plugin.h

mysql sdk

/* Copyright (C) 2005 MySQL AB

   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; version 2 of the License.

   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

#ifndef _my_plugin_h
#define _my_plugin_h

#ifdef __cplusplus
class THD;
class Item;
#define MYSQL_THD THD*
#else
#define MYSQL_THD void*
#endif

#ifndef _m_string_h
/* This definition must match the one given in m_string.h */
struct st_mysql_lex_string
{
  char *str;
  unsigned int length;
};
#endif /* _m_string_h */
typedef struct st_mysql_lex_string MYSQL_LEX_STRING;

#define MYSQL_XIDDATASIZE 128
/**
  struct st_mysql_xid is binary compatible with the XID structure as
  in the X/Open CAE Specification, Distributed Transaction Processing:
  The XA Specification, X/Open Company Ltd., 1991.
  http://www.opengroup.org/bookstore/catalog/c193.htm

  @see XID in sql/handler.h
*/
struct st_mysql_xid {
  long formatID;
  long gtrid_length;
  long bqual_length;
  char data[MYSQL_XIDDATASIZE];  /* Not \0-terminated */
};
typedef struct st_mysql_xid MYSQL_XID;

/*************************************************************************
  Plugin API. Common for all plugin types.
*/

#define MYSQL_PLUGIN_INTERFACE_VERSION 0x0100

/*
  The allowable types of plugins
*/
#define MYSQL_UDF_PLUGIN             0  /* User-defined function        */
#define MYSQL_STORAGE_ENGINE_PLUGIN  1  /* Storage Engine               */
#define MYSQL_FTPARSER_PLUGIN        2  /* Full-text parser plugin      */
#define MYSQL_DAEMON_PLUGIN          3  /* The daemon/raw plugin type */
#define MYSQL_INFORMATION_SCHEMA_PLUGIN  4  /* The I_S plugin type */
#define MYSQL_MAX_PLUGIN_TYPE_NUM    5  /* The number of plugin types   */

/* We use the following strings to define licenses for plugins */
#define PLUGIN_LICENSE_PROPRIETARY 0
#define PLUGIN_LICENSE_GPL 1
#define PLUGIN_LICENSE_BSD 2

#define PLUGIN_LICENSE_PROPRIETARY_STRING "PROPRIETARY"
#define PLUGIN_LICENSE_GPL_STRING "GPL"
#define PLUGIN_LICENSE_BSD_STRING "BSD"

/*
  Macros for beginning and ending plugin declarations.  Between
  mysql_declare_plugin and mysql_declare_plugin_end there should
  be a st_mysql_plugin struct for each plugin to be declared.
*/


#ifndef MYSQL_DYNAMIC_PLUGIN
#define __MYSQL_DECLARE_PLUGIN(NAME, VERSION, PSIZE, DECLS)                   \
int VERSION= MYSQL_PLUGIN_INTERFACE_VERSION;                                  \
int PSIZE= sizeof(struct st_mysql_plugin);                                    \
struct st_mysql_plugin DECLS[]= {
#else
#define __MYSQL_DECLARE_PLUGIN(NAME, VERSION, PSIZE, DECLS)                   \
int _mysql_plugin_interface_version_= MYSQL_PLUGIN_INTERFACE_VERSION;         \
int _mysql_sizeof_struct_st_plugin_= sizeof(struct st_mysql_plugin);          \
struct st_mysql_plugin _mysql_plugin_declarations_[]= {
#endif

#define mysql_declare_plugin(NAME) \
__MYSQL_DECLARE_PLUGIN(NAME, \
                 builtin_ ## NAME ## _plugin_interface_version, \
                 builtin_ ## NAME ## _sizeof_struct_st_plugin, \
                 builtin_ ## NAME ## _plugin)

#define mysql_declare_plugin_end ,{0,0,0,0,0,0,0,0,0,0,0,0}}

/*
  declarations for SHOW STATUS support in plugins
*/
enum enum_mysql_show_type
{
  SHOW_UNDEF, SHOW_BOOL, SHOW_INT, SHOW_LONG,
  SHOW_LONGLONG, SHOW_CHAR, SHOW_CHAR_PTR,
  SHOW_ARRAY, SHOW_FUNC, SHOW_DOUBLE
};

struct st_mysql_show_var {
  const char *name;
  char *value;
  enum enum_mysql_show_type type;
};

