Android SDK build scripts

.github/workflows/pull_request.yml

@@ -21,3 +21,141 @@ jobs:
           name: docker-logs
           path: |
             *.log
+
+   static-linux-build:
+     name: Build Static Linux image
+     runs-on: ubuntu-latest
+     steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+      - name: Build Docker images
+        working-directory: swift-ci/sdks/static-linux
+        run: ./build
+
+   android-build:
+     name: Build Android ${{ matrix.arch }} SDK
+     strategy:
+       fail-fast: false
+       matrix:
+         # blank arch builds all (aarch64,x86_64,armv7)
+         #arch: ['']
+         # builds only x86_64 to speed up the validation
+         #arch: ['x86_64']
+         # build both the quick (x86_64) and complete (aarch64,x86_64,armv7) SDKs
+         arch: ['x86_64', '']
+     runs-on: ubuntu-24.04
+     steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+      - name: Install Dependencies
+        run: |
+          sudo apt install -q ninja-build patchelf
+      - name: Build Android SDK
+        working-directory: swift-ci/sdks/android
+        run: |
+          TARGET_ARCHS=${{ matrix.arch }} ./build
+      - name: Get artifact info
+        id: info
+        shell: bash
+        run: |
+          set -ex
+          SWIFT_ROOT=$(dirname ${{ runner.temp }}/swift-android-sdk/host-toolchain/*/usr)
+          echo "swift-root=${SWIFT_ROOT}" >> $GITHUB_OUTPUT
+          echo "swift-path=${SWIFT_ROOT}/usr/bin/swift" >> $GITHUB_OUTPUT
+
+          ARTIFACT_BUILD=$(realpath ${{ runner.temp }}/swift-android-sdk/build/*.artifactbundle)
+          ARTIFACT_PATH=$(realpath ${{ runner.temp }}/swift-android-sdk/products/*.artifactbundle.tar.gz)
+          echo "artifact-path=${ARTIFACT_PATH}" >> $GITHUB_OUTPUT
+          echo "sdk-id=x86_64-unknown-linux-android28" >> $GITHUB_OUTPUT
+
+          ARTIFACT_EXT=".artifactbundle.tar.gz"
+          ARTIFACT_NAME="$(basename ${ARTIFACT_PATH} ${ARTIFACT_EXT})"
+          # artifacts need a unique name so we suffix with the matrix arch(s)
+          if [[ ! -z "${{ matrix.arch }}" ]]; then
+            ARTIFACT_NAME="${ARTIFACT_NAME}-$(echo ${{ matrix.arch }} | tr ',' '-')"
+          fi
+          ARTIFACT_NAME="${ARTIFACT_NAME}${ARTIFACT_EXT}"
+
+          # There is no way to prevent even a single-file artifact from being zipped:
+          # https://github.com/actions/upload-artifact?tab=readme-ov-file#zip-archives
+          # so the actual artifact download will look like:
+          # swift-6.1-RELEASE_android-0.1-x86_64.artifactbundle.tar.gz.zip
+          echo "artifact-name=${ARTIFACT_NAME}" >> $GITHUB_OUTPUT
+
+          # validate some required paths in the artifactbundle
+          pushd ${ARTIFACT_BUILD}/*/*/usr
+            ls lib/swift/android
+            ls lib/swift/android/*
+            ls lib/swift/android/*/swiftrt.o
+            ls lib/*-linux-android/*/crtbegin_dynamic.o
+
+            ls lib/swift_static-*
+            ls lib/swift_static-*/android
+            ls lib/swift_static-*/android/libFoundationEssentials.a
+
+            ls lib/*-linux-android/libFoundationEssentials.so
+            ls lib/*-linux-android/libFoundationNetworking.so
+            ls lib/*-linux-android/libFoundationInternationalization.so
+            ls lib/*-linux-android/lib_FoundationICU.so
+            ls lib/*-linux-android/libFoundationXML.so
+            ls lib/*-linux-android/libTesting.so
+
+            ls lib/swift/clang/lib
+            ls lib/swift/clang/lib/linux
+            ls lib/swift/clang/lib/linux/*/libunwind.a
+          popd
+      - name: Upload SDK artifactbundle
+        uses: actions/upload-artifact@v4
+        with:
+          compression-level: 0
+          name: ${{ steps.info.outputs.artifact-name }}
+          path: ${{ steps.info.outputs.artifact-path }}
+      - name: Cleanup
+        run: |
+          # need to free up some space or else when installing we get: No space left on device
+          rm -rf ${{ runner.temp }}/swift-android-sdk/{build,src}
+      - name: Install artifactbundle
+        shell: bash
+        run: |
+          set -ex
+          ${{ steps.info.outputs.swift-path }} sdk install ${{ steps.info.outputs.artifact-path }}
+          ${{ steps.info.outputs.swift-path }} sdk configure --show-configuration $(${{ steps.info.outputs.swift-path }} sdk list | head -n 1) ${{ steps.info.outputs.sdk-id }}
+          # recent releases require that ANDROID_NDK_ROOT *not* be set
+          # see https://github.com/finagolfin/swift-android-sdk/issues/207
+          echo "ANDROID_NDK_ROOT=" >> $GITHUB_ENV
+
+      - name: Create Demo Project
+        run: |
+          cd ${{ runner.temp }}
+          mkdir DemoProject
+          cd DemoProject
+          ${{ steps.info.outputs.swift-path }} --version
+          ${{ steps.info.outputs.swift-path }} package init
+          echo 'import Foundation' >> Sources/DemoProject/DemoProject.swift
+          echo 'import FoundationEssentials' >> Sources/DemoProject/DemoProject.swift
+          echo 'import FoundationXML' >> Sources/DemoProject/DemoProject.swift
+          echo 'import FoundationNetworking' >> Sources/DemoProject/DemoProject.swift
+          echo 'import Dispatch' >> Sources/DemoProject/DemoProject.swift
+          echo 'import Android' >> Sources/DemoProject/DemoProject.swift
+      - name: Test Demo Project on Android
+        uses: skiptools/swift-android-action@v2
+        with:
+          # only test for the complete arch SDK build to speed up CI
+          run-tests: ${{ matrix.arch == '' }}
+          package-path: ${{ runner.temp }}/DemoProject
+          installed-sdk: ${{ steps.info.outputs.sdk-id }}
+          installed-swift: ${{ steps.info.outputs.swift-root }}
+
+      - name: Checkout swift-algorithms
+        uses: actions/checkout@v4
+        with:
+          repository: apple/swift-algorithms
+          path: swift-algorithms
+      - name: Test swift-algorithms
+        uses: skiptools/swift-android-action@v2
+        with:
+          run-tests: ${{ matrix.arch == '' }}
+          package-path: swift-algorithms
+          installed-sdk: ${{ steps.info.outputs.sdk-id }}
+          installed-swift: ${{ steps.info.outputs.swift-root }}
+

