include/variables.h

   1 /*****************************************************************************
   2  * variables.h: variables handling
   3  *****************************************************************************
   4  * Copyright (C) 2002-2004 VideoLAN
   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., 59 Temple Place - Suite 330, Boston, MA  02111, 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 /**
  91  * \defgroup var_type Variable types
  92  * These are the different types a vlc variable can have.
  93  * @{
  94  */
  95 #define VLC_VAR_VOID      0x0010
  96 #define VLC_VAR_BOOL      0x0020
  97 #define VLC_VAR_INTEGER   0x0030
  98 #define VLC_VAR_HOTKEY    0x0031
  99 #define VLC_VAR_STRING    0x0040
 100 #define VLC_VAR_MODULE    0x0041
 101 #define VLC_VAR_FILE      0x0042
 102 #define VLC_VAR_DIRECTORY 0x0043
 103 #define VLC_VAR_VARIABLE  0x0044
 104 #define VLC_VAR_FLOAT     0x0050
 105 #define VLC_VAR_TIME      0x0060
 106 #define VLC_VAR_ADDRESS   0x0070
 107 #define VLC_VAR_MUTEX     0x0080
 108 #define VLC_VAR_LIST      0x0090
 109 /**@}*/
 110 /** \defgroup var_flags Additive flags
 111  * These flags are added to the type field of the variable. Most as a result of
 112  * a __var_Change() call, but some may be added at creation time
 113  * @{
 114  */
 115 #define VLC_VAR_HASCHOICE 0x0100
 116 #define VLC_VAR_HASMIN    0x0200
 117 #define VLC_VAR_HASMAX    0x0400
 118 #define VLC_VAR_HASSTEP   0x0800
 119
 120 #define VLC_VAR_ISLIST    0x1000
 121 #define VLC_VAR_ISCOMMAND 0x2000
 122 #define VLC_VAR_ISCONFIG  0x2000
 123
 124 /** Creation flag */
 125 #define VLC_VAR_DOINHERIT 0x8000
 126 /**@}*/
 127
 128 /**
 129  * \defgroup var_action Variable actions
 130  * These are the different actions that can be used with __var_Change().
 131  * The parameters given are the meaning of the two last parameters of
 132  * __var_Change() when this action is being used.
 133  * @{
 134  */
 135
 136 /**
 137  * Set the minimum value of this variable
 138  * \param p_val The new minimum value
 139  * \param p_val2 Unused
 140  */
 141 #define VLC_VAR_SETMIN              0x0010
 142 /**
 143  * Set the maximum value of this variable
 144  * \param p_val The new maximum value
 145  * \param p_val2 Unused
 146  */
 147 #define VLC_VAR_SETMAX              0x0011
 148 #define VLC_VAR_SETSTEP             0x0012
 149
 150 /**
 151  * Set the value of this variable without triggering any callbacks
 152  * \param p_val The new value
 153  * \param p_val2 Unused
 154  */
 155 #define VLC_VAR_SETVALUE            0x0013
 156
 157 #define VLC_VAR_SETTEXT             0x0014
 158 #define VLC_VAR_GETTEXT             0x0015
 159
 160 #define VLC_VAR_ADDCHOICE           0x0020
 161 #define VLC_VAR_DELCHOICE           0x0021
 162 #define VLC_VAR_CLEARCHOICES        0x0022
 163 #define VLC_VAR_SETDEFAULT          0x0023
 164 #define VLC_VAR_GETCHOICES          0x0024
 165 #define VLC_VAR_FREECHOICES         0x0025
 166 #define VLC_VAR_GETLIST             0x0026
 167 #define VLC_VAR_FREELIST            0x0027
 168 #define VLC_VAR_CHOICESCOUNT        0x0028
 169
 170 #define VLC_VAR_INHERITVALUE        0x0030
 171 #define VLC_VAR_TRIGGER_CALLBACKS   0x0035
 172 /**@}*/
 173
 174 /*****************************************************************************
 175  * Prototypes
 176  *****************************************************************************/
 177 VLC_EXPORT( int, __var_Create, ( vlc_object_t *, const char *, int ) );
 178 VLC_EXPORT( int, __var_Destroy, ( vlc_object_t *, const char * ) );
 179
 180 VLC_EXPORT( int, __var_Change, ( vlc_object_t *, const char *, int, vlc_value_t *, vlc_value_t * ) );
 181
 182 VLC_EXPORT( int, __var_Type, ( vlc_object_t *, const char * ) );
 183 VLC_EXPORT( int, __var_Set, ( vlc_object_t *, const char *, vlc_value_t ) );
 184 VLC_EXPORT( int, __var_Get, ( vlc_object_t *, const char *, vlc_value_t * ) );
 185
 186 /**
 187  * __var_Create() with automatic casting.
