New connection filter `cf-dns` that manages DNS queries. If hands
out addresses and HTTPS-RR records to anyone interested. Used by
HTTPS and IP happy eyeballing.
Information may become available *before* the libcurl "dns entry"
is complete, e.g. all queries have been answered. The cf-ip-happy
filter uses this information to start connection attempts as soon
as the first address is available.
The multi MSTATE_RESOLVING was removed. A new connection always
goes to MSTATE_CONNECTING. The connectdata bit `dns_resolved`
indicates when DNS information is complete. This is used for
error reporting and starting the progress meter.
Removed dns entries `data->state.dns[i]`, as the `cf-dns` filter
now keeps the reference now.
Many minor tweaks for making this work and pass address information
around safely.
Closes#21027
- drop stray duplicate empty lines in docs, scripts, test data, include,
examples, tests.
- drop duplicate PP parenthesis.
- curl-functions.m4: move literals to the right side in if expressions,
to match rest of the source code.
- FAQ.md: delete language designator from an URL.
- packages: apply clang-format (OS400, VMS).
- scripts/schemetable.c: apply clang-format.
- data320: delete duplicate empty line that doesn't change the outcome.
- spacecheck: extend to check for duplicate empty lines
(with exceptions.)
- fix whitespace nits
Closes#19936
The `struct Curl_dns_entry *` used to established a connection
do not have the connection's lifetime, but the transfer's lifetime
(of the transfer that initiates the connect).
`Curl_dns_entry *` is reference counted with the "dns cache". That
cache might be owned by the multi or the transfer's share. In the
share, the reference count needs updating under lock.
Therefore, the dns entry can only be kept *and* released using the
same transfer it was initially looked up from. But a connection is
often discarded using another transfer.
So far, the problem of this has been avoided in clearing the connection's
dns entries in the "multi_don()" handling. So, connections had NULL
dns entries after the initial transfers and its connect had been handled.
Keeping the dns entries in data->state seems therefore a better choice.
Also: remove the `struct Curl_dns_entry *` from the connect filters
contexts. Use `data->state.dns` every time instead and fail correctly
when not present and needed.
Closes#17383
lib : remove all hyper code
configure: stop detecting hyper
docs: no more mention of hyper
tests: mo more special-handling of hyper builds
CI: no jobs using hyper
Closes#15120
