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+/* -*- C++ -*- */
+/* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
+ Copyright (c) 2009, 2020, MariaDB Corporation.
+
+ 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 _SP_PCONTEXT_H_
+#define _SP_PCONTEXT_H_
+
+#ifdef USE_PRAGMA_INTERFACE
+#pragma interface /* gcc class implementation */
+#endif
+
+#include "sql_string.h" // LEX_STRING
+#include "field.h" // Create_field
+#include "sql_array.h" // Dynamic_array
+
+
+/// This class represents a stored program variable or a parameter
+/// (also referenced as 'SP-variable').
+
+class sp_variable : public Sql_alloc
+{
+public:
+ enum enum_mode
+ {
+ MODE_IN,
+ MODE_OUT,
+ MODE_INOUT
+ };
+
+ /// Name of the SP-variable.
+ LEX_CSTRING name;
+
+ /// Mode of the SP-variable.
+ enum_mode mode;
+
+ /// The index to the variable's value in the runtime frame.
+ ///
+ /// It is calculated during parsing and used when creating sp_instr_set
+ /// instructions and Item_splocal items. I.e. values are set/referred by
+ /// array indexing in runtime.
+ uint offset;
+
+ /// Default value of the SP-variable (if any).
+ Item *default_value;
+
+ /// Full type information (field meta-data) of the SP-variable.
+ Spvar_definition field_def;
+
+ /// Field-type of the SP-variable.
+ const Type_handler *type_handler() const { return field_def.type_handler(); }
+
+public:
+ sp_variable(const LEX_CSTRING *name_arg, uint offset_arg)
+ :Sql_alloc(),
+ name(*name_arg),
+ mode(MODE_IN),
+ offset(offset_arg),
+ default_value(NULL)
+ { }
+ /*
+ Find a ROW field by its qualified name.
+ @param var_name - the name of the variable
+ @param field_name - the name of the variable field
+ @param[OUT] row_field_offset - the index of the field
+
+ @retval NULL if the variable with the given name was not found,
+ or it is not a row variable, or it does not have a field
+ with the given name, or a non-null pointer otherwise.
+ row_field_offset[0] is set only when the method returns !NULL.
+ */
+ const Spvar_definition *find_row_field(const LEX_CSTRING *var_name,
+ const LEX_CSTRING *field_name,
+ uint *row_field_offset);
+};
+
+///////////////////////////////////////////////////////////////////////////
+
+/// This class represents an SQL/PSM label. Can refer to the identifier
+/// used with the "label_name:" construct which may precede some SQL/PSM
+/// statements, or to an implicit implementation-dependent identifier which
+/// the parser inserts before a high-level flow control statement such as
+/// IF/WHILE/REPEAT/LOOP, when such statement is rewritten into a
+/// combination of low-level jump/jump_if instructions and labels.
+
+
+class sp_label : public Sql_alloc
+{
+public:
+ enum enum_type
+ {
+ /// Implicit label generated by parser.
+ IMPLICIT,
+
+ /// Label at BEGIN.
+ BEGIN,
+
+ /// Label at iteration control
+ ITERATION,
+
+ /// Label for jump
+ GOTO
+ };
+
+ /// Name of the label.
+ LEX_CSTRING name;
+
+ /// Instruction pointer of the label.
+ uint ip;
+
+ /// Type of the label.
+ enum_type type;
+
+ /// Scope of the label.
+ class sp_pcontext *ctx;
+
+public:
+ sp_label(const LEX_CSTRING *_name,
+ uint _ip, enum_type _type, sp_pcontext *_ctx)
+ :Sql_alloc(),
+ name(*_name),
+ ip(_ip),
+ type(_type),
+ ctx(_ctx)
+ { }
+};
+
+
+///////////////////////////////////////////////////////////////////////////
+
+/// This class represents condition-value term in DECLARE CONDITION or
+/// DECLARE HANDLER statements. sp_condition_value has little to do with
+/// SQL-conditions.
+///
+/// In some sense, this class is a union -- a set of filled attributes
+/// depends on the sp_condition_value::type value.
+
+class sp_condition_value : public Sql_alloc, public Sql_state_errno
+{
+ bool m_is_user_defined;
+public:
+ enum enum_type
+ {
+ ERROR_CODE,
+ SQLSTATE,
+ WARNING,
+ NOT_FOUND,
+ EXCEPTION
+ };
+
+ /// Type of the condition value.
