[librsvg/rustification] rsvg-path: Make RsvgPathBuilder a heap object

[Federico Mena Quintero <federico src gnome org>]

commit 32f2115e7a4a70a2f72cce87323605cdebae5bf2
Author: Federico Mena Quintero <federico gnome org>
Date:   Mon Oct 31 13:45:22 2016 -0600

    rsvg-path: Make RsvgPathBuilder a heap object
    
    We introduce rsvg_path_builder_new() and rsvg_path_builder_destroy(),
    and change rsvg_path_builder_finish() into an
    rsvg_path_builder_copy_path() that does not destroy the builder while
    extracting the path.
    
    This will make it easier to have long-lived path builders, so that
    callers can render to Cairo directoy from them instead of extracting the
    path themselves.

 rsvg-path.c   |   79 ++++++++++++++++++++++++++++-------------
 rsvg-path.h   |    7 +++-
 rsvg-shapes.c |  110 ++++++++++++++++++++++++++++++--------------------------
 3 files changed, 118 insertions(+), 78 deletions(-)
---
diff --git a/rsvg-path.c b/rsvg-path.c
index 3a5295a..27dbb7b 100644
--- a/rsvg-path.c
+++ b/rsvg-path.c
@@ -47,7 +47,7 @@
 typedef struct _RSVGParsePathCtx RSVGParsePathCtx;
 
 struct _RSVGParsePathCtx {
-    RsvgPathBuilder builder;
+    RsvgPathBuilder *builder;
 
     cairo_path_data_t cp;       /* current point */
     cairo_path_data_t rp;       /* reflection point (for 's' and 't' commands) */
@@ -70,14 +70,31 @@ rsvg_path_builder_add_element (RsvgPathBuilder *builder,
   g_array_append_val (builder->path_data, *data);
 }
 
+RsvgPathBuilder *
+rsvg_path_builder_new (void)
+{
+    RsvgPathBuilder *builder;
+
+    builder = g_new (RsvgPathBuilder, 1);
+
+    /* The starting capacity is just to avoid lots of little resizes while growing
+     * a small path.  After that, it will grow as needed.
+     */
+    builder->path_data = g_array_sized_new (FALSE, FALSE, sizeof (cairo_path_data_t), 32);
+    builder->last_move_to_index = -1;
+
+    return builder;
+}
+
 void
-rsvg_path_builder_init (RsvgPathBuilder *builder)
+rsvg_path_builder_destroy (RsvgPathBuilder *builder)
 {
-  /* The starting capacity is just to avoid lots of little resizes while growing
-   * a small path.  After that, it will grow as needed.
-   */
-  builder->path_data = g_array_sized_new (FALSE, FALSE, sizeof (cairo_path_data_t), 32);
-  builder->last_move_to_index = -1;
+    g_assert (builder != NULL);
+
+    g_array_free (builder->path_data, TRUE);
+    builder->path_data = NULL;
+    builder->last_move_to_index = -1;
+    g_free (builder);
 }
 
 void
@@ -163,15 +180,22 @@ rsvg_path_builder_close_path (RsvgPathBuilder *builder)
 }
 
 cairo_path_t *
-rsvg_path_builder_finish (RsvgPathBuilder *builder)
+rsvg_path_builder_copy_path (RsvgPathBuilder *builder)
 {
     cairo_path_t *path;
+    int i;
 
     path = g_new (cairo_path_t, 1);
     path->status = CAIRO_STATUS_SUCCESS;
-    path->data = (cairo_path_data_t *) builder->path_data->data; /* adopt array segment */
     path->num_data = builder->path_data->len;
-    g_array_free (builder->path_data, FALSE);
+    path->data = g_new (cairo_path_data_t, path->num_data);
+
+    for (i = 0; i < path->num_data; i++) {
+        cairo_path_data_t *data;
+
+        data = &g_array_index (builder->path_data, cairo_path_data_t, i);
+        path->data[i] = *data;
+    }
 
