#include <sp_head.h>

Public Types
enum	{ HAS_RETURN = 1, MULTI_RESULTS = 8, CONTAINS_DYNAMIC_SQL = 16, IS_INVOKED = 32, HAS_SET_AUTOCOMMIT_STMT = 64, HAS_COMMIT_OR_ROLLBACK = 128, LOG_SLOW_STATEMENTS = 256, LOG_GENERAL_LOG = 512, HAS_SQLCOM_RESET = 1024, HAS_SQLCOM_FLUSH = 2048, MODIFIES_DATA = 4096 }
Public Member Functions
bool	is_invoked () const
	Is this routine being executed?
ulong	sp_cache_version () const
void	set_sp_cache_version (ulong sp_cache_version)
	Set the value of the SP cache version.
Stored_program_creation_ctx *	get_creation_ctx ()
void	set_creation_ctx (Stored_program_creation_ctx *creation_ctx)
void	set_body_start (THD thd, const char begin_ptr)
	Set the body-definition start position.
void	set_body_end (THD *thd)
	Set the statement-definition (body-definition) end position.
bool	execute_trigger (THD thd, const LEX_STRING db_name, const LEX_STRING table_name, GRANT_INFO grant_info)
bool	execute_function (THD thd, Item args, uint argcount, Field return_fld)
bool	execute_procedure (THD thd, List< Item > args)
bool	show_create_routine (THD *thd, enum_sp_type type)
bool	add_instr (THD thd, sp_instr instr)
bool	modifies_data () const
uint	instructions ()
sp_instr *	last_instruction ()
bool	reset_lex (THD *thd)
bool	restore_lex (THD *thd)
char *	name (uint *lenp=0) const
char *	create_string (THD thd, ulong lenp)
Field *	create_result_field (uint field_max_length, const char field_name, TABLE table)
void	set_info (longlong created, longlong modified, st_sp_chistics *chistics, sql_mode_t sql_mode)
void	set_definer (const char *definer, uint definerlen)
void	set_definer (const LEX_STRING user_name, const LEX_STRING host_name)
void	optimize ()
void	add_mark_lead (uint ip, List< sp_instr > *leads)
sp_instr *	get_instr (uint i)
bool	add_used_tables_to_table_list (THD thd, TABLE_LIST *query_tables_last_ptr, TABLE_LIST belong_to_view)
bool	is_not_allowed_in_function (const char *where)
bool	show_routine_code (THD *thd)
void	propagate_attributes (Query_tables_list *prelocking_ctx)
sp_pcontext *	get_root_parsing_context () const
MEM_ROOT *	get_persistent_mem_root () const
MEM_ROOT *	get_current_mem_root () const
bool	check_show_access (THD thd, bool full_access)
bool	set_security_ctx (THD thd, Security_context *save_ctx)
Static Public Member Functions
static void *	operator new (size_t size) throw ()
static void	operator delete (void *ptr, size_t size) throw ()
Public Attributes
enum_sp_type	m_type
	Stored program type.
uint	m_flags
	Stored program flags.
Create_field	m_return_field_def
sp_parser_data	m_parser_data
	Attributes used during the parsing stage only.
st_sp_chistics *	m_chistics
	Stored program characteristics.
sql_mode_t	m_sql_mode
LEX_STRING	m_qname
	Fully qualified name (<db name>="">.<sp name>="">).
bool	m_explicit_name
	Prepend the db name? */.
LEX_STRING	m_db
LEX_STRING	m_name
LEX_STRING	m_params
LEX_STRING	m_body
LEX_STRING	m_body_utf8
LEX_STRING	m_defstr
LEX_STRING	m_definer_user
LEX_STRING	m_definer_host
longlong	m_created
longlong	m_modified
ulong	m_recursion_level
	Recursion level of the current SP instance. The levels are numbered from 0.
sp_head *	m_next_cached_sp
sp_head *	m_first_instance
	Pointer to the first element of the above list.
sp_head *	m_first_free_instance
sp_head *	m_last_cached_sp
HASH	m_sroutines
Security_context	m_security_ctx
SQL_I_List< SQL_I_List < Item_trigger_field > >	m_list_of_trig_fields_item_lists
SQL_I_List< Item_trigger_field >	m_cur_instr_trig_field_items
st_trg_chistics	m_trg_chistics
	Trigger characteristics.
class Table_triggers_list *	m_trg_list
	The Table_triggers_list instance, where this trigger belongs to.
Friends
sp_head *	sp_start_parsing (THD , enum_sp_type, sp_name )

Detailed Description

sp_head represents one instance of a stored program. It might be of any type (stored procedure, function, trigger, event).

