//Embedded C++ Library
//Copyright (c) Hitachi,Ltd. 1997
//Licensed material of Hitachi,Ltd
//
//  Embeded C++ Library <streambuf> 
//

//====================================================================
//  File:	streambuf
//  Purpose:	Definition of class streambuf
//  Create:     1997.09.20 Rev. 1.0
//====================================================================

#ifndef _STREAMBUF_
#define _STREAMBUF_

#include <ios>
class streambuf {
public:
	virtual ~streambuf(){}
	streambuf *pubsetbuf(char *cptr, streamsize nnum){
		return setbuf(cptr, nnum);
	}
	pos_type pubseekoff(off_type off,ios_base::seekdir way,
				ios_base::openmode which
					=(ios_base::openmode)
					(ios_base::in|ios_base::out)){
		return seekoff(off, way, which);
	}
	pos_type pubseekpos(pos_type sp,
				ios_base::openmode which
					=(ios_base::openmode)
					(ios_base::in|ios_base::out)){
		return seekpos(sp, which);
	}
	int pubsync(){
		return sync();
	}
	streamsize in_avail(){
		return ((gptr()!=0)&&(gptr()<egptr()) ? 
                       egptr()-gptr(): showmanyc());
	}
	int_type snextc() {return ((sbumpc()==eof) ? eof:sgetc());}
	int_type sbumpc();
	int_type sgetc();
	int sgetn(char* cptr, streamsize nnum) {return xsgetn( cptr, nnum);}
	int_type sputbackc(char);
	int sungetc();
	int sputc(char);
	int_type sputn(const char *cptr, streamsize nnum)
		{return xsputn( cptr, nnum);}
	enum {eof=-1};
protected:
	streambuf();
	char *eback() const {return *B_beg_pptr;}
	char *gptr() const {return *B_next_pptr;}
	char *egptr() const {return (*B_next_pptr+(*_B_cnt_ptr));}
	void gbump(int nptr);
	void setg(char *gbeg, char *gnext, char *gend)
		{*B_beg_pptr = gbeg;*B_next_pptr = gnext;B_end_ptr = gend;
			*_B_cnt_ptr=gend-gnext;*_B_len_ptr=gend-gbeg;}
	char *pbase() const {return *B_beg_pptr;}
	char *pptr() const {return *B_next_pptr;}
	char *epptr() const {return (*B_beg_pptr+(*_B_len_ptr));}
	char *_ec2p_getflag() const { return ((char*)C_flg_ptr);}
	void pbump(int nptr);
	void setp(char *pbeg, char *pend)
		{*B_beg_pptr = pbeg;*B_next_pptr = pbeg;B_end_ptr = pend;
			*_B_cnt_ptr=pend-pbeg;*_B_len_ptr=pend-pbeg;}
	virtual streambuf *setbuf(char *, streamsize){ return this; }
	virtual pos_type seekoff(off_type, ios_base::seekdir,
        		ios_base::openmode=(ios_base::openmode)
			(ios_base::in|ios_base::out)){ return -1; }
	virtual pos_type seekpos(pos_type, ios_base::openmode=
			(ios_base::openmode)(ios_base::in|ios_base::out)){
			return -1; }
	virtual int sync(){ return 0; }
	virtual int showmanyc(){ return 0; }
	virtual streamsize xsgetn(char *, streamsize);
	virtual int_type underflow(){ return eof; }
	virtual int_type uflow();
	virtual int_type pbackfail(int_type=eof){ return eof; }
	virtual streamsize xsputn(const char *, streamsize);
	virtual int_type overflow(int_type=eof){ return eof; }
	char *& _ec2p_gnptr(){ return (char *&)*B_next_pptr;}
	char *& _ec2p_pnptr(){ return (char *&)*B_next_pptr;}
	void _ec2p_bcntplus(){(*_B_cnt_ptr)++;}
	void _ec2p_bcntminus(){(*_B_cnt_ptr)--;}
	void _ec2p_setbPtr(char**, char**, long*, long*,char*);
private:
	long *_B_cnt_ptr, *_B_len_ptr;
	char *B_beg_ptr, *B_next_ptr, *B_end_ptr;
	char **B_beg_pptr, **B_next_pptr;
	char *C_flg_ptr;
};

#endif