PostgreSQL Source Code  git master
nodeFuncs.h
Go to the documentation of this file.
1 /*-------------------------------------------------------------------------
2  *
3  * nodeFuncs.h
4  * Various general-purpose manipulations of Node trees
5  *
6  * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  * src/include/nodes/nodeFuncs.h
10  *
11  *-------------------------------------------------------------------------
12  */
13 #ifndef NODEFUNCS_H
14 #define NODEFUNCS_H
15 
16 #include "nodes/parsenodes.h"
17 
18 struct PlanState; /* avoid including execnodes.h too */
19 
20 
21 /* flags bits for query_tree_walker and query_tree_mutator */
22 #define QTW_IGNORE_RT_SUBQUERIES 0x01 /* subqueries in rtable */
23 #define QTW_IGNORE_CTE_SUBQUERIES 0x02 /* subqueries in cteList */
24 #define QTW_IGNORE_RC_SUBQUERIES 0x03 /* both of above */
25 #define QTW_IGNORE_JOINALIASES 0x04 /* JOIN alias var lists */
26 #define QTW_IGNORE_RANGE_TABLE 0x08 /* skip rangetable entirely */
27 #define QTW_EXAMINE_RTES_BEFORE 0x10 /* examine RTE nodes before their
28  * contents */
29 #define QTW_EXAMINE_RTES_AFTER 0x20 /* examine RTE nodes after their
30  * contents */
31 #define QTW_DONT_COPY_QUERY 0x40 /* do not copy top Query */
32 #define QTW_EXAMINE_SORTGROUP 0x80 /* include SortGroupNode lists */
33 
34 /* callback function for check_functions_in_node */
35 typedef bool (*check_function_callback) (Oid func_id, void *context);
36 
37 /* callback functions for tree walkers */
38 typedef bool (*tree_walker_callback) (Node *node, void *context);
39 typedef bool (*planstate_tree_walker_callback) (struct PlanState *planstate,
40  void *context);
41 
42 /* callback functions for tree mutators */
43 typedef Node *(*tree_mutator_callback) (Node *node, void *context);
44 
45 
46 extern Oid exprType(const Node *expr);
47 extern int32 exprTypmod(const Node *expr);
48 extern bool exprIsLengthCoercion(const Node *expr, int32 *coercedTypmod);
49 extern Node *applyRelabelType(Node *arg, Oid rtype, int32 rtypmod, Oid rcollid,
50  CoercionForm rformat, int rlocation,
51  bool overwrite_ok);
52 extern Node *relabel_to_typmod(Node *expr, int32 typmod);
53 extern Node *strip_implicit_coercions(Node *node);
54 extern bool expression_returns_set(Node *clause);
55 
56 extern Oid exprCollation(const Node *expr);
57 extern Oid exprInputCollation(const Node *expr);
58 extern void exprSetCollation(Node *expr, Oid collation);
59 extern void exprSetInputCollation(Node *expr, Oid inputcollation);
60 
61 extern int exprLocation(const Node *expr);
62 
63 extern void fix_opfuncids(Node *node);
64 extern void set_opfuncid(OpExpr *opexpr);
65 extern void set_sa_opfuncid(ScalarArrayOpExpr *opexpr);
66 
67 /* Is clause a FuncExpr clause? */
68 static inline bool
69 is_funcclause(const void *clause)
70 {
71  return clause != NULL && IsA(clause, FuncExpr);
72 }
73 
74 /* Is clause an OpExpr clause? */
75 static inline bool
76 is_opclause(const void *clause)
77 {
78  return clause != NULL && IsA(clause, OpExpr);
79 }
80 
81 /* Extract left arg of a binary opclause, or only arg of a unary opclause */
82 static inline Node *
83 get_leftop(const void *clause)
84 {
85  const OpExpr *expr = (const OpExpr *) clause;
86 
87  if (expr->args != NIL)
88  return (Node *) linitial(expr->args);
89  else
90  return NULL;
91 }
92 
93 /* Extract right arg of a binary opclause (NULL if it's a unary opclause) */
94 static inline Node *
95 get_rightop(const void *clause)
96 {
97  const OpExpr *expr = (const OpExpr *) clause;
98 
99  if (list_length(expr->args) >= 2)
100  return (Node *) lsecond(expr->args);
101  else
102  return NULL;
103 }
104 
105 /* Is clause an AND clause? */
106 static inline bool
107 is_andclause(const void *clause)
108 {
109  return (clause != NULL &&
110  IsA(clause, BoolExpr) &&
111  ((const BoolExpr *) clause)->boolop == AND_EXPR);
112 }
113 
114 /* Is clause an OR clause? */
115 static inline bool
116 is_orclause(const void *clause)
117 {
118  return (clause != NULL &&
119  IsA(clause, BoolExpr) &&
120  ((const BoolExpr *) clause)->boolop == OR_EXPR);
121 }
122 
123 /* Is clause a NOT clause? */
124 static inline bool
125 is_notclause(const void *clause)
126 {
127  return (clause != NULL &&
128  IsA(clause, BoolExpr) &&
129  ((const BoolExpr *) clause)->boolop == NOT_EXPR);
130 }
131 
132 /* Extract argument from a clause known to be a NOT clause */
133 static inline Expr *
134 get_notclausearg(const void *notclause)
135 {
136  return (Expr *) linitial(((const BoolExpr *) notclause)->args);
137 }
138 
139 extern bool check_functions_in_node(Node *node, check_function_callback checker,
140  void *context);
141 
142 /*
143  * The following functions are usually passed walker or mutator callbacks
144  * that are declared like "bool walker(Node *node, my_struct *context)"
145  * rather than "bool walker(Node *node, void *context)" as a strict reading
146  * of the C standard would require. Changing the callbacks' declarations
147  * to "void *" would create serious hazards of passing them the wrong context
148  * struct type, so we respectfully decline to support the standard's position
149  * that a pointer to struct is incompatible with "void *". Instead, silence
150  * related compiler warnings by inserting casts into these macro wrappers.
