Upon further review, I've updated the patch. This avoids possible name
conflicts with other functions. See attached.
On Sat, Feb 8, 2025 at 3:24 PM Ed Behn <[email protected]> wrote:
> I've created a patch (attached) to implement the changes discussed below.
>
> This change moves the definition of the NumericVar structure to numeric.h.
> Function definitions for functions used to work with NumericVar are also
> moved to the header as are definitions of functions used to convert
> NumericVar to Numeric. (Numeric is used to store numeric and decimal types.)
>
> All of this is so that third-party libraries can access numeric and
> decimal values without having to access the opaque Numeric structure.
>
> There is actually no new code. Code is simply moved from numeric.c to
> numeric.h.
>
> This is a patch against branch master.
>
> This successfully compiles and is tested with regression tests.
>
> Also attached is a code sample that uses the change.
>
> Please provide feedback. I'm planning to submit this for the March
> commitfest.
>
> -Ed
>
> On Wed, Sep 18, 2024 at 9:50 AM Robert Haas <[email protected]> wrote:
>
>> On Sat, Sep 14, 2024 at 2:10 PM Ed Behn <[email protected]> wrote:
>> > Was there a resolution of this? I'm wondering if it is worth it for
>> me to submit a PR for the next commitfest.
>>
>> Well, it seems like what you want is different than what I want, and
>> what Tom wants is different from both of us. I'd like there to be a
>> way forward here but at the moment I'm not quite sure what it is.
>>
>> --
>> Robert Haas
>> EDB: http://www.enterprisedb.com
>>
>
diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c
index 40dcbc7b671..ec5e4b5ee32 100644
--- a/src/backend/utils/adt/numeric.c
+++ b/src/backend/utils/adt/numeric.c
@@ -45,65 +45,11 @@
/* ----------
* Uncomment the following to enable compilation of dump_numeric()
- * and dump_var() and to get a dump of any result produced by make_result().
+ * and dump_var() and to get a dump of any result produced by numeric_make_result().
* ----------
#define NUMERIC_DEBUG
*/
-
-/* ----------
- * Local data types
- *
- * Numeric values are represented in a base-NBASE floating point format.
- * Each "digit" ranges from 0 to NBASE-1. The type NumericDigit is signed
- * and wide enough to store a digit. We assume that NBASE*NBASE can fit in
- * an int. Although the purely calculational routines could handle any even
- * NBASE that's less than sqrt(INT_MAX), in practice we are only interested
- * in NBASE a power of ten, so that I/O conversions and decimal rounding
- * are easy. Also, it's actually more efficient if NBASE is rather less than
- * sqrt(INT_MAX), so that there is "headroom" for mul_var and div_var to
- * postpone processing carries.
- *
- * Values of NBASE other than 10000 are considered of historical interest only
- * and are no longer supported in any sense; no mechanism exists for the client
- * to discover the base, so every client supporting binary mode expects the
- * base-10000 format. If you plan to change this, also note the numeric
- * abbreviation code, which assumes NBASE=10000.
- * ----------
- */
-
-#if 0
-#define NBASE 10
-#define HALF_NBASE 5
-#define DEC_DIGITS 1 /* decimal digits per NBASE digit */
-#define MUL_GUARD_DIGITS 4 /* these are measured in NBASE digits */
-#define DIV_GUARD_DIGITS 8
-
-typedef signed char NumericDigit;
-#endif
-
-#if 0
-#define NBASE 100
-#define HALF_NBASE 50
-#define DEC_DIGITS 2 /* decimal digits per NBASE digit */
-#define MUL_GUARD_DIGITS 3 /* these are measured in NBASE digits */
-#define DIV_GUARD_DIGITS 6
-
-typedef signed char NumericDigit;
-#endif
-
-#if 1
-#define NBASE 10000
-#define HALF_NBASE 5000
-#define DEC_DIGITS 4 /* decimal digits per NBASE digit */
-#define MUL_GUARD_DIGITS 2 /* these are measured in NBASE digits */
-#define DIV_GUARD_DIGITS 4
-
-typedef int16 NumericDigit;
-#endif
-
-#define NBASE_SQR (NBASE * NBASE)
-
/*
* The Numeric type as stored on disk.
*
@@ -252,75 +198,6 @@ struct NumericData
| ((n)->choice.n_short.n_header & NUMERIC_SHORT_WEIGHT_MASK)) \
: ((n)->choice.n_long.n_weight))
-/*
- * Maximum weight of a stored Numeric value (based on the use of int16 for the
- * weight in NumericLong). Note that intermediate values held in NumericVar
- * and NumericSumAccum variables may have much larger weights.
- */
-#define NUMERIC_WEIGHT_MAX PG_INT16_MAX
-
-/* ----------
- * NumericVar is the format we use for arithmetic. The digit-array part
- * is the same as the NumericData storage format, but the header is more
- * complex.
- *
- * The value represented by a NumericVar is determined by the sign, weight,
- * ndigits, and digits[] array. If it is a "special" value (NaN or Inf)
- * then only the sign field matters; ndigits should be zero, and the weight
- * and dscale fields are ignored.
- *
- * Note: the first digit of a NumericVar's value is assumed to be multiplied
- * by NBASE ** weight. Another way to say it is that there are weight+1
- * digits before the decimal point. It is possible to have weight < 0.
- *
- * buf points at the physical start of the palloc'd digit buffer for the
- * NumericVar. digits points at the first digit in actual use (the one
- * with the specified weight). We normally leave an unused digit or two
- * (preset to zeroes) between buf and digits, so that there is room to store
- * a carry out of the top digit without reallocating space. We just need to
- * decrement digits (and increment weight) to make room for the carry digit.
- * (There is no such extra space in a numeric value stored in the database,
- * only in a NumericVar in memory.)
- *
- * If buf is NULL then the digit buffer isn't actually palloc'd and should
- * not be freed --- see the constants below for an example.
