%% options copyright owner = Dirk Krause copyright year = 2015-xxxx license = bsd %% header /** @file Arithmetic operations on unsigned long. 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 long dk4ma_ulong_add(unsigned long a, unsigned long 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 long dk4ma_ulong_sub(unsigned long a, unsigned long 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 long dk4ma_ulong_mul(unsigned long a, unsigned long 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, ULONG_MAX on division by zero (see the ec component of erp). Error codes: DK4_E_DIVZERO. */ unsigned long dk4ma_ulong_div(unsigned long a, unsigned long b, dk4_er_t *erp); #ifdef __cplusplus } #endif %% module #include "dk4conf.h" #include "dk4types.h" #include "dk4error.h" #include "dk4numco.h" #include "dk4maaul.h" $!trace-include unsigned long dk4ma_ulong_add(unsigned long a, unsigned long b, dk4_er_t *erp) { $? "+ dk4ma_ulong_add %lu %lu", a, b $? ". ULONG_MAX = %lu", ULONG_MAX $? ". ULONG_MAX - a = %lu", (ULONG_MAX - a) $? ". b = %lu", b if ((ULONG_MAX - a) < b) { $? "! overflow" dk4error_set_simple_error_code(erp, DK4_E_MATH_OVERFLOW); } $? "- dk4ma_ulong_add %lu", (a+b) return (unsigned long)(a + b); } unsigned long dk4ma_ulong_sub(unsigned long a, unsigned long b, dk4_er_t *erp) { if (b > a) { dk4error_set_simple_error_code(erp, DK4_E_MATH_OVERFLOW); } return (unsigned long)(a - b); } unsigned long dk4ma_ulong_mul(unsigned long a, unsigned long b, dk4_er_t *erp) { if (0UL < a) { if ((ULONG_MAX / a) < b) { dk4error_set_simple_error_code(erp, DK4_E_MATH_OVERFLOW); } } return (unsigned long)(a * b); } unsigned long dk4ma_ulong_div(unsigned long a, unsigned long b, dk4_er_t *erp) { if (0UL < b) { return (unsigned long)(a / b); } else { dk4error_set_simple_error_code(erp, DK4_E_MATH_DIVZERO); return (unsigned long)(ULONG_MAX); } }