mpv/mpvcore/m_property.h

143 lines
5.1 KiB
C

/*
* This file is part of MPlayer.
*
* MPlayer is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPLAYER_M_PROPERTY_H
#define MPLAYER_M_PROPERTY_H
#include <stdbool.h>
#include <stdint.h>
struct m_option;
extern const struct m_option_type m_option_type_dummy;
enum mp_property_action {
// Get the property type. This defines the fundamental data type read from
// or written to the property.
// If unimplemented, the m_option entry that defines the property is used.
// arg: m_option*
M_PROPERTY_GET_TYPE,
// Get the current value.
// arg: pointer to a variable of the type according to the property type
M_PROPERTY_GET,
// Set a new value. The property wrapper will make sure that only valid
// values are set (e.g. according to the property type's min/max range).
// If unimplemented, the property is read-only.
// arg: pointer to a variable of the type according to the property type
M_PROPERTY_SET,
// Get human readable string representing the current value.
// If unimplemented, the property wrapper uses the property type as
// fallback.
// arg: char**
M_PROPERTY_PRINT,
// Switch the property up/down by a given value.
// If unimplemented, the property wrapper uses the property type as
// fallback.
// arg: struct m_property_switch_arg*
M_PROPERTY_SWITCH,
// Get a string containing a parsable representation.
// Can't be overridden by property implementations.
// arg: char**
M_PROPERTY_GET_STRING,
// Set a new value from a string. The property wrapper parses this using the
// parse function provided by the property type.
// Can't be overridden by property implementations.
// arg: char*
M_PROPERTY_SET_STRING,
// Pass down an action to a sub-property.
// arg: struct m_property_action_arg*
M_PROPERTY_KEY_ACTION,
};
// Argument for M_PROPERTY_SWITCH
struct m_property_switch_arg {
double inc; // value to add to property, or cycle direction
bool wrap; // whether value should wrap around on over/underflow
};
// Argument for M_PROPERTY_KEY_ACTION
struct m_property_action_arg {
const char* key;
int action;
void* arg;
};
enum mp_property_return {
// Returned on success.
M_PROPERTY_OK = 1,
// Returned on error.
M_PROPERTY_ERROR = 0,
// Returned when the property can't be used, for example video related
// properties while playing audio only.
M_PROPERTY_UNAVAILABLE = -1,
// Returned if the requested action is not implemented.
M_PROPERTY_NOT_IMPLEMENTED = -2,
// Returned when asking for a property that doesn't exist.
M_PROPERTY_UNKNOWN = -3,
};
// Access a property.
// action: one of m_property_action
// ctx: opaque value passed through to property implementation
// returns: one of mp_property_return
int m_property_do(const struct m_option* prop_list, const char* property_name,
int action, void* arg, void *ctx);
// Print a list of properties.
void m_properties_print_help_list(const struct m_option* list);
// Expand a property string.
// This function allows to print strings containing property values.
// ${NAME} is expanded to the value of property NAME.
// If NAME starts with '=', use the raw value of the property.
// ${NAME:STR} expands to the property, or STR if the property is not
// available.
// ${?NAME:STR} expands to STR if the property is available.
// ${!NAME:STR} expands to STR if the property is not available.
// General syntax: "${" ["?" | "!"] ["="] NAME ":" STR "}"
// STR is recursively expanded using the same rules.
// "$$" can be used to escape "$", and "$}" to escape "}".
// "$>" disables parsing of "$" for the rest of the string.
char* m_properties_expand_string(const struct m_option* prop_list, char *str,
void *ctx);
// Trivial helpers for implementing properties.
int m_property_int_ro(const struct m_option* prop, int action, void* arg,
int var);
int m_property_int64_ro(const struct m_option* prop, int action, void* arg,
int64_t var);
int m_property_float_ro(const struct m_option* prop, int action, void* arg,
float var);
int m_property_double_ro(const struct m_option* prop, int action, void* arg,
double var);
int m_property_strdup_ro(const struct m_option* prop, int action, void* arg,
const char *var);
#endif /* MPLAYER_M_PROPERTY_H */