greenplumn numeric 源码
greenplumn numeric 代码
文件路径：/src/interfaces/ecpg/pgtypeslib/numeric.c
/* src/interfaces/ecpg/pgtypeslib/numeric.c */
#include "postgres_fe.h"
#include <ctype.h>
#include <float.h>
#include <limits.h>
#include "pgtypeslib_extern.h"
#include "pgtypes_error.h"
#define Max(x, y) ((x) > (y) ? (x) : (y))
#define Min(x, y) ((x) < (y) ? (x) : (y))
#define init_var(v) memset(v,0,sizeof(numeric))
#define digitbuf_alloc(size) ((NumericDigit *) pgtypes_alloc(size))
#define digitbuf_free(buf) \
do { \
if ((buf) != NULL) \
free(buf); \
} while (0)
#include "pgtypes_numeric.h"
#if 0
/* ----------
* apply_typmod() -
*
* Do bounds checking and rounding according to the attributes
* typmod field.
* ----------
*/
static int
apply_typmod(numeric *var, long typmod)
{
int precision;
int scale;
int maxweight;
int i;
/* Do nothing if we have a default typmod (-1) */
if (typmod < (long) (VARHDRSZ))
return 0;
typmod -= VARHDRSZ;
precision = (typmod >> 16) & 0xffff;
scale = typmod & 0xffff;
maxweight = precision - scale;
/* Round to target scale */
i = scale + var->weight + 1;
if (i >= 0 && var->ndigits > i)
{
int carry = (var->digits[i] > 4) ? 1 : 0;
var->ndigits = i;
while (carry)
{
carry += var->digits[--i];
var->digits[i] = carry % 10;
carry /= 10;
}
if (i < 0)
{
var->digits--;
var->ndigits++;
var->weight++;
}
}
else
var->ndigits = Max(0, Min(i, var->ndigits));
/*
* Check for overflow - note we can't do this before rounding, because
* rounding could raise the weight. Also note that the var's weight could
* be inflated by leading zeroes, which will be stripped before storage
* but perhaps might not have been yet. In any case, we must recognize a
* true zero, whose weight doesn't mean anything.
*/
if (var->weight >= maxweight)
{
/* Determine true weight; and check for all-zero result */
int tweight = var->weight;
for (i = 0; i < var->ndigits; i++)
{
if (var->digits[i])
break;
tweight--;
}
if (tweight >= maxweight && i < var->ndigits)
{
errno = PGTYPES_NUM_OVERFLOW;
return -1;
}
}
var->rscale = scale;
var->dscale = scale;
return 0;
}
#endif
/* ----------
* alloc_var() -
*
* Allocate a digit buffer of ndigits digits (plus a spare digit for rounding)
* ----------
*/
static int
alloc_var(numeric *var, int ndigits)
{
digitbuf_free(var->buf);
var->buf = digitbuf_alloc(ndigits + 1);
if (var->buf == NULL)
return -1;
var->buf[0] = 0;
var->digits = var->buf + 1;
var->ndigits = ndigits;
return 0;
}
numeric *
PGTYPESnumeric_new(void)
{
numeric *var;
if ((var = (numeric *) pgtypes_alloc(sizeof(numeric))) == NULL)
return NULL;
if (alloc_var(var, 0) < 0)
{
free(var);
return NULL;
}
return var;
}
decimal *
PGTYPESdecimal_new(void)
{
decimal *var;
if ((var = (decimal *) pgtypes_alloc(sizeof(decimal))) == NULL)
return NULL;
memset(var, 0, sizeof(decimal));
return var;
}
/* ----------
* set_var_from_str()
*
* Parse a string and put the number into a variable
* ----------
*/
static int
set_var_from_str(char *str, char **ptr, numeric *dest)
{
bool have_dp = false;
int i = 0;
errno = 0;
*ptr = str;
while (*(*ptr))
{
if (!isspace((unsigned char) *(*ptr)))
break;
(*ptr)++;
}
if (pg_strncasecmp(*ptr, "NaN", 3) == 0)
{
*ptr += 3;
dest->sign = NUMERIC_NAN;
/* Should be nothing left but spaces */
while (*(*ptr))
{
if (!isspace((unsigned char) *(*ptr)))
{
errno = PGTYPES_NUM_BAD_NUMERIC;
return -1;
}
(*ptr)++;
}
return 0;
}
if (alloc_var(dest, strlen((*ptr))) < 0)
return -1;
dest->weight = -1;
dest->dscale = 0;
dest->sign = NUMERIC_POS;
switch (*(*ptr))
{
case '+':
dest->sign = NUMERIC_POS;
(*ptr)++;
break;
case '-':
dest->sign = NUMERIC_NEG;
(*ptr)++;
break;
}
if (*(*ptr) == '.')