.gitignore

@@ -0,0 +1,2 @@
+.*.swp
+static-swift-linux-sources

swift-ci/sdks/android/README.md

@@ -0,0 +1,43 @@
+# Build scripts for Swift Android SDK
+
+This folder contains scripts to build a Swift Android SDK 
+in the form of an artifactbundle.
+
+## Running
+
+The top-level `./build` script installs a host toolchain and the
+Android NDK, and then invokes `scripts/fetch-source.sh` which will
+fetch tagged sources for libxml2, curl, boringssl, and swift.
+
+It then applies some patches and invokes `scripts/build.sh`,
+which will build the sources for each of the specified
+architectures. Finally, it combines the NDK and the newly built
+SDKs into a single artifactbundle.  
+
+## Specifying Architectures
+
+By default all the supported Android architectures
+(`aarch64`, `x86_64`, `aarmv7`)
+will be built, but this can be reduced in order to speed
+up the build. This can be useful, e.g., as part of a CI that
+validates a pull request, as building a single architecture
+takes around 30 minutes on a standard ubuntu-24.04 GitHub runner,
+whereas building for all the architectures takes over an hour.
+
+To build an artifactbundle for just the `x86_64` architecture, run:
+
+```
+TARGET_ARCHS=x86_64 ./build
+```
+
+## Installing and validating the SDK
+
+The `.github/workflows/pull_request.yml` workflow
+will create and upload an installable SDK named something like:
+`swift-6.1-RELEASE_android-0.1.artifactbundle.tar.gz`
+
+The workflow will also install the SDK locally and use
+[swift-android-action](https://github.com/marketplace/actions/swift-android-action)
+to build and test various Swift packages in an Android emulator.
+
+

