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-rw-r--r--lib/string_helpers.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/lib/string_helpers.c b/lib/string_helpers.c
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index 00000000000..8347925030f
--- /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);