javacc-7.0.3.classes.templates.cpp.CharStream.h.template Maven / Gradle / Ivy
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JavaCC is a parser/scanner generator for java.
\#ifndef JAVACC_CHARSTREAM_H_
\#define JAVACC_CHARSTREAM_H_
\#include "JavaCC.h"
\#ifndef INITIAL_BUFFER_SIZE
\#define INITIAL_BUFFER_SIZE 4096
\#endif
#if NAMESPACE
namespace ${NAMESPACE_OPEN}
#fi
/**
* This class describes a character stream that maintains line and
* column number positions of the characters. It also has the capability
* to backup the stream to some extent. An implementation of this
* class is used in the TokenManager implementation generated by
* JavaCCParser.
*
* All the methods except backup can be implemented in any fashion. backup
* needs to be implemented correctly for the correct operation of the lexer.
* Rest of the methods are all used to get information like line number,
* column number and the string that constitutes a token and are not used
* by the lexer. Hence their implementation won't affect the generated lexer's
* operation.
*/
class CharStream {
public:
void setTabSize(int i) { tabSize = i; }
int getTabSize(int i) { return tabSize; }
#if KEEP_LINE_COLUMN
private:
int getBufcolumn(int pos) {
if (trackLineColumn && pos>=0) {
return bufcolumn[pos];
} else {
return -1;
}
}
int getBufline(int pos) {
if (trackLineColumn && pos>=0) {
return bufline[pos];
} else {
return -1;
}
}
public:
virtual int getColumn() { return getBufcolumn(bufpos); }
virtual int getLine() { return getBufline(bufpos); }
virtual int getEndColumn() { return getBufcolumn(bufpos); }
virtual int getEndLine() { return getBufline(bufpos); }
virtual int getBeginColumn() { return getBufcolumn(tokenBegin); }
virtual int getBeginLine() { return getBufline(tokenBegin); }
#else
virtual int getColumn() { return -1; }
virtual int getLine() { return -1; }
virtual int getEndColumn() { return -1; }
virtual int getEndLine() { return -1; }
virtual int getBeginColumn() { return -1; }
virtual int getBeginLine() { return -1; }
#fi
virtual bool getTrackLineColumn() { return trackLineColumn; }
virtual void setTrackLineColumn(bool val) { trackLineColumn = val; }
/**
* Backs up the input stream by amount steps. Lexer calls this method if it
* had already read some characters, but could not use them to match a
* (longer) token. So, they will be used again as the prefix of the next
* token and it is the implemetation's responsibility to do this right.
*/
virtual inline void backup(int amount) {
inBuf += amount;
bufpos -= amount;
if (bufpos < 0) {
bufpos += bufsize;
}
}
/**
* Returns the next character that marks the beginning of the next token.
* All characters must remain in the buffer between two successive calls
* to this method to implement backup correctly.
*/
virtual inline JJChar BeginToken() {
tokenBegin = -1;
JJChar c = readChar();
tokenBegin = bufpos;
return c;
}
/**
* Returns the next character from the selected input. The method
* of selecting the input is the responsibility of the class
* implementing this class.
*/
virtual inline JJChar readChar() {
if (inBuf > 0) {
--inBuf;
++bufpos;
if (bufpos == bufsize) {
bufpos = 0;
}
return buffer[bufpos];
}
++bufpos;
if (bufpos >= maxNextCharInd) {
FillBuff();
}
JJChar c = buffer[bufpos];
#if KEEP_LINE_COLUMN
if (trackLineColumn) {
UpdateLineColumn(c);
}
#fi
return c;
}
virtual void ExpandBuff(bool wrapAround);
virtual void FillBuff();
/**
* Returns a string made up of characters from the marked token beginning
* to the current buffer position. Implementations can return
* anything that they want to. For example, for efficiency, one might decide
* to just return NULL, which is a valid implementation.
*/
virtual JJString GetImage() {
if (bufpos >= tokenBegin)
return JJString(buffer + tokenBegin, bufpos - tokenBegin + 1);
else
return JJString(buffer + tokenBegin, bufsize - tokenBegin).append(buffer, bufpos + 1);
}
/**
* Returns an array of characters that make up the suffix of length 'len' for
* the currently matched token. This is used to build up the matched string
* for use in actions in the case of MORE. A simple and inefficient
* implementation of this is as follows :
*/
virtual JJString GetSuffix(int len) {
if ((bufpos + 1) >= len) {
return JJString(buffer + bufpos - len + 1, len);
}
return JJString(buffer + bufsize - (len - bufpos - 1), len - bufpos - 1).append(buffer, bufpos + 1);
}
/**
* The lexer calls this function to indicate that it is done with the stream
* and hence implementations can free any resources held by this class.
