name : sql_get_diagnostics.h /* Copyright (c) 2011, 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 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ #ifndef SQL_GET_DIAGNOSTICS_H #define SQL_GET_DIAGNOSTICS_H /** Diagnostics information forward reference. */ class Diagnostics_information; /** Sql_cmd_get_diagnostics represents a GET DIAGNOSTICS statement. The GET DIAGNOSTICS statement retrieves exception or completion condition information from a diagnostics area, usually pertaining to the last non-diagnostic SQL statement that was executed. */ class Sql_cmd_get_diagnostics : public Sql_cmd { public: /** Constructor, used to represent a GET DIAGNOSTICS statement. @param info Diagnostics information to be obtained. */ Sql_cmd_get_diagnostics(Diagnostics_information *info) : m_info(info) {} enum_sql_command sql_command_code() const override { return SQLCOM_GET_DIAGNOSTICS; } bool execute(THD *thd) override; private: /** The information to be obtained. */ Diagnostics_information *m_info; }; /** Represents the diagnostics information to be obtained. Diagnostic information is made available through statement information and condition information items. */ class Diagnostics_information : public Sql_alloc { public: /** Which diagnostics area to access. Only CURRENT is supported for now. */ enum Which_area { /** Access the first diagnostics area. */ CURRENT_AREA }; /** Set which diagnostics area to access. */ void set_which_da(Which_area area) { m_area= area; } /** Get which diagnostics area to access. */ Which_area get_which_da(void) const { return m_area; } /** Aggregate diagnostics information. @param thd The current thread. @param da The diagnostics area. @retval false on success. @retval true on error */ virtual bool aggregate(THD *thd, const Diagnostics_area *da) = 0; protected: /** Diagnostics_information objects are allocated in thd->mem_root. Do not rely on the destructor for any cleanup. */ virtual ~Diagnostics_information() { DBUG_ASSERT(false); } /** Evaluate a diagnostics information item in a specific context. @param thd The current thread. @param diag_item The diagnostics information item. @param ctx The context to evaluate the item. @retval false on success. @retval true on error. */ template <typename Diag_item, typename Context> bool evaluate(THD *thd, Diag_item *diag_item, Context ctx) { Item *value; /* Get this item's value. */ if (! (value= diag_item->get_value(thd, ctx))) return true; /* Set variable/parameter value. */ return diag_item->set_value(thd, &value); } private: /** Which diagnostics area to access. */ Which_area m_area; }; /** A diagnostics information item. Used to associate a specific diagnostics information item to a target variable. */ class Diagnostics_information_item : public Sql_alloc { public: /** Set a value for this item. @param thd The current thread. @param value The obtained value. @retval false on success. @retval true on error. */ bool set_value(THD *thd, Item **value); protected: /** Constructor, used to represent a diagnostics information item. @param target A target that gets the value of this item. */ Diagnostics_information_item(Item *target) : m_target(target) {} /** Diagnostics_information_item objects are allocated in thd->mem_root. Do not rely on the destructor for any cleanup. */ virtual ~Diagnostics_information_item() { DBUG_ASSERT(false); } private: /** The target variable that will receive the value of this item. */ Item *m_target; }; /** A statement information item. */ class Statement_information_item : public Diagnostics_information_item { public: /** The name of a statement information item. */ enum Name { NUMBER, ROW_COUNT }; /** Constructor, used to represent a statement information item. @param name The name of this item. @param target A target that gets the value of this item. */ Statement_information_item(Name name, Item *target) : Diagnostics_information_item(target), m_name(name) {} /** Obtain value of this statement information item. */ Item *get_value(THD *thd, const Diagnostics_area *da); private: /** The name of this statement information item. */ Name m_name; }; /** Statement information. @remark Provides information about the execution of a statement. */ class Statement_information : public Diagnostics_information { public: /** Constructor, used to represent the statement information of a GET DIAGNOSTICS statement. @param items List of requested statement information items. */ Statement_information(List<Statement_information_item> *items) : m_items(items) {} /** Obtain statement information in the context of a diagnostics area. */ bool aggregate(THD *thd, const Diagnostics_area *da) override; private: /* List of statement information items. */ List<Statement_information_item> *m_items; }; /** A condition information item. */ class Condition_information_item : public Diagnostics_information_item { public: /** The name of a condition information item. */ enum Name { CLASS_ORIGIN, SUBCLASS_ORIGIN, CONSTRAINT_CATALOG, CONSTRAINT_SCHEMA, CONSTRAINT_NAME, CATALOG_NAME, SCHEMA_NAME, TABLE_NAME, COLUMN_NAME, CURSOR_NAME, MESSAGE_TEXT, MYSQL_ERRNO, RETURNED_SQLSTATE }; /** Constructor, used to represent a condition information item. @param name The name of this item. @param target A target that gets the value of this item. */ Condition_information_item(Name name, Item *target) : Diagnostics_information_item(target), m_name(name) {} /** Obtain value of this condition information item. */ Item *get_value(THD *thd, const Sql_condition *cond); private: /** The name of this condition information item. */ Name m_name; /** Create an string item to represent a condition item string. */ Item *make_utf8_string_item(THD *thd, const String *str); }; /** Condition information. @remark Provides information about conditions raised during the execution of a statement. */ class Condition_information : public Diagnostics_information { public: /** Constructor, used to represent the condition information of a GET DIAGNOSTICS statement. @param cond_number_expr Number that identifies the diagnostic condition. @param items List of requested condition information items. */ Condition_information(Item *cond_number_expr, List<Condition_information_item> *items) : m_cond_number_expr(cond_number_expr), m_items(items) {} /** Obtain condition information in the context of a diagnostics area. */ bool aggregate(THD *thd, const Diagnostics_area *da) override; private: /** Number that identifies the diagnostic condition for which information is to be obtained. */ Item *m_cond_number_expr; /** List of condition information items. */ List<Condition_information_item> *m_items; }; #endif