1 /*****************************************************************************
2 * vlc_arrays.h : Arrays and data structures handling
3 *****************************************************************************
4 * Copyright (C) 1999-2004 VLC authors and VideoLAN
5 * $Id: 39b69952ffce040330da239f52778c3e82024bc4 $
6 *
7 * Authors: Samuel Hocevar <sam@zoy.org>
8 * Clément Stenac <zorglub@videolan.org>
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
24
25 #ifndef VLC_ARRAYS_H_
26 #define VLC_ARRAYS_H_
27
28 /**
29 * \file
30 * This file defines functions, structures and macros for handling arrays in vlc
31 */
32
33 /* realloc() that never fails *if* downsizing */
realloc_down(void * ptr,size_t size)34 static inline void *realloc_down( void *ptr, size_t size )
35 {
36 void *ret = realloc( ptr, size );
37 return ret ? ret : ptr;
38 }
39
40 #define TAB_INIT( count, tab ) \
41 do { \
42 (count) = 0; \
43 (tab) = NULL; \
44 } while(0)
45
46 #define TAB_CLEAN( count, tab ) \
47 do { \
48 free( tab ); \
49 (count)= 0; \
50 (tab)= NULL; \
51 } while(0)
52
53 #define TAB_APPEND_CAST( cast, count, tab, p ) \
54 do { \
55 if( (count) > 0 ) \
56 (tab) = cast realloc( tab, sizeof( *(tab) ) * ( (count) + 1 ) ); \
57 else \
58 (tab) = cast malloc( sizeof( *(tab) ) ); \
59 if( !(tab) ) abort(); \
60 (tab)[count] = (p); \
61 (count)++; \
62 } while(0)
63
64 #define TAB_APPEND( count, tab, p ) \
65 TAB_APPEND_CAST( , count, tab, p )
66
67 #define TAB_FIND( count, tab, p, idx ) \
68 do { \
69 for( (idx) = 0; (idx) < (count); (idx)++ ) \
70 if( (tab)[(idx)] == (p) ) \
71 break; \
72 if( (idx) >= (count) ) \
73 (idx) = -1; \
74 } while(0)
75
76
77 #define TAB_ERASE( count, tab, index ) \
78 do { \
79 if( (count) > 1 ) \
80 memmove( (tab) + (index), \
81 (tab) + (index) + 1, \
82 ((count) - (index) - 1 ) * sizeof( *(tab) ) );\
83 (count)--; \
84 if( (count) == 0 ) \
85 { \
86 free( tab ); \
87 (tab) = NULL; \
88 } \
89 } while(0)
90
91 #define TAB_REMOVE( count, tab, p ) \
92 do { \
93 int i_index; \
94 TAB_FIND( count, tab, p, i_index ); \
95 if( i_index >= 0 ) \
96 TAB_ERASE( count, tab, i_index ); \
97 } while(0)
98
99 #define TAB_INSERT_CAST( cast, count, tab, p, index ) do { \
100 if( (count) > 0 ) \
101 (tab) = cast realloc( tab, sizeof( *(tab) ) * ( (count) + 1 ) ); \
102 else \
103 (tab) = cast malloc( sizeof( *(tab) ) ); \
104 if( !(tab) ) abort(); \
105 if( (count) - (index) > 0 ) \
106 memmove( (tab) + (index) + 1, \
107 (tab) + (index), \
108 ((count) - (index)) * sizeof( *(tab) ) );\
109 (tab)[(index)] = (p); \
110 (count)++; \
111 } while(0)
112
113 #define TAB_INSERT( count, tab, p, index ) \
114 TAB_INSERT_CAST( , count, tab, p, index )
115
116 /**
117 * Binary search in a sorted array. The key must be comparable by < and >
118 * \param entries array of entries
119 * \param count number of entries
120 * \param elem key to check within an entry (like .id, or ->i_id)
121 * \param zetype type of the key
122 * \param key value of the key
123 * \param answer index of answer within the array. -1 if not found
124 */
125 #define BSEARCH( entries, count, elem, zetype, key, answer ) \
126 do { \
127 int low = 0, high = count - 1; \
128 answer = -1; \
129 while( low <= high ) {\
130 int mid = ((unsigned int)low + (unsigned int)high) >> 1;\
131 zetype mid_val = entries[mid] elem;\
132 if( mid_val < key ) \
