1 files changed, 55 insertions, 0 deletions
diff --git a/dom/encoding/TextEncoder.cpp b/dom/encoding/TextEncoder.cpp
new file mode 100644
index 0000000000..68ee4aa02d
--- /dev/null
+++ b/dom/encoding/TextEncoder.cpp
@@ -0,0 +1,55 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/TextEncoder.h"
+#include "mozilla/CheckedInt.h"
+#include "mozilla/ErrorResult.h"
+#include "mozilla/UniquePtrExtensions.h"
+#include "nsReadableUtils.h"
+
+namespace mozilla::dom {
+
+void TextEncoder::Encode(JSContext* aCx, JS::Handle<JSObject*> aObj,
+                         const nsACString& aUtf8String,
+                         JS::MutableHandle<JSObject*> aRetval,
+                         ErrorResult& aRv) {
+  JSAutoRealm ar(aCx, aObj);
+  JSObject* outView = Uint8Array::Create(aCx, aUtf8String, aRv);
+  if (aRv.Failed()) {
+    return;
+  }
+
+  aRetval.set(outView);
+}
+
+void TextEncoder::EncodeInto(JSContext* aCx, JS::Handle<JSString*> aSrc,
+                             const Uint8Array& aDst,
+                             TextEncoderEncodeIntoResult& aResult,
+                             OOMReporter& aError) {
+  DebugOnly<size_t> dstLength = 0;
+  auto maybe = aDst.ProcessData(
+      [&](const Span<uint8_t>& aData, JS::AutoCheckCannotGC&&) {
+        dstLength = aData.Length();
+        return JS_EncodeStringToUTF8BufferPartial(aCx, aSrc,
+                                                  AsWritableChars(aData));
+      });
+  if (!maybe) {
+    aError.ReportOOM();
+    return;
+  }
+  size_t read;
+  size_t written;
+  std::tie(read, written) = *maybe;
+  MOZ_ASSERT(written <= dstLength);
+  aResult.mRead.Construct() = read;
+  aResult.mWritten.Construct() = written;
+}
+
+void TextEncoder::GetEncoding(nsACString& aEncoding) {
+  aEncoding.AssignLiteral("utf-8");
+}
+
+}  // namespace mozilla::dom