feat: support android platform cross build

.github/workflows/android_build.yml

@@ -0,0 +1,188 @@
+name: android-cross-build
+
+on:
+  push:
+    branches: [ "main" ]
+    paths-ignore:
+      - '**.md'
+  merge_group:
+  pull_request:
+    branches: [ "main" ]
+    paths-ignore:
+      - '**.md'
+  workflow_dispatch:
+
+jobs:
+  build-android:
+    # sdkmanager and other Android tools are x86‑only; ARM runners fail with exit code 1
+    # switch back to an x86 image so the setup-android action can install the SDK
+    runs-on: ubuntu-24.04
+    strategy:
+      fail-fast: false
+      matrix:
+        abi: [x86_64]
+        api: [21]
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Cache dependencies
+        uses: actions/cache@v3
+        with:
+          path: |
+            ~/.ccache
+          key: ${{ runner.os }}-dependencies-cache-${{ hashFiles('**/CMakeLists.txt', 'thirdparty/**') }}-stl-fix
+
+      - name: Install dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends \
+            cmake ninja-build git ca-certificates python3 \
+            build-essential make ccache
+
+      - name: Setup Java 17
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '17'
+
+      - name: Setup Android SDK
+        uses: android-actions/setup-android@v3
+
+      - name: Install NDK (side by side)
+        shell: bash
+        run: |
+          sdkmanager "ndk;26.1.10909125"
+
+      - name: Cache host protoc build
+        uses: actions/cache@v3
+        with:
+          path: build-host
+          key: ${{ runner.os }}-host-protoc-${{ hashFiles('src/**', 'CMakeLists.txt') }}-stl-fix
+          restore-keys: |
+            ${{ runner.os }}-host-protoc-
+
+      - name: Use host env to compile protoc
+        shell: bash
+        run: |
+          git submodule update --init
+          if [ ! -d "build-host" ]; then
+            export CCACHE_BASEDIR="$GITHUB_WORKSPACE"
+            export CCACHE_NOHASHDIR=1
+            export CCACHE_SLOPPINESS=clang_index_store,file_stat_matches,include_file_mtime,locale,time_macros
+
+            cmake -S . -B build-host -G Ninja \
+              -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+              -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+            cmake --build build-host --target protoc --parallel
+          else
+            echo "Using cached host protoc build"
+          fi
+
+      - name: Cache Android build
+        uses: actions/cache@v3
+        with:
+          path: build-android-${{ matrix.abi }}
+          key: ${{ runner.os }}-android-build-${{ matrix.abi }}-${{ hashFiles('src/**', 'CMakeLists.txt', 'cmake/**', 'thirdparty/**') }}-stl-fix-3
+
+      - name: Configure and Build
+        shell: bash
+        run: |
+          git submodule foreach --recursive 'git stash --include-untracked'
+
+          export ANDROID_SDK_ROOT="$ANDROID_HOME"
+          export ANDROID_NDK_HOME="$ANDROID_SDK_ROOT/ndk/26.1.10909125"
+
+          export CCACHE_BASEDIR="$GITHUB_WORKSPACE"
+          export CCACHE_NOHASHDIR=1
+          export CCACHE_SLOPPINESS=clang_index_store,file_stat_matches,include_file_mtime,locale,time_macros
+
+          if [ ! -d "build-android-${{ matrix.abi }}" ]; then
+            cmake -S . -B build-android-${{ matrix.abi }} -G Ninja \
+              -DCMAKE_BUILD_TYPE=Release \
+              -DCMAKE_TOOLCHAIN_FILE="$ANDROID_NDK_HOME/build/cmake/android.toolchain.cmake" \
+              -DANDROID_ABI=${{ matrix.abi }} \
+              -DANDROID_PLATFORM=android-${{ matrix.api }} \
+              -DANDROID_STL=c++_static \
+              -DBUILD_PYTHON_BINDINGS=OFF \
+              -DENABLE_NATIVE=OFF \
