[dsc] DSC Release 2.4.0

[Jerry Lundström]

Hi all,

Since there have been a few major issues with the threaded capturing
code it is now default disabled and have to be enabled with a configure
option to use: `./configure --enable-threads ...`

A lot of work has been done to ensure stability and correct capturing,
as of now `dsc` is continuously running on the testing platforms with
simulated traffic and tests are performance every 5-15 minutes:

  https://dev.dns-oarc.net/jenkins/view/dsctest/

With the rewrite of the config parser to C it was missed that Hapy
allowed CR/LF within the values of the options.  Changing the C parser
to allow it is a bit of work and having CR/LF within the value may lead
to other issues so it is now documented that CR/LF are not allowed in
config option values.

  https://www.dns-oarc.net/files/dsc/dsc-2.4.0.tar.gz
  dacbe67ed724be2d6b96f3f1f2a4eb5509ee7f6541b3adf7188afeb708a6179f

Packages are available at:

  https://dev.dns-oarc.net/packages/

Fixes:
- The `-T` flag was just controlling pcap-thread usage of threads,
  it now controls all usage of threads including how signals are caught.
- Fix program name, was incorrectly set so it would be reported
  as `/dsc`.
- Use thread safe functions (_r).
- Handle very long config lines by not having a static buffer, instead
  let `getline()` allocate as needed.
- Use new activation in pcap-thread to activate the capturing of pcaps
  after the initial interval sync have been done during start-up.
- Use factions of second for start-up interval sync and interval wait.
- Fix memory leaks if config options was specified more then once.
- Use new absolute timed run in pcap-thread to more exactly end
  capturing at the interval.
- Fix config parsing, was checking for tab when should look for
  line feed.
- Exit correctly during pcap-thread run to honor `dump_reports_on_exit`.
- Use 100ms as default pcap-thread timeout, was 1s before but the
  old code used 250ms.
- Various enhancements to logging of errors.

New config options/features:
- `pcap_buffer_size` can be used to increase the capture buffer within
  pcap-thread/libpcap, this can help mitigate dropped packets by the
  kernel during interval breaks.
- `no_wait_interval` will skip the interval sync that happens during
  start-up and start capturing directly, the end of the interval will
  still be the modulus of the interval.
- `pcap_thread_timeout` can be used to change the internal timeout use
  in pcap-thread to wait for packets (default 100ms).
- Log non-fatal errors from pcap-thread w.r.t. setting the filter which
  can indicate that the filter is running in userland because lack of
  support or that it is too large for the kernel.

Special thanks to:
- Anand Buddhdev, RIPE NCC
- Klaus Darilion, NIC.AT
- Vincent Charrade, Nameshield

Commits:

ee59572 Fix #111, fix #116: Update pcap-thread to v2.0.0, remove debug
        code
64befef Update copyright year
40a1fb4 Fix #139: Use 100ms as default pcap-thread timeout
2a07185 Fix #137: Graceful exit on signal during run
f1b3ec3 Issue #116: Try and make select issue more clear
950ea96 Fix #133: Return from `Pcap_run()` on signal/errors
667cc91 Issue #116: Add config option pcap_thread_timeout
3c9e073 Notice if non-fatal errors was detected during activation
4ea8f54 Fix #108: Document that CR/LF are not allowed within configuration
        line
9fda332 Check for LF and not tab
15a1dc0 Use pcap-thread timed run to interface
1e98f8b Fix potential memory leaks if config options specified more then
        once
a9b38e9 Add missing LF and indicate what config option was wrong if
        possible
f8a2821 Use fractions of seconds for both start up interval sync and
        timed run, always adjust for inter-run processing delay
f47069a Fix #121: Update to pcap-thread latest develop
fc13d73 Issue #116: Feature for not waiting on the interval sync
c832337 Fix #122: Update pcap-thread to v1.2.3 for fix in timed run
4739111 Add `pcap_buffer_size` config option
7d9bf90 Update pcap-thread to v1.2.2
ef43335 Make threads optional and default disabled
c2399cf getline() returns error on eof, don't report error if we are
5c671e6 Clarify config error message and report `getline()` error
8bd6a67 Fix #114: Handle very long lines
47b1e1a Use _r thread safe functions when possible
0f5d883 Update daemon.c
f18e3ea Update doc, -T now disables all usage of threads
57aacbe Honor the -T flag when installing signal handlers

Cheers,
Jerry