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/*****************************************************************************
Copyright (c) 1996, 2025, Oracle and/or its affiliates.
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 designed to work 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 either included with
the program or referenced in the documentation.
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
*****************************************************************************/
/** @file include/pars0pars.h
SQL parser
Created 11/19/1996 Heikki Tuuri
*******************************************************/
#ifndef pars0pars_h
#define pars0pars_h
#include "pars0types.h"
#include "que0types.h"
#include "row0mysql.h"
#include "row0types.h"
#include "trx0types.h"
#include "univ.i"
#include "usr0types.h"
#include "ut0vec.h"
/** Type of the user functions. The first argument is always InnoDB-supplied
and varies in type, while 'user_arg' is a user-supplied argument. The
meaning of the return type also varies. See the individual use cases, e.g.
the FETCH statement, for details on them. */
typedef bool (*pars_user_func_cb_t)(void *arg, void *user_arg);
/** If the following is set true, the parser will emit debugging
information */
extern int yydebug;
/* Global variable used while parsing a single procedure or query : the code is
NOT re-entrant */
extern sym_tab_t *pars_sym_tab_global;
/** Mutex to protect the sql parser */
extern ib_mutex_t pars_mutex;
extern pars_res_word_t pars_to_binary_token;
extern pars_res_word_t pars_substr_token;
extern pars_res_word_t pars_concat_token;
extern pars_res_word_t pars_length_token;
extern pars_res_word_t pars_instr_token;
extern pars_res_word_t pars_count_token;
extern pars_res_word_t pars_sum_token;
extern pars_res_word_t pars_distinct_token;
extern pars_res_word_t pars_binary_token;
extern pars_res_word_t pars_blob_token;
extern pars_res_word_t pars_int_token;
extern pars_res_word_t pars_bigint_token;
extern pars_res_word_t pars_char_token;
extern pars_res_word_t pars_float_token;
extern pars_res_word_t pars_update_token;
extern pars_res_word_t pars_asc_token;
extern pars_res_word_t pars_desc_token;
extern pars_res_word_t pars_open_token;
extern pars_res_word_t pars_close_token;
extern pars_res_word_t pars_share_token;
extern pars_res_word_t pars_unique_token;
extern pars_res_word_t pars_clustered_token;
extern ulint pars_star_denoter;
/* Procedure parameter types */
#define PARS_INPUT 0
#define PARS_OUTPUT 1
#define PARS_NOT_PARAM 2
int yyparse(void);
/** Initialize for the internal parser */
void pars_init();
/** Clean up the internal parser */
void pars_close();
/** Parses an SQL string returning the query graph.
@return own: the query graph */
que_t *pars_sql(pars_info_t *info, /*!< in: extra information, or NULL */
const char *str); /*!< in: SQL string */
/** Retrieves characters to the lexical analyzer.
@param[in,out] buf Buffer where to copy
@param[in] max_size Maximum number of characters which fit in the buffer
@return number of characters copied or 0 on EOF
*/
int pars_get_lex_chars(char *buf, size_t max_size);
/** Called by yyparse on error. */
void yyerror(const char *s); /*!< in: error message string */
/** Parses a variable declaration.
@return own: symbol table node of type SYM_VAR */
sym_node_t *pars_variable_declaration(
sym_node_t *node, /*!< in: symbol table node allocated for the
id of the variable */
pars_res_word_t *type); /*!< in: pointer to a type token */
/** Parses a function expression.
@return own: function node in a query tree */
func_node_t *pars_func(
que_node_t *res_word, /*!< in: function name reserved word */
que_node_t *arg); /*!< in: first argument in the argument list */
/*************************************************************************
Rebind a LIKE search string. NOTE: We ignore any '%' characters embedded
within the search string.
@return own: function node in a query tree */
int pars_like_rebind(sym_node_t *node, /* in: The search string node.*/
const byte *ptr, /* in: literal to (re) bind */
ulint len); /* in: length of literal to (re) bind*/
/** Parses an operator expression.
@return own: function node in a query tree */
func_node_t *pars_op(int func, /*!< in: operator token code */
que_node_t *arg1, /*!< in: first argument */
que_node_t *arg2); /*!< in: second argument or NULL for an
unary operator */
/** Parses an ORDER BY clause. Order by a single column only is supported.
