Protocol_local: a helper class to intercept the result of the data written to the network. More...

Inheritance diagram for Protocol_local:

Public Member Functions
	Protocol_local (THD thd, Ed_connection ed_connection)

	~Protocol_local () override

int	read_packet () override
	Read packet from client. More...

int	get_command (COM_DATA com_data, enum_server_command cmd) override
	Reads the command from the protocol and creates a command. More...

ulong	get_client_capabilities () override
	Returns the client capabilities stored on the protocol. More...

bool	has_client_capability (unsigned long client_capability) override
	Checks if the client capabilities include the one specified as parameter. More...

void	end_partial_result_set () override

int	shutdown (bool server_shutdown=false) override
	Thread is being shut down, disconnect and free resources. More...

bool	connection_alive () const override
	Checks if the protocol's connection with the client is still alive. More...

void	start_row () override
	Called between two result set rows. More...

bool	end_row () override
	Add the current row to the result set. More...

void	abort_row () override

uint	get_rw_status () override
	Returns the read/writing status. More...

bool	get_compression () override
	Returns if the protocol is compressed or not. More...

char *	get_compression_algorithm () override
	Returns compression algorithm name. More...

uint	get_compression_level () override
	Returns compression level. More...

bool	start_result_metadata (uint num_cols, uint flags, const CHARSET_INFO *resultcs) override
	Prepares the server for metadata sending. More...

bool	end_result_metadata () override
	Signals the client that the metadata sending is done. More...

bool	send_field_metadata (Send_field field, const CHARSET_INFO charset) override
	Sends field metadata. More...

bool	flush () override
	Used for the classic protocol. More...

bool	send_parameters (List< Item_param > *, bool) override
	Sends the OUT-parameters to the client. More...

bool	store_ps_status (ulong, uint, uint, ulong) override
	Sends prepared statement's id and metadata to the client after prepare. More...

Public Member Functions inherited from Protocol
virtual	~Protocol ()=default

Protocol *	pop_protocol ()
	Remove the reference to the previous protocol and return it. More...

void	push_protocol (Protocol *protocol)
	Set reference to "this" as the previous protocol on the protocol provided as argument. More...

bool	store (int from)

bool	store (uint32 from)

bool	store (longlong from)

bool	store (ulonglong from)

bool	store_tiny (longlong from)

bool	store_short (longlong from)

bool	store_long (longlong from)

bool	store_longlong (longlong from, bool unsigned_flag)

bool	store (const char from, const CHARSET_INFO fromcs)
	Send \0 end terminated string. More...

bool	store (String *str)

bool	store (const LEX_STRING &s, const CHARSET_INFO *cs)

Protected Member Functions
bool	store_null () override
	Add a NULL column to the current row. More...

bool	store_tiny (longlong from, uint32) override
	Store a tiny int as is (1 byte) in a result set column. More...

bool	store_short (longlong from, uint32) override
	Store a short as is (2 bytes, host order) in a result set column. More...

bool	store_long (longlong from, uint32) override
	Store a "long" as is (4 bytes, host order) in a result set column. More...

bool	store_longlong (longlong from, bool unsigned_flag, uint32) override
	Store a "longlong" as is (8 bytes, host order) in a result set column. More...

bool	store_decimal (const my_decimal *, uint, uint) override
	Store a decimal in string format in a result set column. More...

bool	store_string (const char from, size_t length, const CHARSET_INFO cs) override
	Convert to cs_results and store a string. More...

bool	store_datetime (const MYSQL_TIME &time, uint precision) override

bool	store_date (const MYSQL_TIME &time) override
	Store MYSQL_TIME (in binary format) More...

bool	store_time (const MYSQL_TIME &time, uint precision) override
	Store MYSQL_TIME (in binary format) More...

bool	store_float (float value, uint32 decimals, uint32 zerofill) override

bool	store_double (double value, uint32 decimals, uint32 zerofill) override

bool	store_field (const Field *field) override

enum enum_protocol_type	type () const override

enum enum_vio_type	connection_type () const override

bool	send_ok (uint server_status, uint statement_warn_count, ulonglong affected_rows, ulonglong last_insert_id, const char *message) override
	Called for statements that don't have a result set, at statement end. More...

bool	send_eof (uint server_status, uint statement_warn_count) override
	Called at the end of a result set. More...

bool	send_error (uint sql_errno, const char err_msg, const char sqlstate) override
	Called to send an error to the client at the end of a statement. More...

Private Member Functions
bool	store_string (const char str, size_t length, const CHARSET_INFO src_cs, const CHARSET_INFO *dst_cs)
	Store a string value in a result set column, optionally having converted it to character_set_results. More...

bool	store_column (const void *data, size_t length)
	A helper method to add any column to the current row in its binary form. More...

void	opt_add_row_to_rset ()
	A helper function to add the current row to the current result set. More...

