destroy: implement in the api

[mirror_lxc.git] / src / lxc / lxccontainer.c

/* liblxcapi
 *
 * Copyright © 2012 Serge Hallyn <serge.hallyn@ubuntu.com>.
 * Copyright © 2012 Canonical Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2, as
 * published by the Free Software Foundation.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _GNU_SOURCE
#include <pthread.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <sched.h>
#include "config.h"
#include "lxc.h"
#include "state.h"
#include "lxccontainer.h"
#include "conf.h"
#include "confile.h"
#include "cgroup.h"
#include "commands.h"
#include "version.h"
#include "log.h"
#include "bdev.h"
#include "utils.h"
#include <lxc/utils.h>
#include <lxc/monitor.h>
#include <sched.h>
#include <fcntl.h>
#include <arpa/inet.h>
#include <ifaddrs.h>

lxc_log_define(lxc_container, lxc);

static bool file_exists(char *f)
{
        struct stat statbuf;

        return stat(f, &statbuf) == 0;
}

/*
 * A few functions to help detect when a container creation failed.
 * If a container creation was killed partway through, then trying
 * to actually start that container could harm the host.  We detect
 * this by creating a 'partial' file under the container directory,
 * and keeping an advisory lock.  When container creation completes,
 * we remove that file.  When we load or try to start a container, if
 * we find that file, without a flock, we remove the container.
 */
int ongoing_create(struct lxc_container *c)
{
        int len = strlen(c->config_path) + strlen(c->name) + 10;
        char *path = alloca(len);
        int fd, ret;
        ret = snprintf(path, len, "%s/%s/partial", c->config_path, c->name);
        if (ret < 0 || ret >= len) {
                ERROR("Error writing partial pathname");
                return -1;
        }

        if (!file_exists(path))
                return 0;
        if (process_lock())
                return -1;
        if ((fd = open(path, O_RDWR)) < 0) {
                // give benefit of the doubt
                SYSERROR("Error opening partial file");
                process_unlock();
                return 0;
        }
        if ((ret = flock(fd, LOCK_EX | LOCK_NB)) == -1 &&
                        errno == EWOULDBLOCK) {
                // create is still ongoing
                close(fd);
                process_unlock();
                return 1;
        }
        // create completed but partial is still there.
        close(fd);
        process_unlock();
        return 2;
}

int create_partial(struct lxc_container *c)
{
        // $lxcpath + '/' + $name + '/partial' + \0
        int len = strlen(c->config_path) + strlen(c->name) + 10;
        char *path = alloca(len);
        int fd, ret;
        ret = snprintf(path, len, "%s/%s/partial", c->config_path, c->name);
        if (ret < 0 || ret >= len) {
                ERROR("Error writing partial pathname");
                return -1;
        }
        if (process_lock() < 0)
                return -1;
        if ((fd=open(path, O_CREAT | O_EXCL, 0755)) < 0) {
                SYSERROR("Erorr creating partial file");
                process_unlock();
                return -1;
        }
        if (flock(fd, LOCK_EX) < 0) {
                SYSERROR("Error locking partial file %s", path);
                close(fd);
                process_unlock();
                return -1;
        }
        process_unlock();

        return fd;
}

void remove_partial(struct lxc_container *c, int fd)
{
        // $lxcpath + '/' + $name + '/partial' + \0
        int len = strlen(c->config_path) + strlen(c->name) + 10;
        char *path = alloca(len);
        int ret;

        close(fd);
        ret = snprintf(path, len, "%s/%s/partial", c->config_path, c->name);
        if (ret < 0 || ret >= len) {
                ERROR("Error writing partial pathname");
                return;
        }
        if (process_lock())
                return;
        if (unlink(path) < 0)
                SYSERROR("Error unlink partial file %s", path);
        process_unlock();
}

/* LOCKING
 * 1. c->privlock protects the struct lxc_container from multiple threads.
 * 2. c->slock protects the on-disk container data
 * 3. thread_mutex protects process data (ex: fd table) from multiple threads
 * slock is an flock, which does not exclude threads.  Therefore slock should
 * always be wrapped inside privlock.
 * NOTHING mutexes two independent programs with their own struct
 * lxc_container for the same c->name, between API calls.  For instance,
 * c->config_read(); c->start();  Between those calls, data on disk
 * could change (which shouldn't bother the caller unless for instance
 * the rootfs get moved).  c->config_read(); update; c->config_write();
 * Two such updaters could race.  The callers should therefore check their
 * results.  Trying to prevent that would necessarily expose us to deadlocks
 * due to hung callers.  So I prefer to keep the locks only within our own
 * functions, not across functions.
 *
 * If you're going to fork while holding a lxccontainer, increment
 * c->numthreads (under privlock) before forking.  When deleting,
 * decrement numthreads under privlock, then if it hits 0 you can delete.
 * Do not ever use a lxccontainer whose numthreads you did not bump.
 */

static void lxc_container_free(struct lxc_container *c)
{
        if (!c)
                return;

        if (c->configfile) {
                free(c->configfile);
                c->configfile = NULL;
        }
        if (c->error_string) {
                free(c->error_string);
                c->error_string = NULL;
        }
        if (c->slock) {
                lxc_putlock(c->slock);
                c->slock = NULL;
        }
        if (c->privlock) {
                lxc_putlock(c->privlock);
                c->privlock = NULL;
        }
        if (c->name) {
                free(c->name);
                c->name = NULL;
        }
        if (c->lxc_conf) {
                lxc_conf_free(c->lxc_conf);
                c->lxc_conf = NULL;
        }
        if (c->config_path) {
                free(c->config_path);
                c->config_path = NULL;
        }
        free(c);
}

/*
 * Consider the following case:
freer                         |    racing get()er
==================================================================
lxc_container_put()           |   lxc_container_get()
\ lxclock(c->privlock)        |   c->numthreads < 1? (no)
\ c->numthreads = 0           |   \ lxclock(c->privlock) -> waits
\ lxcunlock()                 |   \
\ lxc_container_free()        |   \ lxclock() returns
                              |   \ c->numthreads < 1 -> return 0
\ \ (free stuff)              |
\ \ sem_destroy(privlock)     |