Member Enumeration Documentation

anonymous enum

Possible values of m_flags

Enumerator:

MODIFIES_DATA

Marks routines that directly (i.e. not by calling other routines) change tables. Note that this flag is set automatically based on type of statements used in the stored routine and is different from routine characteristic provided by user in a form of CONTAINS SQL, READS SQL DATA, MODIFIES SQL DATA clauses. The latter are accepted by parser but pretty much ignored after that. We don't rely on them: a) for compatibility reasons. b) because in CONTAINS SQL case they don't provide enough information anyway.

Member Function Documentation

bool sp_head::add_instr	(	THD *	thd,
		sp_instr *	instr
	)

Add instruction to SP.

Parameters:

thd	Thread context.
instr	Instruction.

Returns:: Error status.

void sp_head::add_mark_lead	(	uint	ip,
		List< sp_instr > *	leads
	)

Helper used during flow analysis during code optimization. See the implementation of opt_mark().

Parameters:

ip	the instruction to add to the leads list
leads	the list of remaining paths to explore in the graph that represents the code, during flow analysis.

bool sp_head::add_used_tables_to_table_list	(	THD *	thd,
		TABLE_LIST ***	query_tables_last_ptr,
		TABLE_LIST *	belong_to_view
	)

Add tables used by routine to the table list.

Converts multi-set of tables used by this routine to table list and adds this list to the end of table list specified by 'query_tables_last_ptr'.

Elements of list will be allocated in PS memroot, so this list will be persistent between PS executions.

Parameters:

[in]	thd	Thread context
[in,out]	query_tables_last_ptr	Pointer to the next_global member of last element of the list where tables will be added (or to its root).
[in]	belong_to_view	Uppermost view which uses this routine, NULL if none.

Return values:

true	if some elements were added
false	otherwise.

bool sp_head::check_show_access	(	THD *	thd,
		bool *	full_access
	)

Check if a user has access right to a SP.

Parameters:

	thd	Thread context.
[out]	full_access	Set to 1 if the user has SELECT to the 'mysql.proc' table or is the owner of the stored program.

Returns:: Error status.

Field * sp_head::create_result_field	(	uint	field_max_length,
		const char *	field_name,
		TABLE *	table
	)

Create Field-object corresponding to the RETURN field of a stored function. This operation makes sense for stored functions only.

Parameters:

field_max_length	the max length (in the sense of Item classes).
field_name	the field name (item name).
table	the field's table.

Returns:: newly created and initialized Field-instance, or NULL in case of error.

bool sp_head::execute_function	(	THD *	thd,
		Item **	args,
		uint	argcount,
		Field *	return_fld
	)

Execute a function.

evaluate parameters
changes security context for SUID routines
switch to new memroot
call sp_head::execute
restore old memroot
evaluate the return value
restores security context

Parameters:

thd	Thread context.
argp	Passed arguments (these are items from containing statement?)
argcount	Number of passed arguments. We need to check if this is correct.
return_value_fld	Save result here.

Todo:: We should create sp_rcontext once per command and reuse it on subsequent executions of a function/trigger.

Todo:: In future we should associate call arena/mem_root with sp_rcontext and allocate all these objects (and sp_rcontext itself) on it directly rather than juggle with arenas.

Returns:: Error status.

bool sp_head::execute_procedure	(	THD *	thd,
		List< Item > *	args
	)

Execute a procedure.

The function does the following steps:

Set all parameters
changes security context for SUID routines
call sp_head::execute
copy back values of INOUT and OUT parameters
restores security context

Parameters:

thd	Thread context.
args	List of values passed as arguments.

Returns:: Error status.

bool sp_head::execute_trigger	(	THD *	thd,
		const LEX_STRING *	db_name,
		const LEX_STRING *	table_name,
		GRANT_INFO *	grant_info
	)

Execute trigger stored program.

changes security context for triggers
switch to new memroot
call sp_head::execute
restore old memroot
restores security context

Parameters:

thd	Thread context
db	database name
table	table name
grant_info	GRANT_INFO structure to be filled with information about definer's privileges on subject table

Todo:

TODO: we should create sp_rcontext once per command and reuse it on subsequent executions of a trigger.

Returns:: Error status.

MEM_ROOT* sp_head::get_current_mem_root ( ) const [inline]

Returns:: currently used mem-root.

sp_instr* sp_head::get_instr ( uint i ) [inline]

Get SP-instruction at given index.

NOTE: it is important to have *unsigned* int here, sometimes we get (-1) passed here, so it get's converted to MAX_INT, and the result of the function call is NULL.

MEM_ROOT* sp_head::get_persistent_mem_root ( ) const [inline]

Returns:: SP-persistent mem-root. Instructions and expressions are stored in its memory between executions.

sp_pcontext* sp_head::get_root_parsing_context ( ) const [inline]

Returns:: root parsing context for this stored program.

bool sp_head::is_not_allowed_in_function ( const char * where ) [inline]

Check if this stored routine contains statements disallowed in a stored function or trigger, and set an appropriate error message if this is the case.

bool sp_head::modifies_data ( ) const [inline]

Returns true if any substatement in the routine directly (not through another routine) modifies data/changes table.

