[cairo-polygon] Clean-up realloc algorithm for clarity

1 files changed, 7 insertions, 11 deletions

diff --git a/src/cairo-polygon.c b/src/cairo-polygon.c
index dc9d3805b..bdd438a63 100644
--- a/src/cairo-polygon.c
+++ b/src/cairo-polygon.c
@@ -40,7 +40,7 @@
 /* private functions */
 
 static cairo_status_t
-_cairo_polygon_grow_by (cairo_polygon_t *polygon, int additional);
+_cairo_polygon_grow (cairo_polygon_t *polygon);
 
 void
 _cairo_polygon_init (cairo_polygon_t *polygon)
@@ -67,25 +67,22 @@ _cairo_polygon_fini (cairo_polygon_t *polygon)
 }
 
 static cairo_status_t
-_cairo_polygon_grow_by (cairo_polygon_t *polygon, int additional)
+_cairo_polygon_grow (cairo_polygon_t *polygon)
 {
     cairo_edge_t *new_edges;
     int old_size = polygon->edges_size;
-    int new_size = polygon->num_edges + additional;
+    int new_size = old_size ? 2 * old_size : 16;
 
-    if (new_size <= polygon->edges_size) {
-	return CAIRO_STATUS_SUCCESS;
-    }
+    assert (polygon->num_edges <= polygon->edges_size);
 
-    polygon->edges_size = new_size;
-    new_edges = realloc (polygon->edges, polygon->edges_size * sizeof (cairo_edge_t));
+    new_edges = realloc (polygon->edges, new_size * sizeof (cairo_edge_t));
 
     if (new_edges == NULL) {
-	polygon->edges_size = old_size;
 	return CAIRO_STATUS_NO_MEMORY;
     }
 
     polygon->edges = new_edges;
+    polygon->edges_size = new_size;
 
     return CAIRO_STATUS_SUCCESS;
 }
@@ -102,8 +99,7 @@ _cairo_polygon_add_edge (cairo_polygon_t *polygon, cairo_point_t *p1, cairo_poin
     }
 
     if (polygon->num_edges >= polygon->edges_size) {
-	int additional = polygon->edges_size ? polygon->edges_size : 16;
-	status = _cairo_polygon_grow_by (polygon, additional);
+	status = _cairo_polygon_grow (polygon);
 	if (status) {
 	    return status;
 	}