151  */
152 
153 #define expression_tree_walker(n, w, c) \
154  expression_tree_walker_impl(n, (tree_walker_callback) (w), c)
155 #define expression_tree_mutator(n, m, c) \
156  expression_tree_mutator_impl(n, (tree_mutator_callback) (m), c)
157 
158 #define query_tree_walker(q, w, c, f) \
159  query_tree_walker_impl(q, (tree_walker_callback) (w), c, f)
160 #define query_tree_mutator(q, m, c, f) \
161  query_tree_mutator_impl(q, (tree_mutator_callback) (m), c, f)
162 
163 #define range_table_walker(rt, w, c, f) \
164  range_table_walker_impl(rt, (tree_walker_callback) (w), c, f)
165 #define range_table_mutator(rt, m, c, f) \
166  range_table_mutator_impl(rt, (tree_mutator_callback) (m), c, f)
167 
168 #define range_table_entry_walker(r, w, c, f) \
169  range_table_entry_walker_impl(r, (tree_walker_callback) (w), c, f)
170 
171 #define query_or_expression_tree_walker(n, w, c, f) \
172  query_or_expression_tree_walker_impl(n, (tree_walker_callback) (w), c, f)
173 #define query_or_expression_tree_mutator(n, m, c, f) \
174  query_or_expression_tree_mutator_impl(n, (tree_mutator_callback) (m), c, f)
175 
176 #define raw_expression_tree_walker(n, w, c) \
177  raw_expression_tree_walker_impl(n, (tree_walker_callback) (w), c)
178 
179 #define planstate_tree_walker(ps, w, c) \
180  planstate_tree_walker_impl(ps, (planstate_tree_walker_callback) (w), c)
181 
182 extern bool expression_tree_walker_impl(Node *node,
183  tree_walker_callback walker,
184  void *context);
186  tree_mutator_callback mutator,
187  void *context);
188 
189 extern bool query_tree_walker_impl(Query *query,
190  tree_walker_callback walker,
191  void *context, int flags);
192 extern Query *query_tree_mutator_impl(Query *query,
193  tree_mutator_callback mutator,
194  void *context, int flags);
195 
196 extern bool range_table_walker_impl(List *rtable,
197  tree_walker_callback walker,
198  void *context, int flags);
199 extern List *range_table_mutator_impl(List *rtable,
200  tree_mutator_callback mutator,
201  void *context, int flags);
202 
204  tree_walker_callback walker,
205  void *context, int flags);
206 
208  tree_walker_callback walker,
209  void *context, int flags);
211  tree_mutator_callback mutator,
212  void *context, int flags);
213 
214 extern bool raw_expression_tree_walker_impl(Node *node,
215  tree_walker_callback walker,
216  void *context);
217 
218 extern bool planstate_tree_walker_impl(struct PlanState *planstate,
220  void *context);
221 
222 #endif /* NODEFUNCS_H */
Datum boolop(PG_FUNCTION_ARGS)
Definition: _int_bool.c:418
signed int int32
Definition: c.h:430
unsigned char bool
Definition: c.h:392
bool query_tree_walker_impl(Query *query, tree_walker_callback walker, void *context, int flags)
Definition: nodeFuncs.c:2364
static bool is_andclause(const void *clause)
Definition: nodeFuncs.h:105
bool raw_expression_tree_walker_impl(Node *node, tree_walker_callback walker, void *context)
Definition: nodeFuncs.c:3552
static Expr * get_notclausearg(const void *notclause)
Definition: nodeFuncs.h:132
static bool is_orclause(const void *clause)
Definition: nodeFuncs.h:114
Node * query_or_expression_tree_mutator_impl(Node *node, tree_mutator_callback mutator, void *context, int flags)
Definition: nodeFuncs.c:3521
Oid exprType(const Node *expr)
Definition: nodeFuncs.c:43
bool(* planstate_tree_walker_callback)(struct PlanState *planstate, void *context)
Definition: nodeFuncs.h:37