 * When the get()er checks numthreads the first time, one of the following
 * is true:
 * 1. freer has set numthreads = 0.  get() returns 0
 * 2. freer is between lxclock and setting numthreads to 0.  get()er will
 *    sem_wait on privlock, get lxclock after freer() drops it, then see
 *    numthreads is 0 and exit without touching lxclock again..
 * 3. freer has not yet locked privlock.  If get()er runs first, then put()er
 *    will see --numthreads = 1 and not call lxc_container_free().
*/

int lxc_container_get(struct lxc_container *c)
{
        if (!c)
                return 0;

        // if someone else has already started freeing the container, don't
        // try to take the lock, which may be invalid
        if (c->numthreads < 1)
                return 0;

        if (container_mem_lock(c))
                return 0;
        if (c->numthreads < 1) {
                // bail without trying to unlock, bc the privlock is now probably
                // in freed memory
                return 0;
        }
        c->numthreads++;
        container_mem_unlock(c);
        return 1;
}

int lxc_container_put(struct lxc_container *c)
{
        if (!c)
                return -1;
        if (container_mem_lock(c))
                return -1;
        if (--c->numthreads < 1) {
                container_mem_unlock(c);
                lxc_container_free(c);
                return 1;
        }
        container_mem_unlock(c);
        return 0;
}

static bool lxcapi_is_defined(struct lxc_container *c)
{
        struct stat statbuf;
        bool ret = false;
        int statret;

        if (!c)
                return false;

        if (container_mem_lock(c))
                return false;
        if (!c->configfile)
                goto out;
        statret = stat(c->configfile, &statbuf);
        if (statret != 0)
                goto out;
        ret = true;

out:
        container_mem_unlock(c);
        return ret;
}

static const char *lxcapi_state(struct lxc_container *c)
{
        const char *ret;
        lxc_state_t s;

        if (!c)
                return NULL;
        if (container_disk_lock(c))
                return NULL;
        s = lxc_getstate(c->name, c->config_path);
        ret = lxc_state2str(s);
        container_disk_unlock(c);

        return ret;
}

static bool is_stopped_locked(struct lxc_container *c)
{
        lxc_state_t s;
        s = lxc_getstate(c->name, c->config_path);
        return (s == STOPPED);
}

static bool lxcapi_is_running(struct lxc_container *c)
{
        const char *s;

        if (!c)
                return false;
        s = lxcapi_state(c);
        if (!s || strcmp(s, "STOPPED") == 0)
                return false;
        return true;
}

static bool lxcapi_freeze(struct lxc_container *c)
{
        int ret;
        if (!c)
                return false;

        if (container_disk_lock(c))
                return false;
        ret = lxc_freeze(c->name, c->config_path);
        container_disk_unlock(c);
        if (ret)
                return false;
        return true;
}

static bool lxcapi_unfreeze(struct lxc_container *c)
{
        int ret;
        if (!c)
                return false;

        if (container_disk_lock(c))
                return false;
        ret = lxc_unfreeze(c->name, c->config_path);
        container_disk_unlock(c);
        if (ret)
                return false;
        return true;
}

static pid_t lxcapi_init_pid(struct lxc_container *c)
{
        if (!c)
                return -1;

        return lxc_cmd_get_init_pid(c->name, c->config_path);
}

static bool load_config_locked(struct lxc_container *c, const char *fname)
{
        if (!c->lxc_conf)
                c->lxc_conf = lxc_conf_init();
        if (c->lxc_conf && !lxc_config_read(fname, c->lxc_conf))
                return true;
        return false;
}

static bool lxcapi_load_config(struct lxc_container *c, const char *alt_file)
{
        bool ret = false;
        const char *fname;
        if (!c)
                return false;

        fname = c->configfile;
        if (alt_file)
                fname = alt_file;
        if (!fname)
                return false;
        if (container_disk_lock(c))
                return false;
        ret = load_config_locked(c, fname);
        container_disk_unlock(c);
        return ret;
}

static void lxcapi_want_daemonize(struct lxc_container *c)
{
        if (!c)
                return;
        c->daemonize = 1;
}

static bool lxcapi_wait(struct lxc_container *c, const char *state, int timeout)
{
        int ret;

        if (!c)
                return false;

        ret = lxc_wait(c->name, state, timeout, c->config_path);
        return ret == 0;
}


static bool wait_on_daemonized_start(struct lxc_container *c)
{
        /* we'll probably want to make this timeout configurable? */
        int timeout = 5, ret, status;

        /*
         * our child is going to fork again, then exit.  reap the
         * child
         */
        ret = wait(&status);
        if (ret == -1 || !WIFEXITED(status) || WEXITSTATUS(status) != 0)
                DEBUG("failed waiting for first dual-fork child");
        return lxcapi_wait(c, "RUNNING", timeout);
}

/*
 * I can't decide if it'd be more convenient for callers if we accept '...',
 * or a null-terminated array (i.e. execl vs execv)
 */
static bool lxcapi_start(struct lxc_container *c, int useinit, char * const argv[])
{
        int ret;
        struct lxc_conf *conf;
        int daemonize = 0;
        char *default_args[] = {
                "/sbin/init",
                '\0',
        };

        /* container exists */
        if (!c)
                return false;
        /* container has been setup */
        if (!c->lxc_conf)
                return false;

        if ((ret = ongoing_create(c)) < 0) {
                ERROR("Error checking for incomplete creation");
                return false;
        }
        if (ret == 2) {
                ERROR("Error: %s creation was not completed", c->name);
                c->destroy(c);
                return false;
        } else if (ret == 1) {
                ERROR("Error: creation of %s is ongoing", c->name);
                return false;
        }

        /* is this app meant to be run through lxcinit, as in lxc-execute? */
        if (useinit && !argv)
                return false;

        if (container_mem_lock(c))
                return false;
        conf = c->lxc_conf;
        daemonize = c->daemonize;
        container_mem_unlock(c);

        if (useinit) {
                ret = lxc_execute(c->name, argv, 1, conf, c->config_path);
                return ret == 0 ? true : false;
        }

        if (!argv)
                argv = default_args;

