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/* Copyright (c) 2014 Corinna Vinschen <corinna@vinschen.de> */
/*
FUNCTION
<<itoa>>---integer to string
INDEX
itoa
SYNOPSIS
#include <stdlib.h>
char *itoa(int <[value]>, char *<[str]>, int <[base]>);
char *__itoa(int <[value]>, char *<[str]>, int <[base]>);
DESCRIPTION
<<itoa>> converts the integer <[value]> to a null-terminated string
using the specified base, which must be between 2 and 36, inclusive.
If <[base]> is 10, <[value]> is treated as signed and the string will be
prefixed with '-' if negative. For all other bases, <[value]> is treated as
unsigned. <[str]> should be an array long enough to contain the converted
value, which in the worst case is sizeof(int)*8+1 bytes.
RETURNS
A pointer to the string, <[str]>, or NULL if <[base]> is invalid.
PORTABILITY
<<itoa>> is non-ANSI.
No supporting OS subroutine calls are required.
*/
#define _DEFAULT_SOURCE
#include <stdlib.h>
char *
__itoa(int value, char *str, int base)
{
unsigned uvalue;
int i = 0;
/* Check base is supported. */
if ((base < 2) || (base > 36)) {
str[0] = '\0';
return NULL;
}
/* Negative numbers are only supported for decimal.
* Cast to unsigned to avoid overflow for maximum negative value. */
if ((base == 10) && (value < 0)) {
str[i++] = '-';
uvalue = (unsigned)-value;
} else
uvalue = (unsigned)value;
__utoa(uvalue, &str[i], base);
return str;
}
char *
itoa(int value, char *str, int base)
{
return __itoa(value, str, base);
}