/* ------------------------------------------------------------------ */ | |
/* Decimal Context module header */ | |
/* ------------------------------------------------------------------ */ | |
/* Copyright (c) IBM Corporation, 2000, 2010. 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, on the General Decimal Arithmetic page. */ | |
/* */ | |
/* 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 */ | |
/* ------------------------------------------------------------------ */ | |
/* */ | |
/* Context variables must always have valid values: */ | |
/* */ | |
/* status -- [any bits may be cleared, but not set, by user] */ | |
/* round -- must be one of the enumerated rounding modes */ | |
/* */ | |
/* The following variables are implied for fixed size formats (i.e., */ | |
/* they are ignored) but should still be set correctly in case used */ | |
/* with decNumber functions: */ | |
/* */ | |
/* clamp -- must be either 0 or 1 */ | |
/* digits -- must be in the range 1 through 999999999 */ | |
/* emax -- must be in the range 0 through 999999999 */ | |
/* emin -- must be in the range 0 through -999999999 */ | |
/* extended -- must be either 0 or 1 [present only if DECSUBSET] */ | |
/* traps -- only defined bits may be set */ | |
/* */ | |
/* ------------------------------------------------------------------ */ | |
#if !defined(DECCONTEXT) | |
#define DECCONTEXT | |
#define DECCNAME "decContext" /* Short name */ | |
#define DECCFULLNAME "Decimal Context Descriptor" /* Verbose name */ | |
#define DECCAUTHOR "Mike Cowlishaw" /* Who to blame */ | |
#if !defined(int32_t) | |
#include <stdint.h> /* C99 standard integers */ | |
#endif | |
#include <stdio.h> /* for printf, etc. */ | |
#include <signal.h> /* for traps */ | |
/* Extended flags setting -- set this to 0 to use only IEEE flags */ | |
#if !defined(DECEXTFLAG) | |
#define DECEXTFLAG 1 /* 1=enable extended flags */ | |
#endif | |
/* Conditional code flag -- set this to 0 for best performance */ | |
#if !defined(DECSUBSET) | |
#define DECSUBSET 0 /* 1=enable subset arithmetic */ | |
#endif | |
/* Context for operations, with associated constants */ | |
enum rounding { | |
DEC_ROUND_CEILING, /* round towards +infinity */ | |
DEC_ROUND_UP, /* round away from 0 */ | |
DEC_ROUND_HALF_UP, /* 0.5 rounds up */ | |
DEC_ROUND_HALF_EVEN, /* 0.5 rounds to nearest even */ | |
DEC_ROUND_HALF_DOWN, /* 0.5 rounds down */ | |
DEC_ROUND_DOWN, /* round towards 0 (truncate) */ | |
DEC_ROUND_FLOOR, /* round towards -infinity */ | |
DEC_ROUND_05UP, /* round for reround */ | |
DEC_ROUND_MAX /* enum must be less than this */ | |
}; | |
#define DEC_ROUND_DEFAULT DEC_ROUND_HALF_EVEN; | |
typedef struct { | |
int32_t digits; /* working precision */ | |
int32_t emax; /* maximum positive exponent */ | |
int32_t emin; /* minimum negative exponent */ | |
enum rounding round; /* rounding mode */ | |
uint32_t traps; /* trap-enabler flags */ | |
uint32_t status; /* status flags */ | |
uint8_t clamp; /* flag: apply IEEE exponent clamp */ | |
#if DECSUBSET | |
uint8_t extended; /* flag: special-values allowed */ | |
#endif | |
} decContext; | |
/* Maxima and Minima for context settings */ | |
#define DEC_MAX_DIGITS 999999999 | |
#define DEC_MIN_DIGITS 1 | |
#define DEC_MAX_EMAX 999999999 | |
#define DEC_MIN_EMAX 0 | |