        /*
        * say, I'm not sure - what locks do we want here?  Any?
        * Is liblxc's locking enough here to protect the on disk
        * container?  We don't want to exclude things like lxc_info
        * while container is running...
        */
        if (daemonize) {
                if (!lxc_container_get(c))
                        return false;
                lxc_monitord_spawn(c->config_path);

                if (process_lock())
                        return false;
                pid_t pid = fork();
                if (pid < 0) {
                        lxc_container_put(c);
                        process_unlock();
                        return false;
                }
                if (pid != 0) {
                        ret = wait_on_daemonized_start(c);
                        process_unlock();
                        return ret;
                }
                process_unlock();
                /* second fork to be reparented by init */
                pid = fork();
                if (pid < 0) {
                        SYSERROR("Error doing dual-fork");
                        return false;
                }
                if (pid != 0)
                        exit(0);
                /* like daemon(), chdir to / and redirect 0,1,2 to /dev/null */
                if (chdir("/")) {
                        SYSERROR("Error chdir()ing to /.");
                        return false;
                }
                close(0);
                close(1);
                close(2);
                open("/dev/null", O_RDONLY);
                open("/dev/null", O_RDWR);
                open("/dev/null", O_RDWR);
                setsid();
        }

reboot:
        conf->reboot = 0;
        ret = lxc_start(c->name, argv, conf, c->config_path);

        if (conf->reboot) {
                INFO("container requested reboot");
                conf->reboot = 0;
                goto reboot;
        }

        if (daemonize) {
                lxc_container_put(c);
                exit (ret == 0 ? true : false);
        } else {
                return (ret == 0 ? true : false);
        }
}

/*
 * note there MUST be an ending NULL
 */
static bool lxcapi_startl(struct lxc_container *c, int useinit, ...)
{
        va_list ap;
        char **inargs = NULL, **temp;
        int n_inargs = 0;
        bool bret = false;

        /* container exists */
        if (!c)
                return false;

        /* build array of arguments if any */
        va_start(ap, useinit);
        while (1) {
                char *arg;
                arg = va_arg(ap, char *);
                if (!arg)
                        break;
                n_inargs++;
                temp = realloc(inargs, n_inargs * sizeof(*inargs));
                if (!temp) {
                        va_end(ap);
                        goto out;
                }
                inargs = temp;
                inargs[n_inargs - 1] = strdup(arg);  // not sure if it's safe not to copy
        }
        va_end(ap);

        /* add trailing NULL */
        if (n_inargs) {
                n_inargs++;
                temp = realloc(inargs, n_inargs * sizeof(*inargs));
                if (!temp)
                        goto out;
                inargs = temp;
                inargs[n_inargs - 1] = NULL;
        }

        bret = lxcapi_start(c, useinit, inargs);

out:
        if (inargs) {
                int i;
                for (i = 0; i < n_inargs; i++) {
                        if (inargs[i])
                                free(inargs[i]);
                }
                free(inargs);
        }

        return bret;
}

static bool lxcapi_stop(struct lxc_container *c)
{
        int ret;

        if (!c)
                return false;

        ret = lxc_cmd_stop(c->name, c->config_path);

        return ret == 0;
}

static bool valid_template(char *t)
{
        struct stat statbuf;
        int statret;

        statret = stat(t, &statbuf);
        if (statret == 0)
                return true;
        return false;
}

/*
 * create the standard expected container dir
 */
static bool create_container_dir(struct lxc_container *c)
{
        char *s;
        int len, ret;

        len = strlen(c->config_path) + strlen(c->name) + 2;
        s = malloc(len);
        if (!s)
                return false;
        ret = snprintf(s, len, "%s/%s", c->config_path, c->name);
        if (ret < 0 || ret >= len) {
                free(s);
                return false;
        }
        ret = mkdir(s, 0755);
        if (ret) {
                if (errno == EEXIST)
                        ret = 0;
                else
                        SYSERROR("failed to create container path for %s\n", c->name);
        }
        free(s);
        return ret == 0;
}

/*
 * backing stores not (yet) supported
 * for ->create, argv contains the arguments to pass to the template,
 * terminated by NULL.  If no arguments, you can just pass NULL.
 */
static bool lxcapi_create(struct lxc_container *c, const char *t, char *const argv[])
{
        bool bret = false;
        pid_t pid;
        char *tpath = NULL, **newargv;
        int partial_fd, ret, len, nargs = 0;

        if (!c)
                return false;

        len = strlen(LXCTEMPLATEDIR) + strlen(t) + strlen("/lxc-") + 1;
        tpath = malloc(len);
        if (!tpath)
                return false;
        ret = snprintf(tpath, len, "%s/lxc-%s", LXCTEMPLATEDIR, t);
        if (ret < 0 || ret >= len)
                goto out;
        if (!valid_template(tpath)) {
                ERROR("bad template: %s\n", t);
                goto out;
        }

        if (!c->save_config(c, NULL)) {
                ERROR("failed to save starting configuration for %s\n", c->name);
                goto out;
        }

        /* container is already created if we have a config and rootfs.path is accessible */
        if (lxcapi_is_defined(c) && c->lxc_conf && c->lxc_conf->rootfs.path && access(c->lxc_conf->rootfs.path, F_OK) == 0)
                goto out;

        /* Mark that this container is being created */
        if ((partial_fd = create_partial(c)) < 0)
                goto out;

        /* we're going to fork.  but since we'll wait for our child, we
         * don't need to lxc_container_get */

        if (container_disk_lock(c))
                goto out;

        pid = fork();
        if (pid < 0) {
                SYSERROR("failed to fork task for container creation template\n");
                goto out_unlock;
        }

        if (pid == 0) { // child
                char *patharg, *namearg;
                int i;

                close(0);
                close(1);
                close(2);
                open("/dev/null", O_RDONLY);
                open("/dev/null", O_RDWR);
                open("/dev/null", O_RDWR);

                /*
                 * create our new array, pre-pend the template name and
                 * base args
                 */
                if (argv)
                        for (; argv[nargs]; nargs++) ;
                nargs += 3;  // template, path and name args
                newargv = malloc(nargs * sizeof(*newargv));
                if (!newargv)
                        exit(1);
                newargv[0] = (char *)t;

                len = strlen(c->config_path) + strlen(c->name) + strlen("--path=") + 2;
                patharg = malloc(len);
                if (!patharg)
                        exit(1);
                ret = snprintf(patharg, len, "--path=%s/%s", c->config_path, c->name);
                if (ret < 0 || ret >= len)
                        exit(1);
                newargv[1] = patharg;
                len = strlen("--name=") + strlen(c->name) + 1;
                namearg = malloc(len);
                if (!namearg)
                        exit(1);
                ret = snprintf(namearg, len, "--name=%s", c->name);
                if (ret < 0 || ret >= len)
                        exit(1);
                newargv[2] = namearg;

                /* add passed-in args */
                if (argv)
                        for (i = 3; i < nargs; i++)
                                newargv[i] = argv[i-3];

