/* -*- 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/. */ /** * MODULE NOTES: * @update gess 4/1/98 * * The scanner is a low-level service class that knows * how to consume characters out of an (internal) stream. * This class also offers a series of utility methods * that most tokenizers want, such as readUntil() * and SkipWhitespace(). */ #ifndef SCANNER #define SCANNER #include "nsCOMPtr.h" #include "nsString.h" #include "nsIParser.h" #include "nsIUnicodeDecoder.h" #include "nsScannerString.h" class nsParser; class nsReadEndCondition { public: const char16_t *mChars; char16_t mFilter; explicit nsReadEndCondition(const char16_t* aTerminateChars); private: nsReadEndCondition(const nsReadEndCondition& aOther); // No copying void operator=(const nsReadEndCondition& aOther); // No assigning }; class nsScanner { public: /** * Use this constructor for the XML fragment parsing case */ explicit nsScanner(const nsAString& anHTMLString); /** * Use this constructor if you want i/o to be based on * a file (therefore a stream) or just data you provide via Append(). */ nsScanner(nsString& aFilename, bool aCreateStream); ~nsScanner(); /** * retrieve next char from internal input stream * * @update gess 3/25/98 * @param ch is the char to accept new value * @return error code reflecting read status */ nsresult GetChar(char16_t& ch); /** * peek ahead to consume next char from scanner's internal * input buffer * * @update gess 3/25/98 * @param ch is the char to accept new value * @return error code reflecting read status */ nsresult Peek(char16_t& ch, uint32_t aOffset=0); nsresult Peek(nsAString& aStr, int32_t aNumChars, int32_t aOffset = 0); /** * Skip over chars as long as they equal given char * * @update gess 3/25/98 * @param char to be skipped * @return error code */ nsresult SkipOver(char16_t aSkipChar); /** * Skip whitespace on scanner input stream * * @update gess 3/25/98 * @return error status */ nsresult SkipWhitespace(int32_t& aNewlinesSkipped); /** * Consume characters until you run into space, a '<', a '>', or a '/'. * * @param aString - receives new data from stream * @return error code */ nsresult ReadTagIdentifier(nsScannerSharedSubstring& aString); /** * Consume characters until you run into a char that's not valid in an * entity name * * @param aString - receives new data from stream * @return error code */ nsresult ReadEntityIdentifier(nsString& aString); nsresult ReadNumber(nsString& aString,int32_t aBase); nsresult ReadWhitespace(nsScannerSharedSubstring& aString, int32_t& aNewlinesSkipped, bool& aHaveCR); nsresult ReadWhitespace(nsScannerIterator& aStart, nsScannerIterator& aEnd, int32_t& aNewlinesSkipped); /** * Consume characters until you find the terminal char * * @update gess 3/25/98 * @param aString receives new data from stream * @param aTerminal contains terminating char * @param addTerminal tells us whether to append terminal to aString * @return error code */ nsresult ReadUntil(nsAString& aString, char16_t aTerminal, bool addTerminal); /** * Consume characters until you find one contained in given * terminal set. * * @update gess 3/25/98 * @param aString receives new data from stream * @param aTermSet contains set of terminating chars * @param addTerminal tells us whether to append terminal to aString * @return error code */ nsresult ReadUntil(nsAString& aString, const nsReadEndCondition& aEndCondition, bool addTerminal); nsresult ReadUntil(nsScannerSharedSubstring& aString, const nsReadEndCondition& aEndCondition, bool addTerminal); nsresult ReadUntil(nsScannerIterator& aStart, nsScannerIterator& aEnd, const nsReadEndCondition& aEndCondition, bool addTerminal); /** * Records current offset position in input stream. This allows us * to back up to this point if the need should arise, such as when * tokenization gets interrupted. * * @update gess 5/12/98 * @param * @return */ int32_t Mark(void); /** * Resets current offset position of input stream to marked position. * This allows us to back up to this point if the need should arise, * such as when tokenization gets interrupted. * NOTE: IT IS REALLY BAD FORM TO CALL RELEASE WITHOUT CALLING MARK FIRST! * * @update gess 5/12/98 * @param * @return */ void RewindToMark(void); /** * * * @update harishd 01/12/99 * @param * @return */ bool UngetReadable(const nsAString& aBuffer); /** * * * @update gess 5/13/98 * @param * @return */ nsresult Append(const nsAString& aBuffer); /** * * * @update gess 5/21/98 * @param * @return */ nsresult Append(const char* aBuffer, uint32_t aLen, nsIRequest *aRequest); /** * Call this to copy bytes out of the scanner that have not yet been consumed * by the tokenization process. * * @update gess 5/12/98 * @param aCopyBuffer is where the scanner buffer will be copied to * @return true if OK or false on OOM */ bool CopyUnusedData(nsString& aCopyBuffer); /** * Retrieve the name of the file that the scanner is reading from. * In some cases, it's just a given name, because the scanner isn't * really reading from a file. * * @update gess 5/12/98 * @return */ nsString& GetFilename(void); static void SelfTest(); /** * Use this setter to change the scanner's unicode decoder * * @update ftang 3/02/99 * @param aCharset a normalized (alias resolved) charset name * @param aCharsetSource- where the charset info came from * @return */ nsresult SetDocumentCharset(const nsACString& aCharset, int32_t aSource); void BindSubstring(nsScannerSubstring& aSubstring, const nsScannerIterator& aStart, const nsScannerIterator& aEnd); void CurrentPosition(nsScannerIterator& aPosition); void EndReading(nsScannerIterator& aPosition); void SetPosition(nsScannerIterator& aPosition, bool aTruncate = false, bool aReverse = false); void ReplaceCharacter(nsScannerIterator& aPosition, char16_t aChar); /** * Internal method used to cause the internal buffer to * be filled with data. * * @update gess4/3/98 */ bool IsIncremental(void) {return mIncremental;} void SetIncremental(bool anIncrValue) {mIncremental=anIncrValue;} /** * Return the position of the first non-whitespace * character. This is only reliable before consumers start * reading from this scanner. */ int32_t FirstNonWhitespacePosition() { return mFirstNonWhitespacePosition; } /** * Override replacement character used by nsIUnicodeDecoder. * Default behavior is that it uses nsIUnicodeDecoder's mapping. * * @param aReplacementCharacter the replacement character * XML (expat) parser uses 0xffff */ void OverrideReplacementCharacter(char16_t aReplacementCharacter); protected: bool AppendToBuffer(nsScannerString::Buffer *, nsIRequest *aRequest, int32_t aErrorPos = -1); bool AppendToBuffer(const nsAString& aStr) { nsScannerString::Buffer* buf = nsScannerString::AllocBufferFromString(aStr); if (!buf) return false; AppendToBuffer(buf, nullptr); return true; } nsScannerString* mSlidingBuffer; nsScannerIterator mCurrentPosition; // The position we will next read from in the scanner buffer nsScannerIterator mMarkPosition; // The position last marked (we may rewind to here) nsScannerIterator mEndPosition; // The current end of the scanner buffer nsScannerIterator mFirstInvalidPosition; // The position of the first invalid character that was detected nsString mFilename; uint32_t mCountRemaining; // The number of bytes still to be read // from the scanner buffer bool mIncremental; bool mHasInvalidCharacter; char16_t mReplacementCharacter; int32_t mFirstNonWhitespacePosition; int32_t mCharsetSource; nsCString mCharset; nsCOMPtr mUnicodeDecoder; private: nsScanner &operator =(const nsScanner &); // Not implemented. }; #endif