blob: a1041926c5e5aff50dc540227a89d9d76d17dfc6 [file] [log] [blame]
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
/*
* Cheesy number->string conversion, complete with carry rounding error.
*/
char *num2str(unsigned long num, int maxlen, int base, int pow2, int unit_base)
{
const char *postfix[] = { "", "K", "M", "G", "P", "E" };
const char *byte_postfix[] = { "", "B", "bit" };
const unsigned int thousand[] = { 1000, 1024 };
unsigned int modulo, decimals;
int byte_post_index = 0, post_index, carry = 0;
char tmp[32];
char *buf;
buf = malloc(128);
for (post_index = 0; base > 1; post_index++)
base /= thousand[!!pow2];
switch (unit_base) {
case 1:
byte_post_index = 2;
num *= 8;
break;
case 8:
byte_post_index = 1;
break;
}
modulo = -1U;
while (post_index < sizeof(postfix)) {
sprintf(tmp, "%lu", num);
if (strlen(tmp) <= maxlen)
break;
modulo = num % thousand[!!pow2];
num /= thousand[!!pow2];
carry = modulo >= thousand[!!pow2] / 2;
post_index++;
}
if (modulo == -1U) {
done:
sprintf(buf, "%lu%s%s", num, postfix[post_index],
byte_postfix[byte_post_index]);
return buf;
}
sprintf(tmp, "%lu", num);
decimals = maxlen - strlen(tmp);
if (decimals <= 1) {
if (carry)
num++;
goto done;
}
do {
sprintf(tmp, "%u", modulo);
if (strlen(tmp) <= decimals - 1)
break;
modulo = (modulo + 9) / 10;
} while (1);
sprintf(buf, "%lu.%u%s%s", num, modulo, postfix[post_index],
byte_postfix[byte_post_index]);
return buf;
}