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pg_list.h
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1 /*-------------------------------------------------------------------------
2  *
3  * pg_list.h
4  * interface for PostgreSQL generic list package
5  *
6  * Once upon a time, parts of Postgres were written in Lisp and used real
7  * cons-cell lists for major data structures. When that code was rewritten
8  * in C, we initially had a faithful emulation of cons-cell lists, which
9  * unsurprisingly was a performance bottleneck. A couple of major rewrites
10  * later, these data structures are actually simple expansible arrays;
11  * but the "List" name and a lot of the notation survives.
12  *
13  * One important concession to the original implementation is that an empty
14  * list is always represented by a null pointer (preferentially written NIL).
15  * Non-empty lists have a header, which will not be relocated as long as the
16  * list remains non-empty, and an expansible data array.
17  *
18  * We support four types of lists:
19  *
20  * T_List: lists of pointers
21  * (in practice usually pointers to Nodes, but not always;
22  * declared as "void *" to minimize casting annoyances)
23  * T_IntList: lists of integers
24  * T_OidList: lists of Oids
25  * T_XidList: lists of TransactionIds
26  * (the XidList infrastructure is less complete than the other cases)
27  *
28  * (At the moment, ints, Oids, and XIDs are the same size, but they may not
29  * always be so; be careful to use the appropriate list type for your data.)
30  *
31  *
32  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
33  * Portions Copyright (c) 1994, Regents of the University of California
34  *
35  * src/include/nodes/pg_list.h
36  *
37  *-------------------------------------------------------------------------
38  */
39 #ifndef PG_LIST_H
40 #define PG_LIST_H
41 
42 #include "nodes/nodes.h"
43 
44 
45 typedef union ListCell
46 {
47  void *ptr_value;
48  int int_value;
52 
53 typedef struct List
54 {
55  NodeTag type; /* T_List, T_IntList, T_OidList, or T_XidList */
56  int length; /* number of elements currently present */
57  int max_length; /* allocated length of elements[] */
58  ListCell *elements; /* re-allocatable array of cells */
59  /* We may allocate some cells along with the List header: */
61  /* If elements == initial_elements, it's not a separate allocation */
62 } List;
63 
64 /*
65  * The *only* valid representation of an empty list is NIL; in other
66  * words, a non-NIL list is guaranteed to have length >= 1.
67  */
68 #define NIL ((List *) NULL)
69 
70 /*
71  * State structs for various looping macros below.
72  */
73 typedef struct ForEachState
74 {
75  const List *l; /* list we're looping through */
76  int i; /* current element index */
78 
79 typedef struct ForBothState
80 {
81  const List *l1; /* lists we're looping through */
82  const List *l2;
83  int i; /* common element index */
85 
86 typedef struct ForBothCellState
87 {
88  const List *l1; /* lists we're looping through */
89  const List *l2;
90  int i1; /* current element indexes */
91  int i2;
93 
94 typedef struct ForThreeState
95 {
96  const List *l1; /* lists we're looping through */
97  const List *l2;
98  const List *l3;
99  int i; /* common element index */
101 
102 typedef struct ForFourState
103 {
104  const List *l1; /* lists we're looping through */
105  const List *l2;
106  const List *l3;
107  const List *l4;
108  int i; /* common element index */
110 
111 typedef struct ForFiveState
112 {
113  const List *l1; /* lists we're looping through */
114  const List *l2;
115  const List *l3;
116  const List *l4;
117  const List *l5;
118  int i; /* common element index */
120 
121 /*
122  * These routines are small enough, and used often enough, to justify being
123  * inline.
124  */
125 
126 /* Fetch address of list's first cell; NULL if empty list */
127 static inline ListCell *
128 list_head(const List *l)
129 {
130  return l ? &l->elements[0] : NULL;
131 }
132 
133 /* Fetch address of list's last cell; NULL if empty list */
134 static inline ListCell *
135 list_tail(const List *l)
136 {
137  return l ? &l->elements[l->length - 1] : NULL;
138 }
139 
140 /* Fetch address of list's second cell, if it has one, else NULL */
141 static inline ListCell *
143 {
144  if (l && l->length >= 2)
145  return &l->elements[1];
146  else
147  return NULL;
148 }
149 
150 /* Fetch list's length */
151 static inline int
152 list_length(const List *l)
153 {
154  return l ? l->length : 0;
155 }
156 
157 /*
158  * Macros to access the data values within List cells.
159  *
160  * Note that with the exception of the "xxx_node" macros, these are
161  * lvalues and can be assigned to.
162  *
163  * NB: There is an unfortunate legacy from a previous incarnation of
164  * the List API: the macro lfirst() was used to mean "the data in this
165  * cons cell". To avoid changing every usage of lfirst(), that meaning
166  * has been kept. As a result, lfirst() takes a ListCell and returns
167  * the data it contains; to get the data in the first cell of a
168  * List, use linitial(). Worse, lsecond() is more closely related to
169  * linitial() than lfirst(): given a List, lsecond() returns the data
170  * in the second list cell.
