This requires us to check that at cgfsng_ops_init, rather than
cgfs_init.  Cache the hierarchy and cgroup.use info globally
rather than putting it into the per-container info, as cgmanager
does.  This is ok as both cgroup.use and the list of usable
hierarchies are in fact global to a lxc run.

Closes #952
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

Clean exit when read() == -1 && errno != EINTR or read() == 0.
Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

Using EPOLLHUP to determine when to exit the loop is unreliable. Let's exit
clean when read() returns -1 && errno != EINTR or 0.
Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

lxc-attach allocated a pty in a manner that relied on ts->stdinfd and
ts->stdoutfd to be set. We had to resort to a trick to get it working when
output is redirected. The new implementation gets rid of the black magic and
also simplifies the code.

This commit also implements pty logging for lxc-attach. Users will now be able
to log commands and corresponding output to a file given that lxc-attach
allocates a pty.
Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

lxc_console_create() calls lxc_console_peer_default() which in turn calls
lxc_console_sigwinch_init() which sets up the lxc_tty_state struct for the
current pty. Prior to this commit lxc_console_sigwinch_init() would consider
failures to install a SIGWINCH handler fatal and and return NULL. This commit
makes failures to install a SIGWINCH handler non-fatal. In such cases the
lxc_tty_state struct will still be set up but the sigfd member, which contains
the fd which receives SIGWINCH events, will be set to -1. (This also entails
that the sigset_t oldmaks field is meaningless.) Callers of
lxc_console_sigwinch_init() and lxc_console_sigwinch_fini() should thus make
sure that sigfd >= 0 or sigfd != -1 before trying to register a SIGWINCH handler
in e.g. an lxc_mainloop or resetting the sigmask (cf. lxc_attach.c).

These changes also imply that lxc_console_sigwinch_init() only fails with
ENOMEM. Thus, all cases where lxc_console_sigwinch_init() returns NULL are to be
considered fatal. This wasn't the case before this commit.
Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

lxc_mount_auto_mounts(): free memory on failure

lxc-create: bugfixes and small improvements

Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

netlink_open: close socket on error

All uses of netlink_open() assume that on error the
nl_handler doesn't need to be closed, but some error cases
happen after the socket was opened successfully and used to
simply return -errno.
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

- call lxc_container_put() before we exit()
- reorder includes
- use EXIT_FAILURE and EXIT_SUCCESS macros
Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

add more error handling + cleanup copy_storage()

Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

set lxc.rootfs.backend on container creation

Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

Since specifying lxc.rootfs.backend can lead to performance improvements we
always set it during container creation.

This also fixes a bug. do_bdev_create() tried to be smart and retrieve the lower
directory when bdev->type == overlayfs or aufs thereby cutting the path.
However, this operation is done in ovl_mount() and aufs_mount() and both
functions need the full src path for this. The bug didn't show before because
when creating a overlayfs container with e.g.:

	lxc-create -n c -t busybox -B overlayfs

still left bdev->type set to dir and so the code for retrieving the lower dir in
do_bdev_create() was skipped. But by setting lxc.rootfs.backend on container
creation we force bdev->type to be set to e.g. overlayfs and the code gets
executed thereby exposing the bug.
Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

use correct "overlayfs" instead of "ovl"

Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

doc: Add lxc.rootfs.backend in Japanese lxc.container.conf(5)

Update for commit f9039861Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>

Add a document of lxc.rootfs.backend in Korean manpage

Update for commit f9039861Signed-off-by: Sungbae Yoo <sungbae.yoo@samsung.com>

fix spelling mistakes spotted by Debian's lintian

Signed-off-by: Evgeni Golov <evgeni@debian.org>

fix btrfs_recursive_destroy

Signed-off-by: Oleg Freedholm <overlayfs@gmail.com>

switch user facing name to lxc.rootfs.backend

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

rootfs.bdev_type: implement get and clear

clear is just set(x, ""), but before this patch that didn't work bc
"" is nota valid bdev type.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

use more accurate bdev_type name for rootfs.bdev

It'll make future code reading easier.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

2016 04 02/bdev

If that is specified, then we only use the specified backing store type.

This can be useful if you know that lxc.rootfs is a directory type and
you do not want lxc to waste time searching for zfs, btrfs, etc.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

A change in kernel 4.2 caused btrfs_recursive_destroy to
fail to delete unprivileged containers.  This patch restores
the pre-kernel-4.2 behaviour.  Ref: Issue 935.
Signed-off-by: Oleg Freedhom <overlayfs@gmail.com>

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

c/r: support for the criu pageserver