1 files changed, 62 insertions, 0 deletions
diff --git a/desktop/node_modules/@electron/asar/lib/integrity.js b/desktop/node_modules/@electron/asar/lib/integrity.js
new file mode 100644
index 0000000..6fabee4
--- /dev/null
+++ b/desktop/node_modules/@electron/asar/lib/integrity.js
@@ -0,0 +1,62 @@
+const crypto = require('crypto')
+const fs = require('fs')
+const stream = require('stream')
+const { promisify } = require('util')
+
+const ALGORITHM = 'SHA256'
+// 4MB default block size
+const BLOCK_SIZE = 4 * 1024 * 1024
+
+const pipeline = promisify(stream.pipeline)
+
+function hashBlock (block) {
+  return crypto.createHash(ALGORITHM).update(block).digest('hex')
+}
+
+async function getFileIntegrity (path) {
+  const fileHash = crypto.createHash(ALGORITHM)
+
+  const blocks = []
+  let currentBlockSize = 0
+  let currentBlock = []
+
+  await pipeline(
+    fs.createReadStream(path),
+    new stream.PassThrough({
+      decodeStrings: false,
+      transform (_chunk, encoding, callback) {
+        fileHash.update(_chunk)
+
+        function handleChunk (chunk) {
+          const diffToSlice = Math.min(BLOCK_SIZE - currentBlockSize, chunk.byteLength)
+          currentBlockSize += diffToSlice
+          currentBlock.push(chunk.slice(0, diffToSlice))
+          if (currentBlockSize === BLOCK_SIZE) {
+            blocks.push(hashBlock(Buffer.concat(currentBlock)))
+            currentBlock = []
+            currentBlockSize = 0
+          }
+          if (diffToSlice < chunk.byteLength) {
+            handleChunk(chunk.slice(diffToSlice))
+          }
+        }
+        handleChunk(_chunk)
+        callback()
+      },
+      flush (callback) {
+        blocks.push(hashBlock(Buffer.concat(currentBlock)))
+        currentBlock = []
+        callback()
+      }
+    })
+  )
+
+  return {
+    algorithm: ALGORITHM,
+    hash: fileHash.digest('hex'),
+    blockSize: BLOCK_SIZE,
+    blocks: blocks
+  }
+}
+
+module.exports = getFileIntegrity