Private Attributes
Ed_connection *	m_connection

MEM_ROOT	m_rset_root

List< Ed_row > *	m_rset

size_t	m_column_count

Ed_column *	m_current_row

Ed_column *	m_current_column

Ed_row *	m_fields

bool	m_send_metadata

THD *	m_thd

Additional Inherited Members
Public Types inherited from Protocol
enum	enum_protocol_type { PROTOCOL_TEXT = 0 , PROTOCOL_BINARY = 1 , PROTOCOL_LOCAL = 2 , PROTOCOL_ERROR = 3 , PROTOCOL_PLUGIN = 4 }
	Enum used by type() to specify the protocol type. More...

enum	{ SEND_NUM_ROWS = 1 , SEND_DEFAULTS = 2 , SEND_EOF = 4 }
	Flags available to alter the way the messages are sent to the client. More...

using	Type = BaseProtocol::Type

Static Public Member Functions inherited from Protocol
static Type	get_default ()

static Type	get_by_name (const std::string &name)
	Returns type of the protocol by its name. More...

static uint16_t	get_default_port (Type type)
	Returns default port for the selected protocol. More...

Detailed Description

Protocol_local: a helper class to intercept the result of the data written to the network.

At the start of every result set, start_result_metadata allocates m_rset to prepare for the results. The metadata is stored on m_current_row which will be transferred to m_fields in end_result_metadata. The memory for the metadata is allocated on m_rset_root.

Then, for every row of the result received, each of the fields is stored in m_current_row. Then the row is moved to m_rset and m_current_row is cleared to receive the next row. The memory for all the results are also stored in m_rset_root.

Finally, at the end of the result set, a new instance of Ed_result_set is created on m_rset_root and the result set (m_rset and m_fields) is moved into this instance. The ownership of MEM_ROOT m_rset_root is also transferred to this instance. So, at the end we have a fresh MEM_ROOT, cleared m_rset and m_fields to accept the next result set.

Constructor & Destructor Documentation

◆ Protocol_local()

Protocol_local::Protocol_local	(	THD *	thd,
		Ed_connection *	ed_connection
	)

◆ ~Protocol_local()

Protocol_local::~Protocol_local ( )

inlineoverride

Member Function Documentation

◆ abort_row()

void Protocol_local::abort_row ( )

inlineoverridevirtual

Implements Protocol.

◆ connection_alive()

bool Protocol_local::connection_alive ( ) const

overridevirtual

Checks if the protocol's connection with the client is still alive.

It should always return true unless the protocol closed the connection.

Return values

true	if the connection is still alive
false	otherwise

Implements Protocol.

◆ connection_type()

enum enum_vio_type Protocol_local::connection_type ( ) const

inlineoverrideprotectedvirtual

Implements Protocol.

◆ end_partial_result_set()

void Protocol_local::end_partial_result_set ( )

overridevirtual

Implements Protocol.

◆ end_result_metadata()

bool Protocol_local::end_result_metadata ( )

overridevirtual

Signals the client that the metadata sending is done.

Clears the server after sending the metadata.

Return values

false	Ok
true	An error occurred

Implements Protocol.

◆ end_row()

bool Protocol_local::end_row ( )

overridevirtual

Add the current row to the result set.

Implements Protocol.

◆ flush()

bool Protocol_local::flush ( )

inlineoverridevirtual

Used for the classic protocol.

Makes the protocol send the messages/data to the client.

Return values

false	The flush was successful.
true	An error occurred.

Implements Protocol.

◆ get_client_capabilities()

ulong Protocol_local::get_client_capabilities ( )

overridevirtual

Returns the client capabilities stored on the protocol.

The available capabilities are defined in mysql_com.h

Implements Protocol.

◆ get_command()

int Protocol_local::get_command	(	COM_DATA *	com_data,
		enum_server_command *	cmd
	)

overridevirtual

Reads the command from the protocol and creates a command.

Parameters

com_data	out parameter
cmd	out parameter

Returns: -1 fatal protocol error 0 ok 1 non-fatal protocol or parsing error

Implements Protocol.

◆ get_compression()

bool Protocol_local::get_compression ( )

overridevirtual

Returns if the protocol is compressed or not.

Return values

false	Not compressed
true	Compressed

Implements Protocol.

◆ get_compression_algorithm()

char * Protocol_local::get_compression_algorithm ( )

overridevirtual

Returns compression algorithm name.

Return values

string	compression method name
NULL	if no compression is enabled

Implements Protocol.

◆ get_compression_level()

uint Protocol_local::get_compression_level ( )

overridevirtual

Returns compression level.

Returns: compression level

Implements Protocol.

