GNU radio offers an extended library of signal processing modules that are necessary for developing, testing, and evaluating PHY- and MAC-layer communication protocols, but support is also provided for network- and transport-layer protocols. Testing, evaluating, and troubleshooting communication protocols used in wireless communication systems is challenging. The results of many studies on this topic (see Section 2) have shown that effective automation of test suites, generating appropriate traffic, considering timing constraints, real-time handling of monitoring data, and storage and visualization/analysis of gathered data are some of the main issues related to testing these protocols. Many papers have presented various testing platforms adapted to specific protocols and scenarios like military or industrial communication systems. This paper proposes a generic software testing platform (testbed) for wireless communication protocols developed in GNU radio. The proposed platform provides a solution for isolating the application under test and feeding the application with any data traffic controlled by IP or Ethernet protocols, the types of traffic used in most real-life scenarios. This feature makes it interoperable with other traffic generators and network analysis tools, which is convenient for generating different user data flows. The proposed testing platform is designed in such a way to efficiently collect, store, and analyze large amounts of real-time data. These features are essential for testing physical-layer protocols. They enable various testing operations such as functional testing, conformance testing, quality evaluation testing, and comprehensive dynamic testing. The platform can perform the mentioned tests in simulated and real-life conditions when SDR interfaces are used for communication. The entire setup and management of the testbed are implemented in Python, which means they can be easily integrate into an automation testing framework. Additionally, the platform allows dynamic reconfiguration of the application under testing through JSON (JavaScript Object Notation) objects if its implementation supports it. In summary, this paper's contributions are the architecture and the design of a generic, practical, flexible, and scalable testing platform (testbed) for GNU radio applications that allows for the integration of various software and networking tools necessary to test and evaluate time-constrained complex signal processing applications. In addition, this paper proposes and analyzes several efficient methods to build, serialize, and parse monitoring messages from GNU radio applications. The structure of this paper is as follows: Section 2 presents a short review of the technical literature related to software testing classification and principles, relating to specific issues raised by testing communication protocols, in general, and by testing wireless communication protocols, in particular. Section 3 presents in detail the proposed software testing platform, the architecture of the systems, the networking environments proposed for sending test data to the GNU radio application under test, and the real-time monitoring data acquisition and handling solutions. Section 4 presents our experimental results and a discussion of these results, and Section 5 concludes this paper.