Client: Add fullscreen shell integration

[ChangeLog][QPA plugin] Added support for fullscreen-shell unstable v1.

The fullscreen_shell_unstable_v1 interface displays a single surface
per output and it is used for nested compositors, where each output
is rendered in a surface that is then displayed by the main
compositor.

For example weston could be the main compositor and a QML compositor
could be launched as a client using this shell integration to
display it inside weston.

Change-Id: I037679a283ff03cb4bdf4b3fed59945090ec9250
Reviewed-by: Johan Helsing <johan.helsing@qt.io>

2 files changed, 264 insertions, 0 deletions

diff --git a/src/3rdparty/protocol/fullscreen-shell-unstable-v1.xml b/src/3rdparty/protocol/fullscreen-shell-unstable-v1.xml
new file mode 100644
index 000000000..1bca7b7c7
--- /dev/null
+++ b/src/3rdparty/protocol/fullscreen-shell-unstable-v1.xml
@@ -0,0 +1,245 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="fullscreen_shell_unstable_v1">
+
+  <copyright>
+    Copyright © 2016 Yong Bakos
+    Copyright © 2015 Jason Ekstrand
+    Copyright © 2015 Jonas Ådahl
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice (including the next
+    paragraph) shall be included in all copies or substantial portions of the
+    Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+  </copyright>
+
+  <interface name="zwp_fullscreen_shell_v1" version="1">
+    <description summary="displays a single surface per output">
+      Displays a single surface per output.
+
+      This interface provides a mechanism for a single client to display
+      simple full-screen surfaces.  While there technically may be multiple
+      clients bound to this interface, only one of those clients should be
+      shown at a time.
+
+      To present a surface, the client uses either the present_surface or
+      present_surface_for_mode requests.  Presenting a surface takes effect
+      on the next wl_surface.commit.  See the individual requests for
+      details about scaling and mode switches.
+
+      The client can have at most one surface per output at any time.
+      Requesting a surface to be presented on an output that already has a
+      surface replaces the previously presented surface.  Presenting a null
+      surface removes its content and effectively disables the output.
+      Exactly what happens when an output is "disabled" is
+      compositor-specific.  The same surface may be presented on multiple
+      outputs simultaneously.
+
+      Once a surface is presented on an output, it stays on that output
+      until either the client removes it or the compositor destroys the
+      output.  This way, the client can update the output's contents by
+      simply attaching a new buffer.
+
+      Warning! The protocol described in this file is experimental and
+      backward incompatible changes may be made. Backward compatible changes
+      may be added together with the corresponding interface version bump.
+      Backward incompatible changes are done by bumping the version number in
+      the protocol and interface names and resetting the interface version.
+      Once the protocol is to be declared stable, the 'z' prefix and the
+      version number in the protocol and interface names are removed and the
+      interface version number is reset.
+    </description>
+
+    <request name="release" type="destructor">
+      <description summary="release the wl_fullscreen_shell interface">
+	Release the binding from the wl_fullscreen_shell interface.
+
+	This destroys the server-side object and frees this binding.  If
+	the client binds to wl_fullscreen_shell multiple times, it may wish
+	to free some of those bindings.
+      </description>
+    </request>
+
+    <enum name="capability">
+      <description summary="capabilities advertised by the compositor">
+	Various capabilities that can be advertised by the compositor.  They
+	are advertised one-at-a-time when the wl_fullscreen_shell interface is
+	bound.  See the wl_fullscreen_shell.capability event for more details.
+
+	ARBITRARY_MODES:
+	This is a hint to the client that indicates that the compositor is
+	capable of setting practically any mode on its outputs.  If this
+	capability is provided, wl_fullscreen_shell.present_surface_for_mode
+	will almost never fail and clients should feel free to set whatever
