1 /*****************************************************************************
2 * variables.c: routines for object variables handling
3 *****************************************************************************
4 * Copyright (C) 2002-2009 the VideoLAN team
7 * Authors: Samuel Hocevar <sam@zoy.org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
31 #include <vlc_common.h>
32 #include "variables.h"
38 /*****************************************************************************
40 *****************************************************************************/
41 struct callback_entry_t
43 vlc_callback_t pf_callback;
47 /*****************************************************************************
48 * Local comparison functions, returns 0 if v == w, < 0 if v < w, > 0 if v > w
49 *****************************************************************************/
50 static int CmpBool( vlc_value_t v, vlc_value_t w ) { return v.b_bool ? w.b_bool ? 0 : 1 : w.b_bool ? -1 : 0; }
51 static int CmpInt( vlc_value_t v, vlc_value_t w ) { return v.i_int == w.i_int ? 0 : v.i_int > w.i_int ? 1 : -1; }
52 static int CmpTime( vlc_value_t v, vlc_value_t w )
54 return v.i_time == w.i_time ? 0 : v.i_time > w.i_time ? 1 : -1;
56 static int CmpString( vlc_value_t v, vlc_value_t w )
59 return !w.psz_string ? 0 : -1;
61 return !w.psz_string ? 1 : strcmp( v.psz_string, w.psz_string );
63 static int CmpFloat( vlc_value_t v, vlc_value_t w ) { return v.f_float == w.f_float ? 0 : v.f_float > w.f_float ? 1 : -1; }
64 static int CmpAddress( vlc_value_t v, vlc_value_t w ) { return v.p_address == w.p_address ? 0 : v.p_address > w.p_address ? 1 : -1; }
66 /*****************************************************************************
67 * Local duplication functions, and local deallocation functions
68 *****************************************************************************/
69 static void DupDummy( vlc_value_t *p_val ) { (void)p_val; /* unused */ }
70 static void DupString( vlc_value_t *p_val )
72 p_val->psz_string = strdup( p_val->psz_string ? p_val->psz_string : "" );
75 static void DupList( vlc_value_t *p_val )
78 vlc_list_t *p_list = malloc( sizeof(vlc_list_t) );
80 p_list->i_count = p_val->p_list->i_count;
81 if( p_val->p_list->i_count )
83 p_list->p_values = malloc( p_list->i_count * sizeof(vlc_value_t) );
84 p_list->pi_types = malloc( p_list->i_count * sizeof(int) );
88 p_list->p_values = NULL;
89 p_list->pi_types = NULL;
92 for( i = 0; i < p_list->i_count; i++ )
94 p_list->p_values[i] = p_val->p_list->p_values[i];
95 p_list->pi_types[i] = p_val->p_list->pi_types[i];
96 switch( p_val->p_list->pi_types[i] & VLC_VAR_CLASS )
100 DupString( &p_list->p_values[i] );
107 p_val->p_list = p_list;
110 static void FreeDummy( vlc_value_t *p_val ) { (void)p_val; /* unused */ }
111 static void FreeString( vlc_value_t *p_val ) { free( p_val->psz_string ); }
112 static void FreeMutex( vlc_value_t *p_val ) { vlc_mutex_destroy( (vlc_mutex_t*)p_val->p_address ); free( p_val->p_address ); }
114 static void FreeList( vlc_value_t *p_val )
117 for( i = 0; i < p_val->p_list->i_count; i++ )
119 switch( p_val->p_list->pi_types[i] & VLC_VAR_CLASS )
122 FreeString( &p_val->p_list->p_values[i] );
125 FreeMutex( &p_val->p_list->p_values[i] );
132 if( p_val->p_list->i_count )
134 free( p_val->p_list->p_values );
135 free( p_val->p_list->pi_types );
137 free( p_val->p_list );
140 static const struct variable_ops_t
141 void_ops = { NULL, DupDummy, FreeDummy, },
142 addr_ops = { CmpAddress, DupDummy, FreeDummy, },
143 bool_ops = { CmpBool, DupDummy, FreeDummy, },
144 float_ops = { CmpFloat, DupDummy, FreeDummy, },
145 int_ops = { CmpInt, DupDummy, FreeDummy, },
146 list_ops = { CmpAddress, DupList, FreeList, },
147 mutex_ops = { CmpAddress, DupDummy, FreeMutex, },
148 string_ops = { CmpString, DupString, FreeString, },
149 time_ops = { CmpTime, DupDummy, FreeDummy, };
151 /*****************************************************************************
153 *****************************************************************************/
154 static int GetUnused ( vlc_object_t *, const char * );
155 static uint32_t HashString ( const char * );
156 static int Insert ( variable_t *, int, const char * );
157 static int InsertInner ( variable_t *, int, uint32_t );
158 static int Lookup ( variable_t *, size_t, const char * );
160 static void CheckValue ( variable_t *, vlc_value_t * );
162 static int InheritValue( vlc_object_t *, const char *, vlc_value_t *,
164 static int TriggerCallback( vlc_object_t *, variable_t **, const char *,
168 * Initialize a vlc variable
170 * We hash the given string and insert it into the sorted list. The insertion
171 * may require slow memory copies, but think about what we gain in the log(n)
172 * lookup phase when setting/getting the variable value!