 188  */
 189 #define var_Create(a,b,c) __var_Create( VLC_OBJECT(a), b, c )
 190 /**
 191  * __var_Destroy() with automatic casting
 192  */
 193 #define var_Destroy(a,b) __var_Destroy( VLC_OBJECT(a), b )
 194
 195 /**
 196  * __var_Change() with automatic casting
 197  */
 198 #define var_Change(a,b,c,d,e) __var_Change( VLC_OBJECT(a), b, c, d, e )
 199
 200 /**
 201  * __var_Type() with automatic casting
 202  */
 203 #define var_Type(a,b) __var_Type( VLC_OBJECT(a), b )
 204 /**
 205  * __var_Set() with automatic casting
 206  */
 207 #define var_Set(a,b,c) __var_Set( VLC_OBJECT(a), b, c )
 208 /**
 209  * __var_Get() with automatic casting
 210  */
 211 #define var_Get(a,b,c) __var_Get( VLC_OBJECT(a), b, c )
 212
 213 /*****************************************************************************
 214  * Variable callbacks
 215  *****************************************************************************
 216  * int MyCallback( vlc_object_t *p_this,
 217  *                 char const *psz_variable,
 218  *                 vlc_value_t oldvalue,
 219  *                 vlc_value_t newvalue,
 220  *                 void *p_data);
 221  *****************************************************************************/
 222 VLC_EXPORT( int, __var_AddCallback, ( vlc_object_t *, const char *, vlc_callback_t, void * ) );
 223 VLC_EXPORT( int, __var_DelCallback, ( vlc_object_t *, const char *, vlc_callback_t, void * ) );
 224
 225 /**
 226  * __var_AddCallback() with automatic casting
 227  */
 228 #define var_AddCallback(a,b,c,d) __var_AddCallback( VLC_OBJECT(a), b, c, d )
 229
 230 /**
 231  * __var_DelCallback() with automatic casting
 232  */
 233 #define var_DelCallback(a,b,c,d) __var_DelCallback( VLC_OBJECT(a), b, c, d )
 234
 235 /*****************************************************************************
 236  * helpers functions
 237  *****************************************************************************/
 238
 239 /**
 240  * Set the value of an integer variable
 241  *
 242  * \param p_obj The object that holds the variable
 243  * \param psz_name The name of the variable
 244  * \param i The new integer value of this variable
 245  */
 246 static inline int __var_SetInteger( vlc_object_t *p_obj, const char *psz_name, int i )
 247 {
 248     vlc_value_t val;
 249     val.i_int = i;
 250     return __var_Set( p_obj, psz_name, val );
 251 }
 252
 253 /**
 254  * Set the value of an boolean variable
 255  *
 256  * \param p_obj The object that holds the variable
 257  * \param psz_name The name of the variable
 258  * \param b The new boolean value of this variable
 259  */
 260 static inline int __var_SetBool( vlc_object_t *p_obj, const char *psz_name, vlc_bool_t b )
 261 {
 262     vlc_value_t val;
 263     val.b_bool = b;
 264     return __var_Set( p_obj, psz_name, val );
 265 }
 266
 267 /**
 268  * Set the value of a time variable
 269  *
 270  * \param p_obj The object that holds the variable
 271  * \param psz_name The name of the variable
 272  * \param i The new time value of this variable
 273  */
 274 static inline int __var_SetTime( vlc_object_t *p_obj, const char *psz_name, int64_t i )
 275 {
 276     vlc_value_t val;
 277     val.i_time = i;
 278     return __var_Set( p_obj, psz_name, val );
 279 }
 280
 281 /**
 282  * Set the value of a float variable
 283  *
 284  * \param p_obj The object that holds the variable
 285  * \param psz_name The name of the variable
 286  * \param f The new float value of this variable
 287  */
 288 static inline int __var_SetFloat( vlc_object_t *p_obj, const char *psz_name, float f )
 289 {
 290     vlc_value_t val;
 291     val.f_float = f;
 292     return __var_Set( p_obj, psz_name, val );
 293 }
 294
 295 /**
 296  * Set the value of a string variable
 297  *
 298  * \param p_obj The object that holds the variable
 299  * \param psz_name The name of the variable
 300  * \param psz_string The new string value of this variable
 301  */
 302 static inline int __var_SetString( vlc_object_t *p_obj, const char *psz_name, char *psz_string )
 303 {
 304     vlc_value_t val;
 305     val.psz_string = psz_string;
