Also make clipboard_claim() a vfunc so backends can override it.
Because the whole operation a vfunc, backends have the option of adding
code before the actual claim is done and potentially even fail or do
something after the successful claim.
Instead of having just one function that has the gtype and mime type as
out arguments, have 3 functions: 1 that finds any match, 1 that finds a
GType match and one for a mime type match.
This makes the API way more convenient to use.
This requires implementing a "pipe" so we can have 2 streams running:
contentprovider => serializer => outputstream
inputstream => deserializer => reader
And the pipe shoves the data from the outputstream into the inputstream.
GdkContentProvider is the object that represents local data in the
clipboard.
This patch only introduces the object and adds the clipboard properties,
it does not yet provide a way for the actual implementations to access
it.
The only access that is implemented is the local shortcut GValue access.
(1) Try all passed in formats in order if one of them fails.
(2) Don't blindly accept all formats, make sure they are mime types
(3) Add a bunch of special non-mime types that plug converters to
get to mime types
This allows us not just to pass any mime type to the read function, but
it also makes it possible to pass multiple mime types and the clipboard
can then try them in order until it finds a supported one.
This is so far not implemented though.
Turns out, way too many async operations are implemented by running the
sync operation in a thread. The easiest solution is to support that is
to use a GAsyncQueue for the buffers and deadlock if called from the
main thread.
(1) Turn X11 clipboard event handling into a regular filter function
(2) Maintain a timestamp in the clipboard, so we can pass it when
querying selections.
No idea why it's here, the hash table can store any kind of data,
there's no reason why it wouldn't be able to store an old X string type.
Might be a holdout from the old days, when strings were handled in
a special way (stored directly in the clipboard?).
https://bugzilla.gnome.org/show_bug.cgi?id=786509
This prevents GTK from throwing a bunch of warnings when it tries
to get drag source window -> screen of that window -> ipc widget for that screen,
and then tries to attach a signal handler to that widget.
Specifically, this happens when we get a DnD move from another
application.
https://bugzilla.gnome.org/show_bug.cgi?id=786509
1) Ensure that any DELETE requests from the target are sent to GDK, even if
both the source and the target are in the same process and it
is therefore possible to use a shortcut and call the handler directly
in GTK layer
2) Ensure that target GDK doesn't do anything when GTK asks it to send
a DELETE request, just report back immediately (the code up the stack
does not check for successfullness when request is DELETE, so not giving
it any data is OK).
The source code already synthesizes a DELETE request, so that side is
also taken care of.
https://bugzilla.gnome.org/show_bug.cgi?id=786509
We need to know the target atom value to know when we need to
do something with side-effects (since side-effects are expressed via
special target values). Previously, the code side-stepped that by looking
at the data type (which was rather unique for the one side-effect
target that we supported, signalled by the TARGETS target),
but for the DELETE target that seems to be no longer an option, hence the new
field to carry this information past the convert_selection() routine.
This prevents GDK from throwing a warning when trying to convert
a DELETE target, which has no format or data objects set.
The side-effects for the DELETE target happen earlier, in GTK layer.
By the point it gets to change_property(), it's a no-op.
https://bugzilla.gnome.org/show_bug.cgi?id=786509
To do that, run the message loop for one second or until the side-effect
of running the selection request handler is achieved (as opposed to
running it until the event is no longer queued).
The disavantage of this method is that if the event handling is
somehow missed (due to a variety of reasons - after all, it's not
a straight path from an event being queued to property_change()
being called), this will loop for one second. Since we do process
events during that time, this will not hang the application, but
might still restrict some of the functionality.
https://bugzilla.gnome.org/show_bug.cgi?id=786509
Handle WM_CANCELMODE and do nothing in response to it when DnD is
active. Otherwise pass it to DefWindowProc, which will call ReleaseCapture()
on our behalf.
This prevents us from losing mouse capture when alt-tabbing during DnD
(this includes the feature of Windows Explorer where dragging stuff over
a window button in the taskbar causes that window to receive focus, i.e.
keyboardless alt-tabbing).
https://bugzilla.gnome.org/show_bug.cgi?id=786509
Without this patch layered windows are only updated when they are moved
by the user or then their contents changes. This patch adds opacity
changes to the list of things that make GDK update a window. Without this
windows that don't redraw and are not moved by the used (DnD drag indicator
windows, for example) don't change their opacity.
(This commit is cherry-picked from the gtk-3-22 branch)
https://bugzilla.gnome.org/show_bug.cgi?id=786509
Massive changes to OLE2 DnD protocol, which was completely broken before:
* Keep GdkDragContext and OLE2 objects separate (don't ref/unref them
together, don't necessarily create them together).
* Keep IDataObject formats in the object itself, not in a global variable.
* Fix getdata() to look up the request target in its format list, not in the
global hash table
* Create target GdkDragContext on each drag_enter, destroy it on drag_leave,
whereas IDropTarget is created when a window becomes a drag destination
and is re-used indefinitely.
* Query the source IDataObject for its supported types, cache them in the
target (!) context. This is how GTK+ works, honestly.
