Commit | Line | Data |
---|---|---|
3d2d14bc | 1 | #include <assert.h> |
1ec3d69b JA |
2 | #include <stdlib.h> |
3 | #include <stdio.h> | |
4 | #include <string.h> | |
5 | ||
5e746820 | 6 | #include "../compiler/compiler.h" |
38b00241 | 7 | #include "../oslib/asprintf.h" |
5e746820 TK |
8 | #include "num2str.h" |
9 | ||
d694a6a7 RE |
10 | /** |
11 | * num2str() - Cheesy number->string conversion, complete with carry rounding error. | |
12 | * @num: quantity (e.g., number of blocks, bytes or bits) | |
9e55f2c7 | 13 | * @maxlen: max number of digits in the output string (not counting prefix and units, but counting .) |
d694a6a7 RE |
14 | * @base: multiplier for num (e.g., if num represents Ki, use 1024) |
15 | * @pow2: select unit prefix - 0=power-of-10 decimal SI, nonzero=power-of-2 binary IEC | |
41a87019 | 16 | * @units: select units - N2S_* constants defined in num2str.h |
d694a6a7 | 17 | * @returns a malloc'd buffer containing "number[<unit prefix>][<units>]" |
1ec3d69b | 18 | */ |
41a87019 | 19 | char *num2str(uint64_t num, int maxlen, int base, int pow2, enum n2s_unit units) |
1ec3d69b | 20 | { |
78c14fab BVA |
21 | const char *sistr[] = { "", "k", "M", "G", "T", "P", "E" }; |
22 | const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" }; | |
d694a6a7 | 23 | const char **unitprefix; |
cbb8289d BVA |
24 | static const char *const unitstr[] = { |
25 | [N2S_NONE] = "", | |
26 | [N2S_PERSEC] = "/s", | |
27 | [N2S_BYTE] = "B", | |
28 | [N2S_BIT] = "bit", | |
29 | [N2S_BYTEPERSEC]= "B/s", | |
30 | [N2S_BITPERSEC] = "bit/s" | |
31 | }; | |
3b6879b2 | 32 | const unsigned int thousand = pow2 ? 1024 : 1000; |
9e55f2c7 | 33 | unsigned int modulo; |
cbb8289d | 34 | int post_index, carry = 0; |
832a3186 | 35 | char tmp[32]; |
1ec3d69b JA |
36 | char *buf; |
37 | ||
d694a6a7 | 38 | compiletime_assert(sizeof(sistr) == sizeof(iecstr), "unit prefix arrays must be identical sizes"); |
59f94d26 | 39 | assert(units < FIO_ARRAY_SIZE(unitstr)); |
d694a6a7 | 40 | |
d694a6a7 RE |
41 | if (pow2) |
42 | unitprefix = iecstr; | |
43 | else | |
44 | unitprefix = sistr; | |
1ec3d69b JA |
45 | |
46 | for (post_index = 0; base > 1; post_index++) | |
3b6879b2 | 47 | base /= thousand; |
1ec3d69b | 48 | |
d694a6a7 | 49 | switch (units) { |
41a87019 BVA |
50 | case N2S_NONE: |
51 | break; | |
d694a6a7 | 52 | case N2S_PERSEC: |
d694a6a7 RE |
53 | break; |
54 | case N2S_BYTE: | |
d694a6a7 RE |
55 | break; |
56 | case N2S_BIT: | |
73798eb2 SN |
57 | num *= 8; |
58 | break; | |
d694a6a7 | 59 | case N2S_BYTEPERSEC: |
d694a6a7 RE |
60 | break; |
61 | case N2S_BITPERSEC: | |
d694a6a7 | 62 | num *= 8; |
73798eb2 SN |
63 | break; |
64 | } | |
65 | ||
9e55f2c7 TK |
66 | /* |
67 | * Divide by K/Ki until string length of num <= maxlen. | |
68 | */ | |
1ec3d69b | 69 | modulo = -1U; |
59f94d26 | 70 | while (post_index < FIO_ARRAY_SIZE(sistr)) { |
ca09be4b | 71 | sprintf(tmp, "%llu", (unsigned long long) num); |
1ec3d69b JA |
72 | if (strlen(tmp) <= maxlen) |
73 | break; | |
74 | ||
3b6879b2 BVA |
75 | modulo = num % thousand; |
76 | num /= thousand; | |
77 | carry = modulo >= thousand / 2; | |
1ec3d69b JA |
78 | post_index++; |
79 | } | |
80 | ||
59f94d26 | 81 | if (post_index >= FIO_ARRAY_SIZE(sistr)) |
fd99605c BVA |
82 | post_index = 0; |
83 | ||
9e55f2c7 TK |
84 | /* |
85 | * If no modulo, then we're done. | |
86 | */ | |
1ec3d69b JA |
87 | if (modulo == -1U) { |
88 | done: | |
38b00241 BVA |
89 | if (asprintf(&buf, "%llu%s%s", (unsigned long long) num, |
90 | unitprefix[post_index], unitstr[units]) < 0) | |
91 | buf = NULL; | |
1ec3d69b JA |
92 | return buf; |
93 | } | |
94 | ||
9e55f2c7 TK |
95 | /* |
96 | * If no room for decimals, then we're done. | |
97 | */ | |
ca09be4b | 98 | sprintf(tmp, "%llu", (unsigned long long) num); |
9e55f2c7 | 99 | if ((int)(maxlen - strlen(tmp)) <= 1) { |
05463816 JA |
100 | if (carry) |
101 | num++; | |
1ec3d69b | 102 | goto done; |
05463816 JA |
103 | } |
104 | ||
9e55f2c7 TK |
105 | /* |
106 | * Fill in everything and return the result. | |
107 | */ | |
108 | assert(maxlen - strlen(tmp) - 1 > 0); | |
3b6879b2 | 109 | assert(modulo < thousand); |
832a3186 BVA |
110 | sprintf(tmp, "%.*f", (int)(maxlen - strlen(tmp) - 1), |
111 | (double)modulo / (double)thousand); | |
1ec3d69b | 112 | |
c736b361 | 113 | if (tmp[0] == '1') |
114 | num++; | |
115 | ||
38b00241 BVA |
116 | if (asprintf(&buf, "%llu.%s%s%s", (unsigned long long) num, &tmp[2], |
117 | unitprefix[post_index], unitstr[units]) < 0) | |
118 | buf = NULL; | |
1ec3d69b JA |
119 | return buf; |
120 | } |