Fixed #9086: Firebird 6.0.0 error "Data type unknown" running udf which returns string using returns parameter <n> - patch from Dimitry Sibiryakov <sd@ibphoenix.com>

Author: AlexPeshkoff

src/common/dsc.cpp

@@ -1713,6 +1713,12 @@ void dsc::getSqlInfo(SLONG* sqlLength, SLONG* sqlSubType, SLONG* sqlScale, SLONG
 			*sqlScale = dsc_scale;
 			break;
 
+		case dtype_cstring:
+			*sqlType = SQL_VARYING;
+			*sqlLength -= 1; // Zero-terminator
+			*sqlSubType = dsc_sub_type;
+			break;
+
 		case dtype_varying:
 			*sqlType = SQL_VARYING;
 			*sqlLength -= sizeof(USHORT);

src/dsql/gen.cpp

@@ -345,6 +345,20 @@ void GEN_descriptor( DsqlCompilerScratch* dsqlScratch, const dsc* desc, bool tex
 		dsqlScratch->appendUShort(desc->dsc_length);
 		break;
 
+	case dtype_cstring:
+		if (texttype || desc->getTextType() == ttype_binary || desc->getTextType() == ttype_none)
+		{
+			dsqlScratch->appendUChar(blr_varying2);
+			dsqlScratch->appendUShort(desc->getTextType());
+		}
+		else
+		{
+			dsqlScratch->appendUChar(blr_varying2);	// automatic transliteration
+			dsqlScratch->appendUShort(ttype_dynamic);
+		}
+		dsqlScratch->appendUShort(desc->dsc_length - 1);
+		break;
+
 	case dtype_varying:
 		if (texttype || desc->getTextType() == ttype_binary || desc->getTextType() == ttype_none)
 		{