/*
	e screen editor

	(C) G. Nigel Gilbert, MICROLOGY, 1981

	August-December 1981

	FILE: e10

	FUNCTIONS: fopen,fcreat,fflush,fclose,putc,getc,funlink,
			frename,dskcheck,err1,err2,err3,err4

	PURPOSE: file buffer operations extracted and stripped from stdlib1,
		with protection from bdos error crashes added

*/

#include "e.h"

int fopen(filename,iobuf)
struct iobuffer *iobuf;
char *filename;
{
	if (dskcheck(setjmp(dskerr)) || (iobuf -> _fd = open(filename,0))<0) return FAIL;
	iobuf -> _nleft = 0;
	return iobuf -> _fd;
}

int fcreat(name,iobuf)
char *name;
struct iobuffer *iobuf;
{
	if (dskcheck(setjmp(dskerr)) || (iobuf -> _fd = creat(name)) < 0 ) return FAIL;
	iobuf -> _nextp = iobuf -> _buff;
	iobuf -> _nleft = (NSECTS * SECSIZ);
	return iobuf -> _fd;
}

int fflush(iobuf)	/*does NOT allow more writing*/
struct iobuffer *iobuf;
{
	int i;

	if (iobuf -> _nleft == (NSECTS * SECSIZ)) return YES;

	i = NSECTS - iobuf->_nleft / SECSIZ;
	if (dskcheck(setjmp(dskerr)) || write(iobuf -> _fd, iobuf -> _buff, i) != i) return FAIL;
	return YES;
}

int fclose(iobuf)
struct iobuffer *iobuf;
{
	if (dskcheck(setjmp(dskerr))) return FAIL;
	return close(iobuf -> _fd);
}

putc(c,iobuf)	/*stripped down version of standard putc*/
char c;
struct iobuffer *iobuf;
{
	if (iobuf -> _nleft--) return *iobuf -> _nextp++ = c;
	if (dskcheck(setjmp(dskerr)) || (write(iobuf -> _fd, iobuf -> _buff, NSECTS)) != NSECTS) return FAIL;
	iobuf -> _nleft = (NSECTS * SECSIZ -1);
	iobuf -> _nextp = iobuf -> _buff;
	return *iobuf -> _nextp++ = c;
}

int getc(iobuf)	/*the standard getc, trimmed for speed*/
struct iobuffer  *iobuf;
{
	int nsecs;

	if (iobuf -> _nleft--) return *iobuf -> _nextp++;
	if (dskcheck(setjmp(dskerr)) || (nsecs = read(iobuf -> _fd, iobuf -> _buff, NSECTS)) <= 0)
		return iobuf -> _nleft++;
	iobuf -> _nleft = nsecs * SECSIZ - 1;
	iobuf -> _nextp = iobuf -> _buff;
	return *iobuf->_nextp++;
}

funlink(name)
char *name;
{
	if (dskcheck(setjmp(dskerr))) return FAIL;
	return unlink(name);
}

frename(oldname,newname)
char *oldname,*newname;
{
	if (dskcheck(setjmp(dskerr))) return FAIL;
	return rename(oldname,newname);
}

dskcheck(errtype)
int errtype;
{
	switch(errtype) {
	case 0: 
		return 0;
	case 1: 
		error("Bad sector"); 
		break;
	case 2: 
		error("Bad disk select"); 
		break;
	case 3: 
		error("Disk is read only"); 
		break;
	case 4: 
		error("File is read only"); 
		break;
		}
	bdos(RESETDSK);
	bdos(SELDSK,curdsk);
	return FAIL;
}

err1()
{
	longjmp(dskerr,1);
}

err2()
{
	longjmp(dskerr,2);
}


err3()
{
	longjmp(dskerr,3);
}

err4()
{
	longjmp(dskerr,4);
}
me)) < 0 ) return FAIL;
	iobuf -> _nextp = iobuf -> _buff;
	iobuf -> _nleft = (NSECT