174 * \param p_this The object in which to create the variable
175 * \param psz_name The name of the variable
176 * \param i_type The variables type. Must be one of \ref var_type combined with
177 * zero or more \ref var_flags
179 int __var_Create( vlc_object_t *p_this, const char *psz_name, int i_type )
183 static vlc_list_t dummy_null_list = {0, NULL, NULL};
184 vlc_object_internals_t *p_priv = vlc_internals( p_this );
186 vlc_mutex_lock( &p_priv->var_lock );
188 /* FIXME: if the variable already exists, we don't duplicate it. But we
189 * duplicate the lookups. It's not that serious, but if anyone finds some
190 * time to rework Insert() so that only one lookup has to be done, feel
192 i_new = Lookup( p_priv->p_vars, p_priv->i_vars, psz_name );
196 /* If the types differ, variable creation failed. */
197 if( (i_type & VLC_VAR_TYPE) != (p_priv->p_vars[i_new].i_type & VLC_VAR_TYPE) )
199 msg_Err( p_this, "Variable '%s' (0x%04x) already exist but with a different type (0x%04x)",
200 psz_name, p_priv->p_vars[i_new].i_type, i_type );
201 vlc_mutex_unlock( &p_priv->var_lock );
205 p_priv->p_vars[i_new].i_usage++;
206 p_priv->p_vars[i_new].i_type |= ( i_type & VLC_VAR_ISCOMMAND );
207 p_priv->p_vars[i_new].i_type |= ( i_type & VLC_VAR_HASCHOICE );
208 vlc_mutex_unlock( &p_priv->var_lock );
212 i_new = Insert( p_priv->p_vars, p_priv->i_vars, psz_name );
214 if( (p_priv->i_vars & 15) == 15 )
216 p_priv->p_vars = realloc( p_priv->p_vars,
217 (p_priv->i_vars+17) * sizeof(variable_t) );
220 memmove( p_priv->p_vars + i_new + 1,
221 p_priv->p_vars + i_new,
222 (p_priv->i_vars - i_new) * sizeof(variable_t) );
226 p_var = &p_priv->p_vars[i_new];
227 memset( p_var, 0, sizeof(*p_var) );
229 p_var->i_hash = HashString( psz_name );
230 p_var->psz_name = strdup( psz_name );
231 p_var->psz_text = NULL;
233 p_var->i_type = i_type & ~VLC_VAR_DOINHERIT;
237 p_var->i_default = -1;
238 p_var->choices.i_count = 0;
239 p_var->choices.p_values = NULL;
240 p_var->choices_text.i_count = 0;
241 p_var->choices_text.p_values = NULL;
243 p_var->b_incallback = false;
244 p_var->i_entries = 0;
245 p_var->p_entries = NULL;
247 /* Always initialize the variable, even if it is a list variable; this
248 * will lead to errors if the variable is not initialized, but it will
249 * not cause crashes in the variable handling. */
250 switch( i_type & VLC_VAR_CLASS )
253 p_var->ops = &bool_ops;
254 p_var->val.b_bool = false;
256 case VLC_VAR_INTEGER:
257 p_var->ops = &int_ops;
258 p_var->val.i_int = 0;
261 p_var->ops = &string_ops;
262 p_var->val.psz_string = NULL;
265 p_var->ops = &float_ops;
266 p_var->val.f_float = 0.0;
269 p_var->ops = &time_ops;
270 p_var->val.i_time = 0;
272 case VLC_VAR_ADDRESS:
273 p_var->ops = &addr_ops;
274 p_var->val.p_address = NULL;
277 p_var->ops = &mutex_ops;
278 p_var->val.p_address = malloc( sizeof(vlc_mutex_t) );
279 vlc_mutex_init( (vlc_mutex_t*)p_var->val.p_address );
282 p_var->ops = &list_ops;
283 p_var->val.p_list = &dummy_null_list;
286 p_var->ops = &void_ops;
290 /* Duplicate the default data we stored. */
291 p_var->ops->pf_dup( &p_var->val );
293 if( i_type & VLC_VAR_DOINHERIT )
297 if( InheritValue( p_this, psz_name, &val, p_var->i_type )
300 /* Free data if needed */
301 p_var->ops->pf_free( &p_var->val );
302 /* Set the variable */
305 if( i_type & VLC_VAR_HASCHOICE )
307 /* We must add the inherited value to our choice list */
308 p_var->i_default = 0;
310 INSERT_ELEM( p_var->choices.p_values, p_var->choices.i_count,
312 INSERT_ELEM( p_var->choices_text.p_values,
313 p_var->choices_text.i_count, 0, val );
314 p_var->ops->pf_dup( &p_var->choices.p_values[0] );
315 p_var->choices_text.p_values[0].psz_string = NULL;
320 vlc_mutex_unlock( &p_priv->var_lock );
326 * Destroy a vlc variable
328 * Look for the variable and destroy it if it is found. As in var_Create we
329 * do a call to memmove() but we have performance counterparts elsewhere.
