mpv/core/m_struct.h

113 lines
3.3 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_STRUCT_H
#define MPLAYER_M_STRUCT_H
#include <stddef.h>
#include <inttypes.h>
#include "core/bstr.h"
/// \defgroup OptionsStruct Options struct
/// \ingroup Options
/// An API to manipulate structs using m_option.
///@{
/// \file m_struct.h
struct m_option;
/// Struct definition
typedef struct m_struct_st {
/// For error messages and debugging
const char* name;
/// size of the whole struct
unsigned int size;
/// Pointer to a struct filled with the default settings
const void* defaults;
/// Field list.
/** The p field of the \ref m_option struct must contain the offset
* of the member in the struct (use M_ST_OFF macro for this).
*/
const struct m_option* fields;
} m_struct_t;
/// Get the offset of a struct field.
/** \param struct_type Struct type.
* \param member Name of the field.
* \return The offset of the field in bytes.
*/
#define M_ST_OFF (void *)(uintptr_t)offsetof
/// Get a pointer to a struct field.
/** \param struct_p Pointer to the struct.
* \param struct_offset Offset of the field in the struct.
* \return Pointer to the struct field.
*/
#define M_ST_MB_P(struct_p, struct_offset) \
((void *)((char *)(struct_p) + (uintptr_t)(struct_offset)))
/// Access a struct field at a given offset.
/** \param member_type Type of the field.
* \param struct_p Pointer to the struct.
* \param struct_offset Offset of the field in the struct.
* \return The struct field at the given offset.
*/
#define M_ST_MB(member_type, struct_p, struct_offset) \
(*(member_type*) M_ST_MB_P ((struct_p), (struct_offset)))
/// Allocate the struct and set it to the defaults.
/** \param st Struct definition.
* \return The newly allocated object set to default.
*/
void*
m_struct_alloc(const m_struct_t* st);
/// Set a field of the struct.
/** \param st Struct definition.
* \param obj Pointer to the struct to set.
* \param field Name of the field to set.
* \param param New value of the field.
* \return 0 on error, 1 on success.
*/
int m_struct_set(const m_struct_t *st, void *obj, const char *field,
struct bstr param);
/// Free an allocated struct.
/** \param st Struct definition.
* \param obj Pointer to the struct to copy.
*/
void
m_struct_free(const m_struct_t* st, void* obj);
/// Get a field description.
/** \param st Struct definition.
* \param f Name of the field.
* \return The \ref m_option struct describing the field or NULL if not found.
*/
const struct m_option*
m_struct_get_field(const m_struct_t* st,const char* f);
///@}
#endif /* MPLAYER_M_STRUCT_H */