MySQL 8.4.3
Source Code Documentation
sql_udf.h
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1#ifndef SQL_UDF_INCLUDED
2#define SQL_UDF_INCLUDED
3
4/* Copyright (c) 2000, 2024, Oracle and/or its affiliates.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License, version 2.0,
8 as published by the Free Software Foundation.
9
10 This program is designed to work with certain software (including
11 but not limited to OpenSSL) that is licensed under separate terms,
12 as designated in a particular file or component or in included license
13 documentation. The authors of MySQL hereby grant you an additional
14 permission to link the program and your derivative works with the
15 separately licensed software that they have either included with
16 the program or referenced in the documentation.
17
18 This program is distributed in the hope that it will be useful,
19 but WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 GNU General Public License, version 2.0, for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with this program; if not, write to the Free Software
25 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
26
27/* This file defines structures needed by udf functions */
28
29#include <stddef.h>
30#include <sys/types.h>
31
32#include "lex_string.h"
33#include "my_inttypes.h"
34#include "my_table_map.h"
36
37class Item;
39class String;
40class THD;
41class my_decimal;
42struct CHARSET_INFO;
43
44struct udf_func {
48 char *dl;
49 void *dlhandle;
56};
57
58/*
59 A structure of extension attributes for a UDF argument.
60 The extension pointer of UDF_ARGS may point to the object of this
61 structure. There are udf_extension component services to set and get
62 the extension attributes of argument.
63*/
67};
68
69/*
70 A structure of extension attributes for return value of UDF.
71 The extension pointer of UDF_INIT may point to the object of this
72 structure. There are udf_extension component services to set and get
73 the extension attributes of return value.
74*/
81};
82
84 protected:
86 String *buffers{nullptr};
89 char *num_buffer{nullptr};
92 /// True when handler has been initialized and use count incremented
93 bool m_initialized{false};
94 /// True when init function has been called
95 bool m_init_func_called{false};
97 Udf_args_extension m_args_extension; /**< A struct that holds the extension
98 arguments for each UDF argument */
100 m_return_value_extension; /**< A struct that holds the extension arguments
101 for return value */
102 public:
104 bool m_original{true};
105
106 udf_handler(udf_func *udf_arg);
107 udf_handler(const udf_handler &) = default;
109 udf_handler &operator=(const udf_handler &) = default;
111 // Clean up string buffers
112 void clean_buffers();
113 void free_handler();
114
115 bool is_initialized() const { return m_initialized; }
116
117 const char *name() const { return u_d ? u_d->name.str : "?"; }
119 return (Item_result)(u_d ? (u_d->returns) : STRING_RESULT);
120 }
121 bool fix_fields(THD *thd, Item_result_field *item, uint arg_count,
122 Item **args);
123 void cleanup();
124 bool call_init_func();
125 double val_real(bool *null_value);
126 longlong val_int(bool *null_value);
127 my_decimal *val_decimal(bool *null_value, my_decimal *dec_buf);
128 String *val_str(String *str, String *save_str);
129 void clear();
130 void add(bool *null_value);
131
132 private:
133 bool get_arguments();
134 String *result_string(const char *res, size_t res_length, String *str,
135 String *save_str);
136 void get_string(uint index);
137 bool get_and_convert_string(uint index);
138};
139
140void udf_init_globals();
142void udf_unload_udfs();
143void udf_deinit_globals();
144udf_func *find_udf(const char *name, size_t len = 0, bool mark_used = false);
145void free_udf(udf_func *udf);
146bool mysql_create_function(THD *thd, udf_func *udf, bool if_not_exists);
147bool mysql_drop_function(THD *thd, const LEX_STRING *name);
148ulong udf_hash_size(void);
149void udf_hash_rlock(void);
150void udf_hash_unlock(void);
151typedef void udf_hash_for_each_func_t(udf_func *, void *);
152void udf_hash_for_each(udf_hash_for_each_func_t *func, void *arg);
153#endif /* SQL_UDF_INCLUDED */
Kerberos Client Authentication nullptr
Definition: auth_kerberos_client_plugin.cc:251
Item with result field.
Definition: item.h:5811
Base class that is used to represent any kind of expression in a relational query.
Definition: item.h:936
Using this class is fraught with peril, and you need to be very careful when doing so.
Definition: sql_string.h:167
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_lexer_thd.h:36
my_decimal class limits 'decimal_t' type to what we need in MySQL.
Definition: my_decimal.h:95
Definition: sql_udf.h:83
bool m_init_func_called
True when init function has been called.
Definition: sql_udf.h:95
bool get_and_convert_string(uint index)
Get the details of the input String argument.
Definition: item_func.cc:4979
Item_result result_type() const
Definition: sql_udf.h:118
bool call_init_func()
Definition: item_func.cc:4718
const char * name() const
Definition: sql_udf.h:117
table_map used_tables_cache
Definition: sql_udf.h:103
my_decimal * val_decimal(bool *null_value, my_decimal *dec_buf)
Definition: item_func.cc:4886
udf_handler(udf_handler &&)=default
UDF_INIT initid
Definition: sql_udf.h:88
longlong val_int(bool *null_value)
Definition: item_func.cc:4830
bool m_initialized
True when handler has been initialized and use count incremented.
Definition: sql_udf.h:93
uchar is_null
Definition: sql_udf.h:91
void get_string(uint index)
Get the details of the input String arguments.