@return own: order-by node in a query tree */
order_node_t *pars_order_by(
sym_node_t *column, /*!< in: column name */
pars_res_word_t *asc); /*!< in: &pars_asc_token or pars_desc_token */
/** Parses a select list; creates a query graph node for the whole SELECT
statement.
@return own: select node in a query tree */
sel_node_t *pars_select_list(
que_node_t *select_list, /*!< in: select list */
sym_node_t *into_list); /*!< in: variables list or NULL */
/** Parses a cursor declaration.
@return sym_node */
que_node_t *pars_cursor_declaration(
sym_node_t *sym_node, /*!< in: cursor id node in the symbol
table */
sel_node_t *select_node); /*!< in: select node */
/** Parses a function declaration.
@return sym_node */
que_node_t *pars_function_declaration(
sym_node_t *sym_node); /*!< in: function id node in the symbol
table */
/** Parses a select statement.
@return own: select node in a query tree */
sel_node_t *pars_select_statement(
sel_node_t *select_node, /*!< in: select node already containing
the select list */
sym_node_t *table_list, /*!< in: table list */
que_node_t *search_cond, /*!< in: search condition or NULL */
pars_res_word_t *for_update, /*!< in: NULL or &pars_update_token */
pars_res_word_t *consistent_read, /*!< in: NULL or
&pars_consistent_token */
order_node_t *order_by); /*!< in: NULL or an order-by node */
/** Parses a column assignment in an update.
@return column assignment node */
col_assign_node_t *pars_column_assignment(
sym_node_t *column, /*!< in: column to assign */
que_node_t *exp); /*!< in: value to assign */
/** Parses a delete or update statement start.
@return own: update node in a query tree */
upd_node_t *pars_update_statement_start(
bool is_delete, /*!< in: true if delete */
sym_node_t *table_sym, /*!< in: table name node */
col_assign_node_t *col_assign_list); /*!< in: column assignment list, NULL
if delete */
/** Parses an update or delete statement.
@return own: update node in a query tree */
upd_node_t *pars_update_statement(
upd_node_t *node, /*!< in: update node */
sym_node_t *cursor_sym, /*!< in: pointer to a cursor entry in
the symbol table or NULL */
que_node_t *search_cond); /*!< in: search condition or NULL */
/** Parses an insert statement.
@return own: update node in a query tree */
ins_node_t *pars_insert_statement(
sym_node_t *table_sym, /*!< in: table name node */
que_node_t *values_list, /*!< in: value expression list or NULL */
sel_node_t *select); /*!< in: select condition or NULL */
/** Parses a procedure parameter declaration.
@return own: symbol table node of type SYM_VAR */
sym_node_t *pars_parameter_declaration(
sym_node_t *node, /*!< in: symbol table node allocated for the
id of the parameter */
ulint param_type,
/*!< in: PARS_INPUT or PARS_OUTPUT */
pars_res_word_t *type); /*!< in: pointer to a type token */
/** Parses an elsif element.
@return elsif node */
elsif_node_t *pars_elsif_element(
que_node_t *cond, /*!< in: if-condition */
que_node_t *stat_list); /*!< in: statement list */
/** Parses an if-statement.
@return if-statement node */
if_node_t *pars_if_statement(
que_node_t *cond, /*!< in: if-condition */
que_node_t *stat_list, /*!< in: statement list */
que_node_t *else_part); /*!< in: else-part statement list */
/** Parses a for-loop-statement.
@return for-statement node */
for_node_t *pars_for_statement(
sym_node_t *loop_var, /*!< in: loop variable */
que_node_t *loop_start_limit, /*!< in: loop start expression */
que_node_t *loop_end_limit, /*!< in: loop end expression */
que_node_t *stat_list); /*!< in: statement list */
/** Parses a while-statement.
@return while-statement node */
while_node_t *pars_while_statement(
que_node_t *cond, /*!< in: while-condition */
que_node_t *stat_list); /*!< in: statement list */
/** Parses an exit statement.
@return exit statement node */
exit_node_t *pars_exit_statement(void);
/** Parses a return-statement.
@return return-statement node */
return_node_t *pars_return_statement(void);
/** Parses an assignment statement.
@return assignment statement node */
assign_node_t *pars_assignment_statement(
sym_node_t *var, /*!< in: variable to assign */
que_node_t *val); /*!< in: value to assign */
/** Parses a fetch statement. into_list or user_func (but not both) must be
non-NULL.
