These network operations really don't have anything to do with the
container but rather are setting up the networking.
Ideally these wouldn't get shoved into the daemon package, but doing
something else (e.g. extract a network service into a new package) but
there's a lot more work to do in that regard.
In reality, this probably simplifies some of that work as it moves all
the network operations to the same place.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
1. As daemon.ContainerStop() documentation says,
> If a negative number of seconds is given, ContainerStop
> will wait for a graceful termination.
but since commit cfdf84d5d0 (PR #32237) this is no longer the case.
This happens because `context.WithTimeout(ctx, timeout)` is implemented
as `WithDeadline(ctx, time.Now().Add(timeout))`, resulting in a deadline
which is in the past.
To fix, don't use WithDeadline() if the timeout is negative.
2. Add a test case to validate the correct behavior and
as a means to prevent a similar regression in the future.
3. Fix/improve daemon.ContainerStop() and client.ContainerStop()
description for clarity and completeness.
4. Fix/improve DefaultStopTimeout description.
Fixes: cfdf84d5d0 ("Update Container Wait")
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Since Go 1.7, context is a standard package. Since Go 1.9, everything
that is provided by "x/net/context" is a couple of type aliases to
types in "context".
Many vendored packages still use x/net/context, so vendor entry remains
for now.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The unit test is checking that setting of non-default StopTimeout
works, but it checked the value of StopSignal instead.
Amazingly, the test was working since the default StopSignal is SIGTERM,
which has the numeric value of 15.
Fixes: commit e66d21089 ("Add config parameter to change ...")
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This moves the platform specific stuff in a separate package and keeps
the `volume` package and the defined interfaces light to import.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Commit 7a7357dae1 ("LCOW: Implemented support for docker cp + build")
changed `container.BaseFS` from being a string (that could be empty but
can't lead to nil pointer dereference) to containerfs.ContainerFS,
which could be be `nil` and so nil dereference is at least theoretically
possible, which leads to panic (i.e. engine crashes).
Such a panic can be avoided by carefully analysing the source code in all
the places that dereference a variable, to make the variable can't be nil.
Practically, this analisys are impossible as code is constantly
evolving.
Still, we need to avoid panics and crashes. A good way to do so is to
explicitly check that a variable is non-nil, returning an error
otherwise. Even in case such a check looks absolutely redundant,
further changes to the code might make it useful, and having an
extra check is not a big price to pay to avoid a panic.
This commit adds such checks for all the places where it is not obvious
that container.BaseFS is not nil (which in this case means we do not
call daemon.Mount() a few lines earlier).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Signed-off-by: John Howard <jhoward@microsoft.com>
While debugging #32838, it was found (https://github.com/moby/moby/issues/32838#issuecomment-356005845) that the utility VM in some circumstances was crashing. Unfortunately, this was silently thrown away, and as far as the build step (also applies to docker run) was concerned, the exit code was zero and the error was thrown away. Windows containers operate differently to containers on Linux, and there can be legitimate system errors during container shutdown after the init process exits. This PR handles this and passes the error all the way back to the client, and correctly causes a build step running a container which hits a system error to fail, rather than blindly trying to keep going, assuming all is good, and get a subsequent failure on a commit.
With this change, assuming an error occurs, here's an example of a failure which previous was reported as a commit error:
```
The command 'powershell -Command $ErrorActionPreference = 'Stop'; $ProgressPreference = 'SilentlyContinue'; Install-WindowsFeature -Name Web-App-Dev ; Install-WindowsFeature -Name ADLDS; Install-WindowsFeature -Name Web-Mgmt-Compat; Install-WindowsFeature -Name Web-Mgmt-Service; Install-WindowsFeature -Name Web-Metabase; Install-WindowsFeature -Name Web-Lgcy-Scripting; Install-WindowsFeature -Name Web-WMI; Install-WindowsFeature -Name Web-WHC; Install-WindowsFeature -Name Web-Scripting-Tools; Install-WindowsFeature -Name Web-Net-Ext45; Install-WindowsFeature -Name Web-ASP; Install-WindowsFeature -Name Web-ISAPI-Ext; Install-WindowsFeature -Name Web-ISAPI-Filter; Install-WindowsFeature -Name Web-Default-Doc; Install-WindowsFeature -Name Web-Dir-Browsing; Install-WindowsFeature -Name Web-Http-Errors; Install-WindowsFeature -Name Web-Static-Content; Install-WindowsFeature -Name