include/variables.h

   1 /*****************************************************************************
   2  * variables.h: variables handling
   3  *****************************************************************************
   4  * Copyright (C) 2002-2004 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Samuel Hocevar <sam@zoy.org>
   8  *          Gildas Bazin <gbazin@netcourrier.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /**
  26  * \defgroup variables Variables
  27  *
  28  * Functions for using the object variables in vlc.
  29  *
  30  * Vlc have a very powerful "object variable" infrastructure useful
  31  * for many things.
  32  *
  33  * @{
  34  */
  35
  36 typedef struct callback_entry_t callback_entry_t;
  37
  38 /**
  39  * The structure describing a variable.
  40  * \note vlc_value_t is the common union for variable values
  41  */
  42 struct variable_t
  43 {
  44     /** The variable's exported value */
  45     vlc_value_t  val;
  46
  47     char *       psz_name; /**< The variable unique name */
  48     uint32_t     i_hash;   /**< (almost) unique hashed value */
  49     int          i_type;   /**< The type of the variable */
  50
  51     /** The variable display name, mainly for use by the interfaces */
  52     char *       psz_text;
  53
  54     /** A pointer to a comparison function */
  55     int      ( * pf_cmp ) ( vlc_value_t, vlc_value_t );
  56     /** A pointer to a duplication function */
  57     void     ( * pf_dup ) ( vlc_value_t * );
  58     /** A pointer to a deallocation function */
  59     void     ( * pf_free ) ( vlc_value_t * );
  60
  61     /** Creation count: we only destroy the variable if it reaches 0 */
  62     int          i_usage;
  63
  64     /** If the variable has min/max/step values */
  65     vlc_value_t  min, max, step;
  66
  67     /** Index of the default choice, if the variable is to be chosen in
  68      * a list */
  69     int          i_default;
  70     /** List of choices */
  71     vlc_list_t   choices;
  72     /** List of friendly names for the choices */
  73     vlc_list_t   choices_text;
  74
  75     /** Set to TRUE if the variable is in a callback */
  76     vlc_bool_t   b_incallback;
  77
  78     /** Number of registered callbacks */
  79     int                i_entries;
  80     /** Array of registered callbacks */
  81     callback_entry_t * p_entries;
  82 };
  83
  84 /*****************************************************************************
  85  * Variable types - probably very incomplete
  86  *****************************************************************************/
  87 #define VLC_VAR_TYPE      0x00ff
  88 #define VLC_VAR_FLAGS     0xff00
  89
  90 /** \defgroup var_flags Additive flags
  91  * These flags are added to the type field of the variable. Most as a result of
  92  * a __var_Change() call, but some may be added at creation time
  93  * @{
  94  */
  95 #define VLC_VAR_HASCHOICE 0x0100
  96 #define VLC_VAR_HASMIN    0x0200
  97 #define VLC_VAR_HASMAX    0x0400
  98 #define VLC_VAR_HASSTEP   0x0800
  99
 100 #define VLC_VAR_ISLIST    0x1000
 101 #define VLC_VAR_ISCOMMAND 0x2000
 102 #define VLC_VAR_ISCONFIG  0x2000
 103
 104 /** Creation flag */
 105 #define VLC_VAR_DOINHERIT 0x8000
 106 /**@}*/
 107
 108 /**
 109  * \defgroup var_action Variable actions
 110  * These are the different actions that can be used with __var_Change().
 111  * The parameters given are the meaning of the two last parameters of
 112  * __var_Change() when this action is being used.
