variables.h

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/*****************************************************************************
 * variables.h: object variables typedefs
 *****************************************************************************
 * Copyright (C) 1999-2012 VLC authors and VideoLAN
 *
 * Authors: Samuel Hocevar <sam@zoy.org>
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

#ifndef LIBVLC_VARIABLES_H
# define LIBVLC_VARIABLES_H 1

# include <vlc_atomic.h>

/**
 * Private LibVLC data for each object.
 */
typedef struct vlc_object_internals vlc_object_internals_t;

struct vlc_object_internals
{
    char           *psz_name; /* given name */

    /* Object variables */
    void           *var_root;
    vlc_mutex_t     var_lock;
    vlc_cond_t      var_wait;

    /* Objects thread synchronization */
    int             pipes[2];
    atomic_bool     alive;

    /* Objects management */
    atomic_uint     refs;
    vlc_destructor_t pf_destructor;

    /* Objects tree structure */
    vlc_object_internals_t *next;  /* next sibling */
    vlc_object_internals_t *prev;  /* previous sibling */
    vlc_object_internals_t *first; /* first child */
};

# define vlc_internals( obj ) (((vlc_object_internals_t*)(VLC_OBJECT(obj)))-1)
# define vlc_externals( priv ) ((vlc_object_t *)((priv) + 1))


typedef struct callback_entry_t callback_entry_t;

typedef struct variable_ops_t
{
    int  (*pf_cmp) ( vlc_value_t, vlc_value_t );
    void (*pf_dup) ( vlc_value_t * );
    void (*pf_free) ( vlc_value_t * );
} variable_ops_t;

/**
 * The structure describing a variable.
 * \note vlc_value_t is the common union for variable values
 */
struct variable_t
{
    char *       psz_name; /**< The variable unique name (must be first) */

    /** The variable's exported value */
    vlc_value_t  val;

    /** The variable display name, mainly for use by the interfaces */
    char *       psz_text;

    const variable_ops_t *ops;

    int          i_type;   /**< The type of the variable */
    unsigned     i_usage;  /**< Reference count */

    /** If the variable has min/max/step values */
    vlc_value_t  min, max, step;

    /** Index of the default choice, if the variable is to be chosen in
     * a list */
    int          i_default;
    /** List of choices */
    vlc_list_t   choices;
    /** List of friendly names for the choices */
    vlc_list_t   choices_text;

    /** Set to TRUE if the variable is in a callback */
    bool   b_incallback;

    /** Number of registered callbacks */
    int                i_entries;
    /** Array of registered callbacks */
    callback_entry_t * p_entries;
};

extern void var_DestroyAll( vlc_object_t * );

#endif