Filters definition. Example XOR_encrypt filter.

libisofs/filter.c

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2008 Vreixo Formoso
+ * 
+ * This file is part of the libisofs project; you can redistribute it and/or 
+ * modify it under the terms of the GNU General Public License version 2 as 
+ * published by the Free Software Foundation. See COPYING file for details.
+ */
+
+#include "libisofs.h"
+#include "filter.h"
+#include "node.h"
+
+
+void iso_filter_ref(FilterContext *filter)
+{
+    ++filter->refcount;
+}
+
+void iso_filter_unref(FilterContext *filter)
+{
+    if (--filter->refcount == 0) {
+        filter->free(filter);
+        free(filter);
+    }
+}
+
+int iso_file_add_filter(IsoFile *file, FilterContext *filter, int flag)
+{
+    int ret;
+    IsoStream *original, *filtered;
+    if (file == NULL || filter == NULL) {
+        return ISO_NULL_POINTER;
+    }
+    
+    original = file->stream;
+    ret = filter->get_filter(filter, original, &filtered);
+    if (ret < 0) {
+        return ret;
+    }
+    iso_stream_unref(original);
+    file->stream = filtered;
+    return ISO_SUCCESS;
+}