#define DEC_MAX_EMIN 0 | |
#define DEC_MIN_EMIN -999999999 | |
#define DEC_MAX_MATH 999999 /* max emax, etc., for math funcs. */ | |
/* Classifications for decimal numbers, aligned with 754 (note that */ | |
/* 'normal' and 'subnormal' are meaningful only with a decContext */ | |
/* or a fixed size format). */ | |
enum decClass { | |
DEC_CLASS_SNAN, | |
DEC_CLASS_QNAN, | |
DEC_CLASS_NEG_INF, | |
DEC_CLASS_NEG_NORMAL, | |
DEC_CLASS_NEG_SUBNORMAL, | |
DEC_CLASS_NEG_ZERO, | |
DEC_CLASS_POS_ZERO, | |
DEC_CLASS_POS_SUBNORMAL, | |
DEC_CLASS_POS_NORMAL, | |
DEC_CLASS_POS_INF | |
}; | |
/* Strings for the decClasses */ | |
#define DEC_ClassString_SN "sNaN" | |
#define DEC_ClassString_QN "NaN" | |
#define DEC_ClassString_NI "-Infinity" | |
#define DEC_ClassString_NN "-Normal" | |
#define DEC_ClassString_NS "-Subnormal" | |
#define DEC_ClassString_NZ "-Zero" | |
#define DEC_ClassString_PZ "+Zero" | |
#define DEC_ClassString_PS "+Subnormal" | |
#define DEC_ClassString_PN "+Normal" | |
#define DEC_ClassString_PI "+Infinity" | |
#define DEC_ClassString_UN "Invalid" | |
/* Trap-enabler and Status flags (exceptional conditions), and */ | |
/* their names. The top byte is reserved for internal use */ | |
#if DECEXTFLAG | |
/* Extended flags */ | |
#define DEC_Conversion_syntax 0x00000001 | |
#define DEC_Division_by_zero 0x00000002 | |
#define DEC_Division_impossible 0x00000004 | |
#define DEC_Division_undefined 0x00000008 | |
#define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ | |
#define DEC_Inexact 0x00000020 | |
#define DEC_Invalid_context 0x00000040 | |
#define DEC_Invalid_operation 0x00000080 | |
#if DECSUBSET | |
#define DEC_Lost_digits 0x00000100 | |
#endif | |
#define DEC_Overflow 0x00000200 | |
#define DEC_Clamped 0x00000400 | |
#define DEC_Rounded 0x00000800 | |
#define DEC_Subnormal 0x00001000 | |
#define DEC_Underflow 0x00002000 | |
#else | |
/* IEEE flags only */ | |
#define DEC_Conversion_syntax 0x00000010 | |
#define DEC_Division_by_zero 0x00000002 | |
#define DEC_Division_impossible 0x00000010 | |
#define DEC_Division_undefined 0x00000010 | |
#define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ | |
#define DEC_Inexact 0x00000001 | |
#define DEC_Invalid_context 0x00000010 | |
#define DEC_Invalid_operation 0x00000010 | |
#if DECSUBSET | |
#define DEC_Lost_digits 0x00000000 | |
#endif | |
#define DEC_Overflow 0x00000008 | |
#define DEC_Clamped 0x00000000 | |
#define DEC_Rounded 0x00000000 | |
#define DEC_Subnormal 0x00000000 | |
#define DEC_Underflow 0x00000004 | |
#endif | |
/* IEEE 754 groupings for the flags */ | |
/* [DEC_Clamped, DEC_Lost_digits, DEC_Rounded, and DEC_Subnormal */ | |
/* are not in IEEE 754] */ | |
#define DEC_IEEE_754_Division_by_zero (DEC_Division_by_zero) | |
#if DECSUBSET | |
#define DEC_IEEE_754_Inexact (DEC_Inexact | DEC_Lost_digits) | |
#else | |
#define DEC_IEEE_754_Inexact (DEC_Inexact) | |
#endif | |
#define DEC_IEEE_754_Invalid_operation (DEC_Conversion_syntax | \ | |
DEC_Division_impossible | \ | |
DEC_Division_undefined | \ | |
DEC_Insufficient_storage | \ | |
DEC_Invalid_context | \ | |
DEC_Invalid_operation) | |
#define DEC_IEEE_754_Overflow (DEC_Overflow) | |
#define DEC_IEEE_754_Underflow (DEC_Underflow) | |
/* flags which are normally errors (result is qNaN, infinite, or 0) */ | |