{
have_dp = true;
(*ptr)++;
}
if (!isdigit((unsigned char) *(*ptr)))
{
errno = PGTYPES_NUM_BAD_NUMERIC;
return -1;
}
while (*(*ptr))
{
if (isdigit((unsigned char) *(*ptr)))
{
dest->digits[i++] = *(*ptr)++ - '0';
if (!have_dp)
dest->weight++;
else
dest->dscale++;
}
else if (*(*ptr) == '.')
{
if (have_dp)
{
errno = PGTYPES_NUM_BAD_NUMERIC;
return -1;
}
have_dp = true;
(*ptr)++;
}
else
break;
}
dest->ndigits = i;
/* Handle exponent, if any */
if (*(*ptr) == 'e' || *(*ptr) == 'E')
{
long exponent;
char *endptr;
(*ptr)++;
exponent = strtol(*ptr, &endptr, 10);
if (endptr == (*ptr))
{
errno = PGTYPES_NUM_BAD_NUMERIC;
return -1;
}
(*ptr) = endptr;
if (exponent >= INT_MAX / 2 || exponent <= -(INT_MAX / 2))
{
errno = PGTYPES_NUM_BAD_NUMERIC;
return -1;
}
dest->weight += (int) exponent;
dest->dscale -= (int) exponent;
if (dest->dscale < 0)
dest->dscale = 0;
}
/* Should be nothing left but spaces */
while (*(*ptr))
{
if (!isspace((unsigned char) *(*ptr)))
{
errno = PGTYPES_NUM_BAD_NUMERIC;
return -1;
}
(*ptr)++;
}
/* Strip any leading zeroes */
while (dest->ndigits > 0 && *(dest->digits) == 0)
{
(dest->digits)++;
(dest->weight)--;
(dest->ndigits)--;
}
if (dest->ndigits == 0)
dest->weight = 0;
dest->rscale = dest->dscale;
return 0;
}
/* ----------
* get_str_from_var() -
*
* Convert a var to text representation (guts of numeric_out).
* CAUTION: var's contents may be modified by rounding!
* ----------
*/
static char *
get_str_from_var(numeric *var, int dscale)
{
char *str;
char *cp;
int i;
int d;
if (var->sign == NUMERIC_NAN)
{
str = (char *) pgtypes_alloc(4);
if (str == NULL)
return NULL;
sprintf(str, "NaN");
return str;
}
/*
* Check if we must round up before printing the value and do so.
*/
i = dscale + var->weight + 1;
if (i >= 0 && var->ndigits > i)
{
int carry = (var->digits[i] > 4) ? 1 : 0;
var->ndigits = i;
while (carry)
{
carry += var->digits[--i];
var->digits[i] = carry % 10;
carry /= 10;
}
if (i < 0)
{
var->digits--;
var->ndigits++;
var->weight++;
}
}
else
var->ndigits = Max(0, Min(i, var->ndigits));
/*
* Allocate space for the result
*/
if ((str = (char *) pgtypes_alloc(Max(0, dscale) + Max(0, var->weight) + 4)) == NULL)
return NULL;
cp = str;
/*
* Output a dash for negative values
*/
if (var->sign == NUMERIC_NEG)
*cp++ = '-';
/*
* Output all digits before the decimal point
*/
i = Max(var->weight, 0);
d = 0;
while (i >= 0)
{
if (i <= var->weight && d < var->ndigits)
*cp++ = var->digits[d++] + '0';
else
*cp++ = '0';
i--;
}
/*
* If requested, output a decimal point and all the digits that follow it.
*/
if (dscale > 0)
{
*cp++ = '.';
while (i >= -dscale)
{
if (i <= var->weight && d < var->ndigits)
*cp++ = var->digits[d++] + '0';
else
*cp++ = '0';
i--;
}
}
/*
* terminate the string and return it
*/
*cp = '\0';
return str;
}
numeric *
PGTYPESnumeric_from_asc(char *str, char **endptr)
{
numeric *value = (numeric *) pgtypes_alloc(sizeof(numeric));
int ret;
char *realptr;
char **ptr = (endptr != NULL) ? endptr : &realptr;
if (!value)
return NULL;
ret = set_var_from_str(str, ptr, value);
if (ret)
{
PGTYPESnumeric_free(value);
return NULL;
}
return value;
}
char *
PGTYPESnumeric_to_asc(numeric *num, int dscale)
{
numeric *numcopy = PGTYPESnumeric_new();
char *s;
if (numcopy == NULL)
return NULL;
if (PGTYPESnumeric_copy(num, numcopy) < 0)
{
PGTYPESnumeric_free(numcopy);
return NULL;
}
if (dscale < 0)
dscale = num->dscale;
/* get_str_from_var may change its argument */
s = get_str_from_var(numcopy, dscale);
PGTYPESnumeric_free(numcopy);
return s;
}
/* ----------
* zero_var() -
*
* Set a variable to ZERO.