                /* add trailing NULL */
                nargs++;
                newargv = realloc(newargv, nargs * sizeof(*newargv));
                if (!newargv)
                        exit(1);
                newargv[nargs - 1] = NULL;

                /* execute */
                execv(tpath, newargv);
                SYSERROR("failed to execute template %s", tpath);
                exit(1);
        }

        if (wait_for_pid(pid) != 0) {
                ERROR("container creation template for %s failed\n", c->name);
                goto out_unlock;
        }

        // now clear out the lxc_conf we have, reload from the created
        // container
        if (c->lxc_conf)
                lxc_conf_free(c->lxc_conf);
        c->lxc_conf = NULL;
        bret = load_config_locked(c, c->configfile);

out_unlock:
        if (partial_fd >= 0)
                remove_partial(c, partial_fd);
        container_disk_unlock(c);
out:
        if (tpath)
                free(tpath);
        return bret;
}

static bool lxcapi_reboot(struct lxc_container *c)
{
        pid_t pid;

        if (!c)
                return false;
        if (!c->is_running(c))
                return false;
        pid = c->init_pid(c);
        if (pid <= 0)
                return false;
        if (kill(pid, SIGINT) < 0)
                return false;
        return true;

}

static bool lxcapi_shutdown(struct lxc_container *c, int timeout)
{
        bool retv;
        pid_t pid;

        if (!c)
                return false;

        if (!timeout)
                timeout = -1;
        if (!c->is_running(c))
                return true;
        pid = c->init_pid(c);
        if (pid <= 0)
                return true;
        kill(pid, SIGPWR);
        retv = c->wait(c, "STOPPED", timeout);
        if (!retv && timeout > 0) {
                c->stop(c);
                retv = c->wait(c, "STOPPED", 0); // 0 means don't wait
        }
        return retv;
}

static bool lxcapi_createl(struct lxc_container *c, const char *t, ...)
{
        bool bret = false;
        char **args = NULL, **temp;
        va_list ap;
        int nargs = 0;

        if (!c)
                return false;

        /*
         * since we're going to wait for create to finish, I don't think we
         * need to get a copy of the arguments.
         */
        va_start(ap, t);
        while (1) {
                char *arg;
                arg = va_arg(ap, char *);
                if (!arg)
                        break;
                nargs++;
                temp = realloc(args, (nargs+1) * sizeof(*args));
                if (!temp) {
                        va_end(ap);
                        goto out;
                }
                args = temp;
                args[nargs - 1] = arg;
        }
        va_end(ap);
        if (args)
                args[nargs] = NULL;

        bret = c->create(c, t, args);

out:
        if (args)
                free(args);
        return bret;
}

static bool lxcapi_clear_config_item(struct lxc_container *c, const char *key)
{
        int ret;

        if (!c || !c->lxc_conf)
                return false;
        if (container_mem_lock(c))
                return false;
        ret = lxc_clear_config_item(c->lxc_conf, key);
        container_mem_unlock(c);
        return ret == 0;
}

char** lxcapi_get_ips(struct lxc_container *c, char* interface, char* family, int scope)
{
        int count = 0;
        struct ifaddrs *interfaceArray = NULL, *tempIfAddr = NULL;
        char addressOutputBuffer[INET6_ADDRSTRLEN];
        void *tempAddrPtr = NULL;
        char **addresses = NULL, **temp;
        char *address = NULL;
        char new_netns_path[MAXPATHLEN];
        int old_netns = -1, new_netns = -1, ret = 0;

        if (!c->is_running(c))
                goto out;

        /* Save reference to old netns */
        old_netns = open("/proc/self/ns/net", O_RDONLY);
        if (old_netns < 0) {
                SYSERROR("failed to open /proc/self/ns/net");
                goto out;
        }

        /* Switch to new netns */
        ret = snprintf(new_netns_path, MAXPATHLEN, "/proc/%d/ns/net", c->init_pid(c));
        if (ret < 0 || ret >= MAXPATHLEN)
                goto out;

        new_netns = open(new_netns_path, O_RDONLY);
        if (new_netns < 0) {
                SYSERROR("failed to open %s", new_netns_path);
                goto out;
        }

        if (setns(new_netns, CLONE_NEWNET)) {
                SYSERROR("failed to setns");
                goto out;
        }

        /* Grab the list of interfaces */
        if (getifaddrs(&interfaceArray)) {
                SYSERROR("failed to get interfaces list");
                goto out;
        }

        /* Iterate through the interfaces */
        for (tempIfAddr = interfaceArray; tempIfAddr != NULL; tempIfAddr = tempIfAddr->ifa_next) {
                if(tempIfAddr->ifa_addr->sa_family == AF_INET) {
                        if (family && strcmp(family, "inet"))
                                continue;
                        tempAddrPtr = &((struct sockaddr_in *)tempIfAddr->ifa_addr)->sin_addr;
                }
                else {
                        if (family && strcmp(family, "inet6"))
                                continue;

                        if (((struct sockaddr_in6 *)tempIfAddr->ifa_addr)->sin6_scope_id != scope)
                                continue;

                        tempAddrPtr = &((struct sockaddr_in6 *)tempIfAddr->ifa_addr)->sin6_addr;
                }

                if (interface && strcmp(interface, tempIfAddr->ifa_name))
                        continue;
                else if (!interface && strcmp("lo", tempIfAddr->ifa_name) == 0)
                        continue;

                address = (char *)inet_ntop(tempIfAddr->ifa_addr->sa_family,
                                           tempAddrPtr,
                                           addressOutputBuffer,
                                           sizeof(addressOutputBuffer));
                if (!address)
                        continue;

                count += 1;
                temp = realloc(addresses, count * sizeof(*addresses));
                if (!temp) {
                        count--;
                        goto out;
                }
                addresses = temp;
                addresses[count - 1] = strdup(address);
        }

out:
        if(interfaceArray)
                freeifaddrs(interfaceArray);

        /* Switch back to original netns */
        if (old_netns >= 0 && setns(old_netns, CLONE_NEWNET))
                SYSERROR("failed to setns");
        if (new_netns >= 0)
                close(new_netns);
        if (old_netns >= 0)
                close(old_netns);

