core plugin: use const arrays for some strings

This makes very little difference to the compiler, as it can see all uses of
these strings. But this makes it clearer to readers that these variables are not
modified. Using an array instead of a pointer slightly increases flexibility,
allowing a useful application of `sizeof` to these variables should we ever want
to do that.

diff --git a/plugin/core/gvrender_core_svg.c b/plugin/core/gvrender_core_svg.c
index 4b2a6340181157b0e050d7cb30293f21b9ad7082..f86da09eb11998c7006658a1e7f555377e0220d2 100644 (file)
--- a/plugin/core/gvrender_core_svg.c
+++ b/plugin/core/gvrender_core_svg.c
@@ -46,13 +46,13 @@
 typedef enum { FORMAT_SVG, FORMAT_SVGZ, } format_type;
 
 /* SVG dash array */
-static char *sdasharray = "5,2";
+static const char sdasharray[] = "5,2";
 /* SVG dot array */
-static char *sdotarray = "1,5";
+static const char sdotarray[] = "1,5";
 
-static char *transparent = "transparent";
-static char *none = "none";
-static char *black = "black";
+static const char transparent[] = "transparent";
+static const char none[] = "none";
+static const char black[] = "black";
 
 static void svg_bzptarray(GVJ_t * job, pointf * A, int n)
 {