ipc/glue/SharedMemoryBasic_chromium.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_ipc_SharedMemoryBasic_chromium_h
   8 #define mozilla_ipc_SharedMemoryBasic_chromium_h
   9
  10 #include "base/shared_memory.h"
  11 #include "mozilla/ipc/SharedMemory.h"
  12
  13 #ifdef FUZZING
  14 #  include "mozilla/ipc/SharedMemoryFuzzer.h"
  15 #endif
  16
  17 #include "nsDebug.h"
  18
  19 //
  20 // This is a low-level wrapper around platform shared memory.  Don't
  21 // use it directly; use Shmem allocated through IPDL interfaces.
  22 //
  23
  24 namespace mozilla {
  25 namespace ipc {
  26
  27 class SharedMemoryBasic final
  28     : public SharedMemoryCommon<base::SharedMemoryHandle> {
  29  public:
  30   SharedMemoryBasic() = default;
  31
  32   virtual bool SetHandle(Handle aHandle, OpenRights aRights) override {
  33     return mSharedMemory.SetHandle(std::move(aHandle),
  34                                    aRights == RightsReadOnly);
  35   }
  36
  37   virtual bool Create(size_t aNbytes) override {
  38     bool ok = mSharedMemory.Create(aNbytes);
  39     if (ok) {
  40       Created(aNbytes);
  41     }
  42     return ok;
  43   }
  44
  45   virtual bool Map(size_t nBytes, void* fixed_address = nullptr) override {
  46     bool ok = mSharedMemory.Map(nBytes, fixed_address);
  47     if (ok) {
  48       Mapped(nBytes);
  49     }
  50     return ok;
  51   }
  52
  53   virtual void Unmap() override { mSharedMemory.Unmap(); }
  54
  55   virtual void CloseHandle() override { mSharedMemory.Close(false); }
  56
  57   virtual void* memory() const override {
  58 #ifdef FUZZING
  59     return SharedMemoryFuzzer::MutateSharedMemory(mSharedMemory.memory(),
  60                                                   mAllocSize);
  61 #else
  62     return mSharedMemory.memory();
  63 #endif
  64   }
  65
  66   static Handle NULLHandle() { return base::SharedMemory::NULLHandle(); }
  67
  68   virtual bool IsHandleValid(const Handle& aHandle) const override {
  69     return base::SharedMemory::IsHandleValid(aHandle);
  70   }
  71
  72   virtual Handle CloneHandle() override { return mSharedMemory.CloneHandle(); }
  73
  74   static void* FindFreeAddressSpace(size_t size) {
  75     return base::SharedMemory::FindFreeAddressSpace(size);
  76   }
  77
  78  private:
  79   ~SharedMemoryBasic() = default;
  80
  81   base::SharedMemory mSharedMemory;
  82 };
  83
  84 }  // namespace ipc
  85 }  // namespace mozilla
  86
  87 #endif  // ifndef mozilla_ipc_SharedMemoryBasic_chromium_h