Web-Http-Redirect; Install-WindowsFeature -Name Web-DAV-Publishing; Install-WindowsFeature -Name Web-Health; Install-WindowsFeature -Name Web-Http-Logging; Install-WindowsFeature -Name Web-Custom-Logging; Install-WindowsFeature -Name Web-Log-Libraries; Install-WindowsFeature -Name Web-Request-Monitor; Install-WindowsFeature -Name Web-Http-Tracing; Install-WindowsFeature -Name Web-Stat-Compression; Install-WindowsFeature -Name Web-Dyn-Compression; Install-WindowsFeature -Name Web-Security; Install-WindowsFeature -Name Web-Windows-Auth; Install-WindowsFeature -Name Web-Basic-Auth; Install-WindowsFeature -Name Web-Url-Auth; Install-WindowsFeature -Name Web-WebSockets; Install-WindowsFeature -Name Web-AppInit; Install-WindowsFeature -Name NET-WCF-HTTP-Activation45; Install-WindowsFeature -Name NET-WCF-Pipe-Activation45; Install-WindowsFeature -Name NET-WCF-TCP-Activation45;' returned a non-zero code: 4294967295: container shutdown failed: container ba9c65054d42d4830fb25ef55e4ab3287550345aa1a2bb265df4e5bfcd79c78a encountered an error during WaitTimeout: failure in a Windows system call: The compute system exited unexpectedly. (0xc0370106)
```
Without this change, it would be incorrectly reported such as in this comment: https://github.com/moby/moby/issues/32838#issuecomment-309621097
```
Step 3/8 : ADD buildtools C:/buildtools
re-exec error: exit status 1: output: time="2017-06-20T11:37:38+10:00" level=error msg="hcsshim::ImportLayer failed in Win32: The system cannot find the path specified. (0x3) layerId=\\\\?\\C:\\ProgramData\\docker\\windowsfilter\\b41d28c95f98368b73fc192cb9205700e21
6691495c1f9ac79b9b04ec4923ea2 flavour=1 folder=C:\\Windows\\TEMP\\hcs232661915"
hcsshim::ImportLayer failed in Win32: The system cannot find the path specified. (0x3) layerId=\\?\C:\ProgramData\docker\windowsfilter\b41d28c95f98368b73fc192cb9205700e216691495c1f9ac79b9b04ec4923ea2 flavour=1 folder=C:\Windows\TEMP\hcs232661915
```
This fixes an issue where the container LogPath was empty when the
non-blocking logging mode was enabled. This change sets the LogPath on
the container as soon as the path is generated, instead of setting the
LogPath on a logger struct and then attempting to pull it off that
logger at a later point. That attempt to pull the LogPath off the logger
was error prone since it assumed that the logger would only ever be a
single type.
Prior to this change docker inspect returned an empty string for
LogPath. This caused issues with tools that rely on docker inspect
output to discover container logs, e.g. Kubernetes.
This commit also removes some LogPath methods that are now unnecessary
and are never invoked.
Signed-off-by: junzhe and mnussbaum <code@getbraintree.com>
On unix, merge secrets/configs handling. This is important because
configs can contain secrets (via templating) and potentially a config
could just simply have secret information "by accident" from the user.
This just make sure that configs are as secure as secrets and de-dups a
lot of code.
Generally this makes everything simpler and configs more secure.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
It's a common scenario for admins and/or monitoring applications to
mount in the daemon root dir into a container. When doing so all mounts
get coppied into the container, often with private references.
This can prevent removal of a container due to the various mounts that
must be configured before a container is started (for example, for
shared /dev/shm, or secrets) being leaked into another namespace,
usually with private references.
This is particularly problematic on older kernels (e.g. RHEL < 7.4)
where a mount may be active in another namespace and attempting to
remove a mountpoint which is active in another namespace fails.
This change moves all container resource mounts into a common directory
so that the directory can be made unbindable.
What this does is prevents sub-mounts of this new directory from leaking
into other namespaces when mounted with `rbind`... which is how all
binds are handled for containers.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
This fix tries to address the issue raised in 35920 where the filter
of `docker ps` with `health=starting` always returns nothing.
The issue was that in container view, the human readable string (`HealthString()` => `Health.String()`)
of health status was used. In case of starting it is `"health: starting"`.
However, the filter still uses `starting` so no match returned.
This fix fixes the issue by using `container.Health.Status()` instead so that it matches
the string (`starting`) passed by filter.
This fix fixes 35920.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
Files that are suffixed with `_linux.go` or `_windows.go` are
already only built on Linux / Windows, so these build-tags
were redundant.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This is a fix to the following issue:
$ docker run --tmpfs /dev/shm busybox sh
docker: Error response from daemon: linux mounts: Duplicate mount point '/dev/shm'.
