1 /*
2   Red Black Trees
3   (C) 1999  Andrea Arcangeli <andrea@suse.de>
4   
5   This program is free software; you can redistribute it and/or modify
6   it under the terms of the GNU General Public License as published by
7   the Free Software Foundation; either version 2 of the License, or
8   (at your option) any later version.
9 
10   This program is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13   GNU General Public License for more details.
14 
15   You should have received a copy of the GNU General Public License
16   along with this program; if not, write to the Free Software
17   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18 
19   linux/include/linux/rbtree.h
20 
21   To use rbtrees you'll have to implement your own insert and search cores.
22   This will avoid us to use callbacks and to drop dramatically performances.
23   I know it's not the cleaner way,  but in C (not in C++) to get
24   performances and genericity...
25 
26   See Documentation/rbtree.txt for documentation and samples.
27 */
28 
29 /// D translation of rbtree.h from btrfs-progs (v5.9)
30 module btrfs.c.kernel_lib.rbtree;
31 
32 import core.stdc.config;
33 
34 extern(C):
35 
36 align(c_long.sizeof)
37 struct rb_node {
38 	c_ulong  __rb_parent_color;
39 	rb_node *rb_right;
40 	rb_node *rb_left;
41 }
42     /* The alignment might seem pointless, but allegedly CRIS needs it */
43 
44 struct rb_root {
45 	.rb_node* rb_node;
46 }
47 
48 // D: The rest is not yet translated:
49 /+
50 #define rb_parent(r)   ((struct rb_node *)((r)->__rb_parent_color & ~3))
51 
52 #define RB_ROOT	(struct rb_root) { NULL, }
53 #define	rb_entry(ptr, type, member) container_of(ptr, type, member)
54 
55 #define RB_EMPTY_ROOT(root)  ((root)->rb_node == NULL)
56 
57 /* 'empty' nodes are nodes that are known not to be inserted in an rtbree */
58 #define RB_EMPTY_NODE(node)  \
59 	((node)->__rb_parent_color == (unsigned long)(node))
60 #define RB_CLEAR_NODE(node)  \
61 	((node)->__rb_parent_color = (unsigned long)(node))
62 
63 
64 extern void rb_insert_color(struct rb_node *, struct rb_root *);
65 extern void rb_erase(struct rb_node *, struct rb_root *);
66 
67 
68 /* Find logical next and previous nodes in a tree */
69 extern struct rb_node *rb_next(const struct rb_node *);
70 extern struct rb_node *rb_prev(const struct rb_node *);
71 extern struct rb_node *rb_first(const struct rb_root *);
72 extern struct rb_node *rb_last(const struct rb_root *);
73 
74 /* Postorder iteration - always visit the parent after its children */
75 extern struct rb_node *rb_first_postorder(const struct rb_root *);
76 extern struct rb_node *rb_next_postorder(const struct rb_node *);
77 
78 /* Fast replacement of a single node without remove/rebalance/add/rebalance */
79 extern void rb_replace_node(struct rb_node *victim, struct rb_node *new_node,
80 			    struct rb_root *root);
81 
82 static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
83 				struct rb_node ** rb_link)
84 {
85 	node->__rb_parent_color = (unsigned long)parent;
86 	node->rb_left = node->rb_right = NULL;
87 
88 	*rb_link = node;
89 }
90 
91 #define rb_entry_safe(ptr, type, member) \
92 	({ typeof(ptr) ____ptr = (ptr); \
93 	   ____ptr ? rb_entry(____ptr, type, member) : NULL; \
94 	})
95 
96 /**
97  * rbtree_postorder_for_each_entry_safe - iterate over rb_root in post order of
98  * given type safe against removal of rb_node entry
99  *
100  * @pos:	the 'type *' to use as a loop cursor.
101  * @n:		another 'type *' to use as temporary storage
102  * @root:	'rb_root *' of the rbtree.
103  * @field:	the name of the rb_node field within 'type'.
104  */
105 #define rbtree_postorder_for_each_entry_safe(pos, n, root, field) \
106 	for (pos = rb_entry_safe(rb_first_postorder(root), typeof(*pos), field); \
107 	     pos && ({ n = rb_entry_safe(rb_next_postorder(&pos->field), \
108 			typeof(*pos), field); 1; }); \
109 	     pos = n)
110 +/