        /* Append NULL to the array */
        if (count) {
                count++;
                temp = realloc(addresses, count * sizeof(*addresses));
                if (!temp) {
                        int i;
                        for (i = 0; i < count-1; i++)
                                free(addresses[i]);
                        free(addresses);
                        return NULL;
                }
                addresses = temp;
                addresses[count - 1] = NULL;
        }

        return addresses;
}

static int lxcapi_get_config_item(struct lxc_container *c, const char *key, char *retv, int inlen)
{
        int ret;

        if (!c || !c->lxc_conf)
                return -1;
        if (container_mem_lock(c))
                return -1;
        ret = lxc_get_config_item(c->lxc_conf, key, retv, inlen);
        container_mem_unlock(c);
        return ret;
}

static int lxcapi_get_keys(struct lxc_container *c, const char *key, char *retv, int inlen)
{
        if (!key)
                return lxc_listconfigs(retv, inlen);
        /*
         * Support 'lxc.network.<idx>', i.e. 'lxc.network.0'
         * This is an intelligent result to show which keys are valid given
         * the type of nic it is
         */
        if (!c || !c->lxc_conf)
                return -1;
        if (container_mem_lock(c))
                return -1;
        int ret = -1;
        if (strncmp(key, "lxc.network.", 12) == 0)
                ret =  lxc_list_nicconfigs(c->lxc_conf, key, retv, inlen);
        container_mem_unlock(c);
        return ret;
}


/* default config file - should probably come through autoconf */
#define LXC_DEFAULT_CONFIG "/etc/lxc/default.conf"
static bool lxcapi_save_config(struct lxc_container *c, const char *alt_file)
{
        if (!alt_file)
                alt_file = c->configfile;
        if (!alt_file)
                return false;  // should we write to stdout if no file is specified?
        if (!c->lxc_conf)
                if (!c->load_config(c, LXC_DEFAULT_CONFIG)) {
                        ERROR("Error loading default configuration file %s while saving %s\n", LXC_DEFAULT_CONFIG, c->name);
                        return false;
                }

        if (!create_container_dir(c))
                return false;

        FILE *fout = fopen(alt_file, "w");
        if (!fout)
                return false;
        if (container_mem_lock(c)) {
                fclose(fout);
                return false;
        }
        write_config(fout, c->lxc_conf);
        fclose(fout);
        container_mem_unlock(c);
        return true;
}

static const char *lxcapi_get_config_path(struct lxc_container *c);
// do we want the api to support --force, or leave that to the caller?
static bool lxcapi_destroy(struct lxc_container *c)
{
        struct bdev *r;
        bool ret = false;

        /* container is already destroyed if we don't have a config and rootfs.path is not accessible */
        if (!c || !lxcapi_is_defined(c) || !c->lxc_conf || !c->lxc_conf->rootfs.path)
                return false;

        if (lxclock(c->privlock, 0))
                return false;
        if (lxclock(c->slock, 0)) {
                lxcunlock(c->privlock);
                return false;
        }

        if (!is_stopped_locked(c)) {
                // we should queue some sort of error - in c->error_string?
                ERROR("container %s is not stopped", c->name);
                goto out;
        }

        r = bdev_init(c->lxc_conf->rootfs.path, c->lxc_conf->rootfs.mount, NULL);
        if (r) {
                if (r->ops->destroy(r) < 0) {
                        ERROR("Error destroying rootfs for %s", c->name);
                        goto out;
                }
        }

        const char *p1 = lxcapi_get_config_path(c);
        char *path = alloca(strlen(p1) + strlen(c->name) + 2);
        sprintf(path, "%s/%s", p1, c->name);
        if (lxc_rmdir_onedev(path) < 0) {
                ERROR("Error destroying container directory for %s", c->name);
                goto out;
        }
        ret = true;

out:
        lxcunlock(c->privlock);
        lxcunlock(c->slock);
        return ret;
}

static bool lxcapi_set_config_item(struct lxc_container *c, const char *key, const char *v)
{
        int ret;
        bool b = false;
        struct lxc_config_t *config;

        if (!c)
                return false;

        if (container_mem_lock(c))
                return false;

        if (!c->lxc_conf)
                c->lxc_conf = lxc_conf_init();
        if (!c->lxc_conf)
                goto err;
        config = lxc_getconfig(key);
        if (!config)
                goto err;
        ret = config->cb(key, v, c->lxc_conf);
        if (!ret)
                b = true;

err:
        container_mem_unlock(c);
        return b;
}

static char *lxcapi_config_file_name(struct lxc_container *c)
{
        if (!c || !c->configfile)
                return NULL;
        return strdup(c->configfile);
}

static const char *lxcapi_get_config_path(struct lxc_container *c)
{
        if (!c || !c->config_path)
                return NULL;
        return (const char *)(c->config_path);
}

/*
 * not for export
 * Just recalculate the c->configfile based on the
 * c->config_path, which must be set.
 * The lxc_container must be locked or not yet public.
 */
static bool set_config_filename(struct lxc_container *c)
{
        char *newpath;
        int len, ret;

        if (!c->config_path)
                return false;

        /* $lxc_path + "/" + c->name + "/" + "config" + '\0' */
        len = strlen(c->config_path) + strlen(c->name) + strlen("config") + 3;
        newpath = malloc(len);
        if (!newpath)
                return false;

        ret = snprintf(newpath, len, "%s/%s/config", c->config_path, c->name);
        if (ret < 0 || ret >= len) {
                fprintf(stderr, "Error printing out config file name\n");
                free(newpath);
                return false;
        }

        if (c->configfile)
                free(c->configfile);
        c->configfile = newpath;

        return true;
}

static bool lxcapi_set_config_path(struct lxc_container *c, const char *path)
{
        char *p;
        bool b = false;
        char *oldpath = NULL;

        if (!c)
                return b;

        if (container_mem_lock(c))
                return b;

        p = strdup(path);
        if (!p) {
                ERROR("Out of memory setting new lxc path");
                goto err;
        }

        b = true;
        if (c->config_path)
                oldpath = c->config_path;
        c->config_path = p;