171  */
172 #define lfirst(lc) ((lc)->ptr_value)
173 #define lfirst_int(lc) ((lc)->int_value)
174 #define lfirst_oid(lc) ((lc)->oid_value)
175 #define lfirst_xid(lc) ((lc)->xid_value)
176 #define lfirst_node(type,lc) castNode(type, lfirst(lc))
177 
178 #define linitial(l) lfirst(list_nth_cell(l, 0))
179 #define linitial_int(l) lfirst_int(list_nth_cell(l, 0))
180 #define linitial_oid(l) lfirst_oid(list_nth_cell(l, 0))
181 #define linitial_node(type,l) castNode(type, linitial(l))
182 
183 #define lsecond(l) lfirst(list_nth_cell(l, 1))
184 #define lsecond_int(l) lfirst_int(list_nth_cell(l, 1))
185 #define lsecond_oid(l) lfirst_oid(list_nth_cell(l, 1))
186 #define lsecond_node(type,l) castNode(type, lsecond(l))
187 
188 #define lthird(l) lfirst(list_nth_cell(l, 2))
189 #define lthird_int(l) lfirst_int(list_nth_cell(l, 2))
190 #define lthird_oid(l) lfirst_oid(list_nth_cell(l, 2))
191 #define lthird_node(type,l) castNode(type, lthird(l))
192 
193 #define lfourth(l) lfirst(list_nth_cell(l, 3))
194 #define lfourth_int(l) lfirst_int(list_nth_cell(l, 3))
195 #define lfourth_oid(l) lfirst_oid(list_nth_cell(l, 3))
196 #define lfourth_node(type,l) castNode(type, lfourth(l))
197 
198 #define llast(l) lfirst(list_last_cell(l))
199 #define llast_int(l) lfirst_int(list_last_cell(l))
200 #define llast_oid(l) lfirst_oid(list_last_cell(l))
201 #define llast_xid(l) lfirst_xid(list_last_cell(l))
202 #define llast_node(type,l) castNode(type, llast(l))
203 
204 /*
205  * Convenience macros for building fixed-length lists
206  */
207 #define list_make_ptr_cell(v) ((ListCell) {.ptr_value = (v)})
208 #define list_make_int_cell(v) ((ListCell) {.int_value = (v)})
209 #define list_make_oid_cell(v) ((ListCell) {.oid_value = (v)})
210 #define list_make_xid_cell(v) ((ListCell) {.xid_value = (v)})
211 
212 #define list_make1(x1) \
213  list_make1_impl(T_List, list_make_ptr_cell(x1))
214 #define list_make2(x1,x2) \
215  list_make2_impl(T_List, list_make_ptr_cell(x1), list_make_ptr_cell(x2))
216 #define list_make3(x1,x2,x3) \
217  list_make3_impl(T_List, list_make_ptr_cell(x1), list_make_ptr_cell(x2), \
218  list_make_ptr_cell(x3))
219 #define list_make4(x1,x2,x3,x4) \
220  list_make4_impl(T_List, list_make_ptr_cell(x1), list_make_ptr_cell(x2), \
221  list_make_ptr_cell(x3), list_make_ptr_cell(x4))
222 #define list_make5(x1,x2,x3,x4,x5) \
223  list_make5_impl(T_List, list_make_ptr_cell(x1), list_make_ptr_cell(x2), \
224  list_make_ptr_cell(x3), list_make_ptr_cell(x4), \
225  list_make_ptr_cell(x5))
226 
227 #define list_make1_int(x1) \
228  list_make1_impl(T_IntList, list_make_int_cell(x1))
229 #define list_make2_int(x1,x2) \
230  list_make2_impl(T_IntList, list_make_int_cell(x1), list_make_int_cell(x2))
231 #define list_make3_int(x1,x2,x3) \
232  list_make3_impl(T_IntList, list_make_int_cell(x1), list_make_int_cell(x2), \
233  list_make_int_cell(x3))
234 #define list_make4_int(x1,x2,x3,x4) \
235  list_make4_impl(T_IntList, list_make_int_cell(x1), list_make_int_cell(x2), \
236  list_make_int_cell(x3), list_make_int_cell(x4))
237 #define list_make5_int(x1,x2,x3,x4,x5) \
238  list_make5_impl(T_IntList, list_make_int_cell(x1), list_make_int_cell(x2), \
239  list_make_int_cell(x3), list_make_int_cell(x4), \
240  list_make_int_cell(x5))
241 
242 #define list_make1_oid(x1) \
243  list_make1_impl(T_OidList, list_make_oid_cell(x1))
244 #define list_make2_oid(x1,x2) \
245  list_make2_impl(T_OidList, list_make_oid_cell(x1), list_make_oid_cell(x2))
246 #define list_make3_oid(x1,x2,x3) \
247  list_make3_impl(T_OidList, list_make_oid_cell(x1), list_make_oid_cell(x2), \
248  list_make_oid_cell(x3))
249 #define list_make4_oid(x1,x2,x3,x4) \
250  list_make4_impl(T_OidList, list_make_oid_cell(x1), list_make_oid_cell(x2), \
251  list_make_oid_cell(x3), list_make_oid_cell(x4))
252 #define list_make5_oid(x1,x2,x3,x4,x5) \
