[goffice] Canvas: fix cairo save imbalances.

[Morten Welinder <mortenw src gnome org>]

commit 1fde9d4cdd4729c888ec3b90d4ad8935ac73a826
Author: Morten Welinder <terra gnome org>
Date:   Mon Mar 25 11:32:50 2013 -0400

    Canvas: fix cairo save imbalances.

 ChangeLog                     |    5 +++++
 goffice/canvas/goc-ellipse.c  |    9 +++++++--
 goffice/canvas/goc-item.c     |    1 +
 goffice/canvas/goc-path.c     |    8 ++++++--
 goffice/canvas/goc-polygon.c  |    9 +++++++--
 goffice/canvas/goc-polyline.c |   12 ++++++++----
 6 files changed, 34 insertions(+), 10 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 7301395..9a2bcd0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-03-25  Morten Welinder  <terra gnome org>
+
+       * goffice/canvas/goc-polyline.c (goc_polyline_draw): Fix cairo
+       save stack imbalance.
+
 2013-03-23  Morten Welinder  <terra gnome org>
 
        * goffice/canvas/goc-item.c (goc_item_get_style_context): New
diff --git a/goffice/canvas/goc-ellipse.c b/goffice/canvas/goc-ellipse.c
index c79a4bd..f962961 100644
--- a/goffice/canvas/goc-ellipse.c
+++ b/goffice/canvas/goc-ellipse.c
@@ -215,18 +215,23 @@ static void
 goc_ellipse_draw (GocItem const *item, cairo_t *cr)
 {
        gboolean scale_line_width = goc_styled_item_get_scale_line_width (GOC_STYLED_ITEM (item));
+       gboolean needs_restore;
+
        cairo_save(cr);
+       needs_restore = TRUE;
        if (goc_ellipse_prepare_draw (item, cr, 1)) {
                go_styled_object_fill (GO_STYLED_OBJECT (item), cr, TRUE);
-               if (!scale_line_width)
+               if (!scale_line_width) {
                        cairo_restore (cr);
+                       needs_restore = FALSE;
+               }
                if (go_styled_object_set_cairo_line (GO_STYLED_OBJECT (item), cr)) {
                        cairo_stroke (cr);
                } else {
                        cairo_new_path (cr);
                }
        }
-       if (scale_line_width)
+       if (needs_restore)
                cairo_restore(cr);
 }
 
diff --git a/goffice/canvas/goc-item.c b/goffice/canvas/goc-item.c
index 367db02..129fa7d 100644
--- a/goffice/canvas/goc-item.c
+++ b/goffice/canvas/goc-item.c
@@ -859,6 +859,7 @@ goc_item_get_style_context (const GocItem *item)
                GtkWidgetPath *path;
 
                path = gtk_widget_path_new ();
+               gtk_widget_path_append_type (path, GOC_TYPE_CANVAS);
                gtk_widget_path_append_type (path,
                                             G_TYPE_FROM_INSTANCE (item));
 
diff --git a/goffice/canvas/goc-path.c b/goffice/canvas/goc-path.c
index 268dbc6..3a95f0f 100644
--- a/goffice/canvas/goc-path.c
+++ b/goffice/canvas/goc-path.c
@@ -202,21 +202,25 @@ goc_path_draw (GocItem const *item, cairo_t *cr)
 {
        GocPath *path = GOC_PATH (item);
        gboolean scale_line_width = goc_styled_item_get_scale_line_width (GOC_STYLED_ITEM (item));
+       gboolean needs_restore;
 
        cairo_save(cr);
+       needs_restore = TRUE;
        cairo_set_fill_rule (cr, path->fill_rule? CAIRO_FILL_RULE_EVEN_ODD: CAIRO_FILL_RULE_WINDING);
        if (goc_path_prepare_draw (item, cr, 1)) {
                if (path->closed)
                        go_styled_object_fill (GO_STYLED_OBJECT (item), cr, TRUE);
-               if (!scale_line_width)
+               if (!scale_line_width) {
                        cairo_restore (cr);
+                       needs_restore = FALSE;
+               }
                if (go_styled_object_set_cairo_line (GO_STYLED_OBJECT (item), cr)) {
                        cairo_stroke (cr);
                } else {
                        cairo_new_path (cr);
                }
        }
-       if (scale_line_width)
+       if (needs_restore)
                cairo_restore(cr);
 }
 
diff --git a/goffice/canvas/goc-polygon.c b/goffice/canvas/goc-polygon.c
index 7e0b2a0..69637bb 100644
--- a/goffice/canvas/goc-polygon.c
+++ b/goffice/canvas/goc-polygon.c
@@ -294,19 +294,24 @@ static void
 goc_polygon_draw (GocItem const *item, cairo_t *cr)
 {
        gboolean scale_line_width = goc_styled_item_get_scale_line_width (GOC_STYLED_ITEM (item));
+       gboolean needs_restore;
+
        cairo_save (cr);
+       needs_restore = TRUE;
        _goc_item_transform (item, cr, TRUE);
        if (goc_polygon_prepare_path (item, cr, 1)) {
                go_styled_object_fill (GO_STYLED_OBJECT (item), cr, TRUE);
 
-               if (!scale_line_width)
+               if (!scale_line_width) {
                        cairo_restore (cr);
+                       needs_restore = FALSE;
+               }
                if (go_styled_object_set_cairo_line (GO_STYLED_OBJECT (item), cr))
                        cairo_stroke (cr);
                else
                        cairo_new_path (cr);
        }
-       if (scale_line_width)
+       if (needs_restore)
                cairo_restore (cr);
 }
 
diff --git a/goffice/canvas/goc-polyline.c b/goffice/canvas/goc-polyline.c
index a98acb8..c71df09 100644
--- a/goffice/canvas/goc-polyline.c
+++ b/goffice/canvas/goc-polyline.c
@@ -111,8 +111,11 @@ goc_polyline_prepare_draw (GocItem const *item, cairo_t *cr, gboolean flag)
        GocPolyline *polyline = GOC_POLYLINE (item);
        unsigned i;
        gboolean scale_line_width = goc_styled_item_get_scale_line_width (GOC_STYLED_ITEM (item));
+       gboolean needs_restore;
 
        cairo_save (cr);
+       needs_restore = TRUE;
+
        _goc_item_transform (item, cr, flag);
        if (polyline->nb_points == 0)
                return FALSE;
@@ -148,15 +151,17 @@ goc_polyline_prepare_draw (GocItem const *item, cairo_t *cr, gboolean flag)
                }
        }
 
-       if (!scale_line_width)
+       if (!scale_line_width) {
                cairo_restore (cr);
+               needs_restore = FALSE;
+       }
        if (goc_styled_item_set_cairo_line (GOC_STYLED_ITEM (item), cr)) {
-               if (!scale_line_width)
+               if (needs_restore)
                        cairo_restore (cr);
                return TRUE;
        }
 
-       if (!scale_line_width)
+       if (needs_restore)
                cairo_restore (cr);
        return FALSE;
 }
@@ -222,7 +227,6 @@ goc_polyline_draw (GocItem const *item, cairo_t *cr)
        if (goc_polyline_prepare_draw (item, cr, 1)) {
                cairo_stroke (cr);
        }
-       cairo_restore (cr);
 }
 
 static void