+ enum_type type;
+
+public:
+ sp_condition_value(uint _mysqlerr)
+ :Sql_alloc(),
+ Sql_state_errno(_mysqlerr),
+ m_is_user_defined(false),
+ type(ERROR_CODE)
+ { }
+
+ sp_condition_value(uint _mysqlerr, const char *_sql_state)
+ :Sql_alloc(),
+ Sql_state_errno(_mysqlerr, _sql_state),
+ m_is_user_defined(false),
+ type(ERROR_CODE)
+ { }
+
+ sp_condition_value(const char *_sql_state, bool is_user_defined= false)
+ :Sql_alloc(),
+ Sql_state_errno(0, _sql_state),
+ m_is_user_defined(is_user_defined),
+ type(SQLSTATE)
+ { }
+
+ sp_condition_value(enum_type _type)
+ :Sql_alloc(),
+ m_is_user_defined(false),
+ type(_type)
+ {
+ DBUG_ASSERT(type != ERROR_CODE && type != SQLSTATE);
+ }
+
+ /// Check if two instances of sp_condition_value are equal or not.
+ ///
+ /// @param cv another instance of sp_condition_value to check.
+ ///
+ /// @return true if the instances are equal, false otherwise.
+ bool equals(const sp_condition_value *cv) const;
+
+
+ /**
+ Checks if this condition is OK for search.
+ See also sp_context::find_handler().
+
+ @param identity - The condition identity
+ @param found_cv - A previously found matching condition or NULL.
+ @return true - If the current value matches identity and
+ makes a stronger match than the previously
+ found condition found_cv.
+ @return false - If the current value does not match identity,
+ of the current value makes a weaker match than found_cv.
+ */
+ bool matches(const Sql_condition_identity &identity,
+ const sp_condition_value *found_cv) const;
+
+ Sql_user_condition_identity get_user_condition_identity() const
+ {
+ return Sql_user_condition_identity(m_is_user_defined ? this : NULL);
+ }
+};
+
+
+class sp_condition_value_user_defined: public sp_condition_value
+{
+public:
+ sp_condition_value_user_defined()
+ :sp_condition_value("45000", true)
+ { }
+};
+
+
+///////////////////////////////////////////////////////////////////////////
+
+/// This class represents 'DECLARE CONDITION' statement.
+/// sp_condition has little to do with SQL-conditions.
+
+class sp_condition : public Sql_alloc
+{
+public:
+ /// Name of the condition.
+ LEX_CSTRING name;
+
+ /// Value of the condition.
+ sp_condition_value *value;
+
+public:
+ sp_condition(const LEX_CSTRING *name_arg, sp_condition_value *value_arg)
+ :Sql_alloc(),
+ name(*name_arg),
+ value(value_arg)
+ { }
+ sp_condition(const char *name_arg, size_t name_length_arg,
+ sp_condition_value *value_arg)
+ :value(value_arg)
+ {
+ name.str= name_arg;
+ name.length= name_length_arg;
+ }
+ bool eq_name(const LEX_CSTRING *str) const
+ {
+ return system_charset_info->strnncoll(name.str, name.length,
+ str->str, str->length) == 0;
+ }
+};
+
+
+///////////////////////////////////////////////////////////////////////////
+
+/**
+ class sp_pcursor.
+ Stores information about a cursor:
+ - Cursor's name in LEX_STRING.
+ - Cursor's formal parameter descriptions.
+
+ Formal parameter descriptions reside in a separate context block,
+ pointed by the "m_param_context" member.
+
+ m_param_context can be NULL. This means a cursor with no parameters.
+ Otherwise, the number of variables in m_param_context means
+ the number of cursor's formal parameters.
+
+ Note, m_param_context can be not NULL, but have no variables.
+ This is also means a cursor with no parameters (similar to NULL).
