tools/perf/util/rblist.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Based on strlist.c by:
   4  * (c) 2009 Arnaldo Carvalho de Melo <acme@redhat.com>
   5  */
   6
   7 #include <errno.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10
  11 #include "rblist.h"
  12
  13 int rblist__add_node(struct rblist *rblist, const void *new_entry)
  14 {
  15         struct rb_node **p = &rblist->entries.rb_root.rb_node;
  16         struct rb_node *parent = NULL, *new_node;
  17         bool leftmost = true;
  18
  19         while (*p != NULL) {
  20                 int rc;
  21
  22                 parent = *p;
  23
  24                 rc = rblist->node_cmp(parent, new_entry);
  25                 if (rc > 0)
  26                         p = &(*p)->rb_left;
  27                 else if (rc < 0) {
  28                         p = &(*p)->rb_right;
  29                         leftmost = false;
  30                 }
  31                 else
  32                         return -EEXIST;
  33         }
  34
  35         new_node = rblist->node_new(rblist, new_entry);
  36         if (new_node == NULL)
  37                 return -ENOMEM;
  38
  39         rb_link_node(new_node, parent, p);
  40         rb_insert_color_cached(new_node, &rblist->entries, leftmost);
  41         ++rblist->nr_entries;
  42
  43         return 0;
  44 }
  45
  46 void rblist__remove_node(struct rblist *rblist, struct rb_node *rb_node)
  47 {
  48         rb_erase_cached(rb_node, &rblist->entries);
  49         --rblist->nr_entries;
  50         rblist->node_delete(rblist, rb_node);
  51 }
  52
  53 static struct rb_node *__rblist__findnew(struct rblist *rblist,
  54                                          const void *entry,
  55                                          bool create)
  56 {
  57         struct rb_node **p = &rblist->entries.rb_root.rb_node;
  58         struct rb_node *parent = NULL, *new_node = NULL;
  59         bool leftmost = true;
  60
  61         while (*p != NULL) {
  62                 int rc;
  63
  64                 parent = *p;
  65
  66                 rc = rblist->node_cmp(parent, entry);
  67                 if (rc > 0)
  68                         p = &(*p)->rb_left;
  69                 else if (rc < 0) {
  70                         p = &(*p)->rb_right;
  71                         leftmost = false;
  72                 }
  73                 else
  74                         return parent;
  75         }
  76
  77         if (create) {
  78                 new_node = rblist->node_new(rblist, entry);
  79                 if (new_node) {
  80                         rb_link_node(new_node, parent, p);
  81                         rb_insert_color_cached(new_node,
  82                                                &rblist->entries, leftmost);
  83                         ++rblist->nr_entries;
  84                 }
  85         }
  86
  87         return new_node;
  88 }
  89
  90 struct rb_node *rblist__find(struct rblist *rblist, const void *entry)
  91 {
  92         return __rblist__findnew(rblist, entry, false);
  93 }
  94
  95 struct rb_node *rblist__findnew(struct rblist *rblist, const void *entry)
  96 {
  97         return __rblist__findnew(rblist, entry, true);
  98 }
  99
 100 void rblist__init(struct rblist *rblist)
 101 {
 102         if (rblist != NULL) {
 103                 rblist->entries  = RB_ROOT_CACHED;
 104                 rblist->nr_entries = 0;
 105         }
 106
 107         return;
 108 }
 109
 110 void rblist__exit(struct rblist *rblist)
 111 {
 112         struct rb_node *pos, *next = rb_first_cached(&rblist->entries);
 113
 114         while (next) {
 115                 pos = next;
 116                 next = rb_next(pos);
 117                 rblist__remove_node(rblist, pos);
 118         }
 119 }
 120
 121 void rblist__delete(struct rblist *rblist)
 122 {
 123         if (rblist != NULL) {
 124                 rblist__exit(rblist);
 125                 free(rblist);
 126         }
 127 }
 128
 129 struct rb_node *rblist__entry(const struct rblist *rblist, unsigned int idx)
 130 {
 131         struct rb_node *node;
 132
 133         for (node = rb_first_cached(&rblist->entries); node;
 134              node = rb_next(node)) {
 135                 if (!idx--)
 136                         return node;
 137         }
 138
 139         return NULL;
 140 }