#define SHOW_VAR_FUNC_BUFF_SIZE 1024
typedef int (*mysql_show_var_func)(MYSQL_THD, struct st_mysql_show_var*, char *);


/*
  declarations for server variables and command line options
*/


#define PLUGIN_VAR_BOOL         0x0001
#define PLUGIN_VAR_INT          0x0002
#define PLUGIN_VAR_LONG         0x0003
#define PLUGIN_VAR_LONGLONG     0x0004
#define PLUGIN_VAR_STR          0x0005
#define PLUGIN_VAR_ENUM         0x0006
#define PLUGIN_VAR_SET          0x0007
#define PLUGIN_VAR_UNSIGNED     0x0080
#define PLUGIN_VAR_THDLOCAL     0x0100 /* Variable is per-connection */
#define PLUGIN_VAR_READONLY     0x0200 /* Server variable is read only */
#define PLUGIN_VAR_NOSYSVAR     0x0400 /* Not a server variable */
#define PLUGIN_VAR_NOCMDOPT     0x0800 /* Not a command line option */
#define PLUGIN_VAR_NOCMDARG     0x1000 /* No argument for cmd line */
#define PLUGIN_VAR_RQCMDARG     0x0000 /* Argument required for cmd line */
#define PLUGIN_VAR_OPCMDARG     0x2000 /* Argument optional for cmd line */
#define PLUGIN_VAR_MEMALLOC     0x8000 /* String needs memory allocated */

struct st_mysql_sys_var;
struct st_mysql_value;

/*
  SYNOPSIS
    (*mysql_var_check_func)()
      thd               thread handle
      var               dynamic variable being altered
      save              pointer to temporary storage
      value             user provided value
  RETURN
    0   user provided value is OK and the update func may be called.
    any other value indicates error.
  
  This function should parse the user provided value and store in the
  provided temporary storage any data as required by the update func.
  There is sufficient space in the temporary storage to store a double.
  Note that the update func may not be called if any other error occurs
  so any memory allocated should be thread-local so that it may be freed
  automatically at the end of the statement.
*/

typedef int (*mysql_var_check_func)(MYSQL_THD thd,
                                    struct st_mysql_sys_var *var,
                                    void *save, struct st_mysql_value *value);

/*
  SYNOPSIS
    (*mysql_var_update_func)()
      thd               thread handle
      var               dynamic variable being altered
      var_ptr           pointer to dynamic variable
      save              pointer to temporary storage
   RETURN
     NONE
   
   This function should use the validated value stored in the temporary store
   and persist it in the provided pointer to the dynamic variable.
   For example, strings may require memory to be allocated.
*/
typedef void (*mysql_var_update_func)(MYSQL_THD thd,
                                      struct st_mysql_sys_var *var,
                                      void *var_ptr, const void *save);


/* the following declarations are for internal use only */


#define PLUGIN_VAR_MASK \
        (PLUGIN_VAR_READONLY | PLUGIN_VAR_NOSYSVAR | \
         PLUGIN_VAR_NOCMDOPT | PLUGIN_VAR_NOCMDARG | \
         PLUGIN_VAR_OPCMDARG | PLUGIN_VAR_RQCMDARG | PLUGIN_VAR_MEMALLOC)

#define MYSQL_PLUGIN_VAR_HEADER \
  int flags;                    \
  const char *name;             \
  const char *comment;          \
  mysql_var_check_func check;   \
  mysql_var_update_func update

#define MYSQL_SYSVAR_NAME(name) mysql_sysvar_ ## name
#define MYSQL_SYSVAR(name) \
  ((struct st_mysql_sys_var *)&(MYSQL_SYSVAR_NAME(name)))

/*
  for global variables, the value pointer is the first
  element after the header, the default value is the second.
  for thread variables, the value offset is the first
  element after the header, the default value is the second.
*/
   

#define DECLARE_MYSQL_SYSVAR_BASIC(name, type) struct { \
  MYSQL_PLUGIN_VAR_HEADER;      \
  type *value;                  \
  const type def_val;           \
} MYSQL_SYSVAR_NAME(name)