 306     return __var_Set( p_obj, psz_name, val );
 307 }
 308
 309 /**
 310  * Trigger the callbacks on a void variable
 311  *
 312  * \param p_obj The object that holds the variable
 313  * \param psz_name The name of the variable
 314  */
 315 static inline int __var_SetVoid( vlc_object_t *p_obj, const char *psz_name )
 316 {
 317     vlc_value_t val;
 318     val.b_bool = VLC_TRUE;
 319     return __var_Set( p_obj, psz_name, val );
 320 }
 321
 322 /**
 323  * __var_SetInteger() with automatic casting
 324  */
 325 #define var_SetInteger(a,b,c)   __var_SetInteger( VLC_OBJECT(a),b,c)
 326 /**
 327  * __var_SetBool() with automatic casting
 328  */
 329 #define var_SetBool(a,b,c)   __var_SetBool( VLC_OBJECT(a),b,c)
 330
 331 /**
 332  * __var_SetTime() with automatic casting
 333  */
 334 #define var_SetTime(a,b,c)      __var_SetTime( VLC_OBJECT(a),b,c)
 335 /**
 336  * __var_SetFloat() with automatic casting
 337  */
 338 #define var_SetFloat(a,b,c)     __var_SetFloat( VLC_OBJECT(a),b,c)
 339 /**
 340  * __var_SetString() with automatic casting
 341  */
 342 #define var_SetString(a,b,c)     __var_SetString( VLC_OBJECT(a),b,c)
 343 /**
 344  * __var_SetVoid() with automatic casting
 345  */
 346 #define var_SetVoid(a,b)        __var_SetVoid( VLC_OBJECT(a),b)
 347
 348 /**
 349  * Get a integer value
 350  *
 351  * \param p_obj The object that holds the variable
 352  * \param psz_name The name of the variable
 353  */
 354 static inline int __var_GetInteger( vlc_object_t *p_obj, const char *psz_name )
 355 {
 356     vlc_value_t val;
 357     if( !__var_Get( p_obj, psz_name, &val ) )
 358         return val.i_int;
 359     else
 360         return 0;
 361 }
 362
 363 /**
 364  * Get a boolean value
 365  *
 366  * \param p_obj The object that holds the variable
 367  * \param psz_name The name of the variable
 368  */
 369 static inline int __var_GetBool( vlc_object_t *p_obj, const char *psz_name )
 370 {
 371     vlc_value_t val;
 372     if( !__var_Get( p_obj, psz_name, &val ) )
 373         return val.b_bool;
 374     else
 375         return VLC_FALSE;
 376 }
 377
 378 /**
 379  * Get a time value
 380  *
 381  * \param p_obj The object that holds the variable
 382  * \param psz_name The name of the variable
 383  */
 384 static inline int64_t __var_GetTime( vlc_object_t *p_obj, const char *psz_name )
 385 {
 386     vlc_value_t val;
 387     if( !__var_Get( p_obj, psz_name, &val ) )
 388         return val.i_time;
 389     else
 390         return 0;
 391 }
 392
 393 /**
 394  * Get a float value
 395  *
 396  * \param p_obj The object that holds the variable
 397  * \param psz_name The name of the variable
 398  */
 399 static inline float __var_GetFloat( vlc_object_t *p_obj, const char *psz_name )
 400 {
 401     vlc_value_t val;
 402     if( !__var_Get( p_obj, psz_name, &val ) )
 403         return val.f_float;
 404     else
 405         return 0.0;
 406 }
 407
 408 /**
 409  * Get a string value
 410  *
 411  * \param p_obj The object that holds the variable
 412  * \param psz_name The name of the variable
 413  */
 414 static inline char *__var_GetString( vlc_object_t *p_obj, const char *psz_name )
 415 {
 416     vlc_value_t val;
 417     if( !__var_Get( p_obj, psz_name, &val ) )
 418         return val.psz_string;
 419     else
 420         return strdup( "" );
 421 }
 422
 423 /**
 424  * __var_GetInteger() with automatic casting
 425  */
 426 #define var_GetInteger(a,b)   __var_GetInteger( VLC_OBJECT(a),b)
 427 /**
 428  * __var_GetBool() with automatic casting
 429  */
 430 #define var_GetBool(a,b)   __var_GetBool( VLC_OBJECT(a),b)
 431 /**
 432  * __var_GetTime() with automatic casting
 433  */
 434 #define var_GetTime(a,b)   __var_GetTime( VLC_OBJECT(a),b)
 435 /**
 436  * __var_GetFloat() with automatic casting
 437  */
 438 #define var_GetFloat(a,b)   __var_GetFloat( VLC_OBJECT(a),b)
 439 /**
 440  * __var_GetString() with automatic casting
 441  */
 442 #define var_GetString(a,b)   __var_GetString( VLC_OBJECT(a),b)
 443
 444
 445 /**
 446  * Create a integer variable with inherit and get its value.
