chore: update mksnapshot to work with arm*-x64 zips (#27)

* chore: update mksnapshot to work with arm*-x64 zips

* Read mksnapshot args if it is provided

* Update documentation

.circleci/config.yml

@@ -40,7 +40,7 @@ jobs:
 
   install-test-osx:
     macos:
-        xcode: "9.0"
+        xcode: "11.1.0"
     steps:
       - checkout
 

README.md

@@ -41,3 +41,27 @@ ELECTRON_MIRROR="https://npm.taobao.org/mirrors/electron/"
 # Example of requested URL: http://localhost:8080/1.2.0/mksnapshot-v1.2.0-darwin-x64.zip
 ELECTRON_MIRROR="http://localhost:8080/"
 ```
+## Generating snapshots for ARM hardware
+
+If you need to generate snapshots for Linux on 32 bit ARM, Linux on ARM64, or Windows on ARM64 you will need to install a cross arch mksnapshot on an Intel x64 machine.  To do so, set the npm config `arch` to the proper arch and then run `npm install --save-dev electron-mksnapshot`.  For example:
+
+### Linux on ARM64
+From an Intel x64 Linux OS run:
+```sh
+npm config set arch arm64
+npm install --save-dev electron-mksnapshot
+```
+
+### Linux on 32 bit ARM 
+From an Intel x64 Linux OS run:
+```sh
+npm config set arch armv7l
+npm install --save-dev electron-mksnapshot
+```
+
+### Windows on ARM (64-bit)
+From an Intel x64 Windows OS run:
+```sh
+npm config set arch arm64
+npm install --save-dev electron-mksnapshot
+```

download-mksnapshot.js

@@ -4,9 +4,25 @@ var electronDownload = require('electron-download')
 var extractZip = require('extract-zip')
 var versionToDownload = require('./package').version
 var archToDownload = process.env.npm_config_arch
-if (archToDownload === 'arm64') {
-  archToDownload = 'arm64-x64'
+
+if (process.arch.indexOf('arm') === 0) {
+  console.log(`WARNING: mksnapshot does not run on ${process.arch}. Download 
+  https://github.com/electron/electron/releases/download/v${versionToDownload}/mksnapshot-v${versionToDownload}-${process.platform}-${process.arch}-x64.zip
+  on a x64 ${process.platform} OS to generate ${archToDownload} snapshots.`)
+  process.exit(1)
+}
+
+if (archToDownload && archToDownload.indexOf('arm') === 0) {
+  if (process.platform !== 'darwin') {
+    archToDownload += '-x64'
+  } else {
+    console.log(`WARNING: mksnapshot for ${archToDownload} is not available on macOS. Download 
+    https://github.com/electron/electron/releases/download/v${versionToDownload}/mksnapshot-v${versionToDownload}-linux-${archToDownload}-x64.zip
+    on a x64 Linux OS to generate ${archToDownload} snapshots.`)
+    process.exit(1)
+  }
 }
+
 function download (version, callback) {
   electronDownload({
     version: version,
@@ -23,9 +39,12 @@ function processDownload (err, zipPath) {
   extractZip(zipPath, { dir: path.join(__dirname, 'bin') }, function (error) {
     if (error != null) throw error
     if (process.platform !== 'win32') {
-      fs.chmod(path.join(__dirname, 'bin', 'mksnapshot'), '755', function (error) {
-        if (error != null) throw error
-      })
+      var mksnapshotPath = path.join(__dirname, 'bin', 'mksnapshot')
+      if (fs.existsSync(mksnapshotPath)) {
+        fs.chmod(path.join(__dirname, 'bin', 'mksnapshot'), '755', function (error) {
+          if (error != null) throw error
+        })
+      }
     }
   })
 }

mksnapshot.js

@@ -5,6 +5,11 @@ const { spawnSync } = require('child_process')
