explorer segfault

[pat1]

python3 check.py 
None
arpae-aq
4390720
1240120
Errore di segmentazione (core dump creato)

check.zip

#!/usr/bin/python3
import dballe

with dballe.Explorer("report_fixed.json") as explorer:

    for cur in explorer.query_summary({'var': 'B12101'}):
        print (cur["ident"])
        print (cur["report"])
        print (cur.enqi("lat"))
        print (cur.enqi("lon"))
        print (cur["datetimemin"])
        print (cur["datetimemax"])
        print (cur["leveltype1"])
        print (cur["l1"])
        print (cur["leveltype2"])
        print (cur["l2"])
        print (cur["pindicator"])
        print (cur["p1"])
        print( cur["p2"])
        print( cur["var"])

[edigiacomo]

I cannot reproduce the problem with a JSON summary created from a BUFR message. Could you please provide the original BUFR corresponding to report_fixed.json?

[edigiacomo]

Ok, I think I have understood the problem. Debugging the program, I found that in https://github.com/ARPA-SIMC/dballe/blob/v8.12-1/dballe/db/summary-access.in.cc#L21 it seems that the items vector of station_entry is empty

      {<dballe::core::SmallSet<dballe::db::summary::VarEntry, dballe::db::summary::VarDesc, dballe::db::summary::station_entry_get_value>> = {items = std::vector of length 0, capacity 0, dirty = 0}, station = {report = "arpae-aq", coords = {lat = 4390720, lon = 1240120}, ident = {value = 0x0}}}

Then var_entry is equals to station_entry.end() and when the requested key is associated to var_entry, e.g. "datetimemax":

case "datetimemax": if (var_entry->dtrange.is_missing()) return; else enq.set_datetime(var_entry->dtrange.max.year);

And this causes the segmentation fault.

If I use an empty query, the problem doesn't occur because station_entry.items is always not empty.

[edigiacomo]

I have created PR #238, but I'm waiting for a review by @spanezz