[github-actions] Add build workflow
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..6fcc2c7
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,214 @@
+name: build
+
+on: [push]
+
+jobs:
+  build-linux-ubuntu:
+    runs-on: ubuntu-latest
+    steps:
+    - name: install dependencies
+      run: |
+          sudo apt-get install cython
+    - name: prepare environment
+      run: |
+          echo "target_triplet=`gcc -dumpmachine`" >> $GITHUB_ENV
+    - name: fetch libplist
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libplist-latest_${{env.target_triplet}}
+        repo: libimobiledevice/libplist
+    - name: fetch libusbmuxd
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libusbmuxd-latest_${{env.target_triplet}}
+        repo: libimobiledevice/libusbmuxd
+    - name: fetch libimobiledevice-glue
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libimobiledevice-glue-latest_${{env.target_triplet}}
+        repo: libimobiledevice/libimobiledevice-glue
+    - name: install external dependencies
+      run: |
+          mkdir extract
+          for I in *.tar; do
+            tar -C extract -xvf $I
+          done
+          sudo cp -r extract/* /
+          sudo ldconfig
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 0
+    - name: autogen
+      run: ./autogen.sh PKG_CONFIG_PATH=/usr/local/lib/pkgconfig LDFLAGS="-Wl,-rpath=/usr/local/lib"
+    - name: make
+      run: make
+    - name: make install
+      run: sudo make install
+    - name: prepare artifact
+      run: |
+          mkdir -p dest
+          DESTDIR=`pwd`/dest make install
+          tar -C dest -cf libimobiledevice.tar usr
+    - name: publish artifact
+      uses: actions/upload-artifact@v2
+      with:
+        name: libimobiledevice-latest_${{env.target_triplet}}
+        path: libimobiledevice.tar
+  build-macOS:
+    runs-on: macOS-latest
+    steps:
+    - name: install dependencies
+      run: |
+          if test -x "`which port`"; then
+            sudo port install libtool autoconf automake pkgconfig
+          else
+            brew install libtool autoconf automake pkgconfig
+          fi
+          pip install cython
+      shell: bash
+    - name: fetch libplist
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libplist-latest_macOS
+        repo: libimobiledevice/libplist
+    - name: fetch libusbmuxd
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libusbmuxd-latest_macOS
+        repo: libimobiledevice/libusbmuxd
+    - name: fetch libimobiledevice-glue
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libimobiledevice-glue-latest_macOS
+        repo: libimobiledevice/libimobiledevice-glue
+    - name: install external dependencies
+      run: |
+          mkdir extract
+          for I in *.tar; do
+            tar -C extract -xvf $I
+          done
+          sudo cp -r extract/* /
+    - uses: actions/checkout@v2
+    - name: install additional requirements
+      run: |
+          mkdir -p lib
+          curl -o lib/libcrypto.35.tbd -Ls \
+              https://gist.github.com/nikias/94c99fd145a75a5104415e5117b0cafa/raw/5209dfbff5a871a14272afe4794e76eb4cf6f062/libcrypto.35.tbd
+          curl -o lib/libssl.35.tbd -Ls \
+              https://gist.github.com/nikias/94c99fd145a75a5104415e5117b0cafa/raw/5209dfbff5a871a14272afe4794e76eb4cf6f062/libssl.35.tbd
+          echo "LIBSSL=`pwd`/lib/libssl.35.tbd" >> $GITHUB_ENV
+          echo "LIBCRYPTO=`pwd`/lib/libcrypto.35.tbd" >> $GITHUB_ENV
+          LIBRESSL_VER=2.2.7
+          echo "LIBRESSL_VER=$LIBRESSL_VER" >> $GITHUB_ENV
+          FILENAME="libressl-$LIBRESSL_VER.tar.gz"
+          curl -o $FILENAME -Ls "https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/$FILENAME"
+          mkdir -p deps
+          tar -C deps -xzf $FILENAME
+          echo "DEPSDIR=`pwd`/deps" >> $GITHUB_ENV
+    - name: autogen
+      run: |
+          ./autogen.sh PKG_CONFIG_PATH=/usr/local/lib/pkgconfig --enable-debug \
+              openssl_CFLAGS="-I${{ env.DEPSDIR }}/libressl-${{ env.LIBRESSL_VER }}/include" \
+              openssl_LIBS="-Xlinker ${{ env.LIBSSL }} -Xlinker ${{ env.LIBCRYPTO }}"
+    - name: make
+      run: make
+    - name: make install
+      run: sudo make install
+    - name: prepare artifact
+      run: |
+          mkdir -p dest
+          DESTDIR=`pwd`/dest make install
+          tar -C dest -cf libimobiledevice.tar usr
+    - name: publish artifact
+      uses: actions/upload-artifact@v2
+      with:
+        name: libimobiledevice-latest_macOS
+        path: libimobiledevice.tar
+  build-windows:
+    runs-on: windows-latest
+    defaults:
+      run:
+        shell: msys2 {0}
+    strategy:
+      fail-fast: false
+      matrix:
+        include: [
+          { msystem: MINGW64, arch: x86_64 },
+          { msystem: MINGW32, arch: i686   }
+        ]
+    steps:
+    - uses: msys2/setup-msys2@v2
+      with:
+        msystem: ${{ matrix.msystem }}
+        release: false
+        update: false
+        install: >-
+          base-devel
+          git
+          mingw-w64-${{ matrix.arch }}-gcc
+          make
+          libtool
+          autoconf
+          automake-wrapper
+    - name: prepare environment
+      run: |
+          dest=`echo ${{ matrix.msystem }} |tr [:upper:] [:lower:]`
+          echo "dest=$dest" >> $GITHUB_ENV
+          echo "target_triplet=`gcc -dumpmachine`" >> $GITHUB_ENV
+    - name: fetch libplist
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libplist-latest_${{ matrix.arch }}-${{ env.dest }}
+        repo: libimobiledevice/libplist
+    - name: fetch libusbmuxd
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libusbmuxd-latest_${{ matrix.arch }}-${{ env.dest }}
+        repo: libimobiledevice/libusbmuxd
+    - name: fetch libimobiledevice-glue
+      uses: dawidd6/action-download-artifact@v2
+      with:
+        github_token: ${{secrets.GITHUB_TOKEN}}
+        workflow: build.yml
+        name: libimobiledevice-glue-latest_${{ matrix.arch }}-${{ env.dest }}
+        repo: libimobiledevice/libimobiledevice-glue
+    - name: install external dependencies
+      run: |
+          mkdir extract
+          for I in *.tar; do
+            tar -C extract -xvf $I
+          done
+          cp -r extract/* /
+    - uses: actions/checkout@v2
+    - name: autogen
+      run: ./autogen.sh CC=gcc CXX=g++
+    - name: make
+      run: make
+    - name: make install
+      run: make install
+    - name: prepare artifact
+      run: |
+          mkdir -p dest
+          DESTDIR=`pwd`/dest make install
+          tar -C dest -cf libimobiledevice.tar ${{ env.dest }}
+    - name: publish artifact
+      uses: actions/upload-artifact@v2
+      with:
+        name: libimobiledevice-latest_${{ matrix.arch }}-${{ env.dest }}
+        path: libimobiledevice.tar