On normal systems, triggering a timeout should be a bug in code or
configuration error, so I do not think we should extend the default
timeout. Also, we should not introduce a 'first class' configuration
option about that. But, making it configurable may be useful for cases
such that "an extremely highly utilized system (lots of OOM kills,
very high CPU utilization, etc)".
Closes#25441.
Then, timout_compare() becomes simplar, the timeout value becomes
consistent with what sd_netlink_get_timeout() provides.
This also drop unnecessary assignment of reply_callback.timeout after
the slot is dropped from the prioq.
Doesn't really matter since the two unicode symbols are supposedly
equivalent, but let's better follow the unicode recommendations to
prefer greek small letter mu, as per:
https://www.unicode.org/reports/tr25
-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.
Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state
Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.
In some places, initialization is dropped if unnecessary.
This effectively reverts 84e1001541.
The sd-netlink library has several issues, and we should not export it
without solving them. See issues #24258 and #24124.
We have RxBufferSize= and TxBufferSize= in .link files. Let's use the same
abbreviation here. OTOH, "inc" could be short for "increment" or "increase",
let's avoid that.
It was added originally in 65f568bbeb. The API is
has stabilized pretty much, and generally follows the usual style for
libsystemd. We've held it as a public-but-private library for almost 10 years,
let's export it.
sd_netlink_sendv() and sd_nfnl_nft_*() are excluded.
libsystemd.so seems to grow by 12k.
Kernel manages each genl family by its name, e.g. "nlctrl" or WG_GENL_NAME,
and its ID (used for nlmsg_type) is determined dynamically when the
corresponding module is loaded.
This commit makes sd-netlink follow the same way; now, sd_genl_family_t
is dropped, and sd_genl_message_new() takes a genl family name. Each
genl family is resolved when it is used first time, and its information
is stored in GenericNetlinkFamily.
We recently started making more use of malloc_usable_size() and rely on
it (see the string_erase() story). Given that we don't really support
sytems where malloc_usable_size() cannot be trusted beyond statistics
anyway, let's go fully in and rework GREEDY_REALLOC() on top of it:
instead of passing around and maintaining the currenly allocated size
everywhere, let's just derive it automatically from
malloc_usable_size().
I am mostly after this for the simplicity this brings. It also brings
minor efficiency improvements I guess, but things become so much nicer
to look at if we can avoid these allocation size variables everywhere.
Note that the malloc_usable_size() man page says relying on it wasn't
"good programming practice", but I think it does this for reasons that
don't apply here: the greedy realloc logic specifically doesn't rely on
the returned extra size, beyond the fact that it is equal or larger than
what was requested.
(This commit was supposed to be a quick patch btw, but apparently we use
the greedy realloc stuff quite a bit across the codebase, so this ends
up touching *a*lot* of code.)
This drops the "const" specifier from the opaque object parameters to
various functions in our API.
This effectively reverts #19292 and more.
Why drop this? Our public APIs should not leak too much information
about how stuff is implemented internally. In our public APIs we
shouldn't give too many guarantees we don#t want to necessarily keep.
Specifically: in many cases it makes sense that getters actually
generate/parse/allocate data on the fly, storing/caching the result
internally, to speed things up, do things lazily or to track memory
allocations so that they can be freed later. Doing this means we need to
change the objects, even though the getters are semantically a read
operation.
We want to retain the freedom that we can change things around
internally. By exposing the objects as "const" we remove a good chunk of
that, for little gain.
See sd_bus_creds_get_description() for a real example of a getter that
implicitly caches and thus modifies the relevant object.
This removes the "const" decorators from sd-dhcp and sd-netlink, two
APIs that we intend to make public eventually even though they still are
not, leaving us the chance to still fix this before it becomes set in
stone.
Let's use uint32_t everywhere to maintain the seqno, since that's what
the kernel does. Prviously in the reply_callback logic we used 64bit,
for no apparent reason.
Using 32bit also provides us with the benefit that we can avoid using
uint64_hash_ops, and can use trivial_hash_ops instead for the reply
hashmap, so that we can store the seqno in the key pointer directly.
While we are at it, let's make sure we never run into serial collisions
internally (32bit is a lot, but not that much), and let's put a limit on
outstanding serials, to catch programming errors.
Will be used by nftables nfnetlink backend.
It sends a series of netlink messages that form a nftables
update transaction.
The transaction will then generate a series of ack messages
(or an error).
This function will be used to read these acks.
nftables uses a transaction-based netlink model: one netlink write
comes with multiple messages.
A 'BEGIN' message to tell nf_tables/kernel that a new transaction starts.
Then, one more messages to add/delete tables/chains/rules etc.
Lastly, an END message that commits all changes.
This function will be used to send all the individual messages that should
make up a single transaction as a single write.
Lennart Poettering
Yu Watanabe
Zbigniew Jędrzejewski-Szmek
David Tardon
Florian Westphal