+	mode they like.  If the compositor does not advertise this, it may
+	still support some modes that are not advertised through wl_global.mode
+	but it is less likely.
+
+	CURSOR_PLANE:
+	This is a hint to the client that indicates that the compositor can
+	handle a cursor surface from the client without actually compositing.
+	This may be because of a hardware cursor plane or some other mechanism.
+	If the compositor does not advertise this capability then setting
+	wl_pointer.cursor may degrade performance or be ignored entirely.  If
+	CURSOR_PLANE is not advertised, it is recommended that the client draw
+	its own cursor and set wl_pointer.cursor(NULL).
+      </description>
+      <entry name="arbitrary_modes" value="1" summary="compositor is capable of almost any output mode"/>
+      <entry name="cursor_plane" value="2" summary="compositor has a separate cursor plane"/>
+    </enum>
+
+    <event name="capability">
+      <description summary="advertises a capability of the compositor">
+	Advertises a single capability of the compositor.
+
+	When the wl_fullscreen_shell interface is bound, this event is emitted
+	once for each capability advertised.  Valid capabilities are given by
+	the wl_fullscreen_shell.capability enum.  If clients want to take
+	advantage of any of these capabilities, they should use a
+	wl_display.sync request immediately after binding to ensure that they
+	receive all the capability events.
+      </description>
+      <arg name="capability" type="uint"/>
+    </event>
+
+    <enum name="present_method">
+      <description summary="different method to set the surface fullscreen">
+	Hints to indicate to the compositor how to deal with a conflict
+	between the dimensions of the surface and the dimensions of the
+	output. The compositor is free to ignore this parameter.
+      </description>
+      <entry name="default" value="0" summary="no preference, apply default policy"/>
+      <entry name="center" value="1" summary="center the surface on the output"/>
+      <entry name="zoom" value="2" summary="scale the surface, preserving aspect ratio, to the largest size that will fit on the output" />
+      <entry name="zoom_crop" value="3" summary="scale the surface, preserving aspect ratio, to fully fill the output cropping if needed" />
+      <entry name="stretch" value="4" summary="scale the surface to the size of the output ignoring aspect ratio" />
+    </enum>
+
+    <request name="present_surface">
+      <description summary="present surface for display">
+	Present a surface on the given output.
+
+	If the output is null, the compositor will present the surface on
+	whatever display (or displays) it thinks best.  In particular, this
+	may replace any or all surfaces currently presented so it should
+	not be used in combination with placing surfaces on specific
+	outputs.
+
+	The method parameter is a hint to the compositor for how the surface
+	is to be presented.  In particular, it tells the compositor how to
+	handle a size mismatch between the presented surface and the
+	output.  The compositor is free to ignore this parameter.
+
+	The "zoom", "zoom_crop", and "stretch" methods imply a scaling
+	operation on the surface.  This will override any kind of output
+	scaling, so the buffer_scale property of the surface is effectively
+	ignored.
+      </description>
+      <arg name="surface" type="object" interface="wl_surface" allow-null="true"/>
+      <arg name="method" type="uint"/>
+      <arg name="output" type="object" interface="wl_output" allow-null="true"/>
+    </request>
+
+    <request name="present_surface_for_mode">
+      <description summary="present surface for display at a particular mode">
+	Presents a surface on the given output for a particular mode.
+
+	If the current size of the output differs from that of the surface,
+	the compositor will attempt to change the size of the output to
+	match the surface.  The result of the mode-switch operation will be
+	returned via the provided wl_fullscreen_shell_mode_feedback object.
+
+	If the current output mode matches the one requested or if the
+	compositor successfully switches the mode to match the surface,
+	then the mode_successful event will be sent and the output will
+	contain the contents of the given surface.  If the compositor
+	cannot match the output size to the surface size, the mode_failed
