double quotes ourselves.

FreeBSD's code is undergoing some compatibility adaptations
so we go directly to the source from here.

PS: Please keep cochinelle out of libvgz.

Until now we'd send a zero-length DATA frame with the END_STREAM flag
set, masquerading fetch streaming failures as completed responses. In
the absence of a content-length header a user agent couldn't notice
there was a problem.

This does not apply to ESI sub-requests, they aren't streamed during
delivery.

Since the removal of dry signals, pools will spin when they run out of
threads and increment MAIN.threads_limited at a very high rate. That
spike in CPU consumption will also have detrimental effects on useful
tasks.

This change introduces a 1s delay when the pool is saturated. This
allows to periodically exercise the watchdog check. We could wait until
the watchdog times out but we would also miss potential updates to the
thread_pool_watchdog parameter.

To avoid spurious increments of MAIN.threads_limited we only take task
submissions into account and ignore timeouts of the condvar.

Refs #2942
Refs #3531

it was already accepted on Solaris and NetBSD, now we have seen it on
Linux and I think it does not make sense to keep the exception for
Apple.

Fixes #3532 (hopefully)

Spotted by: Rasmus Villemoes

Spotted by: Rasmus Villemoes

Spotted by: Rasmus Villemoes

Spotted by: Rasmus Villemoes

like the sign is wrong, we should never get EINVAL if the deadline is
in the future.

Fix the test to make sense, and hope for the best (or a M1 :-)

Spotted by: Rasmus Villemoes

Spotted by:	Rasmus Villemoes

Move the description of this feature from user to reference.

In pool_herder(), we do as much work as possible outside the pool
mutex. In particular, we check if we need to breed more threads, then
we do more checks, and finally we aquire the lock and either go sleep
or increase the threads_limited counter if, at that point, lqueue is
non-zero.

Yet it could have increased since we last checked, and there is
nothing wrong with that, we will breed a new thread in the next
iteration of the loop.

Increase threads_limited only if we would not bread a new thread right
away.

Fixes #3531

to handle correctly use of the "gunzip" filter at esi_level > 0

Fixes #3529

The bo fields err_code and err_reason need to be reset on a retry otherwise the values are kept.

Fixes #3525

suggested by phk

7ec28f1a did not work with object
methods because we need a partial symbol table lookup to identify them,
otherwise the symbol kind we find is just SUB for the method's return
value.

Additions to the test case and vmod_debug by @slimhazard, thank you

Fixes #3521

For the next commit, we need a partial lookup without error.

Alternatively, we could also a an error mode.

Diff best viewed with -b option

- avoid the second call to VCC_SymbolGet(), unless necessary
- reorder from simple to complex

Ref 7ec28f1a