Rename ffmpeg-4.2-fit to ffmpeg-4-fit

trunk/3rdparty/ffmpeg-4-fit/libavutil/dict.h

@@ -0,0 +1,200 @@
+/*
+ * 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 */