/*
 * Copyright 2001-2005, Haiku.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *		Erik Jaesler (erik@cgsoftware.com)
 */

#ifdef USING_MESSAGE4
#	include "MessageUtils4.cpp"
#else

/**	Extra messaging utility functions */

#include <string.h>
#include <ByteOrder.h>

#include <MessageUtils.h>


uint32
_checksum_(const uchar* buf, int32 size)
{
	uint32 sum = 0;
	uint32 temp = 0;

	while (size > 3) {
#if defined(__INTEL__)
		sum += B_SWAP_INT32(*(int*)buf);
#else
		sum += *(int*)buf;
#endif

		buf += 4;
		size -= 4;
	}

	while (size > 0) {
		temp = (temp << 8) + *buf++;
		size -= 1;
	}

	return sum + temp;
}


namespace BPrivate {	// Only putting these here because Be did

status_t
entry_ref_flatten(char* buffer, size_t* size, const entry_ref* ref)
{
	memcpy((void*)buffer, (const void*)&ref->device, sizeof (ref->device));
	buffer += sizeof (ref->device);
	memcpy((void*)buffer, (const void*)&ref->directory, sizeof (ref->directory));
	buffer += sizeof (ref->directory);

	size_t len = 0;
	if (ref->name) {
		len = strlen(ref->name) + 1;	// extra for NULL terminator
		memcpy((void*)buffer, (const void*)ref->name, len);
	}

	*size = sizeof (ref->device) + sizeof (ref->directory) + len;
	return B_OK;
}


status_t
entry_ref_unflatten(entry_ref* ref, const char* buffer, size_t size)
{
	if (size < (sizeof (ref->device) + sizeof (ref->directory))) {
		*ref = entry_ref();
		return B_BAD_VALUE;
	}

	memcpy((void*)&ref->device, (const void*)buffer, sizeof (ref->device));
	buffer += sizeof (ref->device);
	memcpy((void*)&ref->directory, (const void*)buffer,
		   sizeof (ref->directory));
	buffer += sizeof (ref->directory);

	if (ref->device != -1
		&& size > (sizeof (ref->device) + sizeof (ref->directory))) {
		ref->set_name(buffer);
		if (ref->name == NULL) {
			*ref = entry_ref();
			return B_NO_MEMORY;
		}
	} else
		ref->set_name(NULL);

	return B_OK;
}


status_t
entry_ref_swap(char* buffer, size_t size)
{
	if (size < (sizeof (dev_t) + sizeof (ino_t)))
		return B_BAD_DATA;

	dev_t* dev = (dev_t*)buffer;
	*dev = B_SWAP_INT32(*dev);
	buffer += sizeof (dev_t);

	ino_t* ino = (ino_t*)buffer;
	*ino = B_SWAP_INT64(*ino);

	return B_OK;
}


size_t
calc_padding(size_t size, size_t boundary)
{
	size_t pad = size % boundary;
	if (pad)
		pad = boundary - pad;

	return pad;
}

}	// namespace BPrivate


//	#pragma mark -


int32
TChecksumHelper::CheckSum()
{
	 return _checksum_(fBuffer, fBufPtr - fBuffer);
}

#endif	// USING_MESSAGE4