* Remember current_src_object when we initiate a drag, to be able
to detect later on that the data object is ours and use a
shortcut when querying targets
* Make sure GDK_DRAG_MOTION is only sent when something changes
* Support GTK drag cursors
* Ensure that exotic GTK clipboard formats are registered
(but try to avoid registering formats that can't be used between applications).
* Don't enumerate internal formats
* Ensure that DnD indicator window can't accept drags or receive any kind of input
(use WS_EX_TRANSPARENT).
* Remove unneeded indentation in _gdk_win32_dnd_do_dragdrop()
* Fix indentation in gdk_win32_drag_context_drop_finish()
* Remove obsolete comments in _gdk_win32_window_register_dnd()
* Check for DnD in progress when processing WM_KILLFOCUS, don't emit a grab
break event in such cases (this allows alt-tabbing while DnD is in progress,
though there may be lingering issues with focus after dropping...)
* Support Shell ID List -> text/uri-list conversion, now it's possible
to drop files (dragged from Explorer) on GTK+ applications
* Explicitly use RegisterClipboardFormatA() when we know that the string
is not in unicode. Otherwise explicitly use RegisterClipboardFormatW()
with a UTF8->UTF16 converted string
* Fix _gdk_win32_display_get_selection_owner() to correctly bail
when selection owner HWND is NULL (looking up GdkWindow for NULL
HWND always succeeds and returns the root window - not the intended
effect)
* More logging
* Send DROP_FINISHED event after DnD loop ends
* Send STATUS event on feedback
* Move GetKeyboardState() and related code into _gdk_win32_window_drag_begin(),
so that it's closer to the point where last_pt and start_pt are set
* Use & 0x80 to check for the key being pressed. Windows will set low-order bit
to 1 for all mouse buttons to indicate that they are toggled, so simply
checking for the value not being 0 is not enough anymore.
This is probably a new thing in modern W32 that didn't exist before
(OLE2 DnD code is old).
* Fixed (hopefully) and simplified HiDPI parts of the code.
Also adds managed DnD implementation for W32 GDK backend (for both
OLE2 and LOCAL protocols). Mostly a copy of the X11 backend code, but
there are some minor differences:
* doesn't use drag_window field in GdkDragContext,
uses the one in GdkWin32DragContext exclusively
* subtracts hotspot offset from the window coordinates when showing
the dragback animation
* tries to consistently support scaling and caches the scale
in the context
* Some keynav code is removed (places where grabbing/ungrabbing should
happen is marked with TODOs), and the rest is probably inert.
Also significantly changes the way selection (and clipboard) is handled
(as MSDN rightly notes, the handling for DnD and Clipboard
formats is virtually the same, so it makes sense to handle
both with the same code):
* Don't spam GDK_OWNER_CHANGE, send them only when owner
actually changes
* Open clipboard when our process becomes the clipboard owner
(we are doing it anyway, to empty the clipboard and *become* the owner),
and then don't close it until a scheduled selection request event
(with TARGETS target) is received. Process that event by announcing
all of our supported formats (by that time add_targets() should have
been called up the stack, thus the formats are known; just in case,
add_targets() will also schedule a selection request, if one isn't
scheduled already, so that late-coming formats can still be announced).
* Allow clipboard opening for selection_convert() to be delayed if it
fails initially.
* The last two points above should fix all the bugs about GTK+ rising
too much ruckus over OpenClipboard() failures, as owner change
*is allowed* to fail (though not all callers currently handle
that case), and selection_convert() is asynchronous to begin with.
Still, this is somewhat risky, as there's a possibility that the
code will work in unexpected ways and the clipboard will remain open.
There's now logging to track the clipboard being opened and closed,
and a number of failsafes that try to ensure that it isn't kept open
for no reason.
* Added copious notes on the way clipboard works on X11, Windows and GDK-W32,
also removed old comments in DnD implementation, replaced some of them
with the new ones
* A lot of crufty module-global variables are stuffed into a singleton
object, GdkWin32Selection. It's technically possible to make it a
sub-object of the Display object (the way Wayland backend does),
but since Display object on W32 is a singleton anyway... why bother?
* Fixed the send_change_events() a bit (was slightly broken in one of the
previous iterations)
* Ensure that there's no confusion between selection conversion (an artifact
term from X11) and selection transmutation (changing the data to be W32-compatible)
* Put all the transmutation code and format-target-matching code into gdkselection-win32.c,
now this code isn't spread across multiple files.
* Consequently, moved some code away from gdkproperty-win32.c and gdkdnd-win32.c
* Extensive format transmutation checks for OLE2 DnD and clipboard.
We now keep track of which format mappings are for transmutations,
and which aren't (for example, when formats are passed as-is, or when
a registered name is just an alias)
* Put transmutation code into separate functions
* Ensure that drop target keeps a format->target map for supported formats,
this is useful when selection_convert() is called, as it only receives a
single target and no hints on the format from which the data should
be transmuted into this target.
* Add clear_targets() on W32, to de called by GTK
* Use g_set_object() instead of g_ref_object() where it is allowed.
* Fix indentation (and convert tabs to spaces), remove unused variables
(This commit is cherry-picked from the gtk-3-22 branch)
https://bugzilla.gnome.org/show_bug.cgi?id=786509