- *
- * dscale, or display scale, is the nominal precision expressed as number
- * of digits after the decimal point (it must always be >= 0 at present).
- * dscale may be more than the number of physically stored fractional digits,
- * implying that we have suppressed storage of significant trailing zeroes.
- * It should never be less than the number of stored digits, since that would
- * imply hiding digits that are present. NOTE that dscale is always expressed
- * in *decimal* digits, and so it may correspond to a fractional number of
- * base-NBASE digits --- divide by DEC_DIGITS to convert to NBASE digits.
- *
- * rscale, or result scale, is the target precision for a computation.
- * Like dscale it is expressed as number of *decimal* digits after the decimal
- * point, and is always >= 0 at present.
- * Note that rscale is not stored in variables --- it's figured on-the-fly
- * from the dscales of the inputs.
- *
- * While we consistently use "weight" to refer to the base-NBASE weight of
- * a numeric value, it is convenient in some scale-related calculations to
- * make use of the base-10 weight (ie, the approximate log10 of the value).
- * To avoid confusion, such a decimal-units weight is called a "dweight".
- *
- * NB: All the variable-level functions are written in a style that makes it
- * possible to give one and the same variable as argument and destination.
- * This is feasible because the digit buffer is separate from the variable.
- * ----------
- */
-typedef struct NumericVar
-{
- int ndigits; /* # of digits in digits[] - can be 0! */
- int weight; /* weight of first digit */
- int sign; /* NUMERIC_POS, _NEG, _NAN, _PINF, or _NINF */
- int dscale; /* display scale */
- NumericDigit *buf; /* start of palloc'd space for digits[] */
- NumericDigit *digits; /* base-NBASE digits */
-} NumericVar;
-
-
/* ----------
* Data for generate_series
* ----------
@@ -491,8 +368,6 @@ static void dump_var(const char *str, NumericVar *var);
pfree(buf); \
} while (0)
-#define init_var(v) memset(v, 0, sizeof(NumericVar))
-
#define NUMERIC_DIGITS(num) (NUMERIC_HEADER_IS_SHORT(num) ? \
(num)->choice.n_short.n_data : (num)->choice.n_long.n_data)
#define NUMERIC_NDIGITS(num) \
@@ -502,10 +377,6 @@ static void dump_var(const char *str, NumericVar *var);
(weight) <= NUMERIC_SHORT_WEIGHT_MAX && \
(weight) >= NUMERIC_SHORT_WEIGHT_MIN)
-static void alloc_var(NumericVar *var, int ndigits);
-static void free_var(NumericVar *var);
-static void zero_var(NumericVar *var);
-
static bool set_var_from_str(const char *str, const char *cp,
NumericVar *dest, const char **endptr,
Node *escontext);
@@ -514,9 +385,6 @@ static bool set_var_from_non_decimal_integer_str(const char *str,
int base, NumericVar *dest,
const char **endptr,
Node *escontext);
-static void set_var_from_num(Numeric num, NumericVar *dest);
-static void init_var_from_num(Numeric num, NumericVar *dest);
-static void set_var_from_var(const NumericVar *value, NumericVar *dest);
static char *get_str_from_var(const NumericVar *var);
static char *get_str_from_var_sci(const NumericVar *var, int rscale);
@@ -524,8 +392,6 @@ static void numericvar_serialize(StringInfo buf, const NumericVar *var);
static void numericvar_deserialize(StringInfo buf, NumericVar *var);
static Numeric duplicate_numeric(Numeric num);
-static Numeric make_result(const NumericVar *var);
-static Numeric make_result_opt_error(const NumericVar *var, bool *have_error);
static bool apply_typmod(NumericVar *var, int32 typmod, Node *escontext);
static bool apply_typmod_special(Numeric num, int32 typmod, Node *escontext);
@@ -687,17 +553,17 @@ numeric_in(PG_FUNCTION_ARGS)
*/
if (pg_strncasecmp(numstart, "NaN", 3) == 0)
{
- res = make_result(&const_nan);
+ res = numeric_make_result(&const_nan);
cp = numstart + 3;
}
else if (pg_strncasecmp(cp, "Infinity", 8) == 0)
{
- res = make_result(sign == NUMERIC_POS ? &const_pinf : &const_ninf);
+ res = numeric_make_result(sign == NUMERIC_POS ? &const_pinf : &const_ninf);
cp += 8;
}
else if (pg_strncasecmp(cp, "inf", 3) == 0)
{
- res = make_result(sign == NUMERIC_POS ? &const_pinf : &const_ninf);
+ res = numeric_make_result(sign == NUMERIC_POS ? &const_pinf : &const_ninf);
cp += 3;
}
else
@@ -787,7 +653,7 @@ numeric_in(PG_FUNCTION_ARGS)
if (!apply_typmod(&value, typmod, escontext))
PG_RETURN_NULL();
- res = make_result_opt_error(&value, &have_error);
+ res = numeric_make_result_opt_error(&value, &have_error);
if (have_error)
ereturn(escontext, (Datum) 0,
@@ -1130,7 +996,7 @@ numeric_recv(PG_FUNCTION_ARGS)
* extra code (about as much as trunc_var involves), and it might cause
* client compatibility issues. Be careful not to apply trunc_var to
* special values, as it could do the wrong thing; we don't need it
- * anyway, since make_result will ignore all but the sign field.
+ * anyway, since make_result_numericvar will ignore all but the sign field.
*
* After doing that, be sure to check the typmod restriction.