331 * \param p_this The object that holds the variable
332 * \param psz_name The name of the variable
334 int __var_Destroy( vlc_object_t *p_this, const char *psz_name )
338 vlc_object_internals_t *p_priv = vlc_internals( p_this );
340 vlc_mutex_lock( &p_priv->var_lock );
342 i_var = GetUnused( p_this, psz_name );
345 vlc_mutex_unlock( &p_priv->var_lock );
349 p_var = &p_priv->p_vars[i_var];
351 if( p_var->i_usage > 1 )
354 vlc_mutex_unlock( &p_priv->var_lock );
358 /* Free value if needed */
359 p_var->ops->pf_free( &p_var->val );
361 /* Free choice list if needed */
362 if( p_var->choices.i_count )
364 for( i = 0 ; i < p_var->choices.i_count ; i++ )
366 p_var->ops->pf_free( &p_var->choices.p_values[i] );
367 free( p_var->choices_text.p_values[i].psz_string );
369 free( p_var->choices.p_values );
370 free( p_var->choices_text.p_values );
373 /* Free callbacks if needed */
374 if( p_var->p_entries )
376 free( p_var->p_entries );
379 free( p_var->psz_name );
380 free( p_var->psz_text );
382 memmove( p_priv->p_vars + i_var,
383 p_priv->p_vars + i_var + 1,
384 (p_priv->i_vars - i_var - 1) * sizeof(variable_t) );
386 if( (p_priv->i_vars & 15) == 0 )
388 p_priv->p_vars = realloc( p_priv->p_vars,
389 (p_priv->i_vars) * sizeof( variable_t ) );
394 vlc_mutex_unlock( &p_priv->var_lock );
400 * Perform an action on a variable
402 * \param p_this The object that holds the variable
403 * \param psz_name The name of the variable
404 * \param i_action The action to perform. Must be one of \ref var_action
405 * \param p_val First action parameter
406 * \param p_val2 Second action parameter
408 int __var_Change( vlc_object_t *p_this, const char *psz_name,
409 int i_action, vlc_value_t *p_val, vlc_value_t *p_val2 )
414 vlc_object_internals_t *p_priv = vlc_internals( p_this );
416 vlc_mutex_lock( &p_priv->var_lock );
418 i_var = Lookup( p_priv->p_vars, p_priv->i_vars, psz_name );
422 vlc_mutex_unlock( &p_priv->var_lock );
426 p_var = &p_priv->p_vars[i_var];
431 if( p_var->i_type & VLC_VAR_HASMIN )
433 p_var->ops->pf_free( &p_var->min );
435 p_var->i_type |= VLC_VAR_HASMIN;
437 p_var->ops->pf_dup( &p_var->min );
438 CheckValue( p_var, &p_var->val );
441 if( p_var->i_type & VLC_VAR_HASMIN )
447 if( p_var->i_type & VLC_VAR_HASMAX )
449 p_var->ops->pf_free( &p_var->max );
451 p_var->i_type |= VLC_VAR_HASMAX;
453 p_var->ops->pf_dup( &p_var->max );
454 CheckValue( p_var, &p_var->val );
457 if( p_var->i_type & VLC_VAR_HASMAX )
462 case VLC_VAR_SETSTEP:
463 if( p_var->i_type & VLC_VAR_HASSTEP )
465 p_var->ops->pf_free( &p_var->step );
467 p_var->i_type |= VLC_VAR_HASSTEP;
468 p_var->step = *p_val;
469 p_var->ops->pf_dup( &p_var->step );
470 CheckValue( p_var, &p_var->val );
472 case VLC_VAR_GETSTEP:
473 if( p_var->i_type & VLC_VAR_HASSTEP )
475 *p_val = p_var->step;
478 case VLC_VAR_ADDCHOICE:
479 i = p_var->choices.i_count;
481 INSERT_ELEM( p_var->choices.p_values, p_var->choices.i_count,
483 INSERT_ELEM( p_var->choices_text.p_values,
484 p_var->choices_text.i_count, i, *p_val );
485 p_var->ops->pf_dup( &p_var->choices.p_values[i] );
486 p_var->choices_text.p_values[i].psz_string =
487 ( p_val2 && p_val2->psz_string ) ?
488 strdup( p_val2->psz_string ) : NULL;
490 CheckValue( p_var, &p_var->val );
492 case VLC_VAR_DELCHOICE:
493 for( i = 0 ; i < p_var->choices.i_count ; i++ )
495 if( p_var->ops->pf_cmp( p_var->choices.p_values[i], *p_val ) == 0 )
501 if( i == p_var->choices.i_count )
504 vlc_mutex_unlock( &p_priv->var_lock );
508 if( p_var->i_default > i )
512 else if( p_var->i_default == i )
514 p_var->i_default = -1;
517 p_var->ops->pf_free( &p_var->choices.p_values[i] );
518 free( p_var->choices_text.p_values[i].psz_string );
519 REMOVE_ELEM( p_var->choices.p_values, p_var->choices.i_count, i );
520 REMOVE_ELEM( p_var->choices_text.p_values,
521 p_var->choices_text.i_count, i );
523 CheckValue( p_var, &p_var->val );
525 case VLC_VAR_CHOICESCOUNT:
526 p_val->i_int = p_var->choices.i_count;
528 case VLC_VAR_CLEARCHOICES:
529 for( i = 0 ; i < p_var->choices.i_count ; i++ )
531 p_var->ops->pf_free( &p_var->choices.p_values[i] );
533 for( i = 0 ; i < p_var->choices_text.i_count ; i++ )
534 free( p_var->choices_text.p_values[i].psz_string );
536 if( p_var->choices.i_count ) free( p_var->choices.p_values );
537 if( p_var->choices_text.i_count ) free( p_var->choices_text.p_values );
539 p_var->choices.i_count = 0;
540 p_var->choices.p_values = NULL;
541 p_var->choices_text.i_count = 0;
542 p_var->choices_text.p_values = NULL;
543 p_var->i_default = -1;
545 case VLC_VAR_SETDEFAULT:
546 /* FIXME: the list is sorted, dude. Use something cleverer. */
547 for( i = 0 ; i < p_var->choices.i_count ; i++ )
549 if( p_var->ops->pf_cmp( p_var->choices.p_values[i], *p_val ) == 0 )
555 if( i == p_var->choices.i_count )
561 p_var->i_default = i;
562 CheckValue( p_var, &p_var->val );
564 case VLC_VAR_SETVALUE:
565 /* Duplicate data if needed */
566 p_var->ops->pf_dup( p_val );
567 /* Backup needed stuff */
569 /* Check boundaries and list */
570 CheckValue( p_var, p_val );
571 /* Set the variable */
573 /* Free data if needed */
574 p_var->ops->pf_free( &oldval );
576 case VLC_VAR_GETCHOICES:
577 case VLC_VAR_GETLIST:
578 p_val->p_list = malloc( sizeof(vlc_list_t) );
579 if( p_val2 ) p_val2->p_list = malloc( sizeof(vlc_list_t) );
580 if( p_var->choices.i_count )
582 p_val->p_list->p_values = malloc( p_var->choices.i_count
583 * sizeof(vlc_value_t) );
584 p_val->p_list->pi_types = malloc( p_var->choices.i_count
588 p_val2->p_list->p_values =
589 malloc( p_var->choices.i_count * sizeof(vlc_value_t) );
590 p_val2->p_list->pi_types =
591 malloc( p_var->choices.i_count * sizeof(int) );
594 p_val->p_list->i_count = p_var->choices.i_count;
595 if( p_val2 ) p_val2->p_list->i_count = p_var->choices.i_count;
596 for( i = 0 ; i < p_var->choices.i_count ; i++ )
598 p_val->p_list->p_values[i] = p_var->choices.p_values[i];
599 p_val->p_list->pi_types[i] = p_var->i_type;
600 p_var->ops->pf_dup( &p_val->p_list->p_values[i] );
603 p_val2->p_list->p_values[i].psz_string =
604 p_var->choices_text.p_values[i].psz_string ?
