Now that the static linux SDK we use has libarchive linked against it,
we can finally live our dream (/s) of supporting copying directories
in/out a little easier. This was.. kind of annoying. I think the very
simple route of writing archive to guest/host -> streaming over grpc is
simplest, but on the guest end we have a couple problems:
1. The VMs rootfs is read only today always, which is a good thing to me
and I don't want to change if we don't have to.
2. Writing the archive to the containers rootfs temporarily could work,
but it's a bit weird, and the user can make the containers rootfs
readonly which would screw that plan.
3. We could write it to /run or /tmp, but they're tmpfs and dealing with
the headache of the user possibly tarring an enormous dir is one I don't
want to care about.
So, that leaves us with the (truthfully better to me) approach of trying
to write the tar data directly to the host and skipping grpc which kinda
forces us to have a temp spot. Because of that, I made it such that we
pass a port number from host<->guest, and transfer the actual data
(either the single file or tarred dir contents) over the vsock port
instead. The stream is kinda clunky, but it just serves as a means to
exchange metadata and a "we're done" signifier.
When we set a gateway outside a subnet in Linux, this fails with:
```
ip-route-add-default: netlink response indicates error, rc = -101
```
To resolve the error, we should first add a route to the gateway outside
the subnet, which this PR does.
It's possible a user doesn't want the full stats list, and only wants
cpu/mem etc. This plumbs through the ability to filter to only what is
requested. This, while we're already here, adds in memory.event output
to the stats list. For that specifically, I think eventually we may want
a streaming variant of this so you can get alerted of changes in the
file immediately instead of polling/one off reads, but this is useful
for now.
Add a streaming rpc to copy single files in and out. This can easily be
extended to support copying directories, but we need the guest agent to
be able to tar/untar, and we'll need to figure out what that model is.
Closes#138
This rounds up cgroup and network stats (via netlink) and exposes them
via an agent rpc and on LinuxContainer. While this is not an entirely
accurate view into the full resources being used by the container given
the virtualized nature (doesn't account for vcpu, device etc overhead)
it should give an accurate overview of the workload resource usage in
the guest.
This change besides the stated goal also removes the interfaceStatistics
rpc and just moves these network stats into the new containerStatistics
one. Related to that, it also renames the InterfaceStatistics struct to
NetworkStatistics and moves this into ContainerStatistics as a nested
struct.
Adds support for grabbing stats for an iface. This will be surfaced in a
coming change to get container level statistics from the guest, where
one field will be network stats.
Have wait return a struct containing the exit code and the time at which
the process actually exited. This is useful so higher level tools (like
container) don't need to craft a date themselves, and it will be more
accurate as it's taken in the guest directly after the process exits.
This change adds in a new rpc that we probably should swap to for the
underlying implementation of a couple rpcs we currently have. This new
rpc simply writes to an existing or new file some data. This is useful
for guest (and container) setup for things like /etc/hosts,
/etc/resolv.conf, writing to one-off cgroup files and so on.
Currently I've just implemented subtree_control toggling for the root cg
in standardSetup with this new change, but in the future I'd like to
swap the implementations of our /etc/hosts and /etc/resolv.conf logic
with this.
Closes#206
Much like we have support for supplying DNS configurations and writing
out /etc/resolv.conf, this adds a way to write out /etc/hosts for a
given container.
This allows the user the ability to raise an EOF for the containers
stdin. Today there's no way to close stdin so something as simple as
"cat" and relying on EOF to move the process forward doesn't work