253  list_make5_impl(T_OidList, list_make_oid_cell(x1), list_make_oid_cell(x2), \
254  list_make_oid_cell(x3), list_make_oid_cell(x4), \
255  list_make_oid_cell(x5))
256 
257 #define list_make1_xid(x1) \
258  list_make1_impl(T_XidList, list_make_xid_cell(x1))
259 #define list_make2_xid(x1,x2) \
260  list_make2_impl(T_XidList, list_make_xid_cell(x1), list_make_xid_cell(x2))
261 #define list_make3_xid(x1,x2,x3) \
262  list_make3_impl(T_XidList, list_make_xid_cell(x1), list_make_xid_cell(x2), \
263  list_make_xid_cell(x3))
264 #define list_make4_xid(x1,x2,x3,x4) \
265  list_make4_impl(T_XidList, list_make_xid_cell(x1), list_make_xid_cell(x2), \
266  list_make_xid_cell(x3), list_make_xid_cell(x4))
267 #define list_make5_xid(x1,x2,x3,x4,x5) \
268  list_make5_impl(T_XidList, list_make_xid_cell(x1), list_make_xid_cell(x2), \
269  list_make_xid_cell(x3), list_make_xid_cell(x4), \
270  list_make_xid_cell(x5))
271 
272 /*
273  * Locate the n'th cell (counting from 0) of the list.
274  * It is an assertion failure if there is no such cell.
275  */
276 static inline ListCell *
277 list_nth_cell(const List *list, int n)
278 {
279  Assert(list != NIL);
280  Assert(n >= 0 && n < list->length);
281  return &list->elements[n];
282 }
283 
284 /*
285  * Return the last cell in a non-NIL List.
286  */
287 static inline ListCell *
289 {
290  Assert(list != NIL);
291  return &list->elements[list->length - 1];
292 }
293 
294 /*
295  * Return the pointer value contained in the n'th element of the
296  * specified list. (List elements begin at 0.)
297  */
298 static inline void *
299 list_nth(const List *list, int n)
300 {
301  Assert(IsA(list, List));
302  return lfirst(list_nth_cell(list, n));
303 }
304 
305 /*
306  * Return the integer value contained in the n'th element of the
307  * specified list.
308  */
309 static inline int
310 list_nth_int(const List *list, int n)
311 {
312  Assert(IsA(list, IntList));
313  return lfirst_int(list_nth_cell(list, n));
314 }
315 
316 /*
317  * Return the OID value contained in the n'th element of the specified
318  * list.
319  */
320 static inline Oid
321 list_nth_oid(const List *list, int n)
322 {
323  Assert(IsA(list, OidList));
324  return lfirst_oid(list_nth_cell(list, n));
325 }
326 
327 #define list_nth_node(type,list,n) castNode(type, list_nth(list, n))
328 
329 /*
330  * Get the given ListCell's index (from 0) in the given List.
331  */
332 static inline int
333 list_cell_number(const List *l, const ListCell *c)
334 {
335  Assert(c >= &l->elements[0] && c < &l->elements[l->length]);
336  return c - l->elements;
337 }
338 
339 /*
340  * Get the address of the next cell after "c" within list "l", or NULL if none.
341  */
342 static inline ListCell *
343 lnext(const List *l, const ListCell *c)
344 {
345  Assert(c >= &l->elements[0] && c < &l->elements[l->length]);
346  c++;
347  if (c < &l->elements[l->length])
348  return (ListCell *) c;
349  else
350  return NULL;
351 }
352 
353 /*
354  * foreach -
355  * a convenience macro for looping through a list
356  *
357  * "cell" must be the name of a "ListCell *" variable; it's made to point
358  * to each List element in turn. "cell" will be NULL after normal exit from
359  * the loop, but an early "break" will leave it pointing at the current
360  * List element.
361  *
362  * Beware of changing the List object while the loop is iterating.
363  * The current semantics are that we examine successive list indices in
364  * each iteration, so that insertion or deletion of list elements could
365  * cause elements to be re-visited or skipped unexpectedly. Previous
366  * implementations of foreach() behaved differently. However, it's safe
367  * to append elements to the List (or in general, insert them after the
368  * current element); such new elements are guaranteed to be visited.