133 low = mid + 1; \
134 else if ( mid_val > key ) \
135 high = mid -1; \
136 else \
137 { \
138 answer = mid; break; \
139 }\
140 } \
141 } while(0)
142
143
144 /************************************************************************
145 * Dynamic arrays with progressive allocation
146 ************************************************************************/
147
148 /* Internal functions */
149 #define _ARRAY_ALLOC(array, newsize) { \
150 (array).i_alloc = newsize; \
151 (array).p_elems = realloc( (array).p_elems, (array).i_alloc * \
152 sizeof(*(array).p_elems) ); \
153 if( !(array).p_elems ) abort(); \
154 }
155
156 #define _ARRAY_GROW1(array) { \
157 if( (array).i_alloc < 10 ) \
158 _ARRAY_ALLOC(array, 10 ) \
159 else if( (array).i_alloc == (array).i_size ) \
160 _ARRAY_ALLOC(array, (int)((array).i_alloc * 1.5) ) \
161 }
162
163 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
164
165 /* API */
166 #define DECL_ARRAY(type) struct { \
167 int i_alloc; \
168 int i_size; \
169 type *p_elems; \
170 }
171
172 #define TYPEDEF_ARRAY(type, name) typedef DECL_ARRAY(type) name;
173
174 #define ARRAY_INIT(array) \
175 do { \
176 (array).i_alloc = 0; \
177 (array).i_size = 0; \
178 (array).p_elems = NULL; \
179 } while(0)
180
181 #define ARRAY_RESET(array) \
182 do { \
183 (array).i_alloc = 0; \
184 (array).i_size = 0; \
185 free( (array).p_elems ); (array).p_elems = NULL; \
186 } while(0)
187
188 #define ARRAY_APPEND(array, elem) \
189 do { \
190 _ARRAY_GROW1(array); \
191 (array).p_elems[(array).i_size] = elem; \
192 (array).i_size++; \
193 } while(0)
194
195 #define ARRAY_INSERT(array,elem,pos) \
196 do { \
197 _ARRAY_GROW1(array); \
198 if( (array).i_size - pos ) { \
199 memmove( (array).p_elems + pos + 1, (array).p_elems + pos, \
200 ((array).i_size-pos) * sizeof(*(array).p_elems) ); \
201 } \
202 (array).p_elems[pos] = elem; \
203 (array).i_size++; \
204 } while(0)
205
206 #define _ARRAY_SHRINK(array) { \
207 if( (array).i_size > 10 && (array).i_size < (int)((array).i_alloc / 1.5) ) { \
208 _ARRAY_ALLOC(array, (array).i_size + 5); \
209 } \
210 }
211
212 #define ARRAY_REMOVE(array,pos) \
213 do { \
214 if( (array).i_size - (pos) - 1 ) \
215 { \
216 memmove( (array).p_elems + pos, (array).p_elems + pos + 1, \
217 ( (array).i_size - pos - 1 ) *sizeof(*(array).p_elems) ); \
218 } \
219 (array).i_size--; \
220 _ARRAY_SHRINK(array); \
221 } while(0)
222
223 #define ARRAY_VAL(array, pos) array.p_elems[pos]
224
225 #define ARRAY_BSEARCH(array, elem, zetype, key, answer) \
226 BSEARCH( (array).p_elems, (array).i_size, elem, zetype, key, answer)
227
228 #define FOREACH_ARRAY( item, array ) { \
229 int fe_idx; \
230 for( fe_idx = 0 ; fe_idx < (array).i_size ; fe_idx++ ) \
231 { \
232 item = (array).p_elems[fe_idx];
233
234 #define FOREACH_END() } }
235
236
237 /************************************************************************
238 * Dynamic arrays with progressive allocation (Preferred API)
239 ************************************************************************/
240 typedef struct vlc_array_t
241 {
242 size_t i_count;
243 void ** pp_elems;
244 } vlc_array_t;
245
vlc_array_init(vlc_array_t * p_array)246 static inline void vlc_array_init( vlc_array_t * p_array )
247 {
248 p_array->i_count = 0;
249 p_array->pp_elems = NULL;
250 }
251
vlc_array_clear(vlc_array_t * p_array)252 static inline void vlc_array_clear( vlc_array_t * p_array )
