Move repositories to 'repos/' subdirectory

This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.

Issue #1082

repos/base/include/util/bit_allocator.h

@@ -0,0 +1,76 @@
+/*
+ * \brief  Allocator using bitmaps
+ * \author Alexander Boettcher
+ * \author Stefan Kalkowski
+ * \date   2012-06-14
+ */
+
+/*
+ * Copyright (C) 2012-2013 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INCLUDE__UTIL__BIT_ALLOCATOR_H_
+#define _INCLUDE__UTIL__BIT_ALLOCATOR_H_
+
+#include <util/bit_array.h>
+
+namespace Genode {
+
+	template<unsigned BITS>
+	class Bit_allocator
+	{
+		protected:
+
+			addr_t          _next;
+			Bit_array<BITS> _array;
+
+			void _reserve(addr_t bit_start, size_t const num)
+			{
+				if (!num) return;
+
+				_array.set(bit_start, num);
+			}
+
+		public:
+
+			class Out_of_indices : Exception {};
+
+			Bit_allocator() : _next(0) { }
+
+			addr_t alloc(size_t const num_log2 = 0)
+			{
+				addr_t const step = 1UL << num_log2;
+				addr_t max = ~0UL;
+
+				do {
+					try {
+						/* throws exception if array is accessed outside bounds */
+						for (addr_t i = _next & ~(step - 1); i < max; i += step) {
+							if (_array.get(i, step))
+								continue;
+
+							_array.set(i, step);
+							_next = i + step;
+							return i;
+						}
+					} catch (typename Bit_array<BITS>::Invalid_index_access) { }
+
+					max = _next;
+					_next = 0;
+
+				} while (max != 0);
+
+				throw Out_of_indices();
+			}
+
+			void free(addr_t const bit_start, size_t const num_log2 = 0)
+			{
+				_array.clear(bit_start, 1UL << num_log2);
+				_next = bit_start;
+			}
+	};
+}
+#endif /* _INCLUDE__UTIL__BIT_ALLOCATOR_H_ */