sms.db: silence libdbi warnings on out-of-range index

Apparently, since libdbi 0.9.0 aka 0.9.0-5 on debian-testing, osmo-msc barfs
numerous libdbi warnings whenever a query rightfully returns no rows.

Trivially query whether there are any rows first by adding an inline wrap
function next_row().

Silenced:

  DDB <000d> ../../../../src/osmo-msc/src/libmsc/db.c:188 DBI: -6: An invalid or out-of-range index was passed to l
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:47 backtrace() returned 11 addresses
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/local/bin/osmo-msc(+0xfb81) [0x555555563b81]
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/lib/x86_64-linux-gnu/libdbi.so.1(_error_handle
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/lib/x86_64-linux-gnu/libdbi.so.1(dbi_result_ne
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/local/bin/osmo-msc(+0x11172) [0x555555565172]
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/local/bin/osmo-msc(+0x1e6bc) [0x5555555726bc]
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/local/bin/osmo-msc(+0x1e7f6) [0x5555555727f6]
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/local/bin/osmo-msc(+0x1f1d2) [0x5555555731d2]
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/local/bin/osmo-msc(+0xbb86) [0x55555555fb86]
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0
  DDB <000d> ../../../src/libosmocore/src/backtrace.c:57        /usr/local/bin/osmo-msc(+0xbfba) [0x55555555ffba]

Related: OS#2737 OS#2667
Change-Id: I43cf4eed22425554826d59857eded5b4cc0d2c52
1 file changed
tree: 86e43d6a45d7858c7ecaa3ef7ed27b39c5dbbc75
  1. contrib/
  2. debian/
  3. openbsc/
  4. .gitignore
  5. .gitreview
  6. .mailmap