See also:: Comment for MODIFIES_DATA flag.

void sp_head::optimize ( )

Do some minimal optimization of the code:

Mark used instructions
While doing this, shortcut jumps to jump instructions
Compact the code, removing unused instructions.

This is the main mark and move loop; it relies on the following methods in sp_instr and its subclasses:

opt_mark() : Mark instruction as reachable
opt_shortcut_jump(): Shortcut jumps to the final destination; used by opt_mark().
opt_move() : Update moved instruction
set_destination() : Set the new destination (jump instructions only)

bool sp_head::reset_lex ( THD * thd )

Reset LEX-object during parsing, before we parse a sub statement.

Parameters:

thd	Thread context.

Returns:: Error status.

bool sp_head::restore_lex ( THD * thd )

Restore LEX-object during parsing, after we have parsed a sub statement.

Parameters:

thd	Thread context.

Returns:: Error status.

bool sp_head::set_security_ctx	(	THD *	thd,
		Security_context **	save_ctx
	)

Change routine security context, and check if there is an EXECUTE privilege in new context. If there is no EXECUTE privilege, change the context back and return an error.

Parameters:

	thd	Thread context.
[out]	save_ctx	Where to save the old security context.

Todo:: Cache if the definer has the rights to use the object on the first usage and reset the cache only if someone does a GRANT statement that 'may' affect this.

Returns:: Error status.

bool sp_head::show_create_routine	(	THD *	thd,
		enum_sp_type	type
	)

Implement SHOW CREATE statement for stored routines.

Parameters:

thd	Thread context.
type	Stored routine type (SP_TYPE_PROCEDURE or SP_TYPE_FUNCTION)

Returns:: Error status.

bool sp_head::show_routine_code ( THD * thd )

Return the routine instructions as a result set.

Returns:: Error status.

ulong sp_head::sp_cache_version ( ) const [inline]

Get the value of the SP cache version, as remembered when the routine was inserted into the cache.

Friends And Related Function Documentation

sp_head* sp_start_parsing	(	THD *	,
		enum_sp_type	,
		sp_name *
	)		`[friend]`

Start parsing of a stored program.

This function encapsulates all the steps necessary to initialize sp_head to start parsing SP.

Every successful call of sp_start_parsing() must finish with sp_finish_parsing().

Parameters:

thd	Thread context.
sp_type	The stored program type
sp_name	The stored progam name

Returns:: properly initialized sp_head-instance in case of success, or NULL is case of out-of-memory error.

Member Data Documentation

SQL_I_List<Item_trigger_field> sp_head::m_cur_instr_trig_field_items

List of all the Item_trigger_field items created while parsing sp instruction. After parsing, in add_instr method this list is moved to per instruction Item_trigger_field list "sp_lex_instr::m_trig_field_list".

sp_head* sp_head::m_first_free_instance

Pointer to the first free (non-INVOKED) routine in the list of cached instances for this SP. This pointer is set only for the first SP in the list of instances (see above m_first_cached_sp pointer). The pointer equal to 0 if we have no free instances. For non-first instance value of this pointer meaningless (point to itself);

sp_head* sp_head::m_last_cached_sp

Pointer to the last element in the list of instances of the SP. For non-first instance value of this pointer meaningless (point to itself);

SQL_I_List<SQL_I_List<Item_trigger_field> > sp_head::m_list_of_trig_fields_item_lists

List of item (Item_trigger_field objects)'s lists representing fields in old/new version of row in trigger. We use this list for checking whether all such fields are valid or not at trigger creation time and for binding these fields to TABLE object at table open (although for latter pointer to table being opened is probably enough).

sp_head* sp_head::m_next_cached_sp

A list of diferent recursion level instances for the same procedure. For every recursion level we have a sp_head instance. This instances connected in the list. The list ordered by increasing recursion level (m_recursion_level).

Create_field sp_head::m_return_field_def

Definition of the RETURN-field (from the RETURNS-clause). It's used (and valid) for stored functions only.

sql_mode_t sp_head::m_sql_mode

The value of sql_mode system variable at the CREATE-time.

It should be stored along with the character sets in the Stored_program_creation_ctx.

HASH sp_head::m_sroutines

Set containing names of stored routines used by this routine. Note that unlike elements of similar set for statement elements of this set are not linked in one list. Because of this we are able save memory by using for this set same objects that are used in 'sroutines' sets for statements of which this stored routine consists.

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

sp_head.h
sp_head.cc

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Friends

Detailed Description

Member Enumeration Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation