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// MIT License, Copyright (c) 2020 Marvin Borner
#include <conv.h>
#include <def.h>
#include <math.h>
#include <mem.h>
#include <str.h>
int itoa(int value, char *buffer, int base)
{
char tmp[16];
char *tp = tmp;
int i;
unsigned v;
int sign = (base == 10 && value < 0);
if (sign)
v = -value;
else
v = (unsigned)value;
while (v || tp == tmp) {
i = v % base;
v /= base;
if (i < 10)
*tp++ = i + '0';
else
*tp++ = i + 'a' - 10;
}
int len = tp - tmp;
if (sign) {
*buffer++ = '-';
len++;
}
while (tp > tmp)
*buffer++ = *--tp;
return len;
}
static int normalize(f64 *val)
{
int exp = 0;
double value = *val;
while (value >= 1.0) {
value /= 10.0;
++exp;
}
while (value < 0.1) {
value *= 10.0;
--exp;
}
*val = value;
return exp;
}
#define FLOAT_WIDTH 5
char *ftoa(f64 value, char *buffer)
{
int exp = 0;
u32 loc = 0;
if (value == 0.0) {
buffer[0] = '0';
buffer[1] = '\0';
return buffer;
}
if (value < 0.0) {
*buffer++ = '-';
value = -value;
}
exp = normalize(&value);
while (exp > 0) {
int digit = value * 10;
*buffer++ = digit + '0';
value = value * 10 - digit;
++loc;
--exp;
}
if (loc == 0)
*buffer++ = '0';
*buffer++ = '.';
while (exp < 0 && loc < FLOAT_WIDTH) {
*buffer++ = '0';
--exp;
++loc;
}
while (loc < FLOAT_WIDTH) {
int digit = value * 10.0;
*buffer++ = digit + '0';
value = value * 10.0 - digit;
++loc;
}
*buffer = '\0';
return buffer;
}
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