/*****************************************************************************
* vlc_arrays.h : Arrays and data structures handling
*****************************************************************************
* Copyright (C) 1999-2004 VLC authors and VideoLAN
* $Id: 68ea1e248023b524d76dafedab934f9821541fcc $
*
* Authors: Samuel Hocevar <sam@zoy.org>
* Clément Stenac <zorglub@videolan.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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.
*****************************************************************************/
#ifndef VLC_ARRAYS_H_
#define VLC_ARRAYS_H_
/**
* \file
* This file defines functions, structures and macros for handling arrays in vlc
*/
/* realloc() that never fails *if* downsizing */
static inline void *realloc_down( void *ptr, size_t size )
{
void *ret = realloc( ptr, size );
return ret ? ret : ptr;
}
/**
* 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( !(p_ar) ) abort(); \
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_size, i_pos ) \
do \
{ \
if( (i_size) - (i_pos) - 1 ) \
{ \
memmove( (p_ar) + (i_pos), \
(p_ar) + (i_pos) + 1, \
((i_size) - (i_pos) - 1) * sizeof( *(p_ar) ) ); \
} \
if( i_size > 1 ) \
(p_ar) = realloc_down( p_ar, ((i_size) - 1) * sizeof( *(p_ar) ) );\
else \
{ \
free( p_ar ); \
(p_ar) = NULL; \
} \
(i_size)--; \
} \
while( 0 )
#define TAB_INIT( count, tab ) \
do { \
(count) = 0; \
(tab) = NULL; \
} while(0)
#define TAB_CLEAN( count, tab ) \
do { \
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 ** ) ); \
if( !(tab) ) abort(); \
(tab)[count] = (p); \
(count)++; \
} while(0)
#define TAB_APPEND( count, tab, p ) \
TAB_APPEND_CAST( , count, tab, p )
#define TAB_FIND( count, tab, p, index ) \
do { \
(index) = -1; \
for( int 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( !(tab) ) abort(); \
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)
/************************************************************************
* 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) ); \
if( !(array).p_elems ) abort(); \
}
#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_SIZE(x) (sizeof(x) / sizeof((x)[0]))
/* 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) \
do { \
(array).i_alloc = 0; \
(array).i_size = 0; \
(array).p_elems = NULL; \
} while(0)
#define ARRAY_RESET(array) \
do { \
(array).i_alloc = 0; \
(array).i_size = 0; \
free( (array).p_elems ); (array).p_elems = NULL; \
} while(0)
#define ARRAY_APPEND(array, elem) \
do { \
_ARRAY_GROW1(array); \
(array).p_elems[(array).i_size] = elem; \
(array).i_size++; \
} while(0)
#define ARRAY_INSERT(array,elem,pos) \
do { \
_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++; \
} while(0)
#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); \
} \
}
#define ARRAY_REMOVE(array,pos) \
do { \
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); \
} while(0)
#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() } }
/************************************************************************
* Dynamic arrays with progressive allocation (Preferred API)
************************************************************************/
typedef struct vlc_array_t
{
int i_count;
void ** pp_elems;
} vlc_array_t;
static inline void vlc_array_init( vlc_array_t * p_array )
{
memset( p_array, 0, sizeof(vlc_array_t) );
}
static inline void vlc_array_clear( vlc_array_t * p_array )
{
free( p_array->pp_elems );
memset( p_array, 0, sizeof(vlc_array_t) );
}
static inline vlc_array_t * vlc_array_new( void )
{
vlc_array_t * ret = (vlc_array_t *)malloc( sizeof(vlc_array_t) );
if( ret ) vlc_array_init( ret );
return ret;
}
static inline void vlc_array_destroy( vlc_array_t * p_array )
{
if( !p_array )
return;
vlc_array_clear( p_array );
free( p_array );
}
/* Read */
static inline int
vlc_array_count( vlc_array_t * p_array )
{
return p_array->i_count;
}
static inline void *
vlc_array_item_at_index( vlc_array_t * p_array, int i_index )
{
return p_array->pp_elems[i_index];
}
static inline int
vlc_array_index_of_item( vlc_array_t * p_array, void * item )
{
int i;
for( i = 0; i < p_array->i_count; i++)
{
if( p_array->pp_elems[i] == item )
return i;
}
return -1;
}
/* Write */
static inline void
vlc_array_insert( vlc_array_t * p_array, void * p_elem, int i_index )
{
TAB_INSERT_CAST( (void **), p_array->i_count, p_array->pp_elems, p_elem, i_index );
}
static inline void
vlc_array_append( vlc_array_t * p_array, void * p_elem )
{
vlc_array_insert( p_array, p_elem, p_array->i_count );
}
static inline void
vlc_array_remove( vlc_array_t * p_array, int i_index )
{
if( i_index >= 0 )
{
if( p_array->i_count > 1 )
{
memmove( p_array->pp_elems + i_index,
p_array->pp_elems + i_index+1,
( p_array->i_count - i_index - 1 ) * sizeof( void* ) );
}
p_array->i_count--;
if( p_array->i_count == 0 )
{
free( p_array->pp_elems );
p_array->pp_elems = NULL;
}
}
}
/************************************************************************
* Dictionaries
