Add XAppGpuOffloadHelper.

By using switcheroo-control, this will provide broader support for
gpu offloading than relying on magic Ubuntu files.

If switcheroo isn't available, xapp_util_gpu_offload_supported() is
used like before, with default environment variables.

docs/xapp-docs.xml

@@ -18,6 +18,7 @@
  <title>API reference</title>
  <xi:include href="xml/xapp-favorites.xml"/>
  <xi:include href="xml/xapp-gtk-window.xml"/>
+ <xi:include href="xml/xapp-gpu-offload-helper.xml"/>
  <xi:include href="xml/xapp-icon-chooser-button.xml"/>
  <xi:include href="xml/xapp-icon-chooser-dialog.xml"/>
  <xi:include href="xml/xapp-kbd-layout-controller.xml"/>

libxapp/meson.build

@@ -30,6 +30,7 @@ xapp_debug = [
 xapp_headers = [
  'xapp-favorites.h',
  'xapp-gtk-window.h',
+ 'xapp-gpu-offload-helper.h',
  'xapp-icon-chooser-button.h',
  'xapp-icon-chooser-dialog.h',
  'xapp-monitor-blanker.h',
@@ -46,6 +47,7 @@ xapp_sources = [
  'xapp-favorites.c',
  'xapp-glade-catalog.c',
  'xapp-gtk-window.c',
+ 'xapp-gpu-offload-helper.c',
  'xapp-icon-chooser-button.c',
  'xapp-icon-chooser-dialog.c',
  'xapp-monitor-blanker.c',
@@ -58,6 +60,15 @@ xapp_sources = [
  'xapp-visibility-group.c'
 ]
 
+switcheroo_sources = gnome.gdbus_codegen(
+ 'xapp-switcheroo-interface',
+ sources: 'net.hadess.SwitcherooControl.xml',
+ interface_prefix: 'net.hadess',
+ namespace: 'XApp'
+)
+
+xapp_sources += switcheroo_sources
+
 if not app_lib_only
  libdeps += dependency('libgnomekbdui', required: true)
  xapp_headers += 'xapp-kbd-layout-controller.h'

libxapp/net.hadess.SwitcherooControl.xml

@@ -0,0 +1,46 @@
+<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
+"http:https://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
+
+<node>
+
+ <!--
+ net.hadess.SwitcherooControl:
+ @short_description: D-Bus proxy to access dual-GPU controls.
+
+ After checking the availability of two switchable GPUs in the machine,
+ check the value of net.hadess.SwitcherooControl.HasDualGpu to see
+ if running applications on the discrete GPU should be offered.
+
+ The object path will be "/net/hadess/SwitcherooControl".
+ -->
+ <interface name="net.hadess.SwitcherooControl">
+ <!--
+ HasDualGpu:
+
+ Whether two switchable GPUs are present on the system. This property
+ has been obsoleted in favour of the "NumGPUs" property.
+ -->
+ <property name="HasDualGpu" type="b" access="read"/>
+
+ <!--
+ NumGPUs:
+
+ The number of GPUs available on the system. Note that while having no
+ GPUs is unlikely, consumers of this API should probably not throw errors
+ if that were the case.
+ -->
+ <property name="NumGPUs" type="u" access="read"/>
+
+ <!--
+ GPUs:
+
+ An array of key-pair values representing each GPU. The key named "Name" (s)
+ will contain a user-facing name for the GPU, the "Environment" (as) key will
+ contain an array of even number of strings, each being an environment
+ variable to set to use the GPU, followed by its value, the "Default" (b) key
+ will tag the default (usually integrated) GPU.
+ -->
+ <property name="GPUs" type="aa{sv}" access="read"/>
+
+ </interface>
+</node>

libxapp/xapp-debug.c

@@ -39,6 +39,7 @@ static GDebugKey keys[] = {
  { "SnWatcher", XAPP_DEBUG_SN_WATCHER },
  { "GtkModule", XAPP_DEBUG_MODULE},
  { "VisibilityGroup", XAPP_DEBUG_VISIBILITY_GROUP},
+ { "GpuOffload", XAPP_DEBUG_GPU_OFFLOAD},
  { 0, }
 };
 
@@ -61,6 +62,8 @@ debug_flag_to_string (DebugFlags flag)
  return "GtkModule";
  case XAPP_DEBUG_VISIBILITY_GROUP:
  return "VisibilityGroup";
+ case XAPP_DEBUG_GPU_OFFLOAD:
+ return "GpuOffload";
  }
  return "";
 }

libxapp/xapp-debug.h

@@ -40,7 +40,8 @@ typedef enum
  XAPP_DEBUG_STATUS_ICON = 1 << 4,
  XAPP_DEBUG_SN_WATCHER = 1 << 5,
  XAPP_DEBUG_MODULE = 1 << 6,
- XAPP_DEBUG_VISIBILITY_GROUP = 1 << 7
+ XAPP_DEBUG_VISIBILITY_GROUP = 1 << 7,
+ XAPP_DEBUG_GPU_OFFLOAD = 1 << 8
 } DebugFlags;
 
 void xapp_debug_set_flags (DebugFlags flags);