ref: #1464
This tries to solve issues with races around process state. First it
adds the process mutex around the state call so that any state changes,
deletions, etc will be handled in order.
Second, for IsNoExist errors from the runtime, return a stopped state if
a process has been removed from the underlying OCI runtime but not from
the shim yet. This shouldn't happen with the lock from above but its
hare to verify this issue.
Third, handle shim disconnections and return an ErrNotFound.
Forth, don't abort returning all tasks if one task is unable to return
its state.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This changes Wait() from returning an error whenever you call wait on a
stopped process/task to returning the exit status from the process.
This also adds the exit status to the Status() call on a process/task so
that a user can Wait(), check status, then cancel the wait to avoid
races in event handling.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This splits up the create and start of an exec process in the shim to
have two separate steps like the initial process. This will allow
better state reporting for individual process along with a more robust
wait for execs.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Since we now have a common set of error definitions, mapped to existing
error codes, we no longer need the specialized error codes used for
interaction with linux processes. The main issue was that string
matching was being used to map these to useful error codes. With this
change, we use errors defined in the `errdefs` package, which map
cleanly to GRPC error codes and are recoverable on either side of the
request.
The main focus of this PR was in removin these from the shim. We may
need follow ups to ensure error codes are preserved by the `Tasks`
service.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
These rpcs only return pids []uint32 so should be named that way in
order to have other rpcs that list Processes such as Exec'd processes.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This moves the shim's API and protos out of the containerd services
package and into the linux runtime package. This is because the shim is
an implementation detail of the linux runtime that we have and it is not
a containerd user facing api.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
We need a separate API for handing the exit status and deletion of
Exec'd processes to make sure they are properly cleaned up within the
shim and daemon.
Fixes#973
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This allows attach of existing fifos to be done without any information
stored on the client side.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Working from feedback on the existing implementation, we have now
introduced a central metadata object to represent the lifecycle and pin
the resources required to implement what people today know as
containers. This includes the runtime specification and the root
filesystem snapshots. We also allow arbitrary labeling of the container.
Such provisions will bring the containerd definition of container closer
to what is expected by users.
The objects that encompass today's ContainerService, centered around the
runtime, will be known as tasks. These tasks take on the existing
lifecycle behavior of containerd's containers, which means that they are
deleted when they exit. Largely, there are no other changes except for
naming.
The `Container` object will operate purely as a metadata object. No
runtime state will be held on `Container`. It only informs the execution
service on what is required for creating tasks and the resources in use
by that container. The resources referenced by that container will be
deleted when the container is deleted, if not in use. In this sense,
users can create, list, label and delete containers in a similar way as
they do with docker today, without the complexity of runtime locks that
plagues current implementations.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
