NAME

AG_ByteSwap — agar byte swapping macros

SYNOPSIS

#include <agar/core/byteswap.h>

DESCRIPTION

These macros swap the order of bytes in integers and floating-point types. They are useful when reading or writing data of a specific endianness.

Uint16
AG_Swap16(Uint16 value);

Uint32
AG_Swap32(Uint32 value);

Uint64
AG_Swap64(Uint64 value);

Uint16
AG_SwapLE16(Uint16 value);

Uint32
AG_SwapLE32(Uint32 value);

Uint64
AG_SwapLE64(Uint64 value);

Uint16
AG_SwapBE16(Uint16 value);

Uint32
AG_SwapBE32(Uint32 value);

Uint64
AG_SwapBE64(Uint64 value);

The AG_Swap16(), AG_Swap32() and AG_Swap64() functions return the parameter's value with the byte order reversed.

AG_SwapLE16(), AG_SwapLE32(), and AG_SwapLE64() return the given value with the byte order reversed if the current architecture is big-endian. On little-endian machines, these functions return the value unchanged.

AG_SwapBE16(), AG_SwapBE32() and AG_SwapBE64() return the given value with the byte order reversed if the current architecture is little-endian. On big-endian machines, these functions return the value unchanged.

If 64-bit types are not supported (!AG_HAVE_64BIT), then AG_Swap64(), AG_SwapLE64() and AG_SwapBE64() are undefined.

EXAMPLES

The following code reverses the byte order of an array of 32-bit values:

void
SwapData32(Uint32 *data, int len)
{
	int i;

	for (i = 0; i < len; i++)
		data[i] = AG_Swap32(data[i]);
}

SEE ALSO

AG_DataSource(3), AG_Intro(3)

HISTORY

The AG_ByteSwap macros first appeared in Agar 1.3.4.