kernel/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_node;
  17         struct rb_node *parent = NULL, *new_node;
  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                 else
  30                         return -EEXIST;
  31         }
  32
  33         new_node = rblist->node_new(rblist, new_entry);
  34         if (new_node == NULL)
  35                 return -ENOMEM;
  36
  37         rb_link_node(new_node, parent, p);
  38         rb_insert_color(new_node, &rblist->entries);
  39         ++rblist->nr_entries;
  40
  41         return 0;
  42 }
  43
  44 void rblist__remove_node(struct rblist *rblist, struct rb_node *rb_node)
  45 {
  46         rb_erase(rb_node, &rblist->entries);
  47         --rblist->nr_entries;
  48         rblist->node_delete(rblist, rb_node);
  49 }
  50
  51 static struct rb_node *__rblist__findnew(struct rblist *rblist,
  52                                          const void *entry,
  53                                          bool create)
  54 {
  55         struct rb_node **p = &rblist->entries.rb_node;
  56         struct rb_node *parent = NULL, *new_node = NULL;
  57
  58         while (*p != NULL) {
  59                 int rc;
  60
  61                 parent = *p;
  62
  63                 rc = rblist->node_cmp(parent, entry);
  64                 if (rc > 0)
  65                         p = &(*p)->rb_left;
  66                 else if (rc < 0)
  67                         p = &(*p)->rb_right;
  68                 else
  69                         return parent;
  70         }
  71
  72         if (create) {
  73                 new_node = rblist->node_new(rblist, entry);
  74                 if (new_node) {
  75                         rb_link_node(new_node, parent, p);
  76                         rb_insert_color(new_node, &rblist->entries);
  77                         ++rblist->nr_entries;
  78                 }
  79         }
  80
  81         return new_node;
  82 }
  83
  84 struct rb_node *rblist__find(struct rblist *rblist, const void *entry)
  85 {
  86         return __rblist__findnew(rblist, entry, false);
  87 }
  88
  89 struct rb_node *rblist__findnew(struct rblist *rblist, const void *entry)
  90 {
  91         return __rblist__findnew(rblist, entry, true);
  92 }
  93
  94 void rblist__init(struct rblist *rblist)
  95 {
  96         if (rblist != NULL) {
  97                 rblist->entries  = RB_ROOT;
  98                 rblist->nr_entries = 0;
  99         }
 100
 101         return;
 102 }
 103
 104 void rblist__delete(struct rblist *rblist)
 105 {
 106         if (rblist != NULL) {
 107                 struct rb_node *pos, *next = rb_first(&rblist->entries);
 108
 109                 while (next) {
 110                         pos = next;
 111                         next = rb_next(pos);
 112                         rblist__remove_node(rblist, pos);
 113                 }
 114                 free(rblist);
 115         }
 116 }
 117
 118 struct rb_node *rblist__entry(const struct rblist *rblist, unsigned int idx)
 119 {
 120         struct rb_node *node;
 121
 122         for (node = rb_first(&rblist->entries); node; node = rb_next(node)) {
 123                 if (!idx--)
 124                         return node;
 125         }
 126
 127         return NULL;
 128 }