Function INTL_convert_string

src/jrd/intl.cpp:781–901

void INTL_convert_string(dsc* to, const dsc* from, Firebird::Callbacks* cb)
{
/**************************************
 *
 *      I N T L _ c o n v e r t _ s t r i n g
 *
 **************************************
 *
 * Functional description
 *      Convert a string from one type to another
 *
 **************************************/

	const auto tdbb = JRD_get_thread_data();

	fb_assert(to != NULL);
	fb_assert(from != NULL);
	fb_assert(IS_TEXT(to) && IS_TEXT(from));

	const CHARSET_ID from_cs = INTL_charset(tdbb, INTL_TTYPE(from));
	const CHARSET_ID to_cs = INTL_charset(tdbb, INTL_TTYPE(to));

	UCHAR* p = to->dsc_address;

	// Must convert dtype(cstring,text,vary) and ttype(ascii,binary,..intl..)

	UCHAR* from_ptr;
	USHORT from_type;
	const USHORT from_len = CVT_get_string_ptr(from, &from_type, &from_ptr, NULL, 0,
		tdbb->getAttachment()->att_dec_status, cb->err);

	const ULONG to_size = TEXT_LEN(to);

	const UCHAR* q = from_ptr;
	CharSet* const toCharSet = INTL_charset_lookup(tdbb, to_cs);

	UCHAR* const to_ptr = to->dsc_dtype == dtype_varying ?
		reinterpret_cast<UCHAR*>(((vary*) p)->vary_string) :
		p;

	ULONG to_fill;

	if (from_cs != to_cs && to_cs != CS_BINARY && to_cs != CS_NONE && from_cs != CS_NONE)
	{
		ULONG to_len;

		try
		{
			to_len = INTL_convert_bytes(tdbb, to_cs, to_ptr, to_size, from_cs, from_ptr, from_len, cb->err);
		}
		catch (const status_exception& e)
		{
			const auto status = e.value();

			if (status[0] == isc_arg_gds &&
				status[1] == isc_arith_except &&
				status[2] == isc_arg_gds &&
				status[3] == isc_string_truncation &&