Move mojo edk into mojo/edk

mojo/system/data_pipe.h

-// Copyright 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef MOJO_SYSTEM_DATA_PIPE_H_
-#define MOJO_SYSTEM_DATA_PIPE_H_
-
-#include <stdint.h>
-
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/synchronization/lock.h"
-#include "mojo/public/c/system/data_pipe.h"
-#include "mojo/public/c/system/types.h"
-#include "mojo/system/handle_signals_state.h"
-#include "mojo/system/memory.h"
-#include "mojo/system/system_impl_export.h"
-
-namespace mojo {
-namespace system {
-
-class Waiter;
-class WaiterList;
-
-// |DataPipe| is a base class for secondary objects implementing data pipes,
-// similar to |MessagePipe| (see the explanatory comment in core.cc). It is
-// typically owned by the dispatcher(s) corresponding to the local endpoints.
-// Its subclasses implement the three cases: local producer and consumer, local
-// producer and remote consumer, and remote producer and local consumer. This
-// class is thread-safe.
-class MOJO_SYSTEM_IMPL_EXPORT DataPipe
-    : public base::RefCountedThreadSafe<DataPipe> {
- public:
-  // The default options for |MojoCreateDataPipe()|. (Real uses should obtain
-  // this via |ValidateCreateOptions()| with a null |in_options|; this is
-  // exposed directly for testing convenience.)
-  static const MojoCreateDataPipeOptions kDefaultCreateOptions;
-
-  // Validates and/or sets default options for |MojoCreateDataPipeOptions|. If
-  // non-null, |in_options| must point to a struct of at least
-  // |in_options->struct_size| bytes. |out_options| must point to a (current)
-  // |MojoCreateDataPipeOptions| and will be entirely overwritten on success (it
-  // may be partly overwritten on failure).
-  static MojoResult ValidateCreateOptions(
-      UserPointer<const MojoCreateDataPipeOptions> in_options,
-      MojoCreateDataPipeOptions* out_options);
-
-  // These are called by the producer dispatcher to implement its methods of
-  // corresponding names.
-  void ProducerCancelAllWaiters();
-  void ProducerClose();
-  MojoResult ProducerWriteData(UserPointer<const void> elements,
-                               UserPointer<uint32_t> num_bytes,
-                               bool all_or_none);
-  MojoResult ProducerBeginWriteData(UserPointer<void*> buffer,
-                                    UserPointer<uint32_t> buffer_num_bytes,
-                                    bool all_or_none);
-  MojoResult ProducerEndWriteData(uint32_t num_bytes_written);
-  HandleSignalsState ProducerGetHandleSignalsState();
-  MojoResult ProducerAddWaiter(Waiter* waiter,
-                               MojoHandleSignals signals,
-                               uint32_t context,
-                               HandleSignalsState* signals_state);
-  void ProducerRemoveWaiter(Waiter* waiter, HandleSignalsState* signals_state);
-  bool ProducerIsBusy() const;
-
-  // These are called by the consumer dispatcher to implement its methods of
-  // corresponding names.
-  void ConsumerCancelAllWaiters();
-  void ConsumerClose();
-  // This does not validate its arguments, except to check that |*num_bytes| is
-  // a multiple of |element_num_bytes_|.
-  MojoResult ConsumerReadData(UserPointer<void> elements,
-                              UserPointer<uint32_t> num_bytes,
-                              bool all_or_none);
-  MojoResult ConsumerDiscardData(UserPointer<uint32_t> num_bytes,
-                                 bool all_or_none);
-  MojoResult ConsumerQueryData(UserPointer<uint32_t> num_bytes);
-  MojoResult ConsumerBeginReadData(UserPointer<const void*> buffer,
-                                   UserPointer<uint32_t> buffer_num_bytes,
-                                   bool all_or_none);
-  MojoResult ConsumerEndReadData(uint32_t num_bytes_read);
-  HandleSignalsState ConsumerGetHandleSignalsState();
-  MojoResult ConsumerAddWaiter(Waiter* waiter,
-                               MojoHandleSignals signals,
-                               uint32_t context,
-                               HandleSignalsState* signals_state);
-  void ConsumerRemoveWaiter(Waiter* waiter, HandleSignalsState* signals_state);
-  bool ConsumerIsBusy() const;
-
- protected:
-  DataPipe(bool has_local_producer,
-           bool has_local_consumer,
-           const MojoCreateDataPipeOptions& validated_options);
-
-  friend class base::RefCountedThreadSafe<DataPipe>;
-  virtual ~DataPipe();
-
-  virtual void ProducerCloseImplNoLock() = 0;
-  // |num_bytes.Get()| will be a nonzero multiple of |element_num_bytes_|.
