feat: Add ArrayBuffer.copy(data:)

packages/react-native-nitro-modules/ios/core/ArrayBufferHolder.swift

@@ -46,7 +46,7 @@ public extension ArrayBufferHolder {
     }
     return ArrayBufferHolder.makeBuffer(data, size, deleteFunc)
   }
-
+  
   /**
    * Copy the given `ArrayBufferHolder` into a new **owning** `ArrayBufferHolder`.
    */
@@ -60,4 +60,14 @@ public extension ArrayBufferHolder {
     }
     return ArrayBufferHolder.makeBuffer(data, other.size, deleteFunc)
   }
+
+  /**
+   * Copy the given `Data` into a new **owning** `ArrayBufferHolder`.
+   */
+  static func copy(data: Data) throws -> ArrayBufferHolder {
+    let pointer = try UnsafeMutablePointer<UInt8>.init(copyData: data)
+    return .wrap(dataWithoutCopy: pointer, size: data.count) {
+      pointer.deallocate()
+    }
+  }
 }

packages/react-native-nitro-modules/ios/utils/UnsafeMutablePointer+Data.swift

@@ -0,0 +1,28 @@
+//
+//  SwiftClosure.swift
+//  NitroModules
+//
+//  Created by Marc Rousavy on 07.01.24.
+//
+
+import Foundation
+
+public extension UnsafeMutablePointer<UInt8> {
+  /**
+   * Create a new `UnsafeMutablePointer<UInt8>` by copying
+   * the contents of the given `data`.
+   */
+  init(copyData data: Data) throws {
+    let byteCount = data.count
+    let newPointer = UnsafeMutablePointer<UInt8>.allocate(capacity: byteCount)
+
+    try data.withUnsafeBytes { (rawBufferPointer) in
+        guard let baseAddress = rawBufferPointer.baseAddress else {
+          throw RuntimeError.error(withMessage: "Cannot get baseAddress of Data!")
+        }
+        memcpy(newPointer, baseAddress, byteCount)
+    }
+
+    self.init(newPointer)
+  }
+}