diff -r c4fd2813b127 -r d92eeb468dad misc/winutils/include/libavutil/opt.h --- a/misc/winutils/include/libavutil/opt.h Wed Jul 31 23:14:27 2019 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,592 +0,0 @@ -/* - * AVOptions - * copyright (c) 2005 Michael Niedermayer - * - * This file is part of Libav. - * - * Libav 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. - * - * Libav 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 Libav; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#ifndef AVUTIL_OPT_H -#define AVUTIL_OPT_H - -/** - * @file - * AVOptions - */ - -#include "rational.h" -#include "avutil.h" -#include "dict.h" -#include "log.h" - -/** - * @defgroup avoptions AVOptions - * @ingroup lavu_data - * @{ - * AVOptions provide a generic system to declare options on arbitrary structs - * ("objects"). An option can have a help text, a type and a range of possible - * values. Options may then be enumerated, read and written to. - * - * @section avoptions_implement Implementing AVOptions - * This section describes how to add AVOptions capabilities to a struct. - * - * All AVOptions-related information is stored in an AVClass. Therefore - * the first member of the struct must be a pointer to an AVClass describing it. - * The option field of the AVClass must be set to a NULL-terminated static array - * of AVOptions. Each AVOption must have a non-empty name, a type, a default - * value and for number-type AVOptions also a range of allowed values. It must - * also declare an offset in bytes from the start of the struct, where the field - * associated with this AVOption is located. Other fields in the AVOption struct - * should also be set when applicable, but are not required. - * - * The following example illustrates an AVOptions-enabled struct: - * @code - * typedef struct test_struct { - * AVClass *class; - * int int_opt; - * char *str_opt; - * uint8_t *bin_opt; - * int bin_len; - * } test_struct; - * - * static const AVOption options[] = { - * { "test_int", "This is a test option of int type.", offsetof(test_struct, int_opt), - * AV_OPT_TYPE_INT, { .i64 = -1 }, INT_MIN, INT_MAX }, - * { "test_str", "This is a test option of string type.", offsetof(test_struct, str_opt), - * AV_OPT_TYPE_STRING }, - * { "test_bin", "This is a test option of binary type.", offsetof(test_struct, bin_opt), - * AV_OPT_TYPE_BINARY }, - * { NULL }, - * }; - * - * static const AVClass test_class = { - * .class_name = "test class", - * .item_name = av_default_item_name, - * .option = options, - * .version = LIBAVUTIL_VERSION_INT, - * }; - * @endcode - * - * Next, when allocating your struct, you must ensure that the AVClass pointer - * is set to the correct value. Then, av_opt_set_defaults() must be called to - * initialize defaults. After that the struct is ready to be used with the - * AVOptions API. - * - * When cleaning up, you may use the av_opt_free() function to automatically - * free all the allocated string and binary options. - * - * Continuing with the above example: - * - * @code - * test_struct *alloc_test_struct(void) - * { - * test_struct *ret = av_malloc(sizeof(*ret)); - * ret->class = &test_class; - * av_opt_set_defaults(ret); - * return ret; - * } - * void free_test_struct(test_struct **foo) - * { - * av_opt_free(*foo); - * av_freep(foo); - * } - * @endcode - * - * @subsection avoptions_implement_nesting Nesting - * It may happen that an AVOptions-enabled struct contains another - * AVOptions-enabled struct as a member (e.g. AVCodecContext in - * libavcodec exports generic options, while its priv_data field exports - * codec-specific options). In such a case, it is possible to set up the - * parent struct to export a child's options. To do that, simply - * implement AVClass.child_next() and AVClass.child_class_next() in the - * parent struct's AVClass. - * Assuming that the test_struct from above now also contains a - * child_struct field: - * - * @code - * typedef struct child_struct { - * AVClass *class; - * int flags_opt; - * } child_struct; - * static const AVOption child_opts[] = { - * { "test_flags", "This is a test option of flags type.", - * offsetof(child_struct, flags_opt), AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT_MIN, INT_MAX }, - * { NULL }, - * }; - * static const AVClass child_class = { - * .class_name = "child class", - * .item_name = av_default_item_name, - * .option = child_opts, - * .version = LIBAVUTIL_VERSION_INT, - * }; - * - * void *child_next(void *obj, void *prev) - * { - * test_struct *t = obj; - * if (!prev && t->child_struct) - * return t->child_struct; - * return NULL - * } - * const AVClass child_class_next(const