make sure we do not try to draw points all that far outside the drawing area

[rrdtool.git] / src / rrd_graph.c

diff --git a/src/rrd_graph.c b/src/rrd_graph.c
index 898b6ff..d902a93 100644 (file)
--- a/src/rrd_graph.c
+++ b/src/rrd_graph.c
@@ -1582,7 +1582,7 @@ int print_calc(
                 }
             }           /* prepare printval */
 
-            if ((percent_s = strstr(im->gdes[i].format, "%S")) != NULL) {
+            if (!im->gdes[i].strftm && (percent_s = strstr(im->gdes[i].format, "%S")) != NULL) {
                 /* Magfact is set to -1 upon entry to print_calc.  If it
                  * is still less than 0, then we need to run auto_scale.
                  * Otherwise, put the value into the correct units.  If
@@ -1596,7 +1596,7 @@ int print_calc(
                     printval /= magfact;
                 }
                 *(++percent_s) = 's';
-            } else if (strstr(im->gdes[i].format, "%s") != NULL) {
+            } else if (!im->gdes[i].strftm && strstr(im->gdes[i].format, "%s") != NULL) {
                 auto_scale(im, &printval, &si_symb, &magfact);
             }
 
@@ -3448,17 +3448,27 @@ int graph_paint(
             break;
         case GF_LINE:
         case GF_AREA:
-               case GF_GRAD:
-            /* fix data points at oo and -oo */
+        case GF_GRAD: {
+            rrd_value_t diffval = im->maxval - im->minval;
+            rrd_value_t maxlimit = im->maxval + 9 * diffval;
+            rrd_value_t minlimit = im->minval - 9 * diffval;        
             for (ii = 0; ii < im->xsize; ii++) {
+                /* fix data points at oo and -oo */
                 if (isinf(im->gdes[i].p_data[ii])) {
                     if (im->gdes[i].p_data[ii] > 0) {
                         im->gdes[i].p_data[ii] = im->maxval;
                     } else {
                         im->gdes[i].p_data[ii] = im->minval;
                     }
-
                 }
+                /* some versions of cairo go unstable when trying
+                   to draw way out of the canvas ... lets not even try */
+               if (im->gdes[i].p_data[ii] > maxlimit) {
+                   im->gdes[i].p_data[ii] = maxlimit;
+               }
+               if (im->gdes[i].p_data[ii] < minlimit) {
+                   im->gdes[i].p_data[ii] = minlimit;
+               }
             }           /* for */
 
             /* *******************************************************
@@ -3726,6 +3736,7 @@ int graph_paint(
             }
             lastgdes = &(im->gdes[i]);
             break;
+        } /* GF_AREA, GF_LINE, GF_GRAD */
         case GF_STACK:
             rrd_set_error
                 ("STACK should already be turned into LINE or AREA here");