253 {
254 free( p_array->pp_elems );
255 vlc_array_init( p_array );
256 }
257
258 /* Read */
vlc_array_count(vlc_array_t * p_array)259 static inline size_t vlc_array_count( vlc_array_t * p_array )
260 {
261 return p_array->i_count;
262 }
263
264 #ifndef __cplusplus
265 # define vlc_array_item_at_index(ar, idx) \
266 _Generic((ar), \
267 const vlc_array_t *: ((ar)->pp_elems[idx]), \
268 vlc_array_t *: ((ar)->pp_elems[idx]))
269 #else
vlc_array_item_at_index(vlc_array_t * ar,size_t idx)270 static inline void *vlc_array_item_at_index( vlc_array_t *ar, size_t idx )
271 {
272 return ar->pp_elems[idx];
273 }
274
vlc_array_item_at_index(const vlc_array_t * ar,size_t idx)275 static inline const void *vlc_array_item_at_index( const vlc_array_t *ar,
276 size_t idx )
277 {
278 return ar->pp_elems[idx];
279 }
280 #endif
281
vlc_array_index_of_item(const vlc_array_t * ar,const void * elem)282 static inline ssize_t vlc_array_index_of_item( const vlc_array_t *ar,
283 const void *elem )
284 {
285 for( size_t i = 0; i < ar->i_count; i++ )
286 {
287 if( ar->pp_elems[i] == elem )
288 return i;
289 }
290 return -1;
291 }
292
293 /* Write */
vlc_array_insert(vlc_array_t * ar,void * elem,int idx)294 static inline int vlc_array_insert( vlc_array_t *ar, void *elem, int idx )
295 {
296 void **pp = (void **)realloc( ar->pp_elems,
297 sizeof( void * ) * (ar->i_count + 1) );
298 if( unlikely(pp == NULL) )
299 return -1;
300
301 size_t tail = ar->i_count - idx;
302 if( tail > 0 )
303 memmove( pp + idx + 1, pp + idx, sizeof( void * ) * tail );
304
305 pp[idx] = elem;
306 ar->i_count++;
307 ar->pp_elems = pp;
308 return 0;
309 }
310
vlc_array_insert_or_abort(vlc_array_t * ar,void * elem,int idx)311 static inline void vlc_array_insert_or_abort( vlc_array_t *ar, void *elem, int idx )
312 {
313 if( vlc_array_insert( ar, elem, idx ) )
314 abort();
315 }
316
vlc_array_append(vlc_array_t * ar,void * elem)317 static inline int vlc_array_append( vlc_array_t *ar, void *elem )
318 {
319 void **pp = (void **)realloc( ar->pp_elems,
320 sizeof( void * ) * (ar->i_count + 1) );
321 if( unlikely(pp == NULL) )
322 return -1;
323
324 pp[ar->i_count++] = elem;
325 ar->pp_elems = pp;
326 return 0;
327 }
328
vlc_array_append_or_abort(vlc_array_t * ar,void * elem)329 static inline void vlc_array_append_or_abort( vlc_array_t *ar, void *elem )
330 {
331 if( vlc_array_append( ar, elem ) != 0 )
332 abort();
333 }
334
vlc_array_remove(vlc_array_t * ar,size_t idx)335 static inline void vlc_array_remove( vlc_array_t *ar, size_t idx )
336 {
337 void **pp = ar->pp_elems;
338 size_t tail = ar->i_count - idx - 1;
339
340 if( tail > 0 )
341 memmove( pp + idx, pp + idx + 1, sizeof( void * ) * tail );
342
343 ar->i_count--;
344
345 if( ar->i_count > 0 )
346 {
347 pp = (void **)realloc( pp, sizeof( void * ) * ar->i_count );
348 if( likely(pp != NULL) )
349 ar->pp_elems = pp;
350 }
351 else
352 {
353 free( pp );
354 ar->pp_elems = NULL;
355 }
356 }
357
358
359 /************************************************************************
360 * Dictionaries
361 ************************************************************************/
362
363 /* This function is not intended to be crypto-secure, we only want it to be
364 * fast and not suck too much. This one is pretty fast and did 0 collisions
365 * in wenglish's dictionary.
