Commit Graph

11 Commits (2a69f48541e0ed7fdf81fc88b079474331eeee76)

Author SHA1 Message Date
Will Norris 3ec5be3f51 all: remove AUTHORS file and references to it
This file was never truly necessary and has never actually been used in
the history of Tailscale's open source releases.

A Brief History of AUTHORS files
---

The AUTHORS file was a pattern developed at Google, originally for
Chromium, then adopted by Go and a bunch of other projects. The problem
was that Chromium originally had a copyright line only recognizing
Google as the copyright holder. Because Google (and most open source
projects) do not require copyright assignemnt for contributions, each
contributor maintains their copyright. Some large corporate contributors
then tried to add their own name to the copyright line in the LICENSE
file or in file headers. This quickly becomes unwieldy, and puts a
tremendous burden on anyone building on top of Chromium, since the
license requires that they keep all copyright lines intact.

The compromise was to create an AUTHORS file that would list all of the
copyright holders. The LICENSE file and source file headers would then
include that list by reference, listing the copyright holder as "The
Chromium Authors".

This also become cumbersome to simply keep the file up to date with a
high rate of new contributors. Plus it's not always obvious who the
copyright holder is. Sometimes it is the individual making the
contribution, but many times it may be their employer. There is no way
for the proejct maintainer to know.

Eventually, Google changed their policy to no longer recommend trying to
keep the AUTHORS file up to date proactively, and instead to only add to
it when requested: https://opensource.google/docs/releasing/authors.
They are also clear that:

> Adding contributors to the AUTHORS file is entirely within the
> project's discretion and has no implications for copyright ownership.

It was primarily added to appease a small number of large contributors
that insisted that they be recognized as copyright holders (which was
entirely their right to do). But it's not truly necessary, and not even
the most accurate way of identifying contributors and/or copyright
holders.

In practice, we've never added anyone to our AUTHORS file. It only lists
Tailscale, so it's not really serving any purpose. It also causes
confusion because Tailscalars put the "Tailscale Inc & AUTHORS" header
in other open source repos which don't actually have an AUTHORS file, so
it's ambiguous what that means.

Instead, we just acknowledge that the contributors to Tailscale (whoever
they are) are copyright holders for their individual contributions. We
also have the benefit of using the DCO (developercertificate.org) which
provides some additional certification of their right to make the
contribution.

The source file changes were purely mechanical with:

    git ls-files | xargs sed -i -e 's/\(Tailscale Inc &\) AUTHORS/\1 contributors/g'

Updates #cleanup

Change-Id: Ia101a4a3005adb9118051b3416f5a64a4a45987d
Signed-off-by: Will Norris <will@tailscale.com>
4 days ago
Alex Chan c2e474e729 all: rename variables with lowercase-l/uppercase-I
See http://go/no-ell

Signed-off-by: Alex Chan <alexc@tailscale.com>

Updates #cleanup

Change-Id: I8c976b51ce7a60f06315048b1920516129cc1d5d
2 months ago
Brad Fitzpatrick 1e2e319e7d util/slicesx: add MapKeys and MapValues from golang.org/x/exp/maps
Importing the ~deprecated golang.org/x/exp/maps as "xmaps" to not
shadow the std "maps" was getting ugly.

And using slices.Collect on an iterator is verbose & allocates more.

So copy (x)maps.Keys+Values into our slicesx package instead.

Updates #cleanup
Updates #12912
Updates #14514 (pulled out of that change)

Change-Id: I5e68d12729934de93cf4a9cd87c367645f86123a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Andrew Dunham 47b3476eb7 util/lru: add Clear method
Updates tailscale/corp#20109

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I751a669251a70f0134dd1540c19b274a97608a93
2 years ago
Brad Fitzpatrick 7c1d6e35a5 all: use Go 1.22 range-over-int
Updates #11058

Change-Id: I35e7ef9b90e83cac04ca93fd964ad00ed5b48430
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
David Anderson ed50f360db util/lru: update c.head when deleting the most recently used entry
Fixes tailscale/corp#14747

Signed-off-by: David Anderson <danderson@tailscale.com>
Co-authored-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
David Anderson 95082a8dde util/lru, util/limiter: add debug helper to dump state as HTML
For use in tsweb debug handlers, so that we can easily inspect cache
and limiter state when troubleshooting.

Updates tailscale/corp#3601

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
David Anderson 0909e90890 util/lru: replace container/list with a custom ring implementation
pre-generics container/list is quite unpleasant to use, and the pointer
manipulation operations for an LRU are simple enough to implement directly
now that we have generic types.

With this change, the LRU uses a ring (aka circularly linked list) rather
than a simple doubly-linked list as its internals, because the ring makes
list manipulation edge cases more regular: the only remaining edge case is
the transition between 0 and 1 elements, rather than also having to deal
specially with manipulating the first and last members of the list.

While the primary purpose was improved readability of the code, as it
turns out removing the indirection through an interface box also speeds
up the LRU:

       │ before.txt  │              after.txt              │
       │   sec/op    │   sec/op     vs base                │
LRU-32   67.05n ± 2%   59.73n ± 2%  -10.90% (p=0.000 n=20)

       │ before.txt │             after.txt              │
       │    B/op    │    B/op     vs base                │
LRU-32   21.00 ± 0%   10.00 ± 0%  -52.38% (p=0.000 n=20)

       │ before.txt │           after.txt            │
       │ allocs/op  │ allocs/op   vs base            │
LRU-32   0.000 ± 0%   0.000 ± 0%  ~ (p=1.000 n=20) ¹

Updates #cleanup

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
David Anderson 472eb6f6f5 util/lru: add a microbenchmark
The benchmark simulates an LRU being queries with uniformly random
inputs, in a set that's too large for the LRU, which should stress
the eviction codepath.

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
David Anderson 96c2cd2ada util/limiter: add a keyed token bucket rate limiter
Updates tailscale/corp#3601

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
Brad Fitzpatrick b0a984dc26 util/lru: add a package for a typed LRU cache
Updates tailscale/corp#7355

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago