MySQL 8.0.29
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, 2022, 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 also distributed 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 included with MySQL.
16
17 This program is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 GNU General Public License, version 2.0, for more details.
21
22 You should have received a copy of the GNU General Public License
23 along with this program; if not, write to the Free Software
24 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
25
26/* This file defines structures needed by udf functions */
27
28#include <stddef.h>
29#include <sys/types.h>
30
31#include "lex_string.h"
32#include "my_inttypes.h"
33#include "my_table_map.h"
35
36class Item;
38class String;
39class THD;
40class my_decimal;
41struct CHARSET_INFO;
42
43struct udf_func {
47 char *dl;
48 void *dlhandle;
55};
56
57/*
58 A structure of extension attributes for a UDF argument.
59 The extension pointer of UDF_ARGS may point to the object of this
60 structure. There are udf_extension component services to set and get
61 the extension attributes of argument.
62*/
66};
67
68/*
69 A structure of extension attributes for return value of UDF.
70 The extension pointer of UDF_INIT may point to the object of this
71 structure. There are udf_extension component services to set and get
72 the extension attributes of return value.
73*/
80};
81
83 protected:
85 String *buffers{nullptr};
88 char *num_buffer{nullptr};
91 /// True when handler has been initialized and use count incremented
92 bool m_initialized{false};
93 /// True when init function has been called
94 bool m_init_func_called{false};
96 Udf_args_extension m_args_extension; /**< A struct that holds the extension
97 arguments for each UDF argument */
99 m_return_value_extension; /**< A struct that holds the extension arguments
100 for return value */
101 public:
103 bool m_original{true};
104
105 udf_handler(udf_func *udf_arg);
106 udf_handler(const udf_handler &) = default;
108 udf_handler &operator=(const udf_handler &) = default;
110 // Clean up string buffers
111 void clean_buffers();
112 void free_handler();
113
114 bool is_initialized() const { return m_initialized; }
115
116 const char *name() const { return u_d ? u_d->name.str : "?"; }
118 return (Item_result)(u_d ? (u_d->returns) : STRING_RESULT);
119 }
120 bool fix_fields(THD *thd, Item_result_field *item, uint arg_count,
121 Item **args);
122 void cleanup();
123 bool call_init_func();
124 double val_real(bool *null_value);
125 longlong val_int(bool *null_value);
126 my_decimal *val_decimal(bool *null_value, my_decimal *dec_buf);
127 String *val_str(String *str, String *save_str);
128 void clear();
129 void add(bool *null_value);
130
131 private:
132 bool get_arguments();
133 String *result_string(const char *res, size_t res_length, String *str,
134 String *save_str);
135 void get_string(uint index);
136 bool get_and_convert_string(uint index);
137};
138
139void udf_init_globals();
141void udf_unload_udfs();
142void udf_deinit_globals();
143udf_func *find_udf(const char *name, size_t len = 0, bool mark_used = false);
144void free_udf(udf_func *udf);
145bool mysql_create_function(THD *thd, udf_func *udf, bool if_not_exists);
146bool mysql_drop_function(THD *thd, const LEX_STRING *name);
147ulong udf_hash_size(void);
148void udf_hash_rlock(void);
149void udf_hash_unlock(void);
150typedef void udf_hash_for_each_func_t(udf_func *, void *);
151void udf_hash_for_each(udf_hash_for_each_func_t *func, void *arg);
152#endif /* SQL_UDF_INCLUDED */
Item with result field.
Definition: item.h:5503
Base class that is used to represent any kind of expression in a relational query.
Definition: item.h:802
Using this class is fraught with peril, and you need to be very careful when doing so.
Definition: sql_string.h:166
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_class.h:945
my_decimal class limits 'decimal_t' type to what we need in MySQL.
Definition: my_decimal.h:93
Definition: sql_udf.h:82
bool m_init_func_called
True when init function has been called.
Definition: sql_udf.h:94
bool get_and_convert_string(uint index)
Get the details of the input String argument.
Definition: item_func.cc:4819
Item_result result_type() const
Definition: sql_udf.h:117
bool call_init_func()
Definition: item_func.cc:4562
const char * name() const
Definition: sql_udf.h:116
table_map used_tables_cache
Definition: sql_udf.h:102
my_decimal * val_decimal(bool *null_value, my_decimal *dec_buf)
Definition: item_func.cc:4726
udf_handler(udf_handler &&)=default
UDF_INIT initid
Definition: sql_udf.h:87
longlong val_int(bool *null_value)
Definition: item_func.cc:4670
bool m_initialized
True when handler has been initialized and use count incremented.
Definition: sql_udf.h:92
uchar is_null
Definition: sql_udf.h:90
void get_string(uint index)
Get the details of the input String arguments.
