[minor] Build a universal binary to support Apple M1

Fixes #135

Author: lpinca

.github/workflows/ci.yml

@@ -17,12 +17,12 @@ jobs:
           - 14
           - 16
         os:
-          - macOS-latest
+          - macos-11
           - ubuntu-18.04
           - windows-latest
         exclude:
           - arch: x86
-            os: macOS-latest
+            os: macos-11
           - arch: x86
             os: ubuntu-18.04
     steps:
@@ -34,7 +34,13 @@ jobs:
       - run: npm install
       - run: npm test
       - run: npm run prebuild
-        if: matrix.node == 14 && startsWith(github.ref, 'refs/tags/')
+        if:
+          matrix.node == 14 && matrix.os != 'macos-11' && startsWith(github.ref,
+          'refs/tags/')
+      - run: npm run prebuild-darwin-x64+arm64
+        if:
+          matrix.node == 14 && matrix.os == 'macos-11' && startsWith(github.ref,
+          'refs/tags/')
       - run: npm run prebuild-linux-arm
         if:
           matrix.node == 14 && matrix.os == 'ubuntu-18.04' &&
@@ -57,8 +63,8 @@ jobs:
       - run: echo ::set-output name=version::$(git describe --tags)
         id: get_version
       - run:
-          tar -cvf "${{ steps.get_version.outputs.version }}-darwin-x64.tar" -C
-          "prebuilds/macOS-latest" .
+          tar -cvf "${{ steps.get_version.outputs.version
+          }}-darwin-x64+arm64.tar" -C "prebuilds/macos-11" .
       - run:
           tar -cvf "${{ steps.get_version.outputs.version }}-linux-arm.tar" -C
           "prebuilds/ubuntu-18.04" linux-arm

binding.gyp

@@ -3,7 +3,12 @@
     {
       'target_name': 'bufferutil',
       'sources': ['src/bufferutil.c'],
-      'cflags': ['-std=c99']
+      'cflags': ['-std=c99'],
+      'xcode_settings': {
+        'MACOSX_DEPLOYMENT_TARGET': '10.7',
+        'OTHER_CFLAGS': ['-arch x86_64', '-arch arm64'],
+        'OTHER_LDFLAGS': ['-arch x86_64', '-arch arm64']
+      }
     }
   ]
 }

package.json

@@ -9,6 +9,7 @@
   "scripts": {
     "install": "node-gyp-build",
     "prebuild": "prebuildify --napi --strip",
+    "prebuild-darwin-x64+arm64": "prebuildify --arch x64+arm64 --napi --strip",
     "prebuild-linux-arm": "prebuildify-cross -i linux-armv6 -i linux-armv7 -i linux-arm64 --napi --strip",
     "test": "mocha"
   },