* Note: rscale and dscale are not touched.
* ----------
*/
static void
zero_var(numeric *var)
{
digitbuf_free(var->buf);
var->buf = NULL;
var->digits = NULL;
var->ndigits = 0;
var->weight = 0; /* by convention; doesn't really matter */
var->sign = NUMERIC_POS; /* anything but NAN... */
}
void
PGTYPESnumeric_free(numeric *var)
{
digitbuf_free(var->buf);
free(var);
}
void
PGTYPESdecimal_free(decimal *var)
{
free(var);
}
/* ----------
* cmp_abs() -
*
* Compare the absolute values of var1 and var2
* Returns: -1 for ABS(var1) < ABS(var2)
* 0 for ABS(var1) == ABS(var2)
* 1 for ABS(var1) > ABS(var2)
* ----------
*/
static int
cmp_abs(numeric *var1, numeric *var2)
{
int i1 = 0;
int i2 = 0;
int w1 = var1->weight;
int w2 = var2->weight;
int stat;
while (w1 > w2 && i1 < var1->ndigits)
{
if (var1->digits[i1++] != 0)
return 1;
w1--;
}
while (w2 > w1 && i2 < var2->ndigits)
{
if (var2->digits[i2++] != 0)
return -1;
w2--;
}
if (w1 == w2)
{
while (i1 < var1->ndigits && i2 < var2->ndigits)
{
stat = var1->digits[i1++] - var2->digits[i2++];
if (stat)
{
if (stat > 0)
return 1;
return -1;
}
}
}
while (i1 < var1->ndigits)
{
if (var1->digits[i1++] != 0)
return 1;
}
while (i2 < var2->ndigits)
{
if (var2->digits[i2++] != 0)
return -1;
}
return 0;
}
/* ----------
* add_abs() -
*
* Add the absolute values of two variables into result.
* result might point to one of the operands without danger.
* ----------
*/
static int
add_abs(numeric *var1, numeric *var2, numeric *result)
{
NumericDigit *res_buf;
NumericDigit *res_digits;
int res_ndigits;
int res_weight;
int res_rscale;
int res_dscale;
int i,
i1,
i2;
int carry = 0;
/* copy these values into local vars for speed in inner loop */
int var1ndigits = var1->ndigits;
int var2ndigits = var2->ndigits;
NumericDigit *var1digits = var1->digits;
NumericDigit *var2digits = var2->digits;
res_weight = Max(var1->weight, var2->weight) + 1;
res_rscale = Max(var1->rscale, var2->rscale);
res_dscale = Max(var1->dscale, var2->dscale);
res_ndigits = res_rscale + res_weight + 1;
if (res_ndigits <= 0)
res_ndigits = 1;
if ((res_buf = digitbuf_alloc(res_ndigits)) == NULL)
return -1;
res_digits = res_buf;
i1 = res_rscale + var1->weight + 1;
i2 = res_rscale + var2->weight + 1;
for (i = res_ndigits - 1; i >= 0; i--)
{
i1--;
i2--;
if (i1 >= 0 && i1 < var1ndigits)
carry += var1digits[i1];
if (i2 >= 0 && i2 < var2ndigits)
carry += var2digits[i2];
if (carry >= 10)
{
res_digits[i] = carry - 10;
carry = 1;
}
else
{
res_digits[i] = carry;
carry = 0;
}
}
while (res_ndigits > 0 && *res_digits == 0)
{
res_digits++;
res_weight--;
res_ndigits--;
}
while (res_ndigits > 0 && res_digits[res_ndigits - 1] == 0)
res_ndigits--;
if (res_ndigits == 0)
res_weight = 0;
digitbuf_free(result->buf);
result->ndigits = res_ndigits;
result->buf = res_buf;
result->digits = res_digits;
result->weight = res_weight;
result->rscale = res_rscale;
result->dscale = res_dscale;
return 0;
}
/* ----------
* sub_abs() -
*
* Subtract the absolute value of var2 from the absolute value of var1
* and store in result. result might point to one of the operands
* without danger.
*
* ABS(var1) MUST BE GREATER OR EQUAL ABS(var2) !!!
