Add android port

.bazelrc

@@ -81,3 +81,45 @@ build:libc++ --action_env=BAZEL_CXXOPTS=-stdlib=libc++
 build:libc++ --action_env=BAZEL_LINKLIBS=-l%:libc++.a:-l%:libc++abi.a
 build:libc++ --action_env=BAZEL_LINKOPTS=-lm:-pthread
 build:libc++ --define force_libcpp=enabled
+
+# Android NDK Toolchain Configurations
+# Prerequisites:
+#   1. Install Android NDK (r25b or later)
+#   2. Set ANDROID_NDK_HOME to the NDK installation path
+#   3. Add to MODULE.bazel (see bazel/android/ndk.MODULE.bazel):
+#        android_ndk_repository_extension = use_extension(...)
+#        use_repo(android_ndk_repository_extension, "androidndk")
+#        register_toolchains("@androidndk//:all")
+build:android_arm64 --platforms=//platform/android:android_arm64
+build:android_arm64 --action_env=ANDROID_NDK_HOME
+build:android_arm64 --cxxopt=-D__ANDROID_API__=28
+build:android_arm64 --cpu=aarch64
+build:android_arm64 --linkopt=-lc++_static
+build:android_arm64 --linkopt=-lc++abi
+build:android_arm64 --extra_toolchains=@androidndk//:all
+
+build:android_x86_64 --platforms=//platform/android:android_x86_64
+build:android_x86_64 --action_env=ANDROID_NDK_HOME
+build:android_x86_64 --cxxopt=-D__ANDROID_API__=28
+build:android_x86_64 --cpu=x86_64
+build:android_x86_64 --linkopt=-lc++_static
+build:android_x86_64 --linkopt=-lc++abi
+build:android_x86_64 --extra_toolchains=@androidndk//:all
+
+build:android --config=android_arm64
+
+# QNX 8 Toolchain Configurations
+# Set QNX_SDP_PATH environment variable or use default ~/qnx800
+build:qnx_aarch64 --platforms=//bazel/toolchains/qnx/platforms:qnx_aarch64
+build:qnx_aarch64 --action_env=QNX_SDP_PATH
+build:qnx_aarch64 --define=QNX_SDP_PATH=/home/dave.allison/qnx800
+build:qnx_aarch64 --cxxopt=-D__QNX__
+
+build:qnx_x86_64 --platforms=//bazel/toolchains/qnx/platforms:qnx_x86_64
+build:qnx_x86_64 --action_env=QNX_SDP_PATH
+build:qnx_x86_64 --define=QNX_SDP_PATH=/home/dave.allison/qnx800
+build:qnx_x86_64 --cxxopt=-D__QNX__
+
+# QNX common flags
+build:qnx --cxxopt=-std=c++17
+build:qnx --cxxopt=-Wno-sign-compare

