Internal conversion functions

Macros
#define	STRNUM_INTBUF   66
	Buffer size for integer-to-string conversion (64-bit binary + sign + null terminator)
#define	STRNUM_FPDIGITS   18
	Maximum meaningful floating-point digits (53-bit mantissa precision)
#define	STRNUM_FPBUF   25
	Buffer size for floating-point-to-string conversion (sign + digits + exponent + null)

Functions
uint8 *	_strnum_u64toa (uint8 buf[STRNUM_INTBUF], uint32 *len, uint64 value, uint16 base, uint32 mindigits, char sign, bool upper)
uint32	_strnum_f64toa (float64 d, uint8 dest[STRNUM_FPBUF])
uint32	_strnum_f32toa (float32 f, uint8 dest[STRNUM_FPBUF])
int32	_strnum_grisu2_32 (float32 f, uint8 *digits, int32 *K)
int32	_strnum_grisu2_64 (float64 d, uint8 *digits, int32 *K)

Detailed Description

Low-level helpers used by the format module and other internal components. They work with fixed-size buffers and return raw digit arrays. Most code should use the higher-level str* functions above.

Function Documentation

_strnum_f32toa()

uint32 _strnum_f32toa	(	float32	f,
		uint8	dest[STRNUM_FPBUF]
	)

Converts a 32-bit float to ASCII string

Like _strnum_f64toa(), but for single-precision floats.

Parameters

f	Float value to convert
dest	Buffer to write result (STRNUM_FPBUF bytes)

Returns

Length of resulting string (excluding null terminator)

_strnum_f64toa()

uint32 _strnum_f64toa	(	float64	d,
		uint8	dest[STRNUM_FPBUF]
	)

Converts a 64-bit float to ASCII string

Internal function using Grisu2 algorithm. Automatically selects format (plain, decimal, or scientific notation) and handles special values.

Parameters

d	Double value to convert
dest	Buffer to write result (STRNUM_FPBUF bytes)

Returns

Length of resulting string (excluding null terminator)

_strnum_grisu2_32()

int32 _strnum_grisu2_32	(	float32	f,
		uint8 *	digits,
		int32 *	K
	)

Low-level Grisu2 algorithm for 32-bit float

Extracts decimal digits and exponent for a float. This is the core of the Grisu2 algorithm and is used internally by _strnum_f32toa().

Parameters

f	Float value to convert
digits	Buffer to receive decimal digits (no decimal point, 18 bytes)
K	Pointer to exponent value (input/output)

Returns

Number of significant digits written to the digits buffer

_strnum_grisu2_64()

int32 _strnum_grisu2_64	(	float64	d,
		uint8 *	digits,
		int32 *	K
	)

Low-level Grisu2 algorithm for 64-bit double

Like _strnum_grisu2_32(), but for double-precision values.

Parameters

d	Double value to convert
digits	Buffer to receive decimal digits (no decimal point, 18 bytes)
K	Pointer to exponent value (input/output)

Returns

Number of significant digits written to the digits buffer

_strnum_u64toa()

uint8 * _strnum_u64toa	(	uint8	buf[STRNUM_INTBUF],
		uint32 *	len,
		uint64	value,
		uint16	base,
		uint32	mindigits,
		char	sign,
		bool	upper
	)

Converts a 64-bit unsigned integer to ASCII digits

Internal function for integer formatting. Converts the value to the specified base and writes ASCII digits into the provided buffer, returning a pointer to the start of the converted string within the buffer.

Parameters

buf	Fixed-size buffer (STRNUM_INTBUF bytes) to write into
len	Optional pointer to receive the length of the result (excluding null terminator)
value	Value to convert
base	Numeric base (2-36)
mindigits	Minimum number of digits (zero-padded if necessary)
sign	Sign character to prepend (0 for none, '-' or '+' typically)
upper	If true, use uppercase letters for bases > 10; if false, use lowercase

Returns

Pointer into buf where the converted string starts (null-terminated)