[librsvg] Factor out a function to add a node and its ancestors to the RsvgDrawingCtx's stack

[Federico Mena Quintero <federico src gnome org>]

commit 4e8de80c75930ddaf124804106efdc740b2b6615
Author: Federico Mena Quintero <federico gnome org>
Date:   Thu Mar 16 19:21:42 2017 -0600

    Factor out a function to add a node and its ancestors to the RsvgDrawingCtx's stack
    
    This bit of code was duplicated in three places; move it to a single
    function.

 rsvg-base.c         |   28 +++++++++++++++-------------
 rsvg-cairo-render.c |    9 +--------
 rsvg-private.h      |    4 +++-
 3 files changed, 19 insertions(+), 22 deletions(-)
---
diff --git a/rsvg-base.c b/rsvg-base.c
index ee655f1..cf3606d 100644
--- a/rsvg-base.c
+++ b/rsvg-base.c
@@ -1578,12 +1578,7 @@ rsvg_handle_get_dimensions_sub (RsvgHandle * handle, RsvgDimensionData * dimensi
         }
 
         g_assert (sself != NULL);
-        sself = rsvg_node_ref (sself);
-
-        while (sself != NULL) {
-            draw->drawsub_stack = g_slist_prepend (draw->drawsub_stack, sself);
-            sself = rsvg_node_get_parent (sself);
-        }
+        rsvg_drawing_ctx_add_node_and_ancestors_to_stack (draw, sself);
 
         rsvg_drawing_ctx_draw_node_from_stack (draw, handle->priv->treebase, 0);
         bbox = RSVG_CAIRO_RENDER (draw->render)->bbox;
@@ -1671,13 +1666,7 @@ rsvg_handle_get_position_sub (RsvgHandle * handle, RsvgPositionData * position_d
         goto bail;
 
     g_assert (node != NULL);
-
-    node = rsvg_node_ref (node);
-
-    while (node != NULL) {
-        draw->drawsub_stack = g_slist_prepend (draw->drawsub_stack, node);
-        node = rsvg_node_get_parent (node);
-    }
+    rsvg_drawing_ctx_add_node_and_ancestors_to_stack (draw, node);
 
     rsvg_drawing_ctx_draw_node_from_stack (draw, handle->priv->treebase, 0);
     bbox = RSVG_CAIRO_RENDER (draw->render)->bbox;
@@ -2314,6 +2303,19 @@ rsvg_drawing_ctx_release_node (RsvgDrawingCtx * ctx, RsvgNode *node)
 }
 
 void
+rsvg_drawing_ctx_add_node_and_ancestors_to_stack (RsvgDrawingCtx *draw_ctx, RsvgNode *node)
+{
+    if (node) {
+        node = rsvg_node_ref (node);
+
+        while (node != NULL) {
+            draw_ctx->drawsub_stack = g_slist_prepend (draw_ctx->drawsub_stack, node);
+            node = rsvg_node_get_parent (node);
+        }
+    }
+}
+
+void
 rsvg_drawing_ctx_draw_node_from_stack (RsvgDrawingCtx *ctx, RsvgNode *node, int dominate)
 {
     RsvgState *state;
diff --git a/rsvg-cairo-render.c b/rsvg-cairo-render.c
index 262a213..48c3507 100644
--- a/rsvg-cairo-render.c
+++ b/rsvg-cairo-render.c
@@ -232,14 +232,7 @@ rsvg_handle_render_cairo_sub (RsvgHandle * handle, cairo_t * cr, const char *id)
     if (!draw)
         return FALSE;
 
-    if (drawsub) {
-        drawsub = rsvg_node_ref (drawsub);
-
-        while (drawsub != NULL) {
-            draw->drawsub_stack = g_slist_prepend (draw->drawsub_stack, drawsub);
-            drawsub = rsvg_node_get_parent (drawsub);
-        }
-    }
+    rsvg_drawing_ctx_add_node_and_ancestors_to_stack (draw, drawsub);
 
     cairo_save (cr);
 
diff --git a/rsvg-private.h b/rsvg-private.h
index b735d72..6bb5c6c 100644
--- a/rsvg-private.h
+++ b/rsvg-private.h
@@ -453,7 +453,9 @@ G_GNUC_INTERNAL
 void rsvg_drawing_ctx_release_node              (RsvgDrawingCtx * ctx, RsvgNode *node);
 
 G_GNUC_INTERNAL
-void rsvg_drawing_ctx_draw_node_from_stack (RsvgDrawingCtx *ctx, RsvgNode *node, int dominate);
+void rsvg_drawing_ctx_add_node_and_ancestors_to_stack (RsvgDrawingCtx *draw_ctx, RsvgNode *node);
+G_GNUC_INTERNAL
+void rsvg_drawing_ctx_draw_node_from_stack            (RsvgDrawingCtx *ctx, RsvgNode *node, int dominate);
 
 G_GNUC_INTERNAL
 void rsvg_render_path_builder   (RsvgDrawingCtx * ctx, RsvgPathBuilder *builder);