typedef struct {
	int x;
	int y;
	int width;
	int height;
} GdkRectangle;
enum {
	GTK_POS_LEFT, GTK_POS_RIGHT, GTK_POS_TOP, GTK_POS_BOTTOM,
	DRAG_OPERATION_NONE, DRAG_OPERATION_REORDER, DRAG_OPERATION_DETACH
};
typedef struct {
	void *parent;
} GtkWidget;
typedef struct {
	GtkWidget *tab_label;
	int pack;
	GdkRectangle requisition, allocation;
} GtkNotebookPage;
typedef struct {
	GtkNotebookPage *cur_page;
	int homogeneous:1;
} GtkNotebook;
typedef struct {
	int operation;
	int x;
	GtkNotebookPage *detached_tab;
} GtkNotebookPrivate;
gtk_notebook_calculate_tabs_allocation()
{
	GtkNotebook *notebook;
	void **children;
	void *last_child;
	int *remaining_space;
	int *expanded_tabs;
	GtkNotebookPrivate *priv;
	GtkNotebookPage *page;
	int allocate_at_bottom;
	int tab_overlap;
	int tab_pos;
	int tab_extra_space;
	int left_x;
	int right_x;
	int top_y;
	int anchor;
	int xthickness;
	int ythickness;
	int gap_left;
	int packing_changed;
	GdkRectangle child_allocation;
	while (*children && *children != last_child) {
		if (page->tab_label->parent != notebook)
			continue;
		if (*expanded_tabs && notebook->homogeneous)
			tab_extra_space = *remaining_space / *expanded_tabs;
		switch (tab_pos) {
		case GTK_POS_TOP:
		case GTK_POS_BOTTOM:
			child_allocation.width =
			    page->requisition.width + tab_overlap +
			    tab_extra_space;
			if (gap_left && packing_changed) {
				if (allocate_at_bottom
&&
notebook->cur_page->pack
					    && right_x > anchor)
						anchor -=
						    notebook->cur_page->
						    allocation.width;
			} else {
				if (allocate_at_bottom)
					anchor -= child_allocation.width;
				if (priv->operation == DRAG_OPERATION_REORDER
				    && page->pack == notebook->cur_page->pack)
					if (!allocate_at_bottom
					    && left_x >= anchor
					    && left_x <=
					    anchor + child_allocation.width / 2)
						anchor +=
						    notebook->cur_page->
						    allocation.width -
						    tab_overlap;
				child_allocation.x = anchor;
}
		case GTK_POS_LEFT:
		case GTK_POS_RIGHT:
			child_allocation.height =
			    page->requisition.height + tab_overlap +
			    tab_extra_space;
			if (packing_changed)
				priv->x = child_allocation.x;
				if (priv->operation == DRAG_OPERATION_REORDER
				    && page->pack == notebook->cur_page->pack)
					if (!allocate_at_bottom
					    && top_y >= anchor
					    && top_y <=
					    anchor +
					    child_allocation.height / 2)
						anchor +=
						    notebook->cur_page->
						    allocation.height -
						    tab_overlap;
		}
		if ((page == priv->detached_tab
		     && priv->operation == DRAG_OPERATION_DETACH)
		    || (page == notebook->cur_page
			&& priv->operation == DRAG_OPERATION_REORDER))
			page->allocation.x = 0;
		if (page != notebook->cur_page)
			switch (tab_pos) {
			case GTK_POS_TOP:
				page->allocation.y = ythickness;
			case GTK_POS_BOTTOM:
				page->allocation.height =
				    page->allocation.height 
;
			case GTK_POS_LEFT:
				page->allocation.x = xthickness;
			case GTK_POS_RIGHT:
				page->allocation.width =
				    page->allocation.width ;
			}
		switch (tab_pos) {
		case GTK_POS_TOP:
		case GTK_POS_BOTTOM:
			if (priv->operation != DRAG_OPERATION_REORDER
			    || priv->operation == DRAG_OPERATION_REORDER
			    && page != notebook->cur_page)
				if (!allocate_at_bottom)
					anchor +=
					    child_allocation.width -
					    tab_overlap;
		case GTK_POS_LEFT:
		case GTK_POS_RIGHT:
			if (priv->operation != DRAG_OPERATION_REORDER
			    || priv->operation == DRAG_OPERATION_REORDER
			    && page != notebook->cur_page)
				if (priv->operation == DRAG_OPERATION_REORDER)
					if (page->pack ==
					    notebook->cur_page->pack
					    && !allocate_at_bottom
					    && top_y >=
					    anchor + child_allocation.height / 2
					    && top_y <=
					    anchor + child_allocation.height)
						anchor +=
						    notebook->cur_page->
						    allocation.height -
						    tab_overlap;
		}
		if (page->tab_label)
			IA__gtk_widget_set_child_visible(page->tab_label, 1);
	}
}