605 strdup(p_var->choices_text.p_values[i].psz_string) : NULL;
606 p_val2->p_list->pi_types[i] = VLC_VAR_STRING;
610 case VLC_VAR_SETTEXT:
611 free( p_var->psz_text );
612 if( p_val && p_val->psz_string )
613 p_var->psz_text = strdup( p_val->psz_string );
615 p_var->psz_text = NULL;
617 case VLC_VAR_GETTEXT:
618 p_val->psz_string = NULL;
619 if( p_var->psz_text )
621 p_val->psz_string = strdup( p_var->psz_text );
624 case VLC_VAR_INHERITVALUE:
628 if( InheritValue( p_this,
629 p_val2 ? p_val2->psz_string : psz_name,
630 &val, p_var->i_type )
633 /* Duplicate already done */
635 /* Backup needed stuff */
637 /* Check boundaries and list */
638 CheckValue( p_var, &val );
639 /* Set the variable */
641 /* Free data if needed */
642 p_var->ops->pf_free( &oldval );
648 p_var->ops->pf_dup( p_val );
653 case VLC_VAR_SETISCOMMAND:
654 p_var->i_type |= VLC_VAR_ISCOMMAND;
661 vlc_mutex_unlock( &p_priv->var_lock );
668 * Perform a Get and Set on a variable
670 * \param p_this: The object that hold the variable
671 * \param psz_name: the name of the variable
672 * \param i_action: the action to perform
673 * \param p_val: The action parameter
674 * \return vlc error codes
676 int __var_GetAndSet( vlc_object_t *p_this, const char *psz_name, int i_action,
680 int i_ret = VLC_SUCCESS;
683 vlc_object_internals_t *p_priv = vlc_internals( p_this );
685 vlc_mutex_lock( &p_priv->var_lock );
686 i_var = GetUnused( p_this, psz_name );
689 vlc_mutex_unlock( &p_priv->var_lock );
693 p_var = &p_priv->p_vars[i_var];
695 /* Duplicated data if needed */
696 //p_var->ops->pf_dup( &val );
698 /* Backup needed stuff */
701 /* depending of the action requiered */
704 case VLC_VAR_TOGGLE_BOOL:
705 assert( ( p_var->i_type & VLC_VAR_BOOL ) == VLC_VAR_BOOL );
706 p_var->val.b_bool = !p_var->val.b_bool;
708 case VLC_VAR_INTEGER_INCDEC:
709 assert( ( p_var->i_type & VLC_VAR_INTEGER ) == VLC_VAR_INTEGER );
710 p_var->val.i_int += val.i_int;
713 vlc_mutex_unlock( &p_priv->var_lock );
717 /* Check boundaries */
718 CheckValue( p_var, &p_var->val );
720 /* Deal with callbacks.*/
721 if( p_var->i_entries )
722 i_ret = TriggerCallback( p_this, &p_var, psz_name, oldval );
724 vlc_mutex_unlock( &p_priv->var_lock );
731 * Request a variable's type
733 * \return The variable type if it exists, or 0 if the
734 * variable could not be found.
