MemoryRegion.h revision affc150dc44fab1911775a49636d0ce85333b634 
1//===- MemoryRegion.h -----------------------------------------------------===//
2//
3//                     The MCLinker Project
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9#ifndef LD_MEMORY_REGION_H
10#define LD_MEMORY_REGION_H
11#ifdef ENABLE_UNITTEST
12#include <gtest.h>
13#endif
14
15#include <mcld/ADT/Uncopyable.h>
16#include <mcld/Support/FileSystem.h>
17#include <mcld/Support/MemoryArea.h>
18#include <mcld/Support/Space.h>
19
20namespace mcld
21{
22
23/** \class MemoryRegion
24 *  \brief MemoryRegion is a range of virtual memory which is mapped onto a
25 *  range of files which is opened by MemoryArea.
26 *
27 *  MemoryArea maps a file onto virtual memory. Clients can get a range of
28 *  mapped memory space by requesting a MemoryRegion from MemoryArea, and
29 *  read/write the mapped file through the MemoryRegion.
30 *
31 *  When two different MemoryRegion may overlap memory space, race condition
32 *  may occurs. Clients must call MemoryRegion::sync() explicit to tell the
33 *  MemoryArea when to synchronize the virtual memory space with the mapped
34 *  file.
35 */
36class MemoryRegion : private Uncopyable
37{
38friend class RegionFactory;
39friend class MemoryArea;
40
41public:
42  typedef Space::Address Address;
43  typedef Space::ConstAddress ConstAddress;
44
45private:
46  MemoryRegion(Space& pParent, const Address pVMAStart, size_t pSize);
47
48  Space* parent()
49  { return &m_Parent; }
50
51  const Space* parent() const
52  { return &m_Parent; }
53
54public:
55  ~MemoryRegion();
56
57  Address start()
58  { return m_VMAStart; }
59
60  ConstAddress start() const
61  { return m_VMAStart; }
62
63  Address end()
64  { return m_VMAStart+m_Length; }
65
66  ConstAddress end() const
67  { return m_VMAStart+m_Length; }
68
69  size_t size() const
70  { return m_Length; }
71
72  Address getBuffer(size_t pOffset = 0)
73  { return m_VMAStart+pOffset; }
74
75  ConstAddress getBuffer(size_t pOffset = 0) const
76  { return m_VMAStart+pOffset; }
77
78private:
79  Space& m_Parent;
80  Address m_VMAStart;
81  size_t m_Length;
82};
83
84} // namespace of mcld
85
86#endif
87
88