When collecting data, spine should be stripping alpha characters from output

[TheWitness]

Describe the bug
In prior releases of spine, if a value was returned from snmp that not numeric, spine used to strip those characters automatically in an attempt to create valid output, but now it's not.

Expected behavior
Strip alpha characters off of the SNMP output as expected.

[eriksejr]

@TheWitness This patch actually has to go in two locations to make sure the alpha is stripped from the result:

--- poller.c.orig       2020-03-28 11:19:05.740000000 -0400
+++ poller.c    2020-03-30 09:32:59.180000000 -0400
@@ -1173,8 +1173,10 @@
                                                                /* is valid output, continue */
                                                        } else {
                                                                /* remove double or single quotes from string */
-                                                               snprintf(temp_result, RESULTS_BUFFER, "%s", snmp_oids[j].result);
+                                                               snprintf(temp_result, RESULTS_BUFFER, "%s", strip_alpha(trim(snmp_oids[j].result)));
                                                                snprintf(snmp_oids[j].result , RESULTS_BUFFER, "%s", %s",host_id, snmp_oids[j].result));

                                                                /* detect erroneous non-numeric result */
                                                                if (!validate_result(snmp_oids[j].result)) {
@@ -1474,8 +1476,10 @@
                                        /* is valid output, continue */
                                } else {
                                        /* remove double or single quotes from string */
-                                       snprintf(temp_result, RESULTS_BUFFER, "%s", snmp_oids[j].result);
+                                       snprintf(temp_result, RESULTS_BUFFER, "%s", strip_alpha(trim(snmp_oids[j].result)));
                                        snprintf(snmp_oids[j].result , RESULTS_BUFFER, "%s", temp_result);

                                        /* detect erroneous non-numeric result */
                                        if (!validate_result(snmp_oids[j].result)) {

But I'm still trying to test this further. After the patch I referenced in the forum post I was seeing spine terminate early sometimes creating some broken graphs:

The logs show segmentation faults on some runs, but I'm having problems consistently reproducing them, so I have not been able to track down the cause. Reverting the patch stops the segfaults.

[eriksejr]

I'm still running this as a test, so far It's working well, I have not reproduced the issues shown above, but I'd like to let it go for a day or two and I'll follow up and let you know if I see any problems with it

[eriksejr]

This has been running overnight with no further issues noted now. One thing I changed was to remove a number of bad data sources for which polling was failing anyway, that may have helped with regards to the broken graph.

[TheWitness]

Take another peak at what's in GitHub now. Thanks.