/* $NetBSD: humanize_number.c,v 1.14 2008/04/28 20:22:59 martin Exp $ */
/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc.
* Copyright 2013 John-Mark Gurney <jmg@FreeBSD.org>
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center, by Luke Mewburn and by Tomas Svensson.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#include <sys/types.h>
#include <assert.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <locale.h>
#include <libutil.h>
static const int maxscale = 6;
int
humanize_number(char *buf, size_t len, int64_t quotient,
const char *suffix, int scale, int flags)
{
const char *prefixes, *sep;
int i, r, remainder, s1, s2, sign;
int divisordeccut;
int64_t divisor, max;
size_t baselen;
/* Since so many callers don't check -1, NUL terminate the buffer */
if (len > 0)
buf[0] = '\0';
/* validate args */
if (buf == NULL || suffix == NULL)
return (-1);
if (scale < 0)
return (-1);
else if (scale > maxscale &&
((scale & ~(HN_AUTOSCALE|HN_GETSCALE)) != 0))
return (-1);
if ((flags & HN_DIVISOR_1000) && (flags & HN_IEC_PREFIXES))
return (-1);
/* setup parameters */
remainder = 0;
if (flags & HN_IEC_PREFIXES) {
baselen = 2;
/*
* Use the prefixes for power of two recommended by
* the International Electrotechnical Commission
* (IEC) in IEC 80000-3 (i.e. Ki, Mi, Gi...).
*
* HN_IEC_PREFIXES implies a divisor of 1024 here
* (use of HN_DIVISOR_1000 would have triggered
* an assertion earlier).
*/
divisor = 1024;
divisordeccut = 973; /* ceil(.95 * 1024) */
if (flags & HN_B)
prefixes = "B\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei";
else
prefixes = "\0\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei";
} else {
baselen = 1;
if (flags & HN_DIVISOR_1000) {
divisor = 1000;
divisordeccut = 950;
if (flags & HN_B)
prefixes = "B\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E";
else
prefixes = "\0\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E";
} else {
divisor = 1024;
divisordeccut = 973; /* ceil(.95 * 1024) */
if (flags & HN_B)
prefixes = "B\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E";
else
prefixes = "\0\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E";
}
}
#define SCALE2PREFIX(scale) (&prefixes[(scale) * 3])
if (quotient < 0) {
sign = -1;
quotient = -quotient;
baselen += 2; /* sign, digit */
} else {
sign = 1;
baselen += 1; /* digit */
}
if (flags & HN_NOSPACE)
sep = "";
else {
sep = " ";
baselen++;
}
baselen += strlen(suffix);
/* Check if enough room for `x y' + suffix + `\0' */
if (len < baselen + 1)
return (-1);
if (scale & (HN_AUTOSCALE | HN_GETSCALE)) {
/* See if there is additional columns can be used. */
for (max = 1, i = len - baselen; i-- > 0;)
max *= 10;
/*
* Divide the number until it fits the given column.
* If there will be an overflow by the rounding below,
* divide once more.
*/
for (i = 0;
(quotient >= max || (quotient == max - 1 &&
(remainder >= divisordeccut || remainder >=
divisor / 2))) && i < maxscale; i++) {
remainder = quotient % divisor;
quotient /= divisor;
}
if (scale & HN_GETSCALE)
return (i);
} else {
for (i = 0; i < scale && i < maxscale; i++) {
remainder = quotient % divisor;
quotient /= divisor;
}
}
/* If a value <= 9.9 after rounding and ... */
/*
* XXX - should we make sure there is enough space for the decimal
* place and if not, don't do HN_DECIMAL?
*/
if (((quotient == 9 && remainder < divisordeccut) || quotient < 9) &&
i > 0 && flags & HN_DECIMAL) {
s1 = (int)quotient + ((remainder * 10 + divisor / 2) /
divisor / 10);
s2 = ((remainder * 10 + divisor / 2) / divisor) % 10;
r = snprintf(buf, len, "%d%s%d%s%s%s",
sign * s1, localeconv()->decimal_point, s2,
sep, SCALE2PREFIX(i), suffix);
} else
r = snprintf(buf, len, "%" PRId64 "%s%s%s",
sign * (quotient + (remainder + divisor / 2) / divisor),
sep, SCALE2PREFIX(i), suffix);
return (r);
}
plain