[FFmpeg-devel] [PATCH v2 5/5] avutil/dict: Improve documentation
Marvin Scholz
epirat07 at gmail.com
Sat Sep 24 17:36:59 EEST 2022
Mostly consistent formatting and consistently ordering of
warnings/notes to be next to the description.
Additionally group the AV_DICT_* macros.
---
libavutil/dict.h | 91 +++++++++++++++++++++++++++++-------------------
1 file changed, 55 insertions(+), 36 deletions(-)
diff --git a/libavutil/dict.h b/libavutil/dict.h
index 344afb452b..e4bc330a44 100644
--- a/libavutil/dict.h
+++ b/libavutil/dict.h
@@ -41,13 +41,15 @@
* @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 and av_dict_iterate() to
- * iterate over all entries and finally av_dict_free() to free the
- * dictionary and all its contents.
+ * 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.
+ * - To **insert an entry**, use av_dict_set().
+ * - Use av_dict_get() to **retrieve an entry**.
+ * - To **iterate over all entries**, use av_dict_iterate().
+ * - In order to **free the dictionary and all its contents**, use av_dict_free().
*
@code
AVDictionary *d = NULL; // "create" an empty dictionary
@@ -59,13 +61,18 @@
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_iterate(d, t)) {
+ while ((t = av_dict_iterate(d, t))) {
<....> // iterate over all entries in d
}
av_dict_free(&d);
@endcode
*/
+/**
+ * @name AVDictionary Flags
+ * Flags that influence behavior of the matching of keys or insertion to the dictionary.
+ * @{
+ */
#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(). */
@@ -73,10 +80,13 @@
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_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. */
+ 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;
@@ -91,11 +101,13 @@ typedef struct AVDictionary AVDictionary;
* The returned entry key or value must not be changed, or it will
* cause undefined behavior.
*
- * @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
+ * @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);
@@ -144,20 +156,21 @@ int av_dict_count(const AVDictionary *m);
* @warning Adding a new entry to a dictionary invalidates all existing entries
* previously returned with av_dict_get() or av_dict_iterate().
*
- * @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
+ * @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
+ * 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.
+ * 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);
@@ -167,14 +180,15 @@ int av_dict_set_int(AVDictionary **pm, const char *key, int64_t value, int flags
* 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
+ * @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
+ * @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
+ * @param flags Flags to use when adding to the 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,
@@ -183,11 +197,14 @@ int av_dict_parse_string(AVDictionary **pm, const char *str,
/**
* 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
+ *
+ * @note Metadata is read using the ::AV_DICT_IGNORE_SUFFIX flag
+ *
+ * @param dst Pointer to a pointer to a AVDictionary struct to copy into. If *dst is NULL,
+ * this function will allocate a struct for you and put it in *dst
+ * @param src Pointer to the source AVDictionary struct to copy items from.
+ * @param flags Flags to use when setting entries in *dst
+ *
* @return 0 on success, negative AVERROR code on failure. If dst was allocated
* by this function, callers should free the associated memory.
*/
@@ -206,13 +223,15 @@ void av_dict_free(AVDictionary **m);
* Such string may be passed back to av_dict_parse_string().
* @note String is escaped with backslashes ('\').
*
- * @param[in] m dictionary
+ * @warning Separators cannot be neither '\\' nor '\0'. They also cannot be the same.
+ *
+ * @param[in] m The 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
+ * @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);
--
2.37.0 (Apple Git-136)
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