSToken& tok,
                                               const char* aMessage,
                                               const PRUnichar **aParams,
                                               PRUint32 aParamsLength);
#endif

  PRUint32 GetLineNumber() { return mLineNumber; }

  // Get the next token. Return PR_FALSE on EOF. aTokenResult
  // is filled in with the data for the token.
  PRBool Next(nsresult& aErrorCode, nsCSSToken& aTokenResult);

  // Get the next token that may be a string or unquoted URL or whitespace
  PRBool NextURL(nsresult& aErrorCode, nsCSSToken& aTokenResult);

  static inline PRBool
  IsIdentStart(PRInt32 aChar, const PRUint8* aLexTable)
  {
    return aChar >= 0 &&
      (aChar >= 256 || (aLexTable[aChar] & START_IDENT) != 0);
  }

  static inline PRBool
  StartsIdent(PRInt32 aFirstChar, PRInt32 aSecondChar,
              const PRUint8* aLexTable)
  {
    return IsIdentStart(aFirstChar, aLexTable) ||
      (aFirstChar == '-' && IsIdentStart(aSecondChar, aLexTable));
  }

  static inline const PRUint8* GetLexTable() {
    return gLexTable;
  }
  
protected:
  PRInt32 Read(nsresult& aErrorCode);
  PRInt32 Peek(nsresult& aErrorCode);
  void Unread();
  void Pushback(PRUnichar aChar);
  PRBool LookAhead(nsresult& aErrorCode, PRUnichar aChar);
  PRBool EatWhiteSpace(nsresult& aErrorCode);
  PRBool EatNewline(nsresult& aErrorCode);

  PRInt32 ParseEscape(nsresult& aErrorCode);
  PRBool ParseIdent(nsresult& aErrorCode, PRInt32 aChar, nsCSSToken& aResult);
  PRBool ParseAtKeyword(nsresult& aErrorCode, PRInt32 aChar,
                        nsCSSToken& aResult);
  PRBool ParseNumber(nsresult& aErrorCode, PRInt32 aChar, nsCSSToken& aResult);
  PRBool ParseRef(nsresult& aErrorCode, PRInt32 aChar, nsCSSToken& aResult);
  PRBool ParseString(nsresult& aErrorCode, PRInt32 aChar, nsCSSToken& aResult);
#if 0
  PRBool ParseEOLComment(nsresult& aErrorCode, nsCSSToken& aResult);
  PRBool ParseCComment(nsresult& aErrorCode, nsCSSToken& aResult);
#endif
  PRBool SkipCComment(nsresult& aErrorCode);

  PRBool GatherIdent(nsresult& aErrorCode, PRInt32 aChar, nsString& aIdent);

  nsCOMPtr<nsIUnicharInputStream> mInput;
  PRUnichar* mBuffer;
  PRInt32 mOffset;
  PRInt32 mCount;
  PRUnichar* mPushback;
  PRInt32 mPushbackCount;
  PRInt32 mPushbackSize;
  PRInt32 mLastRead;
  PRUnichar mLocalPushback[4];

  PRUint32 mLineNumber;
#ifdef CSS_REPORT_PARSE_ERRORS
  nsXPIDLCString mFileName;
  nsCOMPtr<nsIURI> mURI;  // Cached so we know to not refetch mFileName
  PRUint32 mErrorLineNumber, mColNumber, mErrorColNumber;
  nsFixedString mError;
  PRUnichar mErrorBuf[200];
#endif

  static const PRUint8 IS_DIGIT;
  static const PRUint8 IS_HEX_DIGIT;
  static const PRUint8 START_IDENT;
  static const PRUint8 IS_IDENT;
  static const PRUint8 IS_WHITESPACE;

  static PRUint8 gLexTable[256];
  static void BuildLexTable();
  static PRBool CheckLexTable(PRInt32 aChar, PRUint8 aBit, PRUint8* aLexTable);
};

#endif /* nsCSSScanner_h___ */