1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26#include <ctype.h>
27#include <math.h>
28#include <stdio.h>
29#include <libzutil.h>
30
31/*
32 * Return B_TRUE if "str" is a number string, B_FALSE otherwise.
33 * Works for integer and floating point numbers.
34 */
35boolean_t
36zfs_isnumber(const char *str)
37{
38	if (!*str)
39		return (B_FALSE);
40
41	for (; *str; str++)
42		if (!(isdigit(*str) || (*str == '.')))
43			return (B_FALSE);
44
45	return (B_TRUE);
46}
47
48/*
49 * Convert a number to an appropriately human-readable output.
50 */
51void
52zfs_nicenum_format(uint64_t num, char *buf, size_t buflen,
53    enum zfs_nicenum_format format)
54{
55	uint64_t n = num;
56	int index = 0;
57	const char *u;
58	const char *units[3][7] = {
59	    [ZFS_NICENUM_1024] = {"", "K", "M", "G", "T", "P", "E"},
60	    [ZFS_NICENUM_BYTES] = {"B", "K", "M", "G", "T", "P", "E"},
61	    [ZFS_NICENUM_TIME] = {"ns", "us", "ms", "s", "?", "?", "?"}
62	};
63
64	const int units_len[] = {[ZFS_NICENUM_1024] = 6,
65	    [ZFS_NICENUM_BYTES] = 6,
66	    [ZFS_NICENUM_TIME] = 4};
67
68	const int k_unit[] = {	[ZFS_NICENUM_1024] = 1024,
69	    [ZFS_NICENUM_BYTES] = 1024,
70	    [ZFS_NICENUM_TIME] = 1000};
71
72	double val;
73
74	if (format == ZFS_NICENUM_RAW) {
75		snprintf(buf, buflen, "%llu", (u_longlong_t)num);
76		return;
77	} else if (format == ZFS_NICENUM_RAWTIME && num > 0) {
78		snprintf(buf, buflen, "%llu", (u_longlong_t)num);
79		return;
80	} else if (format == ZFS_NICENUM_RAWTIME && num == 0) {
81		snprintf(buf, buflen, "%s", "-");
82		return;
83	}
84
85	while (n >= k_unit[format] && index < units_len[format]) {
86		n /= k_unit[format];
87		index++;
88	}
89
90	u = units[format][index];
91
92	/* Don't print zero latencies since they're invalid */
93	if ((format == ZFS_NICENUM_TIME) && (num == 0)) {
94		(void) snprintf(buf, buflen, "-");
95	} else if ((index == 0) || ((num %
96	    (uint64_t)powl(k_unit[format], index)) == 0)) {
97		/*
98		 * If this is an even multiple of the base, always display
99		 * without any decimal precision.
100		 */
101		(void) snprintf(buf, buflen, "%llu%s", (u_longlong_t)n, u);
102
103	} else {
104		/*
105		 * We want to choose a precision that reflects the best choice
106		 * for fitting in 5 characters.  This can get rather tricky when
107		 * we have numbers that are very close to an order of magnitude.
108		 * For example, when displaying 10239 (which is really 9.999K),
109		 * we want only a single place of precision for 10.0K.  We could
110		 * develop some complex heuristics for this, but it's much
111		 * easier just to try each combination in turn.
112		 */
113		int i;
114		for (i = 2; i >= 0; i--) {
115			val = (double)num /
116			    (uint64_t)powl(k_unit[format], index);
117
118			/*
119			 * Don't print floating point values for time.  Note,
120			 * we use floor() instead of round() here, since
121			 * round can result in undesirable results.  For
122			 * example, if "num" is in the range of
123			 * 999500-999999, it will print out "1000us".  This
124			 * doesn't happen if we use floor().
125			 */
126			if (format == ZFS_NICENUM_TIME) {
127				if (snprintf(buf, buflen, "%d%s",
128				    (unsigned int) floor(val), u) <= 5)
129					break;
130
131			} else {
132				if (snprintf(buf, buflen, "%.*f%s", i,
133				    val, u) <= 5)
134					break;
135			}
136		}
137	}
138}
139
140/*
141 * Convert a number to an appropriately human-readable output.
142 */
143void
144zfs_nicenum(uint64_t num, char *buf, size_t buflen)
145{
146	zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_1024);
147}
148
149/*
150 * Convert a time to an appropriately human-readable output.
151 * @num:	Time in nanoseconds
152 */
153void
154zfs_nicetime(uint64_t num, char *buf, size_t buflen)
155{
156	zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_TIME);
157}
158
159/*
160 * Print out a raw number with correct column spacing
161 */
162void
163zfs_niceraw(uint64_t num, char *buf, size_t buflen)
164{
165	zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_RAW);
166}
167
168/*
169 * Convert a number of bytes to an appropriately human-readable output.
170 */
171void
172zfs_nicebytes(uint64_t num, char *buf, size_t buflen)
173{
174	zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_BYTES);
175}
176