/*
 *  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>
#include <stdint.h>
#include <sys/stat.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__HANDLE_DEVICE_VMA = 7,

	CR_PLUGIN_HOOK__UPDATE_VMA_MAP = 8,

	CR_PLUGIN_HOOK__RESUME_DEVICES_LATE = 9,

	CR_PLUGIN_HOOK__PAUSE_DEVICES = 10,

	CR_PLUGIN_HOOK__CHECKPOINT_DEVICES = 11,

	CR_PLUGIN_HOOK__POST_FORKING = 12,

	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);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__HANDLE_DEVICE_VMA, int fd, const struct stat *stat);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__UPDATE_VMA_MAP, const char *path, const uint64_t addr,
			 const uint64_t old_pgoff, uint64_t *new_pgoff, int *plugin_fd);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__RESUME_DEVICES_LATE, int pid);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__PAUSE_DEVICES, int pid);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__CHECKPOINT_DEVICES, int pid);
DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__POST_FORKING, void);

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);
typedef int(cr_plugin_handle_device_vma_t)(int fd, const struct stat *stat);
typedef int(cr_plugin_update_vma_map_t)(const char *path, const uint64_t addr, const uint64_t old_pgoff,
					uint64_t *new_pgoff, int *plugin_fd);
typedef int(cr_plugin_resume_devices_late_t)(int pid);
typedef int(cr_plugin_post_forking_t)(void);

#endif /* __CRIU_PLUGIN_H__ */