#define DEC_Errors (DEC_IEEE_754_Division_by_zero | \ | |
DEC_IEEE_754_Invalid_operation | \ | |
DEC_IEEE_754_Overflow | DEC_IEEE_754_Underflow) | |
/* flags which cause a result to become qNaN */ | |
#define DEC_NaNs DEC_IEEE_754_Invalid_operation | |
/* flags which are normally for information only (finite results) */ | |
#if DECSUBSET | |
#define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact \ | |
| DEC_Lost_digits) | |
#else | |
#define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact) | |
#endif | |
/* IEEE 854 names (for compatibility with older decNumber versions) */ | |
#define DEC_IEEE_854_Division_by_zero DEC_IEEE_754_Division_by_zero | |
#define DEC_IEEE_854_Inexact DEC_IEEE_754_Inexact | |
#define DEC_IEEE_854_Invalid_operation DEC_IEEE_754_Invalid_operation | |
#define DEC_IEEE_854_Overflow DEC_IEEE_754_Overflow | |
#define DEC_IEEE_854_Underflow DEC_IEEE_754_Underflow | |
/* Name strings for the exceptional conditions */ | |
#define DEC_Condition_CS "Conversion syntax" | |
#define DEC_Condition_DZ "Division by zero" | |
#define DEC_Condition_DI "Division impossible" | |
#define DEC_Condition_DU "Division undefined" | |
#define DEC_Condition_IE "Inexact" | |
#define DEC_Condition_IS "Insufficient storage" | |
#define DEC_Condition_IC "Invalid context" | |
#define DEC_Condition_IO "Invalid operation" | |
#if DECSUBSET | |
#define DEC_Condition_LD "Lost digits" | |
#endif | |
#define DEC_Condition_OV "Overflow" | |
#define DEC_Condition_PA "Clamped" | |
#define DEC_Condition_RO "Rounded" | |
#define DEC_Condition_SU "Subnormal" | |
#define DEC_Condition_UN "Underflow" | |
#define DEC_Condition_ZE "No status" | |
#define DEC_Condition_MU "Multiple status" | |
#define DEC_Condition_Length 21 /* length of the longest string, */ | |
/* including terminator */ | |
/* Initialization descriptors, used by decContextDefault */ | |
#define DEC_INIT_BASE 0 | |
#define DEC_INIT_DECIMAL32 32 | |
#define DEC_INIT_DECIMAL64 64 | |
#define DEC_INIT_DECIMAL128 128 | |
/* Synonyms */ | |
#define DEC_INIT_DECSINGLE DEC_INIT_DECIMAL32 | |
#define DEC_INIT_DECDOUBLE DEC_INIT_DECIMAL64 | |
#define DEC_INIT_DECQUAD DEC_INIT_DECIMAL128 | |
/* decContext routines */ | |
extern decContext * decContextClearStatus(decContext *, uint32_t); | |
extern decContext * decContextDefault(decContext *, int32_t); | |
extern enum rounding decContextGetRounding(decContext *); | |
extern uint32_t decContextGetStatus(decContext *); | |
extern decContext * decContextRestoreStatus(decContext *, uint32_t, uint32_t); | |
extern uint32_t decContextSaveStatus(decContext *, uint32_t); | |
extern decContext * decContextSetRounding(decContext *, enum rounding); | |
extern decContext * decContextSetStatus(decContext *, uint32_t); | |
extern decContext * decContextSetStatusFromString(decContext *, const char *); | |
extern decContext * decContextSetStatusFromStringQuiet(decContext *, const char *); | |
extern decContext * decContextSetStatusQuiet(decContext *, uint32_t); | |
extern const char * decContextStatusToString(const decContext *); | |
extern int32_t decContextTestEndian(uint8_t); | |
extern uint32_t decContextTestSavedStatus(uint32_t, uint32_t); | |
extern uint32_t decContextTestStatus(decContext *, uint32_t); | |
extern decContext * decContextZeroStatus(decContext *); | |
#endif |