1 /* $NetBSD: humanize_number.c,v 1.14 2008/04/28 20:22:59 martin Exp $ */
4 * Copyright (c) 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc.
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center, by Luke Mewburn and by Tomas Svensson.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
36 #include <sys/types.h>
46 humanize_number(char *buf, size_t len, int64_t quotient,
47 const char *suffix, int scale, int flags)
49 const char *prefixes, *sep;
50 int i, r, remainder, maxscale, s1, s2, sign;
55 assert(suffix != NULL);
60 if (flags & HN_DIVISOR_1000) {
61 /* SI for decimal multiplies */
64 prefixes = "B\0k\0M\0G\0T\0P\0E";
66 prefixes = "\0\0k\0M\0G\0T\0P\0E";
70 * XXX IEC 60027-2 recommends Ki, Mi, Gi...
74 prefixes = "B\0K\0M\0G\0T\0P\0E";
76 prefixes = "\0\0K\0M\0G\0T\0P\0E";
79 #define SCALE2PREFIX(scale) (&prefixes[(scale) << 1])
82 if (scale >= maxscale &&
83 (scale & (HN_AUTOSCALE | HN_GETSCALE)) == 0)
86 if (buf == NULL || suffix == NULL)
94 baselen = 3; /* sign, digit, prefix */
97 baselen = 2; /* digit, prefix */
99 if (flags & HN_NOSPACE)
105 baselen += strlen(suffix);
107 /* Check if enough room for `x y' + suffix + `\0' */
108 if (len < baselen + 1)
111 if (scale & (HN_AUTOSCALE | HN_GETSCALE)) {
112 /* See if there is additional columns can be used. */
113 for (max = 1, i = len - baselen; i-- > 0;)
117 * Divide the number until it fits the given column.
118 * If there will be an overflow by the rounding below,
122 (quotient >= max || (quotient == max - 1 && remainder >= 950)) &&
124 remainder = quotient % divisor;
128 if (scale & HN_GETSCALE)
131 for (i = 0; i < scale && i < maxscale; i++) {
132 remainder = quotient % divisor;
137 /* If a value <= 9.9 after rounding and ... */
138 if (quotient <= 9 && remainder < 950 && i > 0 && flags & HN_DECIMAL) {
139 /* baselen + \0 + .N */
140 if (len < baselen + 1 + 2)
142 s1 = (int)quotient + ((remainder + 50) / 1000);
143 s2 = ((remainder + 50) / 100) % 10;
144 r = snprintf(buf, len, "%d%s%d%s%s%s",
145 sign * s1, localeconv()->decimal_point, s2,
146 sep, SCALE2PREFIX(i), suffix);
148 r = snprintf(buf, len, "%" PRId64 "%s%s%s",
149 sign * (quotient + (remainder + 50) / 1000),
150 sep, SCALE2PREFIX(i), suffix);