Improve the dhclient hook for OCI compat

Signed-off-by: Jonathan Calmels <jcalmels@nvidia.com>

Signed-off-by: Jonathan Calmels <jcalmels@nvidia.com>

Excerpt from dnsmasq(8):
By default, the DHCP server will attempt to ensure that an address in not
in use before allocating it to a host. It does this by sending an ICMP echo
request (aka "ping") to the address in question. If it gets a reply, then the
address must already be in use, and another is tried. This flag disables this check.

This is useful if one expects all the containers to get an IP address
from the LXC authoritative DHCP server and wants to speed up the process
of getting a lease.
Signed-off-by: Jonathan Calmels <jcalmels@nvidia.com>

- Merge dhclient-start and dhclient-stop into a single hook.
- Wait for a lease before returning from the hook.
- Generate a logfile when LXC log level is either DEBUG or TRACE.
- Rely on namespace file descriptors for the stop hook.
- Use settings from /<sysconf>/lxc/dhclient.conf if available.
- Attempt to cleanup if dhclient fails to shutdown properly.
Signed-off-by: Jonathan Calmels <jcalmels@nvidia.com>

[monitor] wrong statement of break

hooks: add mount hook to configure access to NVIDIA GPUs

conf.c: small fix for args of mount_entry

Update Japanese lxc.container.conf(5)

and:
* remove empty paragraph in English man
* untabify in Japanese man
Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>

Update for commit 14a7b0f9Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>

Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>

Update for commit 61d7a733Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>

Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>

Signed-off-by: Yifeng Tan <tanyifeng1@huawei.com>

if lxc_abstract_unix_connect fail and return -1,  this code never goto retry.
Signed-off-by: liuhao <liuhao27@huawei.com>

This hook requires the nvidia-container-cli tool provided by libnvidia-container:
https://github.com/nvidia/libnvidia-container

For containers that do not have CUDA_VERSION or NVIDIA_VISIBLE_DEVICES
set in the environment, the hook will be a no-op.

To enable in the configuration file:
lxc.hook.mount = /usr/local/share/lxc/hooks/nvidia
Signed-off-by: Felix Abecassis <fabecassis@nvidia.com>

start: reap intermediate process

When we inherit namespaces we need to reap the attaching process.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

conf.c: add relative option for lxc.mount.entry

Signed-off-by: Yifeng Tan <tanyifeng1@huawei.com>

lxc_init: fix cgroup parsing 

utils: use lxc_raw_clone() in run_command()

coverity: #1426132
coverity: #1426133
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

coverity: #1426131
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

commands: fix race when open()/close() cmd socket

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

This is based on raw_clone in systemd but adapted to our needs. The main reason
is that we need an implementation of fork()/clone() that does guarantee us that
no pthread_atfork() handlers are run. While clone() in glibc currently doesn't
run pthread_atfork() handlers we should be fine but there's no guarantee that
this won't be the case in the future. So let's do the syscall directly - or as
direct as we can. An additional nice feature is that we get fork() behavior,
i.e. lxc_raw_clone() returns 0 in the child and the child pid in the parent.

Our implementation tries to make sure that we cover all cases according to
kernel sources. Note that we are not interested in any arguments that could be
passed after the stack.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

add --share-$NS= support to lxc-execute

dir_detect: warn on eperm

criu: add feature check capability

When we report STOPPED to a caller and then close the command socket it is
technically possible - and I've seen this happen on the test builders - that a
container start() right after a wait() will receive ECONNREFUSED because it
called open() before we close(). So for all new state clients simply close the
command socket. This will inform all state clients that the container is
STOPPED and also prevents a race between a open()/close() on the command socket
causing a new process to get ECONNREFUSED because we haven't yet closed the
command socket.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

This adds a simple test case which verifies that the new migrate() API
command 'MIGRATE_FEATURE_CHECK' works as expected.

If a feature does not exist on the currently running
architecture/kernel/criu combination it does not report an error as this
is a valid scenario.
Signed-off-by: Adrian Reber <areber@redhat.com>

For migration optimization features like pre-copy or post-copy migration
the support cannot be determined by simply looking at the CRIU version.
Features like that depend on the architecture/kernel/criu combination
and CRIU offers a feature checking interface to query if it is
supported.

This adds a LXC interface to query CRIU for those feature via the
migrate() API call. For the recent pre-copy migration support in LXD
this can be used to automatically detect if pre-copy migration should be
used.

In addition to the existing migrate() API commands this adds a new
command: 'MIGRATE_FEATURE_CHECK'.

The migrate_opts{} structure is extended by the member features_to_check
which is a bitmask defining which CRIU features should be queried.

Currently only the querying of the features FEATURE_MEM_TRACK and
FEATURE_LAZY_PAGES is supported.
Signed-off-by: Adrian Reber <areber@redhat.com>

if user has lxc.rootfs.path = /some/path/foo, but can't access
some piece of that path, then we'll get an unhelpful "failed to
mount" without any indication of the problem.

At least show that there is a permission problem.
Signed-off-by: Serge Hallyn <shallyn@cisco.com>

Signed-off-by: Tycho Andersen <tycho@tycho.ws>

confile: add lxc.hook.version

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Unblocks #2013.
Unblocks #2015.
Closes #1766.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>