mirror of
https://github.com/librempeg/librempeg
synced 2024-11-23 11:39:47 +00:00
d2af7205a1
eval API. More grep-friendly and more consistent with the rest of the FFmpeg API. Originally committed as revision 25708 to svn://svn.ffmpeg.org/ffmpeg/trunk
147 lines
6.4 KiB
C
147 lines
6.4 KiB
C
/*
|
|
* Copyright (c) 2002 Michael Niedermayer <michaelni@gmx.at>
|
|
*
|
|
* 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
|
|
* simple arithmetic expression evaluator
|
|
*/
|
|
|
|
#ifndef AVUTIL_EVAL_H
|
|
#define AVUTIL_EVAL_H
|
|
|
|
#include "avutil.h"
|
|
|
|
typedef struct AVExpr AVExpr;
|
|
|
|
/**
|
|
* Parse and evaluate an expression.
|
|
* Note, this is significantly slower than av_expr_eval().
|
|
*
|
|
* @param res a pointer to a double where is put the result value of
|
|
* the expression, or NAN in case of error
|
|
* @param s expression as a zero terminated string, for example "1+2^3+5*5+sin(2/3)"
|
|
* @param const_names NULL terminated array of zero terminated strings of constant identifiers, for example {"PI", "E", 0}
|
|
* @param const_values a zero terminated array of values for the identifiers from const_names
|
|
* @param func1_names NULL terminated array of zero terminated strings of funcs1 identifiers
|
|
* @param funcs1 NULL terminated array of function pointers for functions which take 1 argument
|
|
* @param func2_names NULL terminated array of zero terminated strings of funcs2 identifiers
|
|
* @param funcs2 NULL terminated array of function pointers for functions which take 2 arguments
|
|
* @param opaque a pointer which will be passed to all functions from funcs1 and funcs2
|
|
* @param log_ctx parent logging context
|
|
* @return 0 in case of success, a negative value corresponding to an
|
|
* AVERROR code otherwise
|
|
*/
|
|
int av_expr_parse_and_eval(double *res, const char *s,
|
|
const char * const *const_names, const double *const_values,
|
|
const char * const *func1_names, double (* const *funcs1)(void *, double),
|
|
const char * const *func2_names, double (* const *funcs2)(void *, double, double),
|
|
void *opaque, int log_offset, void *log_ctx);
|
|
|
|
/**
|
|
* Parse an expression.
|
|
*
|
|
* @param expr a pointer where is put an AVExpr containing the parsed
|
|
* value in case of successfull parsing, or NULL otherwise.
|
|
* The pointed to AVExpr must be freed with av_expr_free() by the user
|
|
* when it is not needed anymore.
|
|
* @param s expression as a zero terminated string, for example "1+2^3+5*5+sin(2/3)"
|
|
* @param const_names NULL terminated array of zero terminated strings of constant identifiers, for example {"PI", "E", 0}
|
|
* @param func1_names NULL terminated array of zero terminated strings of funcs1 identifiers
|
|
* @param funcs1 NULL terminated array of function pointers for functions which take 1 argument
|
|
* @param func2_names NULL terminated array of zero terminated strings of funcs2 identifiers
|
|
* @param funcs2 NULL terminated array of function pointers for functions which take 2 arguments
|
|
* @param log_ctx parent logging context
|
|
* @return 0 in case of success, a negative value corresponding to an
|
|
* AVERROR code otherwise
|
|
*/
|
|
int av_expr_parse(AVExpr **expr, const char *s,
|
|
const char * const *const_names,
|
|
const char * const *func1_names, double (* const *funcs1)(void *, double),
|
|
const char * const *func2_names, double (* const *funcs2)(void *, double, double),
|
|
int log_offset, void *log_ctx);
|
|
|
|
/**
|
|
* Evaluate a previously parsed expression.
|
|
*
|
|
* @param const_values a zero terminated array of values for the identifiers from av_expr_parse() const_names
|
|
* @param opaque a pointer which will be passed to all functions from funcs1 and funcs2
|
|
* @return the value of the expression
|
|
*/
|
|
double av_expr_eval(AVExpr *e, const double *const_values, void *opaque);
|
|
|
|
/**
|
|
* Free a parsed expression previously created with av_expr_parse().
|
|
*/
|
|
void av_expr_free(AVExpr *e);
|
|
|
|
#if FF_API_OLD_EVAL_NAMES
|
|
/**
|
|
* @deprecated Deprecated in favor of av_expr_parse_and_eval().
|
|
*/
|
|
attribute_deprecated
|
|
int av_parse_and_eval_expr(double *res, const char *s,
|
|
const char * const *const_names, const double *const_values,
|
|
const char * const *func1_names, double (* const *funcs1)(void *, double),
|
|
const char * const *func2_names, double (* const *funcs2)(void *, double, double),
|
|
void *opaque, int log_offset, void *log_ctx);
|
|
|
|
/**
|
|
* @deprecated Deprecated in favor of av_expr_parse().
|
|
*/
|
|
attribute_deprecated
|
|
int av_parse_expr(AVExpr **expr, const char *s,
|
|
const char * const *const_names,
|
|
const char * const *func1_names, double (* const *funcs1)(void *, double),
|
|
const char * const *func2_names, double (* const *funcs2)(void *, double, double),
|
|
int log_offset, void *log_ctx);
|
|
/**
|
|
* @deprecated Deprecated in favor of av_expr_eval().
|
|
*/
|
|
attribute_deprecated
|
|
double av_eval_expr(AVExpr *e, const double *const_values, void *opaque);
|
|
|
|
/**
|
|
* @deprecated Deprecated in favor of av_expr_free().
|
|
*/
|
|
attribute_deprecated
|
|
void av_free_expr(AVExpr *e);
|
|
#endif /* FF_API_OLD_EVAL_NAMES */
|
|
|
|
/**
|
|
* Parse the string in numstr and return its value as a double. If
|
|
* the string is empty, contains only whitespaces, or does not contain
|
|
* an initial substring that has the expected syntax for a
|
|
* floating-point number, no conversion is performed. In this case,
|
|
* returns a value of zero and the value returned in tail is the value
|
|
* of numstr.
|
|
*
|
|
* @param numstr a string representing a number, may contain one of
|
|
* the International System number postfixes, for example 'K', 'M',
|
|
* 'G'. If 'i' is appended after the postfix, powers of 2 are used
|
|
* instead of powers of 10. The 'B' postfix multiplies the value for
|
|
* 8, and can be appended after another postfix or used alone. This
|
|
* allows using for example 'KB', 'MiB', 'G' and 'B' as postfix.
|
|
* @param tail if non-NULL puts here the pointer to the char next
|
|
* after the last parsed character
|
|
*/
|
|
double av_strtod(const char *numstr, char **tail);
|
|
|
|
#endif /* AVUTIL_EVAL_H */
|