kolibrios-fun/contrib/media/updf/include/lispio.h
Serhii Sakhno cd35d38ad2 updf: restore menuetlibc version
git-svn-id: svn://kolibrios.org@8429 a494cfbc-eb01-0410-851d-a64ba20cac60
2020-12-16 18:41:33 +00:00

110 lines
2.8 KiB
C++

/** \file lispio.h
* definitions of pure input output classes.
*/
#ifndef __lispio_h__
#define __lispio_h__
#include "yacasbase.h"
// Hope this forward declaration doesn't screw us over...
class InputDirectories;
class InputStatus : public YacasBase
{
public:
InputStatus() : iFileName("none") , iLineNumber(-1) {};
~InputStatus();
void SetTo(LispChar * aFileName);
void RestoreFrom(InputStatus& aPreviousStatus);
inline LispInt LineNumber();
inline LispChar * FileName();
inline void NextLine();
inline InputStatus(const InputStatus& aOther) : iFileName(aOther.iFileName) , iLineNumber(aOther.iLineNumber)
{
}
inline InputStatus& operator=(const InputStatus& aOther)
{
iFileName = aOther.iFileName;
iLineNumber = aOther.iLineNumber;
return *this;
}
private:
LispChar * iFileName;
LispInt iLineNumber;
};
inline LispInt InputStatus::LineNumber()
{
return iLineNumber;
}
inline LispChar * InputStatus::FileName()
{
return iFileName;
}
inline void InputStatus::NextLine()
{
iLineNumber++;
}
/** \class LispInput : pure abstract class declaring the interface
* that needs to be implemented by a file (something that expressions
* can be read from).
*/
class LispInput : public YacasBase
{
public:
/** Constructor with InputStatus. InputStatus retains the information
* needed when an error occurred, and the file has already been
* closed.
*/
LispInput(InputStatus& aStatus) : iStatus(aStatus) {};
virtual ~LispInput();
/// Return the next character in the file
virtual LispChar Next() = 0;
/** Peek at the next character in the file, without advancing the file
* pointer.
*/
virtual LispChar Peek() = 0;
virtual InputStatus& Status() const {return iStatus;};
/// Check if the file position is past the end of the file.
virtual LispBoolean EndOfStream() = 0;
/** StartPtr returns the start of a buffer, if there is one.
* Implementations of this class can keep the file in memory
* as a whole, and return the start pointer and current position.
* Especially the parsing code requires this, because it can then
* efficiently look up a symbol in the hash table without having to
* first create a buffer to hold the symbol in. If StartPtr is supported,
* the whole file should be in memory for the whole period the file
* is being read.
*/
virtual LispChar * StartPtr() = 0;
virtual LispInt Position() = 0;
virtual void SetPosition(LispInt aPosition) = 0;
protected:
InputStatus& iStatus;
};
/** \class LispOutput : interface an output object should adhere to.
*/
class LispOutput : public YacasBase
{
public:
virtual ~LispOutput();
/// Write out one character.
virtual void PutChar(LispChar aChar) = 0;
public:
void Write(const LispChar * aString);
};
#endif