diff options
| -rw-r--r-- | include/linux/string_helpers.h | 16 | ||||
| -rw-r--r-- | lib/Makefile | 3 | ||||
| -rw-r--r-- | lib/string_helpers.c | 64 |
3 files changed, 82 insertions, 1 deletions
diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h new file mode 100644 index 0000000..a3eb2f6 --- /dev/null +++ b/include/linux/string_helpers.h @@ -0,0 +1,16 @@ +#ifndef _LINUX_STRING_HELPERS_H_ +#define _LINUX_STRING_HELPERS_H_ + +#include <linux/types.h> + +/* Descriptions of the types of units to + * print in */ +enum string_size_units { + STRING_UNITS_10, /* use powers of 10^3 (standard SI) */ + STRING_UNITS_2, /* use binary powers of 2^10 */ +}; + +int string_get_size(u64 size, enum string_size_units units, + char *buf, int len); + +#endif diff --git a/lib/Makefile b/lib/Makefile index 3b1f94b..44001af 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -19,7 +19,8 @@ lib-$(CONFIG_SMP) += cpumask.o lib-y += kobject.o kref.o klist.o obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ - bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o + bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ + string_helpers.o ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff --git a/lib/string_helpers.c b/lib/string_helpers.c new file mode 100644 index 0000000..8347925 --- /dev/null +++ b/lib/string_helpers.c @@ -0,0 +1,64 @@ +/* + * Helpers for formatting and printing strings + * + * Copyright 31 August 2008 James Bottomley + */ +#include <linux/kernel.h> +#include <linux/math64.h> +#include <linux/module.h> +#include <linux/string_helpers.h> + +/** + * string_get_size - get the size in the specified units + * @size: The size to be converted + * @units: units to use (powers of 1000 or 1024) + * @buf: buffer to format to + * @len: length of buffer + * + * This function returns a string formatted to 3 significant figures + * giving the size in the required units. Returns 0 on success or + * error on failure. @buf is always zero terminated. + * + */ +int string_get_size(u64 size, const enum string_size_units units, + char *buf, int len) +{ + const char *units_10[] = { "B", "KB", "MB", "GB", "TB", "PB", + "EB", "ZB", "YB", NULL}; + const char *units_2[] = {"B", "KiB", "MiB", "GiB", "TiB", "PiB", + "EiB", "ZiB", "YiB", NULL }; + const char **units_str[] = { + [STRING_UNITS_10] = units_10, + [STRING_UNITS_2] = units_2, + }; + const int divisor[] = { + [STRING_UNITS_10] = 1000, + [STRING_UNITS_2] = 1024, + }; + int i, j; + u64 remainder = 0, sf_cap; + char tmp[8]; + + tmp[0] = '\0'; + + for (i = 0; size > divisor[units] && units_str[units][i]; i++) + remainder = do_div(size, divisor[units]); + + sf_cap = size; + for (j = 0; sf_cap*10 < 1000; j++) + sf_cap *= 10; + + if (j) { + remainder *= 1000; + do_div(remainder, divisor[units]); + snprintf(tmp, sizeof(tmp), ".%03lld", + (unsigned long long)remainder); + tmp[j+1] = '\0'; + } + + snprintf(buf, len, "%lld%s%s", (unsigned long long)size, + tmp, units_str[units][i]); + + return 0; +} +EXPORT_SYMBOL(string_get_size); |