◆ get_rw_status()

uint Protocol_local::get_rw_status ( )

overridevirtual

Returns the read/writing status.

Return values

1	Read
2	Write
0	Other(Idle, Killed)

Implements Protocol.

◆ has_client_capability()

bool Protocol_local::has_client_capability ( unsigned long client_capability )

overridevirtual

Checks if the client capabilities include the one specified as parameter.

Return values

true	if it includes the specified capability
false	otherwise

Implements Protocol.

◆ opt_add_row_to_rset()

void Protocol_local::opt_add_row_to_rset ( )

private

A helper function to add the current row to the current result set.

Called in

See also: start_row(), when a new row is started, and in send_eof(), when the result set is finished.

◆ read_packet()

int Protocol_local::read_packet ( )

overridevirtual

Read packet from client.

Return values

-1	fatal error
0	ok
1	non-fatal error

Implements Protocol.

◆ send_eof()

bool Protocol_local::send_eof	(	uint	server_status,
		uint	statement_warn_count
	)

overrideprotectedvirtual

Called at the end of a result set.

Append a complete result set to the list in Ed_connection.

Don't send anything to the client, but instead finish building of the result set at hand.

Implements Protocol.

◆ send_error()

bool Protocol_local::send_error	(	uint	sql_errno,
		const char *	err_msg,
		const char *	sqlstate
	)

overrideprotectedvirtual

Called to send an error to the client at the end of a statement.

Implements Protocol.

◆ send_field_metadata()

bool Protocol_local::send_field_metadata	(	Send_field *	field,
		const CHARSET_INFO *	charset
	)

overridevirtual

Sends field metadata.

Parameters

field	Field metadata to be send to the client
charset	Field's charset: in case it is different than the one used by the connection it will be used to convert the value to the connection's charset

Return values

false	The metadata was successfully sent
true	An error occurred

Implements Protocol.

◆ send_ok()

bool Protocol_local::send_ok	(	uint	server_status,
		uint	statement_warn_count,
		ulonglong	affected_rows,
		ulonglong	last_insert_id,
		const char *	message
	)

overrideprotectedvirtual

Called for statements that don't have a result set, at statement end.

Implements Protocol.

◆ send_parameters()

bool Protocol_local::send_parameters	(	List< Item_param > *	parameters,
		bool	is_sql_prepare
	)

inlineoverridevirtual

Sends the OUT-parameters to the client.

Parameters

parameters	List of PS/SP parameters (both input and output).
is_sql_prepare	Used for the legacy protocol. If we're dealing with sql prepare then text protocol will be used.

Returns: Error status.

Return values

false	Success.
true	Error.

Implements Protocol.

◆ shutdown()

int Protocol_local::shutdown ( bool server_shutdown = false )

overridevirtual

Thread is being shut down, disconnect and free resources.

Parameters

server_shutdown If false then this is normal thread shutdown. If true then the server is shutting down.

Implements Protocol.

◆ start_result_metadata()

bool Protocol_local::start_result_metadata	(	uint	num_cols,
		uint	flags,
		const CHARSET_INFO *	resultcs
	)

overridevirtual

Prepares the server for metadata sending.

Notifies the client that the metadata sending will start.

Parameters

num_cols	Number of columns that will be sent
flags	Flags to alter the metadata sending Can be any of the following: SEND_NUM_ROWS, SEND_DEFAULTS, SEND_EOF
resultcs	Charset to convert to

Return values

false	Ok
true	An error occurred

Implements Protocol.

◆ start_row()

void Protocol_local::start_row ( )

overridevirtual

Called between two result set rows.

Prepare structures to fill result set rows. Unfortunately, we can't return an error here. If memory allocation fails, we'll have to return an error later. And so is done in methods such as

See also: store_column().

Implements Protocol.

◆ store_column()

bool Protocol_local::store_column	(	const void *	data,
		size_t	length
	)

private

A helper method to add any column to the current row in its binary form.

Allocates memory for the data in the result set memory root.

◆ store_date()

bool Protocol_local::store_date ( const MYSQL_TIME & time )

overrideprotectedvirtual

Store MYSQL_TIME (in binary format)

Implements Protocol.

◆ store_datetime()

bool Protocol_local::store_datetime	(	const MYSQL_TIME &	time,
		uint	precision
	)

overrideprotectedvirtual

Implements Protocol.

◆ store_decimal()

bool Protocol_local::store_decimal	(	const my_decimal *	value,
		uint	prec,
		uint	dec
	)

overrideprotectedvirtual

Store a decimal in string format in a result set column.

Implements Protocol.

◆ store_double()

bool Protocol_local::store_double	(	double	value,
		uint32	decimals,
		uint32	zerofill
	)

overrideprotectedvirtual

Implements Protocol.

