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number.c
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number.c
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/*
+----------------------------------------------------------------------+
| Modified for PHP by Andi Gutmans <andi@zend.com> |
+----------------------------------------------------------------------+
*/
/* number.c: Implements arbitrary precision numbers. */
/* This file is part of GNU bc.
Copyright (C) 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License , or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
You may contact the author by:
e-mail: phil@cs.wwu.edu
us-mail: Philip A. Nelson
Computer Science Department, 9062
Western Washington University
Bellingham, WA 98226-9062
*************************************************************************/
#if 0
#include "bcdefs.h"
#include "proto.h"
#include "global.h"
#endif
#include "number.h"
#include "php.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* Storage used for special numbers. */
#ifndef THREAD_SAFE
bc_num _zero_;
bc_num _one_;
bc_num _two_;
#endif
#define rt_warn(msg) php3_error(E_WARNING,msg)
#define rt_error(msg) php3_error(E_WARNING,msg)
void out_of_memory()
{
}
/* "Frees" a bc_num NUM. Actually decreases reference count and only
efrees the storage if reference count is zero. */
void
free_num (num)
bc_num *num;
{
if (*num == NULL) return;
(*num)->n_refs--;
if ((*num)->n_refs == 0) efree(*num);
*num = NULL;
}
/* new_num allocates a number and sets fields to known values. */
bc_num
new_num (length, scale)
int length, scale;
{
bc_num temp;
temp = (bc_num) emalloc (sizeof(bc_struct)+length+scale);
if (temp == NULL) out_of_memory ();
temp->n_sign = PLUS;
temp->n_len = length;
temp->n_scale = scale;
temp->n_refs = 1;
temp->n_value[0] = 0;
return temp;
}
/* Intitialize the number package! */
void init_numbers (void)
{
_zero_ = new_num (1,0);
_one_ = new_num (1,0);
_one_->n_value[0] = 1;
_two_ = new_num (1,0);
_two_->n_value[0] = 2;
}
/* Intitialize the number package! */
void
destruct_numbers ()
{
free_num(&_zero_);
free_num(&_one_);
free_num(&_two_);
}
/* Make a copy of a number! Just increments the reference count! */
bc_num
copy_num (num)
bc_num num;
{
num->n_refs++;
return num;
}
/* Initialize a number NUM by making it a copy of zero. */
void
init_num (num)
bc_num *num;
{
*num = copy_num (_zero_);
}
/* Convert an integer VAL to a bc number NUM. */
void
int2num (num, val)
bc_num *num;
int val;
{
char buffer[30];
char *bptr, *vptr;
int ix = 1;
char neg = 0;
/* Sign. */
if (val < 0)
{
neg = 1;
val = -val;
}
/* Get things going. */
bptr = buffer;
*bptr++ = val % BASE;
val = val / BASE;
/* Extract remaining digits. */
while (val != 0)
{
*bptr++ = val % BASE;
val = val / BASE;
ix++; /* Count the digits. */
}
/* Make the number. */
free_num (num);
*num = new_num (ix, 0);
if (neg) (*num)->n_sign = MINUS;
/* Assign the digits. */
vptr = (*num)->n_value;
while (ix-- > 0)
*vptr++ = *--bptr;
}
/* Convert a number NUM to a long. The function returns only the integer
part of the number. For numbers that are too large to represent as
a long, this function returns a zero. This can be detected by checking
the NUM for zero after having a zero returned. */
long
num2long (num)
bc_num num;
{
long val;
char *nptr;
int index;
/* Extract the int value, ignore the fraction. */
val = 0;
nptr = num->n_value;
for (index=num->n_len; (index>0) && (val<=(LONG_MAX/BASE)); index--)
val = val*BASE + *nptr++;
/* Check for overflow. If overflow, return zero. */
if (index>0) val = 0;
if (val < 0) val = 0;
/* Return the value. */
if (num->n_sign == PLUS)
return (val);
else
return (-val);
}
#if 0
/* The following are some math routines for numbers. */
