Media library CRUD operations

modules/media_library/sql_delete.c

+/*****************************************************************************
+ * sql_delete.c: SQL-based media library: all database delete functions
+ *****************************************************************************
+ * Copyright (C) 2008-2010 The VideoLAN Team and AUTHORS
+ * $Id$
+ *
+ * Authors: Antoine Lejeune <phytos@videolan.org>
+ *          Jean-Philippe André <jpeg@videolan.org>
+ *          Rémi Duraffort <ivoire@videolan.org>
+ *          Adrien Maglo <magsoft@videolan.org>
+ *          Srikanth Raju <srikiraju at gmail dot com>
+ *
+ * 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.
+ *****************************************************************************/
+
+#include "sql_media_library.h"
+
+
+/**
+ * @brief Generic DELETE function for many medias
+ * Delete a media and all its referencies which don't point
+ * an anything else.
+ *
+ * @param p_ml This media_library_t object
+ * @param p_array list of ids to delete
+ * @return VLC_SUCCESS or VLC_EGENERIC
+ * TODO: Expand to delete media/artist/album given any params
+ */
+int Delete( media_library_t *p_ml, vlc_array_t *p_array )
+{
+    char *psz_idlist = NULL, *psz_tmp = NULL;
+    int i_return = VLC_ENOMEM;
+
+    int i_rows = 0, i_cols = 0;
+    char **pp_results = NULL;
+
+    if( vlc_array_count( p_array ) <= 0 )
+    {
+        i_return = VLC_SUCCESS;
+        goto quit_delete_final;
+    }
+    for( int i = 0; i < vlc_array_count( p_array ); i++ )
+    {
+        ml_element_t* find = ( ml_element_t * )
+            vlc_array_item_at_index( p_array, i );
+        assert( find->criteria == ML_ID );
+        if( !psz_idlist )
+        {
+            if( asprintf( &psz_tmp, "( %d", find->value.i ) == -1)
+            {
+                goto quit_delete_final;
+            }
+        }
+        else
+        {
+            if( asprintf( &psz_tmp, "%s, %d", psz_idlist,
+                    find->value.i ) == -1)
+            {
+                goto quit_delete_final;
+            }
+        }
+        free( psz_idlist );
+        psz_idlist = psz_tmp;
+        psz_tmp = NULL;
+    }
+    free( psz_tmp );
+    if( asprintf( &psz_tmp, "%s )", psz_idlist ? psz_idlist : "(" ) == -1 )
+    {
+        goto quit_delete_final;
+    }
+    psz_idlist = psz_tmp;
+    psz_tmp = NULL;
+
+    msg_Dbg( p_ml, "Multi Delete id list: %s", psz_idlist );
+
+    /**
+     * Below ensures you are emitting media-deleted only
+     * for existant media
+     */
+    Begin( p_ml );
+    i_return = Query( p_ml, &pp_results, &i_rows, &i_cols,
+            "SELECT id FROM media WHERE id IN %s", psz_idlist );
+    if( i_return != VLC_SUCCESS )
+        goto quit;
+
+    i_return = QuerySimple( p_ml,
+            "DELETE FROM media WHERE media.id IN %s", psz_idlist );
+    if( i_return != VLC_SUCCESS )
+        goto quit;
+
+    i_return = QuerySimple( p_ml,
+            "DELETE FROM extra WHERE extra.id IN %s", psz_idlist );
+    if( i_return != VLC_SUCCESS )
+        goto quit;
+
+quit:
+    if( i_return == VLC_SUCCESS )
+    {
+        Commit( p_ml );
+        /* Emit delete on var media-deleted */
+        for( int i = 1; i <= i_rows; i++ )
+        {
+            var_SetInteger( p_ml, "media-deleted", atoi( pp_results[i*i_cols] ) );
+        }
+    }
+    else
+        Rollback( p_ml );
+quit_delete_final:
+    FreeSQLResult( p_ml, pp_results );
+    free( psz_tmp );
+    free( psz_idlist );
+    return i_return;
+}