/***************************************************************************** * vlc_arrays.h : Arrays and data structures handling ***************************************************************************** * Copyright (C) 1999-2004 the VideoLAN team * $Id: vlc_playlist.h 17108 2006-10-15 15:28:34Z zorglub $ * * Authors: Samuel Hocevar * Clément Stenac * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ #if !defined( __LIBVLC__ ) #error You are not libvlc or one of its plugins. You cannot include this file #endif #ifndef _VLC_ARRAYS_H_ #define _VLC_ARRAYS_H_ #include /** * Simple dynamic array handling. Array is realloced at each insert/removal */ #if defined( _MSC_VER ) && _MSC_VER < 1300 && !defined( UNDER_CE ) # define VLCCVP (void**) /* Work-around for broken compiler */ #else # define VLCCVP #endif #define INSERT_ELEM( p_ar, i_oldsize, i_pos, elem ) \ do \ { \ if( !i_oldsize ) (p_ar) = NULL; \ (p_ar) = VLCCVP realloc( p_ar, ((i_oldsize) + 1) * sizeof(*(p_ar)) ); \ if( (i_oldsize) - (i_pos) ) \ { \ memmove( (p_ar) + (i_pos) + 1, (p_ar) + (i_pos), \ ((i_oldsize) - (i_pos)) * sizeof( *(p_ar) ) ); \ } \ (p_ar)[i_pos] = elem; \ (i_oldsize)++; \ } \ while( 0 ) #define REMOVE_ELEM( p_ar, i_oldsize, i_pos ) \ do \ { \ if( (i_oldsize) - (i_pos) - 1 ) \ { \ memmove( (p_ar) + (i_pos), \ (p_ar) + (i_pos) + 1, \ ((i_oldsize) - (i_pos) - 1) * sizeof( *(p_ar) ) ); \ } \ if( i_oldsize > 1 ) \ { \ (p_ar) = realloc( p_ar, ((i_oldsize) - 1) * sizeof( *(p_ar) ) ); \ } \ else \ { \ free( p_ar ); \ (p_ar) = NULL; \ } \ (i_oldsize)--; \ } \ while( 0 ) #define TAB_INIT( count, tab ) \ do { \ (count) = 0; \ (tab) = NULL; \ } while(0) #define TAB_CLEAN( count, tab ) \ do { \ if( tab ) free( tab ); \ (count)= 0; \ (tab)= NULL; \ } while(0) #define TAB_APPEND_CAST( cast, count, tab, p ) \ do { \ if( (count) > 0 ) \ (tab) = cast realloc( tab, sizeof( void ** ) * ( (count) + 1 ) ); \ else \ (tab) = cast malloc( sizeof( void ** ) ); \ (tab)[count] = (p); \ (count)++; \ } while(0) #define TAB_APPEND( count, tab, p ) \ TAB_APPEND_CAST( , count, tab, p ) #define TAB_APPEND_CPP( type, count, tab, p ) \ TAB_APPEND_CAST( (type**), count, tab, p ) #define TAB_FIND( count, tab, p, index ) \ do { \ int _i_; \ (index) = -1; \ for( _i_ = 0; _i_ < (count); _i_++ ) \ { \ if( (tab)[_i_] == (p) ) \ { \ (index) = _i_; \ break; \ } \ } \ } while(0) #define TAB_REMOVE( count, tab, p ) \ do { \ int _i_index_; \ TAB_FIND( count, tab, p, _i_index_ ); \ if( _i_index_ >= 0 ) \ { \ if( (count) > 1 ) \ { \ memmove( ((void**)(tab) + _i_index_), \ ((void**)(tab) + _i_index_+1), \ ( (count) - _i_index_ - 1 ) * sizeof( void* ) );\ } \ (count)--; \ if( (count) == 0 ) \ { \ free( tab ); \ (tab) = NULL; \ } \ } \ } while(0) #define TAB_INSERT_CAST( cast, count, tab, p, index ) do { \ if( (count) > 0 ) \ (tab) = cast realloc( tab, sizeof( void ** ) * ( (count) + 1 ) ); \ else \ (tab) = cast malloc( sizeof( void ** ) ); \ if( (count) - (index) > 0 ) \ memmove( (void**)(tab) + (index) + 1, \ (void**)(tab) + (index), \ ((count) - (index)) * sizeof(*(tab)) );\ (tab)[(index)] = (p); \ (count)++; \ } while(0) #define TAB_INSERT( count, tab, p, index ) \ TAB_INSERT_CAST( , count, tab, p, index ) /** * Binary search in a sorted array. The key must be comparable by < and > * \param entries array of entries * \param count number of