javacc-7.0.3.bin.templates.cpp.CharStream.h.template Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of javacc Show documentation
Show all versions of javacc Show documentation
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
© 2015 - 2024 Weber Informatics LLC | Privacy Policy