Function CVT_move_common

src/common/cvt.cpp:1638–2195

void CVT_move_common(const dsc* from, dsc* to, DecimalStatus decSt, Callbacks* cb)
{
/**************************************
 *
 *      C V T _ m o v e _ c o m m o n
 *
 **************************************
 *
 * Functional description
 *      Move (and possible convert) something to something else.
 *
 **************************************/
	ULONG length = from->dsc_length;
	UCHAR* p = to->dsc_address;
	const UCHAR* q = from->dsc_address;

	// If the datatypes and lengths are identical, just move the
	// stuff byte by byte.  Although this may seem slower than
	// optimal, it would cost more to find the fast move than the
	// fast move would gain.

	if (DSC_EQUIV(from, to, false))
	{
		if (length) {
			memcpy(p, q, length);
		}
		return;
	}

	// Special optimization case: RDB$DB_KEY is binary compatible with CHAR(8) OCTETS

	if ((from->dsc_dtype == dtype_text &&
		 to->dsc_dtype == dtype_dbkey &&
		 from->dsc_ttype() == ttype_binary &&
		 from->dsc_length == to->dsc_length) ||
		(to->dsc_dtype == dtype_text &&
		 from->dsc_dtype == dtype_dbkey &&
		 to->dsc_ttype() == ttype_binary &&
		 from->dsc_length == to->dsc_length))
	{
		memcpy(p, q, length);
		return;
	}

	// Do data type by data type conversions.  Not all are supported,
	// and some will drop out for additional handling.

	dsc d;
	switch (to->dsc_dtype)
	{
	case dtype_timestamp:
		switch (from->dsc_dtype)
		{
		case dtype_varying:
		case dtype_cstring:
		case dtype_text:
			{
				ISC_TIMESTAMP_TZ date;