blob: aba5578899b034dd439d11e012f232960fb9cba5 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
/*-------------------------------------------------------------------------
*
* proclist_types.h
* doubly-linked lists of pgprocnos
*
* See proclist.h for functions that operate on these types.
*
* Portions Copyright (c) 2016-2020, PostgreSQL Global Development Group
*
* IDENTIFICATION
* src/include/storage/proclist_types.h
*-------------------------------------------------------------------------
*/
#ifndef PROCLIST_TYPES_H
#define PROCLIST_TYPES_H
/*
* A node in a doubly-linked list of processes. The link fields contain
* the 0-based PGPROC indexes of the next and previous process, or
* INVALID_PGPROCNO in the next-link of the last node and the prev-link
* of the first node. A node that is currently not in any list
* should have next == prev == 0; this is not a possible state for a node
* that is in a list, because we disallow circularity.
*/
typedef struct proclist_node
{
int next; /* pgprocno of the next PGPROC */
int prev; /* pgprocno of the prev PGPROC */
} proclist_node;
/*
* Header of a doubly-linked list of PGPROCs, identified by pgprocno.
* An empty list is represented by head == tail == INVALID_PGPROCNO.
*/
typedef struct proclist_head
{
int head; /* pgprocno of the head PGPROC */
int tail; /* pgprocno of the tail PGPROC */
} proclist_head;
/*
* List iterator allowing some modifications while iterating.
*/
typedef struct proclist_mutable_iter
{
int cur; /* pgprocno of the current PGPROC */
int next; /* pgprocno of the next PGPROC */
} proclist_mutable_iter;
#endif /* PROCLIST_TYPES_H */
|
