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ITOA.c
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ITOA.c
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/*
* ITOA.c
*
* Created on: May 12, 2021
* Author: karl.yamashita
*
*
* This was made for Microblaze because Standar C library used too much memory.
* Later found out Xilinx has their own Standard C library.
*
*
* Credit to: https://www.techiedelight.com/implement-itoa-function-in-c/
*
*/
#include "main.h"
#include "ITOA.h"
static void swap(char *x, char *y);
static char* reverse(char *buffer, int i, int j);
// Function to swap two numbers
static void swap(char *x, char *y) {
char t = *x; *x = *y; *y = t;
}
// Function to reverse `buffer[i�j]`
static char* reverse(char *buffer, int i, int j)
{
while (i < j) {
swap(&buffer[i++], &buffer[j--]);
}
return buffer;
}
/*
* Description: converts an integer to char array.
*
* Input: the value to convert, the array buffer to hold result, the base number to convert to (base: 2, 8, 10 or 16)
* Output:
*/
char* itoa(int value, char* buffer, int base)
{
// invalid input
if (base < 2 || base > 32) {
return buffer;
}
// consider the absolute value of the number
int n = abs(value);
int i = 0;
while (n)
{
int r = n % base;
if (r >= 10) {
buffer[i++] = 65 + (r - 10);
}
else {
buffer[i++] = 48 + r;
}
n = n / base;
}
// if the number is 0
if (i == 0) {
buffer[i++] = '0';
}
// If the base is 10 and the value is negative, the resulting string
// is preceded with a minus sign (-)
// With any other base, value is always considered unsigned
if (value < 0 && base == 10) {
buffer[i++] = '-';
}
buffer[i] = '\0'; // null terminate string
// reverse the string and return it
return reverse(buffer, 0, i - 1);
}