_PROTOTYPE(static int _do_compare, (bc_num n1, bc_num n2, int use_sign,
int ignore_last));
_PROTOTYPE(static void _rm_leading_zeros, (bc_num num));
_PROTOTYPE(static bc_num _do_add, (bc_num n1, bc_num n2, int scale_min));
_PROTOTYPE(static bc_num _do_sub, (bc_num n1, bc_num n2, int scale_min));
_PROTOTYPE(static void _one_mult, (unsigned char *num, int size, int digit,
unsigned char *result));
#endif
/* Compare two bc numbers. Return value is 0 if equal, -1 if N1 is less
than N2 and +1 if N1 is greater than N2. If USE_SIGN is false, just
compare the magnitudes. */
static int
_do_compare (n1, n2, use_sign, ignore_last)
bc_num n1, n2;
int use_sign;
int ignore_last;
{
char *n1ptr, *n2ptr;
int count;
/* First, compare signs. */
if (use_sign && n1->n_sign != n2->n_sign)
{
if (n1->n_sign == PLUS)
return (1); /* Positive N1 > Negative N2 */
else
return (-1); /* Negative N1 < Positive N1 */
}
/* Now compare the magnitude. */
if (n1->n_len != n2->n_len)
{
if (n1->n_len > n2->n_len)
{
/* Magnitude of n1 > n2. */
if (!use_sign || n1->n_sign == PLUS)
return (1);
else
return (-1);
}
else
{
/* Magnitude of n1 < n2. */
if (!use_sign || n1->n_sign == PLUS)
return (-1);
else
return (1);
}
}
/* If we get here, they have the same number of integer digits.
check the integer part and the equal length part of the fraction. */
count = n1->n_len + MIN (n1->n_scale, n2->n_scale);
n1ptr = n1->n_value;
n2ptr = n2->n_value;
while ((count > 0) && (*n1ptr == *n2ptr))
{
n1ptr++;
n2ptr++;
count--;
}
if (ignore_last && count == 1 && n1->n_scale == n2->n_scale)
return (0);
if (count != 0)
{
if (*n1ptr > *n2ptr)
{
/* Magnitude of n1 > n2. */
if (!use_sign || n1->n_sign == PLUS)
return (1);
else
return (-1);
}
else
{
/* Magnitude of n1 < n2. */
if (!use_sign || n1->n_sign == PLUS)
return (-1);
else
return (1);
}
}
/* They are equal up to the last part of the equal part of the fraction. */
if (n1->n_scale != n2->n_scale)
if (n1->n_scale > n2->n_scale)
{
for (count = n1->n_scale-n2->n_scale; count>0; count--)
if (*n1ptr++ != 0)
{
/* Magnitude of n1 > n2. */
if (!use_sign || n1->n_sign == PLUS)
return (1);
else
return (-1);
}
}
else
{
for (count = n2->n_scale-n1->n_scale; count>0; count--)
if (*n2ptr++ != 0)
{
/* Magnitude of n1 < n2. */
if (!use_sign || n1->n_sign == PLUS)
return (-1);
else
return (1);
}
}
/* They must be equal! */
return (0);
}
/* This is the "user callable" routine to compare numbers N1 and N2. */
int
bc_compare (n1, n2)
bc_num n1, n2;
{
return _do_compare (n1, n2, TRUE, FALSE);
}
/* In some places we need to check if the number NUM is zero. */
char
is_zero (num)
bc_num num;
{
int count;
char *nptr;
/* Quick check. */
if (num == _zero_) return TRUE;
/* Initialize */
count = num->n_len + num->n_scale;
nptr = num->n_value;
/* The check */
while ((count > 0) && (*nptr++ == 0)) count--;
if (count != 0)
return FALSE;
else
return TRUE;
}
/* In some places we need to check if the number is negative. */
char
is_neg (num)
bc_num num;
{
return num->n_sign == MINUS;
}
/* For many things, we may have leading zeros in a number NUM.
_rm_leading_zeros just moves the data to the correct
place and adjusts the length. */
static void
_rm_leading_zeros (num)
bc_num num;
{
int bytes;
char *dst, *src;
/* Do a quick check to see if we need to do it. */
if (*num->n_value != 0) return;
/* The first "digit" is 0, find the first non-zero digit in the second
or greater "digit" to the left of the decimal place. */
bytes = num->n_len;
src = num->n_value;
while (bytes > 1 && *src == 0) src++, bytes--;
num->n_len = bytes;
bytes += num->n_scale;
dst = num->n_value;
while (bytes-- > 0) *dst++ = *src++;
}
/* Perform addition: N1 is added to N2 and the value is
returned. The signs of N1 and N2 are ignored.