     return path;
 }
@@ -371,7 +395,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
         /* moveto */
         if (ctx->param == 2 || final) {
             rsvg_parse_path_default_xy (ctx, 2);
-            rsvg_path_builder_move_to (&ctx->builder, ctx->params[0], ctx->params[1]);
+            rsvg_path_builder_move_to (ctx->builder, ctx->params[0], ctx->params[1]);
             ctx->cp.point.x = ctx->rp.point.x = ctx->params[0];
             ctx->cp.point.y = ctx->rp.point.y = ctx->params[1];
             ctx->param = 0;
@@ -382,7 +406,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
         /* lineto */
         if (ctx->param == 2 || final) {
             rsvg_parse_path_default_xy (ctx, 2);
-            rsvg_path_builder_line_to (&ctx->builder, ctx->params[0], ctx->params[1]);
+            rsvg_path_builder_line_to (ctx->builder, ctx->params[0], ctx->params[1]);
             ctx->cp.point.x = ctx->rp.point.x = ctx->params[0];
             ctx->cp.point.y = ctx->rp.point.y = ctx->params[1];
             ctx->param = 0;
@@ -398,7 +422,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
             y2 = ctx->params[3];
             x3 = ctx->params[4];
             y3 = ctx->params[5];
-            rsvg_path_builder_curve_to (&ctx->builder, x1, y1, x2, y2, x3, y3);
+            rsvg_path_builder_curve_to (ctx->builder, x1, y1, x2, y2, x3, y3);
             ctx->rp.point.x = x2;
             ctx->rp.point.y = y2;
             ctx->cp.point.x = x3;
@@ -416,7 +440,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
             y2 = ctx->params[1];
             x3 = ctx->params[2];
             y3 = ctx->params[3];
-            rsvg_path_builder_curve_to (&ctx->builder, x1, y1, x2, y2, x3, y3);
+            rsvg_path_builder_curve_to (ctx->builder, x1, y1, x2, y2, x3, y3);
             ctx->rp.point.x = x2;
             ctx->rp.point.y = y2;
             ctx->cp.point.x = x3;
@@ -427,7 +451,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
     case 'h':
         /* horizontal lineto */
         if (ctx->param == 1) {
-            rsvg_path_builder_line_to (&ctx->builder, ctx->params[0], ctx->cp.point.y);
+            rsvg_path_builder_line_to (ctx->builder, ctx->params[0], ctx->cp.point.y);
             ctx->cp.point.x = ctx->rp.point.x = ctx->params[0];
             ctx->rp.point.y = ctx->cp.point.y;
             ctx->param = 0;
@@ -436,7 +460,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
     case 'v':
         /* vertical lineto */
         if (ctx->param == 1) {
-            rsvg_path_builder_line_to (&ctx->builder, ctx->cp.point.x, ctx->params[0]);
+            rsvg_path_builder_line_to (ctx->builder, ctx->cp.point.x, ctx->params[0]);
             ctx->rp.point.x = ctx->cp.point.x;
             ctx->cp.point.y = ctx->rp.point.y = ctx->params[0];
             ctx->param = 0;
@@ -457,7 +481,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
             y3 = ctx->params[3];
             x2 = (x3 + 2 * ctx->params[0]) * (1.0 / 3.0);
             y2 = (y3 + 2 * ctx->params[1]) * (1.0 / 3.0);
-            rsvg_path_builder_curve_to (&ctx->builder, x1, y1, x2, y2, x3, y3);
+            rsvg_path_builder_curve_to (ctx->builder, x1, y1, x2, y2, x3, y3);
             ctx->rp.point.x = ctx->params[0];
             ctx->rp.point.y = ctx->params[1];
             ctx->cp.point.x = x3;
@@ -479,7 +503,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
             y3 = ctx->params[1];
             x2 = (x3 + 2 * xc) * (1.0 / 3.0);
             y2 = (y3 + 2 * yc) * (1.0 / 3.0);
-            rsvg_path_builder_curve_to (&ctx->builder, x1, y1, x2, y2, x3, y3);
+            rsvg_path_builder_curve_to (ctx->builder, x1, y1, x2, y2, x3, y3);
             ctx->rp.point.x = xc;
             ctx->rp.point.y = yc;
             ctx->cp.point.x = x3;
@@ -495,14 +519,14 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
                 y3 = ctx->params[3];
                 x2 = (x3 + 2 * ctx->params[0]) * (1.0 / 3.0);
                 y2 = (y3 + 2 * ctx->params[1]) * (1.0 / 3.0);
-                rsvg_path_builder_curve_to (&ctx->builder, x1, y1, x2, y2, x3, y3);
+                rsvg_path_builder_curve_to (ctx->builder, x1, y1, x2, y2, x3, y3);
                 ctx->rp.point.x = ctx->params[0];
                 ctx->rp.point.y = ctx->params[1];
                 ctx->cp.point.x = x3;
                 ctx->cp.point.y = y3;
             } else {
                 rsvg_parse_path_default_xy (ctx, 2);
-                rsvg_path_builder_line_to (&ctx->builder, ctx->params[0], ctx->params[1]);
+                rsvg_path_builder_line_to (ctx->builder, ctx->params[0], ctx->params[1]);
                 ctx->cp.point.x = ctx->rp.point.x = ctx->params[0];
                 ctx->cp.point.y = ctx->rp.point.y = ctx->params[1];
             }
@@ -532,7 +556,7 @@ rsvg_parse_path_do_cmd (RSVGParsePathCtx * ctx, gboolean final)
             x2 = ctx->params[5];
             y2 = ctx->params[6];
 