369  * Also, the current element of the List can be deleted, if you use
370  * foreach_delete_current() to do so. BUT: either of these actions will
371  * invalidate the "cell" pointer for the remainder of the current iteration.
372  */
373 #define foreach(cell, lst) \
374  for (ForEachState cell##__state = {(lst), 0}; \
375  (cell##__state.l != NIL && \
376  cell##__state.i < cell##__state.l->length) ? \
377  (cell = &cell##__state.l->elements[cell##__state.i], true) : \
378  (cell = NULL, false); \
379  cell##__state.i++)
380 
381 /*
382  * foreach_delete_current -
383  * delete the current list element from the List associated with a
384  * surrounding foreach() or foreach_*() loop, returning the new List
385  * pointer; pass the name of the iterator variable.
386  *
387  * This is similar to list_delete_cell(), but it also adjusts the loop's state
388  * so that no list elements will be missed. Do not delete elements from an
389  * active foreach or foreach_* loop's list in any other way!
390  */
391 #define foreach_delete_current(lst, var_or_cell) \
392  ((List *) (var_or_cell##__state.l = list_delete_nth_cell(lst, var_or_cell##__state.i--)))
393 
394 /*
395  * foreach_current_index -
396  * get the zero-based list index of a surrounding foreach() or foreach_*()
397  * loop's current element; pass the name of the iterator variable.
398  *
399  * Beware of using this after foreach_delete_current(); the value will be
400  * out of sync for the rest of the current loop iteration. Anyway, since
401  * you just deleted the current element, the value is pretty meaningless.
402  */
403 #define foreach_current_index(var_or_cell) (var_or_cell##__state.i)
404 
405 /*
406  * for_each_from -
407  * Like foreach(), but start from the N'th (zero-based) list element,
408  * not necessarily the first one.
409  *
410  * It's okay for N to exceed the list length, but not for it to be negative.
411  *
412  * The caveats for foreach() apply equally here.
413  */
414 #define for_each_from(cell, lst, N) \
415  for (ForEachState cell##__state = for_each_from_setup(lst, N); \
416  (cell##__state.l != NIL && \
417  cell##__state.i < cell##__state.l->length) ? \
418  (cell = &cell##__state.l->elements[cell##__state.i], true) : \
419  (cell = NULL, false); \
420  cell##__state.i++)
421 
422 static inline ForEachState
423 for_each_from_setup(const List *lst, int N)
424 {
425  ForEachState r = {lst, N};
426 
427  Assert(N >= 0);
428  return r;
429 }
430 
431 /*
432  * for_each_cell -
433  * a convenience macro which loops through a list starting from a
434  * specified cell
435  *
436  * The caveats for foreach() apply equally here.
437  */
438 #define for_each_cell(cell, lst, initcell) \
439  for (ForEachState cell##__state = for_each_cell_setup(lst, initcell); \
440  (cell##__state.l != NIL && \
441  cell##__state.i < cell##__state.l->length) ? \
442  (cell = &cell##__state.l->elements[cell##__state.i], true) : \
443  (cell = NULL, false); \
444  cell##__state.i++)
445 
446 static inline ForEachState
447 for_each_cell_setup(const List *lst, const ListCell *initcell)
448 {
449  ForEachState r = {lst,
450  initcell ? list_cell_number(lst, initcell) : list_length(lst)};
451 
452  return r;
453 }
454 
455 /*
456  * Convenience macros that loop through a list without needing a separate
457  * "ListCell *" variable. Instead, the macros declare a locally-scoped loop
458  * variable with the provided name and the appropriate type.
459  *
460  * Since the variable is scoped to the loop, it's not possible to detect an
461  * early break by checking its value after the loop completes, as is common
462  * practice. If you need to do this, you can either use foreach() instead or
463  * manually track early breaks with a separate variable declared outside of the
464  * loop.
465  *
466  * Note that the caveats described in the comment above the foreach() macro
467  * also apply to these convenience macros.
468  */
469 #define foreach_ptr(type, var, lst) foreach_internal(type, *, var, lst, lfirst)
470 #define foreach_int(var, lst) foreach_internal(int, , var, lst, lfirst_int)
471 #define foreach_oid(var, lst) foreach_internal(Oid, , var, lst, lfirst_oid)
472 #define foreach_xid(var, lst) foreach_internal(TransactionId, , var, lst, lfirst_xid)
473 
474 /*
475  * The internal implementation of the above macros. Do not use directly.
476  *
477  * This macro actually generates two loops in order to declare two variables of
478  * different types. The outer loop only iterates once, so we expect optimizing
479  * compilers will unroll it, thereby optimizing it away.