 113  * @{
 114  */
 115
 116 /**
 117  * Set the minimum value of this variable
 118  * \param p_val The new minimum value
 119  * \param p_val2 Unused
 120  */
 121 #define VLC_VAR_SETMIN              0x0010
 122 /**
 123  * Set the maximum value of this variable
 124  * \param p_val The new maximum value
 125  * \param p_val2 Unused
 126  */
 127 #define VLC_VAR_SETMAX              0x0011
 128 #define VLC_VAR_SETSTEP             0x0012
 129
 130 /**
 131  * Set the value of this variable without triggering any callbacks
 132  * \param p_val The new value
 133  * \param p_val2 Unused
 134  */
 135 #define VLC_VAR_SETVALUE            0x0013
 136
 137 #define VLC_VAR_SETTEXT             0x0014
 138 #define VLC_VAR_GETTEXT             0x0015
 139
 140 #define VLC_VAR_ADDCHOICE           0x0020
 141 #define VLC_VAR_DELCHOICE           0x0021
 142 #define VLC_VAR_CLEARCHOICES        0x0022
 143 #define VLC_VAR_SETDEFAULT          0x0023
 144 #define VLC_VAR_GETCHOICES          0x0024
 145 #define VLC_VAR_FREECHOICES         0x0025
 146 #define VLC_VAR_GETLIST             0x0026
 147 #define VLC_VAR_FREELIST            0x0027
 148 #define VLC_VAR_CHOICESCOUNT        0x0028
 149
 150 #define VLC_VAR_INHERITVALUE        0x0030
 151 #define VLC_VAR_TRIGGER_CALLBACKS   0x0035
 152 /**@}*/
 153
 154 /*****************************************************************************
 155  * Prototypes
 156  *****************************************************************************/
 157 VLC_EXPORT( int, __var_Create, ( vlc_object_t *, const char *, int ) );
 158 VLC_EXPORT( int, __var_Destroy, ( vlc_object_t *, const char * ) );
 159
 160 VLC_EXPORT( int, __var_Change, ( vlc_object_t *, const char *, int, vlc_value_t *, vlc_value_t * ) );
 161
 162 VLC_EXPORT( int, __var_Type, ( vlc_object_t *, const char * ) );
 163 VLC_EXPORT( int, __var_Set, ( vlc_object_t *, const char *, vlc_value_t ) );
 164 VLC_EXPORT( int, __var_Get, ( vlc_object_t *, const char *, vlc_value_t * ) );
 165
 166 #define var_OptionParse(a,b) __var_OptionParse( VLC_OBJECT( a ) , b )
 167 VLC_EXPORT( void, __var_OptionParse, ( vlc_object_t *, const char * ) );
 168
 169 /**
 170  * __var_Create() with automatic casting.
 171  */
 172 #define var_Create(a,b,c) __var_Create( VLC_OBJECT(a), b, c )
 173 /**
 174  * __var_Destroy() with automatic casting
 175  */
 176 #define var_Destroy(a,b) __var_Destroy( VLC_OBJECT(a), b )
 177
 178 /**
 179  * __var_Change() with automatic casting
 180  */
 181 #define var_Change(a,b,c,d,e) __var_Change( VLC_OBJECT(a), b, c, d, e )
 182
 183 /**
 184  * __var_Type() with automatic casting
 185  */
 186 #define var_Type(a,b) __var_Type( VLC_OBJECT(a), b )
 187 /**
 188  * __var_Set() with automatic casting
 189  */
 190 #define var_Set(a,b,c) __var_Set( VLC_OBJECT(a), b, c )
 191 /**
 192  * __var_Get() with automatic casting
 193  */
 194 #define var_Get(a,b,c) __var_Get( VLC_OBJECT(a), b, c )
 195
 196 /*****************************************************************************
 197  * Variable callbacks
 198  *****************************************************************************
 199  * int MyCallback( vlc_object_t *p_this,
 200  *                 char const *psz_variable,
 201  *                 vlc_value_t oldvalue,
 202  *                 vlc_value_t newvalue,
 203  *                 void *p_data);
 204  *****************************************************************************/
 205 VLC_EXPORT( int, __var_AddCallback, ( vlc_object_t *, const char *, vlc_callback_t, void * ) );
 206 VLC_EXPORT( int, __var_DelCallback, ( vlc_object_t *, const char *, vlc_callback_t, void * ) );
 207
 208 /**
 209  * __var_AddCallback() with automatic casting
 210  */
 211 #define var_AddCallback(a,b,c,d) __var_AddCallback( VLC_OBJECT(a), b, c, d )
