xdot parsePolyline: standardize on returning 'NULL' instead of '0'

diff --git a/lib/xdot/xdot.c b/lib/xdot/xdot.c
index 7eb7228a3f05e80c26715044010ffd753396c363..fb8b019ac9ab634ad1ab20f0039f25def6028ce1 100644 (file)
--- a/lib/xdot/xdot.c
+++ b/lib/xdot/xdot.c
@@ -92,7 +92,7 @@ static char *parsePolyline(char *s, xdot_polyline * pp)
     char* endp;
 
     s = parseInt(s, &i);
-    if (!s) return s;
+    if (!s) return NULL;
     if (i < 0) return NULL;
     pts = ps = gv_calloc((size_t)i, sizeof(ps[0]));
     pp->cnt = i;
@@ -100,14 +100,14 @@ static char *parsePolyline(char *s, xdot_polyline * pp)
        ps->x = strtod (s, &endp);
        if (s == endp) {
            free (pts);
-           return 0;
+           return NULL;
        }
        else
            s = endp;
        ps->y = strtod (s, &endp);
        if (s == endp) {
            free (pts);
-           return 0;
+           return NULL;
        }
        else
            s = endp;