Definition: item_func.cc:4959
udf_handler & operator=(const udf_handler &)=default
bool is_initialized() const
Definition: sql_udf.h:115
char * num_buffer
Definition: sql_udf.h:89
bool m_original
Definition: sql_udf.h:104
bool fix_fields(THD *thd, Item_result_field *item, uint arg_count, Item **args)
Definition: item_func.cc:4554
Item ** args
Definition: sql_udf.h:96
void cleanup()
Definition: item_func.cc:4507
String * result_string(const char *res, size_t res_length, String *str, String *save_str)
Process the result string returned by the udf() method.
Definition: item_func.cc:4939
UDF_ARGS f_args
Definition: sql_udf.h:87
uchar error
Definition: sql_udf.h:90
void clear()
Definition: item_func.cc:4908
String * val_str(String *str, String *save_str)
Definition: item_func.cc:4852
double val_real(bool *null_value)
Definition: item_func.cc:4813
void free_handler()
Definition: item_func.cc:4535
String * buffers
Definition: sql_udf.h:86
udf_handler(udf_func *udf_arg)
Definition: item_func.cc:4502
void clean_buffers()
Definition: item_func.cc:4528
udf_handler(const udf_handler &)=default
bool get_arguments()
Definition: item_func.cc:4777
void add(bool *null_value)
Definition: item_func.cc:4915
udf_func * u_d
Definition: sql_udf.h:85
Udf_args_extension m_args_extension
A struct that holds the extension arguments for each UDF argument.
Definition: sql_udf.h:97
Udf_return_value_extension m_return_value_extension
A struct that holds the extension arguments for return value.
Definition: sql_udf.h:100
udf_handler & operator=(udf_handler &&)=default
Some integer typedefs for easier portability.
unsigned char uchar
Definition: my_inttypes.h:52
long long int longlong
Definition: my_inttypes.h:55
uint64_t table_map
Definition: my_table_map.h:30
std::string str(const mysqlrouter::ConfigGenerator::Options::Endpoint &ep)
Definition: config_generator.cc:1081
void udf_init_globals()
Initialize the UDF global structures.
Definition: sql_udf.cc:200
void udf_hash_for_each_func_t(udf_func *, void *)
Definition: sql_udf.h:151
void udf_hash_rlock(void)
Definition: sql_udf.cc:961
void udf_hash_unlock(void)
Definition: sql_udf.cc:963
void free_udf(udf_func *udf)
Definition: sql_udf.cc:429
bool mysql_drop_function(THD *thd, const LEX_STRING *name)
Drop a user defined function.
Definition: sql_udf.cc:774
void udf_unload_udfs()
Deinitialize the UDF subsystem.
Definition: sql_udf.cc:352
void udf_read_functions_table()
Definition: sql_udf.cc:220
void udf_hash_for_each(udf_hash_for_each_func_t *func, void *arg)
Definition: sql_udf.cc:967
void udf_deinit_globals()
Deinitialize the UDF subsystem.
Definition: sql_udf.cc:379
bool mysql_create_function(THD *thd, udf_func *udf, bool if_not_exists)
Create a user defined function.
Definition: sql_udf.cc:612
ulong udf_hash_size(void)
Definition: sql_udf.cc:965
udf_func * find_udf(const char *name, size_t len=0, bool mark_used=false)
Definition: sql_udf.cc:451
case opt name
Definition: sslopt-case.h:29
Definition: m_ctype.h:423
Definition: mysql_lex_string.h:35
char * str
Definition: mysql_lex_string.h:36
Definition: udf_registration_types.h:48
Information about the result of a user defined function.
Definition: udf_registration_types.h:66
Definition: sql_udf.h:64
Udf_args_extension()
Definition: sql_udf.h:65
const CHARSET_INFO ** charset_info
Definition: sql_udf.h:66
Definition: sql_udf.h:75
const CHARSET_INFO * charset_info
Definition: sql_udf.h:79
Udf_return_value_extension(const CHARSET_INFO *charset_info=nullptr, Item_result result_type=INVALID_RESULT)
Definition: sql_udf.h:76
Item_result result_type
Definition: sql_udf.h:80
Definition: sql_udf.h:44
char * dl
Definition: sql_udf.h:48
ulong usage_count
Definition: sql_udf.h:55
Item_result returns
Definition: sql_udf.h:46
Udf_func_add func_add
Definition: sql_udf.h:54
void * dlhandle
Definition: sql_udf.h:49
Item_udftype type
Definition: sql_udf.h:47
LEX_STRING name
Definition: sql_udf.h:45
Udf_func_any func
Definition: sql_udf.h:50
Udf_func_clear func_clear
Definition: sql_udf.h:53
Udf_func_deinit func_deinit
Definition: sql_udf.h:52
Udf_func_init func_init
Definition: sql_udf.h:51
void(* Udf_func_deinit)(UDF_INIT *)
Definition: udf_registration_types.h:80
Item_result
Type of the user defined function return slot and arguments.
Definition: udf_registration_types.h:39
@ STRING_RESULT
not valid for UDFs
Definition: udf_registration_types.h:41
@ INVALID_RESULT
Definition: udf_registration_types.h:40
bool(* Udf_func_init)(UDF_INIT *, UDF_ARGS *, char *)
Definition: udf_registration_types.h:81
void(* Udf_func_clear)(UDF_INIT *, unsigned char *, unsigned char *)
Definition: udf_registration_types.h:77
void(* Udf_func_add)(UDF_INIT *, UDF_ARGS *, unsigned char *, unsigned char *)
Definition: udf_registration_types.h:78
void(* Udf_func_any)(void)
Definition: udf_registration_types.h:82
Item_udftype
Definition: udf_registration_types.h:75