bool planstate_tree_walker_impl(struct PlanState *planstate, planstate_tree_walker_callback walker, void *context)
Definition: nodeFuncs.c:4057
bool range_table_entry_walker_impl(RangeTblEntry *rte, tree_walker_callback walker, void *context, int flags)
Definition: nodeFuncs.c:2486
Query * query_tree_mutator_impl(Query *query, tree_mutator_callback mutator, void *context, int flags)
Definition: nodeFuncs.c:3339
bool exprIsLengthCoercion(const Node *expr, int32 *coercedTypmod)
Definition: nodeFuncs.c:500
void exprSetCollation(Node *expr, Oid collation)
Definition: nodeFuncs.c:1020
Oid exprInputCollation(const Node *expr)
Definition: nodeFuncs.c:972
Node * expression_tree_mutator_impl(Node *node, tree_mutator_callback mutator, void *context)
Definition: nodeFuncs.c:2609
static bool is_opclause(const void *clause)
Definition: nodeFuncs.h:74
bool(* tree_walker_callback)(Node *node, void *context)
Definition: nodeFuncs.h:36
static Node * get_rightop(const void *clause)
Definition: nodeFuncs.h:93
int32 exprTypmod(const Node *expr)
Definition: nodeFuncs.c:266
bool check_functions_in_node(Node *node, check_function_callback checker, void *context)
Definition: nodeFuncs.c:1710
Oid exprCollation(const Node *expr)
Definition: nodeFuncs.c:764
Node *(* tree_mutator_callback)(Node *node, void *context)
Definition: nodeFuncs.h:41
void exprSetInputCollation(Node *expr, Oid inputcollation)
Definition: nodeFuncs.c:1179
bool query_or_expression_tree_walker_impl(Node *node, tree_walker_callback walker, void *context, int flags)
Definition: nodeFuncs.c:3498
List * range_table_mutator_impl(List *rtable, tree_mutator_callback mutator, void *context, int flags)
Definition: nodeFuncs.c:3429
Node * applyRelabelType(Node *arg, Oid rtype, int32 rtypmod, Oid rcollid, CoercionForm rformat, int rlocation, bool overwrite_ok)
Definition: nodeFuncs.c:579
bool expression_tree_walker_impl(Node *node, tree_walker_callback walker, void *context)
Definition: nodeFuncs.c:1893
static bool is_funcclause(const void *clause)
Definition: nodeFuncs.h:67
bool range_table_walker_impl(List *rtable, tree_walker_callback walker, void *context, int flags)
Definition: nodeFuncs.c:2465
static bool is_notclause(const void *clause)
Definition: nodeFuncs.h:123
bool(* check_function_callback)(Oid func_id, void *context)
Definition: nodeFuncs.h:33
Node * relabel_to_typmod(Node *expr, int32 typmod)
Definition: nodeFuncs.c:632
int exprLocation(const Node *expr)
Definition: nodeFuncs.c:1243
Node * strip_implicit_coercions(Node *node)
Definition: nodeFuncs.c:648
bool expression_returns_set(Node *clause)
Definition: nodeFuncs.c:706
void fix_opfuncids(Node *node)
Definition: nodeFuncs.c:1641
static Node * get_leftop(const void *clause)
Definition: nodeFuncs.h:81
void set_sa_opfuncid(ScalarArrayOpExpr *opexpr)
Definition: nodeFuncs.c:1683
void set_opfuncid(OpExpr *opexpr)
Definition: nodeFuncs.c:1672
#define IsA(nodeptr, _type_)
Definition: nodes.h:168
void * arg
static int list_length(const List *l)
Definition: pg_list.h:150
#define NIL
Definition: pg_list.h:66
#define linitial(l)
Definition: pg_list.h:176
#define lsecond(l)
Definition: pg_list.h:181
unsigned int Oid
Definition: postgres_ext.h:31
@ AND_EXPR
Definition: primnodes.h:758
@ OR_EXPR
Definition: primnodes.h:758
@ NOT_EXPR
Definition: primnodes.h:758
CoercionForm
Definition: primnodes.h:585
Definition: pg_list.h:52
Definition: nodes.h:118
List * args
Definition: primnodes.h:666