Similarly to 40e8ce405859 in the stream module, this reduces the time
accept mutex is held. This also simplifies following changes to
introduce PROXY protocol support.
If we need to be notified about further events, ngx_handle_read_event()
needs to be called after a read event is processed. Without this,
an event can be removed from the kernel and won't be reported again,
notably when using oneshot event methods, such as eventport on Solaris.
For consistency, existing ngx_handle_read_event() call removed from
ngx_mail_read_command(), as this call only covers one of the code paths
where ngx_mail_read_command() returns NGX_AGAIN. Instead, appropriate
processing added to the callers, covering all code paths where NGX_AGAIN
is returned.
As long as a read event is blocked (ignored), ngx_handle_read_event()
needs to be called to make sure no further notifications will be
triggered when using level-triggered event methods, such as select() or
poll().
The "!rev->ready" test seems to be a typo, introduced in the original
commit (719:f30b1a75fd3b). The ngx_handle_write_event() code properly
tests for "rev->ready" instead.
Due to this typo, read events might be unexpectedly removed during
proxying after an event on the other part of the proxied connection.
Catched by mail proxying tests.
The strerrordesc_np() function, introduced in glibc 2.32, provides an
async-signal-safe way to obtain error messages. This makes it possible
to avoid copying error messages.
Previously, systems without sys_nerr (or _sys_nerr) were handled with an
assumption that errors start at 0 and continuous. This is, however, not
something POSIX requires, and not true on some platforms.
Notably, on Linux, where sys_nerr is no longer available for newly linked
binaries starting with glibc 2.32, there are gaps in error list, which
used to stop us from properly detecting maximum errno. Further, on
GNU/Hurd errors start at 0x40000001.
With this change, maximum errno detection is moved to the runtime code,
now able to ignore gaps, and also detects the first error if needed.
This fixes observed "Unknown error" messages as seen on Linux with
glibc 2.32 and on GNU/Hurd.
With this change, behaviour of HTTP/2 becomes even closer to HTTP/1.x,
and client_header_timeout instead of keepalive_timeout is used before
the first request is received.
This fixes HTTP/2 connections being closed even before the first request
if "keepalive_timeout 0;" was used in the configuration; the problem
appeared in f790816a0e87 (1.19.7).
Using default highlighting makes it possible to easily overrule
highlighting specified in the syntax file, see ":highlight-default"
in vim help for details.
As per quic-transport-34:
An endpoint also restarts its idle timer when sending an ack-eliciting
packet if no other ack-eliciting packets have been sent since last receiving
and processing a packet.
Previously, the timer was set for any packet.
The structure is used to parse an HTTP/3 request. An object of this type is
added to ngx_http_request_t instead of h3_parse generic pointer.
Also, the new field is located outside of the request ephemeral zone to keep it
safe after request headers are parsed.
Previously, PINGs and other frames extended possible keepalive time,
making it possible to keep an open HTTP/2 connection for a long time.
Now the connection is always closed as long as keepalive_timeout expires,
similarly to how it happens in HTTP/1.x.
Note that as a part of this change, incomplete frames are no longer
trigger a separate timeout, so http2_recv_timeout (replaced by
client_header_timeout in previous patches) is essentially cancelled.
The client_header_timeout is, however, used for SSL handshake and
while reading HEADERS frames.
Instead, keepalive_timeout and keepalive_requests are now used. This
is expected to simplify HTTP/2 code and usage. This also matches
directives used by upstream module for all protocols.
In case of default settings, this effectively changes maximum number
of requests per connection from 1000 to 100. This looks acceptable,
especially given that HTTP/2 code now properly supports lingering close.
Further, this changes default keepalive timeout in HTTP/2 from 300 seconds
to 75 seconds. This also looks acceptable, and larger than PING interval
used by Firefox (network.http.spdy.ping-threshold defaults to 58s),
the only browser to use PINGs.
Instead, the client_header_timeout is now used for HTTP/2 reading.
Further, the timeout is changed to be set once till no further data
left to read, similarly to how client_header_timeout is used in other
places.
New connections are marked reusable by ngx_http_init_connection() if there
are no data available for reading. As a result, if SSL is not used,
ngx_http_v2_init() might be called when the connection is marked reusable.
If a HEADERS frame is immediately available for reading, this resulted
in connection being preserved in reusable state with an active request,
and possibly closed later as if during worker shutdown (that is, after
all active requests were finalized).
Fix is to explicitly mark connections non-reusable in ngx_http_v2_init()
instead of (incorrectly) assuming they are already non-reusable.
Found by Sergey Kandaurov.
If ngx_drain_connections() fails to immediately reuse any connections
and there are no free connections, it now additionally tries to reuse
a connection again. This helps to provide at least one free connection
in case of HTTP/2 with lingering close, where merely trying to reuse
a connection once does not free it, but makes it reusable again,
waiting for lingering close.
This is particularly important in HTTP/2, where keepalive connections
are closed with lingering. Before the patch, reusing a keepalive HTTP/2
connection resulted in the connection waiting for lingering close to
remain in the reusable connections queue, preventing ngx_drain_connections()
from closing additional connections.
The patch fixes it by marking the connection reusable again, and so
moving it in the reusable connections queue. Further, it makes actually
possible to reuse such connections if needed.
The "max_ack_delay", "ack_delay_exponent", and "max_udp_payload_size"
transport parameters were not communicated to client.
The "disable_active_migration" and "active_connection_id_limit"
parameters were not saved into zero-rtt context.
18.1. Reserved Transport Parameters
Transport parameters with an identifier of the form "31 * N + 27" for
integer values of N are reserved to exercise the requirement that
unknown transport parameters be ignored. These transport parameters
have no semantics, and can carry arbitrary values.
Setting the timer is brought into compliance with quic-recovery-34. Now it's
set from a single function ngx_quic_set_lost_timer() that takes into account
both loss detection and PTO. The following issues are fixed with this change:
- when in loss detection mode, discarding a context could turn off the
timer forever after switching to the PTO mode
- when in loss detection mode, sending a packet resulted in rescheduling the
timer as if it's always in the PTO mode
As per quic-transport-33:
An endpoint MUST acknowledge all ack-eliciting Initial and Handshake
packets immediately
If a packet carrying Initial or Handshake ACK was lost, a non-immediate ACK
should not be sent later. Instead, client is expected to send a new packet
to acknowledge.
Sending non-immediate ACKs for Initial packets can cause the client to
generate an inflated RTT sample.
The token generation in QUIC is reworked. Single host key is used to generate
all required keys of needed sizes using HKDF.
The "quic_stateless_reset_token_key" directive is removed. Instead, the
"quic_host_key" directive is used, which reads key from file, or sets it
to random bytes if not specified.
The flag was introduced to create type-aware CONNECTION_CLOSE frames,
and now is replaced with frame type information, directly accessible.
Notably, this fixes type logging for received frames in b3d9e57d0f62.
The flag is used in ngx_http_finalize_connection() to switch client connection
to the keepalive mode. Since eaea7dac3292 this code is not executed for HTTP/3
which allows us to revert the change and get back to the default branch code.
This part somehow slipped away from c5840ca2063d.
While it is not expected to be needed in case of lingering close,
it is good to keep it for correctness (see 2b5528023f6b).
