archived-php-src/ext/bcmath/libbcmath/src/output.c

/* output.c: bcmath library file. */
/*
    Copyright (C) 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc.
    Copyright (C) 2000 Philip A. Nelson

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.  (LICENSE)

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to:

      The Free Software Foundation, Inc.
      59 Temple Place, Suite 330
      Boston, MA 02111-1307 USA.

    You may contact the author by:
       e-mail:  philnelson@acm.org
      us-mail:  Philip A. Nelson
                Computer Science Department, 9062
                Western Washington University
                Bellingham, WA 98226-9062

*************************************************************************/

#include "bcmath.h"
#include <stdbool.h>
#include <string.h>
#include "zend_alloc.h"


/* The following routines provide output for bcd numbers package
   using the rules of POSIX bc for output. */

/* This structure is used for saving digits in the conversion process. */
typedef struct stk_rec {
	long digit;
	struct stk_rec *next;
} stk_rec;

/* The reference string for digits. */
static const char ref_str[] = "0123456789ABCDEF";


/* A special output routine for "multi-character digits."  Exactly
   SIZE characters must be output for the value VAL.  If SPACE is
   non-zero, we must output one space before the number.  OUT_CHAR
   is the actual routine for writing the characters. */

void bc_out_long(long val, size_t size, bool space, void (*out_char)(char))
{
	char digits[40];
	size_t len, ix;

	if (space) (*out_char)(' ');
	snprintf(digits, sizeof(digits), "%ld", val);
	len = strlen(digits);
	while (size > len) {
		(*out_char)('0');
		size--;
	}
	for (ix = 0; ix < len; ix++) {
		(*out_char)(digits[ix]);
	}
}

/* Output of a bcd number.  NUM is written in base O_BASE using OUT_CHAR
   as the routine to do the actual output of the characters. */

void bc_out_num(bc_num num, int o_base, void (*out_char)(char), bool leading_zero)
{
	char *nptr;
	int index, fdigit;
	bool pre_space;
	stk_rec *digits, *temp;
	bc_num int_part, frac_part, base, cur_dig, t_num, max_o_digit;

	/* The negative sign if needed. */
	if (num->n_sign == MINUS) (*out_char)('-');

	/* Output the number. */
	if (bc_is_zero(num)) {
		(*out_char)('0');
	} else {
		if (o_base == 10) {
			/* The number is in base 10, do it the fast way. */
			nptr = num->n_value;
			if (num->n_len > 1 || *nptr != 0) {
				for (index = num->n_len; index > 0; index--) {
					(*out_char)(BCD_CHAR(*nptr++));
				}
			} else {
				nptr++;
			}

			if (leading_zero && bc_is_zero(num)) {
				(*out_char)('0');
			}

			/* Now the fraction. */
			if (num->n_scale > 0) {
				(*out_char)('.');
				for (index = 0; index < num->n_scale; index++) {
					(*out_char)(BCD_CHAR(*nptr++));
				}
			}
		} else {
			/* special case ... */
			if (leading_zero && bc_is_zero(num)) {
				(*out_char)('0');
			}

			/* The number is some other base. */
			digits = NULL;
			bc_init_num(&int_part);
			bc_divide(num, BCG(_one_), &int_part, 0);
			bc_init_num(&frac_part);
			bc_init_num(&cur_dig);
			bc_init_num(&base);
			bc_sub(num, int_part, &frac_part, 0);
			/* Make the INT_PART and FRAC_PART positive. */
			int_part->n_sign = PLUS;
			frac_part->n_sign = PLUS;
			bc_int2num(&base, o_base);
			bc_init_num(&max_o_digit);
			bc_int2num(&max_o_digit, o_base - 1);

			/* Get the digits of the integer part and push them on a stack. */
			while (!bc_is_zero(int_part)) {
				bc_modulo(int_part, base, &cur_dig, 0);
				/* PHP Change: malloc() -> emalloc() */
				temp = (stk_rec *) emalloc(sizeof(stk_rec));
				temp->digit = bc_num2long(cur_dig);
				temp->next = digits;
				digits = temp;
				bc_divide(int_part, base, &int_part, 0);
			}

			/* Print the digits on the stack. */
			if (digits != NULL) {
				/* Output the digits. */
				while (digits != NULL) {
					temp = digits;
					digits = digits->next;
					if (o_base <= 16) {
						(*out_char)(ref_str[(int) temp->digit]);
					} else {
						bc_out_long(temp->digit, max_o_digit->n_len, 1, out_char);
					}
					efree(temp);
				}
			}

			/* Get and print the digits of the fraction part. */
			if (num->n_scale > 0) {
				(*out_char)('.');
				pre_space = false;
				t_num = bc_copy_num(BCG(_one_));
				while (t_num->n_len <= num->n_scale) {
					bc_multiply(frac_part, base, &frac_part, num->n_scale);
					fdigit = bc_num2long(frac_part);
					bc_int2num(&int_part, fdigit);
					bc_sub(frac_part, int_part, &frac_part, 0);
					if (o_base <= 16) {
						(*out_char)(ref_str[fdigit]);
					} else {
						bc_out_long(fdigit, max_o_digit->n_len, pre_space, out_char);
						pre_space = true;
					}
					bc_multiply(t_num, base, &t_num, 0);
				}
				bc_free_num (&t_num);
			}

			/* Clean up. */
			bc_free_num (&int_part);
			bc_free_num (&frac_part);
			bc_free_num (&base);
			bc_free_num (&cur_dig);
			bc_free_num (&max_o_digit);
		}
	}
}