1 files changed, 66 insertions, 0 deletions
diff --git a/includes/image_io/base/ostream_ref_data_destination.h b/includes/image_io/base/ostream_ref_data_destination.h
new file mode 100644
index 0000000..266e2be
--- /dev/null
+++ b/includes/image_io/base/ostream_ref_data_destination.h
@@ -0,0 +1,66 @@
+#ifndef IMAGE_IO_BASE_OSTREAM_REF_DATA_DESTINATION_H_  // NOLINT
+#define IMAGE_IO_BASE_OSTREAM_REF_DATA_DESTINATION_H_  // NOLINT
+
+#include <iostream>
+#include <string>
+
+#include "image_io/base/data_destination.h"
+#include "image_io/base/message_handler.h"
+
+namespace photos_editing_formats {
+namespace image_io {
+
+/// A DataDestination that writes its output to an ostream held as a reference.
+class OStreamRefDataDestination : public DataDestination {
+ public:
+  /// Constructs an OStreamDataDestination using the given ostream.
+  /// @param ostream_ref The ostream to which data is written.
+  /// @param message_handler An option message handler for writing messages.
+  OStreamRefDataDestination(std::ostream& ostream_ref,
+                            MessageHandler* message_handler)
+      : ostream_ref_(ostream_ref),
+        message_handler_(message_handler),
+        bytes_transferred_(0),
+        has_error_(false) {}
+  OStreamRefDataDestination(const OStreamRefDataDestination&) = delete;
+  OStreamRefDataDestination& operator=(const OStreamRefDataDestination&) =
+      delete;
+
+  /// @param name A name to associate with the ostream. Used for error messages.
+  void SetName(const std::string& name) { name_ = name; }
+
+  /// @return The name associated with the ostream.
+  const std::string& GetName() const { return name_; }
+
+  /// @return The number of bytes written to the ostream.
+  size_t GetBytesTransferred() const override { return bytes_transferred_; }
+
+  /// @return True if errors were encountered while writing to the ostream.
+  bool HasError() const { return has_error_; }
+
+  void StartTransfer() override;
+  TransferStatus Transfer(const DataRange& transfer_range,
+                          const DataSegment& data_segment) override;
+  void FinishTransfer() override;
+
+ private:
+  /// The ostream written to.
+  std::ostream& ostream_ref_;
+
+  /// An optional message handler to write messages to.
+  MessageHandler* message_handler_;
+
+  /// The number of bytes written so far.
+  size_t bytes_transferred_;
+
+  /// A (file) name to associate with the ostream, used with error messages.
+  std::string name_;
+
+  /// If true indicates an error has occurred writing to the ostream.
+  bool has_error_;
+};
+
+}  // namespace image_io
+}  // namespace photos_editing_formats
+
+#endif  // IMAGE_IO_BASE_OSTREAM_REF_DATA_DESTINATION_H_  // NOLINT