480  */
481 #define foreach_internal(type, pointer, var, lst, func) \
482  for (type pointer var = 0, pointer var##__outerloop = (type pointer) 1; \
483  var##__outerloop; \
484  var##__outerloop = 0) \
485  for (ForEachState var##__state = {(lst), 0}; \
486  (var##__state.l != NIL && \
487  var##__state.i < var##__state.l->length && \
488  (var = func(&var##__state.l->elements[var##__state.i]), true)); \
489  var##__state.i++)
490 
491 /*
492  * foreach_node -
493  * The same as foreach_ptr, but asserts that the element is of the specified
494  * node type.
495  */
496 #define foreach_node(type, var, lst) \
497  for (type * var = 0, *var##__outerloop = (type *) 1; \
498  var##__outerloop; \
499  var##__outerloop = 0) \
500  for (ForEachState var##__state = {(lst), 0}; \
501  (var##__state.l != NIL && \
502  var##__state.i < var##__state.l->length && \
503  (var = lfirst_node(type, &var##__state.l->elements[var##__state.i]), true)); \
504  var##__state.i++)
505 
506 /*
507  * forboth -
508  * a convenience macro for advancing through two linked lists
509  * simultaneously. This macro loops through both lists at the same
510  * time, stopping when either list runs out of elements. Depending
511  * on the requirements of the call site, it may also be wise to
512  * assert that the lengths of the two lists are equal. (But, if they
513  * are not, some callers rely on the ending cell values being separately
514  * NULL or non-NULL as defined here; don't try to optimize that.)
515  *
516  * The caveats for foreach() apply equally here.
517  */
518 #define forboth(cell1, list1, cell2, list2) \
519  for (ForBothState cell1##__state = {(list1), (list2), 0}; \
520  multi_for_advance_cell(cell1, cell1##__state, l1, i), \
521  multi_for_advance_cell(cell2, cell1##__state, l2, i), \
522  (cell1 != NULL && cell2 != NULL); \
523  cell1##__state.i++)
524 
525 #define multi_for_advance_cell(cell, state, l, i) \
526  (cell = (state.l != NIL && state.i < state.l->length) ? \
527  &state.l->elements[state.i] : NULL)
528 
529 /*
530  * for_both_cell -
531  * a convenience macro which loops through two lists starting from the
532  * specified cells of each. This macro loops through both lists at the same
533  * time, stopping when either list runs out of elements. Depending on the
534  * requirements of the call site, it may also be wise to assert that the
535  * lengths of the two lists are equal, and initcell1 and initcell2 are at
536  * the same position in the respective lists.
537  *
538  * The caveats for foreach() apply equally here.
539  */
540 #define for_both_cell(cell1, list1, initcell1, cell2, list2, initcell2) \
541  for (ForBothCellState cell1##__state = \
542  for_both_cell_setup(list1, initcell1, list2, initcell2); \
543  multi_for_advance_cell(cell1, cell1##__state, l1, i1), \
544  multi_for_advance_cell(cell2, cell1##__state, l2, i2), \
545  (cell1 != NULL && cell2 != NULL); \
546  cell1##__state.i1++, cell1##__state.i2++)
547 
548 static inline ForBothCellState
549 for_both_cell_setup(const List *list1, const ListCell *initcell1,
550  const List *list2, const ListCell *initcell2)
551 {
552  ForBothCellState r = {list1, list2,
553  initcell1 ? list_cell_number(list1, initcell1) : list_length(list1),
554  initcell2 ? list_cell_number(list2, initcell2) : list_length(list2)};
555 
556  return r;
557 }
558 
559 /*
560  * forthree -
561  * the same for three lists
562  */
563 #define forthree(cell1, list1, cell2, list2, cell3, list3) \
564  for (ForThreeState cell1##__state = {(list1), (list2), (list3), 0}; \
565  multi_for_advance_cell(cell1, cell1##__state, l1, i), \
566  multi_for_advance_cell(cell2, cell1##__state, l2, i), \
567  multi_for_advance_cell(cell3, cell1##__state, l3, i), \
568  (cell1 != NULL && cell2 != NULL && cell3 != NULL); \
569  cell1##__state.i++)
570 
571 /*
572  * forfour -
573  * the same for four lists
574  */
575 #define forfour(cell1, list1, cell2, list2, cell3, list3, cell4, list4) \
576  for (ForFourState cell1##__state = {(list1), (list2), (list3), (list4), 0}; \
577  multi_for_advance_cell(cell1, cell1##__state, l1, i), \
578  multi_for_advance_cell(cell2, cell1##__state, l2, i), \
579  multi_for_advance_cell(cell3, cell1##__state, l3, i), \
580  multi_for_advance_cell(cell4, cell1##__state, l4, i), \
581  (cell1 != NULL && cell2 != NULL && cell3 != NULL && cell4 != NULL); \
582  cell1##__state.i++)
583 
584 /*