#define DECLARE_MYSQL_SYSVAR_SIMPLE(name, type) struct { \
  MYSQL_PLUGIN_VAR_HEADER;      \
  type *value; type def_val;    \
  type min_val; type max_val;   \
  type blk_sz;                  \
} MYSQL_SYSVAR_NAME(name)

#define DECLARE_MYSQL_SYSVAR_TYPELIB(name, type) struct { \
  MYSQL_PLUGIN_VAR_HEADER;      \
  type *value; type def_val;    \
  TYPELIB *typelib;             \
} MYSQL_SYSVAR_NAME(name)

#define DECLARE_THDVAR_FUNC(type) \
  type *(*resolve)(MYSQL_THD thd, int offset)

#define DECLARE_MYSQL_THDVAR_BASIC(name, type) struct { \
  MYSQL_PLUGIN_VAR_HEADER;      \
  int offset;                   \
  const type def_val;           \
  DECLARE_THDVAR_FUNC(type);    \
} MYSQL_SYSVAR_NAME(name)

#define DECLARE_MYSQL_THDVAR_SIMPLE(name, type) struct { \
  MYSQL_PLUGIN_VAR_HEADER;      \
  int offset;                   \
  type def_val; type min_val;   \
  type max_val; type blk_sz;    \
  DECLARE_THDVAR_FUNC(type);    \
} MYSQL_SYSVAR_NAME(name)

#define DECLARE_MYSQL_THDVAR_TYPELIB(name, type) struct { \
  MYSQL_PLUGIN_VAR_HEADER;      \
  int offset;                   \
  type def_val;                 \
  DECLARE_THDVAR_FUNC(type);    \
  TYPELIB *typelib;             \
} MYSQL_SYSVAR_NAME(name)


/*
  the following declarations are for use by plugin implementors
*/

#define MYSQL_SYSVAR_BOOL(name, varname, opt, comment, check, update, def) \
DECLARE_MYSQL_SYSVAR_BASIC(name, char) = { \
  PLUGIN_VAR_BOOL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def}

#define MYSQL_SYSVAR_STR(name, varname, opt, comment, check, update, def) \
DECLARE_MYSQL_SYSVAR_BASIC(name, char *) = { \
  PLUGIN_VAR_STR | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def}

#define MYSQL_SYSVAR_INT(name, varname, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_SYSVAR_SIMPLE(name, int) = { \
  PLUGIN_VAR_INT | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, min, max, blk }

#define MYSQL_SYSVAR_UINT(name, varname, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_SYSVAR_SIMPLE(name, unsigned int) = { \
  PLUGIN_VAR_INT | PLUGIN_VAR_UNSIGNED | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, min, max, blk }

#define MYSQL_SYSVAR_LONG(name, varname, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_SYSVAR_SIMPLE(name, long) = { \
  PLUGIN_VAR_LONG | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, min, max, blk }

#define MYSQL_SYSVAR_ULONG(name, varname, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_SYSVAR_SIMPLE(name, unsigned long) = { \
  PLUGIN_VAR_LONG | PLUGIN_VAR_UNSIGNED | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, min, max, blk }

#define MYSQL_SYSVAR_LONGLONG(name, varname, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_SYSVAR_SIMPLE(name, long long) = { \
  PLUGIN_VAR_LONGLONG | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, min, max, blk }

#define MYSQL_SYSVAR_ULONGLONG(name, varname, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_SYSVAR_SIMPLE(name, unsigned long long) = { \
  PLUGIN_VAR_LONGLONG | PLUGIN_VAR_UNSIGNED | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, min, max, blk }

#define MYSQL_SYSVAR_ENUM(name, varname, opt, comment, check, update, def, typelib) \
DECLARE_MYSQL_SYSVAR_TYPELIB(name, unsigned long) = { \
  PLUGIN_VAR_ENUM | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, typelib }

#define MYSQL_SYSVAR_SET(name, varname, opt, comment, check, update, def, typelib) \
DECLARE_MYSQL_SYSVAR_TYPELIB(name, unsigned long long) = { \
  PLUGIN_VAR_SET | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, &varname, def, typelib }

#define MYSQL_THDVAR_BOOL(name, opt, comment, check, update, def) \
DECLARE_MYSQL_THDVAR_BASIC(name, char) = { \
  PLUGIN_VAR_BOOL | PLUGIN_VAR_THDLOCAL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, NULL}