AVClass *prev) - * { - * return prev ? NULL : &child_class; - * } - * @endcode - * Putting child_next() and child_class_next() as defined above into - * test_class will now make child_struct's options accessible through - * test_struct (again, proper setup as described above needs to be done on - * child_struct right after it is created). - * - * From the above example it might not be clear why both child_next() - * and child_class_next() are needed. The distinction is that child_next() - * iterates over actually existing objects, while child_class_next() - * iterates over all possible child classes. E.g. if an AVCodecContext - * was initialized to use a codec which has private options, then its - * child_next() will return AVCodecContext.priv_data and finish - * iterating. OTOH child_class_next() on AVCodecContext.av_class will - * iterate over all available codecs with private options. - * - * @subsection avoptions_implement_named_constants Named constants - * It is possible to create named constants for options. Simply set the unit - * field of the option the constants should apply to to a string and - * create the constants themselves as options of type AV_OPT_TYPE_CONST - * with their unit field set to the same string. - * Their default_val field should contain the value of the named - * constant. - * For example, to add some named constants for the test_flags option - * above, put the following into the child_opts array: - * @code - * { "test_flags", "This is a test option of flags type.", - * offsetof(child_struct, flags_opt), AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT_MIN, INT_MAX, "test_unit" }, - * { "flag1", "This is a flag with value 16", 0, AV_OPT_TYPE_CONST, { .i64 = 16 }, 0, 0, "test_unit" }, - * @endcode - * - * @section avoptions_use Using AVOptions - * This section deals with accessing options in an AVOptions-enabled struct. - * Such structs in Libav are e.g. AVCodecContext in libavcodec or - * AVFormatContext in libavformat. - * - * @subsection avoptions_use_examine Examining AVOptions - * The basic functions for examining options are av_opt_next(), which iterates - * over all options defined for one object, and av_opt_find(), which searches - * for an option with the given name. - * - * The situation is more complicated with nesting. An AVOptions-enabled struct - * may have AVOptions-enabled children. Passing the AV_OPT_SEARCH_CHILDREN flag - * to av_opt_find() will make the function search children recursively. - * - * For enumerating there are basically two cases. The first is when you want to - * get all options that may potentially exist on the struct and its children - * (e.g. when constructing documentation). In that case you should call - * av_opt_child_class_next() recursively on the parent struct's AVClass. The - * second case is when you have an already initialized struct with all its - * children and you want to get all options that can be actually written or read - * from it. In that case you should call av_opt_child_next() recursively (and - * av_opt_next() on each result). - * - * @subsection avoptions_use_get_set Reading and writing AVOptions - * When setting options, you often have a string read directly from the - * user. In such a case, simply passing it to av_opt_set() is enough. For - * non-string type options, av_opt_set() will parse the string according to the - * option type. - * - * Similarly av_opt_get() will read any option type and convert it to a string - * which will be returned. Do not forget that the string is allocated, so you - * have to free it with av_free(). - * - * In some cases it may be more convenient to put all options into an - * AVDictionary and call av_opt_set_dict() on it. A specific case of this - * are the format/codec open functions in lavf/lavc which take a dictionary - * filled with option as a parameter. This allows to set some options - * that cannot be set otherwise, since e.g. the input file format is not known - * before the file is actually opened. - */ - -enum AVOptionType{ - AV_OPT_TYPE_FLAGS, - AV_OPT_TYPE_INT, - AV_OPT_TYPE_INT64, - AV_OPT_TYPE_DOUBLE, - AV_OPT_TYPE_FLOAT, - AV_OPT_TYPE_STRING, - AV_OPT_TYPE_RATIONAL, - AV_OPT_TYPE_BINARY, ///< offset must point to a pointer immediately followed by an int for the length - AV_OPT_TYPE_CONST = 128, -#if FF_API_OLD_AVOPTIONS - FF_OPT_TYPE_FLAGS = 0, - FF_OPT_TYPE_INT, - FF_OPT_TYPE_INT64, - FF_OPT_TYPE_DOUBLE, - FF_OPT_TYPE_FLOAT, - FF_OPT_TYPE_STRING, - FF_OPT_TYPE_RATIONAL, - FF_OPT_TYPE_BINARY, ///< offset must point to a pointer immediately followed by an int for the length - FF_OPT_TYPE_CONST=128, -#endif -}; - -/** - * AVOption - */ -typedef struct AVOption { - const char *name; - - /** - * short English help text - * @todo What about other languages? - */ - const char *help; - - /** - * The offset relative to the context structure where the option - * value is stored. It should be 0 for named constants. - */ - int offset; - enum AVOptionType type; - - /** - * the default value for scalar options - */ - union { - int64_t i64; - double dbl; - const char *str; - /* TODO those are unused now */ - AVRational q; - } default_val; - double min; ///< minimum valid value for the option - double max; ///< maximum valid value for the option - - int flags; -#define AV_OPT_FLAG_ENCODING_PARAM 1 ///< a generic parameter which can be set by the user for muxing or encoding -#define AV_OPT_FLAG_DECODING_PARAM 2 ///< a generic parameter which can be set by the user for demuxing or decoding -#define AV_OPT_FLAG_METADATA 4 ///< some data extracted or inserted into the file like title, comment, ... -#define AV_OPT_FLAG_AUDIO_PARAM 8 -#define AV_OPT_FLAG_VIDEO_PARAM 16 -#define AV_OPT_FLAG_SUBTITLE_PARAM 32 -//FIXME think about enc-audio, ... style flags - - /** - * The logical unit to which the option belongs. Non-constant - * options and corresponding named constants share the same - * unit. May be NULL. - */ - const char *unit; -} AVOption; - -#if FF_API_FIND_OPT -/** - * Look for an option in obj. Look only for the options which - * have the flags set as specified in mask and flags (that is, - * for which it is the case that opt->flags & mask == flags). - * - * @param[in] obj a pointer to a struct whose first element is a - * pointer to an AVClass - * @param[in] name the name of the option to look for - * @param[in] unit the unit of the option to look for, or any if NULL - * @return a pointer to the option found, or NULL if no option - * has been found - * - * @deprecated use av_opt_find. - */ -attribute_deprecated -const AVOption *av_find_opt(void *obj, const char *name, const char *unit, int mask, int flags); -#endif - -#if FF_API_OLD_AVOPTIONS -/** - * Set the field of obj with the given name to value. - * - * @param[in] obj A struct whose first element is a pointer to an - * AVClass. - * @param[in] name the name of the field to set - * @param[in] val The value to set. If the field is not of a string - * type, then the given string is parsed. - * SI postfixes and some named scalars are supported. - * If the field is of a numeric type, it has to be a numeric or named - * scalar. Behavior with more than one scalar and +- infix operators - * is undefined. - * If the field is of a flags type, it has to be a sequence of numeric - * scalars or named flags separated by '+' or '-'. Prefixing a flag - * with '+' causes it to be set without affecting the other flags; - * similarly, '-' unsets a flag. - * @param[out] o_out if non-NULL put here a pointer to the AVOption - * found - * @param alloc this parameter is currently ignored - * @return 0 if the value has been set, or an AVERROR code in case of - * error: - * AVERROR_OPTION_NOT_FOUND if no matching option exists - * AVERROR(ERANGE) if the value is out of range - * AVERROR(EINVAL) if the value is not valid - * @deprecated use av_opt_set() - */ -attribute_deprecated -int av_set_string3(void *obj, const char *name, const char *val, int alloc, const AVOption **o_out); - -attribute_deprecated const AVOption *av_set_double(void *obj, const char *name, double n); -attribute_deprecated const AVOption *av_set_q(void *obj, const char *name, AVRational n); -attribute_deprecated const AVOption *av_set_int(void *obj, const char *name, int64_t n); - -attribute_deprecated double av_get_double(void *obj, const char *name, const AVOption **o_out); -attribute_deprecated AVRational av_get_q(void *obj, const char *name, const AVOption **o_out); -attribute_deprecated int64_t av_get_int(void *obj, const char *name, const AVOption **o_out); -attribute_deprecated const char *av_get_string(void *obj, const char *name, const AVOption **o_out, char *buf, int buf_len); -attribute_deprecated const AVOption *av_next_option(void *obj, const AVOption *last); -#endif - -/** - * Show the obj options. - * - * @param req_flags requested flags for the options to show. Show only the - * options for which it is opt->flags & req_flags. - * @param rej_flags rejected flags for the options to show. Show only the - * options for which it is !(opt->flags & req_flags). - * @param av_log_obj log context to use for showing the options - */ -int av_opt_show2(void *obj, void *av_log_obj, int req_flags, int rej_flags); - -/** - * Set the values of all AVOption fields to their default values. - * - * @param s an AVOption-enabled struct (its first member must be a pointer to AVClass) - */ -void av_opt_set_defaults(void *s); - -#if FF_API_OLD_AVOPTIONS -attribute_deprecated -void av_opt_set_defaults2(void *s, int mask, int flags); -#endif - -/** - * Parse the key/value pairs list in opts. For each key/value pair - * found, stores the value in the field in ctx that is named like the - * key. ctx must be an AVClass context, storing is done using - * AVOptions. - * - * @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 - * @return the number of successfully set key/value pairs, or a negative - * value corresponding to an AVERROR code in case of error: - * AVERROR(EINVAL) if opts cannot be parsed, - * the error code issued by av_set_string3() if a key/value pair - * cannot be set - */ -int av_set_options_string(void *ctx, const char *opts, - const char *key_val_sep, const char *pairs_sep); - -/** - * Free all string and binary options in obj. - */ -void av_opt_free(void *obj); - -/** - * Check whether a particular flag is set in a flags field. - * - * @param field_name the name of the flag field option - * @param flag_name the name of the flag to check - * @return non-zero if the flag is set, zero if the flag isn't set, - * isn't of the right type, or the flags field doesn't exist. - */ -int av_opt_flag_is_set(void *obj, const char *field_name, const char *flag_name); - -/* - * Set all the options from a given dictionary on an object. - * - * @param obj a struct whose first element is a pointer to AVClass - * @param options options to process. This dictionary will be freed and replaced - * by a new one containing all options not found in obj. - * Of course this new dictionary needs to be freed by caller - * with av_dict_free(). - * - * @return 0 on success, a negative AVERROR if some option was found in obj, - * but could not be set. - * - * @see av_dict_copy() - */ -int av_opt_set_dict(void *obj, struct AVDictionary **options); - -/** - * @defgroup opt_eval_funcs Evaluating option strings - * @{ - * This group of functions can be used to evaluate option strings - * and get numbers out of them. They do the same thing as av_opt_set(), - * except the result is written into the caller-supplied pointer. - * - * @param obj a struct whose first element is a pointer to AVClass. - * @param o an option for which the string is to be evaluated. - * @param val string to be evaluated. - * @param *_out value of the string will be written here. - * - * @return 0 on success, a negative number on failure. - */ -int av_opt_eval_flags (void *obj, const AVOption *o, const char *val, int *flags_out); -int av_opt_eval_int (void *obj, const AVOption *o, const char *val, int *int_out); -int av_opt_eval_int64 (void *obj, const AVOption *o, const char *val, int64_t *int64_out); -int av_opt_eval_float (void *obj, const AVOption *o, const char *val, float *float_out); -int av_opt_eval_double(void *obj, const AVOption *o, const char *val, double *double_out); -int av_opt_eval_q (void *obj, const AVOption *o, const char *val, AVRational *q_out); -/** - * @} - */ - -#define AV_OPT_SEARCH_CHILDREN 0x0001 /**< Search in possible children of the - given object first. */ -/** - * The obj passed to av_opt_find() is fake -- only a double pointer to AVClass - * instead of a required pointer to a struct containing AVClass. This is - * useful for searching for options without needing to allocate the corresponding - * object. - */ -#define AV_OPT_SEARCH_FAKE_OBJ 0x0002 - -/** - * Look for an option in an object. Consider only options which - * have all the specified flags set. - * - * @param[in] obj A pointer to a struct whose first element is a - * pointer to an AVClass. - * Alternatively a double pointer to an AVClass, if - * AV_OPT_SEARCH_FAKE_OBJ search flag is set. - * @param[in] name The name of the option to look for. - * @param[in] unit When searching for named constants, name of the unit - * it belongs to. - * @param opt_flags Find only options with all the specified flags set (AV_OPT_FLAG). - * @param search_flags A combination of AV_OPT_SEARCH_*. - * - * @return A pointer to the option found, or NULL if no option - * was found. - * - * @note Options found with AV_OPT_SEARCH_CHILDREN flag may not be settable - * directly with av_set_string3(). Use special calls which take an options - * AVDictionary (e.g. avformat_open_input()) to set options found with this - * flag. - */ -const AVOption *av_opt_find(void *obj, const char *name, const char *unit, - int opt_flags, int search_flags); - -/** - * Look for an option in an object. Consider only options which - * have