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/*-------------------------------------------------------------------------
*
* parse_node.h
* Internal definitions for parser
*
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/parser/parse_node.h
*
*-------------------------------------------------------------------------
*/
#ifndef PARSE_NODE_H
#define PARSE_NODE_H
#include "nodes/parsenodes.h"
#include "utils/relcache.h"
/*
* Function signatures for parser hooks
*/
typedef struct ParseState ParseState;
typedef Node *(*PreParseColumnRefHook) (ParseState *pstate, ColumnRef *cref);
typedef Node *(*PostParseColumnRefHook) (ParseState *pstate, ColumnRef *cref, Node *var);
typedef Node *(*ParseParamRefHook) (ParseState *pstate, ParamRef *pref);
typedef Node *(*CoerceParamHook) (ParseState *pstate, Param *param,
Oid targetTypeId, int32 targetTypeMod,
int location);
/*
* State information used during parse analysis
*
* parentParseState: NULL in a top-level ParseState. When parsing a subquery,
* links to current parse state of outer query.
*
* p_sourcetext: source string that generated the raw parsetree being
* analyzed, or NULL if not available. (The string is used only to
* generate cursor positions in error messages: we need it to convert
* byte-wise locations in parse structures to character-wise cursor
* positions.)
*
* p_rtable: list of RTEs that will become the rangetable of the query.
* Note that neither relname nor refname of these entries are necessarily
* unique; searching the rtable by name is a bad idea.
*
* p_joinexprs: list of JoinExpr nodes associated with p_rtable entries.
* This is one-for-one with p_rtable, but contains NULLs for non-join
* RTEs, and may be shorter than p_rtable if the last RTE(s) aren't joins.
*
* p_joinlist: list of join items (RangeTblRef and JoinExpr nodes) that
* will become the fromlist of the query's top-level FromExpr node.
*
* p_relnamespace: list of RTEs that represents the current namespace for
* table lookup, ie, those RTEs that are accessible by qualified names.
* This may be just a subset of the rtable + joinlist, and/or may contain
* entries that are not yet added to the main joinlist.
*
* p_varnamespace: list of RTEs that represents the current namespace for
* column lookup, ie, those RTEs that are accessible by unqualified names.
* This is different from p_relnamespace because a JOIN without an alias does
* not hide the contained tables (so they must still be in p_relnamespace)
* but it does hide their columns (unqualified references to the columns must
* refer to the JOIN, not the member tables). Other special RTEs such as
* NEW/OLD for rules may also appear in just one of these lists.
*
* p_ctenamespace: list of CommonTableExprs (WITH items) that are visible
* at the moment. This is different from p_relnamespace because you have
* to make an RTE before you can access a CTE.
*
* p_future_ctes: list of CommonTableExprs (WITH items) that are not yet
* visible due to scope rules. This is used to help improve error messages.
*
* p_parent_cte: CommonTableExpr that immediately contains the current query,
* if any.
*
* p_windowdefs: list of WindowDefs representing WINDOW and OVER clauses.
* We collect these while transforming expressions and then transform them
* afterwards (so that any resjunk tlist items needed for the sort/group
* clauses end up at the end of the query tlist). A WindowDef's location in
* this list, counting from 1, is the winref number to use to reference it.
*/
struct ParseState
{
struct ParseState *parentParseState; /* stack link */
const char *p_sourcetext; /* source text, or NULL if not available */
List *p_rtable; /* range table so far */
List *p_joinexprs; /* JoinExprs for RTE_JOIN p_rtable entries */
List *p_joinlist; /* join items so far (will become FromExpr
* node's fromlist) */
List *p_relnamespace; /* current namespace for relations */
List *p_varnamespace; /* current namespace for columns */
List *p_ctenamespace; /* current namespace for common table exprs */
List *p_future_ctes; /* common table exprs not yet in namespace */
CommonTableExpr *p_parent_cte; /* this query's containing CTE */
List *p_windowdefs; /* raw representations of window clauses */
int p_next_resno; /* next targetlist resno to assign */
List *p_locking_clause; /* raw FOR UPDATE/FOR SHARE info */
Node *p_value_substitute; /* what to replace VALUE with, if any */
bool p_hasAggs;
bool p_hasWindowFuncs;
bool p_hasSubLinks;
bool p_hasModifyingCTE;
bool p_is_insert;
bool p_is_update;
bool p_locked_from_parent;
Relation p_target_relation;
RangeTblEntry *p_target_rangetblentry;
/*
* Optional hook functions for parser callbacks. These are null unless
* set up by the caller of make_parsestate.
*/
PreParseColumnRefHook p_pre_columnref_hook;
PostParseColumnRefHook p_post_columnref_hook;
ParseParamRefHook p_paramref_hook;
CoerceParamHook p_coerce_param_hook;
void *p_ref_hook_state; /* common passthrough link for above */
};
/* Support for parser_errposition_callback function */
typedef struct ParseCallbackState
{
ParseState *pstate;
int location;
ErrorContextCallback errcontext;
} ParseCallbackState;
extern ParseState *make_parsestate(ParseState *parentParseState);
extern void free_parsestate(ParseState *pstate);
extern int parser_errposition(ParseState *pstate, int location);
extern void setup_parser_errposition_callback(ParseCallbackState *pcbstate,
ParseState *pstate, int location);
extern void cancel_parser_errposition_callback(ParseCallbackState *pcbstate);
extern Var *make_var(ParseState *pstate, RangeTblEntry *rte, int attrno,
int location);
extern Oid transformArrayType(Oid *arrayType, int32 *arrayTypmod);
extern ArrayRef *transformArraySubscripts(ParseState *pstate,
Node *arrayBase,
Oid arrayType,
Oid elementType,
int32 arrayTypMod,
List *indirection,
Node *assignFrom);
extern Const *make_const(ParseState *pstate, Value *value, int location);
#endif /* PARSE_NODE_H */
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