Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit51384cc

Browse files
committed
Add detached node functions to ilist
These allow to test whether an element is in a list by checking whetherprev/next are NULL. Needed to replace SHMQueueIsDetached() when convertingfrom SHM_QUEUE to ilist.h style lists.Reviewed-by: Thomas Munro <thomas.munro@gmail.com>Discussion:https://postgr.es/m/20221120055930.t6kl3tyivzhlrzu2@awork3.anarazel.deDiscussion:https://postgr.es/m/20200211042229.msv23badgqljrdg2@alap3.anarazel.de
1 parent2b16208 commit51384cc

File tree

1 file changed

+63
-0
lines changed

1 file changed

+63
-0
lines changed

‎src/include/lib/ilist.h

Lines changed: 63 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -316,6 +316,17 @@ dlist_init(dlist_head *head)
316316
head->head.next=head->head.prev=&head->head;
317317
}
318318

319+
/*
320+
* Initialize a doubly linked list element.
321+
*
322+
* This is only needed when dlist_node_is_detached() may be needed.
323+
*/
324+
staticinlinevoid
325+
dlist_node_init(dlist_node*node)
326+
{
327+
node->next=node->prev=NULL;
328+
}
329+
319330
/*
320331
* Is the list empty?
321332
*
@@ -397,6 +408,19 @@ dlist_delete(dlist_node *node)
397408
node->next->prev=node->prev;
398409
}
399410

411+
/*
412+
* Like dlist_delete(), but also sets next/prev to NULL to signal not being in
413+
* a list.
414+
*/
415+
staticinlinevoid
416+
dlist_delete_thoroughly(dlist_node*node)
417+
{
418+
node->prev->next=node->next;
419+
node->next->prev=node->prev;
420+
node->next=NULL;
421+
node->prev=NULL;
422+
}
423+
400424
/*
401425
* Same as dlist_delete, but performs checks in ILIST_DEBUG builds to ensure
402426
* that 'node' belongs to 'head'.
@@ -408,6 +432,17 @@ dlist_delete_from(dlist_head *head, dlist_node *node)
408432
dlist_delete(node);
409433
}
410434

435+
/*
436+
* Like dlist_delete_from, but also sets next/prev to NULL to signal not
437+
* being in a list.
438+
*/
439+
staticinlinevoid
440+
dlist_delete_from_thoroughly(dlist_head*head,dlist_node*node)
441+
{
442+
dlist_member_check(head,node);
443+
dlist_delete_thoroughly(node);
444+
}
445+
411446
/*
412447
* Remove and return the first node from a list (there must be one).
413448
*/
@@ -480,6 +515,21 @@ dlist_has_prev(const dlist_head *head, const dlist_node *node)
480515
returnnode->prev!=&head->head;
481516
}
482517

518+
/*
519+
* Check if node is detached. A node is only detached if it either has been
520+
* initialized with dlist_init_node(), or deleted with
521+
* dlist_delete_thoroughly() / dlist_delete_from_thoroughly() /
522+
* dclist_delete_from_thoroughly().
523+
*/
524+
staticinlinebool
525+
dlist_node_is_detached(constdlist_node*node)
526+
{
527+
Assert((node->next==NULL&&node->prev==NULL)||
528+
(node->next!=NULL&&node->prev!=NULL));
529+
530+
returnnode->next==NULL;
531+
}
532+
483533
/*
484534
* Return the next node in the list (there must be one).
485535
*/
@@ -718,6 +768,19 @@ dclist_delete_from(dclist_head *head, dlist_node *node)
718768
head->count--;
719769
}
720770

771+
/*
772+
* Like dclist_delete_from(), but also sets next/prev to NULL to signal not
773+
* being in a list.
774+
*/
775+
staticinlinevoid
776+
dclist_delete_from_thoroughly(dclist_head*head,dlist_node*node)
777+
{
778+
Assert(head->count>0);
779+
780+
dlist_delete_from_thoroughly(&head->dlist,node);
781+
head->count--;
782+
}
783+
721784
/*
722785
* dclist_pop_head_node
723786
*Remove and return the first node from a list (there must be one).

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp