How to tell FetchContent to keep archive directory structure

Code
1

Hello,

I am downloading some header files from a remote URL and unzipping them using FetchContent. This works as expected, except for the fact that the zip files directory structure isn’t being kept the same.

For example, if I take a look at the zip file I am downloading in 7zip, the directory structure looks like this:

- foo/
  - bar/
    - example.h

But when using FetchContent like so:

FetchContent_Declare(
  package_headers
  URL ${header_url}
)
FetchContent_MakeAvailable(package_headers)

The directory structure ends up like this

- build/
  - desktop_debug_shared
    - _deps
      - package_headers-src
        - bar/
          - example.h

This only seems to happen if the zip has only a folder in the top level dir and nothing else.

I would like to keep the top-level folder to keep the include path the same.

Any help is appreciated!

2

The code that implements that behavior is in extractfile.cmake.in. There’s currently no option to prevent it from discarding a single top level directory. As a workaround, you can use the DOWNLOAD_NO_EXTRACT option to prevent extraction and then perform extraction manually yourself. I acknowledge that’s not ideal, but it is a workaround available to you since CMake 3.6.

3

Thank you for tracking this behavior. I appreciate the workaround!