xbmc/platform/posix/utils/SharedMemory.h

   1 /*
   2  *  Copyright (C) 2017-2018 Team Kodi
   3  *  This file is part of Kodi - https://kodi.tv
   4  *
   5  *  SPDX-License-Identifier: GPL-2.0-or-later
   6  *  See LICENSES/README.md for more information.
   7  */
   8
   9 #pragma once
  10
  11 #include "FileHandle.h"
  12 #include "Mmap.h"
  13
  14 #include <memory>
  15
  16 namespace KODI
  17 {
  18 namespace UTILS
  19 {
  20 namespace POSIX
  21 {
  22
  23 /**
  24  * Get a chunk of shared memory of specified size
  25  *
  26  * The shared memory is automatically allocated, truncated to the correct size
  27  * and memory-mapped.
  28  */
  29 class CSharedMemory
  30 {
  31 public:
  32   explicit CSharedMemory(std::size_t size);
  33
  34   std::size_t Size() const
  35   {
  36     return m_size;
  37   }
  38   void* Data() const
  39   {
  40     return m_mmap.Data();
  41   }
  42   int Fd() const
  43   {
  44     return m_fd;
  45   }
  46
  47 private:
  48   CSharedMemory(CSharedMemory const& other) = delete;
  49   CSharedMemory& operator=(CSharedMemory const& other) = delete;
  50
  51   CFileHandle Open();
  52   CFileHandle OpenMemfd();
  53   CFileHandle OpenShm();
  54
  55   std::size_t m_size;
  56   CFileHandle m_fd;
  57   CMmap m_mmap;
  58 };
  59
  60 }
  61 }
  62 }