mojo/system/core.h

   1 // Copyright 2013 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 MOJO_SYSTEM_CORE_H_
   6 #define MOJO_SYSTEM_CORE_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/memory/ref_counted.h"
  11 #include "base/synchronization/lock.h"
  12 #include "mojo/public/c/system/buffer.h"
  13 #include "mojo/public/c/system/data_pipe.h"
  14 #include "mojo/public/c/system/message_pipe.h"
  15 #include "mojo/public/c/system/types.h"
  16 #include "mojo/system/handle_table.h"
  17 #include "mojo/system/mapping_table.h"
  18 #include "mojo/system/system_impl_export.h"
  19
  20 namespace mojo {
  21 namespace system {
  22
  23 class Dispatcher;
  24
  25 // |Core| is an object that implements the Mojo system calls. All public methods
  26 // are thread-safe.
  27 class MOJO_SYSTEM_IMPL_EXPORT Core {
  28  public:
  29   // These methods are only to be used by via the embedder API (and internally).
  30   Core();
  31   virtual ~Core();
  32
  33   // Adds |dispatcher| to the handle table, returning the handle for it. Returns
  34   // |MOJO_HANDLE_INVALID| on failure, namely if the handle table is full.
  35   MojoHandle AddDispatcher(const scoped_refptr<Dispatcher>& dispatcher);
  36
  37   // Looks up the dispatcher for the given handle. Returns null if the handle is
  38   // invalid.
  39   scoped_refptr<Dispatcher> GetDispatcher(MojoHandle handle);
  40
  41   // System calls implementation.
  42   MojoTimeTicks GetTimeTicksNow();
  43   MojoResult Close(MojoHandle handle);
  44   MojoResult Wait(MojoHandle handle,
  45                   MojoWaitFlags flags,
  46                   MojoDeadline deadline);
  47   MojoResult WaitMany(const MojoHandle* handles,
  48                       const MojoWaitFlags* flags,
  49                       uint32_t num_handles,
  50                       MojoDeadline deadline);
  51   MojoResult CreateMessagePipe(MojoHandle* message_pipe_handle0,
  52                                MojoHandle* message_pipe_handle1);
  53   MojoResult WriteMessage(MojoHandle message_pipe_handle,
  54                           const void* bytes,
  55                           uint32_t num_bytes,
  56                           const MojoHandle* handles,
  57                           uint32_t num_handles,
  58                           MojoWriteMessageFlags flags);
  59   MojoResult ReadMessage(MojoHandle message_pipe_handle,
  60                          void* bytes,
  61                          uint32_t* num_bytes,
  62                          MojoHandle* handles,
  63                          uint32_t* num_handles,
  64                          MojoReadMessageFlags flags);
  65   MojoResult CreateDataPipe(const MojoCreateDataPipeOptions* options,
  66                             MojoHandle* data_pipe_producer_handle,
  67                             MojoHandle* data_pipe_consumer_handle);
  68   MojoResult WriteData(MojoHandle data_pipe_producer_handle,
  69                        const void* elements,
  70                        uint32_t* num_bytes,
  71                        MojoWriteDataFlags flags);
  72   MojoResult BeginWriteData(MojoHandle data_pipe_producer_handle,
  73                             void** buffer,
  74                             uint32_t* buffer_num_bytes,
  75                             MojoWriteDataFlags flags);
  76   MojoResult EndWriteData(MojoHandle data_pipe_producer_handle,
  77                           uint32_t num_bytes_written);
  78   MojoResult ReadData(MojoHandle data_pipe_consumer_handle,
  79                       void* elements,
  80                       uint32_t* num_bytes,
  81                       MojoReadDataFlags flags);
  82   MojoResult BeginReadData(MojoHandle data_pipe_consumer_handle,
  83                            const void** buffer,
  84                            uint32_t* buffer_num_bytes,
  85                            MojoReadDataFlags flags);
  86   MojoResult EndReadData(MojoHandle data_pipe_consumer_handle,
  87                          uint32_t num_bytes_read);
  88   MojoResult CreateSharedBuffer(const MojoCreateSharedBufferOptions* options,
  89                                 uint64_t num_bytes,
  90                                 MojoHandle* shared_buffer_handle);
  91   MojoResult DuplicateBufferHandle(
  92       MojoHandle buffer_handle,
  93       const MojoDuplicateBufferHandleOptions* options,
  94       MojoHandle* new_buffer_handle);
  95   MojoResult MapBuffer(MojoHandle buffer_handle,
  96                        uint64_t offset,
  97                        uint64_t num_bytes,
  98                        void** buffer,
  99                        MojoMapBufferFlags flags);
 100   MojoResult UnmapBuffer(void* buffer);
 101
 102  private:
 103   friend bool internal::ShutdownCheckNoLeaks(Core*);
 104
 105   // Internal implementation of |Wait()| and |WaitMany()|; doesn't do basic
 106   // validation of arguments.
 107   MojoResult WaitManyInternal(const MojoHandle* handles,
 108                               const MojoWaitFlags* flags,
 109                               uint32_t num_handles,
 110                               MojoDeadline deadline);
 111
 112   // ---------------------------------------------------------------------------
 113
 114   // TODO(vtl): |handle_table_lock_| should be a reader-writer lock (if only we
 115   // had them).
 116   base::Lock handle_table_lock_;  // Protects |handle_table_|.
 117   HandleTable handle_table_;
 118
 119   base::Lock mapping_table_lock_;  // Protects |mapping_table_|.
 120   MappingTable mapping_table_;
 121
 122   // ---------------------------------------------------------------------------
 123
 124   DISALLOW_COPY_AND_ASSIGN(Core);
 125 };
 126
 127 }  // namespace system
 128 }  // namespace mojo
 129
 130 #endif  // MOJO_SYSTEM_CORE_H_