No sense downloading articles we're just going to toss out the next time
we performance msgbase maintenance.

... which simplifies the fmutex_close() function and signature.

By default, the duration is infinite, but some sysops may not want this
file to be ever-grower but rather periodically pruned by the new trashman
utility.

Sysop that don't use spambait.cfg won't benefit from this change.

Also, don't get hostname unless we're surely going to write to the file.

The 'atomic_remove' argument isn't used in non-Windows builds since we can
remove() before close() on non-Windows OSes already.

I managed to hit a bug where bseen and seen were both completely
filled.  No idea how I hit it, so not positive it's fixed.

This is cheap insurance against the 43k file groung to 1.6MB for
someone else.

1) Cache the binified seen data rather than regenerate every time
2) Only call js.gc() after a complete fetch or store loop

O_EXCL doesn't appear to be working very reliably over Samba, so let's add
file locking to the equation.

glob() results might be out of date by the time we look at each file, just
skip missing QWK pack semaphore files silently. This should resolve the
".now already gone" messages too. Hopefully.

Removed some extraneous quotes around logged event command-lines.

Also when detecting a blocked event_thread, log the event_code that is/was
running last.

Should be no functional change.

Also, make save_cfg() require that the lock be held.

This should now actually work properly.
Also, add a debug_exceptions flag to rethrow exceptions so I can
get line numbers.

It shouldn't though.

Also, always use full_send(), not the socket send.

This removes unnecessary some cruft and complexity, most especially from the
event_thread().

Using sbbs_t::fremove() instead of remove(). This probably resolves some
Coverity issues where we weren't checking the return value.

ENOENT = "No such file or directory"

Passing 'true' for the optional 'log_all_errors' parameter overrides this
(logs all errors, including ENOENT).

Only log message header read error if the msgbase.status is non-zero

Don't try to import anything if the stop semfile is signaled while
exporting.

Increment revision to 1.2

Add log message when spawning background timed event

Only log messages about QWK mutex files existing when > 60 seconds old

First, fix the logged username bug in the "Lock exists" log message.
Next, double check that the trigger file (sem file or REP file) still exists
after acquiring the file mutex.

Use a temp varible (fname) to make the code easier to read.

Also, after grabbing a lock, enter a try/catch that will unlock
and re-throw the error.

Vertrauen's FTP server gets abused by QWKnet logins sometimes and handling
the race conditions around QWK packet creation attempts is silly - there's
no legit reason why a QWKnet account needs to be logged-in multiple times
concurrently to the hub's FTP server, so reject the subsequent logins even
when they're on different hosts (as is the case with Vertrauen).

As part of this change:
- fmutex() now takes an new time_t* argument to (optionally) store the
  time of the mutex file for helping logging (locked since when?).
- time_as_hhmm() created to format a string as either HH:MM or HH:MM[a|p]
  (depending on system configuration for 12 or 24 hour time formatting).
- renamed the old hhmmtostr ()to tm_as_hhmm() (since it takes a struct tm arg)
  and have it return a non-padded string (useful in more situations without
  requiring truncation) when the sysop prefers 24-hour time.

Pretty remedial option parsing here, the order is significant

It looks like this has been a long-standing UIFC bug (pre-3.0)

If a uifc list that can scroll is showing the bottom-most line,
and an option that is not the last is deleted, and both *cur and
*bar are left untouched, *bar would be adjusted to be too high,
resulting in various highlight bar corruption issues.

This commit just rewrites that logic to be comprehensible, and
ensures that if bar is set such that the list would end before the
bottom of the window, it gets moved up.  This makes delete do the
right thing (didn't test with insert, that may do weird things).

Also, since I figured out a good definition of what bar actually
represtens, add a comment to that effect.