*/
virtual void DeleteBuffers();
virtual ~CharStream() {
if (deleteStream) {
delete inputStream;
}
DeleteBuffers();
}
bool endOfInput() {
return inBuf == 0 && bufpos + 1 >= maxNextCharInd && inputStream->endOfInput();
}
CharStream(const JJChar *buf, int sz, int startline,
int startcolumn, int buffersize) :
bufline(nullptr), bufcolumn(nullptr), buffer(nullptr), bufpos(0), bufsize(0),
tokenBegin(0), column(0), line(0), prevCharIsCR(false), prevCharIsLF(false),
available(0), maxNextCharInd(0), inBuf(0), tabSize(1), trackLineColumn(true),
inputStream(nullptr), deleteStream(false) {
ReInit(JJString(buf, sz), startline, startcolumn, buffersize);
}
CharStream(const JJChar *buf, int sz, int startline, int startcolumn) :
bufline(nullptr), bufcolumn(nullptr), buffer(nullptr), bufpos(0), bufsize(0),
tokenBegin(0), column(0), line(0), prevCharIsCR(false), prevCharIsLF(false),
available(0), maxNextCharInd(0), inBuf(0), tabSize(1), trackLineColumn(true),
inputStream(nullptr), deleteStream(false) {
ReInit(JJString(buf, sz), startline, startcolumn, INITIAL_BUFFER_SIZE);
}
CharStream(const JJString& str, int startline,
int startcolumn, int buffersize) :
bufline(nullptr), bufcolumn(nullptr), buffer(nullptr), bufpos(0), bufsize(0),
tokenBegin(0), column(0), line(0), prevCharIsCR(false), prevCharIsLF(false),
available(0), maxNextCharInd(0), inBuf(0), tabSize(1), trackLineColumn(true),
inputStream(nullptr), deleteStream(false) {
ReInit(str, startline, startcolumn, buffersize);
}
CharStream(const JJString& str, int startline, int startcolumn) :
bufline(nullptr), bufcolumn(nullptr), buffer(nullptr), bufpos(0), bufsize(0),
tokenBegin(0), column(0), line(0), prevCharIsCR(false), prevCharIsLF(false),
available(0), maxNextCharInd(0), inBuf(0), tabSize(1), trackLineColumn(true),
inputStream(nullptr), deleteStream(false) {
ReInit(str, startline, startcolumn, INITIAL_BUFFER_SIZE);
}
CharStream(ReaderStream *input_stream, int startline,
int startcolumn, int buffersize) :
bufline(nullptr), bufcolumn(nullptr), buffer(nullptr), bufpos(0), bufsize(0),
tokenBegin(0), column(0), line(0), prevCharIsCR(false), prevCharIsLF(false),
available(0), maxNextCharInd(0), inBuf(0), tabSize(1), trackLineColumn(true),
inputStream(nullptr), deleteStream(false) {
ReInit(input_stream, startline, startcolumn, INITIAL_BUFFER_SIZE);
}
CharStream(ReaderStream *input_stream, int startline, int startcolumn) :
bufline(nullptr), bufcolumn(nullptr), buffer(nullptr), bufpos(0), bufsize(0),
tokenBegin(0), column(0), line(0), prevCharIsCR(false), prevCharIsLF(false),
available(0), maxNextCharInd(0), inBuf(0), tabSize(1), trackLineColumn(true),
inputStream(nullptr), deleteStream(false) {
ReInit(input_stream, startline, startcolumn, INITIAL_BUFFER_SIZE);
}
CharStream(ReaderStream *input_stream) :
bufline(nullptr), bufcolumn(nullptr), buffer(nullptr), bufpos(0), bufsize(0),
tokenBegin(0), column(0), line(0), prevCharIsCR(false), prevCharIsLF(false),
available(0), maxNextCharInd(0), inBuf(0), tabSize(1), trackLineColumn(true),
inputStream(nullptr), deleteStream(false) {
ReInit(input_stream, 1, 1, INITIAL_BUFFER_SIZE);
}
virtual void ReInit(ReaderStream *input_stream, int startline, int startcolumn, int buffersize);
virtual void ReInit(ReaderStream *input_stream, int startline, int startcolumn) {
ReInit(input_stream, startline, startcolumn, INITIAL_BUFFER_SIZE);
}
virtual void ReInit(ReaderStream *input_stream) {
ReInit(input_stream, 1, 1, INITIAL_BUFFER_SIZE);
}
virtual void ReInit(const JJString& str, int startline,
int startcolumn, int buffersize);
virtual void ReInit(const JJString& str, int startline,
int startcolumn) {
ReInit(str, startline, startcolumn, INITIAL_BUFFER_SIZE);
}
virtual void adjustBeginLineColumn(int newLine, int newCol);
protected:
virtual void UpdateLineColumn(JJChar c);
int* bufline;
int* bufcolumn;
JJChar* buffer;
int bufpos;
int bufsize;
int tokenBegin;
int column;
int line;
bool prevCharIsCR;
bool prevCharIsLF;
int available;
int maxNextCharInd;
int inBuf;
int tabSize;
bool trackLineColumn;
ReaderStream* inputStream;
bool deleteStream;
};
#if NAMESPACE
${NAMESPACE_CLOSE}
#fi
\#endif
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