◆ store_field()

bool Protocol_local::store_field ( const Field * field )

overrideprotectedvirtual

Implements Protocol.

◆ store_float()

bool Protocol_local::store_float	(	float	value,
		uint32	decimals,
		uint32	zerofill
	)

overrideprotectedvirtual

Implements Protocol.

◆ store_long()

bool Protocol_local::store_long	(	longlong	value,
		uint32
	)

overrideprotectedvirtual

Store a "long" as is (4 bytes, host order) in a result set column.

Implements Protocol.

◆ store_longlong()

bool Protocol_local::store_longlong	(	longlong	from,
		bool	unsigned_flag,
		uint32
	)

overrideprotectedvirtual

Store a "longlong" as is (8 bytes, host order) in a result set column.

Implements Protocol.

◆ store_null()

bool Protocol_local::store_null ( )

overrideprotectedvirtual

Add a NULL column to the current row.

Implements Protocol.

◆ store_ps_status()

bool Protocol_local::store_ps_status	(	ulong	stmt_id,
		uint	column_count,
		uint	param_count,
		ulong	cond_count
	)

inlineoverridevirtual

Sends prepared statement's id and metadata to the client after prepare.

Parameters

stmt_id	Statement id.
column_count	Number of columns.
param_count	Number of parameters.
cond_count	Number of conditions raised by the current statement.

Returns: Error status.

Return values

false	The send was successful.
true	An error occurred.

Implements Protocol.

◆ store_short()

bool Protocol_local::store_short	(	longlong	from,
		uint32
	)

overrideprotectedvirtual

Store a short as is (2 bytes, host order) in a result set column.

Implements Protocol.

◆ store_string() [1/2]

bool Protocol_local::store_string	(	const char *	from,
		size_t	length,
		const CHARSET_INFO *	cs
	)

overrideprotectedvirtual

Convert to cs_results and store a string.

Implements Protocol.

◆ store_string() [2/2]

bool Protocol_local::store_string	(	const char *	str,
		size_t	length,
		const CHARSET_INFO *	src_cs,
		const CHARSET_INFO *	dst_cs
	)

private

Store a string value in a result set column, optionally having converted it to character_set_results.

◆ store_time()

bool Protocol_local::store_time	(	const MYSQL_TIME &	time,
		uint	precision
	)

overrideprotectedvirtual

Store MYSQL_TIME (in binary format)

Implements Protocol.

◆ store_tiny()

bool Protocol_local::store_tiny	(	longlong	from,
		uint32
	)

overrideprotectedvirtual

Store a tiny int as is (1 byte) in a result set column.

Implements Protocol.

◆ type()

enum enum_protocol_type Protocol_local::type ( ) const

inlineoverrideprotectedvirtual

Implements Protocol.

Member Data Documentation

◆ m_column_count

size_t Protocol_local::m_column_count

private

◆ m_connection

Ed_connection* Protocol_local::m_connection

private

◆ m_current_column

Ed_column* Protocol_local::m_current_column

private

◆ m_current_row

Ed_column* Protocol_local::m_current_row

private

◆ m_fields

Ed_row* Protocol_local::m_fields

private

◆ m_rset

List<Ed_row>* Protocol_local::m_rset

private

◆ m_rset_root

MEM_ROOT Protocol_local::m_rset_root

private

◆ m_send_metadata

bool Protocol_local::m_send_metadata

private

◆ m_thd

THD* Protocol_local::m_thd

private

The documentation for this class was generated from the following file:

sql/sql_prepare.cc

Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Protocol_local()

◆ ~Protocol_local()

Member Function Documentation

◆ abort_row()

◆ connection_alive()

◆ connection_type()

◆ end_partial_result_set()

◆ end_result_metadata()

◆ end_row()

◆ flush()

◆ get_client_capabilities()

◆ get_command()

◆ get_compression()

◆ get_compression_algorithm()

◆ get_compression_level()

◆ get_rw_status()

◆ has_client_capability()

◆ opt_add_row_to_rset()

◆ read_packet()

◆ send_eof()

◆ send_error()

◆ send_field_metadata()

◆ send_ok()

◆ send_parameters()

◆ shutdown()

◆ start_result_metadata()

◆ start_row()

◆ store_column()

◆ store_date()

◆ store_datetime()

◆ store_decimal()

◆ store_double()

◆ store_field()

◆ store_float()

◆ store_long()

◆ store_longlong()

◆ store_null()

◆ store_ps_status()

◆ store_short()

◆ store_string() [1/2]

◆ store_string() [2/2]

◆ store_time()

◆ store_tiny()

◆ type()

Member Data Documentation

◆ m_column_count

◆ m_connection

◆ m_current_column

◆ m_current_row

◆ m_fields

◆ m_rset

◆ m_rset_root

◆ m_send_metadata

◆ m_thd