 447  *
 448  * \param p_obj The object that holds the variable
 449  * \param psz_name The name of the variable
 450  */
 451 static inline int __var_CreateGetInteger( vlc_object_t *p_obj, const char *psz_name )
 452 {
 453     vlc_value_t val;
 454
 455     __var_Create( p_obj, psz_name, VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
 456     if( !__var_Get( p_obj, psz_name, &val ) )
 457         return val.i_int;
 458     else
 459         return 0;
 460 }
 461
 462 /**
 463  * Create a boolean variable with inherit and get its value.
 464  *
 465  * \param p_obj The object that holds the variable
 466  * \param psz_name The name of the variable
 467  */
 468 static inline int __var_CreateGetBool( vlc_object_t *p_obj, const char *psz_name )
 469 {
 470     vlc_value_t val;
 471
 472     __var_Create( p_obj, psz_name, VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
 473     if( !__var_Get( p_obj, psz_name, &val ) )
 474         return val.b_bool;
 475     else
 476         return VLC_FALSE;
 477 }
 478
 479 /**
 480  * Create a time variable with inherit and get its value.
 481  *
 482  * \param p_obj The object that holds the variable
 483  * \param psz_name The name of the variable
 484  */
 485 static inline int64_t __var_CreateGetTime( vlc_object_t *p_obj, const char *psz_name )
 486 {
 487     vlc_value_t val;
 488
 489     __var_Create( p_obj, psz_name, VLC_VAR_TIME | VLC_VAR_DOINHERIT );
 490     if( !__var_Get( p_obj, psz_name, &val ) )
 491         return val.i_time;
 492     else
 493         return 0;
 494 }
 495
 496 /**
 497  * Create a float variable with inherit and get its value.
 498  *
 499  * \param p_obj The object that holds the variable
 500  * \param psz_name The name of the variable
 501  */
 502 static inline float __var_CreateGetFloat( vlc_object_t *p_obj, const char *psz_name )
 503 {
 504     vlc_value_t val;
 505
 506     __var_Create( p_obj, psz_name, VLC_VAR_FLOAT | VLC_VAR_DOINHERIT );
 507     if( !__var_Get( p_obj, psz_name, &val ) )
 508         return val.f_float;
 509     else
 510         return 0.0;
 511 }
 512
 513 /**
 514  * Create a string variable with inherit and get its value.
 515  *
 516  * \param p_obj The object that holds the variable
 517  * \param psz_name The name of the variable
 518  */
 519 static inline char *__var_CreateGetString( vlc_object_t *p_obj, const char *psz_name )
 520 {
 521     vlc_value_t val;
 522
 523     __var_Create( p_obj, psz_name, VLC_VAR_STRING | VLC_VAR_DOINHERIT );
 524     if( !__var_Get( p_obj, psz_name, &val ) )
 525         return val.psz_string;
 526     else
 527         return strdup( "" );
 528 }
 529
 530 /**
 531  * __var_CreateGetInteger() with automatic casting
 532  */
 533 #define var_CreateGetInteger(a,b)   __var_CreateGetInteger( VLC_OBJECT(a),b)
 534 /**
 535  * __var_CreateGetBool() with automatic casting
 536  */
 537 #define var_CreateGetBool(a,b)   __var_CreateGetBool( VLC_OBJECT(a),b)
 538 /**
 539  * __var_CreateGetTime() with automatic casting
 540  */
 541 #define var_CreateGetTime(a,b)   __var_CreateGetTime( VLC_OBJECT(a),b)
 542 /**
 543  * __var_CreateGetFloat() with automatic casting
 544  */
 545 #define var_CreateGetFloat(a,b)   __var_CreateGetFloat( VLC_OBJECT(a),b)
 546 /**
 547  * __var_CreateGetString() with automatic casting
 548  */
 549 #define var_CreateGetString(a,b)   __var_CreateGetString( VLC_OBJECT(a),b)
 550
 551 /**
 552  * @}
 553  */
 554