/* Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   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, version 2.0, 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,
   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

#ifndef _sql_plugin_h
#define _sql_plugin_h

#include <my_global.h>
#include <vector>

/**
  the following #define adds server-only members to enum_mysql_show_type,
  that is defined in plugin.h.
*/
#define SHOW_always_last SHOW_KEY_CACHE_LONG, \
            SHOW_KEY_CACHE_LONGLONG, SHOW_LONG_STATUS, SHOW_DOUBLE_STATUS, \
            SHOW_HAVE, SHOW_MY_BOOL, SHOW_HA_ROWS, SHOW_SYS, \
            SHOW_LONG_NOFLUSH, SHOW_LONGLONG_STATUS, SHOW_LEX_STRING, \
            SHOW_SIGNED_LONG
#include <mysql/plugin.h>
#undef SHOW_always_last

#include "m_string.h"                       /* LEX_STRING */
#include "my_alloc.h"                       /* MEM_ROOT */
#include "my_getopt.h"                      /* my_option */

class sys_var;
enum SHOW_COMP_OPTION { SHOW_OPTION_YES, SHOW_OPTION_NO, SHOW_OPTION_DISABLED};
enum enum_plugin_load_option { PLUGIN_OFF, PLUGIN_ON, PLUGIN_FORCE,
  PLUGIN_FORCE_PLUS_PERMANENT };
extern const char *global_plugin_typelib_names[];
extern mysql_mutex_t LOCK_plugin_delete;

#include <my_sys.h>
#include "sql_list.h"

#ifdef DBUG_OFF
#define plugin_ref_to_int(A) A
#define plugin_int_to_ref(A) A
#else
#define plugin_ref_to_int(A) (A ? A[0] : NULL)
#define plugin_int_to_ref(A) &(A)
#endif

/*
  the following flags are valid for plugin_init()
*/
#define PLUGIN_INIT_SKIP_DYNAMIC_LOADING 1
#define PLUGIN_INIT_SKIP_PLUGIN_TABLE    2
#define PLUGIN_INIT_SKIP_INITIALIZATION  4

#define INITIAL_LEX_PLUGIN_LIST_SIZE    16

typedef enum enum_mysql_show_type SHOW_TYPE;
typedef struct st_mysql_show_var SHOW_VAR;
typedef struct st_mysql_lex_string LEX_STRING;

#define MYSQL_ANY_PLUGIN         -1

/*
  different values of st_plugin_int::state
  though they look like a bitmap, plugin may only
  be in one of those eigenstates, not in a superposition of them :)
  It's a bitmap, because it makes it easier to test
  "whether the state is one of those..."
*/
#define PLUGIN_IS_FREED         1
#define PLUGIN_IS_DELETED       2
#define PLUGIN_IS_UNINITIALIZED 4
#define PLUGIN_IS_READY         8
#define PLUGIN_IS_DYING         16
#define PLUGIN_IS_DISABLED      32

/* A handle for the dynamic library containing a plugin or plugins. */

struct st_plugin_dl
{
  LEX_STRING dl;
  void *handle;
  struct st_mysql_plugin *plugins;
  int version;
  uint ref_count;            /* number of plugins loaded from the library */
};

/* A handle of a plugin */

struct st_plugin_int
{
  LEX_STRING name;
  struct st_mysql_plugin *plugin;
  struct st_plugin_dl *plugin_dl;
  uint state;
  uint ref_count;               /* number of threads using the plugin */
  void *data;                   /* plugin type specific, e.g. handlerton */
  MEM_ROOT mem_root;            /* memory for dynamic plugin structures */
  sys_var *system_vars;         /* server variables for this plugin */
  enum enum_plugin_load_option load_option; /* OFF, ON, FORCE, F+PERMANENT */
};


/*
  See intern_plugin_lock() for the explanation for the
  conditionally defined plugin_ref type
*/
#ifdef DBUG_OFF
typedef struct st_plugin_int *plugin_ref;
#define plugin_decl(pi) ((pi)->plugin)
#define plugin_dlib(pi) ((pi)->plugin_dl)
#define plugin_data(pi,cast) ((cast)((pi)->data))
#define plugin_name(pi) (&((pi)->name))
#define plugin_state(pi) ((pi)->state)
#define plugin_load_option(pi) ((pi)->load_option)
#define plugin_equals(p1,p2) ((p1) == (p2))
#else
typedef struct st_plugin_int **plugin_ref;
#define plugin_decl(pi) ((pi)[0]->plugin)
#define plugin_dlib(pi) ((pi)[0]->plugin_dl)
#define plugin_data(pi,cast) ((cast)((pi)[0]->data))
#define plugin_name(pi) (&((pi)[0]->name))
#define plugin_state(pi) ((pi)[0]->state)
#define plugin_load_option(pi) ((pi)[0]->load_option)
#define plugin_equals(p1,p2) ((p1) && (p2) && (p1)[0] == (p2)[0])
#endif

typedef int (*plugin_type_init)(struct st_plugin_int *);

extern I_List<i_string> *opt_plugin_load_list_ptr;
extern char *opt_plugin_dir_ptr;
extern char opt_plugin_dir[FN_REFLEN];
extern const LEX_STRING plugin_type_names[];

extern int plugin_init(int *argc, char **argv, int init_flags);
extern void plugin_shutdown(void);
extern void memcached_shutdown(void);
void add_plugin_options(std::vector<my_option> *options, MEM_ROOT *mem_root);
extern bool plugin_is_ready(const LEX_STRING *name, int type);
#define my_plugin_lock_by_name(A,B,C) plugin_lock_by_name(A,B,C)
#define my_plugin_lock_by_name_ci(A,B,C) plugin_lock_by_name(A,B,C)
#define my_plugin_lock(A,B) plugin_lock(A,B)
#define my_plugin_lock_ci(A,B) plugin_lock(A,B)
extern plugin_ref plugin_lock(THD *thd, plugin_ref *ptr);
extern plugin_ref plugin_lock_by_name(THD *thd, const LEX_STRING *name,
                                      int type);
extern void plugin_unlock(THD *thd, plugin_ref plugin);
extern void plugin_unlock_list(THD *thd, plugin_ref *list, uint count);
extern bool mysql_install_plugin(THD *thd, const LEX_STRING *name,
                                 const LEX_STRING *dl);
extern bool mysql_uninstall_plugin(THD *thd, const LEX_STRING *name);
extern bool plugin_register_builtin(struct st_mysql_plugin *plugin);
extern void plugin_thdvar_init(THD *thd, bool enable_plugins);
extern void plugin_thdvar_cleanup(THD *thd);
extern SHOW_COMP_OPTION plugin_status(const char *name, size_t len, int type);
extern bool check_valid_path(const char *path, size_t length);

typedef my_bool (plugin_foreach_func)(THD *thd,
                                      plugin_ref plugin,
                                      void *arg);
#define plugin_foreach(A,B,C,D) plugin_foreach_with_mask(A,B,C,PLUGIN_IS_READY,D)
extern bool plugin_foreach_with_mask(THD *thd, plugin_foreach_func *func,
                                     int type, uint state_mask, void *arg);

/* interface to randomly access plugin data */
struct st_plugin_int *plugin_find_by_type(LEX_STRING *plugin, int type);
int lock_plugin_data();
int unlock_plugin_data();
#endif