*/
@@ -1141,12 +1007,12 @@ numeric_recv(PG_FUNCTION_ARGS)
(void) apply_typmod(&value, typmod, NULL);
- res = make_result(&value);
+ res = numeric_make_result(&value);
}
else
{
/* apply_typmod_special wants us to make the Numeric first */
- res = make_result(&value);
+ res = numeric_make_result(&value);
(void) apply_typmod_special(res, typmod, NULL);
}
@@ -1313,7 +1179,7 @@ numeric (PG_FUNCTION_ARGS)
set_var_from_num(num, &var);
(void) apply_typmod(&var, typmod, NULL);
- new = make_result(&var);
+ new = numeric_make_result(&var);
free_var(&var);
@@ -1515,16 +1381,16 @@ numeric_sign(PG_FUNCTION_ARGS)
* Handle NaN (infinities can be handled normally)
*/
if (NUMERIC_IS_NAN(num))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
switch (numeric_sign_internal(num))
{
case 0:
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
case 1:
- PG_RETURN_NUMERIC(make_result(&const_one));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_one));
case -1:
- PG_RETURN_NUMERIC(make_result(&const_minus_one));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_minus_one));
}
Assert(false);
@@ -1579,7 +1445,7 @@ numeric_round(PG_FUNCTION_ARGS)
/*
* Return the rounded result
*/
- res = make_result(&arg);
+ res = numeric_make_result(&arg);
free_var(&arg);
PG_RETURN_NUMERIC(res);
@@ -1631,7 +1497,7 @@ numeric_trunc(PG_FUNCTION_ARGS)
/*
* Return the truncated result
*/
- res = make_result(&arg);
+ res = numeric_make_result(&arg);
free_var(&arg);
PG_RETURN_NUMERIC(res);
@@ -1659,7 +1525,7 @@ numeric_ceil(PG_FUNCTION_ARGS)
init_var_from_num(num, &result);
ceil_var(&result, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
PG_RETURN_NUMERIC(res);
@@ -1687,7 +1553,7 @@ numeric_floor(PG_FUNCTION_ARGS)
init_var_from_num(num, &result);
floor_var(&result, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
PG_RETURN_NUMERIC(res);
@@ -1811,7 +1677,7 @@ generate_series_step_numeric(PG_FUNCTION_ARGS)
(fctx->step.sign == NUMERIC_NEG &&
cmp_var(&fctx->current, &fctx->stop) >= 0))
{
- Numeric result = make_result(&fctx->current);
+ Numeric result = numeric_make_result(&fctx->current);
/* switch to memory context appropriate for iteration calculation */
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
@@ -2995,26 +2861,26 @@ numeric_add_opt_error(Numeric num1, Numeric num2, bool *have_error)
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
{
if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
- return make_result(&const_nan);
+ return numeric_make_result(&const_nan);
if (NUMERIC_IS_PINF(num1))
{
if (NUMERIC_IS_NINF(num2))
- return make_result(&const_nan); /* Inf + -Inf */
+ return numeric_make_result(&const_nan); /* Inf + -Inf */
else
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
}
if (NUMERIC_IS_NINF(num1))
{
if (NUMERIC_IS_PINF(num2))
- return make_result(&const_nan); /* -Inf + Inf */
+ return numeric_make_result(&const_nan); /* -Inf + Inf */
else
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
}
/* by here, num1 must be finite, so num2 is not */
if (NUMERIC_IS_PINF(num2))
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
Assert(NUMERIC_IS_NINF(num2));
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
}
/*
@@ -3026,7 +2892,7 @@ numeric_add_opt_error(Numeric num1, Numeric num2, bool *have_error)
init_var(&result);
add_var(&arg1, &arg2, &result);
- res = make_result_opt_error(&result, have_error);
+ res = numeric_make_result_opt_error(&result, have_error);
free_var(&result);
@@ -3073,26 +2939,26 @@ numeric_sub_opt_error(Numeric num1, Numeric num2, bool *have_error)
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
{
if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
- return make_result(&const_nan);
+ return numeric_make_result(&const_nan);
if (NUMERIC_IS_PINF(num1))
{
if (NUMERIC_IS_PINF(num2))
- return make_result(&const_nan); /* Inf - Inf */
+ return numeric_make_result(&const_nan); /* Inf - Inf */
else
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
}
if (NUMERIC_IS_NINF(num1))
{
if (NUMERIC_IS_NINF(num2))
- return make_result(&const_nan); /* -Inf - -Inf */
+ return numeric_make_result(&const_nan); /* -Inf - -Inf */
else
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
}
/* by here, num1 must be finite, so num2 is not */
if (NUMERIC_IS_PINF(num2))
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
Assert(NUMERIC_IS_NINF(num2));
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
}
/*
@@ -3104,7 +2970,7 @@ numeric_sub_opt_error(Numeric num1, Numeric num2, bool *have_error)
init_var(&result);
sub_var(&arg1, &arg2, &result);
- res = make_result_opt_error(&result, have_error);
+ res = numeric_make_result_opt_error(&result, have_error);
free_var(&result);
@@ -3151,17 +3017,17 @@ numeric_mul_opt_error(Numeric num1, Numeric num2, bool *have_error)
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
{
if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
- return make_result(&const_nan);
+ return numeric_make_result(&const_nan);
if (NUMERIC_IS_PINF(num1))
{
switch (numeric_sign_internal(num2))
{
case 0:
- return make_result(&const_nan); /* Inf * 0 */
+ return numeric_make_result(&const_nan); /* Inf * 0 */
case 1:
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
case -1:
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
}
Assert(false);
}
@@ -3170,11 +3036,11 @@ numeric_mul_opt_error(Numeric num1, Numeric num2, bool *have_error)
switch (numeric_sign_internal(num2))
{
case 0:
- return make_result(&const_nan); /* -Inf * 0 */
+ return numeric_make_result(&const_nan); /* -Inf * 0 */
case 1:
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
case -1:
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
}
Assert(false);
}