.github/scripts/android-test.sh

@@ -0,0 +1,72 @@
+#!/bin/bash
+set -euo pipefail
+
+# Wait for device to be fully available after emulator boot
+adb wait-for-device
+adb root
+sleep 5
+adb wait-for-device
+adb shell "while [[ -z \$(getprop sys.boot_completed) ]]; do sleep 1; done"
+
+# Create shared memory directory
+adb shell "mkdir -p /dev/subspace && chmod 777 /dev/subspace"
+adb shell "mkdir -p /data/local/tmp"
+
+# Collect shared libraries (dereference symlinks from bazel output)
+mkdir -p /tmp/android_libs
+find bazel-bin/ -name "*.so" -path "*_solib*" -exec cp -L {} /tmp/android_libs/ \; 2>/dev/null || true
+find bazel-bin/plugins/ -name "*.so" -exec cp -L {} /tmp/android_libs/ \; 2>/dev/null || true
+
+if ls /tmp/android_libs/*.so 1>/dev/null 2>&1; then
+  adb push /tmp/android_libs /data/local/tmp/android_libs
+fi
+
+LIB="LD_LIBRARY_PATH=/data/local/tmp/android_libs"
+
+# Push test binaries
+adb push bazel-bin/server/subspace_server /data/local/tmp/subspace_server
+adb push bazel-bin/client/client_test /data/local/tmp/client_test
+adb push bazel-bin/client/bridge_test /data/local/tmp/bridge_test
+adb push bazel-bin/common/split_buffer_test /data/local/tmp/split_buffer_test
+adb push bazel-bin/coro_rpc/test/rpc_test /data/local/tmp/coro_rpc_test
+adb push bazel-bin/coro_rpc/server/server_test /data/local/tmp/coro_rpc_server_test
+adb push bazel-bin/coro_rpc/client/client_test /data/local/tmp/coro_rpc_client_test
+adb push bazel-bin/co20_rpc/test/rpc_test /data/local/tmp/co20_rpc_test
+adb push bazel-bin/co20_rpc/server/server_test /data/local/tmp/co20_rpc_server_test
+adb push bazel-bin/co20_rpc/client/client_test /data/local/tmp/co20_rpc_client_test
+adb push bazel-bin/asio_rpc/test/rpc_test /data/local/tmp/asio_rpc_test
+adb push bazel-bin/asio_rpc/server/server_test /data/local/tmp/asio_rpc_server_test
+adb push bazel-bin/asio_rpc/client/client_test /data/local/tmp/asio_rpc_client_test
+
+# Push plugin .so files to relative path expected by tests
+adb shell "mkdir -p /data/local/tmp/plugins"
+find bazel-bin/plugins/ -name "*.so" -exec adb push {} /data/local/tmp/plugins/ \; 2>/dev/null || true
+
+# Make binaries executable
+adb shell "chmod +x /data/local/tmp/*_test /data/local/tmp/subspace_server"
+
+echo "=== split_buffer_test ==="
+adb shell "cd /data/local/tmp && $LIB ./split_buffer_test"
+
+echo "=== client_test ==="
+adb shell "cd /data/local/tmp && $LIB ./client_test"
+
+echo "=== bridge_test ==="
+adb shell "cd /data/local/tmp && $LIB ./bridge_test"
+
+echo "=== coro_rpc tests ==="
+adb shell "cd /data/local/tmp && $LIB ./coro_rpc_test"
+adb shell "cd /data/local/tmp && $LIB ./coro_rpc_server_test"
+adb shell "cd /data/local/tmp && $LIB ./coro_rpc_client_test"
+
+echo "=== co20_rpc tests ==="
+adb shell "cd /data/local/tmp && $LIB ./co20_rpc_test"
+adb shell "cd /data/local/tmp && $LIB ./co20_rpc_server_test"
+adb shell "cd /data/local/tmp && $LIB ./co20_rpc_client_test"
+
+echo "=== asio_rpc tests ==="
+adb shell "cd /data/local/tmp && $LIB ./asio_rpc_test"
+adb shell "cd /data/local/tmp && $LIB ./asio_rpc_server_test"
+adb shell "cd /data/local/tmp && $LIB ./asio_rpc_client_test"
+
+echo "=== All Android tests passed ==="

.github/scripts/cmake-android-test.sh

@@ -0,0 +1,56 @@
+#!/bin/bash
+set -euo pipefail
+
+BUILD_DIR="build/android"
+
+# Wait for device to be fully available after emulator boot
+adb wait-for-device
+adb root
+sleep 5
+adb wait-for-device
+adb shell "while [[ -z \$(getprop sys.boot_completed) ]]; do sleep 1; done"
+
+# Create shared memory directory
+adb shell "mkdir -p /dev/subspace && chmod 777 /dev/subspace"
+adb shell "mkdir -p /data/local/tmp"
+
+# Push libc++_shared.so from NDK (needed since we built with ANDROID_STL=c++_shared)
+NDK_LIBCXX=$(find "$ANDROID_NDK_HOME" -name "libc++_shared.so" -path "*/x86_64-linux-android/*" | head -1)
+if [ -n "$NDK_LIBCXX" ]; then
+  adb push "$NDK_LIBCXX" /data/local/tmp/libc++_shared.so
+fi
+
+LIB="LD_LIBRARY_PATH=/data/local/tmp:/data/local/tmp/plugins"
+
+# Push test binaries
+adb push "$BUILD_DIR/server/subspace_server" /data/local/tmp/subspace_server
+adb push "$BUILD_DIR/client/client_test" /data/local/tmp/client_test
+adb push "$BUILD_DIR/common/split_buffer_test" /data/local/tmp/split_buffer_test
+adb push "$BUILD_DIR/common/common_test" /data/local/tmp/common_test
+adb push "$BUILD_DIR/c_client/c_client_test" /data/local/tmp/c_client_test
+adb push "$BUILD_DIR/shadow/shadow_test" /data/local/tmp/shadow_test
+
+# Push plugin .so files
+adb shell "mkdir -p /data/local/tmp/plugins"
+adb push "$BUILD_DIR/plugins/nop_plugin.so" /data/local/tmp/plugins/
+adb push "$BUILD_DIR/plugins/split_buffer_free_test_plugin.so" /data/local/tmp/plugins/
+
+# Make binaries executable
+adb shell "chmod +x /data/local/tmp/*_test /data/local/tmp/subspace_server"
+
+echo "=== common_test ==="
+adb shell "cd /data/local/tmp && $LIB ./common_test"
+
+echo "=== split_buffer_test ==="
+adb shell "cd /data/local/tmp && $LIB ./split_buffer_test"
+
+echo "=== client_test ==="
+adb shell "cd /data/local/tmp && $LIB ./client_test"
+
+echo "=== c_client_test ==="
+adb shell "cd /data/local/tmp && $LIB ./c_client_test"
+
+echo "=== shadow_test ==="
+adb shell "cd /data/local/tmp && $LIB ./shadow_test"
+
+echo "=== All CMake Android tests passed ==="