+*/
+class sp_pcursor: public LEX_CSTRING
+{
+ class sp_pcontext *m_param_context; // Formal parameters
+ class sp_lex_cursor *m_lex; // The cursor statement LEX
+public:
+ sp_pcursor(const LEX_CSTRING *name, class sp_pcontext *param_ctx,
+ class sp_lex_cursor *lex)
+ :LEX_CSTRING(*name), m_param_context(param_ctx), m_lex(lex)
+ { }
+ class sp_pcontext *param_context() const { return m_param_context; }
+ class sp_lex_cursor *lex() const { return m_lex; }
+ bool check_param_count_with_error(uint param_count) const;
+};
+
+
+///////////////////////////////////////////////////////////////////////////
+
+/// This class represents 'DECLARE HANDLER' statement.
+
+class sp_handler : public Sql_alloc
+{
+public:
+ /// Enumeration of possible handler types.
+ /// Note: UNDO handlers are not (and have never been) supported.
+ enum enum_type
+ {
+ EXIT,
+ CONTINUE
+ };
+
+ /// Handler type.
+ enum_type type;
+
+ /// Conditions caught by this handler.
+ List<sp_condition_value> condition_values;
+
+public:
+ /// The constructor.
+ ///
+ /// @param _type SQL-handler type.
+ sp_handler(enum_type _type)
+ :Sql_alloc(),
+ type(_type)
+ { }
+};
+
+///////////////////////////////////////////////////////////////////////////
+
+/// The class represents parse-time context, which keeps track of declared
+/// variables/parameters, conditions, handlers, cursors and labels.
+///
+/// sp_pcontext objects are organized in a tree according to the following
+/// rules:
+/// - one sp_pcontext object corresponds for for each BEGIN..END block;
+/// - one sp_pcontext object corresponds for each exception handler;
+/// - one additional sp_pcontext object is created to contain
+/// Stored Program parameters.
+///
+/// sp_pcontext objects are used both at parse-time and at runtime.
+///
+/// During the parsing stage sp_pcontext objects are used:
+/// - to look up defined names (e.g. declared variables and visible
+/// labels);
+/// - to check for duplicates;
+/// - for error checking;
+/// - to calculate offsets to be used at runtime.
+///
+/// During the runtime phase, a tree of sp_pcontext objects is used:
+/// - for error checking (e.g. to check correct number of parameters);
+/// - to resolve SQL-handlers.
+
+class sp_pcontext : public Sql_alloc
+{
+public:
+ enum enum_scope
+ {
+ /// REGULAR_SCOPE designates regular BEGIN ... END blocks.
+ REGULAR_SCOPE,
+
+ /// HANDLER_SCOPE designates SQL-handler blocks.
+ HANDLER_SCOPE
+ };
+
+ class Lex_for_loop: public Lex_for_loop_st
+ {
+ public:
+ Lex_for_loop() { init(); }
+ };
+
+public:
+ sp_pcontext();
+ ~sp_pcontext();
+
+
+ /// Create and push a new context in the tree.
+
+ /// @param thd thread context.
+ /// @param scope scope of the new parsing context.
+ /// @return the node created.
+ sp_pcontext *push_context(THD *thd, enum_scope scope);
+
+ /// Pop a node from the parsing context tree.
+ /// @return the parent node.
+ sp_pcontext *pop_context();
+
+ sp_pcontext *parent_context() const
+ { return m_parent; }
+
+ sp_pcontext *child_context(uint i) const
+ { return i < m_children.elements() ? m_children.at(i) : NULL; }
+
+ /// Calculate and return the number of handlers to pop between the given
+ /// context and this one.
+ ///
+ /// @param ctx the other parsing context.
+ /// @param exclusive specifies if the last scope should be excluded.
+ ///
+ /// @return the number of handlers to pop between the given context and
+ /// this one. If 'exclusive' is true, don't count the last scope we are
+ /// leaving; this is used for LEAVE where we will jump to the hpop
+ /// instructions.
+ uint diff_handlers(const sp_pcontext *ctx, bool exclusive) const;
+
+ /// Calculate and return the number of cursors to pop between the given
+ /// context and this one.
+ ///
+ /// @param ctx the other parsing context.
+ /// @param exclusive specifies if the last scope should be excluded.
+ ///
+ /// @return the number of cursors to pop between the given context and
+ /// this one. If 'exclusive' is true, don't count the last scope we are
+ /// leaving; this is used for LEAVE where we will jump to the cpop
+ /// instructions.
+ uint diff_cursors(const sp_pcontext *ctx, bool exclusive) const;
+
+ /////////////////////////////////////////////////////////////////////////
+ // SP-variables (parameters and variables).
