rblist.c

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/*
 * Based on strlist.c by:
 * (c) 2009 Arnaldo Carvalho de Melo <[email protected]>
 *
 * Licensed under the GPLv2.
 */

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>

#include "rblist.h"

int rblist__add_node(struct rblist *rblist, const void *new_entry)
{
    struct rb_node **p = &rblist->entries.rb_node;
    struct rb_node *parent = NULL, *new_node;

    while (*p != NULL) {
        int rc;

        parent = *p;

        rc = rblist->node_cmp(parent, new_entry);
        if (rc > 0)
            p = &(*p)->rb_left;
        else if (rc < 0)
            p = &(*p)->rb_right;
        else
            return -EEXIST;
    }

    new_node = rblist->node_new(rblist, new_entry);
    if (new_node == NULL)
        return -ENOMEM;

    rb_link_node(new_node, parent, p);
    rb_insert_color(new_node, &rblist->entries);
    ++rblist->nr_entries;

    return 0;
}

void rblist__remove_node(struct rblist *rblist, struct rb_node *rb_node)
{
    rb_erase(rb_node, &rblist->entries);
    rblist->node_delete(rblist, rb_node);
}

struct rb_node *rblist__find(struct rblist *rblist, const void *entry)
{
    struct rb_node **p = &rblist->entries.rb_node;
    struct rb_node *parent = NULL;

    while (*p != NULL) {
        int rc;

        parent = *p;

        rc = rblist->node_cmp(parent, entry);
        if (rc > 0)
            p = &(*p)->rb_left;
        else if (rc < 0)
            p = &(*p)->rb_right;
        else
            return parent;
    }

    return NULL;
}

void rblist__init(struct rblist *rblist)
{
    if (rblist != NULL) {
        rblist->entries  = RB_ROOT;
        rblist->nr_entries = 0;
    }

    return;
}

void rblist__delete(struct rblist *rblist)
{
    if (rblist != NULL) {
        struct rb_node *pos, *next = rb_first(&rblist->entries);

        while (next) {
            pos = next;
            next = rb_next(pos);
            rb_erase(pos, &rblist->entries);
            rblist->node_delete(rblist, pos);
        }
        free(rblist);
    }
}

struct rb_node *rblist__entry(const struct rblist *rblist, unsigned int idx)
{
    struct rb_node *node;

    for (node = rb_first(&rblist->entries); node; node = rb_next(node)) {
        if (!idx--)
            return node;
    }

    return NULL;
}