1 /* Copyright (c) 2015, 2021, Oracle and/or its affiliates.
2 
3   This program is free software; you can redistribute it and/or modify
4   it under the terms of the GNU General Public License, version 2.0,
5   as published by the Free Software Foundation.
6 
7   This program is also distributed with certain software (including
8   but not limited to OpenSSL) that is licensed under separate terms,
9   as designated in a particular file or component or in included license
10   documentation.  The authors of MySQL hereby grant you an additional
11   permission to link the program and your derivative works with the
12   separately licensed software that they have included with MySQL.
13 
14   This program is distributed in the hope that it will be useful,
15   but WITHOUT ANY WARRANTY; without even the implied warranty of
16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License, version 2.0, for more details.
18 
19   You should have received a copy of the GNU General Public License
20   along with this program; if not, write to the Free Software
21   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
22 
23 #ifndef TABLE_STATUS_BY_ACCOUNT_H
24 #define TABLE_STATUS_BY_ACCOUNT_H
25 
26 /**
27   @file storage/perfschema/table_status_by_account.h
28   Table STATUS_BY_ACCOUNT (declarations).
29 */
30 
31 #include "pfs_column_types.h"
32 #include "pfs_engine_table.h"
33 #include "pfs_instr_class.h"
34 #include "pfs_instr.h"
35 #include "pfs_account.h"
36 #include "pfs_account.h"
37 #include "pfs_host.h"
38 #include "table_helper.h"
39 #include "pfs_variable.h"
40 #include "pfs_buffer_container.h"
41 
42 /**
43   @addtogroup Performance_schema_tables
44   @{
45 */
46 
47 /**
48   A row of table
49   PERFORMANCE_SCHEMA.STATUS_BY_ACCOUNT.
50 */
51 struct row_status_by_account
52 {
53   /** Column USER, HOST. */
54   PFS_account_row m_account;
55   /** Column VARIABLE_NAME. */
56   PFS_variable_name_row m_variable_name;
57   /** Column VARIABLE_VALUE. */
58   PFS_variable_value_row m_variable_value;
59 };
60 
61 /**
62   Position of a cursor on
63   PERFORMANCE_SCHEMA.STATUS_BY_ACCOUNT.
64   Index 1 on account (0 based)
65   Index 2 on status variable (0 based)
66 */
67 struct pos_status_by_account
68 : public PFS_double_index
69 {
pos_status_by_accountpos_status_by_account70   pos_status_by_account()
71     : PFS_double_index(0, 0)
72   {}
73 
resetpos_status_by_account74   inline void reset(void)
75   {
76     m_index_1= 0;
77     m_index_2= 0;
78   }
79 
has_more_accountpos_status_by_account80   inline bool has_more_account(void)
81   { return (m_index_1 < global_account_container.get_row_count()); }
82 
next_accountpos_status_by_account83   inline void next_account(void)
84   {
85     m_index_1++;
86     m_index_2= 0;
87   }
88 };
89 
90 /**
91   Store and retrieve table state information for queries that reinstantiate
92   the table object.
93 */
94 class table_status_by_account_context : public PFS_table_context
95 {
96 public:
table_status_by_account_context(ulonglong current_version,bool restore)97   table_status_by_account_context(ulonglong current_version, bool restore) :
98     PFS_table_context(current_version, global_account_container.get_row_count(), restore, THR_PFS_SBH) { }
99 };
100 
101 /** Table PERFORMANCE_SCHEMA.STATUS_BY_ACCOUNT. */
102 class table_status_by_account : public PFS_engine_table
103 {
104   typedef pos_status_by_account pos_t;
105 
106 public:
107   /** Table share */
108   static PFS_engine_table_share m_share;
109   static PFS_engine_table* create();
110   static int delete_all_rows();
111   static ha_rows get_row_count();
112 
113   virtual int rnd_init(bool scan);
114   virtual int rnd_next();
115   virtual int rnd_pos(const void *pos);
116   virtual void reset_position(void);
117 
118 protected:
119   virtual int read_row_values(TABLE *table,
120                               unsigned char *buf,
121                               Field **fields,
122                               bool read_all);
123   table_status_by_account();
124 
125 public:
~table_status_by_account()126   ~table_status_by_account()
127   {}
128 
129 protected:
130   int materialize(PFS_thread *pfs_thread);
131   void make_row(PFS_account *pfs_account, const Status_variable *status_var);
132 
133 private:
134   /** Table share lock. */
135   static THR_LOCK m_table_lock;
136   /** Fields definition. */
137   static TABLE_FIELD_DEF m_field_def;
138 
139   /** Status variable cache for one account. */
140   PFS_status_variable_cache m_status_cache;
141 
142   /** Current row. */
143   row_status_by_account m_row;
144   /** True if the current row exists. */
145   bool m_row_exists;
146   /** Current position. */
147   pos_t m_pos;
148   /** Next position. */
149   pos_t m_next_pos;
150 
151   /** Table context with global status array version and map of materialized threads. */
152   table_status_by_account_context *m_context;
153 };
154 
155 /** @} */
156 #endif
157