+ /////////////////////////////////////////////////////////////////////////
+
+ /// @return the maximum number of variables used in this and all child
+ /// contexts. For the root parsing context, this gives us the number of
+ /// slots needed for variables during the runtime phase.
+ uint max_var_index() const
+ { return m_max_var_index; }
+
+ /// @return the current number of variables used in the parent contexts
+ /// (from the root), including this context.
+ uint current_var_count() const
+ { return m_var_offset + (uint)m_vars.elements(); }
+
+ /// @return the number of variables in this context alone.
+ uint context_var_count() const
+ { return (uint)m_vars.elements(); }
+
+ /// return the i-th variable on the current context
+ sp_variable *get_context_variable(uint i) const
+ {
+ DBUG_ASSERT(i < m_vars.elements());
+ return m_vars.at(i);
+ }
+
+ /*
+ Return the i-th last context variable.
+ If i is 0, then return the very last variable in m_vars.
+ */
+ sp_variable *get_last_context_variable(uint i= 0) const
+ {
+ DBUG_ASSERT(i < m_vars.elements());
+ return m_vars.at(m_vars.elements() - i - 1);
+ }
+
+ /// Add SP-variable to the parsing context.
+ ///
+ /// @param thd Thread context.
+ /// @param name Name of the SP-variable.
+ ///
+ /// @return instance of newly added SP-variable.
+ sp_variable *add_variable(THD *thd, const LEX_CSTRING *name);
+
+ /// Retrieve full type information about SP-variables in this parsing
+ /// context and its children.
+ ///
+ /// @param field_def_lst[out] Container to store type information.
+ void retrieve_field_definitions(List<Spvar_definition> *field_def_lst) const;
+
+ /// Find SP-variable by name.
+ ///
+ /// The function does a linear search (from newer to older variables,
+ /// in case we have shadowed names).
+ ///
+ /// The function is called only at parsing time.
+ ///
+ /// @param name Variable name.
+ /// @param current_scope_only A flag if we search only in current scope.
+ ///
+ /// @return instance of found SP-variable, or NULL if not found.
+ sp_variable *find_variable(const LEX_CSTRING *name, bool current_scope_only) const;
+
+ /// Find SP-variable by the offset in the root parsing context.
+ ///
+ /// The function is used for two things:
+ /// - When evaluating parameters at the beginning, and setting out parameters
+ /// at the end, of invocation. (Top frame only, so no recursion then.)
+ /// - For printing of sp_instr_set. (Debug mode only.)
+ ///
+ /// @param offset Variable offset in the root parsing context.
+ ///
+ /// @return instance of found SP-variable, or NULL if not found.
+ sp_variable *find_variable(uint offset) const;
+
+ /// Set the current scope boundary (for default values).
+ ///
+ /// @param n The number of variables to skip.
+ void declare_var_boundary(uint n)
+ { m_pboundary= n; }
+
+ /////////////////////////////////////////////////////////////////////////
+ // CASE expressions.
+ /////////////////////////////////////////////////////////////////////////
+
+ int register_case_expr()
+ { return m_num_case_exprs++; }
+
+ int get_num_case_exprs() const
+ { return m_num_case_exprs; }
+
+ bool push_case_expr_id(int case_expr_id)
+ { return m_case_expr_ids.append(case_expr_id); }
+
+ void pop_case_expr_id()
+ { m_case_expr_ids.pop(); }
+
+ int get_current_case_expr_id() const
+ { return *m_case_expr_ids.back(); }
+
+ /////////////////////////////////////////////////////////////////////////
+ // Labels.
+ /////////////////////////////////////////////////////////////////////////
+
+ sp_label *push_label(THD *thd, const LEX_CSTRING *name, uint ip,
+ sp_label::enum_type type, List<sp_label> * list);
+
+ sp_label *push_label(THD *thd, const LEX_CSTRING *name, uint ip,
+ sp_label::enum_type type)
+ { return push_label(thd, name, ip, type, &m_labels); }
+
+ sp_label *push_goto_label(THD *thd, const LEX_CSTRING *name, uint ip,
+ sp_label::enum_type type)
+ { return push_label(thd, name, ip, type, &m_goto_labels); }
+
+ sp_label *push_label(THD *thd, const LEX_CSTRING *name, uint ip)
+ { return push_label(thd, name, ip, sp_label::IMPLICIT); }
+
+ sp_label *push_goto_label(THD *thd, const LEX_CSTRING *name, uint ip)
+ { return push_goto_label(thd, name, ip, sp_label::GOTO); }
+
+ sp_label *find_label(const LEX_CSTRING *name);
+
+ sp_label *find_goto_label(const LEX_CSTRING *name, bool recusive);
+
+ sp_label *find_goto_label(const LEX_CSTRING *name)
+ { return find_goto_label(name, true); }
+
+ sp_label *find_label_current_loop_start();
+
+ sp_label *last_label()
+ {
+ sp_label *label= m_labels.head();
+
+ if (!label && m_parent)
+ label= m_parent->last_label();
+
+ return label;
+ }
+
+ sp_label *last_goto_label()
+ {
+ return m_goto_labels.head();
+ }
+
+ sp_label *pop_label()
+ { return m_labels.pop(); }
+
+ bool block_label_declare(LEX_CSTRING *label)
+ {
+ sp_label *lab= find_label(label);
+ if (lab)
+ {
+ my_error(ER_SP_LABEL_REDEFINE, MYF(0), label->str);
+ return true;
+ }
+ return false;
+ }
+
+ /////////////////////////////////////////////////////////////////////////
+ // Conditions.
+ /////////////////////////////////////////////////////////////////////////
+
+ bool add_condition(THD *thd, const LEX_CSTRING *name,
+ sp_condition_value *value);
+
+ /// See comment for find_variable() above.
+ sp_condition_value *find_condition(const LEX_CSTRING *name,
+ bool current_scope_only) const;
+
+ sp_condition_value *
+ find_declared_or_predefined_condition(THD *thd, const LEX_CSTRING *name) const;
+
+ bool declare_condition(THD *thd, const LEX_CSTRING *name,
+ sp_condition_value *val)
+ {
+ if (find_condition(name, true))
+ {
+ my_error(ER_SP_DUP_COND, MYF(0), name->str);
+ return true;
+ }
+ return add_condition(thd, name, val);
+ }
+
+ /////////////////////////////////////////////////////////////////////////
+ // Handlers.
+ /////////////////////////////////////////////////////////////////////////
+
+ sp_handler *add_handler(THD* thd, sp_handler::enum_type type);
+
+ /// This is an auxilary parsing-time function to check if an SQL-handler
+ /// exists in the current parsing context (current scope) for the given
+ /// SQL-condition. This function is used to check for duplicates during
+ /// the parsing phase.
+ ///
+ /// This function can not be used during the runtime phase to check
+ /// SQL-handler existence because it searches for the SQL-handler in the
+ /// current scope only (during runtime, current and parent scopes
+ /// should be checked according to the SQL-handler resolution rules).
+ ///
+ /// @param condition_value the handler condition value
+ /// (not SQL-condition!).
+ ///
+ /// @retval true if such SQL-handler exists.
+ /// @retval false otherwise.
+ bool check_duplicate_handler(const sp_condition_value *cond_value) const;
+
+ /// Find an SQL handler for the given SQL condition according to the
+ /// SQL-handler resolution rules. This function is used at runtime.
+ ///
+ /// @param value The error code and the SQL state
+ /// @param level The SQL condition level
+ ///
+ /// @return a pointer to the found SQL-handler or NULL.
+ sp_handler *find_handler(const Sql_condition_identity &identity) const;
+
+ /////////////////////////////////////////////////////////////////////////
+ // Cursors.
+ /////////////////////////////////////////////////////////////////////////
+
+ bool add_cursor(const LEX_CSTRING *name, sp_pcontext *param_ctx,
+ class sp_lex_cursor *lex);
+
+ /// See comment for find_variable() above.
+ const sp_pcursor *find_cursor(const LEX_CSTRING *name,
+ uint *poff, bool current_scope_only) const;
+
+ const sp_pcursor *find_cursor_with_error(const LEX_CSTRING *name,
+ uint *poff,
+ bool current_scope_only) const
+ {
+ const sp_pcursor *pcursor= find_cursor(name, poff, current_scope_only);
+ if (!pcursor)
+ {
+ my_error(ER_SP_CURSOR_MISMATCH, MYF(0), name->str);
+ return NULL;
+ }
+ return pcursor;
+ }
+ /// Find cursor by offset (for SHOW {PROCEDURE|FUNCTION} CODE only).