SCALE_MIN is to set the minimum scale of the result. */
static bc_num
_do_add (n1, n2, scale_min)
bc_num n1, n2;
int scale_min;
{
bc_num sum;
int sum_scale, sum_digits;
char *n1ptr, *n2ptr, *sumptr;
int carry, n1bytes, n2bytes;
int count;
/* Prepare sum. */
sum_scale = MAX (n1->n_scale, n2->n_scale);
sum_digits = MAX (n1->n_len, n2->n_len) + 1;
sum = new_num (sum_digits, MAX(sum_scale, scale_min));
/* Zero extra digits made by scale_min. */
if (scale_min > sum_scale)
{
sumptr = (char *) (sum->n_value + sum_scale + sum_digits);
for (count = scale_min - sum_scale; count > 0; count--)
*sumptr++ = 0;
}
/* Start with the fraction part. Initialize the pointers. */
n1bytes = n1->n_scale;
n2bytes = n2->n_scale;
n1ptr = (char *) (n1->n_value + n1->n_len + n1bytes - 1);
n2ptr = (char *) (n2->n_value + n2->n_len + n2bytes - 1);
sumptr = (char *) (sum->n_value + sum_scale + sum_digits - 1);
/* Add the fraction part. First copy the longer fraction.*/
if (n1bytes != n2bytes)
{
if (n1bytes > n2bytes)
while (n1bytes>n2bytes)
{ *sumptr-- = *n1ptr--; n1bytes--;}
else
while (n2bytes>n1bytes)
{ *sumptr-- = *n2ptr--; n2bytes--;}
}
/* Now add the remaining fraction part and equal size integer parts. */
n1bytes += n1->n_len;
n2bytes += n2->n_len;
carry = 0;
while ((n1bytes > 0) && (n2bytes > 0))
{
*sumptr = *n1ptr-- + *n2ptr-- + carry;
if (*sumptr > (BASE-1))
{
carry = 1;
*sumptr -= BASE;
}
else
carry = 0;
sumptr--;
n1bytes--;
n2bytes--;
}
/* Now add carry the longer integer part. */
if (n1bytes == 0)
{ n1bytes = n2bytes; n1ptr = n2ptr; }
while (n1bytes-- > 0)
{
*sumptr = *n1ptr-- + carry;
if (*sumptr > (BASE-1))
{
carry = 1;
*sumptr -= BASE;
}
else
carry = 0;
sumptr--;
}
/* Set final carry. */
if (carry == 1)
*sumptr += 1;
/* Adjust sum and return. */
_rm_leading_zeros (sum);
return sum;
}
/* Perform subtraction: N2 is subtracted from N1 and the value is
returned. The signs of N1 and N2 are ignored. Also, N1 is
assumed to be larger than N2. SCALE_MIN is the minimum scale
of the result. */
static bc_num
_do_sub (n1, n2, scale_min)
bc_num n1, n2;
int scale_min;
{
bc_num diff;
int diff_scale, diff_len;
int min_scale, min_len;
char *n1ptr, *n2ptr, *diffptr;
int borrow, count, val;
/* Allocate temporary storage. */
diff_len = MAX (n1->n_len, n2->n_len);
diff_scale = MAX (n1->n_scale, n2->n_scale);
min_len = MIN (n1->n_len, n2->n_len);
min_scale = MIN (n1->n_scale, n2->n_scale);
diff = new_num (diff_len, MAX(diff_scale, scale_min));
/* Zero extra digits made by scale_min. */
if (scale_min > diff_scale)
{
diffptr = (char *) (diff->n_value + diff_len + diff_scale);
for (count = scale_min - diff_scale; count > 0; count--)
*diffptr++ = 0;
}
/* Initialize the subtract. */
n1ptr = (char *) (n1->n_value + n1->n_len + n1->n_scale -1);
n2ptr = (char *) (n2->n_value + n2->n_len + n2->n_scale -1);
diffptr = (char *) (diff->n_value + diff_len + diff_scale -1);
/* Subtract the numbers. */
borrow = 0;
/* Take care of the longer scaled number. */
if (n1->n_scale != min_scale)
{
/* n1 has the longer scale */
for (count = n1->n_scale - min_scale; count > 0; count--)
*diffptr-- = *n1ptr--;
}
else
{
/* n2 has the longer scale */
for (count = n2->n_scale - min_scale; count > 0; count--)
{
val = - *n2ptr-- - borrow;
if (val < 0)
{
val += BASE;
borrow = 1;
}
else
borrow = 0;
*diffptr-- = val;
}
}
/* Now do the equal length scale and integer parts. */
for (count = 0; count < min_len + min_scale; count++)
{
val = *n1ptr-- - *n2ptr-- - borrow;
if (val < 0)
{
val += BASE;
borrow = 1;
}
else
borrow = 0;
*diffptr-- = val;
}
/* If n1 has more digits then n2, we now do that subtract. */
if (diff_len != min_len)
{
for (count = diff_len - min_len; count > 0; count--)
{
val = *n1ptr-- - borrow;
if (val < 0)
{
val += BASE;
borrow = 1;
}
else
borrow = 0;
*diffptr-- = val;
}
}
/* Clean up and return. */
_rm_leading_zeros (diff);
return diff;
}
/* Here is the full add routine that takes care of negative numbers.