.github/workflows/ci.yml

@@ -256,3 +256,110 @@ jobs:
 
       - name: Run CMake tests
         run: ctest --test-dir build/cmake-${{ matrix.build_type }} --output-on-failure
+
+  cmake-android:
+    name: cmake-android (x86_64)
+    runs-on: ubuntu-latest
+    timeout-minutes: 45
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Set up Android NDK
+        run: echo "ANDROID_NDK_HOME=$ANDROID_NDK_LATEST_HOME" >> $GITHUB_ENV
+
+      - name: Configure CMake for Android x86_64
+        run: |
+          cmake -S . -B build/android \
+            -DCMAKE_TOOLCHAIN_FILE=$ANDROID_NDK_HOME/build/cmake/android.toolchain.cmake \
+            -DANDROID_ABI=x86_64 \
+            -DANDROID_PLATFORM=android-28 \
+            -DANDROID_STL=c++_shared \
+            -DCMAKE_BUILD_TYPE=Release
+
+      - name: Build
+        run: cmake --build build/android --parallel $(nproc)
+
+      - name: Enable KVM
+        run: |
+          echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' | sudo tee /etc/udev/rules.d/99-kvm4all.rules
+          sudo udevadm control --reload-rules
+          sudo udevadm trigger --name-match=kvm
+
+      - name: Run tests on Android emulator
+        uses: reactivecircus/android-emulator-runner@v2
+        with:
+          api-level: 30
+          target: google_apis
+          arch: x86_64
+          emulator-options: -no-snapshot-save -no-window -gpu swiftshader_indirect -noaudio -no-boot-anim -camera-back none
+          emulator-boot-timeout: 900
+          script: bash .github/scripts/cmake-android-test.sh
+
+  android:
+    name: android (x86_64)
+    runs-on: ubuntu-latest
+    timeout-minutes: 45
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Install Bazel
+        uses: bazel-contrib/setup-bazel@0.18.0
+        with:
+          bazelisk-cache: true
+          disk-cache: ${{ github.workflow }}-android
+          repository-cache: true
+
+      - name: Set up Android NDK
+        run: |
+          ANDROID_SDK_ROOT="${ANDROID_HOME:-/usr/local/lib/android/sdk}"
+          # Find the installed NDK version
+          NDK_VERSION=$(ls "$ANDROID_SDK_ROOT/ndk" | sort -V | tail -1)
+          echo "ANDROID_NDK_HOME=$ANDROID_SDK_ROOT/ndk/$NDK_VERSION" >> "$GITHUB_ENV"
+
+      - name: Cross-compile for Android x86_64
+        run: |
+          bazel build \
+            //server:subspace_server \
+            //client:client_test \
+            //client:bridge_test \
+            //common:split_buffer_test \
+            //plugins:nop_plugin.so \
+            //plugins:split_buffer_free_test_plugin.so \
+            //coro_rpc/test:rpc_test \
+            //coro_rpc/server:server_test \
+            //coro_rpc/client:client_test \
+            //co20_rpc/test:rpc_test \
+            //co20_rpc/server:server_test \
+            //co20_rpc/client:client_test \
+            //asio_rpc/test:rpc_test \
+            //asio_rpc/server:server_test \
+            //asio_rpc/client:client_test \
+            --verbose_failures \
+            --config=android_x86_64
+
+      - name: Enable KVM
+        run: |
+          echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' | sudo tee /etc/udev/rules.d/99-kvm4all.rules
+          sudo udevadm control --reload-rules
+          sudo udevadm trigger --name-match=kvm
+
+      - name: Run tests on Android emulator
+        uses: reactivecircus/android-emulator-runner@v2
+        with:
+          api-level: 30
+          target: google_apis
+          arch: x86_64
+          emulator-options: -no-snapshot-save -no-window -gpu swiftshader_indirect -noaudio -no-boot-anim -camera-back none
+          emulator-boot-timeout: 900
+          script: bash .github/scripts/android-test.sh
+
+      - name: Upload Android test logs
+        uses: actions/upload-artifact@v7
+        if: failure()
+        with:
+          name: android-test-logs
+          path: bazel-testlogs