@return fetch statement node */
fetch_node_t *pars_fetch_statement(
sym_node_t *cursor, /*!< in: cursor node */
sym_node_t *into_list, /*!< in: variables to set, or NULL */
sym_node_t *user_func); /*!< in: user function name, or NULL */
/** Parses an open or close cursor statement.
@return fetch statement node */
open_node_t *pars_open_statement(ulint type, /*!< in: ROW_SEL_OPEN_CURSOR
or ROW_SEL_CLOSE_CURSOR */
sym_node_t *cursor); /*!< in: cursor node */
/** Parses a commit statement.
@return own: commit node struct */
commit_node_t *pars_commit_statement(void);
/** Parses a rollback statement.
@return own: rollback node struct */
roll_node_t *pars_rollback_statement(void);
/** Parses a column definition at a table creation.
@return column sym table node */
sym_node_t *pars_column_def(sym_node_t *sym_node, /*!< in: column node in the
symbol table */
pars_res_word_t *type, /*!< in: data type */
sym_node_t *len, /*!< in: length of column, or
NULL */
void *is_unsigned, /*!< in: if not NULL, column
is of type UNSIGNED. */
void *is_not_null); /*!< in: if not NULL, column
is of type NOT NULL. */
/** Parses a table creation operation.
@param[in] table_sym table name node in the symbol table
@param[in] column_defs list of column names
@param[in] not_fit_in_memory a non-NULL pointer means that this is a
table which in simulations should be
simulated as not fitting in memory;
thread is put to sleep to simulate disk
accesses; NOTE that this flag is not
stored to the data dictionary on disk,
and the database will forget about
non-NULL value if it has to reload the
table definition from disk
@param[in] compact non-NULL if COMPACT table
@param[in] block_size block size (can be NULL)
@return table create subgraph */
tab_node_t *pars_create_table(sym_node_t *table_sym, sym_node_t *column_defs,
sym_node_t *compact, sym_node_t *block_size,
void *not_fit_in_memory);
/** Parses an index creation operation.
@param[in] unique_def Not NULL if a unique index.
@param[in] clustered_def Not NULL if a clustered index.
@param[in] index_sym Index name node in the symbol table.
@param[in] table_sym Table name node in the symbol table.
@param[in] column_list List of column names.
@return index create subgraph */
ind_node_t *pars_create_index(pars_res_word_t *unique_def,
pars_res_word_t *clustered_def,
sym_node_t *index_sym, sym_node_t *table_sym,
sym_node_t *column_list);
/** Parses a procedure definition.
@return query fork node */
que_fork_t *pars_procedure_definition(
sym_node_t *sym_node, /*!< in: procedure id node in the symbol
table */
sym_node_t *param_list, /*!< in: parameter declaration list */
que_node_t *stat_list); /*!< in: statement list */
/** Completes a query graph by adding query thread and fork nodes
above it and prepares the graph for running. The fork created is of
type QUE_FORK_MYSQL_INTERFACE.
@param[in] node root node for an incomplete query
graph, or NULL for dummy graph
@param[in] trx transaction handle
@param[in] heap memory heap from which allocated
@param[in] prebuilt row prebuilt structure
@return query thread node to run */
[[nodiscard]] que_thr_t *pars_complete_graph_for_exec(que_node_t *node,
trx_t *trx,
mem_heap_t *heap,
row_prebuilt_t *prebuilt);
/** Create parser info struct.
@return own: info struct */
pars_info_t *pars_info_create(void);
/** Free info struct and everything it contains. */
void pars_info_free(pars_info_t *info); /*!< in, own: info struct */
/** Add bound literal.
@param[in] info Info struct
@param[in] name Name
@param[in] address Address
@param[in] length Length of data
@param[in] type Type, e.g. data_fixbinary
@param[in] prtype Precise type, e.g. data_unsigned */
void pars_info_add_literal(pars_info_t *info, const char *name,
const void *address, ulint length, ulint type,
ulint prtype);
/** Equivalent to pars_info_add_literal(info, name, str, strlen(str),
DATA_VARCHAR, DATA_ENGLISH).
@param[in] info Info struct
@param[in] name Name
@param[in] str String */
void pars_info_add_str_literal(pars_info_t *info, const char *name,
const char *str);
/********************************************************************
If the literal value already exists then it rebinds otherwise it
creates a new entry.*/
void pars_info_bind_literal(pars_info_t *info, /* in: info struct */
const char *name, /* in: name */
const void *address, /* in: address */
ulint length, /* in: length of data */
ulint type, /* in: type, e.g. DATA_FIXBINARY */
ulint prtype); /* in: precise type, e.g. */
/** If the literal value already exists then it rebinds otherwise it
creates a new entry.
