New file transfer API

There were several shortcomings to the existing file transfer API,
particularly in terms of monitoring ongoing file transfers. The major
issue is that spice_main_file_copy_async() allows you to pass an array
of files, but the progress callback does not provide a way to
identify which file the callback is associated with. This makes it
nearly impossible for an application to monitor file transfers.

In addition, the SpiceDisplay widget automatically handles drag-and-drop
actions on the widget, and initiates file transfers without allowing the
application to specify a progress callback. So there's no way for an app
to monitor file transfers that are initiated via drag and drop.

http://lists.freedesktop.org/archives/spice-devel/2015-September/021931.html
has a more detailed explanation of the issues.

This change doesn't break the existing API, but adds some new API that
will allow an application to monitor file transfer progress, even for
transfers that are initiated within spice-gtk itself.

- A new public SpiceFileTransferTask object is added.
- The SpiceMainChannel object gains a "new-file-transfer" signal that is
  emitted whenever a new file transfer is initiated. The
  SpiceFileTransferTask object is passed to the signal handler.
- The application can retain this object and monitor its 'progress'
  property to be notified when the progress of the file transfer
  changes. The SpiceFileTransferTask::finished signal indicates when the
  given file transfer has completed. The application can also cancel the
  file transfer by calling the _cancel() method.

The 'spicy' test application has been updated to use this new API and
display a simple dialog showing the progress of individual files.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/spice-glib-sym-file b/src/spice-glib-sym-file
index 1d62716..3817a46 100644
--- a/src/spice-glib-sym-file
+++ b/src/spice-glib-sym-file
@@ -20,6 +20,11 @@ spice_client_error_quark
 spice_cursor_channel_get_type
 spice_display_channel_get_type
 spice_display_get_primary
+spice_file_transfer_task_cancel
+spice_file_transfer_task_get_filename
+spice_file_transfer_task_get_finished
+spice_file_transfer_task_get_progress
+spice_file_transfer_task_get_type
 spice_get_option_group
 spice_g_signal_connect_object
 spice_inputs_button_press