git.sesse.net Git - vlc/blob - modules/codec/cmml/history.c

   1 /*****************************************************************************
   2  * history.c: vlc_history_t (web-browser-like back/forward history) handling
   3  *****************************************************************************
   4  * Copyright (C) 2004 Commonwealth Scientific and Industrial Research
   5  *                    Organisation (CSIRO) Australia
   6  * Copyright (C) 2004 the VideoLAN team
   7  *
   8  * $Id$
   9  *
  10  * Authors: Andre Pang <Andre.Pang@csiro.au>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc/vlc.h>
  32 #include <vlc_input.h>
  33
  34 #include "history.h"
  35
  36 #include "xarray.h"
  37
  38 #ifdef HAVE_STDLIB_H
  39 #   include <stdlib.h>                                          /* realloc() */
  40 #endif
  41
  42 #undef HISTORY_DEBUG
  43
  44 /*****************************************************************************
  45  * Local prototypes
  46  *****************************************************************************/
  47 static void history_Dump( history_t *p_history );
  48
  49 /*****************************************************************************
  50  * Local structure lock
  51  *****************************************************************************/
  52
  53 /*****************************************************************************
  54  * Actual history code
  55  *****************************************************************************/
  56
  57 history_t *history_New( void )
  58 {
  59    history_t *p_new_history;
  60
  61    p_new_history = calloc( 1, sizeof( struct history_t ) );
  62    if( p_new_history == NULL ) return NULL;
  63
  64    p_new_history->p_xarray = xarray_New( 0 );
  65    if( p_new_history->p_xarray == NULL )
  66    {
  67        free( p_new_history );
  68        return NULL;
  69    }
  70
  71 #ifndef HISTORY_DEBUG
  72    /* make dummy reference to history_Dump to avoid compiler warnings */
  73    while (0)
  74    {
  75        void *p_tmp;
  76
  77        p_tmp = history_Dump;
  78    }
  79 #endif
  80
  81    return p_new_history;
  82 }
  83
  84 bool history_GoBackSavingCurrentItem ( history_t *p_history,
  85                                              history_item_t *p_item )
  86 {
  87     history_PruneAndInsert( p_history, p_item );
  88
  89     /* PruneAndInsert will increment the index, so we need to go
  90      * back one position to reset the index to the place we were at
  91      * before saving the current state, and then go back one more to
  92      * actually go back */
  93     p_history->i_index -= 2;
  94
  95 #ifdef HISTORY_DEBUG
  96     history_Dump( p_history );
  97 #endif
  98     return true;
  99 }
 100
 101 static void history_Dump( history_t *p_history )
 102 {
 103     unsigned int i_count;
 104     int i;
 105
 106     if( xarray_Count( p_history->p_xarray, &i_count ) != XARRAY_SUCCESS )
 107         return;
 108
 109     for (i = 0; i < (int) i_count; i++)
 110     {
 111         history_item_t *p_item;
 112         void *pv_item;
 113
 114         xarray_ObjectAtIndex( p_history->p_xarray, i, &pv_item );
 115
 116         p_item = (history_item_t *) pv_item;
 117
 118         if( p_item == NULL )
 119             fprintf( stderr, "HISTORY: [%d] NULL\n", i );
 120         else
 121         {
 122             fprintf( stderr, "HISTORY: [%d] %p (%p->%s)\n", i, p_item,
 123                      p_item->psz_uri, p_item->psz_uri );
 124         }
 125     }
 126 }
 127
 128 bool history_GoForwardSavingCurrentItem ( history_t *p_history,
 129                                                 history_item_t *p_item )
 130 {
 131 #ifdef HISTORY_DEBUG
 132     history_Dump( p_history );
 133 #endif
 134
 135     if( xarray_ReplaceObject( p_history->p_xarray, p_history->i_index, p_item )
 136         == XARRAY_SUCCESS )
 137     {
 138         p_history->i_index++;
 139         return true;
 140     }
 141     else
 142     {
 143         return false;
 144     }
 145 }
 146
 147 bool history_CanGoBack( history_t *p_history )
 148 {
 149     if( p_history->i_index > 0 )
 150         return true;
 151     else
 152         return false;
 153 }
 154
 155 bool history_CanGoForward( history_t *p_history )
 156 {
 157     unsigned int i_count;
 158
 159     if( xarray_Count( p_history->p_xarray, &i_count ) != XARRAY_SUCCESS )
 160         return false;
 161
 162     if( p_history->i_index < i_count )
 163         return true;
 164     else
 165         return false;
 166 }
 167
 168 history_item_t *history_Item( history_t *p_history )
 169 {
 170     history_item_t *p_item;
 171     void *pv_item;
 172
 173     if( xarray_ObjectAtIndex( p_history->p_xarray, p_history->i_index,
 174                               &pv_item )
 175         == XARRAY_SUCCESS )
 176     {
 177         p_item = (history_item_t *) pv_item;
 178         return p_item;
 179     }
 180     else
 181     {
 182         return NULL;
 183     }
 184 }
 185
 186 void history_Prune( history_t *p_history )
 187 {
 188     xarray_RemoveObjectsAfter( p_history->p_xarray, p_history->i_index );
 189     xarray_RemoveObject( p_history->p_xarray, p_history->i_index );
 190 }
 191
 192 void history_PruneAndInsert( history_t *p_history, history_item_t *p_item )
 193 {
 194     unsigned int i_count;
 195
 196     xarray_Count( p_history->p_xarray, &i_count );
 197
 198     if( i_count == 0 )
 199     {
 200         xarray_InsertObject( p_history->p_xarray, p_item, 0 );
 201         p_history->i_index = 1;
 202     }
 203     else
 204     {
 205         history_Prune( p_history );
 206         xarray_InsertObject( p_history->p_xarray, p_item, p_history->i_index );
 207         p_history->i_index++;
 208     }
 209 }
 210
 211 unsigned int history_Count( history_t *p_history )
 212 {
 213     unsigned int i_count;
 214     xarray_Count( p_history->p_xarray, &i_count );
 215     return i_count;
 216 }
 217
 218 unsigned int history_Index( history_t *p_history )
 219 {
 220     return p_history->i_index;
 221 }
 222
 223 history_item_t * historyItem_New( char *psz_name, char *psz_uri )
 224 {
 225     history_item_t *p_history_item = NULL;
 226
 227     p_history_item = (history_item_t *) malloc( sizeof(history_item_t) );
 228     if( !p_history_item ) return NULL;
 229
 230     p_history_item->psz_uri = strdup( psz_uri );
 231     p_history_item->psz_name = strdup( psz_name );
 232
 233     return p_history_item;
 234 }
 235