@param[in] info Info struct
@param[in] name Name
@param[in] str String
@param[in] str_len String length */
void pars_info_bind_varchar_literal(pars_info_t *info, const char *name,
const byte *str, ulint str_len);
/** If the literal value already exists then it rebinds otherwise it creates a
new entry.
@param[in] info Info struct
@param[in] name Name
@param[in] val Value */
void pars_info_bind_int4_literal(pars_info_t *info, const char *name,
const uint32_t *val);
/** If the literal value already exists then it rebinds otherwise it creates a
new entry.
@param[in] info Info struct
@param[in] name Name
@param[in] val Value */
void pars_info_bind_int8_literal(pars_info_t *info, const char *name,
const uint64_t *val);
/** Add user function.
@param[in] info Info struct
@param[in] name Function name
@param[in] func Function address
@param[in] arg User-supplied argument */
void pars_info_bind_function(pars_info_t *info, const char *name,
pars_user_func_cb_t func, void *arg);
/** Add bound id.
@param[in] info info struct
@param[in] copy_name copy name if true
@param[in] name name
@param[in] id id */
void pars_info_bind_id(pars_info_t *info, bool copy_name, const char *name,
const char *id);
/** Equivalent to:
char buf[4];
mach_write_to_4(buf, val);
pars_info_add_literal(info, name, buf, 4, DATA_INT, 0);
except that the buffer is dynamically allocated from the info struct's
heap. */
void pars_info_add_int4_literal(pars_info_t *info, /*!< in: info struct */
const char *name, /*!< in: name */
lint val); /*!< in: value */
/** Equivalent to:
char buf[8];
mach_write_to_8(buf, val);
pars_info_add_literal(info, name, buf, 8, DATA_FIXBINARY, 0);
except that the buffer is dynamically allocated from the info struct's
heap. */
void pars_info_add_ull_literal(pars_info_t *info, /*!< in: info struct */
const char *name, /*!< in: name */
uint64_t val); /*!< in: value */
/** If the literal value already exists then it rebinds otherwise it
creates a new entry.
@param[in] info Info struct
@param[in] name Name
@param[in] val Value */
void pars_info_bind_ull_literal(pars_info_t *info, const char *name,
const uint64_t *val);
/** Add bound id.
@param[in] info info struct
@param[in] name name
@param[in] id id */
void pars_info_add_id(pars_info_t *info, const char *name, const char *id);
/** Get bound literal with the given name.
@return bound literal, or NULL if not found */
pars_bound_lit_t *pars_info_get_bound_lit(
pars_info_t *info, /*!< in: info struct */
const char *name); /*!< in: bound literal name to find */
/** Get bound identifier with the given name.
@param[in] info info struct
@param[in] name bound id name to find
@return bound id, or NULL if not found */
pars_bound_id_t *pars_info_get_bound_id(pars_info_t *info, const char *name);
/** Release any resources used by the lexer. */
void pars_lexer_close(void);
/** Extra information supplied for pars_sql(). */
struct pars_info_t {
mem_heap_t *heap; /*!< our own memory heap */
ib_vector_t *funcs; /*!< user functions, or NUll
(pars_user_func_t*) */
ib_vector_t *bound_lits; /*!< bound literals, or NULL
(pars_bound_lit_t*) */
ib_vector_t *bound_ids; /*!< bound ids, or NULL
(pars_bound_id_t*) */
bool graph_owns_us; /*!< if true (which is the default),
que_graph_free() will free us */
};
/** User-supplied function and argument. */
struct pars_user_func_t {
const char *name; /*!< function name */
pars_user_func_cb_t func; /*!< function address */
void *arg; /*!< user-supplied argument */
};
/** Bound literal. */
struct pars_bound_lit_t {
const char *name; /*!< name */
const void *address; /*!< address */
ulint length; /*!< length of data */
ulint type; /*!< type, e.g. DATA_FIXBINARY */
ulint prtype; /*!< precise type, e.g. DATA_UNSIGNED */
sym_node_t *node; /*!< symbol node */
};
/** Bound identifier. */
struct pars_bound_id_t {
const char *name; /*!< name */