Definition: item_func.cc:4799
udf_handler & operator=(const udf_handler &)=default
bool is_initialized() const
Definition: sql_udf.h:114
char * num_buffer
Definition: sql_udf.h:88
bool m_original
Definition: sql_udf.h:103
bool fix_fields(THD *thd, Item_result_field *item, uint arg_count, Item **args)
Definition: item_func.cc:4420
Item ** args
Definition: sql_udf.h:95
void cleanup()
Definition: item_func.cc:4374
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:4779
UDF_ARGS f_args
Definition: sql_udf.h:86
uchar error
Definition: sql_udf.h:89
void clear()
Definition: item_func.cc:4748
String * val_str(String *str, String *save_str)
Definition: item_func.cc:4692
double val_real(bool *null_value)
Definition: item_func.cc:4653
void free_handler()
Definition: item_func.cc:4402
String * buffers
Definition: sql_udf.h:85
udf_handler(udf_func *udf_arg)
Definition: item_func.cc:4369
void clean_buffers()
Definition: item_func.cc:4395
udf_handler(const udf_handler &)=default
bool get_arguments()
Definition: item_func.cc:4617
void add(bool *null_value)
Definition: item_func.cc:4755
udf_func * u_d
Definition: sql_udf.h:84
Udf_args_extension m_args_extension
A struct that holds the extension arguments for each UDF argument.
Definition: sql_udf.h:96
Udf_return_value_extension m_return_value_extension
A struct that holds the extension arguments for return value.
Definition: sql_udf.h:99
udf_handler & operator=(udf_handler &&)=default
Fido Client Authentication nullptr
Definition: fido_client_plugin.cc:221
Some integer typedefs for easier portability.
unsigned char uchar
Definition: my_inttypes.h:51
long long int longlong
Definition: my_inttypes.h:54
uint64_t table_map
Definition: my_table_map.h:29
std::string str(const mysqlrouter::ConfigGenerator::Options::Endpoint &ep)
Definition: config_generator.cc:1055
void udf_init_globals()
Initialize the UDF global structures.
Definition: sql_udf.cc:196
void udf_hash_for_each_func_t(udf_func *, void *)
Definition: sql_udf.h:150
void udf_hash_rlock(void)
Definition: sql_udf.cc:957
void udf_hash_unlock(void)
Definition: sql_udf.cc:959
void free_udf(udf_func *udf)
Definition: sql_udf.cc:425
bool mysql_drop_function(THD *thd, const LEX_STRING *name)
Drop a user defined function.
Definition: sql_udf.cc:770
void udf_unload_udfs()
Deintialize the UDF subsystem.
Definition: sql_udf.cc:348
void udf_read_functions_table()
Definition: sql_udf.cc:216
void udf_hash_for_each(udf_hash_for_each_func_t *func, void *arg)
Definition: sql_udf.cc:963
void udf_deinit_globals()
Deintialize the UDF subsystem.
Definition: sql_udf.cc:375
bool mysql_create_function(THD *thd, udf_func *udf, bool if_not_exists)
Create a user defined function.
Definition: sql_udf.cc:608
ulong udf_hash_size(void)
Definition: sql_udf.cc:961
udf_func * find_udf(const char *name, size_t len=0, bool mark_used=false)
Definition: sql_udf.cc:447
case opt name
Definition: sslopt-case.h:32
Definition: m_ctype.h:354
Definition: mysql_lex_string.h:34
char * str
Definition: mysql_lex_string.h:35
Definition: udf_registration_types.h:47
Information about the result of a user defined function.
Definition: udf_registration_types.h:65
Definition: sql_udf.h:63
Udf_args_extension()
Definition: sql_udf.h:64
const CHARSET_INFO ** charset_info
Definition: sql_udf.h:65
Definition: sql_udf.h:74
const CHARSET_INFO * charset_info
Definition: sql_udf.h:78
Udf_return_value_extension(const CHARSET_INFO *charset_info=nullptr, Item_result result_type=INVALID_RESULT)
Definition: sql_udf.h:75
Item_result result_type
Definition: sql_udf.h:79
Definition: sql_udf.h:43
char * dl
Definition: sql_udf.h:47
ulong usage_count
Definition: sql_udf.h:54
Item_result returns
Definition: sql_udf.h:45
Udf_func_add func_add
Definition: sql_udf.h:53
void * dlhandle
Definition: sql_udf.h:48
Item_udftype type
Definition: sql_udf.h:46
LEX_STRING name
Definition: sql_udf.h:44
Udf_func_any func
Definition: sql_udf.h:49
Udf_func_clear func_clear
Definition: sql_udf.h:52
Udf_func_deinit func_deinit
Definition: sql_udf.h:51
Udf_func_init func_init
Definition: sql_udf.h:50
unsigned int uint
Definition: uca-dump.cc:29
void(* Udf_func_deinit)(UDF_INIT *)
Definition: udf_registration_types.h:79
Item_result
Type of the user defined function return slot and arguments.
Definition: udf_registration_types.h:38
@ STRING_RESULT
not valid for UDFs
Definition: udf_registration_types.h:40
@ INVALID_RESULT
Definition: udf_registration_types.h:39
bool(* Udf_func_init)(UDF_INIT *, UDF_ARGS *, char *)
Definition: udf_registration_types.h:80
void(* Udf_func_clear)(UDF_INIT *, unsigned char *, unsigned char *)
Definition: udf_registration_types.h:76
void(* Udf_func_add)(UDF_INIT *, UDF_ARGS *, unsigned char *, unsigned char *)
Definition: udf_registration_types.h:77
void(* Udf_func_any)(void)
Definition: udf_registration_types.h:81
Item_udftype
Definition: udf_registration_types.h:74