        /* Since we've changed the config path, we have to change the
         * config file name too */
        if (!set_config_filename(c)) {
                ERROR("Out of memory setting new config filename");
                b = false;
                free(c->config_path);
                c->config_path = oldpath;
                oldpath = NULL;
        }
err:
        if (oldpath)
                free(oldpath);
        container_mem_unlock(c);
        return b;
}


static bool lxcapi_set_cgroup_item(struct lxc_container *c, const char *subsys, const char *value)
{
        int ret;
        bool b = false;

        if (!c)
                return false;

        if (container_mem_lock(c))
                return false;

        if (is_stopped_locked(c))
                goto err;

        ret = lxc_cgroup_set(c->name, subsys, value, c->config_path);
        if (!ret)
                b = true;
err:
        container_mem_unlock(c);
        return b;
}

static int lxcapi_get_cgroup_item(struct lxc_container *c, const char *subsys, char *retv, int inlen)
{
        int ret = -1;

        if (!c || !c->lxc_conf)
                return -1;

        if (container_mem_lock(c))
                return -1;

        if (is_stopped_locked(c))
                goto out;

        ret = lxc_cgroup_get(c->name, subsys, retv, inlen, c->config_path);

out:
        container_mem_unlock(c);
        return ret;
}

const char *lxc_get_default_config_path(void)
{
        return default_lxc_path();
}

const char *lxc_get_default_lvm_vg(void)
{
        return default_lvm_vg();
}

const char *lxc_get_default_zfs_root(void)
{
        return default_zfs_root();
}

const char *lxc_get_version(void)
{
        return lxc_version();
}

static int copy_file(char *old, char *new)
{
        int in, out;
        ssize_t len, ret;
        char buf[8096];
        struct stat sbuf;

        if (file_exists(new)) {
                ERROR("copy destination %s exists", new);
                return -1;
        }
        ret = stat(old, &sbuf);
        if (ret < 0) {
                SYSERROR("stat'ing %s", old);
                return -1;
        }

        in = open(old, O_RDONLY);
        if (in < 0) {
                SYSERROR("opening original file %s", old);
                return -1;
        }
        out = open(new, O_CREAT | O_EXCL | O_WRONLY, 0644);
        if (out < 0) {
                SYSERROR("opening new file %s", new);
                close(in);
                return -1;
        }

        while (1) {
                len = read(in, buf, 8096);
                if (len < 0) {
                        SYSERROR("reading old file %s", old);
                        goto err;
                }
                if (len == 0)
                        break;
                ret = write(out, buf, len);
                if (ret < len) {  // should we retry?
                        SYSERROR("write to new file %s was interrupted", new);
                        goto err;
                }
        }
        close(in);
        close(out);

        // we set mode, but not owner/group
        ret = chmod(new, sbuf.st_mode);
        if (ret) {
                SYSERROR("setting mode on %s", new);
                return -1;
        }

        return 0;

err:
        close(in);
        close(out);
        return -1;
}

/*
 * we're being passed result of two strstrs(x, y).  We want to write
 * all data up to the first found string, or to end of the string if
 * neither string was found.
 * This function will return the earliest found string if any, or else
 * NULL
 */
static const char *lowest_nonnull(const char *p1, const char *p2)
{
        if (!p1)
                return p2;
        if (!p2)
                return p1;
        return p1 < p2 ? p1 : p2;
}

static int is_word_sep(char c)
{
        switch(c) {
        case '\0':
        case '\n':
        case '\r':
        case '\t':
        case ' ':
        case '=':
        case '/':
                return 1;
        default: return 0;
        }
}

static const char *find_first_wholeword(const char *p, const char *word)
{
        if (!p)
                return NULL;

        while ((p = strstr(p, word)) != NULL) {
                if (is_word_sep(*(p-1)) && is_word_sep(p[strlen(word)]))
                        return p;
                p++;
        }
        return NULL;
}

static int update_name_and_paths(const char *path, struct lxc_container *oldc,
                const char *newname, const char *newpath)
{
        FILE *f;
        long flen;
        char *contents;
        const char *p0, *p1, *p2, *end;
        const char *oldpath = oldc->get_config_path(oldc);
        const char *oldname = oldc->name;

        f = fopen(path, "r");
        if (!f) {
                SYSERROR("opening old config");
                return -1;
        }
        if (fseek(f, 0, SEEK_END) < 0) {
                SYSERROR("seeking to end of old config");
                fclose(f);
                return -1;
        }
        flen = ftell(f);
        if (flen < 0) {
                fclose(f);
                SYSERROR("telling size of old config");
                return -1;
        }
        if (fseek(f, 0, SEEK_SET) < 0) {
                fclose(f);
                SYSERROR("rewinding old config");
                return -1;
        }
        contents = malloc(flen+1);
        if (!contents) {
                SYSERROR("out of memory");
                fclose(f);
                return -1;
        }
        if (fread(contents, 1, flen, f) != flen) {
                free(contents);
                fclose(f);
                SYSERROR("reading old config");
                return -1;
        }
        contents[flen] = '\0';
        if (fclose(f) < 0) {
                free(contents);
                SYSERROR("closing old config");
                return -1;
        }

        f = fopen(path, "w");
        if (!f) {
                SYSERROR("reopening config");
                free(contents);
                return -1;
        }

        p0 = contents;
        end = contents + flen;
        while (1) {
                p1 = find_first_wholeword(p0, oldpath);
                p2 = find_first_wholeword(p0, oldname);
                if (!p1 && !p2) {
                        // write the rest and be done
                        if (fwrite(p0, 1, (end-p0), f) != (end-p0)) {
                                SYSERROR("writing new config");
                                free(contents);
                                fclose(f);
                                return -1;
                        }
                        free(contents);
                        fclose(f);
                        // success
                        return 0;
                } else {
                        const char *p = lowest_nonnull(p1, p2);
                        const char *new = (p == p2) ? newname : newpath;
                        if (fwrite(p0, 1, (p-p0), f) != (p-p0)) {
                                SYSERROR("writing new config");
                                free(contents);
                                fclose(f);
                                return -1;
                        }
                        p0 = p;
                        // now write the newpath or newname
                        if (fwrite(new, 1, strlen(new), f) != strlen(new)) {
                                SYSERROR("writing new name or path in new config");
                                free(contents);
                                fclose(f);
                                return -1;
                        }
                        p0 += (p == p2) ? strlen(oldname) : strlen(oldpath);
                }
        }
}

static int copyhooks(struct lxc_container *oldc, struct lxc_container *c)
{
        int i;
        int ret;
        struct lxc_list *it;

