Component bsls_byteorderutil_impl [Package bsls]

Provide implementation of byte-order manipulation functions. More...

Namespaces
namespace	bsls
Defines
#define	BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT(expr)
#define	BSLS_BYTEORDERUTIL_IMPL_DISABLE_COUNTERPRODUCTIVE_MACROS   1
#define	BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_16(dstType, x)
#define	BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_32(dstType, x)
#define	BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_64(dstType, x)

---

Detailed Description

Outline

• Purpose
• Classes
• Macros
• Description

Purpose:

Provide implementation of byte-order manipulation functions.

Classes:

bsls::ByteOrderUtil_Impl

namespace for swapping functions

Macros:

BSLS_BYTEORDERUTIL_IMPL_CUSTOMSWAP_16(x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_CUSTOMSWAP_32(x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_CUSTOMSWAP_64(x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_CUSTOMSWAP_P16(&x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_CUSTOMSWAP_P32(&x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_CUSTOMSWAP_P64(&x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_16(x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_32(x) return x with bytes swapped BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_64(x) return x with bytes swapped

See also:

Component bsls_byteorderutil, Component bsls_byteorder

Description:

This component provides a template class ByteOrderUtil_Impl and a set of macros suitable for swapping byte orders of all integral types. The *_CUSTOMSWAP_* macros use assembly language or compiler primitives, whereas the *_GENERICSWAP_* macros use C bitwise operations to perform the swap. The *_CUSTOMSWAP_* macros are not defined on all platforms; callers must perform an #ifdef to see if they are defined before calling them. At most one of *_CUSTOMSWAP_NN and *_CUSTOMSWAP_PNN are defined on any one platform for any value of NN, while *_GENERICSWAP_NN macros are defined on all platforms and are meant to be called when the other macros are not available, and are also used for benchmarking.

---

Define Documentation

#define BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT

(

expr

)

#define BSLS_BYTEORDERUTIL_IMPL_DISABLE_COUNTERPRODUCTIVE_MACROS   1

#define BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_16	(		dstType,
			x
	)

Value:

{                                                                         \
        BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT(2 == sizeof x);           \
        BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT(2 == sizeof(dstType));    \
                                                                              \
        return static_cast<dstType>((((x) & 0xff00u) >> 8) |                  \
                                    (((x) & 0x00ffu) << 8));                  \
    }

#define BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_32	(		dstType,
			x
	)

Value:

{                                                                         \
        BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT(4 == sizeof x);           \
        BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT(4 == sizeof(dstType));    \
                                                                              \
        return static_cast<dstType>((((x) & 0x000000ffU) << 24)               \
                                  | (((x) & 0x0000ff00U) <<  8)               \
                                  | (((x) & 0x00ff0000U) >>  8)               \
                                  | (((x) & 0xff000000U) >> 24));             \
    }

#define BSLS_BYTEORDERUTIL_IMPL_GENERICSWAP_64	(		dstType,
			x
	)

Value:

{                                                                         \
        BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT(8 == sizeof x);           \
        BSLS_BYTEORDERUTIL_IMPL_COMPILE_TIME_ASSERT(8 == sizeof(dstType));    \
                                                                              \
        return static_cast<dstType>((((x) & 0x00000000000000ffULL) << 56)     \
                                  | (((x) & 0x000000000000ff00ULL) << 40)     \
                                  | (((x) & 0x0000000000ff0000ULL) << 24)     \
                                  | (((x) & 0x00000000ff000000ULL) <<  8)     \
                                  | (((x) & 0x000000ff00000000ULL) >>  8)     \
                                  | (((x) & 0x0000ff0000000000ULL) >> 24)     \
                                  | (((x) & 0x00ff000000000000ULL) >> 40)     \
                                  | (((x) & 0xff00000000000000ULL) >> 56));   \
    }