wsieee754.h
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- /*
- *
- * wsieee754.h
- *
- * Author: Markku Rossi <mtr@iki.fi>
- *
- * Copyright (c) 2000 WAPIT OY LTD.
- * All rights reserved.
- *
- * Functions to manipulate ANSI/IEEE Std 754-1985 binary floating-point
- * numbers.
- *
- */
- #ifndef WSIEEE754_H
- #define WSIEEE754_H
- /********************* Types and definitions ****************************/
- /* Return codes for encoding and decoding functions. */
- typedef enum
- {
- /* The operation was successful. */
- WS_IEEE754_OK,
- /* The value is `Not a Number' NaN. */
- WS_IEEE754_NAN,
- /* The valueis positive infinity. */
- WS_IEEE754_POSITIVE_INF,
- /* The value is negative infinity. */
- WS_IEEE754_NEGATIVE_INF
- } WsIeee754Result;
- /********************* Special values ***********************************/
- /* `Not a Number' NaN */
- extern unsigned char ws_ieee754_nan[4];
- /* Positive infinity. */
- extern unsigned char ws_ieee754_positive_inf[4];
- /* Positive infinity. */
- extern unsigned char ws_ieee754_negative_inf[4];
- /********************* Global functions *********************************/
- /* Encode the floating point number `value' to the IEEE-754 single
- precision format. The function stores the encoded value to the
- buffer `buf'. The buffer `buf' must have 32 bits (4 bytes) of
- space. The function returns WsIeee754Result return value. It
- describes the format of the encoded value in `buf'. In all cases,
- the function generates the corresponding encoded value to the
- buffer `buf'. */
- WsIeee754Result ws_ieee754_encode_single(double value, unsigned char *buf);
- /* Decode the IEEE-754 encoded number `buf' into a floating point
- number. The argument `buf' must have 32 bits of data. The
- function returns a result code which describes the success of the
- decode operation. If the result is WS_IEEE754_OK, the resulting
- floating point number is returned in `value_return'. */
- WsIeee754Result ws_ieee754_decode_single(unsigned char *buf,
- double *value_return);
- /* Get the sign bit from the IEEE-754 single format encoded number
- `buf'. The buffer `buf' must have 32 bits of data. */
- WsUInt32 ws_ieee754_single_get_sign(unsigned char *buf);
- /* Get the exponent from the IEEE-754 single format encoded number
- `buf'. The buffer `buf' must have 32 bits of data. The returned
- value is the biased exponent. */
- WsUInt32 ws_ieee754_single_get_exp(unsigned char *buf);
- /* Get the mantissa from the IEEE-754 single format encoded number
- `buf'. The buffer `buf' must have 32 bits of data. */
- WsUInt32 ws_ieee754_single_get_mant(unsigned char *buf);
- #endif /* not WSIEEE754_H */