1 // vim: filetype=c:tabstop=4:ai:expandtab
2 // SPDX-License-Identifier: ICU
3 // scspell-id: ba161c23-f62c-11ec-b4ce-80ee73e9b8e7
4 /* ------------------------------------------------------------------ */
5 /* Decimal 32-bit format module header */
6 /* ------------------------------------------------------------------ */
7 /* Copyright (c) IBM Corporation, 2000, 2006. All rights reserved. */
8 /* */
9 /* This software is made available under the terms of the */
10 /* ICU License -- ICU 1.8.1 and later. */
11 /* */
12 /* The description and User's Guide ("The decNumber C Library") for */
13 /* this software is called decNumber.pdf. This document is */
14 /* available, together with arithmetic and format specifications, */
15 /* testcases, and Web links, on the General Decimal Arithmetic page. */
16 /* */
17 /* Please send comments, suggestions, and corrections to the author: */
18 /* mfc@uk.ibm.com */
19 /* Mike Cowlishaw, IBM Fellow */
20 /* IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK */
21 /* ------------------------------------------------------------------ */
22
23 #if !defined(DECIMAL32)
24 # define DECIMAL32
25 # define DEC32NAME "decimal32" /* Short name */
26 # define DEC32FULLNAME "Decimal 32-bit Number" /* Verbose name */
27 # define DEC32AUTHOR "Mike Cowlishaw" /* Who to blame */
28
29 /* parameters for decimal32s */
30 # define DECIMAL32_Bytes 4 /* length */
31 # define DECIMAL32_Pmax 7 /* maximum precision (digits) */
32 # define DECIMAL32_Emax 96 /* maximum adjusted exponent */
33 # define DECIMAL32_Emin -95 /* minimum adjusted exponent */
34 # define DECIMAL32_Bias 101 /* bias for the exponent */
35 # define DECIMAL32_String 15 /* maximum string length, +1 */
36 # define DECIMAL32_EconL 6 /* exp. continuation length */
37 /* highest biased exponent (Elimit-1) */
38 # define DECIMAL32_Ehigh \
39 (DECIMAL32_Emax+DECIMAL32_Bias-DECIMAL32_Pmax+1)
40
41 /* check enough digits, if pre-defined */
42 # if defined(DECNUMDIGITS)
43 # if (DECNUMDIGITS<DECIMAL32_Pmax)
44 # error decimal32.h needs pre-defined DECNUMDIGITS>=7 for safe use
45 # endif
46 # endif
47
48 # ifndef DECNUMDIGITS
49 # define DECNUMDIGITS DECIMAL32_Pmax /* size if not already defined */
50 # endif
51 # ifndef DECNUMBER
52 # include "decNumber.h" /* context and number library */
53 # endif
54
55 /* Decimal 32-bit type, accessible by bytes */
56 typedef struct {
57 uint8_t bytes[DECIMAL32_Bytes]; /* decimal32: 1, 5, 6, 20 bits */
58 } decimal32;
59
60 /* special values [top byte excluding sign bit; last two bits are */
61 /* don't-care for Infinity on input, last bit don't-care for NaN] */
62 # if !defined(DECIMAL_NaN)
63 # define DECIMAL_NaN 0x7c /* 0 11111 00 NaN */
64 # define DECIMAL_sNaN 0x7e /* 0 11111 10 sNaN */
65 # define DECIMAL_Inf 0x78 /* 0 11110 00 Infinity */
66 # endif
67
68 /* ---------------------------------------------------------------- */
69 /* Routines */
70 /* ---------------------------------------------------------------- */
71 /* String conversions */
72 decimal32 * decimal32FromString(decimal32 *, const char *,
73 decContext *);
74 char * decimal32ToString(const decimal32 *, char *);
75 char * decimal32ToEngString(const decimal32 *, char *);
76
77 /* decNumber conversions */
78 decimal32 * decimal32FromNumber(decimal32 *, const decNumber *,
79 decContext *);
80 decNumber * decimal32ToNumber(const decimal32 *, decNumber *);
81
82 /* Format-dependent utilities */
83 uint32_t decimal32IsCanonical(const decimal32 *);
84 decimal32 * decimal32Canonical(decimal32 *, const decimal32 *);
85
86 #endif