Added version 0.1 from V.

crcutil-1.0/tests/aligned_alloc.h

@@ -0,0 +1,66 @@
+// Copyright 2010 Google Inc.  All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Poor man's platform-independent implementation of aligned memory allocator.
+
+#ifndef CRCUTIL_ALIGNED_ALLOC_H_
+#define CRCUTIL_ALIGNED_ALLOC_H_
+
+#include "std_headers.h"    // size_t, ptrdiff_t
+
+namespace crcutil {
+
+// Allocates a block of memory of "size" bytes so that a field
+// at "field_offset" is aligned on "align" boundary.
+//
+// NB #1: "align" shall be exact power of two.
+//
+// NB #2: memory allocated by AlignedAlloc should be release by AlignedFree().
+//
+inline void *AlignedAlloc(size_t size,
+                          size_t field_offset,
+                          size_t align,
+                          const void **allocated_mem) {
+  if (align == 0 || (align & (align - 1)) != 0 || align < sizeof(char *)) {
+    align = sizeof(*allocated_mem);
+  }
+  size += align - 1 + sizeof(*allocated_mem);
+  char *allocated_memory = new char[size];
+  char *aligned_memory = allocated_memory + sizeof(*allocated_mem);
+  field_offset &= align - 1;
+  size_t actual_alignment =
+      reinterpret_cast<size_t>(aligned_memory + field_offset) & (align - 1);
+  if (actual_alignment != 0) {
+    aligned_memory += align - actual_alignment;
+  }
+  reinterpret_cast<char **>(aligned_memory)[-1] = allocated_memory;
+
+  if (allocated_mem != NULL) {
+    *allocated_mem = allocated_memory;
+  }
+
+  return aligned_memory;
+}
+
+// Frees memory allocated by AlignedAlloc().
+inline void AlignedFree(void *aligned_memory) {
+  if (aligned_memory != NULL) {
+    char *allocated_memory = reinterpret_cast<char **>(aligned_memory)[-1];
+    delete[] allocated_memory;
+  }
+}
+
+}  // namespace crcutil
+
+#endif  // CRCUTIL_ALIGNED_ALLOC_H_