Add basic support for loading ControlLook add-ons

app_server just passes the add-on path around.

Maybe we should make sure the add-on can be loaded when setting it.

Change-Id: I3acd3299782a22c1666bd5435dbf3d8053e359fa
Reviewed-on: https://review.haiku-os.org/c/1430
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

headers/os/interface/ControlLook.h

@@ -418,6 +418,8 @@ protected:
 
 extern BControlLook* be_control_look;
 
+extern "C" _EXPORT BControlLook *instantiate_control_look(image_id id);
+
 
 } // namespace BPrivate
 

headers/private/app/ServerProtocol.h

@@ -189,6 +189,8 @@ enum {
 	AS_R5_SET_DECORATOR,
 	AS_COUNT_DECORATORS,
 	AS_GET_DECORATOR_NAME,
+	AS_SET_CONTROL_LOOK,
+	AS_GET_CONTROL_LOOK,
 
 	AS_COUNT_WORKSPACES,
 	AS_CURRENT_WORKSPACE,

headers/private/interface/InterfacePrivate.h

@@ -26,6 +26,9 @@ int32		get_bytes_per_row(color_space colorSpace, int32 width);
 void		get_workspaces_layout(uint32* _columns, uint32* _rows);
 void		set_workspaces_layout(uint32 columns, uint32 rows);
 
+bool		get_control_look(BString& path);
+status_t	set_control_look(const BString& path);
+
 }	// namespace BPrivate
 
 

src/kits/interface/ControlLook.cpp

@@ -89,9 +89,7 @@ void BControlLook::_ReservedControlLook9() {}
 void BControlLook::_ReservedControlLook10() {}
 
 
-// NOTE: May come from a add-on in the future. Initialized in
-// InterfaceDefs.cpp
+// Initialized in InterfaceDefs.cpp
 BControlLook* be_control_look = NULL;
 
-
 } // namespace BPrivate

src/kits/interface/InterfaceDefs.cpp

@@ -162,6 +162,8 @@ static const char* kColorNames[kColorWhichCount] = {
 	NULL
 };
 
+static image_id sControlLookAddon = -1;
+
 
 namespace BPrivate {
 
@@ -1286,8 +1288,24 @@ _init_interface_kit_()
 	if (be_clipboard == NULL)
 		be_clipboard = new BClipboard(NULL);
 
-	// TODO: Could support different themes here in the future.
-	be_control_look = new HaikuControlLook();
+	BString path;
+	if (get_control_look(path) && path.Length() > 0) {
+		BControlLook* (*instantiate)(image_id);
+
+		sControlLookAddon = load_add_on(path.String());
+		if (sControlLookAddon >= 0
+			&& get_image_symbol(sControlLookAddon,
+				"instantiate_control_look",
+				B_SYMBOL_TYPE_TEXT, (void **)&instantiate) == B_OK) {
+			be_control_look = instantiate(sControlLookAddon);
+			if (be_control_look == NULL) {
+				unload_add_on(sControlLookAddon);
+				sControlLookAddon = -1;
+			}
+		}
+	}
+	if (be_control_look == NULL)
+		be_control_look = new HaikuControlLook();
 
 	_init_global_fonts_();
 
@@ -1325,6 +1343,13 @@ _fini_interface_kit_()
 	delete be_control_look;
 	be_control_look = NULL;
 
+	// Note: if we ever want to support live switching, we cannot just unload
+	// the old one since some thread might still be in a method of the object.
+	// maybe locking/unlocking all loopers around would ensure proper exit.
+	if (sControlLookAddon >= 0)
+		unload_add_on(sControlLookAddon);
+	sControlLookAddon = -1;
+
 	// TODO: Anything else?
 
 	return B_OK;
@@ -1394,6 +1419,46 @@ preview_decorator(const BString& path, BWindow* window)
 }
 
 
+/*!	\brief queries the server for the current ControlLook path
+	\param path BString into which to store current ControlLook's add-on path
+	\return boolean true/false
+*/
+bool
+get_control_look(BString& path)
+{
+	BPrivate::AppServerLink link;
+	link.StartMessage(AS_GET_CONTROL_LOOK);
+
+	int32 code;
+	if (link.FlushWithReply(code) != B_OK || code != B_OK)
+		return false;
+
+	return link.ReadString(path) == B_OK;
+}
+
+
+/*!	\brief Private function which sets the ControlLook for the system.
+	\param BString with the ControlLook add-on path to set
+
+	Will return detailed error status via status_t
+*/
+status_t
+set_control_look(const BString& path)
+{
+	BPrivate::AppServerLink link;
+
+	link.StartMessage(AS_SET_CONTROL_LOOK);
+
+	link.AttachString(path.String());
+
+	status_t error = B_OK;
+	if (link.FlushWithReply(error) != B_OK)
+		return B_ERROR;
+
+	return error;
+}
+
+
 status_t
 get_application_order(int32 workspace, team_id** _applications,
 	int32* _count)

src/servers/app/DesktopSettings.cpp

@@ -293,6 +293,11 @@ DesktopSettingsPrivate::_Load()
 				gSubpixelOrderingRGB = subpixelOrdering;
 			}
 
+			const char* controlLook;
+			if (settings.FindString("control look", &controlLook) == B_OK) {
+				fControlLook = controlLook;
+			}
+
 			// colors
 			for (int32 i = 0; i < kColorWhichCount; i++) {
 				char colorName[12];
@@ -442,6 +447,8 @@ DesktopSettingsPrivate::Save(uint32 mask)
 			settings.AddInt8("subpixel average weight", gSubpixelAverageWeight);
 			settings.AddBool("subpixel ordering", gSubpixelOrderingRGB);
 
+			settings.AddString("control look", fControlLook);
+
 			for (int32 i = 0; i < kColorWhichCount; i++) {
 				char colorName[12];
 				snprintf(colorName, sizeof(colorName), "color%" B_PRId32,
@@ -785,6 +792,21 @@ DesktopSettingsPrivate::IsSubpixelOrderingRegular() const
 }
 
 
+status_t
+DesktopSettingsPrivate::SetControlLook(const char* path)
+{
+	fControlLook = path;
+	return Save(kAppearanceSettings);
+}
+
+
+const BString&
+DesktopSettingsPrivate::ControlLook() const
+{
+	return fControlLook;
+}
+
+
 void
 DesktopSettingsPrivate::_ValidateWorkspacesLayout(int32& columns,
 	int32& rows) const
@@ -939,6 +961,13 @@ DesktopSettings::IsSubpixelOrderingRegular() const
 	return fSettings->IsSubpixelOrderingRegular();
 }
 
+
+const BString&
+DesktopSettings::ControlLook() const
+{
+	return fSettings->ControlLook();
+}
+
 //	#pragma mark - write access
 
 
@@ -1059,3 +1088,10 @@ LockedDesktopSettings::SetSubpixelOrderingRegular(bool subpixelOrdering)
 	fSettings->SetSubpixelOrderingRegular(subpixelOrdering);
 }
 
+
+status_t
+LockedDesktopSettings::SetControlLook(const char* path)
+{
+	return fSettings->SetControlLook(path);
+}
+

src/servers/app/DesktopSettings.h

@@ -76,6 +76,8 @@ public:
 			uint8				SubpixelAverageWeight() const;
 			bool				IsSubpixelOrderingRegular() const;
 
+			const BString&		ControlLook() const;
+
 protected:
 			DesktopSettingsPrivate*	fSettings;
 };
@@ -109,6 +111,8 @@ public:
 			void				SetSubpixelOrderingRegular(
 									bool subpixelOrdering);
 
+			status_t			SetControlLook(const char* path);
+
 private:
 			Desktop*			fDesktop;
 };

src/servers/app/DesktopSettingsPrivate.h

@@ -92,6 +92,9 @@ public:
 									bool subpixelOrdering);
 			bool				IsSubpixelOrderingRegular() const;
 
+			status_t			SetControlLook(const char* path);
+			const BString&		ControlLook() const;
+
 private:
 			void				_SetDefaults();
 			status_t			_Load();
@@ -112,6 +115,7 @@ private:
 			int32				fWorkspacesColumns;
 			int32				fWorkspacesRows;
 			BMessage			fWorkspaceMessages[kMaxWorkspaces];
+			BString				fControlLook;
 
 			server_read_only_memory& fShared;
 };

src/servers/app/ServerApp.cpp

@@ -697,6 +697,39 @@ ServerApp::_DispatchMessage(int32 code, BPrivate::LinkReceiver& link)
 			break;
 		}
 
+		case AS_SET_CONTROL_LOOK:
+		{
+			STRACE(("ServerApp %s: Set ControlLook\n", Signature()));
+
+			BString path;
+			status_t error = B_ERROR;
+			if (link.ReadString(path) == B_OK) {
+				LockedDesktopSettings settings(fDesktop);
+				error = settings.SetControlLook(path.String());
+			}
+
+			fLink.StartMessage(error);
+			fLink.Flush();
+			break;
+		}
+
+		case AS_GET_CONTROL_LOOK:
+		{
+			STRACE(("ServerApp %s: Get ControlLook\n", Signature()));
+
+			if (fDesktop->LockSingleWindow()) {
+				DesktopSettings settings(fDesktop);
+
+				fLink.StartMessage(B_OK);
+				fLink.AttachString(settings.ControlLook().String());
+				fDesktop->UnlockSingleWindow();
+			} else
+				fLink.StartMessage(B_ERROR);
+
+			fLink.Flush();
+			break;
+		}
+
 		case AS_CREATE_BITMAP:
 		{
 			STRACE(("ServerApp %s: Received BBitmap creation request\n",