mpv/options/m_property.h

222 lines
8.1 KiB
C

/*
* This file is part of mpv.
*
* mpv 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.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef MPLAYER_M_PROPERTY_H
#define MPLAYER_M_PROPERTY_H
#include <stdbool.h>
#include <stdint.h>
#include "m_option.h"
struct mp_log;
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,
// Like M_PROPERTY_GET_TYPE, but get a type that is compatible to the real
// type, but reflect practical limits, such as runtime-available values.
// This is mostly used for "UI" related things.
// (Example: volume property.)
M_PROPERTY_GET_CONSTRICTED_TYPE,
// 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 parseable 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,
// Set a mpv_node value.
// arg: mpv_node*
M_PROPERTY_GET_NODE,
// Get a mpv_node value.
// arg: mpv_node*
M_PROPERTY_SET_NODE,
// Pass down an action to a sub-property.
// arg: struct m_property_action_arg*
M_PROPERTY_KEY_ACTION,
// Get the (usually constant) value that indicates no change. Obscure
// special functionality for things like the volume property.
// Otherwise works like M_PROPERTY_GET.
M_PROPERTY_GET_NEUTRAL,
};
// 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,
// When trying to set invalid or incorrectly formatted data.
M_PROPERTY_INVALID_FORMAT = -4,
};
struct m_property {
const char *name;
// ctx: opaque caller context, which the property might use
// prop: pointer to this struct
// action: one of enum mp_property_action
// arg: specific to the action
// returns: one of enum mp_property_return
int (*call)(void *ctx, struct m_property *prop, int action, void *arg);
void *priv;
};
struct m_property *m_property_list_find(const struct m_property *list,
const char *name);
// 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(struct mp_log *log, const struct m_property* prop_list,
const char* property_name, int action, void* arg, void *ctx);
// Given a path of the form "a/b/c", this function will set *prefix to "a",
// and rem to "b/c", and return true.
// If there is no '/' in the path, set prefix to path, and rem to "", and
// return false.
bool m_property_split_path(const char *path, bstr *prefix, char **rem);
// Print a list of properties.
void m_properties_print_help_list(struct mp_log *log,
const struct m_property *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_property *prop_list,
const char *str, void *ctx);
// Trivial helpers for implementing properties.
int m_property_flag_ro(int action, void* arg, int var);
int m_property_int_ro(int action, void* arg, int var);
int m_property_int64_ro(int action, void* arg, int64_t var);
int m_property_float_ro(int action, void* arg, float var);
int m_property_double_ro(int action, void* arg, double var);
int m_property_strdup_ro(int action, void* arg, const char *var);
struct m_sub_property {
// Name of the sub-property - this will be prefixed with the parent
// property's name.
const char *name;
// Type of the data stored in the value member. See m_option.
struct m_option type;
// Data returned by the sub-property. m_property_read_sub() will make a
// copy of this if needed. It will never write or free the data.
union m_option_value value;
// This can be set to true if the property should be hidden.
bool unavailable;
};
// Convenience macros which can be used as part of a sub_property entry.
#define SUB_PROP_INT(i) \
.type = {.type = CONF_TYPE_INT}, .value = {.int_ = (i)}
#define SUB_PROP_INT64(i) \
.type = {.type = CONF_TYPE_INT64}, .value = {.int64 = (i)}
#define SUB_PROP_STR(s) \
.type = {.type = CONF_TYPE_STRING}, .value = {.string = (char *)(s)}
#define SUB_PROP_FLOAT(f) \
.type = {.type = CONF_TYPE_FLOAT}, .value = {.float_ = (f)}
#define SUB_PROP_DOUBLE(f) \
.type = {.type = CONF_TYPE_DOUBLE}, .value = {.double_ = (f)}
#define SUB_PROP_FLAG(f) \
.type = {.type = CONF_TYPE_FLAG}, .value = {.flag = (f)}
int m_property_read_sub(const struct m_sub_property *props, int action, void *arg);
// Used with m_property_read_list().
// Get an entry. item is the 0-based index of the item. This behaves like a
// top-level property request (but you must implement M_PROPERTY_GET_TYPE).
// item will be in range [0, count), for count see m_property_read_list()
// action, arg are for property access.
// ctx is userdata passed to m_property_read_list.
typedef int (*m_get_item_cb)(int item, int action, void *arg, void *ctx);
int m_property_read_list(int action, void *arg, int count,
m_get_item_cb get_item, void *ctx);
#endif /* MPLAYER_M_PROPERTY_H */