@@ -3184,11 +3050,11 @@ numeric_mul_opt_error(Numeric num1, Numeric num2, bool *have_error)
switch (numeric_sign_internal(num1))
{
case 0:
- return make_result(&const_nan); /* 0 * Inf */
+ return numeric_make_result(&const_nan); /* 0 * Inf */
case 1:
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
case -1:
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
}
Assert(false);
}
@@ -3196,11 +3062,11 @@ numeric_mul_opt_error(Numeric num1, Numeric num2, bool *have_error)
switch (numeric_sign_internal(num1))
{
case 0:
- return make_result(&const_nan); /* 0 * -Inf */
+ return numeric_make_result(&const_nan); /* 0 * -Inf */
case 1:
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
case -1:
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
}
Assert(false);
}
@@ -3225,7 +3091,7 @@ numeric_mul_opt_error(Numeric num1, Numeric num2, bool *have_error)
if (result.dscale > NUMERIC_DSCALE_MAX)
round_var(&result, NUMERIC_DSCALE_MAX);
- res = make_result_opt_error(&result, have_error);
+ res = numeric_make_result_opt_error(&result, have_error);
free_var(&result);
@@ -3276,11 +3142,11 @@ numeric_div_opt_error(Numeric num1, Numeric num2, bool *have_error)
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
{
if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
- return make_result(&const_nan);
+ return numeric_make_result(&const_nan);
if (NUMERIC_IS_PINF(num1))
{
if (NUMERIC_IS_SPECIAL(num2))
- return make_result(&const_nan); /* Inf / [-]Inf */
+ return numeric_make_result(&const_nan); /* Inf / [-]Inf */
switch (numeric_sign_internal(num2))
{
case 0:
@@ -3294,16 +3160,16 @@ numeric_div_opt_error(Numeric num1, Numeric num2, bool *have_error)
errmsg("division by zero")));
break;
case 1:
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
case -1:
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
}
Assert(false);
}
if (NUMERIC_IS_NINF(num1))
{
if (NUMERIC_IS_SPECIAL(num2))
- return make_result(&const_nan); /* -Inf / [-]Inf */
+ return numeric_make_result(&const_nan); /* -Inf / [-]Inf */
switch (numeric_sign_internal(num2))
{
case 0:
@@ -3317,9 +3183,9 @@ numeric_div_opt_error(Numeric num1, Numeric num2, bool *have_error)
errmsg("division by zero")));
break;
case 1:
- return make_result(&const_ninf);
+ return numeric_make_result(&const_ninf);
case -1:
- return make_result(&const_pinf);
+ return numeric_make_result(&const_pinf);
}
Assert(false);
}
@@ -3330,7 +3196,7 @@ numeric_div_opt_error(Numeric num1, Numeric num2, bool *have_error)
* otherwise throw an underflow error. But the numeric type doesn't
* really do underflow, so let's just return zero.
*/
- return make_result(&const_zero);
+ return numeric_make_result(&const_zero);
}
/*
@@ -3360,7 +3226,7 @@ numeric_div_opt_error(Numeric num1, Numeric num2, bool *have_error)
*/
div_var(&arg1, &arg2, &result, rscale, true, true);
- res = make_result_opt_error(&result, have_error);
+ res = numeric_make_result_opt_error(&result, have_error);
free_var(&result);
@@ -3389,11 +3255,11 @@ numeric_div_trunc(PG_FUNCTION_ARGS)
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
{
if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
if (NUMERIC_IS_PINF(num1))
{
if (NUMERIC_IS_SPECIAL(num2))
- PG_RETURN_NUMERIC(make_result(&const_nan)); /* Inf / [-]Inf */
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan)); /* Inf / [-]Inf */
switch (numeric_sign_internal(num2))
{
case 0:
@@ -3402,16 +3268,16 @@ numeric_div_trunc(PG_FUNCTION_ARGS)
errmsg("division by zero")));
break;
case 1:
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
case -1:
- PG_RETURN_NUMERIC(make_result(&const_ninf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_ninf));
}
Assert(false);
}
if (NUMERIC_IS_NINF(num1))
{
if (NUMERIC_IS_SPECIAL(num2))
- PG_RETURN_NUMERIC(make_result(&const_nan)); /* -Inf / [-]Inf */
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan)); /* -Inf / [-]Inf */
switch (numeric_sign_internal(num2))
{
case 0:
@@ -3420,9 +3286,9 @@ numeric_div_trunc(PG_FUNCTION_ARGS)
errmsg("division by zero")));
break;
case 1:
- PG_RETURN_NUMERIC(make_result(&const_ninf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_ninf));
case -1:
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
}
Assert(false);
}
@@ -3433,7 +3299,7 @@ numeric_div_trunc(PG_FUNCTION_ARGS)
* otherwise throw an underflow error. But the numeric type doesn't
* really do underflow, so let's just return zero.
*/
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
}
/*
@@ -3449,7 +3315,7 @@ numeric_div_trunc(PG_FUNCTION_ARGS)
*/
div_var(&arg1, &arg2, &result, 0, false, true);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -3501,7 +3367,7 @@ numeric_mod_opt_error(Numeric num1, Numeric num2, bool *have_error)
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
{
if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
- return make_result(&const_nan);
+ return numeric_make_result(&const_nan);
if (NUMERIC_IS_INF(num1))
{
if (numeric_sign_internal(num2) == 0)
@@ -3516,7 +3382,7 @@ numeric_mod_opt_error(Numeric num1, Numeric num2, bool *have_error)
errmsg("division by zero")));
}
/* Inf % any nonzero = NaN */
- return make_result(&const_nan);
+ return numeric_make_result(&const_nan);
}
/* num2 must be [-]Inf; result is num1 regardless of sign of num2 */
return duplicate_numeric(num1);
@@ -3538,7 +3404,7 @@ numeric_mod_opt_error(Numeric num1, Numeric num2, bool *have_error)
mod_var(&arg1, &arg2, &result);
- res = make_result_opt_error(&result, NULL);
+ res = numeric_make_result_opt_error(&result, NULL);
free_var(&result);
@@ -3571,7 +3437,7 @@ numeric_inc(PG_FUNCTION_ARGS)
add_var(&arg, &const_one, &arg);
- res = make_result(&arg);
+ res = numeric_make_result(&arg);
free_var(&arg);
@@ -3650,7 +3516,7 @@ numeric_gcd(PG_FUNCTION_ARGS)
* cases.
