[lxc-devel] [PATCH] introduce lxcapi_rename for renaming containers

[S.Çağlar Onur]

Hi Serge,

On Mon, Dec 16, 2013 at 9:47 AM, Serge Hallyn <serge.hallyn at ubuntu.com> wrote:
> Quoting S.Çağlar Onur (caglar at 10ur.org):
>> lxcapi_rename implemented as a convenience function as lately
>> I find myself in a need to rename a container due to a
>> typo in its name. I could have started over but didn't want
>> to spend more time (to installing extra packages and changing
>> their configuration) on it.
>>
>> c->clone() followed by c->destroy() did the trick for me and I
>> though it could be helpful to the other people, so here it is.
>>
>> Signed-off-by: S.Çağlar Onur <caglar at 10ur.org>
>
> Looks ok, but should you be specifying LXC_CLONE_COPYHOOKS |
> LXC_CLONE_KEEPMACADDR  as clone flags?

I thought I should to be keeping the container intact as much as I
can, assuming something might be using those values (like
redhat/centos/fedora ifcfg-* files where you could specify HWADDR)

>> ---
>>  src/lxc/lxccontainer.c | 33 +++++++++++++++++++++++++++++++++
>>  src/lxc/lxccontainer.h | 10 ++++++++++
>>  2 files changed, 43 insertions(+)
>>
>> diff --git a/src/lxc/lxccontainer.c b/src/lxc/lxccontainer.c
>> index 6326724..1af8d62 100644
>> --- a/src/lxc/lxccontainer.c
>> +++ b/src/lxc/lxccontainer.c
>> @@ -2596,6 +2596,38 @@ out:
>>       return NULL;
>>  }
>>
>> +static bool lxcapi_rename(struct lxc_container *c, const char *newname)
>> +{
>> +     struct bdev *bdev;
>> +     struct lxc_container *newc;
>> +     int flags = LXC_CLONE_KEEPMACADDR | LXC_CLONE_COPYHOOKS;
>> +
>> +     if (!c || !c->name || !c->config_path)
>> +             return false;
>> +
>> +     bdev = bdev_init(c->lxc_conf->rootfs.path, c->lxc_conf->rootfs.mount, NULL);
>> +     if (!bdev) {
>> +             ERROR("Failed to find original backing store type");
>> +             return false;
>> +     }
>> +
>> +     newc = lxcapi_clone(c, newname, c->config_path, flags, NULL, bdev->type, 0, NULL);
>> +     bdev_put(bdev);
>> +     if (!newc) {
>> +             lxc_container_put(newc);
>> +             return false;
>> +     }
>> +
>> +     if (newc && lxcapi_is_defined(newc))
>> +             lxc_container_put(newc);
>> +
>> +     if (!lxcapi_destroy(c)) {
>> +             ERROR("Could not destroy existing container %s", c->name);
>> +             return false;
>> +     }
>> +     return true;
>> +}
>> +
>>  static int lxcapi_attach(struct lxc_container *c, lxc_attach_exec_t exec_function, void *exec_payload, lxc_attach_options_t *options, pid_t *attached_process)
>>  {
>>       if (!c)
>> @@ -3139,6 +3171,7 @@ struct lxc_container *lxc_container_new(const char *name, const char *configpath
>>       c->wait = lxcapi_wait;
>>       c->set_config_item = lxcapi_set_config_item;
>>       c->destroy = lxcapi_destroy;
>> +     c->rename = lxcapi_rename;
>>       c->save_config = lxcapi_save_config;
>>       c->get_keys = lxcapi_get_keys;
>>       c->create = lxcapi_create;
>> diff --git a/src/lxc/lxccontainer.h b/src/lxc/lxccontainer.h
>> index 3e1b492..b7c5313 100644
>> --- a/src/lxc/lxccontainer.h
>> +++ b/src/lxc/lxccontainer.h
>> @@ -326,6 +326,16 @@ struct lxc_container {
>>                       struct bdev_specs *specs, int flags, ...);
>>
>>       /*!
>> +      * \brief Rename a container
>> +      *
>> +      * \param c Container.
>> +      * \param newname New name to be used for the container.
>> +      *
>> +      * \return \c true on success, else \c false.
>> +      */
>> +     bool (*rename)(struct lxc_container *c, const char *newname);
>> +
>> +     /*!
>>        * \brief Request the container reboot by sending it \c SIGINT.
>>        *
>>        * \param c Container.
>> --
>> 1.8.3.2
>>
>> _______________________________________________
>> lxc-devel mailing list
>> lxc-devel at lists.linuxcontainers.org
>> http://lists.linuxcontainers.org/listinfo/lxc-devel
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-- 
S.Çağlar Onur <caglar at 10ur.org>