737 int __var_Type( vlc_object_t *p_this, const char *psz_name )
740 vlc_object_internals_t *p_priv = vlc_internals( p_this );
742 vlc_mutex_lock( &p_priv->var_lock );
744 i_var = Lookup( p_priv->p_vars, p_priv->i_vars, psz_name );
748 vlc_mutex_unlock( &p_priv->var_lock );
752 i_type = p_priv->p_vars[i_var].i_type;
754 vlc_mutex_unlock( &p_priv->var_lock );
759 int var_SetChecked( vlc_object_t *p_this, const char *psz_name,
760 int expected_type, vlc_value_t val )
763 int i_ret = VLC_SUCCESS;
766 vlc_object_internals_t *p_priv = vlc_internals( p_this );
768 vlc_mutex_lock( &p_priv->var_lock );
770 i_var = GetUnused( p_this, psz_name );
773 vlc_mutex_unlock( &p_priv->var_lock );
777 p_var = &p_priv->p_vars[i_var];
778 assert( expected_type == 0 ||
779 (p_var->i_type & VLC_VAR_CLASS) == expected_type );
781 /* Duplicate data if needed */
782 p_var->ops->pf_dup( &val );
784 /* Backup needed stuff */
787 /* Check boundaries and list */
788 CheckValue( p_var, &val );
790 /* Set the variable */
793 /* Deal with callbacks */
794 if( p_var->i_entries )
795 i_ret = TriggerCallback( p_this, &p_var, psz_name, oldval );
797 /* Free data if needed */
798 p_var->ops->pf_free( &oldval );
800 vlc_mutex_unlock( &p_priv->var_lock );
807 * Set a variable's value
809 * \param p_this The object that hold the variable
810 * \param psz_name The name of the variable
811 * \param val the value to set
813 int __var_Set( vlc_object_t *p_this, const char *psz_name, vlc_value_t val )
815 return var_SetChecked( p_this, psz_name, 0, val );
818 int var_GetChecked( vlc_object_t *p_this, const char *psz_name,
819 int expected_type, vlc_value_t *p_val )
821 vlc_object_internals_t *p_priv = vlc_internals( p_this );
822 int i_var, err = VLC_SUCCESS;
824 vlc_mutex_lock( &p_priv->var_lock );
826 i_var = Lookup( p_priv->p_vars, p_priv->i_vars, psz_name );
829 variable_t *p_var = &p_priv->p_vars[i_var];
831 assert( expected_type == 0 ||
832 (p_var->i_type & VLC_VAR_CLASS) == expected_type );
834 /* Really get the variable */
838 /* Alert if the type is VLC_VAR_VOID */
839 if( ( p_var->i_type & VLC_VAR_TYPE ) == VLC_VAR_VOID )
840 msg_Warn( p_this, "Calling var_GetVoid on the void variable '%s' (0x%04x)", psz_name, p_var->i_type );
843 /* Duplicate value if needed */
844 p_var->ops->pf_dup( p_val );
849 vlc_mutex_unlock( &p_priv->var_lock );
854 * Get a variable's value
856 * \param p_this The object that holds the variable
857 * \param psz_name The name of the variable
858 * \param p_val Pointer to a vlc_value_t that will hold the variable's value
859 * after the function is finished
861 int __var_Get( vlc_object_t *p_this, const char *psz_name, vlc_value_t *p_val )
863 return var_GetChecked( p_this, psz_name, 0, p_val );
867 * Register a callback in a variable
869 * We store a function pointer that will be called upon variable
872 * \param p_this The object that holds the variable
873 * \param psz_name The name of the variable
874 * \param pf_callback The function pointer
875 * \param p_data A generic pointer that will be passed as the last
876 * argument to the callback function.
878 * \warning The callback function is run in the thread that calls var_Set on
879 * the variable. Use proper locking. This thread may not have much
880 * time to spare, so keep callback functions short.
882 int __var_AddCallback( vlc_object_t *p_this, const char *psz_name,
883 vlc_callback_t pf_callback, void *p_data )
887 callback_entry_t entry;
888 vlc_object_internals_t *p_priv = vlc_internals( p_this );
890 entry.pf_callback = pf_callback;
891 entry.p_data = p_data;
893 vlc_mutex_lock( &p_priv->var_lock );
895 i_var = GetUnused( p_this, psz_name );
898 vlc_mutex_unlock( &p_priv->var_lock );
902 p_var = &p_priv->p_vars[i_var];
904 INSERT_ELEM( p_var->p_entries,
909 vlc_mutex_unlock( &p_priv->var_lock );
915 * Remove a callback from a variable
917 * pf_callback and p_data have to be given again, because different objects
918 * might have registered the same callback function.
920 int __var_DelCallback( vlc_object_t *p_this, const char *psz_name,
921 vlc_callback_t pf_callback, void *p_data )
925 vlc_object_internals_t *p_priv = vlc_internals( p_this );
927 vlc_mutex_lock( &p_priv->var_lock );
929 i_var = GetUnused( p_this, psz_name );
932 vlc_mutex_unlock( &p_priv->var_lock );
936 p_var = &p_priv->p_vars[i_var];
938 for( i_entry = p_var->i_entries ; i_entry-- ; )
940 if( p_var->p_entries[i_entry].pf_callback == pf_callback
941 && p_var->p_entries[i_entry].p_data == p_data )
946 else if( p_var->p_entries[i_entry].pf_callback == pf_callback )
948 msg_Warn( p_this, "Calling var_DelCallback for '%s' with the same "
949 "function but not the same data.", psz_name );
956 vlc_mutex_unlock( &p_priv->var_lock );
960 REMOVE_ELEM( p_var->p_entries, p_var->i_entries, i_entry );
962 vlc_mutex_unlock( &p_priv->var_lock );
968 * Trigger callback on a variable
970 * \param p_this The object that hold the variable
971 * \param psz_name The name of the variable
973 int __var_TriggerCallback( vlc_object_t *p_this, const char *psz_name )
976 int i_ret = VLC_SUCCESS;
978 vlc_object_internals_t *p_priv = vlc_internals( p_this );
980 vlc_mutex_lock( &p_priv->var_lock );
982 i_var = GetUnused( p_this, psz_name );
985 vlc_mutex_unlock( &p_priv->var_lock );
989 p_var = &p_priv->p_vars[i_var];
991 /* Deal with callbacks. Tell we're in a callback, release the lock,
992 * call stored functions, retake the lock. */
993 if( p_var->i_entries )
994 i_ret = TriggerCallback( p_this, &p_var, psz_name, p_var->val );
996 vlc_mutex_unlock( &p_priv->var_lock );
1000 /** Parse a stringified option
1001 * This function parse a string option and create the associated object
1003 * The option must be of the form "[no[-]]foo[=bar]" where foo is the
1004 * option name and bar is the value of the option.
