3 * This file is part of FFmpeg.
5 * FFmpeg is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2.1 of the License, or (at your option) any later version.
10 * FFmpeg is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with FFmpeg; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 * @file Public dictionary API.
27 #define AV_DICT_MATCH_CASE 1
28 #define AV_DICT_IGNORE_SUFFIX 2
29 #define AV_DICT_DONT_STRDUP_KEY 4
30 #define AV_DICT_DONT_STRDUP_VAL 8
31 #define AV_DICT_DONT_OVERWRITE 16 ///< Don't overwrite existing entries.
32 #define AV_DICT_APPEND 32 /**< If the entry already exists, append to it. Note that no
33 delimiter is added, the strings are simply concatenated. */
40 typedef struct AVDictionary AVDictionary;
43 * Get a dictionary entry with matching key.
45 * @param prev Set to the previous matching element to find the next.
46 * If set to NULL the first matching element is returned.
47 * @param flags Allows case as well as suffix-insensitive comparisons.
48 * @return Found entry or NULL, changing key or value leads to undefined behavior.
51 av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags);
54 * Set the given entry in *pm, overwriting an existing entry.
56 * @param pm pointer to a pointer to a dictionary struct. If *pm is NULL
57 * a dictionary struct is allocated and put in *pm.
58 * @param key entry key to add to *pm (will be av_strduped depending on flags)
59 * @param value entry value to add to *pm (will be av_strduped depending on flags).
60 * Passing a NULL value will cause an existing tag to be deleted.
61 * @return >= 0 on success otherwise an error code <0
63 int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags);
66 * Copy entries from one AVDictionary struct into another.
67 * @param dst pointer to a pointer to a AVDictionary struct. If *dst is NULL,
68 * this function will allocate a struct for you and put it in *dst
69 * @param src pointer to source AVDictionary struct
70 * @param flags flags to use when setting entries in *dst
71 * @note metadata is read using the AV_DICT_IGNORE_SUFFIX flag
73 void av_dict_copy(AVDictionary **dst, AVDictionary *src, int flags);
76 * Free all the memory allocated for an AVDictionary struct.
78 void av_dict_free(AVDictionary **m);
80 #endif // AVUTIL_DICT_H