src/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 <stdint.h>
   9
  10 #include "base/macros.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/synchronization/lock.h"
  14 #include "mojo/public/c/system/buffer.h"
  15 #include "mojo/public/c/system/data_pipe.h"
  16 #include "mojo/public/c/system/message_pipe.h"
  17 #include "mojo/public/c/system/types.h"
  18 #include "mojo/system/handle_table.h"
  19 #include "mojo/system/mapping_table.h"
  20 #include "mojo/system/memory.h"
  21 #include "mojo/system/system_impl_export.h"
  22
  23 namespace mojo {
  24
  25 namespace embedder {
  26 class PlatformSupport;
  27 }
  28
  29 namespace system {
  30
  31 class Dispatcher;
  32 struct HandleSignalsState;
  33
  34 // |Core| is an object that implements the Mojo system calls. All public methods
  35 // are thread-safe.
  36 class MOJO_SYSTEM_IMPL_EXPORT Core {
  37  public:
  38   // ---------------------------------------------------------------------------
  39
  40   // These methods are only to be used by via the embedder API (and internally):
  41   explicit Core(scoped_ptr<embedder::PlatformSupport> platform_support);
  42   virtual ~Core();
  43
  44   // Adds |dispatcher| to the handle table, returning the handle for it. Returns
  45   // |MOJO_HANDLE_INVALID| on failure, namely if the handle table is full.
  46   MojoHandle AddDispatcher(const scoped_refptr<Dispatcher>& dispatcher);
  47
  48   // Looks up the dispatcher for the given handle. Returns null if the handle is
  49   // invalid.
  50   scoped_refptr<Dispatcher> GetDispatcher(MojoHandle handle);
  51
  52   embedder::PlatformSupport* platform_support() const {
  53     return platform_support_.get();
  54   }
  55
  56   // ---------------------------------------------------------------------------
  57
  58   // System calls implementation:
  59   MojoTimeTicks GetTimeTicksNow();
  60   MojoResult Close(MojoHandle handle);
  61   MojoResult Wait(MojoHandle handle,
  62                   MojoHandleSignals signals,
  63                   MojoDeadline deadline,
  64                   UserPointer<MojoHandleSignalsState> signals_state);
  65   MojoResult WaitMany(UserPointer<const MojoHandle> handles,
  66                       UserPointer<const MojoHandleSignals> signals,
  67                       uint32_t num_handles,
  68                       MojoDeadline deadline,
  69                       UserPointer<uint32_t> result_index,
  70                       UserPointer<MojoHandleSignalsState> signals_states);
  71   MojoResult CreateMessagePipe(
  72       UserPointer<const MojoCreateMessagePipeOptions> options,
  73       UserPointer<MojoHandle> message_pipe_handle0,
  74       UserPointer<MojoHandle> message_pipe_handle1);
  75   MojoResult WriteMessage(MojoHandle message_pipe_handle,
  76                           UserPointer<const void> bytes,
  77                           uint32_t num_bytes,
  78                           UserPointer<const MojoHandle> handles,
  79                           uint32_t num_handles,
  80                           MojoWriteMessageFlags flags);
  81   MojoResult ReadMessage(MojoHandle message_pipe_handle,
  82                          UserPointer<void> bytes,
  83                          UserPointer<uint32_t> num_bytes,
  84                          UserPointer<MojoHandle> handles,
  85                          UserPointer<uint32_t> num_handles,
  86                          MojoReadMessageFlags flags);
  87   MojoResult CreateDataPipe(
  88       UserPointer<const MojoCreateDataPipeOptions> options,
  89       UserPointer<MojoHandle> data_pipe_producer_handle,
  90       UserPointer<MojoHandle> data_pipe_consumer_handle);
  91   MojoResult WriteData(MojoHandle data_pipe_producer_handle,
  92                        UserPointer<const void> elements,
  93                        UserPointer<uint32_t> num_bytes,
  94                        MojoWriteDataFlags flags);
  95   MojoResult BeginWriteData(MojoHandle data_pipe_producer_handle,
  96                             UserPointer<void*> buffer,
  97                             UserPointer<uint32_t> buffer_num_bytes,
  98                             MojoWriteDataFlags flags);
  99   MojoResult EndWriteData(MojoHandle data_pipe_producer_handle,
 100                           uint32_t num_bytes_written);
 101   MojoResult ReadData(MojoHandle data_pipe_consumer_handle,
 102                       UserPointer<void> elements,
 103                       UserPointer<uint32_t> num_bytes,
 104                       MojoReadDataFlags flags);
 105   MojoResult BeginReadData(MojoHandle data_pipe_consumer_handle,
 106                            UserPointer<const void*> buffer,
 107                            UserPointer<uint32_t> buffer_num_bytes,
 108                            MojoReadDataFlags flags);
 109   MojoResult EndReadData(MojoHandle data_pipe_consumer_handle,
 110                          uint32_t num_bytes_read);
 111   MojoResult CreateSharedBuffer(
 112       UserPointer<const MojoCreateSharedBufferOptions> options,
 113       uint64_t num_bytes,
 114       UserPointer<MojoHandle> shared_buffer_handle);
 115   MojoResult DuplicateBufferHandle(
 116       MojoHandle buffer_handle,
 117       UserPointer<const MojoDuplicateBufferHandleOptions> options,
 118       UserPointer<MojoHandle> new_buffer_handle);
 119   MojoResult MapBuffer(MojoHandle buffer_handle,
 120                        uint64_t offset,
 121                        uint64_t num_bytes,
 122                        UserPointer<void*> buffer,
 123                        MojoMapBufferFlags flags);
 124   MojoResult UnmapBuffer(UserPointer<void> buffer);
 125
 126  private:
 127   friend bool internal::ShutdownCheckNoLeaks(Core*);
 128
 129   // Internal implementation of |Wait()| and |WaitMany()|; doesn't do basic
 130   // validation of arguments. |*result_index| is only set if the result (whether
 131   // success or failure) applies to a specific handle, so its value should be
 132   // preinitialized to |static_cast<uint32_t>(-1)|.
 133   MojoResult WaitManyInternal(const MojoHandle* handles,
 134                               const MojoHandleSignals* signals,
 135                               uint32_t num_handles,
 136                               MojoDeadline deadline,
 137                               uint32_t* result_index,
 138                               HandleSignalsState* signals_states);
 139
 140   const scoped_ptr<embedder::PlatformSupport> platform_support_;
 141
 142   // TODO(vtl): |handle_table_lock_| should be a reader-writer lock (if only we
 143   // had them).
 144   base::Lock handle_table_lock_;  // Protects |handle_table_|.
 145   HandleTable handle_table_;
 146
 147   base::Lock mapping_table_lock_;  // Protects |mapping_table_|.
 148   MappingTable mapping_table_;
 149
 150   DISALLOW_COPY_AND_ASSIGN(Core);
 151 };
 152
 153 }  // namespace system
 154 }  // namespace mojo
 155
 156 #endif  // MOJO_SYSTEM_CORE_H_