In current code (daemon.createSpec()), tmpfs mount from --tmpfs is added
to list of mounts (`ms`), when the mount from IpcMounts() is added.
While IpcMounts() is checking for existing mounts first, it does that
by using container.HasMountFor() function which only checks container.Mounts
but not container.Tmpfs.
Ultimately, the solution is to get rid of container.Tmpfs (moving its
data to container.Mounts). Current workaround is to add checking
of container.Tmpfs into container.HasMountFor().
A unit test case is included.
Unfortunately we can't call daemon.createSpec() from a unit test,
as the code relies a lot on various daemon structures to be initialized
properly, and it is hard to achieve. Therefore, we minimally mimick
the code flow of daemon.createSpec() -- barely enough to reproduce
the issue.
https://github.com/moby/moby/issues/35455
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The code in question looks up mounts two times: first by using
HasMountFor(), and then directly by looking in container.MountPoints.
There is no need to do it twice.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Adds a mutex to protect the status, as well. When running the race
detector with the unit test, we can see that the Status field is written
without holding this lock. Adding a mutex to read and set status
addresses the issue.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
While this code was likely called from a single thread before, we have
now seen panics, indicating that it could be called in parallel. This
change adds a mutex to protect opening and closing of the channel. There
may be another root cause associated with this panic, such as something
that led to the calling of this in parallel, as this code is old and we
had seen this condition until recently.
This fix is by no means a permanent fix. Typically, bugs like this
indicate misplaced channel ownership. In idiomatic uses, the channel
should have a particular "owner" that coordinates sending and closure.
In this case, the owner of the channel is unclear, so it gets opened
lazily. Synchronizing this access is a decent solution, but a refactor
may yield better results.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
Currently, if a container removal has failed for some reason,
any client waiting for removal (e.g. `docker run --rm`) is
stuck, waiting for removal to succeed while it has failed already.
For more details and the reproducer, please check
https://github.com/moby/moby/issues/34945
This commit addresses that by allowing `ContainerWait()` with
`container.WaitCondition == "removed"` argument to return an
error in case of removal failure. The `ContainerWaitOKBody`
stucture returned to a client is amended with a pointer to `struct Error`,
containing an error message string, and the `Client.ContainerWait()`
is modified to return the error, if any, to the client.
Note that this feature is only available for API version >= 1.34.
In order for the old clients to be unstuck, we just close the connection
without writing anything -- this causes client's error.
Now, docker-cli would need a separate commit to bump the API to 1.34
and to show an error returned, if any.
[v2: recreate the waitRemove channel after closing]
[v3: document; keep legacy behavior for older clients]
[v4: convert Error from string to pointer to a struct]
[v5: don't emulate old behavior, send empty response in error case]
[v6: rename legacy* vars to include version suffix]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The shutdown timeout for containers in insufficient on Windows. If the daemon is shutting down, and a container takes longer than expected to shut down, this can cause the container to remain in a bad state after restart, and never be able to start again. Increasing the timeout makes this less likely to occur.
Signed-off-by: Darren Stahl <darst@microsoft.com>
Signed-off-by: John Howard <jhoward@microsoft.com>
This PR has the API changes described in https://github.com/moby/moby/issues/34617.
Specifically, it adds an HTTP header "X-Requested-Platform" which is a JSON-encoded
OCI Image-spec `Platform` structure.
In addition, it renames (almost all) uses of a string variable platform (and associated)
methods/functions to os. This makes it much clearer to disambiguate with the swarm
"platform" which is really os/arch. This is a stepping stone to getting the daemon towards
fully multi-platform/arch-aware, and makes it clear when "operating system" is being
referred to rather than "platform" which is misleadingly used - sometimes in the swarm
meaning, but more often as just the operating system.
Take an extra reference to rwlayer while the container is being
committed or exported to avoid the removal of that layer.
Also add some checks before commit/export.
Signed-off-by: Yuanhong Peng <pengyuanhong@huawei.com>
The promise package represents a simple enough concurrency pattern that
replicating it in place is sufficient. To end the propagation of this
package, it has been removed and the uses have been inlined.
While this code could likely be refactored to be simpler without the
package, the changes have been minimized to reduce the possibility of
defects. Someone else may want to do further refactoring to remove
closures and reduce the number of goroutines in use.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
This enables docker cp and ADD/COPY docker build support for LCOW.
Originally, the graphdriver.Get() interface returned a local path
to the container root filesystem. This does not work for LCOW, so
the Get() method now returns an interface that LCOW implements to
support copying to and from the container.