+ const sp_pcursor *find_cursor(uint offset) const;
+
+ const sp_pcursor *get_cursor_by_local_frame_offset(uint offset) const
+ { return &m_cursors.at(offset); }
+
+ uint cursor_offset() const
+ { return m_cursor_offset; }
+
+ uint frame_cursor_count() const
+ { return (uint)m_cursors.elements(); }
+
+ uint max_cursor_index() const
+ { return m_max_cursor_index + (uint)m_cursors.elements(); }
+
+ uint current_cursor_count() const
+ { return m_cursor_offset + (uint)m_cursors.elements(); }
+
+ void set_for_loop(const Lex_for_loop_st &for_loop)
+ {
+ m_for_loop.init(for_loop);
+ }
+ const Lex_for_loop_st &for_loop()
+ {
+ return m_for_loop;
+ }
+
+private:
+ /// Constructor for a tree node.
+ /// @param prev the parent parsing context
+ /// @param scope scope of this parsing context
+ sp_pcontext(sp_pcontext *prev, enum_scope scope);
+
+ void init(uint var_offset, uint cursor_offset, int num_case_expressions);
+
+ /* Prevent use of these */
+ sp_pcontext(const sp_pcontext &);
+ void operator=(sp_pcontext &);
+
+ sp_condition_value *find_predefined_condition(const LEX_CSTRING *name) const;
+
+private:
+ /// m_max_var_index -- number of variables (including all types of arguments)
+ /// in this context including all children contexts.
+ ///
+ /// m_max_var_index >= m_vars.elements().
+ ///
+ /// m_max_var_index of the root parsing context contains number of all
+ /// variables (including arguments) in all enclosed contexts.
+ uint m_max_var_index;
+
+ /// The maximum sub context's framesizes.
+ uint m_max_cursor_index;
+
+ /// Parent context.
+ sp_pcontext *m_parent;
+
+ /// An index of the first SP-variable in this parsing context. The index
+ /// belongs to a runtime table of SP-variables.
+ ///
+ /// Note:
+ /// - m_var_offset is 0 for root parsing context;
+ /// - m_var_offset is different for all nested parsing contexts.
+ uint m_var_offset;
+
+ /// Cursor offset for this context.
+ uint m_cursor_offset;
+
+ /// Boundary for finding variables in this context. This is the number of
+ /// variables currently "invisible" to default clauses. This is normally 0,
+ /// but will be larger during parsing of DECLARE ... DEFAULT, to get the
+ /// scope right for DEFAULT values.
+ uint m_pboundary;
+
+ int m_num_case_exprs;
+
+ /// SP parameters/variables.
+ Dynamic_array<sp_variable *> m_vars;
+
+ /// Stack of CASE expression ids.
+ Dynamic_array<int> m_case_expr_ids;
+
+ /// Stack of SQL-conditions.
+ Dynamic_array<sp_condition *> m_conditions;
+
+ /// Stack of cursors.
+ Dynamic_array<sp_pcursor> m_cursors;
+
+ /// Stack of SQL-handlers.
+ Dynamic_array<sp_handler *> m_handlers;
+
+ /*
+ In the below example the label <<lab>> has two meanings:
+ - GOTO lab : must go before the beginning of the loop
+ - CONTINUE lab : must go to the beginning of the loop
+ We solve this by storing block labels and goto labels into separate lists.
+
+ BEGIN
+ <<lab>>
+ FOR i IN a..10 LOOP
+ ...
+ GOTO lab;
+ ...
+ CONTINUE lab;
+ ...
+ END LOOP;
+ END;
+ */
+ /// List of block labels
+ List<sp_label> m_labels;
+ /// List of goto labels
+ List<sp_label> m_goto_labels;
+
+ /// Children contexts, used for destruction.
+ Dynamic_array<sp_pcontext *> m_children;
+
+ /// Scope of this parsing context.
+ enum_scope m_scope;
+
+ /// FOR LOOP characteristics
+ Lex_for_loop m_for_loop;
+}; // class sp_pcontext : public Sql_alloc
+
+
+#endif /* _SP_PCONTEXT_H_ */