1 files changed, 78 insertions, 0 deletions
diff --git a/src/common/shuffle.c b/src/common/shuffle.c
new file mode 100644
index 0000000..6b20866
--- /dev/null
+++ b/src/common/shuffle.c
@@ -0,0 +1,78 @@
+
+/* Chrysalide - Outil d'analyse de fichiers binaires
+ * shuffle.c - permtutation aléatoire des éléments d'un ensemble fini
+ *
+ * Copyright (C) 2016 Cyrille Bagard
+ *
+ *  This file is part of Chrysalide.
+ *
+ *  OpenIDA 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  OpenIDA 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 Foobar.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include "shuffle.h"
+
+
+#include <malloc.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+
+/******************************************************************************
+*                                                                             *
+*  Paramètres  : panel = instance d'objet GLib à traiter.                     *
+*                                                                             *
+*  Description : Mélange le contenu d'une liste.                              *
+*                                                                             *
+*  Retour      : -                                                            *
+*                                                                             *
+*  Remarques   : -                                                            *
+*                                                                             *
+******************************************************************************/
+
+void shuffle(void *base, size_t nmemb, size_t size)
+{
+    char *list;                             /* Conversion pour le confort  */
+    char *tmp;                              /* Lieu de transition          */
+    size_t i;                               /* Boucle de parcours          */
+    size_t j;                               /* Emplacement aléatoire       */
+
+    /**
+     * Application de l'algorithme Fisher-Yates.
+     *
+     * Cf. https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
+     */
+
+    if (nmemb > 1)
+    {
+        list = (char *)base;
+
+        tmp = malloc(size);
+
+        for (i = 0; i < (nmemb - 1); i++)
+        {
+            j = i + rand() % (nmemb - i);
+
+            memcpy(tmp, list + i * size, size);
+            memcpy(list + i * size, list + j * size, size);
+            memcpy(list + j * size, tmp, size);
+
+        }
+
+        free(tmp);
+
+    }
+
+}