1005 * \param p_obj the object in which the variable must be created
1006 * \param psz_option the option to parse
1007 * \param trusted whether the option is set by a trusted input or not
1010 void var_OptionParse( vlc_object_t *p_obj, const char *psz_option,
1013 char *psz_name, *psz_value;
1015 bool b_isno = false;
1018 val.psz_string = NULL;
1020 /* It's too much of a hassle to remove the ':' when we parse
1021 * the cmd line :) */
1022 if( psz_option[0] == ':' )
1025 if( !psz_option[0] )
1028 psz_name = strdup( psz_option );
1029 if( psz_name == NULL )
1032 psz_value = strchr( psz_name, '=' );
1033 if( psz_value != NULL )
1034 *psz_value++ = '\0';
1036 /* FIXME: :programs should be handled generically */
1037 if( !strcmp( psz_name, "programs" ) )
1038 i_type = VLC_VAR_LIST;
1040 i_type = config_GetType( p_obj, psz_name );
1042 if( !i_type && !psz_value )
1044 /* check for "no-foo" or "nofoo" */
1045 if( !strncmp( psz_name, "no-", 3 ) )
1047 memmove( psz_name, psz_name + 3, strlen(psz_name) + 1 - 3 );
1049 else if( !strncmp( psz_name, "no", 2 ) )
1051 memmove( psz_name, psz_name + 2, strlen(psz_name) + 1 - 2 );
1053 else goto cleanup; /* Option doesn't exist */
1056 i_type = config_GetType( p_obj, psz_name );
1058 if( !i_type ) goto cleanup; /* Option doesn't exist */
1060 if( ( i_type != VLC_VAR_BOOL ) &&
1061 ( !psz_value || !*psz_value ) ) goto cleanup; /* Invalid value */
1063 /* check if option is unsafe */
1066 module_config_t *p_config = config_FindConfig( p_obj, psz_name );
1067 if( !p_config || !p_config->b_safe )
1069 msg_Err( p_obj, "unsafe option \"%s\" has been ignored for "
1070 "security reasons", psz_name );
1076 /* Create the variable in the input object.
1077 * Children of the input object will be able to retreive this value
1078 * thanks to the inheritance property of the object variables. */
1079 __var_Create( p_obj, psz_name, i_type );
1084 val.b_bool = !b_isno;
1087 case VLC_VAR_INTEGER:
1088 val.i_int = strtol( psz_value, NULL, 0 );
1092 val.f_float = atof( psz_value );
1095 case VLC_VAR_STRING:
1096 case VLC_VAR_MODULE:
1098 case VLC_VAR_DIRECTORY:
1099 val.psz_string = psz_value;
1104 char *psz_orig, *psz_var;
1105 vlc_list_t *p_list = malloc(sizeof(vlc_list_t));
1106 val.p_list = p_list;
1107 p_list->i_count = 0;
1109 psz_var = psz_orig = strdup(psz_value);
1110 while( psz_var && *psz_var )
1112 char *psz_item = psz_var;
1114 while( *psz_var && *psz_var != ',' ) psz_var++;
1115 if( *psz_var == ',' )
1120 val2.i_int = strtol( psz_item, NULL, 0 );
1121 INSERT_ELEM( p_list->p_values, p_list->i_count,
1122 p_list->i_count, val2 );
1123 /* p_list->i_count is incremented twice by INSERT_ELEM */
1125 INSERT_ELEM( p_list->pi_types, p_list->i_count,
1126 p_list->i_count, VLC_VAR_INTEGER );
1136 __var_Set( p_obj, psz_name, val );
1138 /* If that's a list, remove all elements allocated */
1139 if( i_type == VLC_VAR_LIST )
1147 /* Following functions are local */
1149 /*****************************************************************************
1150 * GetUnused: find an unused (not in callback) variable from its name
1151 *****************************************************************************
1152 * We do i_tries tries before giving up, just in case the variable is being
1153 * modified and called from a callback.
1154 *****************************************************************************/
1155 static int GetUnused( vlc_object_t *p_this, const char *psz_name )
1157 vlc_object_internals_t *p_priv = vlc_internals( p_this );
1163 i_var = Lookup( p_priv->p_vars, p_priv->i_vars, psz_name );
1169 if( ! p_priv->p_vars[i_var].b_incallback )
1174 mutex_cleanup_push( &p_priv->var_lock );
1175 vlc_cond_wait( &p_priv->var_wait, &p_priv->var_lock );
1180 /*****************************************************************************
1181 * HashString: our cool hash function
1182 *****************************************************************************
1183 * This function is not intended to be crypto-secure, we only want it to be
1184 * fast and not suck too much. This one is pretty fast and did 0 collisions
1185 * in wenglish's dictionary.
1186 *****************************************************************************/
1187 static uint32_t HashString( const char *psz_string )
1189 uint32_t i_hash = 0;
1191 while( *psz_string )
1193 i_hash += *psz_string++;
1194 i_hash += i_hash << 10;
1195 i_hash ^= i_hash >> 8;
1201 /*****************************************************************************
1202 * Insert: find an empty slot to insert a new variable
1203 *****************************************************************************
1204 * We use a recursive inner function indexed on the hash. This function does
1205 * nothing in the rare cases where a collision may occur, see Lookup()
1206 * to see how we handle them.
1207 * XXX: does this really need to be written recursively?