+              -DAUTO_DETECT_ARCH=OFF \
+              -DBUILD_TOOLS=OFF \
+              -DGLOBAL_CC_PROTOBUF_PROTOC="$GITHUB_WORKSPACE/build-host/bin/protoc" \
+              -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+              -DCMAKE_CXX_COMPILER_LAUNCHER=ccache \
+              -DCMAKE_VERBOSE_MAKEFILE=ON
+            cmake --build build-android-${{ matrix.abi }} --parallel --verbose
+          else
+            echo "Using cached Android build directory"
+          fi
+
+      - name: Cache examples build
+        uses: actions/cache@v3
+        with:
+          path: examples/c++/build-android-examples-${{ matrix.abi }}
+          key: ${{ runner.os }}-examples-build-${{ matrix.abi }}-${{ hashFiles('examples/c++/**', 'CMakeLists.txt', 'src/**') }}-stl-fix-3
+
+      - name: Build examples
+        shell: bash
+        run: |
+          export ANDROID_SDK_ROOT="$ANDROID_HOME"
+          export ANDROID_NDK_HOME="$ANDROID_SDK_ROOT/ndk/26.1.10909125"
+
+          if [ ! -d "examples/c++/build-android-examples-${{ matrix.abi }}" ]; then
+            cmake -S examples/c++ -B examples/c++/build-android-examples-${{ matrix.abi }} -G Ninja \
+              -DCMAKE_TOOLCHAIN_FILE="$ANDROID_NDK_HOME/build/cmake/android.toolchain.cmake" \
+              -DANDROID_ABI=${{ matrix.abi }} \
+              -DANDROID_PLATFORM=android-${{ matrix.api }} \
+              -DANDROID_STL=c++_static \
+              -DCMAKE_BUILD_TYPE=Release \
+              -DCMAKE_INTERPROCEDURAL_OPTIMIZATION=ON \
+              -DHOST_BUILD_DIR="build-android-${{ matrix.abi }}" \
+              -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+              -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+            cmake --build examples/c++/build-android-examples-${{ matrix.abi }} --parallel
+          else
+            echo "Using cached examples build"
+          fi
+
+      - name: Run on Android emulator (arm64) and verify
+        uses: reactivecircus/android-emulator-runner@v2
+        with:
+          api-level: ${{ matrix.api }}
+          arch: ${{ matrix.abi }}
+          # target: google_apis
+          # emulator-options: -no-window -gpu swiftshader_indirect -noaudio -no-boot-anim -netdelay none -netspeed full
+          # disable-animations: true
+          script: |
+            adb wait-for-device
+
+            echo "Device ABI:"
+            adb shell getprop ro.product.cpu.abi
+            adb shell getprop ro.product.cpu.abilist
+
+            echo "Checking binary sizes:"
+            ls -lah examples/c++/build-android-examples-${{ matrix.abi }}/
+
+            # Push executables to device
+            adb push examples/c++/build-android-examples-${{ matrix.abi }}/ailego-example /data/local/tmp/
+            adb push examples/c++/build-android-examples-${{ matrix.abi }}/core-example /data/local/tmp/
+            adb push examples/c++/build-android-examples-${{ matrix.abi }}/db-example /data/local/tmp/
+
+            adb shell chmod 755 /data/local/tmp/ailego-example
+            adb shell chmod 755 /data/local/tmp/core-example
+            adb shell chmod 755 /data/local/tmp/db-example
+
+            echo "File info on device:"
+            adb shell ls -la /data/local/tmp/ailego-example
+            adb shell ls -la /data/local/tmp/core-example
+            adb shell ls -la /data/local/tmp/db-example
+
+            echo "Running ailego example:"
+            adb shell 'cd /data/local/tmp && ./ailego-example'
+
+            echo "Running core example:"
+            adb shell 'cd /data/local/tmp && ./core-example'
+
+            echo "Running db example:"
+            adb shell 'cd /data/local/tmp && ./db-example'