const char *id; /*!< identifier */
};
/** Struct used to denote a reserved word in a parsing tree */
struct pars_res_word_t {
int code; /*!< the token code for the reserved word from
pars0grm.h */
};
/** A predefined function or operator node in a parsing tree; this construct
is also used for some non-functions like the assignment ':=' */
struct func_node_t {
que_common_t common; /*!< type: QUE_NODE_FUNC */
int func; /*!< token code of the function name */
ulint fclass; /*!< class of the function */
que_node_t *args; /*!< argument(s) of the function */
UT_LIST_NODE_T(func_node_t) cond_list;
/*!< list of comparison conditions; defined
only for comparison operator nodes except,
presently, for OPT_SCROLL_TYPE ones */
UT_LIST_NODE_T(func_node_t) func_node_list;
/*!< list of function nodes in a parsed
query graph */
};
UT_LIST_NODE_GETTER_DEFINITION(func_node_t, cond_list)
UT_LIST_NODE_GETTER_DEFINITION(func_node_t, func_node_list)
/** An order-by node in a select */
struct order_node_t {
que_common_t common; /*!< type: QUE_NODE_ORDER */
sym_node_t *column; /*!< order-by column */
bool asc; /*!< true if ascending, false if descending */
};
/** Procedure definition node */
struct proc_node_t {
que_common_t common; /*!< type: QUE_NODE_PROC */
sym_node_t *proc_id; /*!< procedure name symbol in the symbol
table of this same procedure */
sym_node_t *param_list; /*!< input and output parameters */
que_node_t *stat_list; /*!< statement list */
sym_tab_t *sym_tab; /*!< symbol table of this procedure */
};
/** elsif-element node */
struct elsif_node_t {
que_common_t common; /*!< type: QUE_NODE_ELSIF */
que_node_t *cond; /*!< if condition */
que_node_t *stat_list; /*!< statement list */
};
/** if-statement node */
struct if_node_t {
que_common_t common; /*!< type: QUE_NODE_IF */
que_node_t *cond; /*!< if condition */
que_node_t *stat_list; /*!< statement list */
que_node_t *else_part; /*!< else-part statement list */
elsif_node_t *elsif_list; /*!< elsif element list */
};
/** while-statement node */
struct while_node_t {
que_common_t common; /*!< type: QUE_NODE_WHILE */
que_node_t *cond; /*!< while condition */
que_node_t *stat_list; /*!< statement list */
};
/** for-loop-statement node */
struct for_node_t {
que_common_t common; /*!< type: QUE_NODE_FOR */
sym_node_t *loop_var; /*!< loop variable: this is the
dereferenced symbol from the
variable declarations, not the
symbol occurrence in the for loop
definition */
que_node_t *loop_start_limit; /*!< initial value of loop variable */
que_node_t *loop_end_limit; /*!< end value of loop variable */
lint loop_end_value; /*!< evaluated value for the end value:
it is calculated only when the loop
is entered, and will not change within
the loop */
que_node_t *stat_list; /*!< statement list */
};
/** exit statement node */
struct exit_node_t {
que_common_t common; /*!< type: QUE_NODE_EXIT */
};
/** return-statement node */
struct return_node_t {
que_common_t common; /*!< type: QUE_NODE_RETURN */
};
/** Assignment statement node */
struct assign_node_t {
que_common_t common; /*!< type: QUE_NODE_ASSIGNMENT */
sym_node_t *var; /*!< variable to set */
que_node_t *val; /*!< value to assign */
};
/** Column assignment node */
struct col_assign_node_t {
que_common_t common; /*!< type: QUE_NODE_COL_ASSIGN */
sym_node_t *col; /*!< column to set */
que_node_t *val; /*!< value to assign */
};
/** Classes of functions */
/** @{ */
#define PARS_FUNC_ARITH 1 /*!< +, -, *, / */
#define PARS_FUNC_LOGICAL 2 /*!< AND, OR, NOT */
#define PARS_FUNC_CMP 3 /*!< comparison operators */
#define PARS_FUNC_PREDEFINED 4 /*!< TO_NUMBER, SUBSTR, ... */
#define PARS_FUNC_AGGREGATE 5 /*!< COUNT, DISTINCT, SUM */
#define PARS_FUNC_OTHER \
6 /*!< these are not real functions, \
e.g., := */
/** @} */
#include "pars0pars.ic"
#endif
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