Overflowing arithmetic

Collaboration diagram for Overflowing arithmetic:

Macros
#define	add_overflow(a, b, r)
	Overflowing addition.
#define	mul_overflow(a, b, r)
	Overflowing multiplication.

Functions
static bool	uadd_overflow (unsigned a, unsigned b, unsigned *res)
static bool	uaddl_overflow (unsigned long a, unsigned long b, unsigned long *res)
static bool	uaddll_overflow (unsigned long long a, unsigned long long b, unsigned long long *res)
static bool	umul_overflow (unsigned a, unsigned b, unsigned *res)
static bool	umull_overflow (unsigned long a, unsigned long b, unsigned long *res)
static bool	umulll_overflow (unsigned long long a, unsigned long long b, unsigned long long *res)

Detailed Description

Macro Definition Documentation

add_overflow

#define add_overflow	(		a,
			b,
			r )

Value:

    _Generic(*(r), \
        unsigned: uadd_overflow(a, b, (unsigned *)(r)), \
        unsigned long: uaddl_overflow(a, b, (unsigned long *)(r)), \
        unsigned long long: uaddll_overflow(a, b, (unsigned long long *)(r)))

Overflowing addition.

Converts a and b to the type of *r. Then computes the sum of both conversions while checking for overflow. Finally stores the result in *r.

Parameters

a	an integer
b	an integer
r	a pointer to an integer [OUT]

Return values

false	The sum did not overflow.
true	The sum overflowed.

mul_overflow

#define mul_overflow	(		a,
			b,
			r )

Value:

    _Generic(*(r), \
        unsigned: umul_overflow(a, b, (unsigned *)(r)), \
        unsigned long: umull_overflow(a, b, (unsigned long *)(r)), \
        unsigned long long: umulll_overflow(a, b, (unsigned long long *)(r)))

Overflowing multiplication.

Converts a and b to the type of *r. Then computes the product of both conversions while checking for overflow. Finally stores the result in *r.

Parameters

a	an integer
b	an integer
r	a pointer to an integer [OUT]

Return values

false	The product did not overflow.
true	The product overflowed.

Referenced by vlc_alloc(), and vlc_reallocarray().

Function Documentation

uadd_overflow()

bool uadd_overflow ( unsigned a, unsigned b, unsigned * res )

inlinestatic

uaddl_overflow()

bool uaddl_overflow ( unsigned long a, unsigned long b, unsigned long * res )

inlinestatic

uaddll_overflow()

bool uaddll_overflow ( unsigned long long a, unsigned long long b, unsigned long long * res )

inlinestatic

umul_overflow()

bool umul_overflow ( unsigned a, unsigned b, unsigned * res )

inlinestatic

umull_overflow()

bool umull_overflow ( unsigned long a, unsigned long b, unsigned long * res )

inlinestatic

umulll_overflow()

bool umulll_overflow ( unsigned long long a, unsigned long long b, unsigned long long * res )

inlinestatic