.gitignore

@@ -5,7 +5,6 @@ build*
 bin/*
 lib/*
 var/*
-thirdparty
 venv*
 tests/integration/conf/*
 tests/de_integration/conf/*
@@ -48,3 +47,5 @@ yarn-debug.log*
 yarn-error.log*
 
 allure-*
+
+!build_android.sh

.gitmodules

@@ -11,6 +11,7 @@
 [submodule "thirdparty/rocksdb/rocksdb-8.1.1"]
 	path = thirdparty/rocksdb/rocksdb-8.1.1
 	url = https://github.com/facebook/rocksdb.git
+	ignore = all
 [submodule "thirdparty/yaml-cpp/yaml-cpp-0.6.3"]
 	path = thirdparty/yaml-cpp/yaml-cpp-0.6.3
 	url = https://github.com/jbeder/yaml-cpp.git

cmake/bazel.cmake

@@ -1313,6 +1313,9 @@ function(cc_proto_library)
 
   _find_protobuf("${CC_ARGS_PROTOBUF_VERSION}")
   set(CC_PROTOBUF_PROTOC ${CC_PROTOBUF_PROTOC_${CC_ARGS_PROTOBUF_VERSION}})
+  if(DEFINED GLOBAL_CC_PROTOBUF_PROTOC)
+    set(CC_PROTOBUF_PROTOC ${GLOBAL_CC_PROTOBUF_PROTOC})
+  endif()
   set(CC_PROTOBUF_INCS ${CC_PROTOBUF_INCS_${CC_ARGS_PROTOBUF_VERSION}})
   set(CC_PROTOBUF_LIBS ${CC_PROTOBUF_LIBS_${CC_ARGS_PROTOBUF_VERSION}})
 

examples/c++/CMakeLists.txt

@@ -7,9 +7,14 @@ set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 # --- Paths to Zvec and dependencies ---
+# Allow custom host build directory, default to "build"
+if(NOT DEFINED HOST_BUILD_DIR)
+    set(HOST_BUILD_DIR "build")
+endif()
+
 set(ZVEC_INCLUDE_DIR ${CMAKE_BINARY_DIR}/../../../src/include)
-set(ZVEC_LIB_DIR ${CMAKE_BINARY_DIR}/../../../build/lib)
-set(ZVEC_DEPENDENCY_LIB_DIR ${CMAKE_BINARY_DIR}/../../../build/external/usr/local/lib)
+set(ZVEC_LIB_DIR ${CMAKE_BINARY_DIR}/../../../${HOST_BUILD_DIR}/lib)
+set(ZVEC_DEPENDENCY_LIB_DIR ${CMAKE_BINARY_DIR}/../../../${HOST_BUILD_DIR}/external/usr/local/lib)
 
 # Add include and library search paths
 include_directories(${ZVEC_INCLUDE_DIR})
@@ -84,6 +89,16 @@ elseif(APPLE)
         zvec-ailego
         ${zvec_core_deps}
     )
+elseif(ANDROID)
+    target_link_libraries(zvec-core INTERFACE
+        -Wl,--whole-archive
+        zvec_core
+        -Wl,--no-whole-archive
+        -Wl,--start-group
+        zvec-ailego
+        ${zvec_core_deps}
+        -Wl,--end-group
+    )
 else()
     message(FATAL_ERROR "Unsupported platform: ${CMAKE_SYSTEM_NAME}")
 endif()
@@ -106,6 +121,17 @@ elseif(APPLE)
         zvec-ailego
         ${zvec_db_deps}
     )
+elseif(ANDROID)
+    target_link_libraries(zvec-db INTERFACE
+        zvec_db
+        zvec-core
+        zvec-ailego
+        -Wl,--start-group
+        ${zvec_db_deps}
+        -Wl,--end-group
+    )
+else()
+    message(FATAL_ERROR "Unsupported platform: ${CMAKE_SYSTEM_NAME}")
 endif()
 
 
@@ -114,6 +140,11 @@ add_executable(db-example db/main.cc)
 target_link_libraries(db-example PRIVATE
     zvec-db
 )
+if(ANDROID)
+    target_link_libraries(db-example PRIVATE
+        log
+    )
+endif()
 
 add_executable(core-example core/main.cc)
 target_link_libraries(core-example PRIVATE
@@ -124,3 +155,24 @@ add_executable(ailego-example ailego/main.cc)
 target_link_libraries(ailego-example PRIVATE
     zvec-ailego
 )
+
+# Strip symbols to reduce executable size
+if(CMAKE_BUILD_TYPE STREQUAL "Release" AND ANDROID)
+    add_custom_command(TARGET db-example POST_BUILD
+        COMMAND ${CMAKE_STRIP} "$<TARGET_FILE:db-example>"
+        COMMENT "Stripping symbols from db-example")
+    add_custom_command(TARGET core-example POST_BUILD
+        COMMAND ${CMAKE_STRIP} "$<TARGET_FILE:core-example>"
+        COMMENT "Stripping symbols from core-example")
+    add_custom_command(TARGET ailego-example POST_BUILD
+        COMMAND ${CMAKE_STRIP} "$<TARGET_FILE:ailego-example>"
+        COMMENT "Stripping symbols from ailego-example")
+endif()
+
+# Optimize for size
+if(CMAKE_BUILD_TYPE STREQUAL "Release" AND ANDROID)
+    set_property(TARGET db-example core-example ailego-example
+                 PROPERTY COMPILE_FLAGS "-Os")
+    set_property(TARGET db-example core-example ailego-example
+                 PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)
+endif()

