blob: b4e0ef181a0decb9ea43f2f76a4a99f151c3cacc
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * June 30, 2001 Manuel Novoa III |
4 | * |
5 | * All-integer version (hey, not everyone has floating point) of |
6 | * make_human_readable_str, modified from similar code I had written |
7 | * for busybox several months ago. |
8 | * |
9 | * Notes: |
10 | * 1) I'm using an unsigned long long to hold the product size * block_size, |
11 | * as df (which calls this routine) could request a representation of a |
12 | * partition size in bytes > max of unsigned long. If long longs aren't |
13 | * available, it would be possible to do what's needed using polynomial |
14 | * representations (say, powers of 1024) and manipulating coefficients. |
15 | * The base ten "bytes" output could be handled similarly. |
16 | * |
17 | * 2) This routine outputs a decimal point and a tenths digit when |
18 | * display_unit == 0. Hence, it isn't uncommon for the returned string |
19 | * to have a length of 5 or 6. |
20 | * |
21 | * If block_size is also 0, no decimal digits are printed. |
22 | * |
23 | * Licensed under GPLv2, see file LICENSE in this source tree. |
24 | */ |
25 | |
26 | #include "libbb.h" |
27 | |
28 | const char* FAST_FUNC make_human_readable_str(unsigned long long val, |
29 | unsigned long block_size, unsigned long display_unit) |
30 | { |
31 | static const char unit_chars[] ALIGN1 = { |
32 | '\0', 'K', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y' |
33 | }; |
34 | |
35 | unsigned frac; /* 0..9 - the fractional digit */ |
36 | const char *u; |
37 | const char *fmt; |
38 | |
39 | if (val == 0) |
40 | return "0"; |
41 | |
42 | fmt = "%llu"; |
43 | if (block_size > 1) |
44 | val *= block_size; |
45 | frac = 0; |
46 | u = unit_chars; |
47 | |
48 | if (display_unit) { |
49 | val += display_unit/2; /* Deal with rounding */ |
50 | val /= display_unit; /* Don't combine with the line above! */ |
51 | /* will just print it as ulonglong (below) */ |
52 | } else { |
53 | while ((val >= 1024) |
54 | /* && (u < unit_chars + sizeof(unit_chars) - 1) - always true */ |
55 | ) { |
56 | fmt = "%llu.%u%c"; |
57 | u++; |
58 | frac = (((unsigned)val % 1024) * 10 + 1024/2) / 1024; |
59 | val /= 1024; |
60 | } |
61 | if (frac >= 10) { /* we need to round up here */ |
62 | ++val; |
63 | frac = 0; |
64 | } |
65 | #if 1 |
66 | /* If block_size is 0, dont print fractional part */ |
67 | if (block_size == 0) { |
68 | if (frac >= 5) { |
69 | ++val; |
70 | } |
71 | fmt = "%llu%*c"; |
72 | frac = 1; |
73 | } |
74 | #endif |
75 | } |
76 | |
77 | return auto_string(xasprintf(fmt, val, frac, *u)); |
78 | } |
79 | |
80 | |
81 | /* vda's implementations of the similar idea */ |
82 | |
83 | /* Convert unsigned long long value into compact 5-char representation. |
84 | * String is not terminated (buf[5] is untouched) */ |
85 | char* FAST_FUNC smart_ulltoa5(unsigned long long ul, char buf[5], const char *scale) |
86 | { |
87 | const char *fmt; |
88 | char c; |
89 | unsigned v, u, idx = 0; |
90 | |
91 | if (ul > 99999) { // do not scale if 99999 or less |