* ----------
*/
static int
sub_abs(numeric *var1, numeric *var2, numeric *result)
{
NumericDigit *res_buf;
NumericDigit *res_digits;
int res_ndigits;
int res_weight;
int res_rscale;
int res_dscale;
int i,
i1,
i2;
int borrow = 0;
/* copy these values into local vars for speed in inner loop */
int var1ndigits = var1->ndigits;
int var2ndigits = var2->ndigits;
NumericDigit *var1digits = var1->digits;
NumericDigit *var2digits = var2->digits;
res_weight = var1->weight;
res_rscale = Max(var1->rscale, var2->rscale);
res_dscale = Max(var1->dscale, var2->dscale);
res_ndigits = res_rscale + res_weight + 1;
if (res_ndigits <= 0)
res_ndigits = 1;
if ((res_buf = digitbuf_alloc(res_ndigits)) == NULL)
return -1;
res_digits = res_buf;
i1 = res_rscale + var1->weight + 1;
i2 = res_rscale + var2->weight + 1;
for (i = res_ndigits - 1; i >= 0; i--)
{
i1--;
i2--;
if (i1 >= 0 && i1 < var1ndigits)
borrow += var1digits[i1];
if (i2 >= 0 && i2 < var2ndigits)
borrow -= var2digits[i2];
if (borrow < 0)
{
res_digits[i] = borrow + 10;
borrow = -1;
}
else
{
res_digits[i] = borrow;
borrow = 0;
}
}
while (res_ndigits > 0 && *res_digits == 0)
{
res_digits++;
res_weight--;
res_ndigits--;
}
while (res_ndigits > 0 && res_digits[res_ndigits - 1] == 0)
res_ndigits--;
if (res_ndigits == 0)
res_weight = 0;
digitbuf_free(result->buf);
result->ndigits = res_ndigits;
result->buf = res_buf;
result->digits = res_digits;
result->weight = res_weight;
result->rscale = res_rscale;
result->dscale = res_dscale;
return 0;
}
/* ----------
* add_var() -
*
* Full version of add functionality on variable level (handling signs).
* result might point to one of the operands too without danger.
* ----------
*/
int
PGTYPESnumeric_add(numeric *var1, numeric *var2, numeric *result)
{
/*
* Decide on the signs of the two variables what to do
*/
if (var1->sign == NUMERIC_POS)
{
if (var2->sign == NUMERIC_POS)
{
/*
* Both are positive result = +(ABS(var1) + ABS(var2))
*/
if (add_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_POS;
}
else
{
/*
* var1 is positive, var2 is negative Must compare absolute values
*/
switch (cmp_abs(var1, var2))
{
case 0:
/* ----------
* ABS(var1) == ABS(var2)
* result = ZERO
* ----------
*/
zero_var(result);
result->rscale = Max(var1->rscale, var2->rscale);
result->dscale = Max(var1->dscale, var2->dscale);
break;
case 1:
/* ----------
* ABS(var1) > ABS(var2)
* result = +(ABS(var1) - ABS(var2))
* ----------
*/
if (sub_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_POS;
break;
case -1:
/* ----------
* ABS(var1) < ABS(var2)
* result = -(ABS(var2) - ABS(var1))
* ----------
*/
if (sub_abs(var2, var1, result) != 0)
return -1;
result->sign = NUMERIC_NEG;
break;
}
}
}
else
{
if (var2->sign == NUMERIC_POS)
{
/* ----------
* var1 is negative, var2 is positive
* Must compare absolute values
* ----------
*/
switch (cmp_abs(var1, var2))
{
case 0:
/* ----------
* ABS(var1) == ABS(var2)
* result = ZERO
* ----------
*/
zero_var(result);
result->rscale = Max(var1->rscale, var2->rscale);
result->dscale = Max(var1->dscale, var2->dscale);
break;
case 1:
/* ----------
* ABS(var1) > ABS(var2)
* result = -(ABS(var1) - ABS(var2))
* ----------
*/
if (sub_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_NEG;
break;
case -1:
/* ----------
* ABS(var1) < ABS(var2)
* result = +(ABS(var2) - ABS(var1))
* ----------
*/
if (sub_abs(var2, var1, result) != 0)
return -1;
result->sign = NUMERIC_POS;
break;
}
}
else
{
/* ----------
* Both are negative
* result = -(ABS(var1) + ABS(var2))
* ----------
*/
if (add_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_NEG;
}
}
return 0;
}
/* ----------
* sub_var() -
*
* Full version of sub functionality on variable level (handling signs).
* result might point to one of the operands too without danger.
