[lxc-devel] [PATCH 9/9] lxc-device: rewrite lxc-device.

[Serge Hallyn]

Quoting Dongsheng Yang (yangds.fnst at cn.fujitsu.com):
> As there is a function named attach_interface to pass
> a interface to container now, we do not need to relay on
> python impolementation for lxc-device any more.

Don't we still need it for non-network device node?

> Signed-off-by: Dongsheng Yang <yangds.fnst at cn.fujitsu.com>
> ---
>  src/lxc/Makefile.am  |   4 +-
>  src/lxc/lxc-device   |  97 ------------------------------
>  src/lxc/lxc_device.c | 166 +++++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 168 insertions(+), 99 deletions(-)
>  delete mode 100644 src/lxc/lxc-device
>  create mode 100644 src/lxc/lxc_device.c
> 
> diff --git a/src/lxc/Makefile.am b/src/lxc/Makefile.am
> index 8322e62..dab5350 100644
> --- a/src/lxc/Makefile.am
> +++ b/src/lxc/Makefile.am
> @@ -163,14 +163,12 @@ endif
>  bin_SCRIPTS = lxc-checkconfig
>  
>  EXTRA_DIST = \
> -	lxc-device \
>  	lxc-ls \
>  	lxc-top \
>  	lxc.net \
>  	lxc-restore-net
>  
>  if ENABLE_PYTHON
> -bin_SCRIPTS += lxc-device
>  bin_SCRIPTS += lxc-ls
>  bin_SCRIPTS += lxc-start-ephemeral
>  else
> @@ -191,6 +189,7 @@ bin_PROGRAMS = \
>  	lxc-console \
>  	lxc-create \
>  	lxc-destroy \
> +	lxc-device \
>  	lxc-execute \
>  	lxc-freeze \
>  	lxc-info \
> @@ -222,6 +221,7 @@ lxc_cgroup_SOURCES = lxc_cgroup.c
>  lxc_config_SOURCES = lxc_config.c
>  lxc_console_SOURCES = lxc_console.c
>  lxc_destroy_SOURCES = lxc_destroy.c
> +lxc_device_SOURCES = lxc_device.c
>  lxc_execute_SOURCES = lxc_execute.c
>  lxc_freeze_SOURCES = lxc_freeze.c
>  lxc_info_SOURCES = lxc_info.c
> diff --git a/src/lxc/lxc-device b/src/lxc/lxc-device
> deleted file mode 100644
> index dca161e..0000000
> --- a/src/lxc/lxc-device
> +++ /dev/null
> @@ -1,97 +0,0 @@
> -#!/usr/bin/python3
> -#
> -# lxc-device: Add devices to a running container
> -#
> -# This python implementation is based on the work done in the original
> -# shell implementation done by Serge Hallyn in Ubuntu (and other contributors)
> -#
> -# (C) Copyright Canonical Ltd. 2012
> -#
> -# Authors:
> -# Stéphane Graber <stgraber at ubuntu.com>
> -#
> -# This library is free software; you can redistribute it and/or
> -# modify it under the terms of the GNU Lesser General Public
> -# License as published by the Free Software Foundation; either
> -# version 2.1 of the License, or (at your option) any later version.
> -#
> -# This library is distributed in the hope that it will be useful,
> -# but WITHOUT ANY WARRANTY; without even the implied warranty of
> -# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> -# Lesser General Public License for more details.
> -#
> -# You should have received a copy of the GNU Lesser General Public
> -# License along with this library; if not, write to the Free Software
> -# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> -#
> -
> -import argparse
> -import gettext
> -import lxc
> -import os
> -
> -_ = gettext.gettext
> -gettext.textdomain("lxc-device")
> -
> -# Begin parsing the command line
> -parser = argparse.ArgumentParser(description=_("LXC: Manage devices"),
> -                                 formatter_class=argparse.RawTextHelpFormatter)
> -
> -# Global arguments
> -parser.add_argument("-n", dest="container", metavar="CONTAINER",
> -                    help=_("Name of the container to add the device to"),
> -                    required=True)
> -
> -parser.add_argument("-P", "--lxcpath", dest="lxcpath", metavar="PATH",
> -                    help=_("Use specified container path"), default=None)
> -
> -parser.add_argument("--version", action="version", version=lxc.version)
> -
> -# Commands
> -subparsers = parser.add_subparsers()
> -subparser_add = subparsers.add_parser('add', help=_('Add a device'))
> -subparser_add.set_defaults(action="add")
> -
> -subparser_add.add_argument(dest="device", metavar="DEVICE",
> -                           help=_("Add a device "
> -                                  "(path to a node or interface name)"))
> -
> -subparser_add.add_argument(dest="name", metavar="NAME", nargs="?",
> -                           help=_("Use an alternative path or name "
> -                                  "in the container"))
> -
> -args = parser.parse_args()
> -
> -# Some basic checks
> -## Check for valid action
> -if not hasattr(args, "action"):
> -    parser.error(_("You must specify an action."))
> -
> -## Don't rename if no alternative name
> -if not args.name:
> -    args.name = args.device
> -
> -## Check that the container is ready
> -container = lxc.Container(args.container, args.lxcpath)
> -
> -## Check that we have control over the container
> -if not container.controllable:
