gecko-dev/parser/htmlparser/nsScanner.h

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/* -*- 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 "mozilla/Encoding.h"
#include "nsScannerString.h"
#include "mozilla/CheckedInt.h"
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 final {
using Encoding = mozilla::Encoding;
template <typename T>
using NotNull = mozilla::NotNull<T>;
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);
/**
* 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);
/**
* 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(NotNull<const Encoding*> aEncoding,
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);
/**
* 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; }
protected:
bool AppendToBuffer(nsScannerString::Buffer* aBuffer);
bool AppendToBuffer(const nsAString& aStr) {
nsScannerString::Buffer* buf = nsScannerString::AllocBufferFromString(aStr);
if (!buf) return false;
AppendToBuffer(buf);
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
nsString mFilename;
bool mIncremental;
int32_t mCharsetSource;
nsCString mCharset;
mozilla::UniquePtr<mozilla::Decoder> mUnicodeDecoder;
private:
nsScanner& operator=(const nsScanner&); // Not implemented.
};
#endif