-  virtual MojoResult ProducerWriteDataImplNoLock(
-      UserPointer<const void> elements,
-      UserPointer<uint32_t> num_bytes,
-      uint32_t max_num_bytes_to_write,
-      uint32_t min_num_bytes_to_write) = 0;
-  virtual MojoResult ProducerBeginWriteDataImplNoLock(
-      UserPointer<void*> buffer,
-      UserPointer<uint32_t> buffer_num_bytes,
-      uint32_t min_num_bytes_to_write) = 0;
-  virtual MojoResult ProducerEndWriteDataImplNoLock(
-      uint32_t num_bytes_written) = 0;
-  // Note: A producer should not be writable during a two-phase write.
-  virtual HandleSignalsState ProducerGetHandleSignalsStateImplNoLock()
-      const = 0;
-
-  virtual void ConsumerCloseImplNoLock() = 0;
-  // |*num_bytes| will be a nonzero multiple of |element_num_bytes_|.
-  virtual MojoResult ConsumerReadDataImplNoLock(
-      UserPointer<void> elements,
-      UserPointer<uint32_t> num_bytes,
-      uint32_t max_num_bytes_to_read,
-      uint32_t min_num_bytes_to_read) = 0;
-  virtual MojoResult ConsumerDiscardDataImplNoLock(
-      UserPointer<uint32_t> num_bytes,
-      uint32_t max_num_bytes_to_discard,
-      uint32_t min_num_bytes_to_discard) = 0;
-  // |*num_bytes| will be a nonzero multiple of |element_num_bytes_|.
-  virtual MojoResult ConsumerQueryDataImplNoLock(
-      UserPointer<uint32_t> num_bytes) = 0;
-  virtual MojoResult ConsumerBeginReadDataImplNoLock(
-      UserPointer<const void*> buffer,
-      UserPointer<uint32_t> buffer_num_bytes,
-      uint32_t min_num_bytes_to_read) = 0;
-  virtual MojoResult ConsumerEndReadDataImplNoLock(uint32_t num_bytes_read) = 0;
-  // Note: A consumer should not be writable during a two-phase read.
-  virtual HandleSignalsState ConsumerGetHandleSignalsStateImplNoLock()
-      const = 0;
-
-  // Thread-safe and fast (they don't take the lock):
-  bool may_discard() const { return may_discard_; }
-  size_t element_num_bytes() const { return element_num_bytes_; }
-  size_t capacity_num_bytes() const { return capacity_num_bytes_; }
-
-  // Must be called under lock.
-  bool producer_open_no_lock() const {
-    lock_.AssertAcquired();
-    return producer_open_;
-  }
-  bool consumer_open_no_lock() const {
-    lock_.AssertAcquired();
-    return consumer_open_;
-  }
-  uint32_t producer_two_phase_max_num_bytes_written_no_lock() const {
-    lock_.AssertAcquired();
-    return producer_two_phase_max_num_bytes_written_;
-  }
-  uint32_t consumer_two_phase_max_num_bytes_read_no_lock() const {
-    lock_.AssertAcquired();
-    return consumer_two_phase_max_num_bytes_read_;
-  }
-  void set_producer_two_phase_max_num_bytes_written_no_lock(
-      uint32_t num_bytes) {
-    lock_.AssertAcquired();
-    producer_two_phase_max_num_bytes_written_ = num_bytes;
-  }
-  void set_consumer_two_phase_max_num_bytes_read_no_lock(uint32_t num_bytes) {
-    lock_.AssertAcquired();
-    consumer_two_phase_max_num_bytes_read_ = num_bytes;
-  }
-  bool producer_in_two_phase_write_no_lock() const {
-    lock_.AssertAcquired();
-    return producer_two_phase_max_num_bytes_written_ > 0;
-  }
-  bool consumer_in_two_phase_read_no_lock() const {
-    lock_.AssertAcquired();
-    return consumer_two_phase_max_num_bytes_read_ > 0;
-  }
-
- private:
-  void AwakeProducerWaitersForStateChangeNoLock(
-      const HandleSignalsState& new_producer_state);
-  void AwakeConsumerWaitersForStateChangeNoLock(
-      const HandleSignalsState& new_consumer_state);
-
-  bool has_local_producer_no_lock() const {
-    lock_.AssertAcquired();
-    return !!producer_waiter_list_;
-  }
-  bool has_local_consumer_no_lock() const {
-    lock_.AssertAcquired();
-    return !!consumer_waiter_list_;
-  }
-
-  const bool may_discard_;
-  const size_t element_num_bytes_;
-  const size_t capacity_num_bytes_;
-
-  mutable base::Lock lock_;  // Protects the following members.
-  // *Known* state of producer or consumer.
-  bool producer_open_;
-  bool consumer_open_;
-  // Non-null only if the producer or consumer, respectively, is local.
-  scoped_ptr<WaiterList> producer_waiter_list_;
-  scoped_ptr<WaiterList> consumer_waiter_list_;
-  // These are nonzero if and only if a two-phase write/read is in progress.
-  uint32_t producer_two_phase_max_num_bytes_written_;
-  uint32_t consumer_two_phase_max_num_bytes_read_;
-
-  DISALLOW_COPY_AND_ASSIGN(DataPipe);
-};
-
-}  // namespace system
-}  // namespace mojo
-
-#endif  // MOJO_SYSTEM_DATA_PIPE_H_