N1 is added to N2 and the result placed into RESULT. SCALE_MIN
is the minimum scale for the result. */
void
bc_add (n1, n2, result, scale_min)
bc_num n1, n2, *result;
int scale_min;
{
bc_num sum;
int cmp_res;
int res_scale;
if (n1->n_sign == n2->n_sign)
{
sum = _do_add (n1, n2, scale_min);
sum->n_sign = n1->n_sign;
}
else
{
/* subtraction must be done. */
cmp_res = _do_compare (n1, n2, FALSE, FALSE); /* Compare magnitudes. */
switch (cmp_res)
{
case -1:
/* n1 is less than n2, subtract n1 from n2. */
sum = _do_sub (n2, n1, scale_min);
sum->n_sign = n2->n_sign;
break;
case 0:
/* They are equal! return zero with the correct scale! */
res_scale = MAX (scale_min, MAX(n1->n_scale, n2->n_scale));
sum = new_num (1, res_scale);
memset (sum->n_value, 0, res_scale+1);
break;
case 1:
/* n2 is less than n1, subtract n2 from n1. */
sum = _do_sub (n1, n2, scale_min);
sum->n_sign = n1->n_sign;
}
}
/* Clean up and return. */
free_num (result);
*result = sum;
}
/* Here is the full subtract routine that takes care of negative numbers.
N2 is subtracted from N1 and the result placed in RESULT. SCALE_MIN
is the minimum scale for the result. */
void
bc_sub (n1, n2, result, scale_min)
bc_num n1, n2, *result;
int scale_min;
{
bc_num diff;
int cmp_res;
int res_scale;
if (n1->n_sign != n2->n_sign)
{
diff = _do_add (n1, n2, scale_min);
diff->n_sign = n1->n_sign;
}
else
{
/* subtraction must be done. */
cmp_res = _do_compare (n1, n2, FALSE, FALSE); /* Compare magnitudes. */
switch (cmp_res)
{
case -1:
/* n1 is less than n2, subtract n1 from n2. */
diff = _do_sub (n2, n1, scale_min);
diff->n_sign = (n2->n_sign == PLUS ? MINUS : PLUS);
break;
case 0:
/* They are equal! return zero! */
res_scale = MAX (scale_min, MAX(n1->n_scale, n2->n_scale));
diff = new_num (1, res_scale);
memset (diff->n_value, 0, res_scale+1);
break;
case 1:
/* n2 is less than n1, subtract n2 from n1. */
diff = _do_sub (n1, n2, scale_min);
diff->n_sign = n1->n_sign;
break;
}
}
/* Clean up and return. */
free_num (result);
*result = diff;
}
/* The multiply routine. N2 time N1 is put int PROD with the scale of
the result being MIN(N2 scale+N1 scale, MAX (SCALE, N2 scale, N1 scale)).
