/*
- *
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
*/
/**
- * @file Public dictionary API.
+ * @file
+ * Public dictionary API.
*/
#ifndef AVUTIL_DICT_H
#define AVUTIL_DICT_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
#define AV_DICT_IGNORE_SUFFIX 2
-#define AV_DICT_DONT_STRDUP_KEY 4
-#define AV_DICT_DONT_STRDUP_VAL 8
+#define AV_DICT_DONT_STRDUP_KEY 4 /**< Take ownership of a key that's been
+ allocated with av_malloc() and children. */
+#define AV_DICT_DONT_STRDUP_VAL 8 /**< Take ownership of a value that's been
+ allocated with av_malloc() and children. */
#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. */
-typedef struct {
+typedef struct AVDictionaryEntry {
char *key;
char *value;
} AVDictionaryEntry;
* @param flags Allows case as well as suffix-insensitive comparisons.
* @return Found entry or NULL, changing key or value leads to undefined behavior.
*/
-AVDictionaryEntry *
-av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags);
+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.
* a dictionary struct is allocated and put in *pm.
* @param key entry key to add to *pm (will be av_strduped depending on flags)
* @param value entry value to add to *pm (will be av_strduped depending on flags).
- * Passing a NULL value will cause an existing tag to be deleted.
+ * 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);
+/**
+ * Parse the key/value pairs list and add to a 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,
* @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.
*/
-void av_dict_copy(AVDictionary **dst, AVDictionary *src, int flags);
+int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags);
/**
- * Free all the memory allocated for an AVDictionary struct.
+ * Free all the memory allocated for an AVDictionary struct
+ * and all keys and values.
*/
void av_dict_free(AVDictionary **m);
-#endif // AVUTIL_DICT_H
+/**
+ * @}
+ */
+
+#endif /* AVUTIL_DICT_H */