 212
 213 /**
 214  * __var_DelCallback() with automatic casting
 215  */
 216 #define var_DelCallback(a,b,c,d) __var_DelCallback( VLC_OBJECT(a), b, c, d )
 217
 218 /*****************************************************************************
 219  * helpers functions
 220  *****************************************************************************/
 221
 222 /**
 223  * Set the value of an integer variable
 224  *
 225  * \param p_obj The object that holds the variable
 226  * \param psz_name The name of the variable
 227  * \param i The new integer value of this variable
 228  */
 229 static inline int __var_SetInteger( vlc_object_t *p_obj, const char *psz_name, int i )
 230 {
 231     vlc_value_t val;
 232     val.i_int = i;
 233     return __var_Set( p_obj, psz_name, val );
 234 }
 235 #define var_SetInteger(a,b,c)   __var_SetInteger( VLC_OBJECT(a),b,c)
 236 /**
 237  * Set the value of an boolean variable
 238  *
 239  * \param p_obj The object that holds the variable
 240  * \param psz_name The name of the variable
 241  * \param b The new boolean value of this variable
 242  */
 243 static inline int __var_SetBool( vlc_object_t *p_obj, const char *psz_name, vlc_bool_t b )
 244 {
 245     vlc_value_t val;
 246     val.b_bool = b;
 247     return __var_Set( p_obj, psz_name, val );
 248 }
 249
 250 /**
 251  * Set the value of a time variable
 252  *
 253  * \param p_obj The object that holds the variable
 254  * \param psz_name The name of the variable
 255  * \param i The new time value of this variable
 256  */
 257 static inline int __var_SetTime( vlc_object_t *p_obj, const char *psz_name, int64_t i )
 258 {
 259     vlc_value_t val;
 260     val.i_time = i;
 261     return __var_Set( p_obj, psz_name, val );
 262 }
 263
 264 /**
 265  * Set the value of a float variable
 266  *
 267  * \param p_obj The object that holds the variable
 268  * \param psz_name The name of the variable
 269  * \param f The new float value of this variable
 270  */
 271 static inline int __var_SetFloat( vlc_object_t *p_obj, const char *psz_name, float f )
 272 {
 273     vlc_value_t val;
 274     val.f_float = f;
 275     return __var_Set( p_obj, psz_name, val );
 276 }
 277
 278 /**
 279  * Set the value of a string variable
 280  *
 281  * \param p_obj The object that holds the variable
 282  * \param psz_name The name of the variable
 283  * \param psz_string The new string value of this variable
 284  */
 285 static inline int __var_SetString( vlc_object_t *p_obj, const char *psz_name, char *psz_string )
 286 {
 287     vlc_value_t val;
 288     val.psz_string = psz_string;
 289     return __var_Set( p_obj, psz_name, val );
 290 }
 291
 292 /**
 293  * Trigger the callbacks on a void variable
 294  *
 295  * \param p_obj The object that holds the variable
 296  * \param psz_name The name of the variable
 297  */
 298 static inline int __var_SetVoid( vlc_object_t *p_obj, const char *psz_name )
 299 {
 300     vlc_value_t val;
 301     val.b_bool = VLC_TRUE;
 302     return __var_Set( p_obj, psz_name, val );
 303 }
 304 #define var_SetVoid(a,b)        __var_SetVoid( VLC_OBJECT(a),b)
 305
 306 /**
 307  * __var_SetBool() with automatic casting
 308  */
 309 #define var_SetBool(a,b,c)   __var_SetBool( VLC_OBJECT(a),b,c)
 310
 311 /**
 312  * __var_SetTime() with automatic casting
 313  */
 314 #define var_SetTime(a,b,c)      __var_SetTime( VLC_OBJECT(a),b,c)
 315 /**
 316  * __var_SetFloat() with automatic casting
 317  */
 318 #define var_SetFloat(a,b,c)     __var_SetFloat( VLC_OBJECT(a),b,c)
 319 /**
 320  * __var_SetString() with automatic casting
 321  */
 322 #define var_SetString(a,b,c)     __var_SetString( VLC_OBJECT(a),b,c)
 323
 324 /**
 325  * Get an integer value