* ----------
*/
int
PGTYPESnumeric_sub(numeric *var1, numeric *var2, numeric *result)
{
/*
* Decide on the signs of the two variables what to do
*/
if (var1->sign == NUMERIC_POS)
{
if (var2->sign == NUMERIC_NEG)
{
/* ----------
* var1 is positive, var2 is negative
* result = +(ABS(var1) + ABS(var2))
* ----------
*/
if (add_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_POS;
}
else
{
/* ----------
* Both are positive
* Must compare absolute values
* ----------
*/
switch (cmp_abs(var1, var2))
{
case 0:
/* ----------
* ABS(var1) == ABS(var2)
* result = ZERO
* ----------
*/
zero_var(result);
result->rscale = Max(var1->rscale, var2->rscale);
result->dscale = Max(var1->dscale, var2->dscale);
break;
case 1:
/* ----------
* ABS(var1) > ABS(var2)
* result = +(ABS(var1) - ABS(var2))
* ----------
*/
if (sub_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_POS;
break;
case -1:
/* ----------
* ABS(var1) < ABS(var2)
* result = -(ABS(var2) - ABS(var1))
* ----------
*/
if (sub_abs(var2, var1, result) != 0)
return -1;
result->sign = NUMERIC_NEG;
break;
}
}
}
else
{
if (var2->sign == NUMERIC_NEG)
{
/* ----------
* Both are negative
* Must compare absolute values
* ----------
*/
switch (cmp_abs(var1, var2))
{
case 0:
/* ----------
* ABS(var1) == ABS(var2)
* result = ZERO
* ----------
*/
zero_var(result);
result->rscale = Max(var1->rscale, var2->rscale);
result->dscale = Max(var1->dscale, var2->dscale);
break;
case 1:
/* ----------
* ABS(var1) > ABS(var2)
* result = -(ABS(var1) - ABS(var2))
* ----------
*/
if (sub_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_NEG;
break;
case -1:
/* ----------
* ABS(var1) < ABS(var2)
* result = +(ABS(var2) - ABS(var1))
* ----------
*/
if (sub_abs(var2, var1, result) != 0)
return -1;
result->sign = NUMERIC_POS;
break;
}
}
else
{
/* ----------
* var1 is negative, var2 is positive
* result = -(ABS(var1) + ABS(var2))
* ----------
*/
if (add_abs(var1, var2, result) != 0)
return -1;
result->sign = NUMERIC_NEG;
}
}
return 0;
}
/* ----------
* mul_var() -
*
* Multiplication on variable level. Product of var1 * var2 is stored
* in result. Accuracy of result is determined by global_rscale.
* ----------
*/
int
PGTYPESnumeric_mul(numeric *var1, numeric *var2, numeric *result)
{
NumericDigit *res_buf;
NumericDigit *res_digits;
int res_ndigits;
int res_weight;
int res_sign;
int i,
ri,
i1,
i2;
long sum = 0;
int global_rscale = var1->rscale + var2->rscale;
res_weight = var1->weight + var2->weight + 2;
res_ndigits = var1->ndigits + var2->ndigits + 1;
if (var1->sign == var2->sign)
res_sign = NUMERIC_POS;
else
res_sign = NUMERIC_NEG;
if ((res_buf = digitbuf_alloc(res_ndigits)) == NULL)
return -1;
res_digits = res_buf;
memset(res_digits, 0, res_ndigits);
ri = res_ndigits;
for (i1 = var1->ndigits - 1; i1 >= 0; i1--)
{
sum = 0;
i = --ri;
for (i2 = var2->ndigits - 1; i2 >= 0; i2--)
{
sum += res_digits[i] + var1->digits[i1] * var2->digits[i2];
res_digits[i--] = sum % 10;
sum /= 10;
}
res_digits[i] = sum;
}
i = res_weight + global_rscale + 2;
if (i >= 0 && i < res_ndigits)
{
sum = (res_digits[i] > 4) ? 1 : 0;
res_ndigits = i;
i--;
while (sum)
{
sum += res_digits[i];
res_digits[i--] = sum % 10;
sum /= 10;
}
}
while (res_ndigits > 0 && *res_digits == 0)
{
res_digits++;
res_weight--;
res_ndigits--;
}
while (res_ndigits > 0 && res_digits[res_ndigits - 1] == 0)
res_ndigits--;
if (res_ndigits == 0)
{
res_sign = NUMERIC_POS;
res_weight = 0;
}
digitbuf_free(result->buf);
result->buf = res_buf;
result->digits = res_digits;
result->ndigits = res_ndigits;
result->weight = res_weight;
result->rscale = global_rscale;
result->sign = res_sign;
result->dscale = var1->dscale + var2->dscale;
return 0;
}
/*
* Default scale selection for division
*
* Returns the appropriate display scale for the division result,
* and sets global_rscale to the result scale to use during div_var.
*
* Note that this must be called before div_var.
*/
static int
select_div_scale(numeric *var1, numeric *var2, int *rscale)
{
int weight1,
weight2,
qweight,
i;
NumericDigit firstdigit1,
firstdigit2;
int res_dscale;
/*
* The result scale of a division isn't specified in any SQL standard. For
* PostgreSQL we select a display scale that will give at least
* NUMERIC_MIN_SIG_DIGITS significant digits, so that numeric gives a
* result no less accurate than float8; but use a scale not less than
* either input's display scale.
