| /* |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * Public dictionary API. |
| * @deprecated |
| * AVDictionary is provided for compatibility with libav. It is both in |
| * implementation as well as API inefficient. It does not scale and is |
| * extremely slow with large dictionaries. |
| * It is recommended that new code uses our tree container from tree.c/h |
| * where applicable, which uses AVL trees to achieve O(log n) performance. |
| */ |
| |
| #ifndef AVUTIL_DICT_H |
| #define AVUTIL_DICT_H |
| |
| #include <stdint.h> |
| |
| #include "version.h" |
| |
| /** |
| * @addtogroup lavu_dict AVDictionary |
| * @ingroup lavu_data |
| * |
| * @brief Simple key:value store |
| * |
| * @{ |
| * Dictionaries are used for storing key:value pairs. To create |
| * an AVDictionary, simply pass an address of a NULL pointer to |
| * av_dict_set(). NULL can be used as an empty dictionary wherever |
| * a pointer to an AVDictionary is required. |
| * Use av_dict_get() to retrieve an entry or iterate over all |
| * entries and finally av_dict_free() to free the dictionary |
| * and all its contents. |
| * |
| @code |
| AVDictionary *d = NULL; // "create" an empty dictionary |
| AVDictionaryEntry *t = NULL; |
| |
| av_dict_set(&d, "foo", "bar", 0); // add an entry |
| |
| char *k = av_strdup("key"); // if your strings are already allocated, |
| char *v = av_strdup("value"); // you can avoid copying them like this |
| av_dict_set(&d, k, v, AV_DICT_DONT_STRDUP_KEY | AV_DICT_DONT_STRDUP_VAL); |
| |
| while (t = av_dict_get(d, "", t, AV_DICT_IGNORE_SUFFIX)) { |
| <....> // iterate over all entries in d |
| } |
| av_dict_free(&d); |
| @endcode |
| */ |
| |
| #define AV_DICT_MATCH_CASE 1 /**< Only get an entry with exact-case key match. Only relevant in av_dict_get(). */ |
| #define AV_DICT_IGNORE_SUFFIX 2 /**< Return first entry in a dictionary whose first part corresponds to the search key, |
| ignoring the suffix of the found key string. Only relevant in av_dict_get(). */ |
| #define AV_DICT_DONT_STRDUP_KEY 4 /**< Take ownership of a key that's been |
| allocated with av_malloc() or another memory allocation function. */ |
| #define AV_DICT_DONT_STRDUP_VAL 8 /**< Take ownership of a value that's been |
| allocated with av_malloc() or another memory allocation function. */ |
| #define AV_DICT_DONT_OVERWRITE 16 ///< Don't overwrite existing entries. |
| #define AV_DICT_APPEND 32 /**< If the entry already exists, append to it. Note that no |
| delimiter is added, the strings are simply concatenated. */ |
| #define AV_DICT_MULTIKEY 64 /**< Allow to store several equal keys in the dictionary */ |
| |
| typedef struct AVDictionaryEntry { |
| char *key; |
| char *value; |
| } AVDictionaryEntry; |
| |
| typedef struct AVDictionary AVDictionary; |
| |
| /** |
| * Get a dictionary entry with matching key. |
| * |
| * The returned entry key or value must not be changed, or it will |
| * cause undefined behavior. |
| * |
| * To iterate through all the dictionary entries, you can set the matching key |
| * to the null string "" and set the AV_DICT_IGNORE_SUFFIX flag. |
| * |
| * @param prev Set to the previous matching element to find the next. |
| * If set to NULL the first matching element is returned. |
| * @param key matching key |
| * @param flags a collection of AV_DICT_* flags controlling how the entry is retrieved |
| * @return found entry or NULL in case no matching entry was found in the dictionary |
| */ |
| AVDictionaryEntry *av_dict_get(const AVDictionary *m, const char *key, |
| const AVDictionaryEntry *prev, int flags); |
| |
| /** |
| * Get number of entries in dictionary. |
| * |
| * @param m dictionary |
| * @return number of entries in dictionary |
| */ |