-            rsvg_path_builder_arc (&ctx->builder,
+            rsvg_path_builder_arc (ctx->builder,
                                    x1, y1,
                                    rx, ry,
                                    x_axis_rotation,
@@ -715,9 +739,9 @@ rsvg_parse_path_data (RSVGParsePathCtx * ctx, const char *data)
         } else if (c == 'z' || c == 'Z') {
             if (ctx->param)
                 rsvg_parse_path_do_cmd (ctx, TRUE);
-            rsvg_path_builder_close_path (&ctx->builder);
+            rsvg_path_builder_close_path (ctx->builder);
 
-            ctx->cp = ctx->rp = g_array_index (ctx->builder.path_data, cairo_path_data_t, 
ctx->builder.path_data->len - 1);
+            ctx->cp = ctx->rp = g_array_index (ctx->builder->path_data, cairo_path_data_t, 
ctx->builder->path_data->len - 1);
         } else if (c >= 'A' && c < 'Z' && c != 'E') {
             if (ctx->param)
                 rsvg_parse_path_do_cmd (ctx, TRUE);
@@ -737,8 +761,9 @@ cairo_path_t *
 rsvg_parse_path (const char *path_str)
 {
     RSVGParsePathCtx ctx;
+    cairo_path_t *path;
 
-    rsvg_path_builder_init (&ctx.builder);
+    ctx.builder = rsvg_path_builder_new ();
 
     ctx.cp.point.x = 0.0;
     ctx.cp.point.y = 0.0;
@@ -752,7 +777,11 @@ rsvg_parse_path (const char *path_str)
     if (ctx.param)
         rsvg_parse_path_do_cmd (&ctx, TRUE);
 
-    return rsvg_path_builder_finish (&ctx.builder);
+    path = rsvg_path_builder_copy_path (ctx.builder);
+
+    rsvg_path_builder_destroy (ctx.builder);
+
+    return path;
 }
 
 void
diff --git a/rsvg-path.h b/rsvg-path.h
index 25e67fa..68269e0 100644
--- a/rsvg-path.h
+++ b/rsvg-path.h
@@ -40,7 +40,10 @@ typedef struct {
 } RsvgPathBuilder;
 
 G_GNUC_INTERNAL
-void rsvg_path_builder_init (RsvgPathBuilder *builder);
+RsvgPathBuilder *rsvg_path_builder_new (void);
+
+G_GNUC_INTERNAL
+void rsvg_path_builder_destroy (RsvgPathBuilder *builder);
 