Signed-off-by: Akash Gupta <akagup@microsoft.com>
Use strongly typed errors to set HTTP status codes.
Error interfaces are defined in the api/errors package and errors
returned from controllers are checked against these interfaces.
Errors can be wraeped in a pkg/errors.Causer, as long as somewhere in the
line of causes one of the interfaces is implemented. The special error
interfaces take precedence over Causer, meaning if both Causer and one
of the new error interfaces are implemented, the Causer is not
traversed.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Since the commit d88fe447df ("Add support for sharing /dev/shm/ and
/dev/mqueue between containers") container's /dev/shm is mounted on the
host first, then bind-mounted inside the container. This is done that
way in order to be able to share this container's IPC namespace
(and the /dev/shm mount point) with another container.
Unfortunately, this functionality breaks container checkpoint/restore
(even if IPC is not shared). Since /dev/shm is an external mount, its
contents is not saved by `criu checkpoint`, and so upon restore any
application that tries to access data under /dev/shm is severily
disappointed (which usually results in a fatal crash).
This commit solves the issue by introducing new IPC modes for containers
(in addition to 'host' and 'container:ID'). The new modes are:
- 'shareable': enables sharing this container's IPC with others
(this used to be the implicit default);
- 'private': disables sharing this container's IPC.
In 'private' mode, container's /dev/shm is truly mounted inside the
container, without any bind-mounting from the host, which solves the
issue.
While at it, let's also implement 'none' mode. The motivation, as
eloquently put by Justin Cormack, is:
> I wondered a while back about having a none shm mode, as currently it is
> not possible to have a totally unwriteable container as there is always
> a /dev/shm writeable mount. It is a bit of a niche case (and clearly
> should never be allowed to be daemon default) but it would be trivial to
> add now so maybe we should...
...so here's yet yet another mode:
- 'none': no /dev/shm mount inside the container (though it still
has its own private IPC namespace).
Now, to ultimately solve the abovementioned checkpoint/restore issue, we'd
need to make 'private' the default mode, but unfortunately it breaks the
backward compatibility. So, let's make the default container IPC mode
per-daemon configurable (with the built-in default set to 'shareable'
for now). The default can be changed either via a daemon CLI option
(--default-shm-mode) or a daemon.json configuration file parameter
of the same name.
Note one can only set either 'shareable' or 'private' IPC modes as a
daemon default (i.e. in this context 'host', 'container', or 'none'
do not make much sense).
Some other changes this patch introduces are:
1. A mount for /dev/shm is added to default OCI Linux spec.
2. IpcMode.Valid() is simplified to remove duplicated code that parsed
'container:ID' form. Note the old version used to check that ID does
not contain a semicolon -- this is no longer the case (tests are
modified accordingly). The motivation is we should either do a
proper check for container ID validity, or don't check it at all
(since it is checked in other places anyway). I chose the latter.
3. IpcMode.Container() is modified to not return container ID if the
mode value does not start with "container:", unifying the check to
be the same as in IpcMode.IsContainer().
3. IPC mode unit tests (runconfig/hostconfig_test.go) are modified
to add checks for newly added values.
[v2: addressed review at https://github.com/moby/moby/pull/34087#pullrequestreview-51345997]
[v3: addressed review at https://github.com/moby/moby/pull/34087#pullrequestreview-53902833]
[v4: addressed the case of upgrading from older daemon, in this case
container.HostConfig.IpcMode is unset and this is valid]
[v5: document old and new IpcMode values in api/swagger.yaml]
[v6: add the 'none' mode, changelog entry to docs/api/version-history.md]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Delete needs to release names related to a container even if that
container isn't present in the db. However, slightly overzealous error
checking causes the transaction to get rolled back. Ignore the error
from Delete on the container itself, since it may not be present.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Currently, names are maintained by a separate system called "registrar".
This means there is no way to atomically snapshot the state of
containers and the names associated with them.
We can add this atomicity and simplify the code by storing name
associations in the memdb. This removes the need for pkg/registrar, and
makes snapshots a lot less expensive because they no longer need to copy
all the names. This change also avoids some problematic behavior from
pkg/registrar where it returns slices which may be modified later on.
Note that while this change makes the *snapshotting* atomic, it doesn't
yet do anything to make sure containers are named at the same time that
they are added to the database. We can do that by adding a transactional
interface, either as a followup, or as part of this PR.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Do not change pause state when restoring container's
status, or status in docker will be different with
status in runc.
Signed-off-by: Fengtu Wang <wangfengtu@huawei.com>
Description:
1. start a container with restart=always.
