content/common/child_process_host_impl.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_COMMON_CHILD_PROCESS_HOST_IMPL_H_
   6 #define CONTENT_COMMON_CHILD_PROCESS_HOST_IMPL_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "build/build_config.h"
  12
  13 #include "base/basictypes.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/memory/shared_memory.h"
  16 #include "base/memory/singleton.h"
  17 #include "base/process/process.h"
  18 #include "base/strings/string16.h"
  19 #include "content/public/common/child_process_host.h"
  20 #include "ipc/ipc_listener.h"
  21 #include "ui/gfx/gpu_memory_buffer.h"
  22
  23 namespace base {
  24 class FilePath;
  25 }
  26
  27 namespace IPC {
  28 class MessageFilter;
  29 }
  30
  31 namespace content {
  32 class ChildProcessHostDelegate;
  33
  34 // Provides common functionality for hosting a child process and processing IPC
  35 // messages between the host and the child process. Users are responsible
  36 // for the actual launching and terminating of the child processes.
  37 class CONTENT_EXPORT ChildProcessHostImpl : public ChildProcessHost,
  38                                             public IPC::Listener {
  39  public:
  40   ~ChildProcessHostImpl() override;
  41
  42   // Public and static for reuse by RenderMessageFilter.
  43   static void AllocateSharedMemory(
  44       size_t buffer_size, base::ProcessHandle child_process,
  45       base::SharedMemoryHandle* handle);
  46
  47   // Returns a unique ID to identify a child process. On construction, this
  48   // function will be used to generate the id_, but it is also used to generate
  49   // IDs for the RenderProcessHost, which doesn't inherit from us, and whose IDs
  50   // must be unique for all child processes.
  51   //
  52   // This function is threadsafe since RenderProcessHost is on the UI thread,
  53   // but normally this will be used on the IO thread.
  54   //
  55   // This will never return ChildProcessHost::kInvalidUniqueID.
  56   static int GenerateChildProcessUniqueId();
  57
  58   // Derives a tracing process id from a child process id. Child process ids
  59   // cannot be used directly in child process for tracing due to security
  60   // reasons (see: discussion in crrev.com/1173263004). This method is meant to
  61   // be used when tracing for identifying cross-process shared memory from a
  62   // process which knows the child process id of its endpoints. The value
  63   // returned by this method is guaranteed to be equal to the value returned by
  64   // MemoryDumpManager::GetTracingProcessId() in the corresponding child
  65   // process.
  66   //
  67   // Never returns MemoryDumpManager::kInvalidTracingProcessId.
  68   // Returns only ChildProcessHost::kBrowserTracingProcessId in single-process
  69   // mode.
  70   static uint64 ChildProcessUniqueIdToTracingProcessId(int child_process_id);
  71
  72   // ChildProcessHost implementation
  73   bool Send(IPC::Message* message) override;
  74   void ForceShutdown() override;
  75   std::string CreateChannel() override;
  76   bool IsChannelOpening() override;
  77   void AddFilter(IPC::MessageFilter* filter) override;
  78 #if defined(OS_POSIX)
  79   base::ScopedFD TakeClientFileDescriptor() override;
  80 #endif
  81
  82  private:
  83   friend class ChildProcessHost;
  84
  85   explicit ChildProcessHostImpl(ChildProcessHostDelegate* delegate);
  86
  87   // IPC::Listener methods:
  88   bool OnMessageReceived(const IPC::Message& msg) override;
  89   void OnChannelConnected(int32 peer_pid) override;
  90   void OnChannelError() override;
  91   void OnBadMessageReceived(const IPC::Message& message) override;
  92
  93   // Message handlers:
  94   void OnShutdownRequest();
  95   void OnAllocateSharedMemory(uint32 buffer_size,
  96                               base::SharedMemoryHandle* handle);
  97   void OnAllocateGpuMemoryBuffer(gfx::GpuMemoryBufferId id,
  98                                  uint32 width,
  99                                  uint32 height,
 100                                  gfx::BufferFormat format,
 101                                  gfx::BufferUsage usage,
 102                                  gfx::GpuMemoryBufferHandle* handle);
 103   void OnDeletedGpuMemoryBuffer(gfx::GpuMemoryBufferId id,
 104                                 uint32 sync_point);
 105
 106   ChildProcessHostDelegate* delegate_;
 107   base::Process peer_process_;
 108   bool opening_channel_;  // True while we're waiting the channel to be opened.
 109   scoped_ptr<IPC::Channel> channel_;
 110   std::string channel_id_;
 111
 112   // Holds all the IPC message filters.  Since this object lives on the IO
 113   // thread, we don't have a IPC::ChannelProxy and so we manage filters
 114   // manually.
 115   std::vector<scoped_refptr<IPC::MessageFilter> > filters_;
 116
 117   DISALLOW_COPY_AND_ASSIGN(ChildProcessHostImpl);
 118 };
 119
 120 }  // namespace content
 121
 122 #endif  // CONTENT_COMMON_CHILD_PROCESS_HOST_IMPL_H_