1 /* $NetBSD: humanize_number.c,v 1.8 2004/07/27 01:56:24 enami Exp $ */
2
3 /*
4 * Copyright (c) 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
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.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
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.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the NetBSD
22 * Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 * contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40 #include <sys/cdefs.h>
41
42 #include <sys/types.h>
43 #include <assert.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <locale.h>
48 #include <stdint.h>
49 #include <limits.h>
50 #include <unistd.h>
51 #include <stdbool.h>
52
53 /* humanize_number(3) */
54 #define HN_DECIMAL 0x01
55 #define HN_NOSPACE 0x02
56 #define HN_B 0x04
57 #define HN_DIVISOR_1000 0x08
58
59 #define HN_GETSCALE 0x10
60 #define HN_AUTOSCALE 0x20
61
62 static int
xo_humanize_number(char * buf,size_t len,int64_t bytes,const char * suffix,int scale,int flags)63 xo_humanize_number (char *buf, size_t len, int64_t bytes,
64 const char *suffix, int scale, int flags)
65 {
66 const char *prefixes, *sep;
67 int b, i, r, maxscale, s1, s2, sign;
68 int64_t divisor, max;
69 // We multiply bytes by 100 to deal with rounding, so we need something
70 // big enough to hold LLONG_MAX * 100. On 64-bit we can use 128-bit wide
71 // integers with __int128_t, but on 32-bit we have to use long double.
72 #ifdef __LP64__
73 __int128_t scalable = (__int128_t)bytes;
74 #else
75 long double scalable = (long double)bytes;
76 #endif
77 size_t baselen;
78
79 assert(buf != NULL);
80 assert(suffix != NULL);
81 assert(scale >= 0);
82
83 if (flags & HN_DIVISOR_1000) {
84 /* SI for decimal multiplies */
85 divisor = 1000;
86 if (flags & HN_B)
87 prefixes = "B\0k\0M\0G\0T\0P\0E";
88 else
89 prefixes = "\0\0k\0M\0G\0T\0P\0E";
90 } else {
91 /*
92 * binary multiplies
93 * XXX IEC 60027-2 recommends Ki, Mi, Gi...
94 */
95 divisor = 1024;
96 if (flags & HN_B)
97 prefixes = "B\0K\0M\0G\0T\0P\0E";
98 else
99 prefixes = "\0\0K\0M\0G\0T\0P\0E";
100 }
101
102 #define SCALE2PREFIX(scale) (&prefixes[(scale) << 1])
103 maxscale = 7;
104
105 if (scale >= maxscale &&
106 (scale & (HN_AUTOSCALE | HN_GETSCALE)) == 0)
107 return (-1);
108
109 if (buf == NULL || suffix == NULL)
110 return (-1);
111
112 if (len > 0)
113 buf[0] = '\0';
114 if (bytes < 0) {
115 sign = -1;
116 scalable *= -100;
117 baselen = 3; /* sign, digit, prefix */
118 } else {
119 sign = 1;
120 scalable *= 100;
121 baselen = 2; /* digit, prefix */
122 }
123 if (flags & HN_NOSPACE)
124 sep = "";
125 else {
126 sep = " ";
127 baselen++;
128 }
129 baselen += strlen(suffix);
130
131 /* Check if enough room for `x y' + suffix + `\0' */
132 if (len < baselen + 1)
133 return (-1);
134
135 if (scale & (HN_AUTOSCALE | HN_GETSCALE)) {
136 /* See if there is additional columns can be used. */
137 for (max = 100, i = len - baselen; i-- > 0;)
138 max *= 10;
139
140 for (i = 0; scalable >= max && i < maxscale; i++)
141 scalable /= divisor;
142
143 if (scale & HN_GETSCALE)
144 return (i);
145 } else
146 for (i = 0; i < scale && i < maxscale; i++)
147 scalable /= divisor;
148
149 /* If a value <= 9.9 after rounding and ... */
150 if (scalable < 995 && i > 0 && flags & HN_DECIMAL) {
151 /* baselen + \0 + .N */
152 if (len < baselen + 1 + 2)
153 return (-1);
154 b = ((int)scalable + 5) / 10;
155 s1 = b / 10;
156 s2 = b % 10;
157 r = snprintf(buf, len, "%s%d%s%d%s%s%s",
158 ((sign == -1) ? "-" : ""),
159 s1, localeconv()->decimal_point, s2,
160 sep, SCALE2PREFIX(i), suffix);
161 } else
162 r = snprintf(buf, len, "%s%lld%s%s%s",
163 /* LONGLONG */
164 ((sign == -1) ? "-" : ""),
165 (long long)((scalable + 50) / 100),
166 sep, SCALE2PREFIX(i), suffix);
167
168 return (r);
169 }
170