FFmpeg/libavutil/dict.h
Michael Niedermayer 58257ea29e Merge remote-tracking branch 'qatar/master'
* qatar/master: (28 commits)
  mp3enc: write a xing frame containing number of frames in the file
  lavf: update AVStream.nb_frames when muxing.
  ffmpeg: remove unused variables from InputStream.
  doc: update ffmpeg -ar and -ac documentation to reflect reality.
  ffmpeg: remove pointless if (nb_input_files)
  ffmpeg: merge input_files_ts_offset into input_files.
  ffmpeg: merge input_codecs into input_streams.
  ffmpeg: drop AV prefixes from struct names.
  ffmpeg: deprecate loop_input and loop_output options
  gif: add loop private option.
  img2: add loop private option.
  AVOptions: in av_opt_find() don't return named constants unless unit is specified.
  x11grab: replace undocumented nomouse hackery with a private option.
  dict: extend documentation.
  lls: whitespace cosmetics
  docs: Use proper markup for a literal command line option
  docs: Remove a remark that isn't relevant any longer
  docs: Explain how to regenerate import libraries with MSVC tools
  docs: Mention that libraries for MSVC can be built with a cross compiler
  docs: Remove old docs that mention setting up a build environment with lib.exe
  ...

Conflicts:
	doc/ffmpeg.texi
	doc/general.texi
	ffmpeg.c
	libavcodec/Makefile
	libavcodec/dnxhddata.c
	libavformat/mp3enc.c
	libavformat/utils.c
	libavutil/Makefile
	tests/copycooker.sh

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2011-07-09 02:06:40 +02:00

121 lines
4.6 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
/**
* @defgroup dict_api Public Dictionary API
* @{
* 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
* 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
*
* @}
*/
#define AV_DICT_MATCH_CASE 1
#define AV_DICT_IGNORE_SUFFIX 2
#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 chilren. */
#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 {
char *key;
char *value;
} AVDictionaryEntry;
typedef struct AVDictionary AVDictionary;
/**
* Get a dictionary entry with matching key.
*
* @param prev Set to the previous matching element to find the next.
* If set to NULL the first matching element is returned.
* @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);
/**
* Set the given entry in *pm, overwriting an existing entry.
*
* @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 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.
* @return >= 0 on success otherwise an error code <0
*/
int av_dict_set(AVDictionary **pm, const char *key, const char *value, 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
*/
void av_dict_copy(AVDictionary **dst, AVDictionary *src, int flags);
/**
* Free all the memory allocated for an AVDictionary struct
* and all keys and values.
*/
void av_dict_free(AVDictionary **m);
#endif // AVUTIL_DICT_H