        for (i=0; i<NUM_LXC_HOOKS; i++) {
                lxc_list_for_each(it, &c->lxc_conf->hooks[i]) {
                        char *hookname = it->elem;
                        char *fname = rindex(hookname, '/');
                        char tmppath[MAXPATHLEN];
                        if (!fname) // relative path - we don't support, but maybe we should
                                return 0;
                        // copy the script, and change the entry in confile
                        ret = snprintf(tmppath, MAXPATHLEN, "%s/%s/%s",
                                        c->config_path, c->name, fname+1);
                        if (ret < 0 || ret >= MAXPATHLEN)
                                return -1;
                        ret = copy_file(it->elem, tmppath);
                        if (ret < 0)
                                return -1;
                        free(it->elem);
                        it->elem = strdup(tmppath);
                        if (!it->elem) {
                                ERROR("out of memory copying hook path");
                                return -1;
                        }
                        update_name_and_paths(it->elem, oldc, c->name, c->get_config_path(c));
                }
        }

        c->save_config(c, NULL);
        return 0;
}

static void new_hwaddr(char *hwaddr)
{
        FILE *f = fopen("/dev/urandom", "r");
        if (f) {
                unsigned int seed;
                int ret = fread(&seed, sizeof(seed), 1, f);
                if (ret != 1)
                        seed = time(NULL);
                fclose(f);
                srand(seed);
        } else
                srand(time(NULL));
        snprintf(hwaddr, 18, "00:16:3e:%02x:%02x:%02x",
                        rand() % 255, rand() % 255, rand() % 255);
}

static void network_new_hwaddrs(struct lxc_container *c)
{
        struct lxc_list *it;

        lxc_list_for_each(it, &c->lxc_conf->network) {
                struct lxc_netdev *n = it->elem;
                if (n->hwaddr)
                        new_hwaddr(n->hwaddr);
        }
}

static int copy_fstab(struct lxc_container *oldc, struct lxc_container *c)
{
        char newpath[MAXPATHLEN];
        char *oldpath = oldc->lxc_conf->fstab;
        int ret;

        if (!oldpath)
                return 0;

        char *p = rindex(oldpath, '/');
        if (!p)
                return -1;
        ret = snprintf(newpath, MAXPATHLEN, "%s/%s%s",
                        c->config_path, c->name, p);
        if (ret < 0 || ret >= MAXPATHLEN) {
                ERROR("error printing new path for %s", oldpath);
                return -1;
        }
        if (file_exists(newpath)) {
                ERROR("error: fstab file %s exists", newpath);
                return -1;
        }

        if (copy_file(oldpath, newpath) < 0) {
                ERROR("error: copying %s to %s", oldpath, newpath);
                return -1;
        }
        free(c->lxc_conf->fstab);
        c->lxc_conf->fstab = strdup(newpath);
        if (!c->lxc_conf->fstab) {
                ERROR("error: allocating pathname");
                return -1;
        }

        return 0;
}

static int copy_storage(struct lxc_container *c0, struct lxc_container *c,
                const char *newtype, int flags, const char *bdevdata, unsigned long newsize)
{
        struct bdev *bdev;

        bdev = bdev_copy(c0->lxc_conf->rootfs.path, c0->name, c->name,
                        c0->config_path, c->config_path, newtype, !!(flags & LXC_CLONE_SNAPSHOT),
                        bdevdata, newsize);
        if (!bdev) {
                ERROR("error copying storage");
                return -1;
        }
        free(c->lxc_conf->rootfs.path);
        c->lxc_conf->rootfs.path = strdup(bdev->src);
        bdev_put(bdev);
        if (!c->lxc_conf->rootfs.path)
                return -1;
        // here we could also update all lxc.mount.entries or even
        // items in the lxc.mount fstab list.  As discussed on m-l,
        // we could do either any source paths starting with the
        // lxcpath/oldname, or simply anythign which is not a virtual
        // fs or a bind mount.
        return 0;
}

static int clone_update_rootfs(struct lxc_container *c, int flags, char **hookargs)
{
        int ret = -1;
        char path[MAXPATHLEN];
        struct bdev *bdev;
        FILE *fout;
        pid_t pid;
        struct lxc_conf *conf = c->lxc_conf;

        /* update hostname in rootfs */
        /* we're going to mount, so run in a clean namespace to simplify cleanup */

        pid = fork();
        if (pid < 0)
                return -1;
        if (pid > 0)
                return wait_for_pid(pid);

        if (unshare(CLONE_NEWNS) < 0) {
                ERROR("error unsharing mounts");
                exit(1);
        }
        bdev = bdev_init(c->lxc_conf->rootfs.path, c->lxc_conf->rootfs.mount, NULL);
        if (!bdev)
                exit(1);
        if (bdev->ops->mount(bdev) < 0)
                exit(1);

        if (!lxc_list_empty(&conf->hooks[LXCHOOK_CLONE])) {
                /* Start of environment variable setup for hooks */
                if (setenv("LXC_NAME", c->name, 1)) {
                        SYSERROR("failed to set environment variable for container name");
                }
                if (setenv("LXC_CONFIG_FILE", conf->rcfile, 1)) {
                        SYSERROR("failed to set environment variable for config path");
                }
                if (setenv("LXC_ROOTFS_MOUNT", conf->rootfs.mount, 1)) {
                        SYSERROR("failed to set environment variable for rootfs mount");
                }
                if (setenv("LXC_ROOTFS_PATH", conf->rootfs.path, 1)) {
                        SYSERROR("failed to set environment variable for rootfs mount");
                }

                if (run_lxc_hooks(c->name, "clone", conf, hookargs)) {
                        ERROR("Error executing clone hook for %s", c->name);
                        exit(1);
                }
        }

        if (!(flags & LXC_CLONE_KEEPNAME)) {
                ret = snprintf(path, MAXPATHLEN, "%s/etc/hostname", bdev->dest);
                if (ret < 0 || ret >= MAXPATHLEN)
                        exit(1);
                if (!(fout = fopen(path, "w"))) {
                        SYSERROR("unable to open %s: ignoring\n", path);
                        exit(0);
                }
                if (fprintf(fout, "%s", c->name) < 0)
                        exit(1);
                if (fclose(fout) < 0)
                        exit(1);
        }
        exit(0);
}

/*
 * We want to support:
sudo lxc-clone -o o1 -n n1 -s -L|-fssize fssize -v|--vgname vgname \
        -p|--lvprefix lvprefix -t|--fstype fstype  -B backingstore

