1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
// Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved.
// SPDX-License-Identifier: BSD-3-Clause
#ifndef STD_DTOA_H
#define STD_DTOA_H
//
// Constant Definitions
//
// For floating point numbers, the range of a double precision number is
// approximately +/- 10 ^ 308.25 as per the IEEE Standard 754.
// As such, the maximum size of the integer portion of the
// string is assumed to be 311 (309 + sign + \0). The maximum
// size of the fractional part is assumed to be 100. Thus, the
// maximum size of the string that would contain the number
// after conversion is safely assumed to be 420 (including any
// prefix, the null character and exponent specifiers 'e').
//
// The buffers that contain the converted integer and the fraction parts of
// the float are safely assumed to be of size 310.
#define STD_DTOA_FORMAT_FLOAT_SIZE 420
#define STD_DTOA_FORMAT_INTEGER_SIZE 311
#define STD_DTOA_FORMAT_FRACTION_SIZE 100
// Constants for operations on the IEEE 754 representation of double
// precision floating point numbers.
#define STD_DTOA_DP_SIGN_SHIFT_COUNT 63
#define STD_DTOA_DP_EXPONENT_SHIFT_COUNT 52
#define STD_DTOA_DP_EXPONENT_MASK 0x7ff
#define STD_DTOA_DP_EXPONENT_BIAS 1023
#define STD_DTOA_DP_MANTISSA_MASK ( ( (uint64_t)1 << 52 ) - 1 )
#define STD_DTOA_DP_INFINITY_EXPONENT_ID 0x7FF
#define STD_DTOA_DP_MAX_EXPONENT 1023
#define STD_DTOA_DP_MIN_EXPONENT_NORM -1022
#define STD_DTOA_DP_MIN_EXPONENT_DENORM -1074
#define STD_DTOA_DP_MAX_EXPONENT_DEC 308
#define STD_DTOA_DP_MIN_EXPONENT_DEC_DENORM -323
#define STD_DTOA_PRECISION_ROUNDING_VALUE 4
#define STD_DTOA_DEFAULT_FLOAT_PRECISION 6
#define STD_DTOA_NEGATIVE_INF_UPPER_CASE "-INF"
#define STD_DTOA_NEGATIVE_INF_LOWER_CASE "-inf"
#define STD_DTOA_POSITIVE_INF_UPPER_CASE "INF"
#define STD_DTOA_POSITIVE_INF_LOWER_CASE "inf"
#define STD_DTOA_NAN_UPPER_CASE "NAN"
#define STD_DTOA_NAN_LOWER_CASE "nan"
#define STD_DTOA_FP_POSITIVE_INF 0x7FF0000000000000uLL
#define STD_DTOA_FP_NEGATIVE_INF 0xFFF0000000000000uLL
#define STD_DTOA_FP_SNAN 0xFFF0000000000001uLL
#define STD_DTOA_FP_QNAN 0xFFFFFFFFFFFFFFFFuLL
//
// Useful Macros
//
#define MY_ISDIGIT(c) ( ( (c) >= '0' ) && ( (c) <= '9' ) )
#define FP_EXPONENT(u) ( ( ( (u) >> STD_DTOA_DP_EXPONENT_SHIFT_COUNT ) \
& STD_DTOA_DP_EXPONENT_MASK ) - STD_DTOA_DP_EXPONENT_BIAS )
#define FP_EXPONENT_BIASED(u) ( ( (u) >> STD_DTOA_DP_EXPONENT_SHIFT_COUNT ) \
& STD_DTOA_DP_EXPONENT_MASK )
#define FP_MANTISSA_NORM(u) ( ( (u) & STD_DTOA_DP_MANTISSA_MASK ) | \
( (uint64_t)1 << STD_DTOA_DP_EXPONENT_SHIFT_COUNT ) )
#define FP_MANTISSA_DENORM(u) ( (u) & STD_DTOA_DP_MANTISSA_MASK )
#define FP_MANTISSA(u) ( FP_EXPONENT_BIASED(u) ? FP_MANTISSA_NORM(u) : \
FP_MANTISSA_DENORM(u) )
#define FP_SIGN(u) ( (u) >> STD_DTOA_DP_SIGN_SHIFT_COUNT )
//
// Type Definitions
//
typedef enum
{
FP_TYPE_UNKOWN = 0,
FP_TYPE_NEGATIVE_INF,
FP_TYPE_POSITIVE_INF,
FP_TYPE_NAN,
FP_TYPE_GENERAL,
} FloatingPointType;
//
// Function Declarations
//
#ifdef __cplusplus
extern "C" {
#endif // #ifdef __cplusplus
double fp_pow_10( int nPow );
double fp_round( double dNumber, int nPrecision );
int fp_log_10( double dNumber );
int fp_check_special_cases( double dNumber, FloatingPointType* pNumberType );
int std_dtoa_decimal( double dNumber, int nPrecision,
char acIntegerPart[ STD_DTOA_FORMAT_INTEGER_SIZE ],
char acFractionPart[ STD_DTOA_FORMAT_FRACTION_SIZE ] );
int std_dtoa_hex( double dNumber, int nPrecision, char cFormat,
char acIntegerPart[ STD_DTOA_FORMAT_INTEGER_SIZE ],
char acFractionPart[ STD_DTOA_FORMAT_FRACTION_SIZE ],
int* pnExponent );
#ifdef __cplusplus
}
#endif // #ifdef __cplusplus
#endif // STD_DTOA_H
|
