Tunnel Grammar Studio (TGS) is described as 'Tunnel Grammar Studio is an Integrated Development Environment for generating parsers (also known as parser generator or a compiler compiler). It is used to develop stand alone Parsing Machines from given ABNF syntax grammar'. There are 2 alternatives to Tunnel Grammar Studio (TGS) for Linux, Mac and Windows. The best alternative is ANTLR, which is both free and Open Source.
ANTLR, ANother Tool for Language Recognition, is a language tool that provides a framework for constructing recognizers, interpreters, compilers, and translators from grammatical descriptions containing actions in a variety of target languages.
textX is a meta-language for building Domain-Specific Languages (DSLs) in Python. It is inspired by Xtext. It will help you build your textual language easily. You can invent your own language or build a support for an existing textual language.