X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fcartesian.c;h=9dceb304ebb75c33477d5989b9bac0b512ba5baf;hb=4a73877b4d56caed03d383fb4d38347a9774046f;hp=cac18400a4e9e85c6b1dc78bc795b3323b76dd4c;hpb=5501903810bcbae487b12bc44d9cbedf29644d96;p=pspp-builds.git

diff --git a/src/cartesian.c b/src/cartesian.c
index cac18400..9dceb304 100644
--- a/src/cartesian.c
+++ b/src/cartesian.c
@@ -14,8 +14,8 @@
 
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
-   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
-   02111-1307, USA. */
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301, USA. */
 
 
 #include <math.h>
@@ -53,6 +53,8 @@ write_legend(struct chart *chart, const char *heading, int n);
 void 
 chart_write_xlabel(struct chart *ch, const char *label)
 {
+  if ( ! ch ) 
+    return ;
 
   pl_savestate_r(ch->lp);
 
@@ -69,6 +71,9 @@ chart_write_xlabel(struct chart *ch, const char *label)
 void 
 chart_write_ylabel(struct chart *ch, const char *label)
 {
+  if ( ! ch ) 
+    return ;
+
   pl_savestate_r(ch->lp);
 
   pl_move_r(ch->lp, ch->data_bottom, ch->ordinate_right);
@@ -86,6 +91,10 @@ write_legend(struct chart *chart, const char *heading,
 {
   int ds;
 
+  if ( ! chart ) 
+    return ;
+
+
   pl_savestate_r(chart->lp);
 
   pl_filltype_r(chart->lp,1);
@@ -124,19 +133,22 @@ write_legend(struct chart *chart, const char *heading,
 void
 chart_datum(struct chart *ch, int dataset UNUSED, double x, double y)
 {
-  const double x_pos = 
-    (x - ch->x_min) * ch->abscissa_scale + ch->data_left ; 
+  if ( ! ch ) 
+    return ;
 
-  const double y_pos = 
-    (y - ch->y_min) * ch->ordinate_scale + ch->data_bottom ;
+  {
+    const double x_pos = 
+      (x - ch->x_min) * ch->abscissa_scale + ch->data_left ; 
 
+    const double y_pos = 
+      (y - ch->y_min) * ch->ordinate_scale + ch->data_bottom ;
 
-  pl_savestate_r(ch->lp);    
+    pl_savestate_r(ch->lp);    
   
-  pl_fmarker_r(ch->lp, x_pos, y_pos, 6, 15);
-
-  pl_restorestate_r(ch->lp);    
+    pl_fmarker_r(ch->lp, x_pos, y_pos, 6, 15);
 
+    pl_restorestate_r(ch->lp);    
+  }
 }
 
 /* Draw a line with slope SLOPE and intercept INTERCEPT.
@@ -151,6 +163,10 @@ chart_line(struct chart *ch, double slope, double intercept,
   double x1, y1;
   double x2, y2 ;
 
+  if ( ! ch ) 
+    return ;
+
+
   if ( lim_dim == CHART_DIM_Y ) 
     {
       x1 = ( limit1 - intercept ) / slope ;