`docker run -d --restart=always ubuntu sleep 3`
2. container init process exits.
3. use `docker pause <id>` to pause this container.
if the pause action is before cgroup data is removed and after the init process died.
`Pause` operation will success to write cgroup data, but actually do not freeze any process.
And then docker received pause event and stateExit event from
containerd, the docker state will be Running(paused), but the container
is free running.
Then we can not remove it, stop it , pause it and unpause it.
Signed-off-by: Wentao Zhang <zhangwentao234@huawei.com>
If a container doesn't exist in the memdb, First will return nil, not an
error. This should be checked for before using the result.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Reuse existing structures and rely on json serialization to deep copy
Container objects.
Also consolidate all "save" operations on container.CheckpointTo, which
now both saves a serialized json to disk, and replicates state to the
ACID in-memory store.
Signed-off-by: Fabio Kung <fabio.kung@gmail.com>
Replicate relevant mutations to the in-memory ACID store. Readers will
then be able to query container state without locking.
Signed-off-by: Fabio Kung <fabio.kung@gmail.com>
The Solaris version (previously daemon/inspect_solaris.go) was
apparently missing some fields that should be available on that
platform.
Signed-off-by: Fabio Kung <fabio.kung@gmail.com>
Doing a chown/chmod automatically can cause `EPERM` in some cases (e.g.
with an NFS mount). Currently Docker will always call chown+chmod on a
volume path unless `:nocopy` is passed in, but we don't need to make
these calls if the perms and ownership already match and potentially
avoid an uneccessary `EPERM`.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
The use of pools.Copy avoids io.Copy's internal buffer allocation.
This commit replaces io.Copy with pools.Copy to avoid the allocation of
buffers in io.Copy.
Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com>
Commit abd72d4008 added
a "FIXME" comment to the container "State", mentioning
that a container cannot be both "Running" and "Paused".
This comment was incorrect, because containers on
Linux actually _must_ be running in order to be
paused.
This patch adds additional information both in a
comment, and in the API documentation to clarify
that these booleans are not mutually exclusive.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The commit adds capability to accept csv parameters
for network option in service create/update commands.The change
includes name,alias driver options specific to the network.
With this the following will be supported
docker service create --name web --network name=docknet,alias=web1,driver-opt=field1=value1 nginx
docker service create --name web --network docknet nginx
docker service update web --network-add name=docknet,alias=web1,driver-opt=field1=value1
docker service update web --network-rm docknet
Signed-off-by: Abhinandan Prativadi <abhi@docker.com>
This patch adds the untilRemoved option to the ContainerWait API which
allows the client to wait until the container is not only exited but
also removed.
This patch also adds some more CLI integration tests for waiting for a
created container and waiting with the new --until-removed flag.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Handle detach sequence in CLI
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Update Container Wait Conditions
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Apply container wait changes to API 1.30
The set of changes to the containerWait API missed the cut for the
Docker 17.05 release (API version 1.29). This patch bumps the version
checks to use 1.30 instead.
This patch also makes a minor update to a testfile which was added to
the builder/dockerfile package.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Remove wait changes from CLI
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Address minor nits on wait changes
- Changed the name of the tty Proxy wrapper to `escapeProxy`
- Removed the unnecessary Error() method on container.State
- Fixes a typo in comment (repeated word)
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Use router.WithCancel in the containerWait handler
This handler previously added this functionality manually but now uses
the existing wrapper which does it for us.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Add WaitCondition constants to api/types/container
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Address more ContainerWait review comments
- Update ContainerWait backend interface to not return pointer values
for container.StateStatus type.
- Updated container state's Wait() method comments to clarify that a
context MUST be used for cancelling the request, setting timeouts,
and to avoid goroutine leaks.
- Removed unnecessary buffering when making channels in the client's
ContainerWait methods.
- Renamed result and error channels in client's ContainerWait methods
to clarify that only a single result or error value would be sent
on the channel.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Move container.WaitCondition type to separate file
... to avoid conflict with swagger-generated code for API response
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Address more ContainerWait review comments
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
This patch consolidates the two WaitStop and WaitWithContext methods
on the container.State type. Now there is a single method, Wait, which
takes a context and a bool specifying whether to wait for not just a
container exit but also removal.
The behavior has been changed slightly so that a wait call during a
Created state will not return immediately but instead wait for the
container to be started and then exited.
The interface has been changed to no longer block, but instead returns
a channel on which the caller can receive a *StateStatus value which
indicates the ExitCode or an error if there was one (like a context
timeout or state transition error).
These changes have been propagated through the rest of the deamon to
preserve all other existing behavior.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)