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 */
35 boolean_t
zfs_isnumber(const char * str)36 zfs_isnumber(const char *str)
37 {
38 for (; *str; str++)
39 if (!(isdigit(*str) || (*str == '.')))
40 return (B_FALSE);
41
42 return (B_TRUE);
43 }
44
45 /*
46 * Convert a number to an appropriately human-readable output.
47 */
48 void
zfs_nicenum_format(uint64_t num,char * buf,size_t buflen,enum zfs_nicenum_format format)49 zfs_nicenum_format(uint64_t num, char *buf, size_t buflen,
50 enum zfs_nicenum_format format)
51 {
52 uint64_t n = num;
53 int index = 0;
54 const char *u;
55 const char *units[3][7] = {
56 [ZFS_NICENUM_1024] = {"", "K", "M", "G", "T", "P", "E"},
57 [ZFS_NICENUM_BYTES] = {"B", "K", "M", "G", "T", "P", "E"},
58 [ZFS_NICENUM_TIME] = {"ns", "us", "ms", "s", "?", "?", "?"}
59 };
60
61 const int units_len[] = {[ZFS_NICENUM_1024] = 6,
62 [ZFS_NICENUM_BYTES] = 6,
63 [ZFS_NICENUM_TIME] = 4};
64
65 const int k_unit[] = { [ZFS_NICENUM_1024] = 1024,
66 [ZFS_NICENUM_BYTES] = 1024,
67 [ZFS_NICENUM_TIME] = 1000};
68
69 double val;
70
71 if (format == ZFS_NICENUM_RAW) {
72 (void) snprintf(buf, buflen, "%llu", (u_longlong_t)num);
73 return;
74 } else if (format == ZFS_NICENUM_RAWTIME && num > 0) {
75 (void) snprintf(buf, buflen, "%llu", (u_longlong_t)num);
76 return;
77 } else if (format == ZFS_NICENUM_RAWTIME && num == 0) {
78 (void) snprintf(buf, buflen, "%s", "-");
79 return;
80 }
81
82 while (n >= k_unit[format] && index < units_len[format]) {
83 n /= k_unit[format];
84 index++;
85 }
86
87 u = units[format][index];
88
89 /* Don't print zero latencies since they're invalid */
90 if ((format == ZFS_NICENUM_TIME) && (num == 0)) {
91 (void) snprintf(buf, buflen, "-");
92 } else if ((index == 0) || ((num %
93 (uint64_t)powl(k_unit[format], index)) == 0)) {
94 /*
95 * If this is an even multiple of the base, always display
96 * without any decimal precision.
97 */
98 (void) snprintf(buf, buflen, "%llu%s", (u_longlong_t)n, u);
99
100 } else {
101 /*
102 * We want to choose a precision that reflects the best choice
103 * for fitting in 5 characters. This can get rather tricky when
104 * we have numbers that are very close to an order of magnitude.
105 * For example, when displaying 10239 (which is really 9.999K),
106 * we want only a single place of precision for 10.0K. We could
107 * develop some complex heuristics for this, but it's much
108 * easier just to try each combination in turn.
109 */
110 int i;
111 for (i = 2; i >= 0; i--) {
112 val = (double)num /
113 (uint64_t)powl(k_unit[format], index);
114
115 /*
116 * Don't print floating point values for time. Note,
117 * we use floor() instead of round() here, since
118 * round can result in undesirable results. For
119 * example, if "num" is in the range of
120 * 999500-999999, it will print out "1000us". This
121 * doesn't happen if we use floor().
122 */
123 if (format == ZFS_NICENUM_TIME) {
124 if (snprintf(buf, buflen, "%d%s",
125 (unsigned int) floor(val), u) <= 5)
126 break;
127
128 } else {
129 if (snprintf(buf, buflen, "%.*f%s", i,
130 val, u) <= 5)
131 break;
132 }
133 }
134 }
135 }
136
137 /*
138 * Convert a number to an appropriately human-readable output.
139 */
140 void
zfs_nicenum(uint64_t num,char * buf,size_t buflen)141 zfs_nicenum(uint64_t num, char *buf, size_t buflen)
142 {
143 zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_1024);
144 }
145
146 /*
147 * Convert a time to an appropriately human-readable output.
148 * @num: Time in nanoseconds
149 */
150 void
zfs_nicetime(uint64_t num,char * buf,size_t buflen)151 zfs_nicetime(uint64_t num, char *buf, size_t buflen)
152 {
153 zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_TIME);
154 }
155
156 /*
157 * Print out a raw number with correct column spacing
158 */
159 void
zfs_niceraw(uint64_t num,char * buf,size_t buflen)160 zfs_niceraw(uint64_t num, char *buf, size_t buflen)
161 {
162 zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_RAW);
163 }
164
165 /*
166 * Convert a number of bytes to an appropriately human-readable output.
167 */
168 void
zfs_nicebytes(uint64_t num,char * buf,size_t buflen)169 zfs_nicebytes(uint64_t num, char *buf, size_t buflen)
170 {
171 zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_BYTES);
172 }
173