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// 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_LOCAL_DATA_PIPE_H_
#define MOJO_SYSTEM_LOCAL_DATA_PIPE_H_
#include "base/basictypes.h"
#include "base/memory/aligned_memory.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "mojo/system/data_pipe.h"
#include "mojo/system/system_impl_export.h"
namespace mojo {
namespace system {
// |LocalDataPipe| is a subclass that "implements" |DataPipe| for data pipes
// whose producer and consumer are both local. This class is thread-safe (with
// protection provided by |DataPipe|'s |lock_|.
class MOJO_SYSTEM_IMPL_EXPORT LocalDataPipe : public DataPipe {
public:
// |validated_options| should be the output of |DataPipe::ValidateOptions()|.
// In particular: |struct_size| is ignored (so |validated_options| must be the
// current version of the struct) and |capacity_num_bytes| must be nonzero.
explicit LocalDataPipe(const MojoCreateDataPipeOptions& validated_options);
private:
friend class base::RefCountedThreadSafe<LocalDataPipe>;
virtual ~LocalDataPipe();
// |DataPipe| implementation:
virtual void ProducerCloseImplNoLock() OVERRIDE;
virtual MojoResult ProducerWriteDataImplNoLock(const void* elements,
uint32_t* num_bytes,
bool all_or_none) OVERRIDE;
virtual MojoResult ProducerBeginWriteDataImplNoLock(
void** buffer,
uint32_t* buffer_num_bytes,
bool all_or_none) OVERRIDE;
virtual MojoResult ProducerEndWriteDataImplNoLock(
uint32_t num_bytes_written) OVERRIDE;
virtual HandleSignalsState
ProducerGetHandleSignalsStateNoLock() const OVERRIDE;
virtual void ConsumerCloseImplNoLock() OVERRIDE;
virtual MojoResult ConsumerReadDataImplNoLock(void* elements,
uint32_t* num_bytes,
bool all_or_none) OVERRIDE;
virtual MojoResult ConsumerDiscardDataImplNoLock(uint32_t* num_bytes,
bool all_or_none) OVERRIDE;
virtual MojoResult ConsumerQueryDataImplNoLock(uint32_t* num_bytes) OVERRIDE;
virtual MojoResult ConsumerBeginReadDataImplNoLock(const void** buffer,
uint32_t* buffer_num_bytes,
bool all_or_none) OVERRIDE;
virtual MojoResult ConsumerEndReadDataImplNoLock(
uint32_t num_bytes_read) OVERRIDE;
virtual HandleSignalsState
ConsumerGetHandleSignalsStateNoLock() const OVERRIDE;
void EnsureBufferNoLock();
void DestroyBufferNoLock();
// Get the maximum (single) write/read size right now (in number of elements);
// result fits in a |uint32_t|.
size_t GetMaxNumBytesToWriteNoLock();
size_t GetMaxNumBytesToReadNoLock();
// Marks the given number of bytes as consumed/discarded. |num_bytes| must be
// greater than |current_num_bytes_|.
void MarkDataAsConsumedNoLock(size_t num_bytes);
// The members below are protected by |DataPipe|'s |lock_|:
scoped_ptr<char, base::AlignedFreeDeleter> buffer_;
// Circular buffer.
size_t start_index_;
size_t current_num_bytes_;
DISALLOW_COPY_AND_ASSIGN(LocalDataPipe);
};
} // namespace system
} // namespace mojo
#endif // MOJO_SYSTEM_LOCAL_DATA_PIPE_H_