%% options copyright owner = Dirk Krause copyright year = 2015-xxxx license = bsd %% header /** @file Arithmetic operations on unsigned char. CRT on Windows: Optional. */ #ifndef DK4CONF_H_INCLUDED #include "dk4conf.h" #endif #ifndef DK4TYPES_H_INCLUDED #include "dk4types.h" #endif #ifndef DK4ERROR_H_INCLUDED #include "dk4error.h" #endif #ifdef __cplusplus extern "C" { #endif /** Addition. @param a Left operand. @param b Right operand. @param erp Error report, may be NULL. @return Result on success, least significant result bits on overflow (see ec component of erp). Error codes: DK4_E_OVERFLOW. */ unsigned char dk4ma_uchar_add(unsigned char a, unsigned char b, dk4_er_t *erp); /** Subtraction. @param a Left operand. @param b Right operand. @param erp Error report, may be NULL. @return Result on success, least significant result bits on overflow (see ec component of erp). Error codes: DK4_E_OVERFLOW. */ unsigned char dk4ma_uchar_sub(unsigned char a, unsigned char b, dk4_er_t *erp); /** Multiplication. @param a Left factor. @param b right factor. @param erp Error report, may be NULL. @return Result on success, least significant bits on overflow (see ec component of erp). Error codes: DK4_E_OVERFLOW. */ unsigned char dk4ma_uchar_mul(unsigned char a, unsigned char b, dk4_er_t *erp); /** Division. @param a Counter (left operand). @param b Denominator (right operand). @param erp Error report, may be NULL. @return Division result on success, UCHAR_MAX on division by zero (see the ec component of erp). Error codes: DK4_E_DIVZERO. */ unsigned char dk4ma_uchar_div(unsigned char a, unsigned char b, dk4_er_t *erp); #ifdef __cplusplus } #endif %% module #include "dk4conf.h" #include "dk4types.h" #include "dk4error.h" #include "dk4numco.h" #include "dk4maauc.h" unsigned char dk4ma_uchar_add(unsigned char a, unsigned char b, dk4_er_t *erp) { if ((UCHAR_MAX - a) < b) { dk4error_set_simple_error_code(erp, DK4_E_MATH_OVERFLOW); } return (unsigned char)(a + b); } unsigned char dk4ma_uchar_sub(unsigned char a, unsigned char b, dk4_er_t *erp) { if (b > a) { dk4error_set_simple_error_code(erp, DK4_E_MATH_OVERFLOW); } return (unsigned char)(a - b); } unsigned char dk4ma_uchar_mul(unsigned char a, unsigned char b, dk4_er_t *erp) { if (0 < a) { if ((UCHAR_MAX / a) < b) { dk4error_set_simple_error_code(erp, DK4_E_MATH_OVERFLOW); } } return (unsigned char)(a * b); } unsigned char dk4ma_uchar_div(unsigned char a, unsigned char b, dk4_er_t *erp) { if (0 < b) { return (unsigned char)(a / b); } else { dk4error_set_simple_error_code(erp, DK4_E_MATH_DIVZERO); return (unsigned char)(UCHAR_MAX); } }