585  * forfive -
586  * the same for five lists
587  */
588 #define forfive(cell1, list1, cell2, list2, cell3, list3, cell4, list4, cell5, list5) \
589  for (ForFiveState cell1##__state = {(list1), (list2), (list3), (list4), (list5), 0}; \
590  multi_for_advance_cell(cell1, cell1##__state, l1, i), \
591  multi_for_advance_cell(cell2, cell1##__state, l2, i), \
592  multi_for_advance_cell(cell3, cell1##__state, l3, i), \
593  multi_for_advance_cell(cell4, cell1##__state, l4, i), \
594  multi_for_advance_cell(cell5, cell1##__state, l5, i), \
595  (cell1 != NULL && cell2 != NULL && cell3 != NULL && \
596  cell4 != NULL && cell5 != NULL); \
597  cell1##__state.i++)
598 
599 /* Functions in src/backend/nodes/list.c */
600 
601 extern List *list_make1_impl(NodeTag t, ListCell datum1);
602 extern List *list_make2_impl(NodeTag t, ListCell datum1, ListCell datum2);
603 extern List *list_make3_impl(NodeTag t, ListCell datum1, ListCell datum2,
604  ListCell datum3);
605 extern List *list_make4_impl(NodeTag t, ListCell datum1, ListCell datum2,
606  ListCell datum3, ListCell datum4);
607 extern List *list_make5_impl(NodeTag t, ListCell datum1, ListCell datum2,
608  ListCell datum3, ListCell datum4,
609  ListCell datum5);
610 
611 extern pg_nodiscard List *lappend(List *list, void *datum);
612 extern pg_nodiscard List *lappend_int(List *list, int datum);
613 extern pg_nodiscard List *lappend_oid(List *list, Oid datum);
615 
616 extern pg_nodiscard List *list_insert_nth(List *list, int pos, void *datum);
617 extern pg_nodiscard List *list_insert_nth_int(List *list, int pos, int datum);
618 extern pg_nodiscard List *list_insert_nth_oid(List *list, int pos, Oid datum);
619 
620 extern pg_nodiscard List *lcons(void *datum, List *list);
621 extern pg_nodiscard List *lcons_int(int datum, List *list);
622 extern pg_nodiscard List *lcons_oid(Oid datum, List *list);
623 
624 extern pg_nodiscard List *list_concat(List *list1, const List *list2);
625 extern pg_nodiscard List *list_concat_copy(const List *list1, const List *list2);
626 
627 extern pg_nodiscard List *list_truncate(List *list, int new_size);
628 
629 extern bool list_member(const List *list, const void *datum);
630 extern bool list_member_ptr(const List *list, const void *datum);
631 extern bool list_member_int(const List *list, int datum);
632 extern bool list_member_oid(const List *list, Oid datum);
633 extern bool list_member_xid(const List *list, TransactionId datum);
634 
635 extern pg_nodiscard List *list_delete(List *list, void *datum);
636 extern pg_nodiscard List *list_delete_ptr(List *list, void *datum);
637 extern pg_nodiscard List *list_delete_int(List *list, int datum);
638 extern pg_nodiscard List *list_delete_oid(List *list, Oid datum);
644 
645 extern List *list_union(const List *list1, const List *list2);
646 extern List *list_union_ptr(const List *list1, const List *list2);
647 extern List *list_union_int(const List *list1, const List *list2);
648 extern List *list_union_oid(const List *list1, const List *list2);
649 
650 extern List *list_intersection(const List *list1, const List *list2);
651 extern List *list_intersection_int(const List *list1, const List *list2);
652 
653 /* currently, there's no need for list_intersection_ptr etc */
654 
655 extern List *list_difference(const List *list1, const List *list2);
656 extern List *list_difference_ptr(const List *list1, const List *list2);
657 extern List *list_difference_int(const List *list1, const List *list2);
658 extern List *list_difference_oid(const List *list1, const List *list2);
659 
660 extern pg_nodiscard List *list_append_unique(List *list, void *datum);
661 extern pg_nodiscard List *list_append_unique_ptr(List *list, void *datum);
662 extern pg_nodiscard List *list_append_unique_int(List *list, int datum);
664 
665 extern pg_nodiscard List *list_concat_unique(List *list1, const List *list2);
666 extern pg_nodiscard List *list_concat_unique_ptr(List *list1, const List *list2);
667 extern pg_nodiscard List *list_concat_unique_int(List *list1, const List *list2);
668 extern pg_nodiscard List *list_concat_unique_oid(List *list1, const List *list2);
669 
670 extern void list_deduplicate_oid(List *list);
671 
672 extern void list_free(List *list);
673 extern void list_free_deep(List *list);
674 
675 extern pg_nodiscard List *list_copy(const List *oldlist);
676 extern pg_nodiscard List *list_copy_head(const List *oldlist, int len);