************************************************************************/
/* 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, int hashsize )
{
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 % hashsize;
}
typedef struct vlc_dictionary_entry_t
{
char * psz_key;
void * p_value;
struct vlc_dictionary_entry_t * p_next;
} vlc_dictionary_entry_t;
typedef struct vlc_dictionary_t
{
int i_size;
vlc_dictionary_entry_t ** p_entries;
} vlc_dictionary_t;
static void * const kVLCDictionaryNotFound = NULL;
static inline void vlc_dictionary_init( vlc_dictionary_t * p_dict, int i_size )
{
p_dict->p_entries = NULL;
if( i_size > 0 )
{
p_dict->p_entries = (vlc_dictionary_entry_t **)calloc( i_size, sizeof(*p_dict->p_entries) );
if( !p_dict->p_entries )
i_size = 0;
}
p_dict->i_size = i_size;
}
static inline void vlc_dictionary_clear( vlc_dictionary_t * p_dict,
void ( * pf_free )( void * p_data, void * p_obj ),
void * p_obj )
{
if( p_dict->p_entries )
{
for( int i = 0; i < p_dict->i_size; i++ )
{
vlc_dictionary_entry_t * p_current, * p_next;
p_current = p_dict->p_entries[i];
while( p_current )
{
p_next = p_current->p_next;
if( pf_free != NULL )
( * pf_free )( p_current->p_value, p_obj );
free( p_current->psz_key );
free( p_current );
p_current = p_next;
}
}
free( p_dict->p_entries );
p_dict->p_entries = NULL;
}
p_dict->i_size = 0;
}
static inline void *
vlc_dictionary_value_for_key( const vlc_dictionary_t * p_dict, const char * psz_key )
{
if( !p_dict->p_entries )
return kVLCDictionaryNotFound;
int i_pos = DictHash( psz_key, p_dict->i_size );
vlc_dictionary_entry_t * p_entry = p_dict->p_entries[i_pos];
if( !p_entry )
return kVLCDictionaryNotFound;
/* Make sure we return the right item. (Hash collision) */
do {
if( !strcmp( psz_key, p_entry->psz_key ) )
return p_entry->p_value;
p_entry = p_entry->p_next;
} while( p_entry );
return kVLCDictionaryNotFound;
}
static inline int
vlc_dictionary_keys_count( const vlc_dictionary_t * p_dict )
{
vlc_dictionary_entry_t * p_entry;
int i, count = 0;
if( !p_dict->p_entries )
return 0;
for( i = 0; i < p_dict->i_size; i++ )
{
for( p_entry = p_dict->p_entries[i]; p_entry; p_entry = p_entry->p_next ) count++;
}
return count;
}
static inline char **
vlc_dictionary_all_keys( const vlc_dictionary_t * p_dict )
{
vlc_dictionary_entry_t * p_entry;
char ** ppsz_ret;
int i, count = vlc_dictionary_keys_count( p_dict );
ppsz_ret = (char**)malloc(sizeof(char *) * (count + 1));
count = 0;
for( i = 0; i < p_dict->i_size; i++ )
{
for( p_entry = p_dict->p_entries[i]; p_entry; p_entry = p_entry->p_next )
ppsz_ret[count++] = strdup( p_entry->psz_key );
}
ppsz_ret[count] = NULL;
return ppsz_ret;
}
static inline void
__vlc_dictionary_insert( vlc_dictionary_t * p_dict, const char * psz_key,
void * p_value, bool rebuild )
{
if( !p_dict->p_entries )
vlc_dictionary_init( p_dict, 1 );
int i_pos = DictHash( psz_key, p_dict->i_size );
vlc_dictionary_entry_t * p_entry;
p_entry = (vlc_dictionary_entry_t *)malloc(sizeof(*p_entry));
p_entry->psz_key = strdup( psz_key );
p_entry->p_value = p_value;
p_entry->p_next = p_dict->p_entries[i_pos];
p_dict->p_entries[i_pos] = p_entry;
if( rebuild )
{
/* Count how many items there was */
int count;
for( count = 1; p_entry->p_next; count++ )
p_entry = p_entry->p_next;
if( count > 3 ) /* XXX: this need tuning */
{
/* Here it starts to be not good, rebuild a bigger dictionary */
struct vlc_dictionary_t new_dict;
int i_new_size = ( (p_dict->i_size+2) * 3) / 2; /* XXX: this need tuning */
int i;
vlc_dictionary_init( &new_dict, i_new_size );
for( i = 0; i < p_dict->i_size; i++ )
{
p_entry = p_dict->p_entries[i];
while( p_entry )
{
__vlc_dictionary_insert( &new_dict, p_entry->psz_key,
p_entry->p_value,
false /* To avoid multiple rebuild loop */);
p_entry = p_entry->p_next;
}
}
vlc_dictionary_clear( p_dict, NULL, NULL );
p_dict->i_size = new_dict.i_size;
p_dict->p_entries = new_dict.p_entries;
}
}
}
static inline void
vlc_dictionary_insert( vlc_dictionary_t * p_dict, const char * psz_key, void * p_value )
{
__vlc_dictionary_insert( p_dict, psz_key, p_value, true );
}
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 )
{
if( !p_dict->p_entries )
return;
int i_pos = DictHash( psz_key, p_dict->i_size );
vlc_dictionary_entry_t * p_entry = p_dict->p_entries[i_pos];
vlc_dictionary_entry_t * p_prev;
if( !p_entry )
return; /* Not found, nothing to do */
/* Hash collision */
p_prev = NULL;
do {
if( !strcmp( psz_key, p_entry->psz_key ) )
{
if( pf_free != NULL )
( * pf_free )( p_entry->p_value, p_obj );
if( !p_prev )
p_dict->p_entries[i_pos] = p_entry->p_next;
else
p_prev->p_next = p_entry->p_next;
free( p_entry->psz_key );
free( p_entry );
return;
}
p_prev = p_entry;
p_entry = p_entry->p_next;
} while( p_entry );
/* No key was found */
}
#ifdef __cplusplus
// C++ helpers
template <typename T>
void vlc_delete_all( T &container )
{
typename T::iterator it = container.begin();
while ( it != container.end() )
{
delete *it;
++it;
}
container.clear();
}
#endif
#endif
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