a nan-safe add operator (ADDNAN) into rrd. I used it to add several incomplete graphs.

[rrdtool.git] / src / rrd_rpncalc.c

diff --git a/src/rrd_rpncalc.c b/src/rrd_rpncalc.c
index ed08662..839643b 100644 (file)
--- a/src/rrd_rpncalc.c
+++ b/src/rrd_rpncalc.c
@@ -178,6 +178,7 @@ void rpn_compact2str(
             add_op(OP_DEG2RAD, DEG2RAD)
             add_op(OP_AVG, AVG)
             add_op(OP_ABS, ABS)
+            add_op(OP_ADDNAN, ADDNAN)
 #undef add_op
     }
     (*str)[offset] = '\0';
@@ -374,6 +375,7 @@ rpnp_t   *rpn_parse(
             match_op(OP_DEG2RAD, DEG2RAD)
             match_op(OP_AVG, AVG)
             match_op(OP_ABS, ABS)
+            match_op(OP_ADDNAN, ADDNAN)
 #undef match_op
             else if ((sscanf(expr, DEF_NAM_FMT "%n", vname, &pos) == 1)
                      && ((rpnp[steps].ptr = (*lookup) (key_hash, vname)) !=
@@ -543,6 +545,19 @@ short rpn_calc(
                 + rpnstack->s[stptr];
             stptr--;
             break;
+        case OP_ADDNAN:
+            stackunderflow(1);
+                       if (isnan(rpnstack->s[stptr - 1])) {
+                   rpnstack->s[stptr - 1] = rpnstack->s[stptr];
+                       } else if (isnan(rpnstack->s[stptr])) {
+                   //rpnstack->s[stptr - 1] = rpnstack->s[stptr - 1];
+                       } else {
+                  rpnstack->s[stptr - 1] = rpnstack->s[stptr - 1]
+                   + rpnstack->s[stptr];
+                       }
+
+            stptr--;
+            break;
         case OP_SUB:
             stackunderflow(1);
             rpnstack->s[stptr - 1] = rpnstack->s[stptr - 1]