* @maxlen: max number of digits in the output string (not counting prefix and units, but counting .)
* @base: multiplier for num (e.g., if num represents Ki, use 1024)
* @pow2: select unit prefix - 0=power-of-10 decimal SI, nonzero=power-of-2 binary IEC
- * @units: select units - N2S_* macros defined in num2str.h
+ * @units: select units - N2S_* constants defined in num2str.h
* @returns a malloc'd buffer containing "number[<unit prefix>][<units>]"
*/
-char *num2str(uint64_t num, int maxlen, int base, int pow2, int units)
+char *num2str(uint64_t num, int maxlen, int base, int pow2, enum n2s_unit units)
{
const char *sistr[] = { "", "k", "M", "G", "T", "P" };
const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi" };
const char **unitprefix;
- const char *unitstr[] = { "", "/s", "B", "bit", "B/s", "bit/s" };
- const unsigned int thousand[] = { 1000, 1024 };
+ static const char *const unitstr[] = {
+ [N2S_NONE] = "",
+ [N2S_PERSEC] = "/s",
+ [N2S_BYTE] = "B",
+ [N2S_BIT] = "bit",
+ [N2S_BYTEPERSEC]= "B/s",
+ [N2S_BITPERSEC] = "bit/s"
+ };
+ const unsigned int thousand = pow2 ? 1024 : 1000;
unsigned int modulo;
- int unit_index = 0, post_index, carry = 0;
+ int post_index, carry = 0;
char tmp[32], fmt[32];
char *buf;
compiletime_assert(sizeof(sistr) == sizeof(iecstr), "unit prefix arrays must be identical sizes");
+ assert(units < ARRAY_SIZE(unitstr));
buf = malloc(128);
if (!buf)
unitprefix = sistr;
for (post_index = 0; base > 1; post_index++)
- base /= thousand[!!pow2];
+ base /= thousand;
switch (units) {
+ case N2S_NONE:
+ break;
case N2S_PERSEC:
- unit_index = 1;
break;
case N2S_BYTE:
- unit_index = 2;
break;
case N2S_BIT:
- unit_index = 3;
num *= 8;
break;
case N2S_BYTEPERSEC:
- unit_index = 4;
break;
case N2S_BITPERSEC:
- unit_index = 5;
num *= 8;
break;
}
* Divide by K/Ki until string length of num <= maxlen.
*/
modulo = -1U;
- while (post_index < sizeof(sistr)) {
+ while (post_index < ARRAY_SIZE(sistr)) {
sprintf(tmp, "%llu", (unsigned long long) num);
if (strlen(tmp) <= maxlen)
break;
- modulo = num % thousand[!!pow2];
- num /= thousand[!!pow2];
- carry = modulo >= thousand[!!pow2] / 2;
+ modulo = num % thousand;
+ num /= thousand;
+ carry = modulo >= thousand / 2;
post_index++;
}
post_index = 0;
sprintf(buf, "%llu%s%s", (unsigned long long) num,
- unitprefix[post_index], unitstr[unit_index]);
+ unitprefix[post_index], unitstr[units]);
return buf;
}
* Fill in everything and return the result.
*/
assert(maxlen - strlen(tmp) - 1 > 0);
- assert(modulo < thousand[!!pow2]);
+ assert(modulo < thousand);
sprintf(fmt, "%%.%df", (int)(maxlen - strlen(tmp) - 1));
- sprintf(tmp, fmt, (double)modulo / (double)thousand[!!pow2]);
+ sprintf(tmp, fmt, (double)modulo / (double)thousand);
sprintf(buf, "%llu.%s%s%s", (unsigned long long) num, &tmp[2],
- unitprefix[post_index], unitstr[unit_index]);
+ unitprefix[post_index], unitstr[units]);
return buf;
}