swift-ci/sdks/android/build

@@ -0,0 +1,91 @@
+#!/bin/bash -e
+# Swift Android SDK: Top-level Build Script
+
+# default architectures to build for
+TARGET_ARCHS=${TARGET_ARCHS:-aarch64,x86_64,armv7}
+
+ANDROID_NDK_VERSION=android-ndk-r27c
+ANDROID_API=28
+
+SDKROOT=${RUNNER_TEMP:-${TMPDIR:-'/tmp'}}/swift-android-sdk
+mkdir -p ${SDKROOT}
+
+# Install a Swift host toolchain if it isn't already present
+SWIFT_ROOT=${SDKROOT}/host-toolchain
+HOST_OS=ubuntu$(lsb_release -sr)
+SWIFT_VERSION=6.1
+SWIFT_TAG="swift-${SWIFT_VERSION}-RELEASE"
+SWIFT_BRANCH="swift-$(echo $SWIFT_TAG | cut -d- -f2)-release"
+SWIFT_BASE=$SWIFT_TAG-$HOST_OS
+
+if [[ ! -d $SWIFT_ROOT ]]; then
+    mkdir -p $SWIFT_ROOT
+    pushd $SWIFT_ROOT
+
+    SWIFT_URL="https://download.swift.org/$SWIFT_BRANCH/$(echo $HOST_OS | tr -d '.')/$SWIFT_TAG/$SWIFT_BASE.tar.gz"
+    wget -q $SWIFT_URL
+    tar xzf $SWIFT_BASE.tar.gz
+
+    popd
+fi
+
+#HOST_TOOLCHAIN=${HOST_TOOLCHAIN:-$(dirname $(dirname $(which swiftc)))}
+HOST_TOOLCHAIN=$SWIFT_ROOT/$SWIFT_BASE/usr
+$HOST_TOOLCHAIN/bin/swift --version
+
+# ensure the correct Swift is first in the PATH
+export PATH=$HOST_TOOLCHAIN/bin:$PATH
+
+export ANDROID_NDK_HOME=${SDKROOT}/ndk/${ANDROID_NDK_VERSION}
+export ANDROID_NDK=${ANDROID_NDK_HOME}
+
+if [[ ! -d ${ANDROID_NDK_HOME} ]]; then
+    mkdir -p $(dirname ${ANDROID_NDK_HOME})
+    pushd $(dirname ${ANDROID_NDK_HOME})
+    NDKFILE=$(basename $ANDROID_NDK_HOME)-linux.zip
+    wget -q https://dl.google.com/android/repository/${NDKFILE}
+    unzip -q ${NDKFILE}
+    popd
+fi
+
+mkdir -p ${SDKROOT}/products
+
+# Check-out the sources
+if [[ ! -d ${SDKROOT}/src ]]; then
+    scripts/fetch-source.sh --source-dir ${SDKROOT}/src --swift-tag ${SWIFT_TAG}
+fi
+
+# fetch and apply the patches
+PATCHDIR=${SDKROOT}/patches
+if [[ ! -d ${PATCHDIR} ]]; then
+    git clone https://github.com/finagolfin/swift-android-sdk.git ${PATCHDIR}
+
+    # TODO: need to selectively apply patches based on release or not release
+    pushd ${SDKROOT}/src/swift-project
+        echo "Applying patches"
+
+        # patch the patch, which seems to only be needed for an API less than 28 
+        # https://github.com/finagolfin/swift-android-sdk/blob/main/swift-android.patch#L110
+        perl -pi -e 's/#if os\(Windows\)/#if os\(Android\)/g' $PATCHDIR/swift-android.patch
+
+        # remove the need to link in android-execinfo
+        perl -pi -e 's/dispatch android-execinfo/dispatch/g' $PATCHDIR/swift-android.patch
+
+        git apply -v $PATCHDIR/swift-android.patch
+        # swift-android-ci.patch is not needed, since it is only used for llbuild, etc.
+        #git apply -C1 $PATCHDIR/swift-android-ci.patch
+        #git apply -v $PATCHDIR/swift-android-ci-release.patch
+        git apply -v $PATCHDIR/swift-android-testing-release.patch
+
+        perl -pi -e 's%String\(cString: getpass%\"fake\" //%' swiftpm/Sources/PackageRegistryCommand/PackageRegistryCommand+Auth.swift
+        # disable backtrace() for Android (needs either API33+ or libandroid-execinfo, or to manually add in backtrace backport)
+        perl -pi -e 's/os\(Android\)/os\(AndroidDISABLED\)/g' swift-testing/Sources/Testing/SourceAttribution/Backtrace.swift
+
+        # need to un-apply libandroid-spawn since we don't need it for API28+
+        perl -pi -e 's/MATCHES "Android"/MATCHES "AndroidDISABLED"/g' llbuild/lib/llvm/Support/CMakeLists.txt
+        perl -pi -e 's/ STREQUAL Android\)/ STREQUAL AndroidDISABLED\)/g' swift-corelibs-foundation/Sources/Foundation/CMakeLists.txt
+    popd
+fi
+
+./scripts/build.sh --products-dir ${SDKROOT}/products --source-dir ${SDKROOT}/src --build-dir ${SDKROOT}/build --ndk-home ${ANDROID_NDK_HOME} --android-api ${ANDROID_API} --host-toolchain ${HOST_TOOLCHAIN} --archs ${TARGET_ARCHS}
+