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/* 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