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/* ------------------------------------------------------------------ */
/* Decimal 128-bit format module header */
/* ------------------------------------------------------------------ */
/* Copyright (c) IBM Corporation, 2000, 2005. All rights reserved. */
/* */
/* This software is made available under the terms of the */
/* ICU License -- ICU 1.8.1 and later. */
/* */
/* The description and User's Guide ("The decNumber C Library") for */
/* this software is called decNumber.pdf. This document is */
/* available, together with arithmetic and format specifications, */
/* testcases, and Web links, at: http://www2.hursley.ibm.com/decimal */
/* */
/* Please send comments, suggestions, and corrections to the author: */
/* mfc@uk.ibm.com */
/* Mike Cowlishaw, IBM Fellow */
/* IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK */
/* ------------------------------------------------------------------ */
#if !defined(DECIMAL128)
#define DECIMAL128
#define DEC128NAME "decimal128" /* Short name */
#define DEC128FULLNAME "Decimal 128-bit Number" /* Verbose name */
#define DEC128AUTHOR "Mike Cowlishaw" /* Who to blame */
/* parameters for decimal128s */
#define DECIMAL128_Bytes 16 // length
#define DECIMAL128_Pmax 34 // maximum precision (digits)
#define DECIMAL128_Emax 6144 // maximum adjusted exponent
#define DECIMAL128_Emin -6143 // minimum adjusted exponent
#define DECIMAL128_Bias 6176 // bias for the exponent
#define DECIMAL128_String 43 // maximum string length, +1
#define DECIMAL128_EconL 12 // exponent continuation length
// highest biased exponent (Elimit-1)
#define DECIMAL128_Ehigh (DECIMAL128_Emax+DECIMAL128_Bias-DECIMAL128_Pmax+1)
// check enough digits, if pre-defined
#if defined(DECNUMDIGITS)
#if (DECNUMDIGITS<DECIMAL128_Pmax)
#error decimal128.h needs pre-defined DECNUMDIGITS>=34 for safe use
#endif
#endif
#ifndef DECNUMDIGITS
#define DECNUMDIGITS DECIMAL128_Pmax // size if not already defined
#endif
#ifndef DECNUMBER
#include "decNumber.h" // context and number library
#endif
/* Decimal 128-bit type, accessible by bytes */
typedef struct {
uint8_t bytes[DECIMAL128_Bytes]; // decimal128: 1, 5, 12, 110 bits
} decimal128;
/* special values [top byte excluding sign bit; last two bits are
don't-care for Infinity on input, last bit don't-care for NaN] */
#if !defined(DECIMAL_NaN)
#define DECIMAL_NaN 0x7c // 0 11111 00 NaN
#define DECIMAL_sNaN 0x7e // 0 11111 10 sNaN
#define DECIMAL_Inf 0x78 // 0 11110 00 Infinity
#endif
/* Macros for accessing decimal128 fields. These assume the argument
is a reference (pointer) to the decimal128 structure, and the
decimal128 is in network byte order (big-endian) */
// Get sign
#define decimal128Sign(d) ((unsigned)(d)->bytes[0]>>7)
// Get combination field
#define decimal128Comb(d) (((d)->bytes[0] & 0x7c)>>2)
// Get exponent continuation [does not remove bias]
#define decimal128ExpCon(d) ((((d)->bytes[0] & 0x03)<<10) \
| ((unsigned)(d)->bytes[1]<<2) \
| ((unsigned)(d)->bytes[2]>>6))
// Set sign [this assumes sign previously 0]
#define decimal128SetSign(d, b) { \
(d)->bytes[0]|=((unsigned)(b)<<7);}
// Set exponent continuation [does not apply bias]
// This assumes range has been checked and exponent previously 0;
// type of exponent must be unsigned
#define decimal128SetExpCon(d, e) { \
(d)->bytes[0]|=(uint8_t)((e)>>10); \
(d)->bytes[1] =(uint8_t)(((e)&0x3fc)>>2); \
(d)->bytes[2]|=(uint8_t)(((e)&0x03)<<6);}
/* ------------------------------------------------------------------ */
/* Routines */
/* ------------------------------------------------------------------ */
// String conversions
decimal128 * decimal128FromString(decimal128 *, const char *, decContext *);
char * decimal128ToString(const decimal128 *, char *);
char * decimal128ToEngString(const decimal128 *, char *);
// decNumber conversions
decimal128 * decimal128FromNumber(decimal128 *, const decNumber *,
decContext *);
decNumber * decimal128ToNumber(const decimal128 *, decNumber *);
#endif
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