src/lxc/start.h

   1 /*
   2  * lxc: linux Container library
   3  *
   4  * (C) Copyright IBM Corp. 2007, 2008
   5  *
   6  * Authors:
   7  * Daniel Lezcano <daniel.lezcano at free.fr>
   8  * Serge Hallyn <serge@hallyn.com>
   9  * Christian Brauner <christian.brauner@ubuntu.com>
  10  *
  11  * This library is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU Lesser General Public
  13  * License as published by the Free Software Foundation; either
  14  * version 2.1 of the License, or (at your option) any later version.
  15  *
  16  * This library is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public
  22  * License along with this library; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  24  */
  25 #ifndef __LXC_START_H
  26 #define __LXC_START_H
  27
  28 #include <signal.h>
  29 #include <stdbool.h>
  30 #include <sys/param.h>
  31 #include <sys/socket.h>
  32 #include <sys/un.h>
  33
  34 #include "conf.h"
  35 #include "config.h"
  36 #include "namespace.h"
  37 #include "state.h"
  38
  39 struct lxc_handler {
  40         /* The clone flags that were requested. */
  41         int clone_flags;
  42
  43         /* The clone flags to actually use when calling lxc_clone(). They may
  44          * differ from clone_flags because of ordering requirements (e.g.
  45          * CLONE_NEWNET and CLONE_NEWUSER).
  46          */
  47         int on_clone_flags;
  48
  49         /* File descriptor to pin the rootfs for privileged containers. */
  50         int pinfd;
  51
  52         /* Signal file descriptor. */
  53         int sigfd;
  54
  55         /* List of file descriptors referring to the namespaces of the
  56          * container. Note that these are not necessarily identical to
  57          * the "clone_flags" handler field in case namespace inheritance is
  58          * requested.
  59          */
  60         int nsfd[LXC_NS_MAX];
  61
  62         /* Abstract unix domain SOCK_DGRAM socketpair to pass arbitrary data
  63          * between child and parent.
  64          */
  65         int data_sock[2];
  66
  67         /* The socketpair() fds used to wait on successful daemonized startup. */
  68         int state_socket_pair[2];
  69
  70         /* Socketpair to synchronize processes during container creation. */
  71         int sync_sock[2];
  72
  73         /* Pointer to the name of the container. Do not free! */
  74         const char *name;
  75
  76         /* Pointer to the path the container. Do not free! */
  77         const char *lxcpath;
  78
  79         /* Whether the container's startup process euid is 0. */
  80         bool am_root;
  81
  82         /* Indicates whether should we close std{in,out,err} on start. */
  83         bool backgrounded;
  84
  85         /* The child's pid. */
  86         pid_t pid;
  87
  88         /* Whether the child has already exited. */
  89         bool init_died;
  90
  91         /* The signal mask prior to setting up the signal file descriptor. */
  92         sigset_t oldmask;
  93
  94         /* The container's in-memory configuration. */
  95         struct lxc_conf *conf;
  96
  97         /* A set of operations to be performed at various stages of the
  98          * container's life.
  99          */
 100         struct lxc_operations *ops;
 101
 102         /* This holds the cgroup information. Note that the data here is
 103          * specific to the cgroup driver used.
 104          */
 105         void *cgroup_data;
 106
 107         /* Data to be passed to handler ops. */
 108         void *data;
 109
 110         /* Current state of the container. */
 111         lxc_state_t state;
 112
 113         /* The exit status of the container; not defined unless ->init_died ==
 114          * true.
 115          */
 116         int exit_status;
 117 };
 118
 119 struct lxc_operations {
 120         int (*start)(struct lxc_handler *, void *);
 121         int (*post_start)(struct lxc_handler *, void *);
 122 };
 123
 124 extern int lxc_poll(const char *name, struct lxc_handler *handler);
 125 extern int lxc_set_state(const char *name, struct lxc_handler *handler,
 126                          lxc_state_t state);
 127 extern int lxc_serve_state_clients(const char *name,
 128                                    struct lxc_handler *handler,
 129                                    lxc_state_t state);
 130 extern void lxc_abort(const char *name, struct lxc_handler *handler);
 131 extern struct lxc_handler *lxc_init_handler(const char *name,
 132                                             struct lxc_conf *conf,
 133                                             const char *lxcpath,
 134                                             bool daemonize);
 135 extern void lxc_zero_handler(struct lxc_handler *handler);
 136 extern void lxc_free_handler(struct lxc_handler *handler);
 137 extern int lxc_init(const char *name, struct lxc_handler *handler);
 138 extern void lxc_fini(const char *name, struct lxc_handler *handler);
 139
 140 /* lxc_check_inherited: Check for any open file descriptors and close them if
 141  *                      requested.
 142  * @param[in] conf          The container's configuration.
 143  * @param[in] closeall      Whether we should close all open file descriptors.
 144  * @param[in] fds_to_ignore Array of file descriptors to ignore.
 145  * @param[in] len_fds       Length of fds_to_ignore array.
 146  */
 147 extern int lxc_check_inherited(struct lxc_conf *conf, bool closeall,
 148                                int *fds_to_ignore, size_t len_fds);
 149 extern int __lxc_start(const char *, struct lxc_handler *,
 150                        struct lxc_operations *, void *, const char *, bool);
 151
 152 extern int resolve_clone_flags(struct lxc_handler *handler);
 153
 154 #endif