void parseSignatureFieldText() throws ParseException, CancelledException {
		FunctionSignatureParser parser =
			new FunctionSignatureParser(program.getDataTypeManager(), dataTypeManagerService);
		FunctionDefinitionDataType f = parser.parse(getFunctionSignature(), signatureFieldText);

		// Preserve calling convention and noreturn flag from current model
		f.setNoReturn(functionData.hasNoReturn());
		try {
			f.setCallingConvention(getCallingConventionName());
		}
		catch (InvalidInputException e) {
			// ignore
		}

		setFunctionData(f);
		isInParsingMode = false;
	}
Change custom storage enablement
@param b enablement state
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/FunctionEditorModel.java