[Bug 506865] Re: snmp-net not working with lm-sensors

[undefined]

i believe that the patch for net-snmp debian bug #575810 should have
included:

-+                    (subfeature->mapping == 0) &&
++                    (subfeature->type == (feature->type << 8)) &&

i agree with the bug report that "subfeature->mapping == 0" causes snmpd
to only report the first feature, but the suggested/accepted patch
causes all subfeatures of all features to be reported, which is
definitely not the historical (ie debian lenny & ubuntu hardy) behavior
of snmpd.

now every subfeature (eg fan1_input, fan1_min, fan1_div & fan1_alarm) of
every feature (eg fan1) is reported, and to a casual observer they are
indistinguishable in the snmpd output because they are only identified
with the feature's name (eg "fan1"; ie "label = sensors_get_label(chip,
feature)").

what i believe was intended by the original code (ie
"subfeature->mapping == 0") was that only the first subfeature of each
feature would be reported (eg fan1_input), because that's the historical
output of snmpd and the primary output of the sensors command (eg the
other subfeatures are printed following fan1_input and within parens).

a quick "hack" to enable that functionality is "subfeature->type ==
(feature->type << 8)".  this is based off how sensors.h (lines 148-204)
spaces the subfeatures (line 148: "All the sensor types (in, fan, temp,
vid) are a multiple of 0x100 apart") and how that is based off the
associated feature (line 151: "SENSORS_SUBFEATURE_IN_INPUT =
SENSORS_FEATURE_IN << 8").

a more thorough patch would probably be logic similar to the sensors
command (ie for every feature [fan1] query what type it is
[SENSORS_FEATURE_FAN] and pull the appropriate subfeature by name
[SENSORS_SUBFEATURE_FAN_INPUT]), but that patch is much more invasive,
though it would also eliminate the imperfect guessing of feature type by
label (ie lmSensors.c, lines 973-996; eg "if (strstr(label, "V")) type =
VOLT_TYPE;").

the attached files show the "bad" snmpwalk output of the proposed (and
apparently accepted in maverick) patch and the "good" snmpwalk output of
my proposed patch (which is also attached as a patch to
60_libsensors_api.patch).

-- 
snmp-net not working with lm-sensors
https://bugs.launchpad.net/bugs/506865
You received this bug notification because you are a member of Ubuntu
Server Team, which is subscribed to net-snmp in ubuntu.