projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 3c9f3681 JB |
1 | /* |
| 2 | * Helpers for formatting and printing strings | |
| 3 | * | |
| 4 | * Copyright 31 August 2008 James Bottomley | |
| 5 | */ | |
| 6 | #include <linux/kernel.h> | |
| 7 | #include <linux/math64.h> | |
| 8 | #include <linux/module.h> | |
| 9 | #include <linux/string_helpers.h> | |
| 10 | ||
| 11 | /** | |
| 12 | * string_get_size - get the size in the specified units | |
| 13 | * @size: The size to be converted | |
| 14 | * @units: units to use (powers of 1000 or 1024) | |
| 15 | * @buf: buffer to format to | |
| 16 | * @len: length of buffer | |
| 17 | * | |
| 18 | * This function returns a string formatted to 3 significant figures | |
| 19 | * giving the size in the required units. Returns 0 on success or | |
| 20 | * error on failure. @buf is always zero terminated. | |
| 21 | * | |
| 22 | */ | |
| 23 | int string_get_size(u64 size, const enum string_size_units units, | |
| 24 | char *buf, int len) | |
| 25 | { | |
| 26 | const char *units_10[] = { "B", "KB", "MB", "GB", "TB", "PB", | |
| 27 | "EB", "ZB", "YB", NULL}; | |
| 28 | const char *units_2[] = {"B", "KiB", "MiB", "GiB", "TiB", "PiB", | |
| 29 | "EiB", "ZiB", "YiB", NULL }; | |
| 30 | const char **units_str[] = { | |
| 31 | [STRING_UNITS_10] = units_10, | |
| 32 | [STRING_UNITS_2] = units_2, | |
| 33 | }; | |
| 34 | const int divisor[] = { | |
| 35 | [STRING_UNITS_10] = 1000, | |
| 36 | [STRING_UNITS_2] = 1024, | |
| 37 | }; | |
| 38 | int i, j; | |
| 39 | u64 remainder = 0, sf_cap; | |
| 40 | char tmp[8]; | |
| 41 | ||
| 42 | tmp[0] = '\0'; | |
| 43 | ||
| 44 | for (i = 0; size > divisor[units] && units_str[units][i]; i++) | |
| 45 | remainder = do_div(size, divisor[units]); | |
| 46 | ||
| 47 | sf_cap = size; | |
| 48 | for (j = 0; sf_cap*10 < 1000; j++) | |
| 49 | sf_cap *= 10; | |
| 50 | ||
| 51 | if (j) { | |
| 52 | remainder *= 1000; | |
| 53 | do_div(remainder, divisor[units]); | |
| 54 | snprintf(tmp, sizeof(tmp), ".%03lld", | |
| 55 | (unsigned long long)remainder); | |
| 56 | tmp[j+1] = '\0'; | |
| 57 | } | |
| 58 | ||
| 59 | snprintf(buf, len, "%lld%s%s", (unsigned long long)size, | |
| 60 | tmp, units_str[units][i]); | |
| 61 | ||
| 62 | return 0; | |
| 63 | } | |
| 64 | EXPORT_SYMBOL(string_get_size); |