pyproject.toml

@@ -193,6 +193,7 @@ exclude = [
     ".git/",
     ".venv/",
     "venv/",
+    "thirdparty",
 ]
 
 [tool.ruff.lint]

scripts/build_android.sh

@@ -0,0 +1,65 @@
+#!/bin/bash
+set -e
+CURRENT_DIR=$(pwd)
+
+ABI=${1:-"arm64-v8a"}
+API_LEVEL=${2:-21}
+BUILD_TYPE=${3:-"Release"}
+
+# step1: use host env to compile protoc
+echo "step1: building protoc for host..."
+HOST_BUILD_DIR="build_host"
+mkdir -p $HOST_BUILD_DIR
+cd $HOST_BUILD_DIR
+
+cmake -DCMAKE_BUILD_TYPE="$BUILD_TYPE" ..
+make -j protoc
+PROTOC_EXECUTABLE=$CURRENT_DIR/$HOST_BUILD_DIR/bin/protoc
+cd $CURRENT_DIR
+
+echo "step1: Done!!!"
+
+# step2: cross build zvec based on android ndk
+echo "step2: building zvec for android..."
+
+# reset thirdparty directory
+git submodule foreach --recursive 'git stash --include-untracked'
+
+export ANDROID_SDK_ROOT=$HOME/Library/Android/sdk
+export ANDROID_HOME=$ANDROID_SDK_ROOT
+export ANDROID_NDK_HOME=$ANDROID_SDK_ROOT/ndk/28.2.13676358
+export CMAKE_TOOLCHAIN_FILE=$ANDROID_NDK_HOME/build/cmake/android.toolchain.cmake
+
+export PATH=$PATH:$ANDROID_SDK_ROOT/cmdline-tools/latest/bin
+export PATH=$PATH:$ANDROID_SDK_ROOT/platform-tools
+export PATH=$PATH:$ANDROID_NDK_HOME
+
+if [ -z "$ANDROID_NDK_HOME" ]; then
+    echo "error: ANDROID_NDK_HOME env not set"
+    echo "please install NDK and set env variable ANDROID_NDK_HOME"
+    exit 1
+fi
+
+BUILD_DIR="build_android_${ABI}"
+mkdir -p $BUILD_DIR
+cd $BUILD_DIR
+
+echo "configure CMake..."
+cmake \
+    -DANDROID_NDK="$ANDROID_NDK_HOME" \
+    -DCMAKE_TOOLCHAIN_FILE="$ANDROID_NDK_HOME/build/cmake/android.toolchain.cmake" \
+    -DANDROID_ABI="$ABI" \
+    -DANDROID_NATIVE_API_LEVEL="$API_LEVEL" \
+    -DANDROID_STL="c++_static" \
+    -DCMAKE_BUILD_TYPE="$BUILD_TYPE" \
+    -DBUILD_PYTHON_BINDINGS=OFF \
+    -DBUILD_TOOLS=OFF \
+    -DCMAKE_INSTALL_PREFIX="./install" \
+    -DGLOBAL_CC_PROTOBUF_PROTOC=$PROTOC_EXECUTABLE \
+    ../
+
+echo "building..."
+CORE_COUNT=$(sysctl -n hw.ncpu)
+make -j$CORE_COUNT
+
+echo "step2: Done!!!"

src/ailego/CMakeLists.txt

@@ -3,7 +3,7 @@ include(${PROJECT_ROOT_DIR}/cmake/option.cmake)
 
 find_package(Threads REQUIRED)
 
-if(UNIX AND NOT APPLE)
+if(UNIX AND NOT APPLE AND NOT ANDROID)
     find_library(LIB_RT NAMES rt)
 else()
     set(LIB_RT "")