#define MYSQL_THDVAR_STR(name, opt, comment, check, update, def) \
DECLARE_MYSQL_THDVAR_BASIC(name, char *) = { \
  PLUGIN_VAR_STR | PLUGIN_VAR_THDLOCAL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, NULL}

#define MYSQL_THDVAR_INT(name, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_THDVAR_SIMPLE(name, int) = { \
  PLUGIN_VAR_INT | PLUGIN_VAR_THDLOCAL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, min, max, blk, NULL }

#define MYSQL_THDVAR_UINT(name, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_THDVAR_SIMPLE(name, unsigned int) = { \
  PLUGIN_VAR_INT | PLUGIN_VAR_THDLOCAL | PLUGIN_VAR_UNSIGNED | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, min, max, blk, NULL }

#define MYSQL_THDVAR_LONG(name, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_THDVAR_SIMPLE(name, long) = { \
  PLUGIN_VAR_LONG | PLUGIN_VAR_THDLOCAL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, min, max, blk, NULL }

#define MYSQL_THDVAR_ULONG(name, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_THDVAR_SIMPLE(name, unsigned long) = { \
  PLUGIN_VAR_LONG | PLUGIN_VAR_THDLOCAL | PLUGIN_VAR_UNSIGNED | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, min, max, blk, NULL }

#define MYSQL_THDVAR_LONGLONG(name, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_THDVAR_SIMPLE(name, long long) = { \
  PLUGIN_VAR_LONGLONG | PLUGIN_VAR_THDLOCAL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, min, max, blk, NULL }

#define MYSQL_THDVAR_ULONGLONG(name, opt, comment, check, update, def, min, max, blk) \
DECLARE_MYSQL_THDVAR_SIMPLE(name, unsigned long long) = { \
  PLUGIN_VAR_LONGLONG | PLUGIN_VAR_THDLOCAL | PLUGIN_VAR_UNSIGNED | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, min, max, blk, NULL }

#define MYSQL_THDVAR_ENUM(name, opt, comment, check, update, def, typelib) \
DECLARE_MYSQL_THDVAR_TYPELIB(name, unsigned long) = { \
  PLUGIN_VAR_ENUM | PLUGIN_VAR_THDLOCAL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, NULL, typelib }

#define MYSQL_THDVAR_SET(name, opt, comment, check, update, def, typelib) \
DECLARE_MYSQL_THDVAR_TYPELIB(name, unsigned long long) = { \
  PLUGIN_VAR_SET | PLUGIN_VAR_THDLOCAL | ((opt) & PLUGIN_VAR_MASK), \
  #name, comment, check, update, -1, def, NULL, typelib }

/* accessor macros */

#define SYSVAR(name) \
  (*(MYSQL_SYSVAR_NAME(name).value))

/* when thd == null, result points to global value */
#define THDVAR(thd, name) \
  (*(MYSQL_SYSVAR_NAME(name).resolve(thd, MYSQL_SYSVAR_NAME(name).offset)))


/*
  Plugin description structure.
*/

struct st_mysql_plugin
{
  int type;             /* the plugin type (a MYSQL_XXX_PLUGIN value)   */
  void *info;           /* pointer to type-specific plugin descriptor   */
  const char *name;     /* plugin name                                  */
  const char *author;   /* plugin author (for SHOW PLUGINS)             */
  const char *descr;    /* general descriptive text (for SHOW PLUGINS ) */
  int license;          /* the plugin license (PLUGIN_LICENSE_XXX)      */
  int (*init)(void *);  /* the function to invoke when plugin is loaded */
  int (*deinit)(void *);/* the function to invoke when plugin is unloaded */
  unsigned int version; /* plugin version (for SHOW PLUGINS)            */
  struct st_mysql_show_var *status_vars;
  struct st_mysql_sys_var **system_vars;
  void * __reserved1;   /* reserved for dependency checking             */
};

/*************************************************************************
  API for Full-text parser plugin. (MYSQL_FTPARSER_PLUGIN)
*/

#define MYSQL_FTPARSER_INTERFACE_VERSION 0x0100

/* Parsing modes. Set in  MYSQL_FTPARSER_PARAM::mode */
enum enum_ftparser_mode
{
/*
  Fast and simple mode.  This mode is used for indexing, and natural
  language queries.