1/*-------------------------------------------------------------------------
2 *
3 * numeric.h
4 * Definitions for the exact numeric data type of Postgres
5 *
6 * Original coding 1998, Jan Wieck. Heavily revised 2003, Tom Lane.
7 *
8 * Copyright (c) 1998-2019, PostgreSQL Global Development Group
9 *
10 * src/include/utils/numeric.h
11 *
12 *-------------------------------------------------------------------------
13 */
14#ifndef _PG_NUMERIC_H_
15#define _PG_NUMERIC_H_
16
17#include "fmgr.h"
18
19/*
20 * Limit on the precision (and hence scale) specifiable in a NUMERIC typmod.
21 * Note that the implementation limit on the length of a numeric value is
22 * much larger --- beware of what you use this for!
23 */
24#define NUMERIC_MAX_PRECISION 1000
25
26/*
27 * Internal limits on the scales chosen for calculation results
28 */
29#define NUMERIC_MAX_DISPLAY_SCALE NUMERIC_MAX_PRECISION
30#define NUMERIC_MIN_DISPLAY_SCALE 0
31
32#define NUMERIC_MAX_RESULT_SCALE (NUMERIC_MAX_PRECISION * 2)
33
34/*
35 * For inherently inexact calculations such as division and square root,
36 * we try to get at least this many significant digits; the idea is to
37 * deliver a result no worse than float8 would.
38 */
39#define NUMERIC_MIN_SIG_DIGITS 16
40
41/* The actual contents of Numeric are private to numeric.c */
42struct NumericData;
43typedef struct NumericData *Numeric;
44
45/*
46 * fmgr interface macros
47 */
48
49#define DatumGetNumeric(X) ((Numeric) PG_DETOAST_DATUM(X))
50#define DatumGetNumericCopy(X) ((Numeric) PG_DETOAST_DATUM_COPY(X))
51#define NumericGetDatum(X) PointerGetDatum(X)
52#define PG_GETARG_NUMERIC(n) DatumGetNumeric(PG_GETARG_DATUM(n))
53#define PG_GETARG_NUMERIC_COPY(n) DatumGetNumericCopy(PG_GETARG_DATUM(n))
54#define PG_RETURN_NUMERIC(x) return NumericGetDatum(x)
55
56/*
57 * Utility functions in numeric.c
58 */
59extern bool numeric_is_nan(Numeric num);
60int32 numeric_maximum_size(int32 typmod);
61extern char *numeric_out_sci(Numeric num, int scale);
62extern char *numeric_normalize(Numeric num);
63
64extern Numeric numeric_add_opt_error(Numeric num1, Numeric num2,
65 bool *have_error);
66extern Numeric numeric_sub_opt_error(Numeric num1, Numeric num2,
67 bool *have_error);
68extern Numeric numeric_mul_opt_error(Numeric num1, Numeric num2,
69 bool *have_error);
70extern Numeric numeric_div_opt_error(Numeric num1, Numeric num2,
71 bool *have_error);
72extern Numeric numeric_mod_opt_error(Numeric num1, Numeric num2,
73 bool *have_error);
74extern int32 numeric_int4_opt_error(Numeric num, bool *error);
75
76#endif /* _PG_NUMERIC_H_ */
77