*/
void
bc_multiply (n1, n2, prod, scale)
bc_num n1, n2, *prod;
int scale;
{
bc_num pval; /* For the working storage. */
char *n1ptr, *n2ptr, *pvptr; /* Work pointers. */
char *n1end, *n2end; /* To the end of n1 and n2. */
int indx;
int len1, len2, total_digits;
long sum;
int full_scale, prod_scale;
int toss;
/* Initialize things. */
len1 = n1->n_len + n1->n_scale;
len2 = n2->n_len + n2->n_scale;
total_digits = len1 + len2;
full_scale = n1->n_scale + n2->n_scale;
prod_scale = MIN(full_scale,MAX(scale,MAX(n1->n_scale,n2->n_scale)));
toss = full_scale - prod_scale;
pval = new_num (total_digits-full_scale, prod_scale);
pval->n_sign = ( n1->n_sign == n2->n_sign ? PLUS : MINUS );
n1end = (char *) (n1->n_value + len1 - 1);
n2end = (char *) (n2->n_value + len2 - 1);
pvptr = (char *) (pval->n_value + total_digits - toss - 1);
sum = 0;
/* Here are the loops... */
for (indx = 0; indx < toss; indx++)
{
n1ptr = (char *) (n1end - MAX(0, indx-len2+1));
n2ptr = (char *) (n2end - MIN(indx, len2-1));
while ((n1ptr >= n1->n_value) && (n2ptr <= n2end))
sum += *n1ptr-- * *n2ptr++;
sum = sum / BASE;
}
for ( ; indx < total_digits-1; indx++)
{
n1ptr = (char *) (n1end - MAX(0, indx-len2+1));
n2ptr = (char *) (n2end - MIN(indx, len2-1));
while ((n1ptr >= n1->n_value) && (n2ptr <= n2end))
sum += *n1ptr-- * *n2ptr++;
*pvptr-- = sum % BASE;
sum = sum / BASE;
}
/*FIXME does this typecast hurt us? Put here to
disable warning in windows.*/
*pvptr-- = (char)sum;
/* Assign to prod and clean up the number. */
free_num (prod);
*prod = pval;
_rm_leading_zeros (*prod);
if (is_zero (*prod))
(*prod)->n_sign = PLUS;
}
/* Some utility routines for the divide: First a one digit multiply.
NUM (with SIZE digits) is multiplied by DIGIT and the result is
placed into RESULT. It is written so that NUM and RESULT can be
the same pointers. */
static void
_one_mult (num, size, digit, result)
unsigned char *num;
int size, digit;
unsigned char *result;
{
int carry, value;
unsigned char *nptr, *rptr;
if (digit == 0)
memset (result, 0, size);
else
{
if (digit == 1)
memcpy (result, num, size);
else
{
/* Initialize */
nptr = (unsigned char *) (num+size-1);
rptr = (unsigned char *) (result+size-1);
carry = 0;
while (size-- > 0)
{
value = *nptr-- * digit + carry;
*rptr-- = value % BASE;
carry = value / BASE;
}
if (carry != 0) *rptr = carry;
}
}
}
/* The full division routine. This computes N1 / N2. It returns
0 if the division is ok and the result is in QUOT. The number of
digits after the decimal point is SCALE. It returns -1 if division
by zero is tried. The algorithm is found in Knuth Vol 2. p237. */
int
bc_divide (n1, n2, quot, scale)
bc_num n1, n2, *quot;
int scale;
{
bc_num qval;
unsigned char *num1, *num2;
unsigned char *ptr1, *ptr2, *n2ptr, *qptr;
int scale1, val;
unsigned int len1, len2, scale2, qdigits, extra, count;
unsigned int qdig, qguess, borrow, carry;
unsigned char *mval;
char zero;
unsigned int norm;
/* Test for divide by zero. */
if (is_zero (n2)) return -1;
/* Test for divide by 1. If it is we must truncate. */
if (n2->n_scale == 0)
{
if (n2->n_len == 1 && *n2->n_value == 1)
{
qval = new_num (n1->n_len, scale);
qval->n_sign = (n1->n_sign == n2->n_sign ? PLUS : MINUS);
memset (&qval->n_value[n1->n_len],0,scale);
memcpy (qval->n_value, n1->n_value,
n1->n_len + MIN(n1->n_scale,scale));
free_num (quot);
*quot = qval;
}
}
/* Set up the divide. Move the decimal point on n1 by n2's scale.
Remember, zeros on the end of num2 are wasted effort for dividing. */
scale2 = n2->n_scale;
n2ptr = (unsigned char *) n2->n_value+n2->n_len+scale2-1;
while ((scale2 > 0) && (*n2ptr-- == 0)) scale2--;
len1 = n1->n_len + scale2;
scale1 = n1->n_scale - scale2;
if (scale1 < scale)
extra = scale - scale1;
else
extra = 0;
num1 = (unsigned char *) emalloc (n1->n_len+n1->n_scale+extra+2);
if (num1 == NULL) out_of_memory();
memset (num1, 0, n1->n_len+n1->n_scale+extra+2);
memcpy (num1+1, n1->n_value, n1->n_len+n1->n_scale);
len2 = n2->n_len + scale2;
num2 = (unsigned char *) emalloc (len2+1);
if (num2 == NULL) out_of_memory();
memcpy (num2, n2->n_value, len2);
*(num2+len2) = 0;
n2ptr = num2;
while (*n2ptr == 0)
{
n2ptr++;
len2--;
}
/* Calculate the number of quotient digits. */
if (len2 > len1+scale)
{
qdigits = scale+1;
zero = TRUE;
}
else
{
zero = FALSE;
if (len2>len1)
qdigits = scale+1; /* One for the zero integer part. */
else
qdigits = len1-len2+scale+1;
}
/* Allocate and zero the storage for the quotient. */
qval = new_num (qdigits-scale,scale);
memset (qval->n_value, 0, qdigits);
/* Allocate storage for the temporary storage mval. */
mval = (unsigned char *) emalloc (len2+1);
if (mval == NULL) out_of_memory ();
/* Now for the full divide algorithm. */
if (!zero)
{
/* Normalize */
norm = 10 / ((int)*n2ptr + 1);
if (norm != 1)
{
_one_mult (num1, len1+scale1+extra+1, norm, num1);
_one_mult (n2ptr, len2, norm, n2ptr);
}
/* Initialize divide loop. */
qdig = 0;
if (len2 > len1)
qptr = (unsigned char *) qval->n_value+len2-len1;
else
qptr = (unsigned char *) qval->n_value;
/* Loop */
while (qdig <= len1+scale-len2)
{
/* Calculate the quotient digit guess. */
if (*n2ptr == num1[qdig])
qguess = 9;
else
qguess = (num1[qdig]*10 + num1[qdig+1]) / *n2ptr;
/* Test qguess. */
if (n2ptr[1]*qguess >
(num1[qdig]*10 + num1[qdig+1] - *n2ptr*qguess)*10
+ num1[qdig+2])
{
qguess--;
/* And again. */
if (n2ptr[1]*qguess >
(num1[qdig]*10 + num1[qdig+1] - *n2ptr*qguess)*10
+ num1[qdig+2])
qguess--;
}
/* Multiply and subtract. */
borrow = 0;
if (qguess != 0)
{
*mval = 0;
_one_mult (n2ptr, len2, qguess, mval+1);
ptr1 = (unsigned char *) num1+qdig+len2;
ptr2 = (unsigned char *) mval+len2;
for (count = 0; count < len2+1; count++)
{
val = (int) *ptr1 - (int) *ptr2-- - borrow;
if (val < 0)
{
val += 10;
borrow = 1;
}
else
borrow = 0;
*ptr1-- = val;
}
}
/* Test for negative result. */
if (borrow == 1)
{
qguess--;
ptr1 = (unsigned char *) num1+qdig+len2;
ptr2 = (unsigned char *) n2ptr+len2-1;
carry = 0;
for (count = 0; count < len2; count++)
{
val = (int) *ptr1 + (int) *ptr2-- + carry;
if (val > 9)
{
val -= 10;
carry = 1;
}
else
carry = 0;
*ptr1-- = val;
}
if (carry == 1) *ptr1 = (*ptr1 + 1) % 10;
}
/* We now know the quotient digit. */
*qptr++ = qguess;
qdig++;
}
}
/* Clean up and return the number. */
qval->n_sign = ( n1->n_sign == n2->n_sign ? PLUS : MINUS );
if (is_zero (qval)) qval->n_sign = PLUS;
_rm_leading_zeros (qval);
free_num (quot);
*quot = qval;
/* Clean up temporary storage. */
efree (mval);
efree (num1);
efree (num2);
return 0; /* Everything is OK. */
}
/* Division *and* modulo for numbers. This computes both NUM1 / NUM2 and
NUM1 % NUM2 and puts the results in QUOT and REM, except that if QUOT
is NULL then that store will be omitted.
*/
int
bc_divmod (num1, num2, quot, rem, scale)