 G_GNUC_INTERNAL
 void rsvg_path_builder_move_to (RsvgPathBuilder *builder,
@@ -70,7 +73,7 @@ void rsvg_path_builder_arc (RsvgPathBuilder *builder,
 G_GNUC_INTERNAL
 void rsvg_path_builder_close_path (RsvgPathBuilder *builder);
 G_GNUC_INTERNAL
-cairo_path_t *rsvg_path_builder_finish (RsvgPathBuilder *builder);
+cairo_path_t *rsvg_path_builder_copy_path (RsvgPathBuilder *builder);
 G_GNUC_INTERNAL
 cairo_path_t *rsvg_parse_path (const char *path_str);
 G_GNUC_INTERNAL
diff --git a/rsvg-shapes.c b/rsvg-shapes.c
index b883474..102d40c 100644
--- a/rsvg-shapes.c
+++ b/rsvg-shapes.c
@@ -153,7 +153,7 @@ _rsvg_node_poly_build_path (const char *value,
 {
     double *pointlist;
     guint pointlist_len, i;
-    RsvgPathBuilder builder;
+    RsvgPathBuilder *builder;
     cairo_path_t *path;
 
     pointlist = rsvg_css_parse_number_list (value, &pointlist_len);
@@ -165,9 +165,9 @@ _rsvg_node_poly_build_path (const char *value,
         return NULL;
     }
 
-    rsvg_path_builder_init (&builder);
+    builder = rsvg_path_builder_new ();
 
-    rsvg_path_builder_move_to (&builder, pointlist[0], pointlist[1]);
+    rsvg_path_builder_move_to (builder, pointlist[0], pointlist[1]);
 
     for (i = 2; i < pointlist_len; i += 2) {
         double x, y;
@@ -183,15 +183,17 @@ _rsvg_node_poly_build_path (const char *value,
         else
             y = pointlist[i - 1];
 
-        rsvg_path_builder_line_to (&builder, x, y);
+        rsvg_path_builder_line_to (builder, x, y);
     }
 
     if (close_path)
-        rsvg_path_builder_close_path (&builder);
+        rsvg_path_builder_close_path (builder);
 
-    path = rsvg_path_builder_finish (&builder);
+    path = rsvg_path_builder_copy_path (builder);
     g_free (pointlist);
 
+    rsvg_path_builder_destroy (builder);
+
     return path;
 }
 
@@ -281,21 +283,23 @@ static void
 _rsvg_node_line_draw (RsvgNode * overself, RsvgDrawingCtx * ctx, int dominate)
 {
     cairo_path_t *path;
-    RsvgPathBuilder builder;
+    RsvgPathBuilder *builder;
     RsvgNodeLine *self = (RsvgNodeLine *) overself;
     double x1, y1, x2, y2;
 
-    rsvg_path_builder_init (&builder);
+    builder = rsvg_path_builder_new ();
 
     x1 = _rsvg_css_normalize_length (&self->x1, ctx, 'h');
     y1 = _rsvg_css_normalize_length (&self->y1, ctx, 'v');
     x2 = _rsvg_css_normalize_length (&self->x2, ctx, 'h');
     y2 = _rsvg_css_normalize_length (&self->y2, ctx, 'v');
 
-    rsvg_path_builder_move_to (&builder, x1, y1);
-    rsvg_path_builder_line_to (&builder, x2, y2);
+    rsvg_path_builder_move_to (builder, x1, y1);
+    rsvg_path_builder_line_to (builder, x2, y2);
+
+    path = rsvg_path_builder_copy_path (builder);
 
-    path = rsvg_path_builder_finish (&builder);
+    rsvg_path_builder_destroy (builder);
 
     rsvg_state_reinherit_top (ctx, overself->state, dominate);
 
@@ -363,7 +367,7 @@ _rsvg_node_rect_draw (RsvgNode * self, RsvgDrawingCtx * ctx, int dominate)
 {
     double x, y, w, h, rx, ry;
     double half_w, half_h;
-    RsvgPathBuilder builder;
+    RsvgPathBuilder *builder;
     cairo_path_t *path;
     RsvgNodeRect *rect = (RsvgNodeRect *) self;
 