*/
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
/*
* Unpack the arguments
@@ -3665,7 +3531,7 @@ numeric_gcd(PG_FUNCTION_ARGS)
*/
gcd_var(&arg1, &arg2, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -3693,7 +3559,7 @@ numeric_lcm(PG_FUNCTION_ARGS)
* cases.
*/
if (NUMERIC_IS_SPECIAL(num1) || NUMERIC_IS_SPECIAL(num2))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
/*
* Unpack the arguments
@@ -3725,7 +3591,7 @@ numeric_lcm(PG_FUNCTION_ARGS)
result.dscale = Max(arg1.dscale, arg2.dscale);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -3752,7 +3618,7 @@ numeric_fac(PG_FUNCTION_ARGS)
errmsg("factorial of a negative number is undefined")));
if (num <= 1)
{
- res = make_result(&const_one);
+ res = numeric_make_result(&const_one);
PG_RETURN_NUMERIC(res);
}
/* Fail immediately if the result would overflow */
@@ -3776,7 +3642,7 @@ numeric_fac(PG_FUNCTION_ARGS)
mul_var(&result, &fact, &result, 0);
}
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&fact);
free_var(&result);
@@ -3849,7 +3715,7 @@ numeric_sqrt(PG_FUNCTION_ARGS)
*/
sqrt_var(&arg, &result, rscale);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -3879,7 +3745,7 @@ numeric_exp(PG_FUNCTION_ARGS)
{
/* Per POSIX, exp(-Inf) is zero */
if (NUMERIC_IS_NINF(num))
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
/* For NAN or PINF, just duplicate the input */
PG_RETURN_NUMERIC(duplicate_numeric(num));
}
@@ -3916,7 +3782,7 @@ numeric_exp(PG_FUNCTION_ARGS)
*/
exp_var(&arg, &result, rscale);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -3965,7 +3831,7 @@ numeric_ln(PG_FUNCTION_ARGS)
ln_var(&arg, &result, rscale);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -3997,7 +3863,7 @@ numeric_log(PG_FUNCTION_ARGS)
sign2;
if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
/* fail on negative inputs including -Inf, as log_var would */
sign1 = numeric_sign_internal(num1);
sign2 = numeric_sign_internal(num2);
@@ -4014,13 +3880,13 @@ numeric_log(PG_FUNCTION_ARGS)
{
/* log(Inf, Inf) reduces to Inf/Inf, so it's NaN */
if (NUMERIC_IS_PINF(num2))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
/* log(Inf, finite-positive) is zero (we don't throw underflow) */
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
}
Assert(NUMERIC_IS_PINF(num2));
/* log(finite-positive, Inf) is Inf */
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
}
/*
@@ -4036,7 +3902,7 @@ numeric_log(PG_FUNCTION_ARGS)
*/
log_var(&arg1, &arg2, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -4077,9 +3943,9 @@ numeric_power(PG_FUNCTION_ARGS)
{
init_var_from_num(num2, &arg2);
if (cmp_var(&arg2, &const_zero) == 0)
- PG_RETURN_NUMERIC(make_result(&const_one));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_one));
}
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
}
if (NUMERIC_IS_NAN(num2))
{
@@ -4087,9 +3953,9 @@ numeric_power(PG_FUNCTION_ARGS)
{
init_var_from_num(num1, &arg1);
if (cmp_var(&arg1, &const_one) == 0)
- PG_RETURN_NUMERIC(make_result(&const_one));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_one));
}
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
}
/* At least one input is infinite, but error rules still apply */
sign1 = numeric_sign_internal(num1);
@@ -4112,14 +3978,14 @@ numeric_power(PG_FUNCTION_ARGS)
{
init_var_from_num(num1, &arg1);
if (cmp_var(&arg1, &const_one) == 0)
- PG_RETURN_NUMERIC(make_result(&const_one));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_one));
}
/*
* For any value of x, if y is [-]0, 1.0 shall be returned.
*/
if (sign2 == 0)
- PG_RETURN_NUMERIC(make_result(&const_one));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_one));
/*
* For any odd integer value of y > 0, if x is [-]0, [-]0 shall be
@@ -4128,7 +3994,7 @@ numeric_power(PG_FUNCTION_ARGS)
* distinguish these two cases.)
*/
if (sign1 == 0 && sign2 > 0)
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
/*
* If x is -1, and y is [-]Inf, 1.0 shall be returned.
@@ -4151,14 +4017,14 @@ numeric_power(PG_FUNCTION_ARGS)
{
init_var_from_num(num1, &arg1);
if (cmp_var(&arg1, &const_minus_one) == 0)
- PG_RETURN_NUMERIC(make_result(&const_one));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_one));
arg1.sign = NUMERIC_POS; /* now arg1 = abs(x) */
abs_x_gt_one = (cmp_var(&arg1, &const_one) > 0);
}
if (abs_x_gt_one == (sign2 > 0))
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
else
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
}
/*
@@ -4169,9 +4035,9 @@ numeric_power(PG_FUNCTION_ARGS)
if (NUMERIC_IS_PINF(num1))
{
if (sign2 > 0)
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
else
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
}
Assert(NUMERIC_IS_NINF(num1));
@@ -4182,7 +4048,7 @@ numeric_power(PG_FUNCTION_ARGS)
* (Again, we need not distinguish these two cases.)
