They're not defined to be, though we've not seen this on Linux (testing
showed that it is page-level atomic, which means it can still happen across
page boundaries though!). This was pointed out by whitslack in
https://github.com/ElementsProject/lightning/issues/4288
In practice, this just means not complaining when it happens, and also
not trying to get tricky to use it on MacOS (we can safely seek & write,
since we're single-threaded).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Removed: Removed bogus UNUSUAL log about gossip_store 'short test'.
We should actually be including this (as it may define _GNU_SOURCE
etc) before any system headers. But where we include <assert.h> we
often didn't, because check-includes would complain that the headers
included it too.
Weaken that check, and include config.h in C files before assert.h.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This avoids overwriting the ones in git, and generally makes things neater.
We have convenience headers wire/peer_wire.h and wire/onion_wire.h to
avoid most #ifdefs: simply include those.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This happened on Travis, and the gossip_store was a suspicious 4096
bytes long. This implies they're using some non-atomic filesystem
(gossipd always does atomic writes to gossip_store), but if they are,
others surely are too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I decided to try a faster implementation, only to find our crc32c was
not correct! Ouch.
I removed the crc32c functions from ccan/crc, and added a new crc32c
module which has the Mark Adler x86-64-optimized variants.
We bump gossip_store version again, since csums have changed.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This means we intercept the peer's gossip_timestamp_filter request
in the per-peer subdaemon itself. The rest of the semantics are fairly
simple however.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
(We don't increment the gossip_store version, since there are only a
few commits since the last time we did this).
This lets the reader simply filter messages; this is especially nice since
the channel_announcement timestamp is *derived*, not in the actual message.
This also creates a 'struct gossip_hdr' which makes the code a bit
clearer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Keeping the uintmap ordering all the broadcastable messages is expensive:
130MB for the million-channels project. But now we delete obsolete entries
from the store, we can have the per-peer daemons simply read that sequentially
and stream the gossip itself.
This is the most primitive version, where all gossip is streamed;
successive patches will bring back proper handling of timestamp filtering
and initial_routing_sync.
We add a gossip_state field to track what's happening with our gossip
streaming: it's initialized in gossipd, and currently always set, but
once we handle timestamps the per-peer daemon may do it when the first
filter is sent.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We use the high bit of the length field: this way we can still check
that the checksums are valid on deleted fields.
Once this is done, serially reading the gossip_store file will result
in a complete, ordered, minimal gossip broadcast. Also, the horrible
corner case where we might try to delete things from the store during
load time is completely gone: we only load non-deleted things.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell