1 files changed, 59 insertions, 0 deletions
diff --git a/netwerk/base/MemoryDownloader.h b/netwerk/base/MemoryDownloader.h
new file mode 100644
index 0000000000..8b5700f5bf
--- /dev/null
+++ b/netwerk/base/MemoryDownloader.h
@@ -0,0 +1,59 @@
+/* -*- Mode: C++; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+#ifndef mozilla_net_MemoryDownloader_h__
+#define mozilla_net_MemoryDownloader_h__
+
+#include "mozilla/UniquePtr.h"
+#include "nsCOMPtr.h"
+#include "nsIStreamListener.h"
+#include "nsTArray.h"
+
+/**
+ * mozilla::net::MemoryDownloader
+ *
+ * This class is similar to nsIDownloader, but stores the downloaded
+ * stream in memory instead of a file.  Ownership of the temporary
+ * memory is transferred to the observer when download is complete;
+ * there is no need to retain a reference to the downloader.
+ */
+
+namespace mozilla {
+namespace net {
+
+class MemoryDownloader final : public nsIStreamListener {
+ public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIREQUESTOBSERVER
+  NS_DECL_NSISTREAMLISTENER
+
+  using Data = mozilla::UniquePtr<FallibleTArray<uint8_t>>;
+
+  class IObserver : public nsISupports {
+   public:
+    // Note: aData may be null if (and only if) aStatus indicates failure.
+    virtual void OnDownloadComplete(MemoryDownloader* aDownloader,
+                                    nsIRequest* aRequest, nsresult aStatus,
+                                    Data aData) = 0;
+  };
+
+  explicit MemoryDownloader(IObserver* aObserver);
+
+ private:
+  virtual ~MemoryDownloader() = default;
+
+  static nsresult ConsumeData(nsIInputStream* in, void* closure,
+                              const char* fromRawSegment, uint32_t toOffset,
+                              uint32_t count, uint32_t* writeCount);
+
+  RefPtr<IObserver> mObserver;
+  Data mData;
+  nsresult mStatus;
+};
+
+}  // namespace net
+}  // namespace mozilla
+
+#endif  // mozilla_net_MemoryDownloader_h__