| | 1 | #include <stdlib.h> |
| | 2 | #include <stdio.h> |
| | 3 | #include <string.h> |
| | 4 | |
| | 5 | #include "../compiler/compiler.h" |
| | 6 | #include "num2str.h" |
| | 7 | |
| | 8 | #define ARRAY_SIZE(x) (sizeof((x)) / (sizeof((x)[0]))) |
| | 9 | |
| | 10 | /** |
| | 11 | * num2str() - Cheesy number->string conversion, complete with carry rounding error. |
| | 12 | * @num: quantity (e.g., number of blocks, bytes or bits) |
| | 13 | * @maxlen: max number of digits in the output string (not counting prefix and units) |
| | 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 |
| | 16 | * @units: select units - N2S_* macros defined in num2str.h |
| | 17 | * @returns a malloc'd buffer containing "number[<unit prefix>][<units>]" |
| | 18 | */ |
| | 19 | char *num2str(uint64_t num, int maxlen, int base, int pow2, int units) |
| | 20 | { |
| | 21 | const char *sistr[] = { "", "k", "M", "G", "T", "P" }; |
| | 22 | const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi" }; |
| | 23 | const char **unitprefix; |
| | 24 | const char *unitstr[] = { "", "/s", "B", "bit", "B/s", "bit/s" }; |
| | 25 | const unsigned int thousand[] = { 1000, 1024 }; |
| | 26 | unsigned int modulo, decimals; |
| | 27 | int unit_index = 0, post_index, carry = 0; |
| | 28 | char tmp[32]; |
| | 29 | char *buf; |
| | 30 | |
| | 31 | compiletime_assert(sizeof(sistr) == sizeof(iecstr), "unit prefix arrays must be identical sizes"); |
| | 32 | |
| | 33 | buf = malloc(128); |
| | 34 | if (!buf) |
| | 35 | return NULL; |
| | 36 | |
| | 37 | if (pow2) |
| | 38 | unitprefix = iecstr; |
| | 39 | else |
| | 40 | unitprefix = sistr; |
| | 41 | |
| | 42 | for (post_index = 0; base > 1; post_index++) |
| | 43 | base /= thousand[!!pow2]; |
| | 44 | |
| | 45 | switch (units) { |
| | 46 | case N2S_PERSEC: |
| | 47 | unit_index = 1; |
| | 48 | break; |
| | 49 | case N2S_BYTE: |
| | 50 | unit_index = 2; |
| | 51 | break; |
| | 52 | case N2S_BIT: |
| | 53 | unit_index = 3; |
| | 54 | num *= 8; |
| | 55 | break; |
| | 56 | case N2S_BYTEPERSEC: |
| | 57 | unit_index = 4; |
| | 58 | break; |
| | 59 | case N2S_BITPERSEC: |
| | 60 | unit_index = 5; |
| | 61 | num *= 8; |
| | 62 | break; |
| | 63 | } |
| | 64 | |
| | 65 | modulo = -1U; |
| | 66 | while (post_index < sizeof(sistr)) { |
| | 67 | sprintf(tmp, "%llu", (unsigned long long) num); |
| | 68 | if (strlen(tmp) <= maxlen) |
| | 69 | break; |
| | 70 | |
| | 71 | modulo = num % thousand[!!pow2]; |
| | 72 | num /= thousand[!!pow2]; |
| | 73 | carry = modulo >= thousand[!!pow2] / 2; |
| | 74 | post_index++; |
| | 75 | } |
| | 76 | |
| | 77 | if (modulo == -1U) { |
| | 78 | done: |
| | 79 | if (post_index >= ARRAY_SIZE(sistr)) |
| | 80 | post_index = 0; |
| | 81 | |
| | 82 | sprintf(buf, "%llu%s%s", (unsigned long long) num, |
| | 83 | unitprefix[post_index], unitstr[unit_index]); |
| | 84 | return buf; |
| | 85 | } |
| | 86 | |
| | 87 | sprintf(tmp, "%llu", (unsigned long long) num); |
| | 88 | decimals = maxlen - strlen(tmp); |
| | 89 | if (decimals <= 1) { |
| | 90 | if (carry) |
| | 91 | num++; |
| | 92 | goto done; |
| | 93 | } |
| | 94 | |
| | 95 | do { |
| | 96 | sprintf(tmp, "%u", modulo); |
| | 97 | if (strlen(tmp) <= decimals - 1) |
| | 98 | break; |
| | 99 | |
| | 100 | modulo = (modulo + 9) / 10; |
| | 101 | } while (1); |
| | 102 | |
| | 103 | sprintf(buf, "%llu.%u%s%s", (unsigned long long) num, modulo, |
| | 104 | unitprefix[post_index], unitstr[unit_index]); |
| | 105 | return buf; |
| | 106 | } |
projects / fio.git / blame_incremental