 326 *
 327  * \param p_obj The object that holds the variable
 328  * \param psz_name The name of the variable
 329  */
 330 static inline int __var_GetInteger( vlc_object_t *p_obj, const char *psz_name )
 331 {
 332     vlc_value_t val;val.i_int = 0;
 333     if( !__var_Get( p_obj, psz_name, &val ) )
 334         return val.i_int;
 335     else
 336         return 0;
 337 }
 338
 339 /**
 340  * Get a boolean value
 341  *
 342  * \param p_obj The object that holds the variable
 343  * \param psz_name The name of the variable
 344  */
 345 static inline int __var_GetBool( vlc_object_t *p_obj, const char *psz_name )
 346 {
 347     vlc_value_t val; val.b_bool = VLC_FALSE;
 348     if( !__var_Get( p_obj, psz_name, &val ) )
 349         return val.b_bool;
 350     else
 351         return VLC_FALSE;
 352 }
 353
 354 /**
 355  * Get a time value
 356  *
 357  * \param p_obj The object that holds the variable
 358  * \param psz_name The name of the variable
 359  */
 360 static inline int64_t __var_GetTime( vlc_object_t *p_obj, const char *psz_name )
 361 {
 362     vlc_value_t val; val.i_time = 0L;
 363     if( !__var_Get( p_obj, psz_name, &val ) )
 364         return val.i_time;
 365     else
 366         return 0;
 367 }
 368
 369 /**
 370  * Get a float value
 371  *
 372  * \param p_obj The object that holds the variable
 373  * \param psz_name The name of the variable
 374  */
 375 static inline float __var_GetFloat( vlc_object_t *p_obj, const char *psz_name )
 376 {
 377     vlc_value_t val; val.f_float = 0.0;
 378     if( !__var_Get( p_obj, psz_name, &val ) )
 379         return val.f_float;
 380     else
 381         return 0.0;
 382 }
 383
 384 /**
 385  * Get a string value
 386  *
 387  * \param p_obj The object that holds the variable
 388  * \param psz_name The name of the variable
 389  */
 390 static inline char *__var_GetString( vlc_object_t *p_obj, const char *psz_name )
 391 {
 392     vlc_value_t val; val.psz_string = NULL;
 393     if( !__var_Get( p_obj, psz_name, &val ) )
 394         return val.psz_string;
 395     else
 396         return strdup( "" );
 397 }
 398
 399 /**
 400  * __var_GetInteger() with automatic casting
 401  */
 402 #define var_GetInteger(a,b)   __var_GetInteger( VLC_OBJECT(a),b)
 403 /**
 404  * __var_GetBool() with automatic casting
 405  */
 406 #define var_GetBool(a,b)   __var_GetBool( VLC_OBJECT(a),b)
 407 /**
 408  * __var_GetTime() with automatic casting
 409  */
 410 #define var_GetTime(a,b)   __var_GetTime( VLC_OBJECT(a),b)
 411 /**
 412  * __var_GetFloat() with automatic casting
 413  */
 414 #define var_GetFloat(a,b)   __var_GetFloat( VLC_OBJECT(a),b)
 415 /**
 416  * __var_GetString() with automatic casting
 417  */
 418 #define var_GetString(a,b)   __var_GetString( VLC_OBJECT(a),b)
 419
 420
 421
 422 /**
 423  * Increment an integer variable
 424  * \param p_obj the object that holds the variable
 425  * \param psz_name the name of the variable
 426  */
 427 static inline void __var_IncInteger( vlc_object_t *p_obj, const char *psz_name )
 428 {
 429     int i_val = __var_GetInteger( p_obj, psz_name );
 430     __var_SetInteger( p_obj, psz_name, ++i_val );
 431 }
 432 #define var_IncInteger(a,b) __var_IncInteger( VLC_OBJECT(a), b )
 433
 434 /**
 435  * Decrement an integer variable
 436  * \param p_obj the object that holds the variable
 437  * \param psz_name the name of the variable
 438  */
 439 static inline void __var_DecInteger( vlc_object_t *p_obj, const char *psz_name )
 440 {
 441     int i_val = __var_GetInteger( p_obj, psz_name );
 442     __var_SetInteger( p_obj, psz_name, --i_val );
 443 }
 444 #define var_DecInteger(a,b) __var_DecInteger( VLC_OBJECT(a), b )
 445
 446 /**
 447  * Create a integer variable with inherit and get its value.
