201 lines
8.1 KiB
C
201 lines
8.1 KiB
C
|
/*
|
||
|
* 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 */
|