/***********************************************************************

*                                                                      *

*               This software is part of the ast package               *

*          Copyright (c) 1985-2011 AT&T Intellectual Property          *

*                      and is licensed under the                       *

*                 Eclipse Public License, Version 1.0                  *

*                    by AT&T Intellectual Property                     *

*                                                                      *

*                A copy of the License is available at                 *

*          http://www.eclipse.org/org/documents/epl-v10.html           *

*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *

*                                                                      *

*              Information and Software Systems Research               *

*                            AT&T Research                             *

*                           Florham Park NJ                            *

*                                                                      *

*                 Glenn Fowler <gsf@research.att.com>                  *

*                  David Korn <dgk@research.att.com>                   *

*                   Phong Vo <kpv@research.att.com>                    *

*                                                                      *

***********************************************************************/

#pragma prototyped

/*

 * Glenn Fowler

 * AT&T Research

 *

 * return number n scaled to metric multiples of k { 1000 1024 }

 * return string length is at most 5 chars + terminating nul

 */

#include <ast.h>

#include <lclib.h>

char*

fmtscale(register Sfulong_t n, int k)

{

	register Sfulong_t	m;

	int			r;

	int			z;

	const char*		u;

	char			suf[3];

	char*			s;

	char*			buf;

	Lc_numeric_t*		p = (Lc_numeric_t*)LCINFO(AST_LC_NUMERIC)->data;

	static const char	scale[] = "bkMGTPE";

	u = scale;

	if (n < 1000)

		r = 0;

	else

	{

		m = 0;

		while (n >= k && *(u + 1))

		{

			m = n;

			n /= k;

			u++;

		}

		if ((r = (10 * (m % k) + (k / 2)) / k) > 9)

		{

			r = 0;

			n++;

		}

		if (k == 1024 && n >= 1000)

		{

			n = 1;

			r = 0;

			u++;

		}

	}

	buf = fmtbuf(z = 8);

	s = suf;

	if (u > scale)

	{

		if (k == 1024)

		{

			*s++ = *u == 'k' ? 'K' : *u;

			*s++ = 'i';

		}

		else

			*s++ = *u;

	}

	*s = 0;

	if (n > 0 && n < 10)

		sfsprintf(buf, z, "%I*u%c%d%s", sizeof(n), n, p->decimal >= 0 ? p->decimal : '.', r, suf);

	else

	{

		if (r >= 5)

			n++;

		sfsprintf(buf, z, "%I*u%s", sizeof(n), n, suf);

	}

	return buf;

}