 448  *
 449  * \param p_obj The object that holds the variable
 450  * \param psz_name The name of the variable
 451  */
 452 static inline int __var_CreateGetInteger( vlc_object_t *p_obj, const char *psz_name )
 453 {
 454     vlc_value_t val;
 455
 456     __var_Create( p_obj, psz_name, VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
 457     if( !__var_Get( p_obj, psz_name, &val ) )
 458         return val.i_int;
 459     else
 460         return 0;
 461 }
 462
 463 /**
 464  * Create a boolean variable with inherit and get its value.
 465  *
 466  * \param p_obj The object that holds the variable
 467  * \param psz_name The name of the variable
 468  */
 469 static inline int __var_CreateGetBool( vlc_object_t *p_obj, const char *psz_name )
 470 {
 471     vlc_value_t val;
 472
 473     __var_Create( p_obj, psz_name, VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
 474     if( !__var_Get( p_obj, psz_name, &val ) )
 475         return val.b_bool;
 476     else
 477         return VLC_FALSE;
 478 }
 479
 480 /**
 481  * Create a time variable with inherit and get its value.
 482  *
 483  * \param p_obj The object that holds the variable
 484  * \param psz_name The name of the variable
 485  */
 486 static inline int64_t __var_CreateGetTime( vlc_object_t *p_obj, const char *psz_name )
 487 {
 488     vlc_value_t val;
 489
 490     __var_Create( p_obj, psz_name, VLC_VAR_TIME | VLC_VAR_DOINHERIT );
 491     if( !__var_Get( p_obj, psz_name, &val ) )
 492         return val.i_time;
 493     else
 494         return 0;
 495 }
 496
 497 /**
 498  * Create a float variable with inherit and get its value.
 499  *
 500  * \param p_obj The object that holds the variable
 501  * \param psz_name The name of the variable
 502  */
 503 static inline float __var_CreateGetFloat( vlc_object_t *p_obj, const char *psz_name )
 504 {
 505     vlc_value_t val;
 506
 507     __var_Create( p_obj, psz_name, VLC_VAR_FLOAT | VLC_VAR_DOINHERIT );
 508     if( !__var_Get( p_obj, psz_name, &val ) )
 509         return val.f_float;
 510     else
 511         return 0.0;
 512 }
 513
 514 /**
 515  * Create a string variable with inherit and get its value.
 516  *
 517  * \param p_obj The object that holds the variable
 518  * \param psz_name The name of the variable
 519  */
 520 static inline char *__var_CreateGetString( vlc_object_t *p_obj, const char *psz_name )
 521 {
 522     vlc_value_t val;
 523
 524     __var_Create( p_obj, psz_name, VLC_VAR_STRING | VLC_VAR_DOINHERIT );
 525     if( !__var_Get( p_obj, psz_name, &val ) )
 526         return val.psz_string;
 527     else
 528         return strdup( "" );
 529 }
 530
 531 /**
 532  * __var_CreateGetInteger() with automatic casting
 533  */
 534 #define var_CreateGetInteger(a,b)   __var_CreateGetInteger( VLC_OBJECT(a),b)
 535 /**
 536  * __var_CreateGetBool() with automatic casting
 537  */
 538 #define var_CreateGetBool(a,b)   __var_CreateGetBool( VLC_OBJECT(a),b)
 539 /**
 540  * __var_CreateGetTime() with automatic casting
 541  */
 542 #define var_CreateGetTime(a,b)   __var_CreateGetTime( VLC_OBJECT(a),b)
 543 /**
 544  * __var_CreateGetFloat() with automatic casting
 545  */
 546 #define var_CreateGetFloat(a,b)   __var_CreateGetFloat( VLC_OBJECT(a),b)
 547 /**
 548  * __var_CreateGetString() with automatic casting
 549  */
 550 #define var_CreateGetString(a,b)   __var_CreateGetString( VLC_OBJECT(a),b)
 551
 552 /**
 553  * @}
 554  */
 555