*/
if (sign2 < 0)
- PG_RETURN_NUMERIC(make_result(&const_zero));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_zero));
/*
* For y an odd integer > 0, if x is -Inf, -Inf shall be returned. For
@@ -4191,9 +4057,9 @@ numeric_power(PG_FUNCTION_ARGS)
init_var_from_num(num2, &arg2);
if (arg2.ndigits > 0 && arg2.ndigits == arg2.weight + 1 &&
(arg2.digits[arg2.ndigits - 1] & 1))
- PG_RETURN_NUMERIC(make_result(&const_ninf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_ninf));
else
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
}
/*
@@ -4224,7 +4090,7 @@ numeric_power(PG_FUNCTION_ARGS)
*/
power_var(&arg1, &arg2, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -4333,7 +4199,7 @@ numeric_trim_scale(PG_FUNCTION_ARGS)
init_var_from_num(num, &result);
result.dscale = get_min_scale(&result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
PG_RETURN_NUMERIC(res);
@@ -4382,7 +4248,7 @@ random_numeric(pg_prng_state *state, Numeric rmin, Numeric rmax)
random_var(state, &rmin_var, &rmax_var, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -4407,7 +4273,7 @@ int64_to_numeric(int64 val)
int64_to_numericvar(val, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -4496,7 +4362,7 @@ int64_div_fast_to_numeric(int64 val1, int log10val2)
result.weight -= w;
result.dscale = rscale;
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -4717,14 +4583,14 @@ float8_numeric(PG_FUNCTION_ARGS)
const char *endptr;
if (isnan(val))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
if (isinf(val))
{
if (val < 0)
- PG_RETURN_NUMERIC(make_result(&const_ninf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_ninf));
else
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
}
snprintf(buf, sizeof(buf), "%.*g", DBL_DIG, val);
@@ -4734,7 +4600,7 @@ float8_numeric(PG_FUNCTION_ARGS)
/* Assume we need not worry about leading/trailing spaces */
(void) set_var_from_str(buf, buf, &result, &endptr, NULL);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -4811,14 +4677,14 @@ float4_numeric(PG_FUNCTION_ARGS)
const char *endptr;
if (isnan(val))
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
if (isinf(val))
{
if (val < 0)
- PG_RETURN_NUMERIC(make_result(&const_ninf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_ninf));
else
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
}
snprintf(buf, sizeof(buf), "%.*g", FLT_DIG, val);
@@ -4828,7 +4694,7 @@ float4_numeric(PG_FUNCTION_ARGS)
/* Assume we need not worry about leading/trailing spaces */
(void) set_var_from_str(buf, buf, &result, &endptr, NULL);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -6202,7 +6068,7 @@ numeric_poly_sum(PG_FUNCTION_ARGS)
int128_to_numericvar(state->sumX, &result);
- res = make_result(&result);
+ res = numeric_make_result(&result);
free_var(&result);
@@ -6232,7 +6098,7 @@ numeric_poly_avg(PG_FUNCTION_ARGS)
int128_to_numericvar(state->sumX, &result);
countd = NumericGetDatum(int64_to_numeric(state->N));
- sumd = NumericGetDatum(make_result(&result));
+ sumd = NumericGetDatum(numeric_make_result(&result));
free_var(&result);
@@ -6257,21 +6123,21 @@ numeric_avg(PG_FUNCTION_ARGS)
PG_RETURN_NULL();
if (state->NaNcount > 0) /* there was at least one NaN input */
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
/* adding plus and minus infinities gives NaN */
if (state->pInfcount > 0 && state->nInfcount > 0)
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
if (state->pInfcount > 0)
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
if (state->nInfcount > 0)
- PG_RETURN_NUMERIC(make_result(&const_ninf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_ninf));
N_datum = NumericGetDatum(int64_to_numeric(state->N));
init_var(&sumX_var);
accum_sum_final(&state->sumX, &sumX_var);
- sumX_datum = NumericGetDatum(make_result(&sumX_var));
+ sumX_datum = NumericGetDatum(numeric_make_result(&sumX_var));
free_var(&sumX_var);
PG_RETURN_DATUM(DirectFunctionCall2(numeric_div, sumX_datum, N_datum));
@@ -6291,19 +6157,19 @@ numeric_sum(PG_FUNCTION_ARGS)
PG_RETURN_NULL();
if (state->NaNcount > 0) /* there was at least one NaN input */
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
/* adding plus and minus infinities gives NaN */
if (state->pInfcount > 0 && state->nInfcount > 0)
- PG_RETURN_NUMERIC(make_result(&const_nan));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_nan));
if (state->pInfcount > 0)
- PG_RETURN_NUMERIC(make_result(&const_pinf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_pinf));
if (state->nInfcount > 0)
- PG_RETURN_NUMERIC(make_result(&const_ninf));
+ PG_RETURN_NUMERIC(numeric_make_result(&const_ninf));
init_var(&sumX_var);
accum_sum_final(&state->sumX, &sumX_var);
- result = make_result(&sumX_var);
+ result = numeric_make_result(&sumX_var);
free_var(&sumX_var);
PG_RETURN_NUMERIC(result);
@@ -6357,7 +6223,7 @@ numeric_stddev_internal(NumericAggState *state,
* float8 functions, any infinity input produces NaN output.
