- Complete the missing HTTP response codes / messages from :
 https://www.iana.org/assignments/http-status-codes/http-status-codes.xhtml

 patch from master@d686166ad469cad4043ed24328f4377e0d5f71a7

Switch the ctx and workspace to the req when resolving in pipe mode.

Fixes #3329
Fixes #3385

in VRT_priv_task() we asserted that only one of ctx->req and ctx->bo is
set when not in vcl_pipe {}, but we also need to extend that assertion
to when ctx->method == 0 after vcl_pipe as finished because
VRT_priv_task() could be called from director resolution.

Being at it, I also noticed that our behavior in vcl_pipe {} is
inconsistent as, from the shard director perspective, it is a backend
method. So now, vcl_pipe {} is handled like vcl_backend_* {}.

We still need to make up our mind about #3329 / #3330 and depending on
the outcome we might need to touch some places again which were changed
in this commit.

Fixes #3361

 Conflicts:
	doc/changes.rst
	lib/libvmod_directors/vmod.vcc
	lib/libvmod_directors/vmod_shard.c

 Conflicts:
	lib/libvmod_directors/vmod.vcc

 Conflicts:
	lib/libvmod_directors/vmod_shard.c

 Conflicts:
	lib/libvmod_directors/shard_dir.c
	lib/libvmod_directors/vmod_shard.c

from flexelint review

 Conflicts:
	lib/libvmod_directors/shard_dir.h

We implement weights by scaling the number of replicas of each backend.
The replicas parameter of .reconfigure() remains a minimum.

For existing vtcs, the Debug hashcircle output has been compared
before/after this change to ensure that behaviour is exactly equivalent.

For for wighted backends, it has been checked that the number of
instances per host on the hashcircle matches the expectation.

Also refactor and clean up some of the code:

- consistently make the number of ring points a uint32_t
- some constification

Ref #3276

 Conflicts:
	lib/libvmod_directors/shard_cfg.c
	lib/libvmod_directors/shard_dir.h
	lib/libvmod_directors/vmod.vcc

 Conflicts:
	lib/libvmod_directors/shard_dir.h
	lib/libvmod_directors/vmod_shard.c

dd28fc73Co-authored-by: Dridi Boukelmoune <dridi.boukelmoune@gmail.com>

Thank you, @Dridi

- yes, allocations outside the lock were motivated by minimizing the
  critical section, but n_backend could actually change, so this was
  wrong. As we use an RW lock, doing more work under it should only have
  marginal impact.

- n_backend == 0 is probably best handled as a special case

With that, (almost) only libvgz carries goto statements from zlib.

This isn't changing any of the previous semantics, in particular the
AN(be) assertion from the "ok:" jump is honored by all code paths
formerly leading to it.

Previously, the bitmap was allocated on the stack prior to the magic
check of shardd, which is now fixed at the expense of a potential code
style violation. But more importantly, we currently read the number of
backends prior to acquiring the read lock, but there is no evidence
that this was done on purpose and not overlooked, besides moving a
possibly expensive state initialization outside of the critical
section.

If that was on purpose, please document it.

ebbbad96Co-authored-by: Poul-Henning Kamp <phk@FreeBSD.org>

This reverts commit 0e32f166.

 Conflicts:
	bin/varnishd/http2/cache_http2_deliver.c

This came from the H2 backport c3902d57
Fixes #3382

For VCL_TIME values that would convert to a year element that can not fit
in an int, gmtime_r would fail, and VTIM_format() would use random stack
values when picking weekday and month strings.

This patch changes VTIM_format to return "" when gmtime_r reports
failures. This way the API is not changed. Callers can test for empty
string to catch the failure if needed.

VRT_TIME_string is patched to catch the VTIM_format error, and return NULL
on failure.

Fixes: #3308

since d4b6228e the busyobj might also
gain one, so depending on who deref's first, there may be one or zero
references left.

With this patch fetch threads will for completely cached request bodies
keep a reference to it for the entire duration of the fetch. This extends
the retry window of backend requests with request body beyond the
BOS_REQ_DONE point.

Patch by: Poul-Henning Kamp

Currently we allow fetch retries with body even after we have released the
request that initiated the fetch, and the request body with it. The
attached test case demonstrates this, where s2 on the retry attempt gets
stuck waiting for 3 bytes of body data that is never sent.

Fix this by keeping track of what the initial request body status was, and
failing the retry attempt if the request was already released
(BOS_REQ_DONE) and the request body was not cached.

Conflicts:
    bin/varnishd/cache/cache.h

This reverts commit b9050923.

 Conflicts:
	bin/varnishd/cache/cache_esi_fetch.c
	bin/varnishd/cache/cache_fetch.c

Previously, we only checked `v1l->deadline` (which gets initialized
from the `send_timeout` session attribute or parameter) only for short
writes, so for successful "dripping" http1 writes (streaming from a
backend busy object with small chunks), we did not respect the
timeout.

This patch restructures `V1L_Flush()` to always check the deadline
before a write by turning a `while() { ... }` into a `do { ... }
while` with the same continuation criteria: `while (i != v1l->liov)`
is turned into `if (i == v1l->liov) break;` and `while (i > 0 || errno
== EWOULDBLOCK)` is kept to retry short writes.

This also reduces the `writev()` call sites to one.

Fixes #3189

 Conflicts:
	bin/varnishd/http1/cache_http1_line.c
	bin/varnishtest/tests/s00011.vtc