/*
 * fgetc
 * Conforms closely to the standard i/o function used in the Version 7 
 * U**X C Library but takes careful note of the CP/M console and reader
 * devices. The structure of the hypothetical getc macro corresponding
 * to this function is as follows:
 * #define getc(p) ((p)->_nleft-- ? *(p)->_nextp++ : _filbuf(p))
 * Last Edit 7/3/83
 */

int
fgetc(stream)
FILE *stream;
{
	int nsecs;
	char c;
	if (stream == stdin) {
		c = bdos(1,0);
		return ((c == '\r') ? '\n' : c) ;
	}
	else if (stream == DEV_RDR)
		return bdos(3,0);
	else if (!stream -> _nleft--) {
		if((nsecs = read(stream->_fd, stream->_base, NSECTS)) <= 0){
			if (stream -> _nleft == EOF)
				stream -> _flag = _IOEOF ;
			if (nsecs == ERROR)
				stream -> _flag |= _IOERR ;
			return stream -> _nleft++;
		}
		stream -> _nleft = nsecs * SECSIZ - 1;
		stream -> _nextp = stream -> _base;
	}
	return *stream->_nextp++;
}

/*
 * fputc
 * This function conforms closely to the function in the Version
 * 7 U**X C Library with consideraton of the CPM console and reader
 * devices. The hypothetical corresponding putc macro follows:
 * #define putc(c,p) ((p)->_nleft--?*(p)->_nextp++ = (c):_flsbuf((x),p))
 * Last Edit 7/1/83
 */

void
fputc(c,stream)
char c;
FILE *stream;
{
	if (stream==stdout) {
		if (c == '\n')
			bdos(2,'\r');
		bdos(2,c);
		return ;
	}
	else if (stream==DEV_LST) {
		bdos(5,c);
		return ;
	}
	else if (stream==DEV_PUN) {
		bdos(4,c);
		return ;
	}
	else if (stream==stderr) {
		if (c == '\n')
			bios(4,'\r');
		bios(4,c);
		return ;
	}
	if ((stream -> _flag & _IOWRT) == 0) { /* can't write on stream	*/
		stream -> _flag |= _IOERR ;
		return ;
	}
	if (!stream -> _nleft--) {	/* if buffer full then flush it	*/
		if ((write(stream->_fd, stream->_base, NSECTS)) != NSECTS) {
			stream -> _flag |= _IOERR ;
			return ;
		}
		stream -> _nleft = (BUFSIZ - 1);
		stream -> _nextp = stream -> _base;
	}
	*stream -> _nextp++ = c;
	return ;
}

/*
 * ungetc
 * This function conforms closely to the macro used in the Version
 * 7 U**X Standard C Libary. It is a buffered "unget" character
 * routine. Only ONE char may be "ungotten" between consecutive
 * getc()/fgetc() calls. Note that any ungotten character is lost
 * if a call subsquently made to fseek(). The macro corresponding
 * the function is as follows:
 * #define ungetc(c,p) ((p)->_nleft==BUFSIZ ? -1 : *--(p)->_nextp=(c))
 * Last Edit 7/3/83
 */

void
ungetc(c, stream)
FILE *stream;
char c;
{
	if (stream == stdin) {
		ungetch(c);			/* stdin is special	*/
		return ;
	}
	else if (stream <= DEV_PUN && stream > stdin) {
		/* stream -> _flag |= _IOERR ;	 no pushbacks here	*/
		return ;
	}
	if (stream -> _nleft == BUFSIZ) {
		stream -> _flag |= _IOERR ;	/* too many pushed back	*/
		return ;
	}
	*--stream -> _nextp = c ;
	stream -> _nleft++ ;
	return ;
}