all the specified flags set. - * - * @param[in] obj A pointer to a struct whose first element is a - * pointer to an AVClass. - * Alternatively a double pointer to an AVClass, if - * AV_OPT_SEARCH_FAKE_OBJ search flag is set. - * @param[in] name The name of the option to look for. - * @param[in] unit When searching for named constants, name of the unit - * it belongs to. - * @param opt_flags Find only options with all the specified flags set (AV_OPT_FLAG). - * @param search_flags A combination of AV_OPT_SEARCH_*. - * @param[out] target_obj if non-NULL, an object to which the option belongs will be - * written here. It may be different from obj if AV_OPT_SEARCH_CHILDREN is present - * in search_flags. This parameter is ignored if search_flags contain - * AV_OPT_SEARCH_FAKE_OBJ. - * - * @return A pointer to the option found, or NULL if no option - * was found. - */ -const AVOption *av_opt_find2(void *obj, const char *name, const char *unit, - int opt_flags, int search_flags, void **target_obj); - -/** - * Iterate over all AVOptions belonging to obj. - * - * @param obj an AVOptions-enabled struct or a double pointer to an - * AVClass describing it. - * @param prev result of the previous call to av_opt_next() on this object - * or NULL - * @return next AVOption or NULL - */ -const AVOption *av_opt_next(void *obj, const AVOption *prev); - -/** - * Iterate over AVOptions-enabled children of obj. - * - * @param prev result of a previous call to this function or NULL - * @return next AVOptions-enabled child or NULL - */ -void *av_opt_child_next(void *obj, void *prev); - -/** - * Iterate over potential AVOptions-enabled children of parent. - * - * @param prev result of a previous call to this function or NULL - * @return AVClass corresponding to next potential child or NULL - */ -const AVClass *av_opt_child_class_next(const AVClass *parent, const AVClass *prev); - -/** - * @defgroup opt_set_funcs Option setting functions - * @{ - * Those functions set the field of obj with the given name to value. - * - * @param[in] obj A struct whose first element is a pointer to an AVClass. - * @param[in] name the name of the field to set - * @param[in] val The value to set. In case of av_opt_set() if the field is not - * of a string type, then the given string is parsed. - * SI postfixes and some named scalars are supported. - * If the field is of a numeric type, it has to be a numeric or named - * scalar. Behavior with more than one scalar and +- infix operators - * is undefined. - * If the field is of a flags type, it has to be a sequence of numeric - * scalars or named flags separated by '+' or '-'. Prefixing a flag - * with '+' causes it to be set without affecting the other flags; - * similarly, '-' unsets a flag. - * @param search_flags flags passed to av_opt_find2. I.e. if AV_OPT_SEARCH_CHILDREN - * is passed here, then the option may be set on a child of obj. - * - * @return 0 if the value has been set, or an AVERROR code in case of - * error: - * AVERROR_OPTION_NOT_FOUND if no matching option exists - * AVERROR(ERANGE) if the value is out of range - * AVERROR(EINVAL) if the value is not valid - */ -int av_opt_set (void *obj, const char *name, const char *val, int search_flags); -int av_opt_set_int (void *obj, const char *name, int64_t val, int search_flags); -int av_opt_set_double(void *obj, const char *name, double val, int search_flags); -int av_opt_set_q (void *obj, const char *name, AVRational val, int search_flags); -int av_opt_set_bin (void *obj, const char *name, const uint8_t *val, int size, int search_flags); -/** - * @} - */ - -/** - * @defgroup opt_get_funcs Option getting functions - * @{ - * Those functions get a value of the option with the given name from an object. - * - * @param[in] obj a struct whose first element is a pointer to an AVClass. - * @param[in] name name of the option to get. - * @param[in] search_flags flags passed to av_opt_find2. I.e. if AV_OPT_SEARCH_CHILDREN - * is passed here, then the option may be found in a child of obj. - * @param[out] out_val value of the option will be written here - * @return 0 on success, a negative error code otherwise - */ -/** - * @note the returned string will av_malloc()ed and must be av_free()ed by the caller - */ -int av_opt_get (void *obj, const char *name, int search_flags, uint8_t **out_val); -int av_opt_get_int (void *obj, const char *name, int search_flags, int64_t *out_val); -int av_opt_get_double(void *obj, const char *name, int search_flags, double *out_val); -int av_opt_get_q (void *obj, const char *name, int search_flags, AVRational *out_val); -/** - * @} - * @} - */ - -#endif /* AVUTIL_OPT_H */