tools/perf/util/rblist.c

   1 /*
   2  * Based on strlist.c by:
   3  * (c) 2009 Arnaldo Carvalho de Melo <acme@redhat.com>
   4  *
   5  * Licensed under the GPLv2.
   6  */
   7
   8 #include <errno.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11
  12 #include "rblist.h"
  13
  14 int rblist__add_node(struct rblist *rblist, const void *new_entry)
  15 {
  16         struct rb_node **p = &rblist->entries.rb_root.rb_node;
  17         struct rb_node *parent = NULL, *new_node;
  18         bool leftmost = true;
  19
  20         while (*p != NULL) {
  21                 int rc;
  22
  23                 parent = *p;
  24
  25                 rc = rblist->node_cmp(parent, new_entry);
  26                 if (rc > 0)
  27                         p = &(*p)->rb_left;
  28                 else if (rc < 0) {
  29                         p = &(*p)->rb_right;
  30                         leftmost = false;
  31                 }
  32                 else
  33                         return -EEXIST;
  34         }
  35
  36         new_node = rblist->node_new(rblist, new_entry);
  37         if (new_node == NULL)
  38                 return -ENOMEM;
  39
  40         rb_link_node(new_node, parent, p);
  41         rb_insert_color_cached(new_node, &rblist->entries, leftmost);
  42         ++rblist->nr_entries;
  43
  44         return 0;
  45 }
  46
  47 void rblist__remove_node(struct rblist *rblist, struct rb_node *rb_node)
  48 {
  49         rb_erase_cached(rb_node, &rblist->entries);
  50         --rblist->nr_entries;
  51         rblist->node_delete(rblist, rb_node);
  52 }
  53
  54 static struct rb_node *__rblist__findnew(struct rblist *rblist,
  55                                          const void *entry,
  56                                          bool create)
  57 {
  58         struct rb_node **p = &rblist->entries.rb_root.rb_node;
  59         struct rb_node *parent = NULL, *new_node = NULL;
  60         bool leftmost = true;
  61
  62         while (*p != NULL) {
  63                 int rc;
  64
  65                 parent = *p;
  66
  67                 rc = rblist->node_cmp(parent, entry);
  68                 if (rc > 0)
  69                         p = &(*p)->rb_left;
  70                 else if (rc < 0) {
  71                         p = &(*p)->rb_right;
  72                         leftmost = false;
  73                 }
  74                 else
  75                         return parent;
  76         }
  77
  78         if (create) {
  79                 new_node = rblist->node_new(rblist, entry);
  80                 if (new_node) {
  81                         rb_link_node(new_node, parent, p);
  82                         rb_insert_color_cached(new_node,
  83                                                &rblist->entries, leftmost);
  84                         ++rblist->nr_entries;
  85                 }
  86         }
  87
  88         return new_node;
  89 }
  90
  91 struct rb_node *rblist__find(struct rblist *rblist, const void *entry)
  92 {
  93         return __rblist__findnew(rblist, entry, false);
  94 }
  95
  96 struct rb_node *rblist__findnew(struct rblist *rblist, const void *entry)
  97 {
  98         return __rblist__findnew(rblist, entry, true);
  99 }
 100
 101 void rblist__init(struct rblist *rblist)
 102 {
 103         if (rblist != NULL) {
 104                 rblist->entries  = RB_ROOT_CACHED;
 105                 rblist->nr_entries = 0;
 106         }
 107
 108         return;
 109 }
 110
 111 void rblist__exit(struct rblist *rblist)
 112 {
 113         struct rb_node *pos, *next = rb_first_cached(&rblist->entries);
 114
 115         while (next) {
 116                 pos = next;
 117                 next = rb_next(pos);
 118                 rblist__remove_node(rblist, pos);
 119         }
 120 }
 121
 122 void rblist__delete(struct rblist *rblist)
 123 {
 124         if (rblist != NULL) {
 125                 rblist__exit(rblist);
 126                 free(rblist);
 127         }
 128 }
 129
 130 struct rb_node *rblist__entry(const struct rblist *rblist, unsigned int idx)
 131 {
 132         struct rb_node *node;
 133
 134         for (node = rb_first_cached(&rblist->entries); node;
 135              node = rb_next(node)) {
 136                 if (!idx--)
 137                         return node;
 138         }
 139
 140         return NULL;
 141 }