Initial

resources/app/node_modules/unzipper/lib/parseBuffer.js

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+const parseUIntLE = function(buffer, offset, size) {
+  let result;
+  switch(size) {
+    case 1:
+      result = buffer.readUInt8(offset);
+      break;
+    case 2:
+      result = buffer.readUInt16LE(offset);
+      break;
+    case 4:
+      result = buffer.readUInt32LE(offset);
+      break;
+    case 8:
+      result = Number(buffer.readBigUInt64LE(offset));
+      break;
+    default:
+      throw new Error('Unsupported UInt LE size!');
+  }
+  return result;
+};
+
+/**
+ * Parses sequential unsigned little endian numbers from the head of the passed buffer according to
+ * the specified format passed.  If the buffer is not large enough to satisfy the full format,
+ * null values will be assigned to the remaining keys.
+ * @param {*} buffer The buffer to sequentially extract numbers from.
+ * @param {*} format Expected format to follow when extrcting values from the buffer.  A list of list entries
+ * with the following structure:
+ * [
+ *   [
+ *     <key>,  // Name of the key to assign the extracted number to.
+ *     <size>  // The size in bytes of the number to extract. possible values are 1, 2, 4, 8.
+ *   ],
+ *   ...
+ * ]
+ * @returns An object with keys set to their associated extracted values.
+ */
+const parse = function(buffer, format) {
+  const result = {};
+  let offset = 0;
+  for(const [key, size] of format) {
+    if(buffer.length >= offset + size) {
+      result[key] = parseUIntLE(buffer, offset, size);
+    }
+    else {
+      result[key] = null;
+    }
+    offset += size;
+  }
+  return result;
+};
+
+module.exports = {
+  parse
+};