1208 *****************************************************************************/
1209 static int Insert( variable_t *p_vars, int i_count, const char *psz_name )
1216 return InsertInner( p_vars, i_count, HashString( psz_name ) );
1219 static int InsertInner( variable_t *p_vars, int i_count, uint32_t i_hash )
1223 if( i_hash <= p_vars[0].i_hash )
1228 if( i_hash >= p_vars[i_count - 1].i_hash )
1233 i_middle = i_count / 2;
1235 /* We know that 0 < i_middle */
1236 if( i_hash < p_vars[i_middle].i_hash )
1238 return InsertInner( p_vars, i_middle, i_hash );
1241 /* We know that i_middle + 1 < i_count */
1242 if( i_hash > p_vars[i_middle + 1].i_hash )
1244 return i_middle + 1 + InsertInner( p_vars + i_middle + 1,
1245 i_count - i_middle - 1,
1249 return i_middle + 1;
1252 static int u32cmp( const void *key, const void *data )
1254 const variable_t *p_var = data;
1255 uint32_t hash = *(const uint32_t *)key ;
1257 if( hash > p_var->i_hash )
1259 if( hash < p_var->i_hash )
1264 /*****************************************************************************
1265 * Lookup: find an existing variable given its name
1266 *****************************************************************************
1267 * We use a recursive inner function indexed on the hash. Care is taken of
1268 * possible hash collisions.
1269 *****************************************************************************/
1270 static int Lookup( variable_t *p_vars, size_t i_count, const char *psz_name )
1275 i_hash = HashString( psz_name );
1276 p_var = bsearch( &i_hash, p_vars, i_count, sizeof( *p_var ), u32cmp );
1278 /* Hash not found */
1282 assert( i_count > 0 );
1284 /* Find the first entry with the right hash */
1285 while( (p_var > p_vars) && (i_hash == p_var[-1].i_hash) )
1288 assert( p_var->i_hash == i_hash );
1290 /* Hash collision should be very unlikely, but we cannot guarantee
1291 * it will never happen. So we do an exhaustive search amongst all
1292 * entries with the same hash. Typically, there is only one anyway. */
1293 for( variable_t *p_end = p_vars + i_count;
1294 (p_var < p_end) && (i_hash == p_var->i_hash);
1297 if( !strcmp( psz_name, p_var->psz_name ) )
1298 return p_var - p_vars;
1301 /* Hash found, but entry not found */
1305 /*****************************************************************************
1306 * CheckValue: check that a value is valid wrt. a variable
1307 *****************************************************************************
1308 * This function checks p_val's value against p_var's limitations such as
1309 * minimal and maximal value, step, in-list position, and modifies p_val if
1311 ****************************************************************************/
1312 static void CheckValue ( variable_t *p_var, vlc_value_t *p_val )
1314 /* Check that our variable is in the list */
1315 if( p_var->i_type & VLC_VAR_HASCHOICE && p_var->choices.i_count )
1319 /* This list is not sorted so go throug it (this is a small list) */
1320 for( i = p_var->choices.i_count ; i-- ; )
1322 if( p_var->ops->pf_cmp( *p_val, p_var->choices.p_values[i] ) == 0 )
1328 /* If not found, change it to anything vaguely valid */
1331 /* Free the old variable, get the new one, dup it */
1332 p_var->ops->pf_free( p_val );
1333 *p_val = p_var->choices.p_values[p_var->i_default >= 0
1334 ? p_var->i_default : 0 ];
1335 p_var->ops->pf_dup( p_val );
1339 /* Check that our variable is within the bounds */
1340 switch( p_var->i_type & VLC_VAR_TYPE )
1342 case VLC_VAR_INTEGER:
1343 if( p_var->i_type & VLC_VAR_HASSTEP && p_var->step.i_int
1344 && (p_val->i_int % p_var->step.i_int) )
1346 p_val->i_int = (p_val->i_int + (p_var->step.i_int / 2))
1347 / p_var->step.i_int * p_var->step.i_int;
1349 if( p_var->i_type & VLC_VAR_HASMIN
1350 && p_val->i_int < p_var->min.i_int )
1352 p_val->i_int = p_var->min.i_int;
1354 if( p_var->i_type & VLC_VAR_HASMAX
1355 && p_val->i_int > p_var->max.i_int )
1357 p_val->i_int = p_var->max.i_int;
1361 if( p_var->i_type & VLC_VAR_HASSTEP && p_var->step.f_float )
1363 float f_round = p_var->step.f_float * (float)(int)( 0.5 +
1364 p_val->f_float / p_var->step.f_float );
1365 if( p_val->f_float != f_round )
1367 p_val->f_float = f_round;
1370 if( p_var->i_type & VLC_VAR_HASMIN
1371 && p_val->f_float < p_var->min.f_float )
1373 p_val->f_float = p_var->min.f_float;
1375 if( p_var->i_type & VLC_VAR_HASMAX
1376 && p_val->f_float > p_var->max.f_float )
1378 p_val->f_float = p_var->max.f_float;
1387 /*****************************************************************************
1388 * InheritValue: try to inherit the value of this variable from the same one
1389 * in our closest parent, libvlc or ultimately from the configuration.
1390 * The function should always be entered with the object var_lock locked.
