This option was deprecated in 5a922dc162bbe0a03450165da4e6aceca55073d4, which
is part of the v24.0.0 release, so we can remove it from master.

This patch;

- adds a check to ValidatePlatformConfig, and produces a fatal error
  if oom-score-adjust is set
- removes the deprecated libcontainerd/supervisor.WithOOMScore
- removes the warning from docker info

With this patch:

    dockerd --oom-score-adjust=-500 --validate
    Flag --oom-score-adjust has been deprecated, and will be removed in the next release.
    unable to configure the Docker daemon with file /etc/docker/daemon.json: merged configuration validation from file and command line flags failed: DEPRECATED: The "oom-score-adjust" config parameter and the dockerd "--oom-score-adjust" options have been removed.

And when using `daemon.json`:

    dockerd --validate
    unable to configure the Docker daemon with file /etc/docker/daemon.json: merged configuration validation from file and command line flags failed: DEPRECATED: The "oom-score-adjust" config parameter and the dockerd "--oom-score-adjust" options have been removed.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cmd/dockerd: gracefully shut down the API server

As of Go 1.8, "net/http".Server provides facilities to close all
listeners, making the same facilities in server.Server redundant.
http.Server also improves upon server.Server by additionally providing a
facility to also wait for outstanding requests to complete after closing
all listeners. Leverage those facilities to give in-flight requests up
to five seconds to finish up after all containers have been shut down.

Signed-off-by: Cory Snider <csnider@mirantis.com>

Logging through a dependency-injected interface value was a vestige of
when Trap was in pkg/signal to avoid importing logrus in a reusable
package: cc4da8112814cdbb00dbf23370f9ed764383de1f.
Now that Trap lives under cmd/dockerd, nobody will be importing this so
we no longer need to worry about minimizing the package's dependencies.

Signed-off-by: Cory Snider <csnider@mirantis.com>

Always calling os.Exit() on clean shutdown may not always be desirable
as deferred functions are not run. Let the cleanup callback decide
whether or not to call os.Exit() itself. Allow the process to exit the
normal way, by returning from func main().

Simplify the trap.Trap implementation. The signal notifications are
buffered in a channel so there is little need to spawn a new goroutine
for each received signal. With all signals being handled in the same
goroutine, there are no longer any concurrency concerns around the
interrupt counter.

Signed-off-by: Cory Snider <csnider@mirantis.com>

The image store sends events when a new image is created/tagged, using
it instead of the reference store makes sure we send the "tag" event
when a new image is built using buildx.

Signed-off-by: Djordje Lukic <djordje.lukic@docker.com>

The fix to ignore SIGPIPE signals was originally added in the Go 1.4
era. signal.Ignore was first added in Go 1.5.

Signed-off-by: Cory Snider <csnider@mirantis.com>

daemon: deprecate --oom-score-adjust for the daemon

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

The `oom-score-adjust` option was added in a894aec8d81de5484152a76d76b80809df9edd71,
to prevent the daemon from being OOM-killed before other processes. This
option was mostly added as a "convenience", as running the daemon as a
systemd unit was not yet common.

Having the daemon set its own limits is not best-practice, and something
better handled by the process-manager starting the daemon.

Commit cf7a5be0f2ee8bb4a3f7961682e13b89bc625299 fixed this option to allow
disabling it, and 2b8e68ef06ca3daf2b0e17e51ba72999773b6270 removed the default
score adjust.

This patch deprecates the option altogether, recommending users to set these
limits through the process manager used, such as the "OOMScoreAdjust" option
in systemd units.

With this patch:

    dockerd --oom-score-adjust=-500 --validate
    Flag --oom-score-adjust has been deprecated, and will be removed in the next release.
    configuration OK

    echo '{"oom-score-adjust":-500}' > /etc/docker/daemon.json
    dockerd
    INFO[2023-04-12T21:34:51.133389627Z] Starting up
    INFO[2023-04-12T21:34:51.135607544Z] containerd not running, starting managed containerd
    WARN[2023-04-12T21:34:51.135629086Z] DEPRECATED: The "oom-score-adjust" config parameter and the dockerd "--oom-score-adjust" option will be removed in the next release.

    docker info
    Client:
      Context:    default
      Debug Mode: false
    ...
    DEPRECATED: The "oom-score-adjust" config parameter and the dockerd "--oom-score-adjust" option will be removed in the next release

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>