677 extern pg_nodiscard List *list_copy_tail(const List *oldlist, int nskip);
678 extern pg_nodiscard List *list_copy_deep(const List *oldlist);
679 
680 typedef int (*list_sort_comparator) (const ListCell *a, const ListCell *b);
682 
683 extern int list_int_cmp(const ListCell *p1, const ListCell *p2);
684 extern int list_oid_cmp(const ListCell *p1, const ListCell *p2);
685 
686 #endif /* PG_LIST_H */
#define pg_nodiscard
Definition: c.h:135
#define FLEXIBLE_ARRAY_MEMBER
Definition: c.h:385
uint32 TransactionId
Definition: c.h:639
int b
Definition: isn.c:70
int a
Definition: isn.c:69
Assert(fmt[strlen(fmt) - 1] !='\n')
#define IsA(nodeptr, _type_)
Definition: nodes.h:158
NodeTag
Definition: nodes.h:27
const void size_t len
#define lfirst(lc)
Definition: pg_list.h:172
List * list_make5_impl(NodeTag t, ListCell datum1, ListCell datum2, ListCell datum3, ListCell datum4, ListCell datum5)
Definition: list.c:284
pg_nodiscard List * list_copy_head(const List *oldlist, int len)
Definition: list.c:1593
void list_sort(List *list, list_sort_comparator cmp)
Definition: list.c:1674
static int list_length(const List *l)
Definition: pg_list.h:152
pg_nodiscard List * list_copy_deep(const List *oldlist)
Definition: list.c:1639
pg_nodiscard List * lcons_int(int datum, List *list)
Definition: list.c:513
pg_nodiscard List * list_delete_first_n(List *list, int n)
Definition: list.c:983
#define NIL
Definition: pg_list.h:68
struct ForFiveState ForFiveState
static ForEachState for_each_cell_setup(const List *lst, const ListCell *initcell)
Definition: pg_list.h:447
static Oid list_nth_oid(const List *list, int n)
Definition: pg_list.h:321
#define lfirst_int(lc)
Definition: pg_list.h:173
List * list_difference_ptr(const List *list1, const List *list2)
Definition: list.c:1263
List * list_make2_impl(NodeTag t, ListCell datum1, ListCell datum2)
Definition: list.c:246
List * list_union(const List *list1, const List *list2)
Definition: list.c:1066
pg_nodiscard List * lappend_xid(List *list, TransactionId datum)
Definition: list.c:393
pg_nodiscard List * list_delete_oid(List *list, Oid datum)
Definition: list.c:910
pg_nodiscard List * list_concat_unique_oid(List *list1, const List *list2)
Definition: list.c:1469
struct ForThreeState ForThreeState
pg_nodiscard List * lappend_int(List *list, int datum)
Definition: list.c:357
pg_nodiscard List * list_delete_ptr(List *list, void *datum)
Definition: list.c:872
struct List List
static ListCell * list_head(const List *l)
Definition: pg_list.h:128
List * list_make1_impl(NodeTag t, ListCell datum1)
Definition: list.c:236
pg_nodiscard List * list_concat_unique_int(List *list1, const List *list2)
Definition: list.c:1448
union ListCell ListCell
static ListCell * list_nth_cell(const List *list, int n)
Definition: pg_list.h:277
List * list_difference_oid(const List *list1, const List *list2)
Definition: list.c:1313
pg_nodiscard List * list_append_unique_oid(List *list, Oid datum)
Definition: list.c:1380
pg_nodiscard List * list_concat_copy(const List *list1, const List *list2)
Definition: list.c:598
static ListCell * list_last_cell(const List *list)
Definition: pg_list.h:288
bool list_member_xid(const List *list, TransactionId datum)
Definition: list.c:742
pg_nodiscard List * list_truncate(List *list, int new_size)
Definition: list.c:631
pg_nodiscard List * list_concat_unique(List *list1, const List *list2)
Definition: list.c:1405
pg_nodiscard List * list_delete_int(List *list, int datum)
Definition: list.c:891
pg_nodiscard List * lcons(void *datum, List *list)
Definition: list.c:495
pg_nodiscard List * list_delete_last(List *list)
Definition: list.c:957
List * list_intersection_int(const List *list1, const List *list2)
Definition: list.c:1200
pg_nodiscard List * list_copy_tail(const List *oldlist, int nskip)
Definition: list.c:1613
List * list_difference_int(const List *list1, const List *list2)
Definition: list.c:1288
pg_nodiscard List * list_append_unique_int(List *list, int datum)
Definition: list.c:1368
pg_nodiscard List * list_copy(const List *oldlist)
Definition: list.c:1573
pg_nodiscard List * list_concat_unique_ptr(List *list1, const List *list2)
Definition: list.c:1427
static ListCell * list_tail(const List *l)
Definition: pg_list.h:135
List * list_intersection(const List *list1, const List *list2)
Definition: list.c:1174
pg_nodiscard List * list_insert_nth_oid(List *list, int pos, Oid datum)
Definition: list.c:467
pg_nodiscard List * lcons_oid(Oid datum, List *list)
Definition: list.c:531
int(* list_sort_comparator)(const ListCell *a, const ListCell *b)
Definition: pg_list.h:680
static void * list_nth(const List *list, int n)
Definition: pg_list.h:299
void list_deduplicate_oid(List *list)
Definition: list.c:1495
int list_oid_cmp(const ListCell *p1, const ListCell *p2)
Definition: list.c:1703
static ListCell * lnext(const List *l, const ListCell *c)
Definition: pg_list.h:343
pg_nodiscard List * list_delete_first(List *list)
Definition: list.c:943
static ForEachState for_each_from_setup(const List *lst, int N)
Definition: pg_list.h:423
static ForBothCellState for_both_cell_setup(const List *list1, const ListCell *initcell1, const List *list2, const ListCell *initcell2)
Definition: pg_list.h:549
struct ForBothState ForBothState
List * list_union_oid(const List *list1, const List *list2)
Definition: list.c:1136
struct ForEachState ForEachState
bool list_member_ptr(const List *list, const void *datum)
Definition: list.c:682
void list_free(List *list)
Definition: list.c:1546
bool list_member_int(const List *list, int datum)
Definition: list.c:702
pg_nodiscard List * lappend(List *list, void *datum)
Definition: list.c:339
pg_nodiscard List * list_concat(List *list1, const List *list2)
Definition: list.c:561
pg_nodiscard List * list_insert_nth_int(List *list, int pos, int datum)
Definition: list.c:453
pg_nodiscard List * list_delete_nth_cell(List *list, int n)
Definition: list.c:767
bool list_member_oid(const List *list, Oid datum)
Definition: list.c:722
List * list_make3_impl(NodeTag t, ListCell datum1, ListCell datum2, ListCell datum3)
Definition: list.c:257
List * list_make4_impl(NodeTag t, ListCell datum1, ListCell datum2, ListCell datum3, ListCell datum4)
Definition: list.c:270
#define lfirst_oid(lc)
Definition: pg_list.h:174
int list_int_cmp(const ListCell *p1, const ListCell *p2)
Definition: list.c:1691
static ListCell * list_second_cell(const List *l)
Definition: pg_list.h:142
bool list_member(const List *list, const void *datum)
Definition: list.c:661
struct ForFourState ForFourState
List * list_union_ptr(const List *list1, const List *list2)
Definition: list.c:1090
pg_nodiscard List * list_insert_nth(List *list, int pos, void *datum)
Definition: list.c:439
pg_nodiscard List * list_delete_cell(List *list, ListCell *cell)
Definition: list.c:841
List * list_difference(const List *list1, const List *list2)
Definition: list.c:1237
pg_nodiscard List * list_append_unique(List *list, void *datum)
Definition: list.c:1343
static int list_nth_int(const List *list, int n)
Definition: pg_list.h:310
pg_nodiscard List * lappend_oid(List *list, Oid datum)
Definition: list.c:375
pg_nodiscard List * list_append_unique_ptr(List *list, void *datum)
Definition: list.c:1356
void list_free_deep(List *list)
Definition: list.c:1560
static int list_cell_number(const List *l, const ListCell *c)
Definition: pg_list.h:333
struct ForBothCellState ForBothCellState
List * list_union_int(const List *list1, const List *list2)
Definition: list.c:1113
pg_nodiscard List * list_delete(List *list, void *datum)
Definition: list.c:853
unsigned int Oid
Definition: postgres_ext.h:31
char * c
static int cmp(const chr *x, const chr *y, size_t len)
Definition: regc_locale.c:743
const List * l1
Definition: pg_list.h:88
const List * l2
Definition: pg_list.h:89
const List * l1
Definition: pg_list.h:81
const List * l2
Definition: pg_list.h:82
const List * l
Definition: pg_list.h:75
const List * l5
Definition: pg_list.h:117
const List * l3
Definition: pg_list.h:115
const List * l4
Definition: pg_list.h:116
const List * l2
Definition: pg_list.h:114
const List * l1
Definition: pg_list.h:113
const List * l1
Definition: pg_list.h:104
const List * l4
Definition: pg_list.h:107
const List * l2
Definition: pg_list.h:105
const List * l3
Definition: pg_list.h:106
const List * l2
Definition: pg_list.h:97
const List * l3
Definition: pg_list.h:98
const List * l1
Definition: pg_list.h:96
Definition: pg_list.h:54
int max_length
Definition: pg_list.h:57
int length
Definition: pg_list.h:56
ListCell * elements
Definition: pg_list.h:58
NodeTag type
Definition: pg_list.h:55
ListCell initial_elements[FLEXIBLE_ARRAY_MEMBER]
Definition: pg_list.h:60
int int_value
Definition: pg_list.h:48
Oid oid_value
Definition: pg_list.h:49
void * ptr_value
Definition: pg_list.h:47
TransactionId xid_value
Definition: pg_list.h:50