utils/dict.h

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/* Simple Plugin API
 *
 * Copyright © 2018 Wim Taymans
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */
 
#ifndef SPA_DICT_H
#define SPA_DICT_H
 
#ifdef __cplusplus
extern "C" {
#endif
 
#include <string.h>
 
#include <spa/utils/defs.h>
 
struct spa_dict_item {
        const char *key;
        const char *value;
};
 
#define SPA_DICT_ITEM_INIT(key,value) (struct spa_dict_item) { key, value }
 
struct spa_dict {
#define SPA_DICT_FLAG_SORTED    (1<<0)          
        uint32_t flags;
        uint32_t n_items;
        const struct spa_dict_item *items;
};
 
#define SPA_DICT_INIT(items,n_items) (struct spa_dict) { 0, n_items, items }
#define SPA_DICT_INIT_ARRAY(items) (struct spa_dict) { 0, SPA_N_ELEMENTS(items), items }
 
#define spa_dict_for_each(item, dict)                           \
        for ((item) = (dict)->items;                            \
             (item) < &(dict)->items[(dict)->n_items];          \
             (item)++)
 
/* static */ inline int spa_dict_item_compare(const void *i1, const void *i2)
{
        const struct spa_dict_item *it1 = (const struct spa_dict_item *)i1,
              *it2 = (const struct spa_dict_item *)i2;
        return strcmp(it1->key, it2->key);
}
 
/* static */ inline void spa_dict_qsort(struct spa_dict *dict)
{
        qsort((void*)dict->items, dict->n_items, sizeof(struct spa_dict_item),
                        spa_dict_item_compare);
        SPA_FLAG_SET(dict->flags, SPA_DICT_FLAG_SORTED);
}
 
/* static */ inline const struct spa_dict_item *spa_dict_lookup_item(const struct spa_dict *dict,
                                                               const char *key)
{
        const struct spa_dict_item *item;
 
        if (SPA_FLAG_IS_SET(dict->flags, SPA_DICT_FLAG_SORTED)) {
                struct spa_dict_item k = SPA_DICT_ITEM_INIT(key, NULL);
                item = (const struct spa_dict_item *)bsearch(&k,
                                (const void *) dict->items, dict->n_items,
                                sizeof(struct spa_dict_item),
                                spa_dict_item_compare);
                if (item != NULL)
                        return item;
        } else {
                spa_dict_for_each(item, dict) {
                        if (!strcmp(item->key, key))
                                return item;
                }
        }
        return NULL;
}
 
/* static */ inline const char *spa_dict_lookup(const struct spa_dict *dict, const char *key)
{
        const struct spa_dict_item *item = spa_dict_lookup_item(dict, key);
        return item ? item->value : NULL;
}
 
#ifdef __cplusplus
}  /* extern "C" */
#endif
 
#endif /* SPA_DICT_H */