| int av_dict_count(const AVDictionary *m); |
| |
| /** |
| * Set the given entry in *pm, overwriting an existing entry. |
| * |
| * Note: If AV_DICT_DONT_STRDUP_KEY or AV_DICT_DONT_STRDUP_VAL is set, |
| * these arguments will be freed on error. |
| * |
| * Warning: Adding a new entry to a dictionary invalidates all existing entries |
| * previously returned with av_dict_get. |
| * |
| * @param pm pointer to a pointer to a dictionary struct. If *pm is NULL |
| * a dictionary struct is allocated and put in *pm. |
| * @param key entry key to add to *pm (will either be av_strduped or added as a new key depending on flags) |
| * @param value entry value to add to *pm (will be av_strduped or added as a new key depending on flags). |
| * Passing a NULL value will cause an existing entry to be deleted. |
| * @return >= 0 on success otherwise an error code <0 |
| */ |
| int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags); |
| |
| /** |
| * Convenience wrapper for av_dict_set that converts the value to a string |
| * and stores it. |
| * |
| * Note: If AV_DICT_DONT_STRDUP_KEY is set, key will be freed on error. |
| */ |
| int av_dict_set_int(AVDictionary **pm, const char *key, int64_t value, int flags); |
| |
| /** |
| * Parse the key/value pairs list and add the parsed entries to a dictionary. |
| * |
| * In case of failure, all the successfully set entries are stored in |
| * *pm. You may need to manually free the created dictionary. |
| * |
| * @param key_val_sep a 0-terminated list of characters used to separate |
| * key from value |
| * @param pairs_sep a 0-terminated list of characters used to separate |
| * two pairs from each other |
| * @param flags flags to use when adding to dictionary. |
| * AV_DICT_DONT_STRDUP_KEY and AV_DICT_DONT_STRDUP_VAL |
| * are ignored since the key/value tokens will always |
| * be duplicated. |
| * @return 0 on success, negative AVERROR code on failure |
| */ |
| int av_dict_parse_string(AVDictionary **pm, const char *str, |
| const char *key_val_sep, const char *pairs_sep, |
| int flags); |
| |
| /** |
| * Copy entries from one AVDictionary struct into another. |
| * @param dst pointer to a pointer to a AVDictionary struct. If *dst is NULL, |
| * this function will allocate a struct for you and put it in *dst |
| * @param src pointer to source AVDictionary struct |
| * @param flags flags to use when setting entries in *dst |
| * @note metadata is read using the AV_DICT_IGNORE_SUFFIX flag |
| * @return 0 on success, negative AVERROR code on failure. If dst was allocated |
| * by this function, callers should free the associated memory. |
| */ |
| int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags); |
| |
| /** |
| * Free all the memory allocated for an AVDictionary struct |
| * and all keys and values. |
| */ |
| void av_dict_free(AVDictionary **m); |
| |
| /** |
| * Get dictionary entries as a string. |
| * |
| * Create a string containing dictionary's entries. |
| * Such string may be passed back to av_dict_parse_string(). |
| * @note String is escaped with backslashes ('\'). |
| * |
| * @param[in] m dictionary |
| * @param[out] buffer Pointer to buffer that will be allocated with string containg entries. |
| * Buffer must be freed by the caller when is no longer needed. |
| * @param[in] key_val_sep character used to separate key from value |
| * @param[in] pairs_sep character used to separate two pairs from each other |
| * @return >= 0 on success, negative on error |
| * @warning Separators cannot be neither '\\' nor '\0'. They also cannot be the same. |
| */ |
| int av_dict_get_string(const AVDictionary *m, char **buffer, |
| const char key_val_sep, const char pairs_sep); |
| |
| /** |
| * @} |
| */ |
| |
| #endif /* AVUTIL_DICT_H */ |
