long2num.c

Go to the documentation of this file.

/*
   +----------------------------------------------------------------------+
   | Copyright (c) The PHP Group                                          |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | https://www.php.net/license/3_01.txt                                 |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Saki Takamachi <saki@php.net>                               |
   +----------------------------------------------------------------------+
*/
 
#include "bcmath.h"
#include <stdbool.h>
#include "convert.h"
 
#define BC_LONG_MAX_DIGITS (sizeof(LONG_MIN_DIGITS) - 1)
 
bc_num bc_long2num(zend_long lval)
{
    bc_num num;
 
    if (UNEXPECTED(lval == 0)) {
        num = bc_copy_num(BCG(_zero_));
        return num;
    }
 
    bool negative = lval < 0;
    if (UNEXPECTED(lval == ZEND_LONG_MIN)) {
        num = bc_new_num_nonzeroed(BC_LONG_MAX_DIGITS, 0);
        const char *ptr = LONG_MIN_DIGITS;
        bc_copy_and_toggle_bcd(num->n_value, ptr, ptr + BC_LONG_MAX_DIGITS);
        num->n_sign = MINUS;
        return num;
    } else if (negative) {
        lval = -lval;
    }
 
    zend_long tmp = lval;
    size_t len = 0;
    while (tmp > 0) {
        tmp /= BASE;
        len++;
    }
 
    num = bc_new_num_nonzeroed(len, 0);
    char *ptr = num->n_value + len - 1;
    for (; len > 0; len--) {
        *ptr-- = lval % BASE;
        lval /= BASE;
    }
    num->n_sign = negative ? MINUS : PLUS;
 
    return num;
}