366 */
DictHash(const char * psz_string,int hashsize)367 static inline uint64_t DictHash( const char *psz_string, int hashsize )
368 {
369 uint64_t i_hash = 0;
370 if( psz_string )
371 {
372 while( *psz_string )
373 {
374 i_hash += *psz_string++;
375 i_hash += i_hash << 10;
376 i_hash ^= i_hash >> 8;
377 }
378 }
379 return i_hash % hashsize;
380 }
381
382 typedef struct vlc_dictionary_entry_t
383 {
384 char * psz_key;
385 void * p_value;
386 struct vlc_dictionary_entry_t * p_next;
387 } vlc_dictionary_entry_t;
388
389 typedef struct vlc_dictionary_t
390 {
391 int i_size;
392 vlc_dictionary_entry_t ** p_entries;
393 } vlc_dictionary_t;
394
395 static void * const kVLCDictionaryNotFound = NULL;
396
vlc_dictionary_init(vlc_dictionary_t * p_dict,int i_size)397 static inline void vlc_dictionary_init( vlc_dictionary_t * p_dict, int i_size )
398 {
399 p_dict->p_entries = NULL;
400
401 if( i_size > 0 )
402 {
403 p_dict->p_entries = (vlc_dictionary_entry_t **)calloc( i_size, sizeof(*p_dict->p_entries) );
404 if( !p_dict->p_entries )
405 i_size = 0;
406 }
407 p_dict->i_size = i_size;
408 }
409
vlc_dictionary_clear(vlc_dictionary_t * p_dict,void (* pf_free)(void * p_data,void * p_obj),void * p_obj)410 static inline void vlc_dictionary_clear( vlc_dictionary_t * p_dict,
411 void ( * pf_free )( void * p_data, void * p_obj ),
412 void * p_obj )
413 {
414 if( p_dict->p_entries )
415 {
416 for( int i = 0; i < p_dict->i_size; i++ )
417 {
418 vlc_dictionary_entry_t * p_current, * p_next;
419 p_current = p_dict->p_entries[i];
420 while( p_current )
421 {
422 p_next = p_current->p_next;
423 if( pf_free != NULL )
424 ( * pf_free )( p_current->p_value, p_obj );
425 free( p_current->psz_key );
426 free( p_current );
427 p_current = p_next;
428 }
429 }
430 free( p_dict->p_entries );
431 p_dict->p_entries = NULL;
432 }
433 p_dict->i_size = 0;
434 }
435
436 static inline int
vlc_dictionary_has_key(const vlc_dictionary_t * p_dict,const char * psz_key)437 vlc_dictionary_has_key( const vlc_dictionary_t * p_dict, const char * psz_key )
438 {
439 if( !p_dict->p_entries )
440 return 0;
441
442 int i_pos = DictHash( psz_key, p_dict->i_size );
443 const vlc_dictionary_entry_t * p_entry = p_dict->p_entries[i_pos];
444 for( ; p_entry != NULL; p_entry = p_entry->p_next )
445 {
446 if( !strcmp( psz_key, p_entry->psz_key ) )
447 break;
448 }
449 return p_entry != NULL;
450 }
451
452 static inline void *
vlc_dictionary_value_for_key(const vlc_dictionary_t * p_dict,const char * psz_key)453 vlc_dictionary_value_for_key( const vlc_dictionary_t * p_dict, const char * psz_key )
454 {
455 if( !p_dict->p_entries )
456 return kVLCDictionaryNotFound;
457
458 int i_pos = DictHash( psz_key, p_dict->i_size );
459 vlc_dictionary_entry_t * p_entry = p_dict->p_entries[i_pos];
460
461 if( !p_entry )
462 return kVLCDictionaryNotFound;
463
464 /* Make sure we return the right item. (Hash collision) */
465 do {
466 if( !strcmp( psz_key, p_entry->psz_key ) )
467 return p_entry->p_value;
468 p_entry = p_entry->p_next;
469 } while( p_entry );
470
471 return kVLCDictionaryNotFound;
472 }
473
474 static inline int
vlc_dictionary_keys_count(const vlc_dictionary_t * p_dict)475 vlc_dictionary_keys_count( const vlc_dictionary_t * p_dict )
476 {
477 vlc_dictionary_entry_t * p_entry;
478 int i, count = 0;
479
480 if( !p_dict->p_entries )
481 return 0;
482
483 for( i = 0; i < p_dict->i_size; i++ )
484 {
485 for( p_entry = p_dict->p_entries[i]; p_entry; p_entry = p_entry->p_next ) count++;
486 }
487 return count;
488 }
489
490 static inline bool
vlc_dictionary_is_empty(const vlc_dictionary_t * p_dict)491 vlc_dictionary_is_empty( const vlc_dictionary_t * p_dict )
492 {
493 if( p_dict->p_entries )
494 for( int i = 0; i < p_dict->i_size; i++ )
495 if( p_dict->p_entries[i] )
496 return false;
497 return true;
498 }
499
500 static inline char **