@@ -405,17 +409,17 @@ _rsvg_node_rect_draw (RsvgNode * self, RsvgDrawingCtx * ctx, int dominate)
     else if (ry == 0)
         rx = 0;
 
+    builder = rsvg_path_builder_new ();
+
     if (rx == 0) {
         /* Easy case, no rounded corners */
 
-        rsvg_path_builder_init (&builder);
-
-        rsvg_path_builder_move_to (&builder, x, y);
-        rsvg_path_builder_line_to (&builder, x + w, y);
-        rsvg_path_builder_line_to (&builder, x + w, y + h);
-        rsvg_path_builder_line_to (&builder, x, y + h);
-        rsvg_path_builder_line_to (&builder, x, y);
-        rsvg_path_builder_close_path (&builder);
+        rsvg_path_builder_move_to (builder, x, y);
+        rsvg_path_builder_line_to (builder, x + w, y);
+        rsvg_path_builder_line_to (builder, x + w, y + h);
+        rsvg_path_builder_line_to (builder, x, y + h);
+        rsvg_path_builder_line_to (builder, x, y);
+        rsvg_path_builder_close_path (builder);
     } else {
         double top_x1, top_x2, top_y;
         double bottom_x1, bottom_x2, bottom_y;
@@ -459,41 +463,41 @@ _rsvg_node_rect_draw (RsvgNode * self, RsvgDrawingCtx * ctx, int dominate)
         right_y1 = left_y1;
         right_y2 = left_y2;
 
-        rsvg_path_builder_init (&builder);
+        rsvg_path_builder_move_to (builder, top_x1, top_y);
+        rsvg_path_builder_line_to (builder, top_x2, top_y);
 
-        rsvg_path_builder_move_to (&builder, top_x1, top_y);
-        rsvg_path_builder_line_to (&builder, top_x2, top_y);
-
-        rsvg_path_builder_arc (&builder,
+        rsvg_path_builder_arc (builder,
                                top_x2, top_y,
                                rx, ry, 0, FALSE, TRUE,
                                right_x, right_y1);
 
-        rsvg_path_builder_line_to (&builder, right_x, right_y2);
+        rsvg_path_builder_line_to (builder, right_x, right_y2);
 
-        rsvg_path_builder_arc (&builder,
+        rsvg_path_builder_arc (builder,
                                right_x, right_y2,
                                rx, ry, 0, FALSE, TRUE,
                                bottom_x2, bottom_y);
 
-        rsvg_path_builder_line_to (&builder, bottom_x1, bottom_y);
+        rsvg_path_builder_line_to (builder, bottom_x1, bottom_y);
 
-        rsvg_path_builder_arc (&builder,
+        rsvg_path_builder_arc (builder,
                                bottom_x1, bottom_y,
                                rx, ry, 0, FALSE, TRUE,
                                left_x, left_y2);
 
-        rsvg_path_builder_line_to (&builder, left_x, left_y1);
+        rsvg_path_builder_line_to (builder, left_x, left_y1);
 
-        rsvg_path_builder_arc (&builder,
+        rsvg_path_builder_arc (builder,
                                left_x, left_y1,
                                rx, ry, 0, FALSE, TRUE,
                                top_x1, top_y);
 
-        rsvg_path_builder_close_path (&builder);
+        rsvg_path_builder_close_path (builder);
     }
 
-    path = rsvg_path_builder_finish (&builder);
+    path = rsvg_path_builder_copy_path (builder);
+
+    rsvg_path_builder_destroy (builder);
 
     rsvg_state_reinherit_top (ctx, self->state, dominate);
     rsvg_render_path (ctx, path);
@@ -550,7 +554,7 @@ _rsvg_node_circle_draw (RsvgNode * self, RsvgDrawingCtx * ctx, int dominate)
     cairo_path_t *path;
     RsvgNodeCircle *circle = (RsvgNodeCircle *) self;
     double cx, cy, r;
-    RsvgPathBuilder builder;
+    RsvgPathBuilder *builder;
 
     cx = _rsvg_css_normalize_length (&circle->cx, ctx, 'h');
     cy = _rsvg_css_normalize_length (&circle->cy, ctx, 'v');
@@ -561,33 +565,35 @@ _rsvg_node_circle_draw (RsvgNode * self, RsvgDrawingCtx * ctx, int dominate)
 