entries * \param elem key to check within an entry (like .id, or ->i_id) * \param zetype type of the key * \param key value of the key * \param answer index of answer within the array. -1 if not found */ #define BSEARCH( entries, count, elem, zetype, key, answer ) \ do { \ int low = 0, high = count - 1; \ answer = -1; \ while( low <= high ) {\ int mid = (low + high ) / 2; /* Just don't care about 2^30 tables */ \ zetype mid_val = entries[mid] elem;\ if( mid_val < key ) \ low = mid + 1; \ else if ( mid_val > key ) \ high = mid -1; \ else \ { \ answer = mid; break; \ }\ } \ } while(0) /************************************************************************ * Dictionaries ************************************************************************/ #ifdef __cplusplus__ extern "C" { #endif /* This function is not intended to be crypto-secure, we only want it to be * fast and not suck too much. This one is pretty fast and did 0 collisions * in wenglish's dictionary. */ static inline uint64_t DictHash( const char *psz_string ) { uint64_t i_hash = 0; if( psz_string ) { while( *psz_string ) { i_hash += *psz_string++; i_hash += i_hash << 10; i_hash ^= i_hash >> 8; } } return i_hash; } typedef struct vlc_dictionary_t { struct vlc_dictionary_entries_t { char * psz_key; uint64_t i_hash; void * p_value; } * p_entries; int i_entries; } vlc_dictionary_t; static void * const kVLCDictionaryNotFound = (void *)-1; static inline void vlc_dictionary_init( vlc_dictionary_t * p_dict ) { p_dict->i_entries = 0; p_dict->p_entries = NULL; } static inline void vlc_dictionary_clear( vlc_dictionary_t * p_dict ) { int i; for ( i = 0; i < p_dict->i_entries; i++ ) { free( p_dict->p_entries[i].psz_key ); } free( p_dict->p_entries ); p_dict->i_entries = 0; p_dict->p_entries = NULL; } static inline void * vlc_dictionary_value_for_key( vlc_dictionary_t * p_dict, const char * psz_key ) { uint64_t i_hash; int i, i_pos; if( p_dict->i_entries == 0 ) return kVLCDictionaryNotFound; i_hash = DictHash( psz_key ); BSEARCH( p_dict->p_entries, p_dict->i_entries, .i_hash, uint64_t, i_hash, i_pos ); if( i_pos == -1 ) return kVLCDictionaryNotFound; /* Hash found, let's check it looks like the entry */ if( !strcmp( psz_key, p_dict->p_entries[i_pos].psz_key ) ) return p_dict->p_entries[i_pos].p_value; /* Hash collision! This should be very rare, but we cannot guarantee * it will never happen. Just do an exhaustive search amongst all * entries with the same hash. */ for( i = i_pos - 1 ; i > 0 && i_hash == p_dict->p_entries[i].i_hash ; i-- ) { if( !strcmp( psz_key, p_dict->p_entries[i].psz_key ) ) return p_dict->p_entries[i_pos].p_value; } for( i = i_pos + 1 ; i < p_dict->i_entries && i_hash == p_dict->p_entries[i].i_hash ; i++ ) { if( !strcmp( psz_key, p_dict->p_entries[i].psz_key )) return p_dict->p_entries[i_pos].p_value; } /* Hash found, but entry not found (shouldn't happen!) */ return kVLCDictionaryNotFound; } static inline void vlc_dictionary_insert( vlc_dictionary_t * p_dict, const char * psz_key, void * p_value ) { uint64_t i_hash = DictHash( psz_key ); int i_new; /* First, caller should take care not to insert twice the same key */ /* This could be removed for optimization */ assert( vlc_dictionary_value_for_key( p_dict, psz_key ) == kVLCDictionaryNotFound ); /* Find a free slot */ if( p_dict->i_entries == 0 || i_hash <= p_dict->p_entries[0].i_hash ) i_new = 0; else if( i_hash >= p_dict->p_entries[p_dict->i_entries-1].i_hash ) i_new = p_dict->i_entries; else { int i_low = 0, i_high = p_dict->i_entries - 1; while( i_high - i_low > 1 ) { int i_mid = (i_low + i_high)/2; if( p_dict->p_entries[i_mid].i_hash < i_hash ) { i_low = i_mid; } else if( p_dict->p_entries[i_mid].i_hash > i_hash ) { i_high = i_mid; } } if( p_dict->p_entries[i_low].i_hash < i_hash ) i_new = i_high; else i_new = i_low; } p_dict->p_entries = realloc( p_dict->p_entries, (p_dict->i_entries + 1) * sizeof(struct vlc_dictionary_entries_t) ); p_dict->i_entries++; if( i_new != p_dict->i_entries -1 ) { memmove( &p_dict->p_entries[i_new+1], &p_dict->p_entries[i_new], ( p_dict->i_entries - i_new - 1 ) * sizeof(struct vlc_dictionary_entries_t) ); } p_dict->p_entries[i_new].i_hash = i_hash; p_dict->p_entries[i_new].psz_key = strdup( psz_key ); p_dict->p_entries[i_new].p_value = p_value; } #ifdef __cplusplus__ } /* extern "C" */ #endif /************************************************************************ * Dynamic arrays with progressive allocation ************************************************************************/ /* Internal functions */ #define _ARRAY_ALLOC(array, newsize) { \ array.i_alloc = newsize; \ array.p_elems = VLCCVP realloc( array.p_elems, array.i_alloc * \ sizeof(*array.p_elems) ); \ assert(array.p_elems); \ } #define _ARRAY_GROW1(array) { \ if( array.i_alloc < 10 ) \ _ARRAY_ALLOC(array, 10 ) \ else if( array.i_alloc == array.i_size ) \ _ARRAY_ALLOC(array, (int)(array.i_alloc * 1.5) ) \ } #define _ARRAY_GROW(array,additional) { \ int i_first = array.i_alloc; \ while( array.i_alloc - i_first < additional ) \ { \ if( array.i_alloc < 10 ) \ _ARRAY_ALLOC(array, 10 ) \ else if( array.i_alloc == array.i_size ) \ _ARRAY_ALLOC(array, (int)(array.i_alloc * 1.5) ) \ else break; \ } \ } #define _ARRAY_SHRINK(array) { \ if( array.i_size > 10 && array.i_size < (int)(array.i_alloc / 1.5) ) { \ _ARRAY_ALLOC(array, array.i_size + 5); \ } \ } /* API */ #define DECL_ARRAY(type) struct { \ int i_alloc; \ int i_size; \ type *p_elems; \ } #define TYPEDEF_ARRAY(type, name) typedef DECL_ARRAY(type) name; #define ARRAY_INIT(array) \ array.i_alloc = 0; \ array.i_size = 0; \ array.p_elems = NULL; #define ARRAY_RESET(array) \ array.i_alloc = 0; \ array.i_size = 0; \ free( array.p_elems ); array.p_elems = NULL; #define ARRAY_APPEND(array, elem) { \ _ARRAY_GROW1(array); \ array.p_elems[array.i_size] = elem; \ array.i_size++; \ } #define ARRAY_INSERT(array,elem,pos) { \ _ARRAY_GROW1(array); \ if( array.i_size - pos ) { \ memmove( array.p_elems + pos + 1, array.p_elems + pos, \ (array.i_size-pos) * sizeof(*array.p_elems) ); \ } \ array.p_elems[pos] = elem; \ array.i_size++; \ } #define ARRAY_REMOVE(array,pos) { \ if( array.i_size - (pos) - 1 ) \ { \ memmove( array.p_elems + pos, array.p_elems + pos + 1, \ ( array.i_size - pos - 1 ) *sizeof(*array.p_elems) ); \ } \ array.i_size--; \ _ARRAY_SHRINK(array); \ } #define ARRAY_VAL(array, pos) array.p_elems[pos] #define ARRAY_BSEARCH(array, elem, zetype, key, answer) \ BSEARCH( array.p_elems, array.i_size, elem, zetype, key, answer) #define FOREACH_ARRAY( item, array ) { \ int fe_idx; \ for( fe_idx = 0 ; fe_idx < array.i_size ; fe_idx++ ) \ { \ item = array.p_elems[fe_idx]; #define FOREACH_END() } } #endif