92 | ul *= 10; |
93 | do { |
94 | ul /= 1024; |
95 | idx++; |
96 | } while (ul >= 100000); |
97 | } |
98 | v = ul; // ullong divisions are expensive, avoid them |
99 | |
100 | fmt = " 123456789"; |
101 | u = v / 10; |
102 | v = v % 10; |
103 | if (!idx) { |
104 | // 99999 or less: use "12345" format |
105 | // u is value/10, v is last digit |
106 | c = buf[0] = " 123456789"[u/1000]; |
107 | if (c != ' ') fmt = "0123456789"; |
108 | c = buf[1] = fmt[u/100%10]; |
109 | if (c != ' ') fmt = "0123456789"; |
110 | c = buf[2] = fmt[u/10%10]; |
111 | if (c != ' ') fmt = "0123456789"; |
112 | buf[3] = fmt[u%10]; |
113 | buf[4] = "0123456789"[v]; |
114 | } else { |
115 | // value has been scaled into 0..9999.9 range |
116 | // u is value, v is 1/10ths (allows for 92.1M format) |
117 | if (u >= 100) { |
118 | // value is >= 100: use "1234M', " 123M" formats |
119 | c = buf[0] = " 123456789"[u/1000]; |
120 | if (c != ' ') fmt = "0123456789"; |
121 | c = buf[1] = fmt[u/100%10]; |
122 | if (c != ' ') fmt = "0123456789"; |
123 | v = u % 10; |
124 | u = u / 10; |
125 | buf[2] = fmt[u%10]; |
126 | } else { |
127 | // value is < 100: use "92.1M" format |
128 | c = buf[0] = " 123456789"[u/10]; |
129 | if (c != ' ') fmt = "0123456789"; |
130 | buf[1] = fmt[u%10]; |
131 | buf[2] = '.'; |
132 | } |
133 | buf[3] = "0123456789"[v]; |
134 | buf[4] = scale[idx]; /* typically scale = " kmgt..." */ |
135 | } |
136 | return buf + 5; |
137 | } |
138 | |
139 | /* Convert unsigned long long value into compact 4-char |
140 | * representation. Examples: "1234", "1.2k", " 27M", "123T" |
141 | * String is not terminated (buf[4] is untouched) */ |
142 | char* FAST_FUNC smart_ulltoa4(unsigned long long ul, char buf[4], const char *scale) |
143 | { |
144 | const char *fmt; |
145 | char c; |
146 | unsigned v, u, idx = 0; |
147 | |
148 | if (ul > 9999) { // do not scale if 9999 or less |
149 | ul *= 10; |
150 | do { |
151 | ul /= 1024; |
152 | idx++; |
153 | } while (ul >= 10000); |
154 | } |
155 | v = ul; // ullong divisions are expensive, avoid them |
156 | |
157 | fmt = " 123456789"; |
158 | u = v / 10; |
159 | v = v % 10; |
160 | if (!idx) { |
161 | // 9999 or less: use "1234" format |
162 | // u is value/10, v is last digit |
163 | c = buf[0] = " 123456789"[u/100]; |
164 | if (c != ' ') fmt = "0123456789"; |
165 | c = buf[1] = fmt[u/10%10]; |
166 | if (c != ' ') fmt = "0123456789"; |
167 | buf[2] = fmt[u%10]; |
168 | buf[3] = "0123456789"[v]; |
169 | } else { |
170 | // u is value, v is 1/10ths (allows for 9.2M format) |
171 | if (u >= 10) { |
172 | // value is >= 10: use "123M', " 12M" formats |
173 | c = buf[0] = " 123456789"[u/100]; |
174 | if (c != ' ') fmt = "0123456789"; |
175 | v = u % 10; |
176 | u = u / 10; |
177 | buf[1] = fmt[u%10]; |
178 | } else { |
179 | // value is < 10: use "9.2M" format |
180 | buf[0] = "0123456789"[u]; |
181 | buf[1] = '.'; |
182 | } |
183 | buf[2] = "0123456789"[v]; |
184 | buf[3] = scale[idx]; /* typically scale = " kmgt..." */ |
185 | } |
186 | return buf + 4; |
187 | } |
188 |