*/
/* Get the actual (normalized) weight and first digit of each input */
weight1 = 0; /* values to use if var1 is zero */
firstdigit1 = 0;
for (i = 0; i < var1->ndigits; i++)
{
firstdigit1 = var1->digits[i];
if (firstdigit1 != 0)
{
weight1 = var1->weight - i;
break;
}
}
weight2 = 0; /* values to use if var2 is zero */
firstdigit2 = 0;
for (i = 0; i < var2->ndigits; i++)
{
firstdigit2 = var2->digits[i];
if (firstdigit2 != 0)
{
weight2 = var2->weight - i;
break;
}
}
/*
* Estimate weight of quotient. If the two first digits are equal, we
* can't be sure, but assume that var1 is less than var2.
*/
qweight = weight1 - weight2;
if (firstdigit1 <= firstdigit2)
qweight--;
/* Select display scale */
res_dscale = NUMERIC_MIN_SIG_DIGITS - qweight;
res_dscale = Max(res_dscale, var1->dscale);
res_dscale = Max(res_dscale, var2->dscale);
res_dscale = Max(res_dscale, NUMERIC_MIN_DISPLAY_SCALE);
res_dscale = Min(res_dscale, NUMERIC_MAX_DISPLAY_SCALE);
/* Select result scale */
*rscale = res_dscale + 4;
return res_dscale;
}
int
PGTYPESnumeric_div(numeric *var1, numeric *var2, numeric *result)
{
NumericDigit *res_digits;
int res_ndigits;
int res_sign;
int res_weight;
numeric dividend;
numeric divisor[10];
int ndigits_tmp;
int weight_tmp;
int rscale_tmp;
int ri;
int i;
long guess;
long first_have;
long first_div;
int first_nextdigit;
int stat = 0;
int rscale;
int res_dscale = select_div_scale(var1, var2, &rscale);
int err = -1;
NumericDigit *tmp_buf;
/*
* First of all division by zero check
*/
ndigits_tmp = var2->ndigits + 1;
if (ndigits_tmp == 1)
{
errno = PGTYPES_NUM_DIVIDE_ZERO;
return -1;
}
/*
* Determine the result sign, weight and number of digits to calculate
*/
if (var1->sign == var2->sign)
res_sign = NUMERIC_POS;
else
res_sign = NUMERIC_NEG;
res_weight = var1->weight - var2->weight + 1;
res_ndigits = rscale + res_weight;
if (res_ndigits <= 0)
res_ndigits = 1;
/*
* Now result zero check
*/
if (var1->ndigits == 0)
{
zero_var(result);
result->rscale = rscale;
return 0;
}
/*
* Initialize local variables
*/
init_var(÷nd);
for (i = 1; i < 10; i++)
init_var(&divisor[i]);
/*
* Make a copy of the divisor which has one leading zero digit
*/
divisor[1].ndigits = ndigits_tmp;
divisor[1].rscale = var2->ndigits;
divisor[1].sign = NUMERIC_POS;
divisor[1].buf = digitbuf_alloc(ndigits_tmp);
if (divisor[1].buf == NULL)
goto done;
divisor[1].digits = divisor[1].buf;
divisor[1].digits[0] = 0;
memcpy(&(divisor[1].digits[1]), var2->digits, ndigits_tmp - 1);
/*
* Make a copy of the dividend
*/
dividend.ndigits = var1->ndigits;
dividend.weight = 0;
dividend.rscale = var1->ndigits;
dividend.sign = NUMERIC_POS;
dividend.buf = digitbuf_alloc(var1->ndigits);
if (dividend.buf == NULL)
goto done;
dividend.digits = dividend.buf;
memcpy(dividend.digits, var1->digits, var1->ndigits);
/*
* Setup the result. Do the allocation in a temporary buffer first, so we
* don't free result->buf unless we have successfully allocated a buffer
* to replace it with.