Android.bp

@@ -0,0 +1,23 @@
+// Copyright 2023-2026 David Allison
+// All Rights Reserved
+// See LICENSE file for licensing information.
+
+// Common defaults for all subspace native modules.
+cc_defaults {
+    name: "subspace_defaults",
+    cflags: [
+        "-std=c++17",
+        "-Wall",
+        "-Wextra",
+        "-Wno-missing-field-initializers",
+        "-Wno-unused-parameter",
+    ],
+    target: {
+        android: {
+            cflags: ["-DSUBSPACE_ANDROID"],
+        },
+    },
+    local_include_dirs: ["."],
+    stl: "c++_shared",
+    min_sdk_version: "28",
+}

BUILD.bazel

@@ -2,16 +2,29 @@ package(default_visibility = ["//visibility:public"])
 
 config_setting(
   name = "macos_arm64",
-  values = {"cpu": "darwin_arm64"},
+  constraint_values = [
+      "@platforms//os:macos",
+      "@platforms//cpu:aarch64",
+  ],
 )
 
 config_setting(
   name = "macos_default",
-  values = {"cpu": "darwin"},
+  constraint_values = [
+      "@platforms//os:macos",
+  ],
 )
 
 config_setting(
   name = "macos_x86_64",
-  values = {"cpu": "darwin_x86_64"},
+  constraint_values = [
+      "@platforms//os:macos",
+      "@platforms//cpu:x86_64",
+  ],
+)
+
+config_setting(
+  name = "android",
+  constraint_values = ["@platforms//os:android"],
 )
 

CMakeLists.txt

@@ -18,10 +18,20 @@ set(ABSL_BUILD_TEST_HELPERS ON CACHE INTERNAL "Enable Abseil TESTONLY+PUBLIC hel
 set(ABSL_USE_EXTERNAL_GOOGLETEST ON CACHE INTERNAL "Use our GoogleTest instead of Abseil downloading its own")
 set(ABSL_FIND_GOOGLETEST OFF CACHE INTERNAL "Don't find_package(GTest); we provide it via FetchContent")
 
+# When cross-compiling, don't build protoc (we use a host-native one).
+if(CMAKE_CROSSCOMPILING)
+    set(protobuf_BUILD_PROTOC_BINARIES OFF CACHE INTERNAL "Skip building protoc for target")
+endif()
+
 # Add common compile options as found in subspace/BUILD
 # These will apply to all targets in this CMakeLists.txt unless overridden.
 add_compile_options(-Wall -Wextra -Wno-missing-field-initializers -Wno-unused-parameter)
 
+# --- Android-specific settings ---
+if(ANDROID)
+    add_compile_definitions(SUBSPACE_ANDROID)
+endif()
+
 # --- Apple Silicon (ARM64) specific settings ---
 # Ensure that CMake targets the correct architecture when building on Apple platforms.
 # This value will be propagated to sub-dependencies.
@@ -97,11 +107,10 @@ FetchContent_Declare(
     protobuf
     GIT_REPOSITORY https://github.com/protocolbuffers/protobuf.git
     GIT_TAG v29.5
-    # Protobuf's CMake build can be configured to build only necessary components
     CMAKE_ARGS
-        -Dprotobuf_BUILD_TESTS=OFF # Explicitly disable building tests to avoid gmock conflicts
+        -Dprotobuf_BUILD_TESTS=OFF
         -Dprotobuf_BUILD_EXAMPLES=OFF
-        -Dprotobuf_BUILD_SHARED_LIBS=OFF # Build static libs
+        -Dprotobuf_BUILD_SHARED_LIBS=OFF
         -DCMAKE_OSX_ARCHITECTURES="${CMAKE_OSX_ARCHITECTURES}"
 )
 FetchContent_MakeAvailable(protobuf)
@@ -124,10 +133,10 @@ if(SUBSPACE_PYTHON)
     FetchContent_MakeAvailable(pybind11)
 endif()
 
+#add to get proto/subspace.pb.h working (build dir first so generated files win)
+include_directories(${CMAKE_CURRENT_BINARY_DIR})
 #add to get */file.h includes working
 include_directories(${CMAKE_CURRENT_SOURCE_DIR})
-#add to get proto/subspace.pb.h working
-include_directories(${CMAKE_CURRENT_BINARY_DIR})
 # --- Subspace Tests Target ---
 # Corresponds to //subspace/tests:tests
 enable_testing() # Enable CTest for running tests