Upgrading staticcheck upgraded golang.org/x/sync
(one downside of mixing our tools in with our regular go.mod),
which introduced a new dependency via
https://go-review.googlesource.com/c/sync/+/251677
That CL could and probably should be written without runtime/debug,
but it's not clear to me that that is better at this moment
than simply accepting the additional package as a dependency.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Add content length hints to headers.
The server can use these hints to more efficiently select buffers.
Stop attempting to compress tiny requests.
The bandwidth savings are negligible (and sometimes negative!),
and it makes extra work for the server.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The cornerstone API is a more memory-efficient Unmarshal.
The savings come from re-using a json.Decoder.
BenchmarkUnmarshal-8 4016418 288 ns/op 8 B/op 1 allocs/op
BenchmarkStdUnmarshal-8 4189261 283 ns/op 184 B/op 2 allocs/op
It also includes a Bytes type to reduce allocations
when unmarshalling a non-hex-encoded JSON string into a []byte.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
likelyHomeRouterIPDarwinSyscall iterates through the list of routes,
looking for a private gateway, returning the first one it finds.
likelyHomeRouterIPDarwinExec does the same thing,
except that it returns the last one it finds.
As a result, when there are multiple gateways,
TestLikelyHomeRouterIPSyscallExec fails.
(At least, I think that that is what is happening;
I am going inferring from observed behavior.)
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The compiler is failing to draw the connection between
slice cap and slice len, so is missing some obvious BCE opportunities.
Give it a hint by making the cap equal to the length.
The generated code is smaller and cleaner, and a bit faster.
name old time/op new time/op delta
Decode/tcp4-8 12.2ns ± 1% 11.6ns ± 3% -5.31% (p=0.000 n=28+29)
Decode/tcp6-8 12.5ns ± 2% 11.9ns ± 2% -4.84% (p=0.000 n=30+30)
Decode/udp4-8 11.5ns ± 1% 11.1ns ± 1% -3.11% (p=0.000 n=25+24)
Decode/udp6-8 11.8ns ± 3% 11.4ns ± 1% -3.08% (p=0.000 n=30+26)
Decode/icmp4-8 11.0ns ± 3% 10.6ns ± 1% -3.38% (p=0.000 n=25+30)
Decode/icmp6-8 11.4ns ± 1% 11.1ns ± 2% -2.29% (p=0.000 n=27+30)
Decode/igmp-8 10.3ns ± 0% 10.0ns ± 1% -3.26% (p=0.000 n=19+23)
Decode/unknown-8 8.68ns ± 1% 8.38ns ± 1% -3.55% (p=0.000 n=28+29)
Part of #19.
name old time/op new time/op delta
Filter/icmp4-8 32.2ns ± 3% 32.5ns ± 2% ~ (p=0.524 n=10+8)
Filter/icmp6-8 49.7ns ± 6% 43.1ns ± 4% -13.12% (p=0.000 n=9+10)
Signed-off-by: David Anderson <danderson@tailscale.com>
This lets servers using tsweb register expvars
that will track the number of requests ending
in 200s/300s/400s/500s.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This makes it easy to compact slices that contain duplicate elements
by sorting and then uniqing.
This is an alternative to constructing an intermediate map
and then extracting elements from it. It also provides
more control over equality than using a map key does.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
When the network link changes, existing UDP sockets fail immediately
and permanently on macOS.
The forwarder set up a single UDP conn and never changed it.
As a result, any time there was a network link change,
all forwarded DNS queries failed.
To fix this, create a new connection when send requests
fail because of network unreachability.
This change is darwin-only, although extended it to other platforms
should be straightforward.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
While we're here, parseQuery into a plain function.
This is helpful for fuzzing. (Which I did a bit of. Didn't find anything.)
And clean up a few minor things.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
I had to use
go get -u github.com/tailscale/depaware@e09ee10c18249e4bf198e66bbd47babcd502637a
to force it to the correct version; it kept selecting head~1.
Maybe because the branch is called main instead of master?
Maybe because of some delay?
Updates #654. See that issue for a discussion of why
this timeout reduces flakiness, and what next steps are.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This Clone function knows how to clone any types
for which it has generated Clone methods.
This allows callers to efficiently clone
an inbound interface{} that might contain one of these types.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This was causing any type to be reported as found,
as long as there were any type decls at all. Oops.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
If you change a struct and don't re-run cloner,
your Cloner method might be inaccurate, leading to bad things.
To prevent this, write out the struct as it is at the moment that
cloner is caller, and attempt a conversion from that type.
If the struct gets changed in any way, this conversion will fail.
This will yield false positives: If you change a non-pointer field,
you will be forced to re-run cloner, even though the actual generated
code won't change. I think this is an acceptable cost: It is a minor
annoyance, which will prevent real bugs.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Running tailscaled on my machine yields lots of entries like:
weird: missing {tcp 6060}
parsePortsNetstat is filtering out loopback addresses as uninteresting.
Then addProcesses is surprised to discover these listening ports,
which results in spurious logging.
Teach addProcesses to also ignore loopback addresses.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This will make it easier for a human to tell what
version is deployed, for (say) correlating line numbers
in profiles or panics to corresponding source code.
It'll also let us observe version changes in prometheus.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