*/
tmp_buf = digitbuf_alloc(res_ndigits + 2);
if (tmp_buf == NULL)
goto done;
digitbuf_free(result->buf);
result->buf = tmp_buf;
res_digits = result->buf;
result->digits = res_digits;
result->ndigits = res_ndigits;
result->weight = res_weight;
result->rscale = rscale;
result->sign = res_sign;
res_digits[0] = 0;
first_div = divisor[1].digits[1] * 10;
if (ndigits_tmp > 2)
first_div += divisor[1].digits[2];
first_have = 0;
first_nextdigit = 0;
weight_tmp = 1;
rscale_tmp = divisor[1].rscale;
for (ri = 0; ri <= res_ndigits; ri++)
{
first_have = first_have * 10;
if (first_nextdigit >= 0 && first_nextdigit < dividend.ndigits)
first_have += dividend.digits[first_nextdigit];
first_nextdigit++;
guess = (first_have * 10) / first_div + 1;
if (guess > 9)
guess = 9;
while (guess > 0)
{
if (divisor[guess].buf == NULL)
{
int i;
long sum = 0;
memcpy(&divisor[guess], &divisor[1], sizeof(numeric));
divisor[guess].buf = digitbuf_alloc(divisor[guess].ndigits);
if (divisor[guess].buf == NULL)
goto done;
divisor[guess].digits = divisor[guess].buf;
for (i = divisor[1].ndigits - 1; i >= 0; i--)
{
sum += divisor[1].digits[i] * guess;
divisor[guess].digits[i] = sum % 10;
sum /= 10;
}
}
divisor[guess].weight = weight_tmp;
divisor[guess].rscale = rscale_tmp;
stat = cmp_abs(÷nd, &divisor[guess]);
if (stat >= 0)
break;
guess--;
}
res_digits[ri + 1] = guess;
if (stat == 0)
{
ri++;
break;
}
weight_tmp--;
rscale_tmp++;
if (guess == 0)
continue;
if (sub_abs(÷nd, &divisor[guess], ÷nd) != 0)
goto done;
first_nextdigit = dividend.weight - weight_tmp;
first_have = 0;
if (first_nextdigit >= 0 && first_nextdigit < dividend.ndigits)
first_have = dividend.digits[first_nextdigit];
first_nextdigit++;
}
result->ndigits = ri + 1;
if (ri == res_ndigits + 1)
{
int carry = (res_digits[ri] > 4) ? 1 : 0;
result->ndigits = ri;
res_digits[ri] = 0;
while (carry && ri > 0)
{
carry += res_digits[--ri];
res_digits[ri] = carry % 10;
carry /= 10;
}
}
while (result->ndigits > 0 && *(result->digits) == 0)
{
(result->digits)++;
(result->weight)--;
(result->ndigits)--;
}
while (result->ndigits > 0 && result->digits[result->ndigits - 1] == 0)
(result->ndigits)--;
if (result->ndigits == 0)
result->sign = NUMERIC_POS;
result->dscale = res_dscale;
err = 0; /* if we've made it this far, return success */
done:
/*
* Tidy up
*/
if (dividend.buf != NULL)
digitbuf_free(dividend.buf);
for (i = 1; i < 10; i++)
{
if (divisor[i].buf != NULL)
digitbuf_free(divisor[i].buf);
}
return err;
}
int
PGTYPESnumeric_cmp(numeric *var1, numeric *var2)
{
/* use cmp_abs function to calculate the result */
/* both are positive: normal comparison with cmp_abs */
if (var1->sign == NUMERIC_POS && var2->sign == NUMERIC_POS)
return cmp_abs(var1, var2);
/* both are negative: return the inverse of the normal comparison */
if (var1->sign == NUMERIC_NEG && var2->sign == NUMERIC_NEG)
{
/*
* instead of inverting the result, we invert the parameter ordering
*/
return cmp_abs(var2, var1);
}
/* one is positive, one is negative: trivial */
if (var1->sign == NUMERIC_POS && var2->sign == NUMERIC_NEG)
return 1;
if (var1->sign == NUMERIC_NEG && var2->sign == NUMERIC_POS)
return -1;
errno = PGTYPES_NUM_BAD_NUMERIC;
return INT_MAX;
}
int
PGTYPESnumeric_from_int(signed int int_val, numeric *var)
{
/* implicit conversion */
signed long int long_int = int_val;
return PGTYPESnumeric_from_long(long_int, var);
}
int
PGTYPESnumeric_from_long(signed long int long_val, numeric *var)
{
/* calculate the size of the long int number */
/* a number n needs log_10 n digits */
/*
* however we multiply by 10 each time and compare instead of calculating
* the logarithm
*/
int size = 0;
int i;
signed long int abs_long_val = long_val;
signed long int extract;
signed long int reach_limit;
if (abs_long_val < 0)
{
