luxos/Kernel/library/stdlib/convert_ops.c

/*
 * convert_ops.c
 *
 *  Created on: Aug 27, 2011
 *      Author: Tiberiu
 */
#include <stdlib.h>

const string _Numbers = "0123456789abcdefghijklmnopqrstuvwxyz";

int32 ConvertIntToString (string buffer, int32 number, int32 base)
{
	if (base > 36 || base < 2) return 0;

	int32 len = numlen (number, base), beg = 0, i;
	uint32 n = (uint32) number;

	// If number is negative and in base 10, we put a '-' in front
	if (number < 0 && base == 10) buffer[beg++] = '-';

	// Put every digit in string
	for (i = len-1; i>=beg; i--)
	{
		buffer[i] = _Numbers[n % base];
		n /= base;
	}

	buffer[len] = 0;
	return number;
}

uint32 ConvertUIntToString (string buffer, uint32 number, int32 base)
{
	if (base > 36 || base < 2) return 0;

	int32 len = unumlen (number, base), i;

	// Put every digit in string
	for (i = len-1; i >= 0; i--)
	{
		buffer[i] = _Numbers[number % base];
		number /= base;
	}

	buffer[len] = 0;
	return number;
}

int32 ConvertStringToInt (string buffer)
{
	int8 negative = (buffer[0] == '-');
	int32 pos = (buffer[0] == '-' );

	int32 number = 0;

	while (IsDigit(buffer[pos]))
	{
		number = number*10 + (buffer[pos] - '0');
		pos++;
	}

	if (negative) return -number;
	return number;
}

uint32 ConvertStringToUInt (string buffer)
{
	int32 pos = 0;
	int32 number = 0;

	while (IsDigit(buffer[pos]))
	{
		number = number*10 + (buffer[pos] - '0');
		pos++;
	}

	return number;
}

uint32 ConvertStringToIntHex (string buffer)
{
	int32 pos = 0;
	uint32 number = 0;

	// Skip first 2 digits if it is in format 0xXXXX...
	if (buffer[1] == 'x' || buffer[1] == 'X') pos = 2;

	while (IsHexDigit(buffer[pos]))
	{
		number = number*0x10;

		if (IsDigit(buffer[pos])) number += buffer[pos] - '0';
		else if (buffer[pos] >= 'a' && buffer[pos] <= 'f') number += 10 + buffer[pos] - 'a';
		else if (buffer[pos] >= 'A' && buffer[pos] <= 'F') number += 10 + buffer[pos] - 'A';

		pos++;
	}

	return number;
}