1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3 * This file and its contents are supplied under the terms of the
4 * Common Development and Distribution License ("CDDL"), version 1.0.
5 * You may only use this file in accordance with the terms of version
6 * 1.0 of the CDDL.
7 *
8 * A full copy of the text of the CDDL should have accompanied this
9 * source. A copy of the CDDL is also available via the Internet at
10 * https://opensource.org/license/CDDL-1.0.
11 */
12
13 /*
14 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
15 */
16
17 #include <ctype.h>
18 #include <math.h>
19 #include <stdio.h>
20 #include <libzutil.h>
21 #include <string.h>
22
23 /*
24 * Return B_TRUE if "str" is a number string, B_FALSE otherwise.
25 * Works for integer and floating point numbers.
26 */
27 boolean_t
zfs_isnumber(const char * str)28 zfs_isnumber(const char *str)
29 {
30 if (!*str)
31 return (B_FALSE);
32
33 for (; *str; str++)
34 if (!(isdigit(*str) || (*str == '.')))
35 return (B_FALSE);
36
37 /*
38 * Numbers should not end with a period ("." ".." or "5." are
39 * not valid)
40 */
41 if (str[strlen(str) - 1] == '.') {
42 return (B_FALSE);
43 }
44
45 return (B_TRUE);
46 }
47
48 /*
49 * Convert a number to an appropriately human-readable output.
50 */
51 void
zfs_nicenum_format(uint64_t num,char * buf,size_t buflen,enum zfs_nicenum_format format)52 zfs_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 */
143 void
zfs_nicenum(uint64_t num,char * buf,size_t buflen)144 zfs_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 */
153 void
zfs_nicetime(uint64_t num,char * buf,size_t buflen)154 zfs_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 */
162 void
zfs_niceraw(uint64_t num,char * buf,size_t buflen)163 zfs_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 */
171 void
zfs_nicebytes(uint64_t num,char * buf,size_t buflen)172 zfs_nicebytes(uint64_t num, char *buf, size_t buflen)
173 {
174 zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_BYTES);
175 }
176