/* Copyright (c) 1992 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "@(#)portio.c 2.3 10/2/92 LBL";
#endif

/*
 * Portable i/o for binary files
 */

#include <stdio.h>

#ifndef frexp
extern double  frexp();
#endif
#ifndef ldexp
extern double  ldexp();
#endif


putstr(s, fp)			/* write null-terminated string to fp */
register char  *s;
register FILE  *fp;
{
	do
		putc(*s, fp);
	while (*s++);
}


putint(i, siz, fp)		/* write a siz-byte integer to fp */
long  i;
register int  siz;
register FILE  *fp;
{
	while (siz--)
		putc((int)(i>>(siz<<3) & 0xff), fp);
}


putflt(f, fp)			/* put out floating point number */
double	f;
FILE  *fp;
{
	int  e;

	putint((long)(frexp(f,&e)*0x7fffffff), 4, fp);
	putint((long)e, 1, fp);
}


char *
getstr(s, fp)			/* get null-terminated string */
char  *s;
register FILE  *fp;
{
	register char  *cp;
	register int  c;

	cp = s;
	while ((c = getc(fp)) != EOF)
		if ((*cp++ = c) == '\0')
			return(s);
		
	return(NULL);
}


long
getint(siz, fp)			/* get a siz-byte integer */
int  siz;
register FILE  *fp;
{
	register int  c;
	register long  r;

	if ((c = getc(fp)) == EOF)
		return(EOF);
	r = 0x80&c ? -1<<8|c : c;		/* sign extend */
	while (--siz > 0) {
		if ((c = getc(fp)) == EOF)
			return(EOF);
		r <<= 8;
		r |= c;
	}
	return(r);
}


double
getflt(fp)			/* get a floating point number */
FILE  *fp;
{
	double	d;

	d = (double)getint(4, fp)/0x7fffffff;
	return(ldexp(d, (int)getint(1, fp)));
}