[hexl] Add new port

[WeiDaiWD]

Describe the pull request

• What does your PR fix?

  Added a new port "hexl".

• Which triplets are supported/not supported? Have you updated the CI baseline?

x64 & (windows | linux | osx) & static
No

• Does your PR follow the maintainer guide?

Yes

• If you have added/updated a port: Have you run ./vcpkg x-add-version --all and committed the result?

I ran ./vcpkg x-add-version hexl for this new port only.

[WeiDaiWD]

I'm working on fixing this, in multiple steps:

• hexl downloads a dependency cpu-features. I can add cpu-features as a feature/dependency to hexl by adding a patch to ports/hexl.
• The cpu-features port is wrong. The CpuFeaturesTargets.cmake exports an executable target and checks whether this executable file exists. The file does not exist since vcpkg probably have deleted all executables. Therefore, if cpu-features is installed via vcpkg, find_package(CpuFeatures) will always fail. To fix this, I also need to add a patch to ports/cpu-features.

[WeiDaiWD]

I do need help for one thing. It seems only x64_windows_static and x64_windows_static_md are tested, despite that in ports/hexl/CONTROL I put Supports: x64 & (linux | osx | windows) & static. The correct list of supported triplets are: x64_windows_static, x64_windows_static_md, x64_linux, and x64_osx. What did I miss here?

Much appreciated!

[NancyLi1013]

If we use new functions, vcpkg-cmake and vcpkg-cmake-config should be added to the dependencies.

"dependencies": [
  {
    "name": "vcpkg-cmake",
    "host": true
  },
  {
    "name": "vcpkg-cmake-config",
    "host": true
  }

[NancyLi1013]

Hi @WeiDaiWD
Thanks for adding this new port, I noticed that upstream seems also support dynamic, why do you only support static build in this PR? Can you help make a simple description?

Thanks.

[WeiDaiWD]

I've created a separate PR #18101 to fix port cpu-features. I'll continue on this one once that works.

[NancyLi1013]

This PR should be still in progress. I reopen it. You can merge master to rebuild since PR #18101 has been merged. @WeiDaiWD

[WeiDaiWD]

x64-windows fails because the hexl library does not export its symbols. I added an extra condition in supports in the manifest file.

[WeiDaiWD]

Will do. I've also just noticed that I have to make more changes to the patch, since hexl updated the commit hash for tag 1.1.0.

[NancyLi1013]

LGTM now, thanks for adding this new port. @WeiDaiWD

[strega-nil-ms]

LGTM, thanks @WeiDaiWD :)