#include <string.h>

#include <import/eb32tree.h>

#include <import/ebistree.h>

#include <haproxy/dict.h>

#include <haproxy/thread.h>

struct dict *new_dict(const char *name)

{

  struct dict *dict;

  dict = malloc(sizeof *dict);

  if (!dict)

    return NULL;

  dict->name     = name;

  dict->values   = EB_ROOT_UNIQUE;

  HA_RWLOCK_INIT(&dict->rwlock);

  return dict;

}

/*

 * Allocate a new dictionary entry with <s> as string value which is strdup()'ed.

 * Returns the new allocated entry if succeeded, NULL if not.

 */

static struct dict_entry *new_dict_entry(char *s)

{

  struct dict_entry *de;

  de = calloc(1, sizeof *de);

  if (!de)

    return NULL;

  de->value.key = strdup(s);

  if (!de->value.key)

    goto err;

  de->len = strlen(s);

  de->refcount = 1;

  return de;

 err:

  ha_free(&de->value.key);

  de->len = 0;

  free(de);

  return NULL;

}

/*

 * Release the memory allocated for <de> dictionary entry.

 */

static void free_dict_entry(struct dict_entry *de)

{

  de->refcount = 0;

  ha_free(&de->value.key);

  free(de);

}

/*

 * Simple function to lookup dictionary entries with <s> as value.

 */

static struct dict_entry *__dict_lookup(struct dict *d, const char *s)

{

  struct dict_entry *de;

  struct ebpt_node *node;

  de = NULL;

  node = ebis_lookup(&d->values, s);

  if (node)

    de = container_of(node, struct dict_entry, value);

  return de;

}

/*

 * Insert an entry in <d> dictionary with <s> as value. *

 */

struct dict_entry *dict_insert(struct dict *d, char *s)

{

  struct dict_entry *de;

  struct ebpt_node *n;

  HA_RWLOCK_RDLOCK(DICT_LOCK, &d->rwlock);

  de = __dict_lookup(d, s);

  HA_RWLOCK_RDUNLOCK(DICT_LOCK, &d->rwlock);

  if (de) {

    HA_ATOMIC_INC(&de->refcount);

    return de;

  }

  de = new_dict_entry(s);

  if (!de)

    return NULL;

  HA_RWLOCK_WRLOCK(DICT_LOCK, &d->rwlock);

  n = ebis_insert(&d->values, &de->value);

  HA_RWLOCK_WRUNLOCK(DICT_LOCK, &d->rwlock);

  if (n != &de->value) {

    free_dict_entry(de);

    de = container_of(n, struct dict_entry, value);

  }

  return de;

}

/*

 * Unreference a dict entry previously acquired with <dict_insert>.

 * If this is the last live reference to the entry, it is

 * removed from the dictionary.

 */

void dict_entry_unref(struct dict *d, struct dict_entry *de)

{

  if (!de)

    return;

  if (HA_ATOMIC_SUB_FETCH(&de->refcount, 1) != 0)

    return;

  HA_RWLOCK_WRLOCK(DICT_LOCK, &d->rwlock);

  ebpt_delete(&de->value);

  HA_RWLOCK_WRUNLOCK(DICT_LOCK, &d->rwlock);

  free_dict_entry(de);

}