cosmetics: Write NULL pointer equality checks more compactly

[ffmpeg] / libavutil / dict.h

diff --git a/libavutil/dict.h b/libavutil/dict.h
index 6e28b61406f782677f385af22a91fb6dd6ec7f83..e4aee27ca3b1f32472fe74b52a9d65f7fdfc9d49 100644 (file)
--- a/libavutil/dict.h
+++ b/libavutil/dict.h
@@ -40,21 +40,21 @@
  * entries and finally av_dict_free() to free the dictionary
  * and all its contents.
  *
- * @code
- * AVDictionary *d = NULL;                // "create" an empty dictionary
- * 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);
- *
- * AVDictionaryEntry *t = NULL;
- * while (t = av_dict_get(d, "", t, AV_DICT_IGNORE_SUFFIX)) {
- *     <....>                             // iterate over all entries in d
- * }
- *
- * av_dict_free(&d);
- * @endcode
+ @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
  *
  */
 
@@ -68,7 +68,7 @@
 #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;
@@ -83,8 +83,16 @@ typedef struct AVDictionary AVDictionary;
  * @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.
@@ -93,11 +101,28 @@ av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int
  * 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,
@@ -106,7 +131,7 @@ int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags
  * @param flags flags to use when setting entries in *dst
  * @note metadata is read using the AV_DICT_IGNORE_SUFFIX flag
  */
-void av_dict_copy(AVDictionary **dst, AVDictionary *src, int flags);
+void av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags);
 
 /**
  * Free all the memory allocated for an AVDictionary struct
@@ -118,4 +143,4 @@ void av_dict_free(AVDictionary **m);
  * @}
  */
 
-#endif // AVUTIL_DICT_H
+#endif /* AVUTIL_DICT_H */