-s [ implies overlayfs]
-s -B overlayfs
-s -B aufs

only rootfs gets converted (copied/snapshotted) on clone.
*/

static int create_file_dirname(char *path)
{
        char *p = rindex(path, '/');
        int ret;

        if (!p)
                return -1;
        *p = '\0';
        ret = mkdir(path, 0755);
        if (ret && errno != EEXIST)
                SYSERROR("creating container path %s\n", path);
        *p = '/';
        return ret;
}

struct lxc_container *lxcapi_clone(struct lxc_container *c, const char *newname,
                const char *lxcpath, int flags,
                const char *bdevtype, const char *bdevdata, unsigned long newsize,
                char **hookargs)
{
        struct lxc_container *c2 = NULL;
        char newpath[MAXPATHLEN];
        int ret;
        const char *n, *l;
        FILE *fout;

        if (!c || !c->is_defined(c))
                return NULL;

        if (container_mem_lock(c))
                return NULL;

        if (c->is_running(c)) {
                ERROR("error: Original container (%s) is running", c->name);
                goto out;
        }

        // Make sure the container doesn't yet exist.
        n = newname ? newname : c->name;
        l = lxcpath ? lxcpath : c->get_config_path(c);
        ret = snprintf(newpath, MAXPATHLEN, "%s/%s/config", l, n);
        if (ret < 0  || ret >= MAXPATHLEN) {
                SYSERROR("clone: failed making config pathname");
                goto out;
        }
        if (file_exists(newpath)) {
                ERROR("error: clone: %s exists", newpath);
                goto out;
        }

        if (create_file_dirname(newpath) < 0) {
                ERROR("Error creating container dir for %s", newpath);
                goto out;
        }

        // copy the configuration, tweak it as needed,
        fout = fopen(newpath, "w");
        if (!fout) {
                SYSERROR("open %s", newpath);
                goto out;
        }
        write_config(fout, c->lxc_conf);
        fclose(fout);

        if (update_name_and_paths(newpath, c, n, l) < 0) {
                ERROR("Error updating name in cloned config");
                goto out;
        }

        sprintf(newpath, "%s/%s/rootfs", l, n);
        if (mkdir(newpath, 0755) < 0) {
                SYSERROR("error creating %s", newpath);
                goto out;
        }

        c2 = lxc_container_new(n, l);
        if (!c2) {
                ERROR("clone: failed to create new container (%s %s)", n, l);
                goto out;
        }

        // copy hooks if requested
        if (flags & LXC_CLONE_COPYHOOKS) {
                ret = copyhooks(c, c2);
                if (ret < 0) {
                        ERROR("error copying hooks");
                        goto out;
                }
        }

        if (copy_fstab(c, c2) < 0) {
                ERROR("error copying fstab");
                goto out;
        }

        // update macaddrs
        if (!(flags & LXC_CLONE_KEEPMACADDR))
                network_new_hwaddrs(c2);

        // copy/snapshot rootfs's
        ret = copy_storage(c, c2, bdevtype, flags, bdevdata, newsize);
        if (ret < 0)
                goto out;

        if (!c2->save_config(c2, NULL))
                goto out;

        if (clone_update_rootfs(c2, flags, hookargs) < 0)
                goto out;

        // TODO: update c's lxc.snapshot = count
        container_mem_unlock(c);
        return c2;

out:
        container_mem_unlock(c);
        if (c2) {
                c2->destroy(c2);
                lxc_container_put(c2);
        }

        return NULL;
}

struct lxc_container *lxc_container_new(const char *name, const char *configpath)
{
        struct lxc_container *c;

        c = malloc(sizeof(*c));
        if (!c) {
                fprintf(stderr, "failed to malloc lxc_container\n");
                return NULL;
        }
        memset(c, 0, sizeof(*c));

        if (configpath)
                c->config_path = strdup(configpath);
        else
                c->config_path = strdup(default_lxc_path());

        if (!c->config_path) {
                fprintf(stderr, "Out of memory");
                goto err;
        }

        c->name = malloc(strlen(name)+1);
        if (!c->name) {
                fprintf(stderr, "Error allocating lxc_container name\n");
                goto err;
        }
        strcpy(c->name, name);

        c->numthreads = 1;
        if (!(c->slock = lxc_newlock(c->config_path, name))) {
                fprintf(stderr, "failed to create lock\n");
                goto err;
        }

        if (!(c->privlock = lxc_newlock(NULL, NULL))) {
                fprintf(stderr, "failed to alloc privlock\n");
                goto err;
        }

        if (!set_config_filename(c)) {
                fprintf(stderr, "Error allocating config file pathname\n");
                goto err;
        }

        if (file_exists(c->configfile))
                lxcapi_load_config(c, NULL);

        if (ongoing_create(c) == 2) {
                ERROR("Error: %s creation was not completed", c->name);
                c->destroy(c);
                goto err;
        }

        // assign the member functions
        c->is_defined = lxcapi_is_defined;
        c->state = lxcapi_state;
        c->is_running = lxcapi_is_running;
        c->freeze = lxcapi_freeze;
        c->unfreeze = lxcapi_unfreeze;
        c->init_pid = lxcapi_init_pid;
        c->load_config = lxcapi_load_config;
        c->want_daemonize = lxcapi_want_daemonize;
        c->start = lxcapi_start;
        c->startl = lxcapi_startl;
        c->stop = lxcapi_stop;
        c->config_file_name = lxcapi_config_file_name;
        c->wait = lxcapi_wait;
        c->set_config_item = lxcapi_set_config_item;
        c->destroy = lxcapi_destroy;
        c->save_config = lxcapi_save_config;
        c->get_keys = lxcapi_get_keys;
        c->create = lxcapi_create;
        c->createl = lxcapi_createl;
        c->shutdown = lxcapi_shutdown;
        c->reboot = lxcapi_reboot;
        c->clear_config_item = lxcapi_clear_config_item;
        c->get_config_item = lxcapi_get_config_item;
        c->get_cgroup_item = lxcapi_get_cgroup_item;
        c->set_cgroup_item = lxcapi_set_cgroup_item;
        c->get_config_path = lxcapi_get_config_path;
        c->set_config_path = lxcapi_set_config_path;
        c->clone = lxcapi_clone;
        c->get_ips = lxcapi_get_ips;

        /* we'll allow the caller to update these later */
        if (lxc_log_init(NULL, "none", NULL, "lxc_container", 0, c->config_path)) {
                fprintf(stderr, "failed to open log\n");
                goto err;
        }

        return c;

err:
        lxc_container_free(c);
        return NULL;
}

int lxc_get_wait_states(const char **states)
{
        int i;

        if (states)
                for (i=0; i<MAX_STATE; i++)
                        states[i] = lxc_state2str(i);
        return MAX_STATE;
}