zdtm: Make kernel version check more POSIX-like

Arrays and "&&" in test are not supported by Busybox v1.19.4. The
`set` command can put field-separated arguments into the positional
parameters, which is relatively equivalent to using an array.

Signed-off-by: Christopher Covington <cov@codeaurora.org>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
zdtm: Introduce per-test hooks

This is inspired by two problems we have with cgroup* tests.

1. Tests cannot easily clean after themselves -- one cannot
   remove a cg dir with tasks in it and the root task of
   a test is in a cgroup it tries to remove.

2. After dump old cgroup dirs are remained after the test,
   while criu should restore them (this is what we write
   tests for).

The proposal is to introduce per-test hooks, for now two of
them: --pre-restore and --clean. For cgroup tests both hooks
will remove the created directories.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
cg: Strip trailing \n from property's value

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
cg: Check for name= prefix in controller, not cgset

This should be symmetrical with cg dirs creation.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
cg: A helper for getting controller's yard dir name (and opts)

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
cg: Get yard fd on demand

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
cg: Don't copy path when restoring properties

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
scripts: set CRIU_IMAGE_DIR when running scripts

When doing a restore for LXC, we store some other metadata (which bridge a veth
was on) in the image directory so that the restore script can correctly unlock
a network device and attach it to the right interface. This patch is needed so
that the script can find this metadata.

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Bug-fix in size calculation

Fixes a bug in how PARASITE_MAX_GROUPS was calculated, and adds a
compiler check to assert that parasite_dump_creds doesn't exceed
the page size.

Signed-off-by: Sophie Blee-Goldman <ableegoldman@google.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
test: bers -- Add short help output

Reported-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>