martinjaeger
commented
3 years ago Wow, thanks a lot for this contribution!
I had the conversion into a pure C library for Zephyr on my ToDo list since a long time already. Really cool.
I'm currently travelling for two weeks, so it might take a few days until I can provide a proper review.
Out of interest: For what sort of application are you using ThingSet and this library?
I was recently thinking about some small changes to the protocol to provide better support for MQTT integration (adding a topic part behind the # of the publication messages). And it was probably not a good idea to allow payload in the GET request in the binary mode, as this can't be translated to CoAP or HTTP. I'll let you know once I have properly documented those issues and ideas for improvement. Which mode are you using? The binary or the text mode?
b0661
Introduction
It would be nice to have a C language interface ThingSet device library to support C only applications.
EDIT: Zephyr module infrastructure will become an extra PR. Commit removed here.
~~As a lot of IoT applications (at least mine !-) are using the Zepyhr RTOS a Zephyr module would ease the library use.~~
Problem description
There is (no known) C language interface ThingSet device library for C only applications. ~~Neither is there Zephyr module support in the ThingSet device library code base.~~
Proposed change
Base the ThingSet device library on a C implementation with a C++ interface shim.
Provide it as a Zephyr moduleProposed change (Detailed)
Move the *.cpp implementation files to C implementations. Keep the functionality, naming, interface mostly the same as the current C++ implementation. Only the interface has to get an additional pointer to the ThingSet object it is working on.
Use the TS/ts_ namespace for the C implementation to avoid name clashes.
Replace printf calls by Zephyr style macros to provide for configurable environment specific logging and error reporting.
Keep the public interface of the C++ ThingSet class the same. Make the class a header only shim that uses the C implementation.
~~Create a zephyr sub-directory to contain all the Zephyr specific module configuration and additional code that is necessary for Zephyr only. Add some libc functions to this code that the Zephyr minimal libc does (currently) not provide to make the library usable without newlib.~~
Dependencies
Existing C++ applications that directly build from source have to use the C implementation files. There are no more *.cpp files.
Concerns and Unresolved Questions
None.
Alternatives
Alternative would be to use the C++ library implementation in C applications. As it is much easier to integrate C into C++ than vice versa this alternative was not regarded.