1391 *****************************************************************************/
1392 static int InheritValue( vlc_object_t *p_this, const char *psz_name,
1393 vlc_value_t *p_val, int i_type )
1398 if( p_this->p_parent || ( p_this->p_libvlc && p_this != (vlc_object_t*) p_this->p_libvlc ) )
1400 vlc_object_internals_t *p_priv;
1402 if( p_this->p_parent )
1403 p_priv = vlc_internals( p_this->p_parent );
1405 p_priv = vlc_internals( p_this->p_libvlc );
1407 i_var = Lookup( p_priv->p_vars, p_priv->i_vars, psz_name );
1412 p_var = &p_priv->p_vars[i_var];
1414 /* Really get the variable */
1415 *p_val = p_var->val;
1417 /* Duplicate value if needed */
1418 p_var->ops->pf_dup( p_val );
1420 /*msg_Dbg( p_this, "Inherited value for var %s from object %s",
1421 psz_name ? psz_name : "(null)",
1422 p_this->psz_object_name
1423 ? p_this->psz_object_name : "(Unknown)" );*/
1426 else if ( p_this->p_parent ) /* We are still not there */
1427 return InheritValue( p_this->p_parent, psz_name, p_val, i_type );
1429 /* else take value from config */
1433 switch( i_type & VLC_VAR_CLASS )
1435 case VLC_VAR_STRING:
1436 p_val->psz_string = config_GetPsz( p_this, psz_name );
1437 if( !p_val->psz_string ) p_val->psz_string = strdup("");
1440 p_val->f_float = config_GetFloat( p_this, psz_name );
1442 case VLC_VAR_INTEGER:
1443 p_val->i_int = config_GetInt( p_this, psz_name );
1446 p_val->b_bool = config_GetInt( p_this, psz_name );
1450 char *psz_orig, *psz_var;
1451 vlc_list_t *p_list = malloc(sizeof(vlc_list_t));
1452 p_val->p_list = p_list;
1453 p_list->i_count = 0;
1455 psz_var = psz_orig = config_GetPsz( p_this, psz_name );
1456 while( psz_var && *psz_var )
1458 char *psz_item = psz_var;
1460 while( *psz_var && *psz_var != ',' ) psz_var++;
1461 if( *psz_var == ',' )
1466 val.i_int = strtol( psz_item, NULL, 0 );
1467 INSERT_ELEM( p_list->p_values, p_list->i_count,
1468 p_list->i_count, val );
1469 /* p_list->i_count is incremented twice by INSERT_ELEM */
1471 INSERT_ELEM( p_list->pi_types, p_list->i_count,
1472 p_list->i_count, VLC_VAR_INTEGER );
1478 msg_Warn( p_this, "Could not inherit value for var %s "
1479 "from config. Invalid Type", psz_name );
1483 /*msg_Dbg( p_this, "Inherited value for var %s from config", psz_name );*/
1488 /**********************************************************************
1489 * Trigger the callbacks.
1490 * Tell we're in a callback, release the lock, call stored functions,
1492 **********************************************************************/
1493 static int TriggerCallback( vlc_object_t *p_this, variable_t **pp_var,
1494 const char *psz_name, vlc_value_t oldval )
1497 int i_entries = (*pp_var)->i_entries;
1498 callback_entry_t *p_entries = (*pp_var)->p_entries;
1499 vlc_object_internals_t *p_priv = vlc_internals( p_this );
1501 (*pp_var)->b_incallback = true;
1502 vlc_mutex_unlock( &p_priv->var_lock );
1504 /* The real calls */
1505 for( ; i_entries-- ; )
1507 p_entries[i_entries].pf_callback( p_this, psz_name, oldval, (*pp_var)->val,
1508 p_entries[i_entries].p_data );
1511 vlc_mutex_lock( &p_priv->var_lock );
1513 i_var = Lookup( p_priv->p_vars, p_priv->i_vars, psz_name );
1516 msg_Err( p_this, "variable %s has disappeared", psz_name );
1520 *pp_var = &p_priv->p_vars[i_var];
1521 (*pp_var)->b_incallback = false;
1522 vlc_cond_broadcast( &p_priv->var_wait );
1528 /**********************************************************************
1529 * Execute a var command on an object identified by its name
1530 **********************************************************************/
1531 int __var_Command( vlc_object_t *p_this, const char *psz_name,
1532 const char *psz_cmd, const char *psz_arg, char **psz_msg )
1534 vlc_object_t *p_obj = vlc_object_find_name( p_this->p_libvlc,
1535 psz_name, FIND_CHILD );
1541 *psz_msg = strdup( "Unknown destination object." );
1545 i_type = var_Type( p_obj, psz_cmd );
1546 if( !( i_type&VLC_VAR_ISCOMMAND ) )
1548 vlc_object_release( p_obj );
1550 *psz_msg = strdup( "Variable doesn't exist or isn't a command." );
1551 return VLC_EGENERIC;
1554 i_type &= VLC_VAR_CLASS;
1557 case VLC_VAR_INTEGER:
1558 i_ret = var_SetInteger( p_obj, psz_cmd, atoi( psz_arg ) );
1561 i_ret = var_SetFloat( p_obj, psz_cmd, atof( psz_arg ) );
1563 case VLC_VAR_STRING:
1564 i_ret = var_SetString( p_obj, psz_cmd, psz_arg );
1567 i_ret = var_SetBool( p_obj, psz_cmd, atoi( psz_arg ) );
1570 i_ret = VLC_EGENERIC;
1574 vlc_object_release( p_obj );
1578 if( asprintf( psz_msg, "%s on object %s returned %i (%s)",
1579 psz_cmd, psz_name, i_ret, vlc_error( i_ret ) ) == -1)
1588 * Free a list and the associated strings
1589 * @param p_val: the list variable
1590 * @param p_val2: the variable associated or NULL
1592 void var_FreeList( vlc_value_t *p_val, vlc_value_t *p_val2 )
1595 if( p_val2 && p_val2->p_list )
1597 for( int i = 0; i < p_val2->p_list->i_count; i++ )
1598 free( p_val2->p_list->p_values[i].psz_string );
1599 if( p_val2->p_list->i_count )
1601 free( p_val2->p_list->p_values );
1602 free( p_val2->p_list->pi_types );
1604 free( p_val2->p_list );