*/
if (state->NaNcount > 0 || state->pInfcount > 0 || state->nInfcount > 0)
- return make_result(&const_nan);
+ return numeric_make_result(&const_nan);
/* OK, normal calculation applies */
init_var(&vN);
@@ -6381,7 +6247,7 @@ numeric_stddev_internal(NumericAggState *state,
if (cmp_var(&vsumX2, &const_zero) <= 0)
{
/* Watch out for roundoff error producing a negative numerator */
- res = make_result(&const_zero);
+ res = numeric_make_result(&const_zero);
}
else
{
@@ -6394,7 +6260,7 @@ numeric_stddev_internal(NumericAggState *state,
if (!variance)
sqrt_var(&vsumX, &vsumX, rscale); /* stddev */
- res = make_result(&vsumX);
+ res = numeric_make_result(&vsumX);
}
free_var(&vNminus1);
@@ -7067,7 +6933,7 @@ dump_var(const char *str, NumericVar *var)
*
* Allocate a digit buffer of ndigits digits (plus a spare digit for rounding)
*/
-static void
+void
alloc_var(NumericVar *var, int ndigits)
{
digitbuf_free(var->buf);
@@ -7083,7 +6949,7 @@ alloc_var(NumericVar *var, int ndigits)
*
* Return the digit buffer of a variable to the free pool
*/
-static void
+void
free_var(NumericVar *var)
{
digitbuf_free(var->buf);
@@ -7099,7 +6965,7 @@ free_var(NumericVar *var)
* Set a variable to ZERO.
* Note: its dscale is not touched.
*/
-static void
+void
zero_var(NumericVar *var)
{
digitbuf_free(var->buf);
@@ -7221,8 +7087,8 @@ set_var_from_str(const char *str, const char *cp,
* INT_MAX/2 due to the MaxAllocSize limit on string length, so
* constraining the exponent similarly should be enough to prevent
* integer overflow in this function. If the value is too large to
- * fit in storage format, make_result() will complain about it later;
- * for consistency use the same ereport errcode/text as make_result().
+ * fit in storage format, numeric_make_result() will complain about it later;
+ * for consistency use the same ereport errcode/text as numeric_make_result().
*/
/* exponent sign */
@@ -7534,7 +7400,7 @@ invalid_syntax:
*
* Convert the packed db format into a variable
*/
-static void
+void
set_var_from_num(Numeric num, NumericVar *dest)
{
int ndigits;
@@ -7565,7 +7431,7 @@ set_var_from_num(Numeric num, NumericVar *dest)
* propagate to the original Numeric! It's OK to use it as the destination
* argument of one of the calculational functions, though.
*/
-static void
+void
init_var_from_num(Numeric num, NumericVar *dest)
{
dest->ndigits = NUMERIC_NDIGITS(num);
@@ -7582,7 +7448,7 @@ init_var_from_num(Numeric num, NumericVar *dest)
*
* Copy one variable into another
*/
-static void
+void
set_var_from_var(const NumericVar *value, NumericVar *dest)
{
NumericDigit *newbuf;
@@ -7888,7 +7754,7 @@ duplicate_numeric(Numeric num)
}
/*
- * make_result_opt_error() -
+ * numeric_make_result_opt_error() -
*
* Create the packed db numeric format in palloc()'d memory from
* a variable. This will handle NaN and Infinity cases.
@@ -7896,8 +7762,8 @@ duplicate_numeric(Numeric num)
* If "have_error" isn't NULL, on overflow *have_error is set to true and
* NULL is returned. This is helpful when caller needs to handle errors.
*/
-static Numeric
-make_result_opt_error(const NumericVar *var, bool *have_error)
+Numeric
+numeric_make_result_opt_error(const NumericVar *var, bool *have_error)
{
Numeric result;
NumericDigit *digits = var->digits;
@@ -7927,7 +7793,7 @@ make_result_opt_error(const NumericVar *var, bool *have_error)
result->choice.n_header = sign;
/* the header word is all we need */
- dump_numeric("make_result()", result);
+ dump_numeric("numeric_make_result()", result);
return result;
}
@@ -7995,20 +7861,20 @@ make_result_opt_error(const NumericVar *var, bool *have_error)
}
}
- dump_numeric("make_result()", result);
+ dump_numeric("numeric_make_result()", result);
return result;
}
/*
- * make_result() -
+ * numeric_make_result() -
*
- * An interface to make_result_opt_error() without "have_error" argument.
+ * An interface to numeric_make_result_opt_error() without "have_error" argument.
*/
-static Numeric
-make_result(const NumericVar *var)
+Numeric
+numeric_make_result(const NumericVar *var)
{
- return make_result_opt_error(var, NULL);
+ return numeric_make_result_opt_error(var, NULL);
}
diff --git a/src/include/utils/numeric.h b/src/include/utils/numeric.h
index 9e79fc376cb..4a290577abd 100644
--- a/src/include/utils/numeric.h
+++ b/src/include/utils/numeric.h
@@ -42,6 +42,59 @@
#define NUMERIC_MAX_RESULT_SCALE (NUMERIC_MAX_PRECISION * 2)
+/* ----------
+ * Local data types
+ *
+ * Numeric values are represented in a base-NBASE floating point format.
+ * Each "digit" ranges from 0 to NBASE-1. The type NumericDigit is signed
+ * and wide enough to store a digit. We assume that NBASE*NBASE can fit in
+ * an int. Although the purely calculational routines could handle any even
+ * NBASE that's less than sqrt(INT_MAX), in practice we are only interested
+ * in NBASE a power of ten, so that I/O conversions and decimal rounding
+ * are easy. Also, it's actually more efficient if NBASE is rather less than
+ * sqrt(INT_MAX), so that there is "headroom" for mul_var and div_var to
+ * postpone processing carries.
+ *
+ * Values of NBASE other than 10000 are considered of historical interest only
+ * and are no longer supported in any sense; no mechanism exists for the client
+ * to discover the base, so every client supporting binary mode expects the
+ * base-10000 format. If you plan to change this, also note the numeric
+ * abbreviation code, which assumes NBASE=10000.