 const path = require('path')
 const temp = require('temp').track()
 const workingDir = temp.mkdirSync('mksnapshot-workdir')
+const crossArchDirs = [
+  'clang_x86_v8_arm',
+  'clang_x64_v8_arm64',
+  'win_clang_x64'
+]
 
 function getBinaryPath (binary, binaryPath) {
   if (process.platform === 'win32') {
@@ -38,11 +43,6 @@ if (outDirIdx > -1) {
 if (args.includes('--startup_blob')) {
   console.log('--startup_blob argument not supported. Use --output_dir to specify where to output snapshot_blob.bin')
   process.exit(1)
-} else {
-  mksnapshotArgs = mksnapshotArgs.concat(['--startup_blob', 'snapshot_blob.bin'])
-}
-if (!mksnapshotArgs.includes('--turbo_instruction_scheduling')) {
-  mksnapshotArgs.push('--turbo_instruction_scheduling')
 }
 
 const mksnapshotDir = path.join(__dirname, 'bin')
@@ -52,13 +52,48 @@ const mksnapshotDir = path.join(__dirname, 'bin')
 // directory.
 fs.copySync(mksnapshotDir, workingDir)
 
+const argsFile = path.join(mksnapshotDir, 'mksnapshot_args')
+let mksnapshotBinaryDir = workingDir
+if (fs.existsSync(argsFile)) {
+  // Use args from args file if it is provided as these match what is used to generate the original snapshot
+  const mksnapshotArgsFile = fs.readFileSync(argsFile, 'utf8')
+  const newlineRegEx = /(\r\n|\r|\n)/g
+  const mksnapshotArgsFromFile = mksnapshotArgsFile.split(newlineRegEx).filter((arg) => {
+    return (!arg.match(newlineRegEx) && arg !== '')
+  })
+  const mksnapshotBinaryPath = path.parse(mksnapshotArgsFromFile[0])
+  if (mksnapshotBinaryPath.dir) {
+    mksnapshotBinaryDir = path.join(workingDir, mksnapshotBinaryPath.dir)
+  }
+  mksnapshotArgs = mksnapshotArgs.concat(mksnapshotArgsFromFile.slice(1))
+} else {
+  mksnapshotArgs = mksnapshotArgs.concat(['--startup_blob', 'snapshot_blob.bin'])
+  if (!mksnapshotArgs.includes('--turbo_instruction_scheduling')) {
+    mksnapshotArgs.push('--turbo_instruction_scheduling')
+  }
+  if (!fs.existsSync(getBinaryPath('mksnapshot', mksnapshotBinaryDir))) {
+    const matchingDir = crossArchDirs.find((crossArchDir) => {
+      const candidatePath = path.join(mksnapshotBinaryDir, crossArchDir)
+      if (fs.existsSync(getBinaryPath('mksnapshot', candidatePath))) {
+        return true
+      }
+    })
+    if (matchingDir) {
+      mksnapshotBinaryDir = path.join(workingDir, matchingDir)
+    } else {
+      console.log('ERROR: Could not find mksnapshot')
+      process.exit(1)
+    }
+  }
+}
+
 const options = {
   cwd: workingDir,
   env: process.env,
   stdio: 'inherit'
 }
 
-const mksnapshotCommand = getBinaryPath('mksnapshot', workingDir)
+const mksnapshotCommand = getBinaryPath('mksnapshot', mksnapshotBinaryDir)
 const mksnapshotProcess = spawnSync(mksnapshotCommand, mksnapshotArgs, options)
 if (mksnapshotProcess.status !== 0) {
   let code = mksnapshotProcess.status
@@ -75,7 +110,7 @@ if (args.includes('--help')) {
 fs.copyFileSync(path.join(workingDir, 'snapshot_blob.bin'),
   path.join(outputDir, 'snapshot_blob.bin'))
 
-const v8ContextGenCommand = getBinaryPath('v8_context_snapshot_generator', workingDir)
+const v8ContextGenCommand = getBinaryPath('v8_context_snapshot_generator', mksnapshotBinaryDir)
 const v8ContextGenArgs = [
   `--output_file=${path.join(outputDir, 'v8_context_snapshot.bin')}`
 ]