1 /* $NetBSD: humanize_number.c,v 1.16 2012/03/17 20:01:14 christos 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 #if defined(LIBC_SCCS) && !defined(lint)
35 __RCSID("$NetBSD: humanize_number.c,v 1.16 2012/03/17 20:01:14 christos Exp $");
36 #endif /* LIBC_SCCS and not lint */
38 #include "namespace.h"
47 humanize_number(char *buf
, size_t len
, int64_t bytes
,
48 const char *suffix
, int scale
, int flags
)
50 const char *prefixes
, *sep
;
51 int b
, r
, s1
, s2
, sign
;
52 int64_t divisor
, max
, post
= 1;
53 size_t i
, baselen
, maxscale
;
55 _DIAGASSERT(buf
!= NULL
);
56 _DIAGASSERT(suffix
!= NULL
);
57 _DIAGASSERT(scale
>= 0);
59 if (flags
& HN_DIVISOR_1000
) {
60 /* SI for decimal multiplies */
63 prefixes
= "B\0k\0M\0G\0T\0P\0E";
65 prefixes
= "\0\0k\0M\0G\0T\0P\0E";
69 * XXX IEC 60027-2 recommends Ki, Mi, Gi...
73 prefixes
= "B\0K\0M\0G\0T\0P\0E";
75 prefixes
= "\0\0K\0M\0G\0T\0P\0E";
78 #define SCALE2PREFIX(scale) (&prefixes[(scale) << 1])
81 if ((size_t)scale
>= maxscale
&&
82 (scale
& (HN_AUTOSCALE
| HN_GETSCALE
)) == 0)
85 if (buf
== NULL
|| suffix
== NULL
)
92 baselen
= 3; /* sign, digit, prefix */
93 if (-bytes
< INT64_MAX
/ 100)
102 baselen
= 2; /* digit, prefix */
103 if (bytes
< INT64_MAX
/ 100)
110 if (flags
& HN_NOSPACE
)
116 baselen
+= strlen(suffix
);
118 /* Check if enough room for `x y' + suffix + `\0' */
119 if (len
< baselen
+ 1)
122 if (scale
& (HN_AUTOSCALE
| HN_GETSCALE
)) {
123 /* See if there is additional columns can be used. */
124 for (max
= 100, i
= len
- baselen
; i
-- > 0;)
128 * Divide the number until it fits the given column.
129 * If there will be an overflow by the rounding below,
132 for (i
= 0; bytes
>= max
- 50 && i
< maxscale
; i
++)
135 if (scale
& HN_GETSCALE
) {
136 _DIAGASSERT(__type_fit(int, i
));
140 for (i
= 0; i
< (size_t)scale
&& i
< maxscale
; i
++)
144 /* If a value <= 9.9 after rounding and ... */
145 if (bytes
< 995 && i
> 0 && flags
& HN_DECIMAL
) {
146 /* baselen + \0 + .N */
147 if (len
< baselen
+ 1 + 2)
149 b
= ((int)bytes
+ 5) / 10;
152 r
= snprintf(buf
, len
, "%d%s%d%s%s%s",
153 sign
* s1
, localeconv()->decimal_point
, s2
,
154 sep
, SCALE2PREFIX(i
), suffix
);
156 r
= snprintf(buf
, len
, "%" PRId64
"%s%s%s",
157 sign
* ((bytes
+ 50) / 100),
158 sep
, SCALE2PREFIX(i
), suffix
);