+ * ----------
+ */
+
+#if 0
+#define NBASE 10
+#define HALF_NBASE 5
+#define DEC_DIGITS 1 /* decimal digits per NBASE digit */
+#define MUL_GUARD_DIGITS 4 /* these are measured in NBASE digits */
+#define DIV_GUARD_DIGITS 8
+
+typedef signed char NumericDigit;
+#endif
+
+#if 0
+#define NBASE 100
+#define HALF_NBASE 50
+#define DEC_DIGITS 2 /* decimal digits per NBASE digit */
+#define MUL_GUARD_DIGITS 3 /* these are measured in NBASE digits */
+#define DIV_GUARD_DIGITS 6
+
+typedef signed char NumericDigit;
+#endif
+
+#if 1
+#define NBASE 10000
+#define HALF_NBASE 5000
+#define DEC_DIGITS 4 /* decimal digits per NBASE digit */
+#define MUL_GUARD_DIGITS 2 /* these are measured in NBASE digits */
+#define DIV_GUARD_DIGITS 4
+
+typedef int16 NumericDigit;
+#endif
+
+#define NBASE_SQR (NBASE * NBASE)
+
/*
* For inherently inexact calculations such as division and square root,
* we try to get at least this many significant digits; the idea is to
@@ -49,6 +102,84 @@
*/
#define NUMERIC_MIN_SIG_DIGITS 16
+/*
+ * sign field of NumericVar
+ */
+
+#define NUMERIC_POS 0x0000
+#define NUMERIC_NEG 0x4000
+#define NUMERIC_NAN 0xC000
+#define NUMERIC_PINF 0xD000
+#define NUMERIC_NINF 0xF000
+
+/*
+ * Maximum weight of a stored Numeric value (based on the use of int16 for the
+ * weight in NumericLong). Note that intermediate values held in NumericVar
+ * and NumericSumAccum variables may have much larger weights.
+ */
+ #define NUMERIC_WEIGHT_MAX PG_INT16_MAX
+
+/* ----------
+ * NumericVar is the format we use for arithmetic. The digit-array part
+ * is the same as the NumericData storage format, but the header is more
+ * complex.
+ *
+ * The value represented by a NumericVar is determined by the sign, weight,
+ * ndigits, and digits[] array. If it is a "special" value (NaN or Inf)
+ * then only the sign field matters; ndigits should be zero, and the weight
+ * and dscale fields are ignored.
+ *
+ * Note: the first digit of a NumericVar's value is assumed to be multiplied
+ * by NBASE ** weight. Another way to say it is that there are weight+1
+ * digits before the decimal point. It is possible to have weight < 0.
+ *
+ * buf points at the physical start of the palloc'd digit buffer for the
+ * NumericVar. digits points at the first digit in actual use (the one
+ * with the specified weight). We normally leave an unused digit or two
+ * (preset to zeroes) between buf and digits, so that there is room to store
+ * a carry out of the top digit without reallocating space. We just need to
+ * decrement digits (and increment weight) to make room for the carry digit.
+ * (There is no such extra space in a numeric value stored in the database,
+ * only in a NumericVar in memory.)
+ *
+ * If buf is NULL then the digit buffer isn't actually palloc'd and should
+ * not be freed --- see the constants below for an example.
+ *
+ * dscale, or display scale, is the nominal precision expressed as number
+ * of digits after the decimal point (it must always be >= 0 at present).
+ * dscale may be more than the number of physically stored fractional digits,
+ * implying that we have suppressed storage of significant trailing zeroes.
+ * It should never be less than the number of stored digits, since that would
+ * imply hiding digits that are present. NOTE that dscale is always expressed
+ * in *decimal* digits, and so it may correspond to a fractional number of
+ * base-NBASE digits --- divide by DEC_DIGITS to convert to NBASE digits.
+ *
+ * rscale, or result scale, is the target precision for a computation.
+ * Like dscale it is expressed as number of *decimal* digits after the decimal
+ * point, and is always >= 0 at present.
+ * Note that rscale is not stored in variables --- it's figured on-the-fly
+ * from the dscales of the inputs.
+ *
+ * While we consistently use "weight" to refer to the base-NBASE weight of
+ * a numeric value, it is convenient in some scale-related calculations to
+ * make use of the base-10 weight (ie, the approximate log10 of the value).
+ * To avoid confusion, such a decimal-units weight is called a "dweight".
+ *
+ * NB: All the variable-level functions are written in a style that makes it
+ * possible to give one and the same variable as argument and destination.
+ * This is feasible because the digit buffer is separate from the variable.
+ * ----------
+ */
+typedef struct NumericVar
+{
+ int ndigits; /* # of digits in digits[] - can be 0! */
+ int weight; /* weight of first digit */
+ int sign; /* NUMERIC_POS, _NEG, _NAN, _PINF, or _NINF */
+ int dscale; /* display scale */
+ NumericDigit *buf; /* start of palloc'd space for digits[] */
+ NumericDigit *digits; /* base-NBASE digits */
+} NumericVar;
+
/* The actual contents of Numeric are private to numeric.c */
struct NumericData;
typedef struct NumericData *Numeric;
@@ -79,9 +210,22 @@ NumericGetDatum(Numeric X)
#define PG_GETARG_NUMERIC_COPY(n) DatumGetNumericCopy(PG_GETARG_DATUM(n))
#define PG_RETURN_NUMERIC(x) return NumericGetDatum(x)
+#define init_var(v) memset(v, 0, sizeof(NumericVar))
+
/*
* Utility functions in numeric.c
*/
+extern void alloc_var(NumericVar *var, int ndigits);
+extern void free_var(NumericVar *var);
+extern void zero_var(NumericVar *var);
+
+extern void set_var_from_num(Numeric num, NumericVar *dest);
+extern void init_var_from_num(Numeric num, NumericVar *dest);
+extern void set_var_from_var(const NumericVar *value, NumericVar *dest);
+
+extern Numeric numeric_make_result(const NumericVar *var);
+extern Numeric numeric_make_result_opt_error(const NumericVar *var, bool *have_error);
+
extern bool numeric_is_nan(Numeric num);
extern bool numeric_is_inf(Numeric num);
extern int32 numeric_maximum_size(int32 typmod);
