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 */
34static inline void *realloc_down( void *ptr, size_t size )
35{
36 void *ret = realloc( ptr: ptr, size: 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 ************************************************************************/
240typedef struct vlc_array_t
241{
242 size_t i_count;
243 void ** pp_elems;
244} vlc_array_t;
245
246static 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
252static inline void vlc_array_clear( vlc_array_t * p_array )
253{
254 free( ptr: p_array->pp_elems );
255 vlc_array_init( p_array );
256}
257
258/* Read */
259static 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
270static inline void *vlc_array_item_at_index( vlc_array_t *ar, size_t idx )
271{
272 return ar->pp_elems[idx];
273}
274
275static 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
282static 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 */
294static inline int vlc_array_insert( vlc_array_t *ar, void *elem, int idx )
295{
296 void **pp = (void **)realloc( ptr: ar->pp_elems,
297 size: 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( dest: pp + idx + 1, src: pp + idx, n: sizeof( void * ) * tail );
304
305 pp[idx] = elem;
306 ar->i_count++;
307 ar->pp_elems = pp;
308 return 0;
309}
310
311static 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
317static inline int vlc_array_append( vlc_array_t *ar, void *elem )
318{
319 void **pp = (void **)realloc( ptr: ar->pp_elems,
320 size: 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
329static 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
335static 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( dest: pp + idx, src: pp + idx + 1, n: sizeof( void * ) * tail );
342
343 ar->i_count--;
344
345 if( ar->i_count > 0 )
346 {
347 pp = (void **)realloc( ptr: pp, size: sizeof( void * ) * ar->i_count );
348 if( likely(pp != NULL) )
349 ar->pp_elems = pp;
350 }
351 else
352 {
353 free( ptr: 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 */
367static 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
382typedef 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
389typedef struct vlc_dictionary_t
390{
391 int i_size;
392 vlc_dictionary_entry_t ** p_entries;
393} vlc_dictionary_t;
394
395static void * const kVLCDictionaryNotFound = NULL;
396
397static 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( nmemb: i_size, 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
410static 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( ptr: p_current->psz_key );
426 free( ptr: p_current );
427 p_current = p_next;
428 }
429 }
430 free( ptr: p_dict->p_entries );
431 p_dict->p_entries = NULL;
432 }
433 p_dict->i_size = 0;
434}
435
436static inline int
437vlc_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_string: psz_key, hashsize: 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( s1: psz_key, s2: p_entry->psz_key ) )
447 break;
448 }
449 return p_entry != NULL;
450}
451
452static inline void *
453vlc_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_string: psz_key, hashsize: 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( s1: psz_key, s2: 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
474static inline int
475vlc_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
490static inline bool
491vlc_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
500static inline char **
501vlc_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(size: 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( s: p_entry->psz_key );
516 }
517 ppsz_ret[count] = NULL;
518 return ppsz_ret;
519}
520
521static inline void
522vlc_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, i_size: 1 );
527
528 int i_pos = DictHash( psz_string: psz_key, hashsize: p_dict->i_size );
529 vlc_dictionary_entry_t * p_entry;
530
531 p_entry = (vlc_dictionary_entry_t *)malloc(size: sizeof(*p_entry));
532 p_entry->psz_key = strdup( s: 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( p_dict: &new_dict, i_size: 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_( p_dict: &new_dict, psz_key: p_entry->psz_key,
555 p_value: p_entry->p_value,
556 rebuild: 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
568static inline void
569vlc_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, rebuild: true );
572}
573
574static inline void
575vlc_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_string: psz_key, hashsize: 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( s1: psz_key, s2: 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( ptr: p_entry->psz_key );
601 free( ptr: 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
613template <typename T>
614void 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

source code of include/vlc/plugins/vlc_arrays.h