如何用C中的通用代码实现可执行文件和共享库

Question

I'm designing a Linux C project which is composed by two binaries: an executable and a shared library.

I have the following project structure using Eclipse-cdt:

    +-----folderA
        ------------- sourceA.c
        ------------- sourceA.h
    +-----folderB
        ------------- sourceB.c
        ------------- sourceB.h
    main.c


    +-----folderB
        ------------- libcode.c
        ------------- libcode.h

The Shared Library code in libcode.c is strictly dependent on folderA and folderB code from the Main Project.

How could I organize the projects in order to have no duplicated files?

Solution A (Current)

The best solution I've found so far, is to use linked resources inside eclipse:

    +-----folderA
        ------------- sourceA.c
        ------------- sourceA.h
    +-----folderB
        ------------- sourceB.c
        ------------- sourceB.h
        
        
    main.c


    +-----folderA 
        ------------- sourceA.c 
        ------------- sourceA.h 
    +-----folderB 
        ------------- sourceB.c 
        ------------- sourceB.h 
        ------------- libcode.c 
        ------------- libcode.h 

Notice that I moved 100% of shared library code into the main project and linked all the files I needed in the Shared Library. This way I don't need to have any "physical" source files inside the Shared Library Project, but I still think it's not a good idea, because it can surprise other developers (violating POLS principle).

Solution B

There is the option to move all the common code into a third project and make the two projects depend on it, but in my case it will lead into a big code refactoring, which I would like to avoid.

Any other possibility? Is the solution B definetly a better practice?

Answer 1

You should probably put the source in folderA and folderB into your shared library since they apparently contain core functionality. In your executable put the source that uses the library to do something, for example, calling various functions in libcode to achieve some goal for the end user. You will need to link the executable to the shared library.

Main Project Executable [links to shared library] 
    main.c              [uses libcode to do stuff]

Shared Library Project
    +-----folderA
        ------------- sourceA.c
        ------------- sourceA.h
    +-----folderB
        ------------- sourceB.c
        ------------- sourceB.h
        ------------- libcode.c
        ------------- libcode.h