/*
* This file defines types and macros for CRIU plugins.
* Copyright (C) 2013-2014 Parallels, Inc
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*/

#ifndef __CRIU_PLUGIN_H__
#define __CRIU_PLUGIN_H__

#include <limits.h>
#include <stdbool.h>

#define CRIU_PLUGIN_GEN_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
#define CRIU_PLUGIN_VERSION_MAJOR 0
#define CRIU_PLUGIN_VERSION_MINOR 2
#define CRIU_PLUGIN_VERSION_SUBLEVEL 0

#define CRIU_PLUGIN_VERSION_OLD CRIU_PLUGIN_GEN_VERSION(0,1,0)

#define CRIU_PLUGIN_VERSION \
CRIU_PLUGIN_GEN_VERSION(CRIU_PLUGIN_VERSION_MAJOR, \
CRIU_PLUGIN_VERSION_MINOR, \
CRIU_PLUGIN_VERSION_SUBLEVEL)

/*
* Plugin hook points and their arguments in hooks.
*/
enum {
CR_PLUGIN_HOOK__DUMP_UNIX_SK = 0,
CR_PLUGIN_HOOK__RESTORE_UNIX_SK = 1,

CR_PLUGIN_HOOK__DUMP_EXT_FILE = 2,
CR_PLUGIN_HOOK__RESTORE_EXT_FILE = 3,

CR_PLUGIN_HOOK__DUMP_EXT_MOUNT = 4,
CR_PLUGIN_HOOK__RESTORE_EXT_MOUNT = 5,

CR_PLUGIN_HOOK__DUMP_EXT_LINK = 6,

CR_PLUGIN_HOOK__MAX
};

#define DECLARE_PLUGIN_HOOK_ARGS(__hook, ...) \
typedef int (__hook ##_t)(__VA_ARGS__)

DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__DUMP_UNIX_SK, int fd, int id);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__RESTORE_UNIX_SK, int id);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__DUMP_EXT_FILE, int fd, int id);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__RESTORE_EXT_FILE, int id);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__DUMP_EXT_MOUNT, char *mountpoint, int id);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__RESTORE_EXT_MOUNT, int id, char *mountpoint, char *old_root, int *is_file);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__DUMP_EXT_LINK, int index, int type, char *kind);

enum {
CR_PLUGIN_STAGE__DUMP,
CR_PLUGIN_STAGE__PRE_DUMP,
CR_PLUGIN_STAGE__RESTORE,

CR_PLUGIN_STAGE_MAX
};

/*
* Plugin descriptor.
*/
typedef struct {
const char *name;
int (*init)(int stage);
void (*exit)(int stage, int ret);
unsigned int version;
unsigned int max_hooks;
void *hooks[CR_PLUGIN_HOOK__MAX];
} cr_plugin_desc_t;

extern cr_plugin_desc_t CR_PLUGIN_DESC;

#define CR_PLUGIN_REGISTER(___name, ___init, ___exit) \
cr_plugin_desc_t CR_PLUGIN_DESC = { \
.name = ___name, \
.init = ___init, \
.exit = ___exit, \
.version = CRIU_PLUGIN_VERSION, \
.max_hooks = CR_PLUGIN_HOOK__MAX, \
};

static inline int cr_plugin_dummy_init(int stage) { return 0; }
static inline void cr_plugin_dummy_exit(int stage, int ret) { }

#define CR_PLUGIN_REGISTER_DUMMY(___name) \
cr_plugin_desc_t CR_PLUGIN_DESC = { \
.name = ___name, \
.init = cr_plugin_dummy_init, \
.exit = cr_plugin_dummy_exit, \
.version = CRIU_PLUGIN_VERSION, \
.max_hooks = CR_PLUGIN_HOOK__MAX, \
};

#define CR_PLUGIN_REGISTER_HOOK(__hook, __func) \
static void __attribute__((constructor)) cr_plugin_register_hook_##__func (void) \
{ \
CR_PLUGIN_DESC.hooks[__hook] = (void *)__func; \
}

/* Public API */
extern int criu_get_image_dir(void);

/*
* Deprecated, will be removed in next version.
*/
typedef int (cr_plugin_init_t)(void);
typedef void (cr_plugin_fini_t)(void);
typedef int (cr_plugin_dump_unix_sk_t)(int fd, int id);
typedef int (cr_plugin_restore_unix_sk_t)(int id);
typedef int (cr_plugin_dump_file_t)(int fd, int id);
typedef int (cr_plugin_restore_file_t)(int id);
typedef int (cr_plugin_dump_ext_mount_t)(char *mountpoint, int id);
typedef int (cr_plugin_restore_ext_mount_t)(int id, char *mountpoint, char *old_root, int *is_file);
typedef int (cr_plugin_dump_ext_link_t)(int index, int type, char *kind);

#endif /* __CRIU_PLUGIN_H__ */