Safe Namespace Reference

Arithmetic operations with overflow checks. More...

Namespaces
	Internal
	Helper functions for providing integer overflow checks.

Functions
template<typename T >
T	add (T summand_1, T summand_2)
	Safe addition, throws an exception on overflow. More...

Detailed Description

Arithmetic operations with overflow checks.

Function Documentation

add()

template<typename T >

T Safe::add	(	T	summand_1,
		T	summand_2
	)

Safe addition, throws an exception on overflow.

This function returns the result of summand_1 and summand_2 only when the operation would not overflow, otherwise an exception of type std::overflow_error is thrown.

Parameters

[in]

summand_1,summand_2

summands to be summed up

Returns

the sum of summand_1 and summand_2

Exceptions

std::overflow_error

if the addition would overflow

This function utilizes compiler builtins when available and should have a very small performance hit then. When builtins are unavailable, a more extensive check is required.

Builtins are available for the following configurations:

• GCC/Clang for signed and unsigned int, long and long long (not char & short)
• MSVC for unsigned int, long and long long

Referenced by Exiv2::PsdImage::readMetadata().