> -    parser.error("Insufficent privileges to control: %s" % container.name)
> -
> -## Check that the container is running
> -if not container.running:
> -    parser.error("The container must be running.")
> -
> -# Do the work
> -if args.action == "add":
> -    if os.path.exists("/sys/class/net/%s/" % args.device):
> -        ret = container.add_device_net(args.device, args.name)
> -    else:
> -        ret = container.add_device_node(args.device, args.name)
> -
> -    if ret:
> -        print("Added '%s' to '%s' as '%s'." %
> -              (args.device, container.name, args.name))
> -    else:
> -        print("Failed to add '%s' to '%s' as '%s'." %
> -              (args.device, container.name, args.name))
> diff --git a/src/lxc/lxc_device.c b/src/lxc/lxc_device.c
> new file mode 100644
> index 0000000..963f934
> --- /dev/null
> +++ b/src/lxc/lxc_device.c
> @@ -0,0 +1,166 @@
> +/*
> + * lxc: linux Container library
> + *
> + * Authors:
> + * Dongsheng Yang <yangds.fnst at cn.fujitsu.com>
> + *
> + * This library is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * This library is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with this library; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +#include <stdio.h>
> +#include <unistd.h>
> +#include <sys/types.h>
> +#include <libgen.h>
> +#include <string.h>
> +#include <limits.h>
> +
> +#include <lxc/lxccontainer.h>
> +
> +#include "utils.h"
> +#include "lxc.h"
> +#include "log.h"
> +
> +#include "arguments.h"
> +
> +#if HAVE_IFADDRS_H
> +#include <ifaddrs.h>
> +#else
> +#include <../include/ifaddrs.h>
> +#endif
> +
> +lxc_log_define(lxc_device, lxc);
> +
> +static const struct option my_longopts[] = {
> +	LXC_COMMON_OPTIONS
> +};
> +
> +static struct lxc_arguments my_args = {
> +	.progname = "lxc-devicee",
> +	.help     = "\
> +--name=NAME -- COMMAND\n\
> +\n\
> +lxc-device attach or detach device to container.\n\
> +lxc-device -n name add|del ifname.\n\
> +\n\
> +Options :\n\
> +  -n, --name=NAME      NAME for name of the container",
> +	.options  = my_longopts,
> +	.parser   = NULL,
> +	.checker  = NULL,
> +};
> +
> +static bool is_interface(const char* dev_name, pid_t pid)
> +{
> +	pid_t p = fork();
> +
> +	if (p == 0) {
> +		struct ifaddrs *interfaceArray = NULL, *tempIfAddr = NULL;
> +
> +		switch_to_newnet(pid);
> +
> +		/* Grab the list of interfaces */
> +		if (getifaddrs(&interfaceArray)) {
> +			ERROR("failed to get interfaces list");
> +			exit(-1);
> +		}
> +
> +		/* Iterate through the interfaces */
> +		for (tempIfAddr = interfaceArray; tempIfAddr != NULL; tempIfAddr = tempIfAddr->ifa_next) {
> +			if (strcmp(tempIfAddr->ifa_name, dev_name) == 0) {
> +				exit(0);
> +			}
> +		}
> +		exit(1);
> +	}
> +
> +	if (wait_for_pid(p) == 0) {
> +		return true;
> +	}
> +	return false;
> +}
> +
> +int main(int argc, char *argv[])
> +{
> +	struct lxc_container *c;
> +	char *cmd, *dev_name, *dst_name;
> +	int ret = 1;
> +
> +	if (lxc_arguments_parse(&my_args, argc, argv))
> +		goto err;
> +
> +	if (!my_args.log_file)
> +		my_args.log_file = "none";
> +
> +	if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
> +			 my_args.progname, my_args.quiet, my_args.lxcpath[0]))
> +		goto err;
> +	lxc_log_options_no_override();
> +
> +	c = lxc_container_new(my_args.name, my_args.lxcpath[0]);
> +	if (!c) {
> +		ERROR("No such container: %s:%s", my_args.lxcpath[0], my_args.name);
> +		goto err;
> +	}
> +
> +	if (!c->is_running(c)) {
> +		ERROR("Container %s is not running.", c->name);
> +		goto err1;
> +	}
> +
> +	if (my_args.argc < 2) {
> +		ERROR(my_args.help);
> +		goto err1;
> +	}
> +
> +	cmd = my_args.argv[0];
> +	dev_name = my_args.argv[1];
> +	if (my_args.argc < 3)
> +		dst_name = dev_name;
> +	else
> +		dst_name = my_args.argv[2];
> +
> +	if (strcmp(cmd, "add") == 0) {
> +		if (is_interface(dev_name, 1)) {
> +			ret = c->attach_interface(c, dev_name, dst_name);
> +		} else {
> +			ret = c->add_device_node(c, dev_name, dst_name);
> +		}
> +		if (ret != true) {
> +			ERROR("Failed to add %s to %s.", dev_name, c->name);
> +			ret = 1;
> +			goto err1;
> +		}
> +		INFO("Added %s to %s.", dev_name, c->name);
> +	} else if (strcmp(cmd, "del") == 0) {
> +		if (is_interface(dev_name, c->init_pid(c))) {
> +			ret = c->detach_interface(c, dev_name, dst_name);
> +		} else {
> +			ret = c->remove_device_node(c, dev_name, dst_name);
> +		}
> +		if (ret != true) {
> +			ERROR("Failed to del %s from %s.", dev_name, c->name);
> +			ret = 1;
> +			goto err1;
> +		}
> +		INFO("Deled %s from %s.", dev_name, c->name);
> +	} else {
> +		ERROR(my_args.help);
> +		goto err1;
> +	}
> +	exit(0);
> +err1:
> +	lxc_container_put(c);
> +err:
> +	exit(ret);
> +}
> -- 
> 1.8.4.2
>