+	will be sent and the output will contain the contents of the
+	previously presented surface (if any).  If another surface is
+	presented on the given output before either of these has a chance
+	to happen, the present_cancelled event will be sent.
+
+	Due to race conditions and other issues unknown to the client, no
+	mode-switch operation is guaranteed to succeed.  However, if the
+	mode is one advertised by wl_output.mode or if the compositor
+	advertises the ARBITRARY_MODES capability, then the client should
+	expect that the mode-switch operation will usually succeed.
+
+	If the size of the presented surface changes, the resulting output
+	is undefined.  The compositor may attempt to change the output mode
+	to compensate.  However, there is no guarantee that a suitable mode
+	will be found and the client has no way to be notified of success
+	or failure.
+
+	The framerate parameter specifies the desired framerate for the
+	output in mHz.  The compositor is free to ignore this parameter.  A
+	value of 0 indicates that the client has no preference.
+
+	If the value of wl_output.scale differs from wl_surface.buffer_scale,
+	then the compositor may choose a mode that matches either the buffer
+	size or the surface size.  In either case, the surface will fill the
+	output.
+      </description>
+      <arg name="surface" type="object" interface="wl_surface"/>
+      <arg name="output" type="object" interface="wl_output"/>
+      <arg name="framerate" type="int"/>
+      <arg name="feedback" type="new_id" interface="zwp_fullscreen_shell_mode_feedback_v1"/>
+    </request>
+
+    <enum name="error">
+      <description summary="wl_fullscreen_shell error values">
+	These errors can be emitted in response to wl_fullscreen_shell requests.
+      </description>
+      <entry name="invalid_method" value="0" summary="present_method is not known"/>
+    </enum>
+  </interface>
+
+  <interface name="zwp_fullscreen_shell_mode_feedback_v1" version="1">
+    <event name="mode_successful">
+      <description summary="mode switch succeeded">
+	This event indicates that the attempted mode switch operation was
+	successful.  A surface of the size requested in the mode switch
+	will fill the output without scaling.
+
+	Upon receiving this event, the client should destroy the
+	wl_fullscreen_shell_mode_feedback object.
+      </description>
+    </event>
+
+    <event name="mode_failed">
+      <description summary="mode switch failed">
+	This event indicates that the attempted mode switch operation
+	failed.  This may be because the requested output mode is not
+	possible or it may mean that the compositor does not want to allow it.
+
+	Upon receiving this event, the client should destroy the
+	wl_fullscreen_shell_mode_feedback object.
+      </description>
+    </event>
+
+    <event name="present_cancelled">
+      <description summary="mode switch cancelled">
+	This event indicates that the attempted mode switch operation was
+	cancelled.  Most likely this is because the client requested a
+	second mode switch before the first one completed.
+
+	Upon receiving this event, the client should destroy the
+	wl_fullscreen_shell_mode_feedback object.
+      </description>
+    </event>
+  </interface>
+
+</protocol>
diff --git a/src/3rdparty/protocol/qt_attribution.json b/src/3rdparty/protocol/qt_attribution.json
index e5bf91e10..615e95a9f 100644
--- a/src/3rdparty/protocol/qt_attribution.json
+++ b/src/3rdparty/protocol/qt_attribution.json
@@ -1,5 +1,24 @@
 [
     {
+        "Id": "wayland-fullscreen-protocol",
+        "Name": "Wayland Fullscreen Shell Protocol",
+        "QDocModule": "qtwaylandcompositor",
+        "QtUsage": "Used in the Qt Wayland platform plugin.",
+        "Files": "fullscreen-shell-unstable-v1.xml",
+
+        "Description": "A Wayland shell for displaying a single surface per output",
+        "Homepage": "https://wayland.freedesktop.org",
+        "Version": "unstable v1",
+        "DownloadLocation": "https://cgit.freedesktop.org/wayland/wayland-protocols",
+        "LicenseId": "MIT",
+        "License": "MIT License",
+        "LicenseFile": "MIT_LICENSE.txt",
+        "Copyright": "Copyright © 2016 Yong Bakos
+Copyright © 2015 Jason Ekstrand
+Copyright © 2015 Jonas Ådahl"
+    },
+
+    {
         "Id": "wayland-protocol",
         "Name": "Wayland Protocol",
         "QDocModule": "qtwaylandcompositor",