abs_long_val *= -1;
var->sign = NUMERIC_NEG;
}
else
var->sign = NUMERIC_POS;
reach_limit = 1;
do
{
size++;
reach_limit *= 10;
} while (reach_limit - 1 < abs_long_val && reach_limit <= LONG_MAX / 10);
if (reach_limit > LONG_MAX / 10)
{
/* add the first digit and a .0 */
size += 2;
}
else
{
/* always add a .0 */
size++;
reach_limit /= 10;
}
if (alloc_var(var, size) < 0)
return -1;
var->rscale = 1;
var->dscale = 1;
var->weight = size - 2;
i = 0;
do
{
extract = abs_long_val - (abs_long_val % reach_limit);
var->digits[i] = extract / reach_limit;
abs_long_val -= extract;
i++;
reach_limit /= 10;
/*
* we can abandon if abs_long_val reaches 0, because the memory is
* initialized properly and filled with '0', so converting 10000 in
* only one step is no problem
*/
} while (abs_long_val > 0);
return 0;
}
int
PGTYPESnumeric_copy(numeric *src, numeric *dst)
{
int i;
if (dst == NULL)
return -1;
zero_var(dst);
dst->weight = src->weight;
dst->rscale = src->rscale;
dst->dscale = src->dscale;
dst->sign = src->sign;
if (alloc_var(dst, src->ndigits) != 0)
return -1;
for (i = 0; i < src->ndigits; i++)
dst->digits[i] = src->digits[i];
return 0;
}
int
PGTYPESnumeric_from_double(double d, numeric *dst)
{
char buffer[DBL_DIG + 100];
numeric *tmp;
int i;
if (sprintf(buffer, "%.*g", DBL_DIG, d) <= 0)
return -1;
if ((tmp = PGTYPESnumeric_from_asc(buffer, NULL)) == NULL)
return -1;
i = PGTYPESnumeric_copy(tmp, dst);
PGTYPESnumeric_free(tmp);
if (i != 0)
return -1;
errno = 0;
return 0;
}
static int
numericvar_to_double(numeric *var, double *dp)
{
char *tmp;
double val;
char *endptr;
numeric *varcopy = PGTYPESnumeric_new();
if (varcopy == NULL)
return -1;
if (PGTYPESnumeric_copy(var, varcopy) < 0)
{
PGTYPESnumeric_free(varcopy);
return -1;
}
tmp = get_str_from_var(varcopy, varcopy->dscale);
PGTYPESnumeric_free(varcopy);
if (tmp == NULL)
return -1;
/*
* strtod does not reset errno to 0 in case of success.
*/
errno = 0;
val = strtod(tmp, &endptr);
if (errno == ERANGE)
{
free(tmp);
if (val == 0)
errno = PGTYPES_NUM_UNDERFLOW;
else
errno = PGTYPES_NUM_OVERFLOW;
return -1;
}
/* can't free tmp yet, endptr points still into it */
if (*endptr != '\0')
{
/* shouldn't happen ... */
free(tmp);
errno = PGTYPES_NUM_BAD_NUMERIC;
return -1;
}
free(tmp);
*dp = val;
return 0;
}
int
PGTYPESnumeric_to_double(numeric *nv, double *dp)
{
double tmp;
if (numericvar_to_double(nv, &tmp) != 0)
return -1;
*dp = tmp;
return 0;
}
int
PGTYPESnumeric_to_int(numeric *nv, int *ip)
{
long l;
int i;
if ((i = PGTYPESnumeric_to_long(nv, &l)) != 0)
return i;
if (l < -INT_MAX || l > INT_MAX)
{
errno = PGTYPES_NUM_OVERFLOW;
return -1;
}
*ip = (int) l;
return 0;
}
int
PGTYPESnumeric_to_long(numeric *nv, long *lp)
{
char *s = PGTYPESnumeric_to_asc(nv, 0);
char *endptr;
if (s == NULL)
return -1;
errno = 0;
*lp = strtol(s, &endptr, 10);
if (endptr == s)
{
/* this should not happen actually */
free(s);
return -1;
}
free(s);
if (errno == ERANGE)
{
if (*lp == LONG_MIN)
errno = PGTYPES_NUM_UNDERFLOW;
else
errno = PGTYPES_NUM_OVERFLOW;
return -1;
}
return 0;
}
int
PGTYPESnumeric_to_decimal(numeric *src, decimal *dst)
{
int i;
if (src->ndigits > DECSIZE)
{
errno = PGTYPES_NUM_OVERFLOW;
return -1;
}
dst->weight = src->weight;
dst->rscale = src->rscale;
dst->dscale = src->dscale;
dst->sign = src->sign;
dst->ndigits = src->ndigits;
for (i = 0; i < src->ndigits; i++)
dst->digits[i] = src->digits[i];
return 0;
}
int
PGTYPESnumeric_from_decimal(decimal *src, numeric *dst)
{
int i;
zero_var(dst);
dst->weight = src->weight;
dst->rscale = src->rscale;
dst->dscale = src->dscale;
dst->sign = src->sign;
if (alloc_var(dst, src->ndigits) != 0)
return -1;
for (i = 0; i < src->ndigits; i++)
dst->digits[i] = src->digits[i];
return 0;
}
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