[curl] Fix android builds. Greatly simplify pkgconfig handling.

[ras0219]

Includes changes from #17400. Tested using docker.io/menny/android_ndk:1.15.1.

https://github.com/menny/docker_android/tree/master/android_ndk
https://hub.docker.com/r/menny/android_ndk

$ docker pull menny/android_ndk:1.15.1

After launching the container, do:

export ANDROID_NDK_HOME=$ANDROID_HOME/ndk/22.0.7026061
git clone https://github.com/ras0219/vcpkg -b dev/roschuma/curl-android
cd vcpkg
./bootstrap-vcpkg.sh
echo "
set(VCPKG_TARGET_ARCHITECTURE arm)
set(VCPKG_CRT_LINKAGE dynamic)
set(VCPKG_LIBRARY_LINKAGE static)
set(VCPKG_CMAKE_SYSTEM_NAME Android)
" > triplets/community/arm-android.cmake
echo "
set(VCPKG_TARGET_ARCHITECTURE arm)
set(VCPKG_CRT_LINKAGE dynamic)
set(VCPKG_LIBRARY_LINKAGE dynamic)
set(VCPKG_CMAKE_SYSTEM_NAME Android)
" > triplets/community/arm-android-dynamic.cmake
./vcpkg install aws-sdk-cpp[core]:arm-android aws-sdk-cpp[core]:arm-android-dynamic --no-binarycaching

• What does your PR fix?

  Fixes [curl] Fix usage of curl library on Android. #17400

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

  <all / linux, windows, ...>, <Yes/No>

• Does your PR follow the maintainer guide?

  Your answer

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

  <Yes / I am still working on this PR>

If you are still working on the PR, open it as a Draft: https://github.blog/2019-02-14-introducing-draft-pull-requests/

[ahmedyarub]

Tested on Windows and worked like a charm!

[talregev]

@ras0219 Hi Robert, your fix is working with pkg-config when we compile for android with libcurl.
curl-config is showing permission denied and may have the wrong flags.
We now switch to pkg-config compilation with vcpkg.
Thank you for this fix

[dg0yt]

curl-config is showing permission denied and may have the wrong flags.

The port file could set permissions with file(INSTALL ...).
IMO curl-config should go the the tools folder. It will be used by by build scripts on the host, not the target. (Example: gdal).

[talregev]

@dg0yt
Before the fix (current state of vcpkg) curl-config it didn't show permission denied. After the fix it is showing permission denied.
curl-config is also may give the wrong flags for libcurl compilation for android.
Also curl-config will not be relevant for us because we switching to compile libcurl vcpkg with android with pkg-config, as you can see on my PR that I mention this PR.

[dg0yt]

Also curl-config will not relevant for us because we switching to compile libcurl vcpkg with android with pkg-config

I think it is relevant for fixing #9068 (GDAL on Linux), at least if using gdal configuration parameters.

[talregev]

I think it is relevant for fixing #9068 (GDAL on Linux), at least if using gdal configuration parameters.

I knew that it might be relevant for other projects, so that why I also report about curl-config

[ras0219-msft]

I found the issue -- I was trying to replace prefix=/absolute/path with prefix=$(get current script path), but messed up the replacement and just wrote back out $(get current script path).

With this, the PR is good to go on my side assuming it passes CI. @talregev I'd appreciate it if you wouldn't mind trying your previous code (using curl-config) on this new version, as some validation that the new curl-config works outside my machine.

[talregev]

@ras0219 Good morning Robert. It is not my code, it is opensource code.
And sure. I am testing both curl-config and pkg-config with this PR.
Thank you.

[talregev]

@ras0219 Hi Robert, I open a two test branches as you can see. (I mention this PR on these branches).
All our tests are successful on both branches. For us the curl-config and pkg-config are good in this PR.
Thank you again for your time and this fix.

[JackBoosY]

Please bump the port version. See documentation.
Also please run command vcpkg x-add-version --all then commit the changes.

[dg0yt]

@ras0219 Once again regarding curl-config: It is meant to be executed as a shell script. I would prefer to find this installed with executable bits set, and probably it belongs to /tools/ in this case. (I'm trying to use it for the gdal port on Unix. It gets harder when it is not executable. Gdal also wants geos-config which would be executable but is deleted...)

[talregev]

@ras0219 @ras0219-msft @JackBoosY any news?

[ras0219-msft]

I hadn't incremented the version number, so it failed CI. If this passes, it's good to merge.

[dg0yt]

Can you have another look at the curl pc files? On x64-linux, with the curl from master I see a duplication of 'Libs'.

...
Libs: -L"${libdir}" -lcurl-d  -lgcc -lgcc_s -lc -lgcc -lgcc_s -ldl -lpthread -lssl -lcrypto -lz  -lgcc -lgcc_s -lc -lgcc -lgcc_s -ldl -lpthread -lssl -lcrypto -lz

In the buildtree, it looks a little bit different:

Libs: -L${libdir} -lcurl-d  -lgcc -lgcc_s -lc -lgcc -lgcc_s -ldl -lpthread -lssl -lcrypto -lz
Libs.private:  -lgcc -lgcc_s -lc -lgcc -lgcc_s -ldl -lpthread -lssl -lcrypto -lz

[Neumann-A]

@dg0yt vcpkg_fixup_pkgconfig merges Libs.private into Libs if VCPKG_LIBRARY_LINKAGE is static

[dg0yt]

@dg0yt vcpkg_fixup_pkgconfig merges Libs.private into Libs if VCPKG_LIBRARY_LINKAGE is static

@Neumann-A Yes, garbage-in-garbage-out here. I want to ask if there could be an improvement on the input side (port curl).

[ras0219-msft]

I'm going to merge this PR as-is for now and look at improving the .pc in a followup. Thanks everyone!

[dg0yt]

👍
@ras0219-msft I'm fighting with looking at various pc files (towards fixing gdal for Unix). Cf. #17748 for a general approach to the duplication issue.