Add option to build inside docker container

This allows us to target older versions of GLIBC.

.github/workflows/main.yml

@@ -19,8 +19,56 @@ env:
   LIBUV_CACHE_VERSION: 1
 
 jobs:
-  build:
-    name: 'Build'
+  build_docker:
+    name: 'Build Docker'
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [ release, debug ]
+        bits: [ 64, 32 ]
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: recursive
+
+      - name: Get godot-cpp submodule commit hash
+        shell: bash
+        env:
+          ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+        run: |
+          echo ::set-env name=GODOT_CPP_COMMIT_HASH::$(git ls-tree HEAD addons/godot_xterm/native/thirdparty/godot-cpp -l | cut -d\  -f3)
+      - name: Cache godot-cpp bindings
+        uses: actions/cache@v2
+        id: cache
+        env:
+          cache-name: cache-godot-cpp
+        with:
+          path: addons/godot_xterm/native/thirdparty/godot-cpp
+          key: godot-cpp-${{ matrix.platform }}-${{ matrix.target }}-${{ matrix.bits }}-${{ env.GODOT_CPP_COMMIT_HASH }}-v${{ env.GODOT_CPP_CACHE_VERSION }}
+      - name: Get libuv submodule commit hash
+        shell: bash
+        env:
+          ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+        run: |
+          echo ::set-env name=LIBUV_COMMIT_HASH::$(git ls-tree HEAD addons/godot_xterm/native/thirdparty/libuv -l | cut -d\  -f3)
+
+      # Build inside docker container in order to target older GLIBC versions.
+      - name: Run build script
+        run: |
+          cd addons/godot_xterm/native
+          /bin/bash ./build.sh --target ${{ matrix.target }} --bits ${{ matrix.bits }} --docker
+
+      - name: Upload build artifacts
+        uses: actions/upload-artifact@v2
+        with:
+          name: libgodot-xterm-${{ matrix.target }}
+          path: |
+            addons/godot_xterm/native/bin/*.so
+
+
+  build_native:
+    name: 'Build Native'
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
@@ -154,10 +202,10 @@ jobs:
 
       - name: Upload build artifacts
         uses: actions/upload-artifact@v2
+        if: ${{ matrix.platform != 'linux' }}
         with:
           name: libgodot-xterm-${{ matrix.target }}
           path: |
-            addons/godot_xterm/native/bin/*.so
             addons/godot_xterm/native/bin/*.wasm
             addons/godot_xterm/native/bin/*.dylib
             addons/godot_xterm/native/bin/*.dll
@@ -219,7 +267,7 @@ jobs:
 
   html5_export:
     name: 'HTML5 Export'
-    needs: [ build, export_template ]
+    needs: [ build_docker, build_native, export_template ]
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
@@ -254,7 +302,7 @@ jobs:
 
   test:
     name: 'Test'
-    needs: [ install_plugins, build ]
+    needs: [ install_plugins, build_docker, build_native ]
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false