     /* approximate a circle using 4 bezier curves */
 
-    rsvg_path_builder_init (&builder);
+    builder = rsvg_path_builder_new ();
 
-    rsvg_path_builder_move_to (&builder, cx + r, cy);
+    rsvg_path_builder_move_to (builder, cx + r, cy);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx + r, cy + r * RSVG_ARC_MAGIC,
                                 cx + r * RSVG_ARC_MAGIC, cy + r,
                                 cx, cy + r);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx - r * RSVG_ARC_MAGIC, cy + r,
                                 cx - r, cy + r * RSVG_ARC_MAGIC,
                                 cx - r, cy);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx - r, cy - r * RSVG_ARC_MAGIC,
                                 cx - r * RSVG_ARC_MAGIC, cy - r,
                                 cx, cy - r);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx + r * RSVG_ARC_MAGIC, cy - r,
                                 cx + r, cy - r * RSVG_ARC_MAGIC,
                                 cx + r, cy);
 
-    rsvg_path_builder_close_path (&builder);
+    rsvg_path_builder_close_path (builder);
 
-    path = rsvg_path_builder_finish (&builder);
+    path = rsvg_path_builder_copy_path (builder);
+
+    rsvg_path_builder_destroy (builder);
 
     rsvg_state_reinherit_top (ctx, self->state, dominate);
     rsvg_render_path (ctx, path);
@@ -645,7 +651,7 @@ _rsvg_node_ellipse_draw (RsvgNode * self, RsvgDrawingCtx * ctx, int dominate)
     RsvgNodeEllipse *ellipse = (RsvgNodeEllipse *) self;
     cairo_path_t *path;
     double cx, cy, rx, ry;
-    RsvgPathBuilder builder;
+    RsvgPathBuilder *builder;
 
     cx = _rsvg_css_normalize_length (&ellipse->cx, ctx, 'h');
     cy = _rsvg_css_normalize_length (&ellipse->cy, ctx, 'v');
@@ -657,33 +663,35 @@ _rsvg_node_ellipse_draw (RsvgNode * self, RsvgDrawingCtx * ctx, int dominate)
 
     /* approximate an ellipse using 4 bezier curves */
 
-    rsvg_path_builder_init (&builder);
+    builder = rsvg_path_builder_new ();
 
-    rsvg_path_builder_move_to (&builder, cx + rx, cy);
+    rsvg_path_builder_move_to (builder, cx + rx, cy);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx + rx, cy - RSVG_ARC_MAGIC * ry,
                                 cx + RSVG_ARC_MAGIC * rx, cy - ry,
                                 cx, cy - ry);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx - RSVG_ARC_MAGIC * rx, cy - ry,
                                 cx - rx, cy - RSVG_ARC_MAGIC * ry,
                                 cx - rx, cy);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx - rx, cy + RSVG_ARC_MAGIC * ry,
                                 cx - RSVG_ARC_MAGIC * rx, cy + ry,
                                 cx, cy + ry);
 
-    rsvg_path_builder_curve_to (&builder,
+    rsvg_path_builder_curve_to (builder,
                                 cx + RSVG_ARC_MAGIC * rx, cy + ry,
                                 cx + rx, cy + RSVG_ARC_MAGIC * ry,
                                 cx + rx, cy);
 
-    rsvg_path_builder_close_path (&builder);
+    rsvg_path_builder_close_path (builder);
+
+    path = rsvg_path_builder_copy_path (builder);
 
-    path = rsvg_path_builder_finish (&builder);
+    rsvg_path_builder_destroy (builder);
 
     rsvg_state_reinherit_top (ctx, self->state, dominate);
     rsvg_render_path (ctx, path);