src/lxc/lxc_checkpoint.c

   1 /*
   2  * lxc: linux Container library
   3  *
   4  * (C) Copyright IBM Corp. 2007, 2010
   5  *
   6  * Authors:
   7  * Daniel Lezcano <dlezcano at fr.ibm.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23 #define _GNU_SOURCE
  24 #include <assert.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28 #include <errno.h>
  29 #include <sys/stat.h>
  30 #include <sys/types.h>
  31 #include <fcntl.h>
  32
  33 #include <lxc/lxc.h>
  34 #include <lxc/log.h>
  35 #include <lxc/utils.h>
  36
  37 #include "arguments.h"
  38 #include "config.h"
  39
  40 lxc_log_define(lxc_checkpoint_ui, lxc_checkpoint);
  41
  42 static int my_checker(const struct lxc_arguments* args)
  43 {
  44         if ((!args->statefile) && (args->statefd == -1)) {
  45                 lxc_error(args, "no statefile specified");
  46                 return -1;
  47         }
  48
  49         if ((args->statefile) && (args->statefd != -1)) {
  50                 lxc_error(args, "--statefile AND --statefd abnormally set");
  51                 return -1;
  52         }
  53
  54         return 0;
  55 }
  56
  57 static int my_parser(struct lxc_arguments* args, int c, char* arg)
  58 {
  59         switch (c) {
  60         case 'k': args->flags = LXC_FLAG_HALT; break;
  61         case 'p': args->flags = LXC_FLAG_PAUSE; break;
  62         case 'S': args->statefile = arg; break;
  63         case 'd': {
  64                         int fd;
  65                         fd = lxc_arguments_str_to_int(args, arg);
  66                         if (fd < 0)
  67                                 return -1;
  68
  69                         args->statefd = fd;
  70                         break;
  71                 }
  72         }
  73         return 0;
  74 }
  75
  76 static const struct option my_longopts[] = {
  77         {"kill", no_argument, 0, 'k'},
  78         {"pause", no_argument, 0, 'p'},
  79         {"statefile", required_argument, 0, 'S'},
  80         {"statefd", required_argument, 0, 'd'},
  81         LXC_COMMON_OPTIONS
  82 };
  83
  84 static struct lxc_arguments my_args = {
  85         .progname = "lxc-checkpoint",
  86         .help     = "\
  87 --name=NAME --statefile FILE\n\
  88 \n\
  89 lxc-checkpoint checkpoints in FILE the NAME container\n\
  90 \n\
  91 Options :\n\
  92   -n, --name=NAME      NAME for name of the container\n\
  93   -k, --kill           stop the container after checkpoint\n\
  94   -p, --pause          don't unfreeze the container after the checkpoint\n\
  95   -S, --statefile=FILE write the container state into this file, or\n\
  96   -d, --statefd=FD write the container state into this file descriptor\n",
  97
  98         .options  = my_longopts,
  99         .parser   = my_parser,
 100         .checker  = my_checker,
 101
 102         .statefd  = -1,
 103 };
 104
 105 int main(int argc, char *argv[])
 106 {
 107         int ret;
 108         int sfd = -1;
 109
 110         ret = lxc_arguments_parse(&my_args, argc, argv);
 111         if (ret)
 112                 return ret;
 113
 114         ret = lxc_log_init(my_args.log_file, my_args.log_priority,
 115                            my_args.progname, my_args.quiet);
 116         if (ret)
 117                 return ret;
 118
 119         if (my_args.statefd != -1)
 120                 sfd = my_args.statefd;
 121
 122 #define OPEN_WRITE_MODE O_CREAT | O_RDWR | O_EXCL | O_CLOEXEC | O_LARGEFILE
 123         if (my_args.statefile) {
 124                 sfd = open(my_args.statefile, OPEN_WRITE_MODE, 0600);
 125                 if (sfd < 0) {
 126                         ERROR("'%s' open failure : %m", my_args.statefile);
 127                         return sfd;
 128                 }
 129         }
 130
 131         ret = lxc_checkpoint(my_args.name, sfd, my_args.flags);
 132
 133         assert(ret == 0 || ret == -1);
 134
 135         if (ret)
 136                 ERROR("failed to checkpoint '%s'", my_args.name);
 137         else
 138                 INFO("'%s' checkpointed", my_args.name);
 139
 140         if (my_args.statefile)
 141                 close(sfd);
 142         return ret;
 143 }