vlc_dictionary_all_keys(const vlc_dictionary_t * p_dict)501 vlc_dictionary_all_keys( const vlc_dictionary_t * p_dict )
502 {
503 vlc_dictionary_entry_t * p_entry;
504 char ** ppsz_ret;
505 int i, count = vlc_dictionary_keys_count( p_dict );
506
507 ppsz_ret = (char**)malloc(sizeof(char *) * (count + 1));
508 if( unlikely(!ppsz_ret) )
509 return NULL;
510
511 count = 0;
512 for( i = 0; i < p_dict->i_size; i++ )
513 {
514 for( p_entry = p_dict->p_entries[i]; p_entry; p_entry = p_entry->p_next )
515 ppsz_ret[count++] = strdup( p_entry->psz_key );
516 }
517 ppsz_ret[count] = NULL;
518 return ppsz_ret;
519 }
520
521 static inline void
vlc_dictionary_insert_impl_(vlc_dictionary_t * p_dict,const char * psz_key,void * p_value,bool rebuild)522 vlc_dictionary_insert_impl_( vlc_dictionary_t * p_dict, const char * psz_key,
523 void * p_value, bool rebuild )
524 {
525 if( !p_dict->p_entries )
526 vlc_dictionary_init( p_dict, 1 );
527
528 int i_pos = DictHash( psz_key, p_dict->i_size );
529 vlc_dictionary_entry_t * p_entry;
530
531 p_entry = (vlc_dictionary_entry_t *)malloc(sizeof(*p_entry));
532 p_entry->psz_key = strdup( psz_key );
533 p_entry->p_value = p_value;
534 p_entry->p_next = p_dict->p_entries[i_pos];
535 p_dict->p_entries[i_pos] = p_entry;
536 if( rebuild )
537 {
538 /* Count how many items there was */
539 int count;
540 for( count = 1; p_entry->p_next; count++ )
541 p_entry = p_entry->p_next;
542 if( count > 3 ) /* XXX: this need tuning */
543 {
544 /* Here it starts to be not good, rebuild a bigger dictionary */
545 struct vlc_dictionary_t new_dict;
546 int i_new_size = ( (p_dict->i_size+2) * 3) / 2; /* XXX: this need tuning */
547 int i;
548 vlc_dictionary_init( &new_dict, i_new_size );
549 for( i = 0; i < p_dict->i_size; i++ )
550 {
551 p_entry = p_dict->p_entries[i];
552 while( p_entry )
553 {
554 vlc_dictionary_insert_impl_( &new_dict, p_entry->psz_key,
555 p_entry->p_value,
556 false /* To avoid multiple rebuild loop */);
557 p_entry = p_entry->p_next;
558 }
559 }
560
561 vlc_dictionary_clear( p_dict, NULL, NULL );
562 p_dict->i_size = new_dict.i_size;
563 p_dict->p_entries = new_dict.p_entries;
564 }
565 }
566 }
567
568 static inline void
vlc_dictionary_insert(vlc_dictionary_t * p_dict,const char * psz_key,void * p_value)569 vlc_dictionary_insert( vlc_dictionary_t * p_dict, const char * psz_key, void * p_value )
570 {
571 vlc_dictionary_insert_impl_( p_dict, psz_key, p_value, true );
572 }
573
574 static inline void
vlc_dictionary_remove_value_for_key(const vlc_dictionary_t * p_dict,const char * psz_key,void (* pf_free)(void * p_data,void * p_obj),void * p_obj)575 vlc_dictionary_remove_value_for_key( const vlc_dictionary_t * p_dict, const char * psz_key,
576 void ( * pf_free )( void * p_data, void * p_obj ),
577 void * p_obj )
578 {
579 if( !p_dict->p_entries )
580 return;
581
582 int i_pos = DictHash( psz_key, p_dict->i_size );
583 vlc_dictionary_entry_t * p_entry = p_dict->p_entries[i_pos];
584 vlc_dictionary_entry_t * p_prev;
585
586 if( !p_entry )
587 return; /* Not found, nothing to do */
588
589 /* Hash collision */
590 p_prev = NULL;
591 do {
592 if( !strcmp( psz_key, p_entry->psz_key ) )
593 {
594 if( pf_free != NULL )
595 ( * pf_free )( p_entry->p_value, p_obj );
596 if( !p_prev )
597 p_dict->p_entries[i_pos] = p_entry->p_next;
598 else
599 p_prev->p_next = p_entry->p_next;
600 free( p_entry->psz_key );
601 free( p_entry );
602 return;
603 }
604 p_prev = p_entry;
605 p_entry = p_entry->p_next;
606 } while( p_entry );
607
608 /* No key was found */
609 }
610
611 #ifdef __cplusplus
612 // C++ helpers
613 template <typename T>
vlc_delete_all(T & container)614 void vlc_delete_all( T &container )
615 {
616 typename T::iterator it = container.begin();
617 while ( it != container.end() )
618 {
619 delete *it;
620 ++it;
621 }
622 container.clear();
623 }
624
625 #endif
626
627 #endif
628