/* Copyright (c) 2016, 2019, 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, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include "sql/sql_show_status.h" #include #include "lex_string.h" #include "m_string.h" // STRING_WITH_LEN #include "my_sqlcommand.h" #include "sql/item_cmpfunc.h" // Item_func_like #include "sql/mem_root_array.h" #include "sql/parse_tree_items.h" // PTI_simple_ident_ident #include "sql/parse_tree_nodes.h" // PT_select_item_list #include "sql/sql_class.h" // THD #include "sql/sql_lex.h" // Query_options #include "sql/strfunc.h" #include "sql_string.h" /** Build a replacement query for SHOW STATUS. When the parser accepts the following syntax: SHOW GLOBAL STATUS the parsed tree built for this query is in fact: SELECT * FROM (SELECT VARIABLE_NAME as Variable_name, VARIABLE_VALUE as Value FROM performance_schema.global_status) global_status Likewise, the query: SHOW GLOBAL STATUS LIKE "" is built as: SELECT * FROM (SELECT VARIABLE_NAME as Variable_name, VARIABLE_VALUE as Value FROM performance_schema.global_status) global_status WHERE Variable_name LIKE "" Likewise, the query: SHOW GLOBAL STATUS where @ is built as: SELECT * FROM (SELECT VARIABLE_NAME as Variable_name, VARIABLE_VALUE as Value FROM performance_schema.global_status) global_status WHERE @ */ static SELECT_LEX *build_query(const POS &pos, THD *thd, enum_sql_command command, const LEX_CSTRING &table_name, const String *wild, Item *where_cond) { /* MAINTAINER: This code builds a parsed tree for a query. Write the query to build in SQL first, then see turn_parser_debug_on() in sql_yacc.yy to understand which grammar actions are needed to build a parsed tree for this SQL query. */ static const LEX_CSTRING col_name = {STRING_WITH_LEN("VARIABLE_NAME")}; static const LEX_CSTRING as_name = {STRING_WITH_LEN("Variable_name")}; static const LEX_CSTRING col_value = {STRING_WITH_LEN("VARIABLE_VALUE")}; static const LEX_CSTRING as_value = {STRING_WITH_LEN("Value")}; static const LEX_CSTRING pfs = {STRING_WITH_LEN("performance_schema")}; static const LEX_CSTRING star = {STRING_WITH_LEN("*")}; static const Query_options options = { 0 /* query_spec_options */ }; /* ... VARIABLE_NAME ... */ PTI_simple_ident_ident *ident_name; ident_name = new (thd->mem_root) PTI_simple_ident_ident(pos, col_name); if (ident_name == NULL) return NULL; /* ... VARIABLE_NAME as Variable_name ... */ PTI_expr_with_alias *expr_name; expr_name = new (thd->mem_root) PTI_expr_with_alias(pos, ident_name, pos.cpp, as_name); if (expr_name == NULL) return NULL; /* ... VARIABLE_VALUE ... */ PTI_simple_ident_ident *ident_value; ident_value = new (thd->mem_root) PTI_simple_ident_ident(pos, col_value); if (ident_value == NULL) return NULL; /* ... VARIABLE_VALUE as Value ... */ PTI_expr_with_alias *expr_value; expr_value = new (thd->mem_root) PTI_expr_with_alias(pos, ident_value, pos.cpp, as_value); if (expr_value == NULL) return NULL; /* ... VARIABLE_NAME as Variable_name, VARIABLE_VALUE as Value ... */ PT_select_item_list *item_list; item_list = new (thd->mem_root) PT_select_item_list(); if (item_list == NULL) return NULL; item_list->push_back(expr_name); item_list->push_back(expr_value); /* make_table_list() might alter the database and table name strings. Create copies and leave the original values unaltered. */ /* ... performance_schema ... */ LEX_CSTRING tmp_db_name; if (lex_string_strmake(thd->mem_root, &tmp_db_name, pfs.str, pfs.length)) return NULL; /* ... ... */ LEX_CSTRING tmp_table_name; if (lex_string_strmake(thd->mem_root, &tmp_table_name, table_name.str, table_name.length)) return NULL; /* ... performance_schema. ... */ Table_ident *table_ident; table_ident = new (thd->mem_root) Table_ident(tmp_db_name, tmp_table_name); if (table_ident == NULL) return NULL; /* ... FROM performance_schema. ... */ PT_table_factor_table_ident *table_factor; table_factor = new (thd->mem_root) PT_table_factor_table_ident(table_ident, NULL, NULL_CSTR, NULL); if (table_factor == NULL) return NULL; Mem_root_array_YY table_reference_list; table_reference_list.init(thd->mem_root); if (table_reference_list.push_back(table_factor)) return NULL; /* Form subquery */ /* SELECT VARIABLE_NAME as Variable_name, VARIABLE_VALUE as Value FROM * performance_schema. */ PT_query_primary *query_specification; query_specification = new (thd->mem_root) PT_query_specification(options, item_list, table_reference_list, // from NULL); // where if (query_specification == NULL) return NULL; PT_query_expression_body_primary *query_expression_body_primary; query_expression_body_primary = new (thd->mem_root) PT_query_expression_body_primary(query_specification); if (query_expression_body_primary == NULL) return NULL; PT_query_expression *query_expression; query_expression = new (thd->mem_root) PT_query_expression(query_expression_body_primary); if (query_expression == NULL) return NULL; PT_subquery *sub_query; sub_query = new (thd->mem_root) PT_subquery(pos, query_expression); if (sub_query == NULL) return NULL; Create_col_name_list column_names; column_names.init(thd->mem_root); PT_derived_table *derived_table; derived_table = new (thd->mem_root) PT_derived_table(false, sub_query, table_name, &column_names); if (derived_table == NULL) return NULL; Mem_root_array_YY table_reference_list1; table_reference_list1.init(thd->mem_root); if (table_reference_list1.push_back(derived_table)) return NULL; /* SELECT * ... */ PTI_simple_ident_ident *ident_star; ident_star = new (thd->mem_root) PTI_simple_ident_ident(pos, star); if (ident_star == NULL) return NULL; PT_select_item_list *item_list1; item_list1 = new (thd->mem_root) PT_select_item_list(); if (item_list1 == NULL) return NULL; item_list1->push_back(ident_star); /* Process where clause */ Item *where_clause = NULL; if (wild != NULL) { /* ... Variable_name ... */ PTI_simple_ident_ident *ident_name_where; ident_name_where = new (thd->mem_root) PTI_simple_ident_ident(pos, as_name); if (ident_name_where == NULL) return NULL; /* ... ... */ LEX_STRING *lex_string; lex_string = static_cast(thd->alloc(sizeof(LEX_STRING))); if (lex_string == NULL) return NULL; lex_string->length = wild->length(); lex_string->str = thd->strmake(wild->ptr(), wild->length()); if (lex_string->str == NULL) return NULL; PTI_text_literal_text_string *wild_string; wild_string = new (thd->mem_root) PTI_text_literal_text_string( pos, false, *lex_string); // TODO WL#6629 check is_7bit if (wild_string == NULL) return NULL; /* ... Variable_name LIKE ... */ Item_func_like *func_like; func_like = new (thd->mem_root) Item_func_like(pos, ident_name_where, wild_string, NULL); if (func_like == NULL) return NULL; /* ... WHERE Variable_name LIKE ... */ where_clause = new (thd->mem_root) PTI_where(pos, func_like); if (where_clause == NULL) return NULL; } else { where_clause = where_cond; } /* SELECT * FROM (SELECT ...) derived_table [ WHERE Variable_name LIKE * ] */ /* SELECT * FROM (SELECT ...) derived_table [ WHERE ] */ PT_query_specification *query_specification2; query_specification2 = new (thd->mem_root) PT_query_specification(options, item_list1, table_reference_list1, // from where_clause); // where if (query_specification2 == NULL) return NULL; PT_query_expression_body_primary *query_expression_body_primary2; query_expression_body_primary2 = new (thd->mem_root) PT_query_expression_body_primary(query_specification2); if (query_expression_body_primary2 == NULL) return NULL; PT_query_expression *query_expression2; query_expression2 = new (thd->mem_root) PT_query_expression(query_expression_body_primary2); if (query_expression2 == NULL) return NULL; LEX *lex = thd->lex; SELECT_LEX *current_select = lex->current_select(); Parse_context pc(thd, current_select); if (thd->is_error()) return NULL; lex->sql_command = SQLCOM_SELECT; if (query_expression2->contextualize(&pc)) return NULL; /* contextualize sets to COM_SELECT */ lex->sql_command = command; return current_select; } SELECT_LEX *build_show_session_status(const POS &pos, THD *thd, const String *wild, Item *where_cond) { static const LEX_CSTRING table_name = {STRING_WITH_LEN("session_status")}; return build_query(pos, thd, SQLCOM_SHOW_STATUS, table_name, wild, where_cond); } SELECT_LEX *build_show_global_status(const POS &pos, THD *thd, const String *wild, Item *where_cond) { static const LEX_CSTRING table_name = {STRING_WITH_LEN("global_status")}; return build_query(pos, thd, SQLCOM_SHOW_STATUS, table_name, wild, where_cond); } SELECT_LEX *build_show_session_variables(const POS &pos, THD *thd, const String *wild, Item *where_cond) { static const LEX_CSTRING table_name = {STRING_WITH_LEN("session_variables")}; return build_query(pos, thd, SQLCOM_SHOW_VARIABLES, table_name, wild, where_cond); } SELECT_LEX *build_show_global_variables(const POS &pos, THD *thd, const String *wild, Item *where_cond) { static const LEX_CSTRING table_name = {STRING_WITH_LEN("global_variables")}; return build_query(pos, thd, SQLCOM_SHOW_VARIABLES, table_name, wild, where_cond); }