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_LOCAL_DATA_PIPE_H_ 6 #define MOJO_SYSTEM_LOCAL_DATA_PIPE_H_ 7 8 #include "base/basictypes.h" 9 #include "base/memory/aligned_memory.h" 10 #include "base/memory/ref_counted.h" 11 #include "base/memory/scoped_ptr.h" 12 #include "mojo/system/data_pipe.h" 13 #include "mojo/system/system_impl_export.h" 14 15 namespace mojo { 16 namespace system { 17 18 // |LocalDataPipe| is a subclass that "implements" |DataPipe| for data pipes 19 // whose producer and consumer are both local. This class is thread-safe (with 20 // protection provided by |DataPipe|'s |lock_|. 21 class MOJO_SYSTEM_IMPL_EXPORT LocalDataPipe : public DataPipe { 22 public: 23 // |validated_options| should be the output of |DataPipe::ValidateOptions()|. 24 // In particular: |struct_size| is ignored (so |validated_options| must be the 25 // current version of the struct) and |capacity_num_bytes| must be nonzero. 26 explicit LocalDataPipe(const MojoCreateDataPipeOptions& validated_options); 27 28 private: 29 friend class base::RefCountedThreadSafe<LocalDataPipe>; 30 virtual ~LocalDataPipe(); 31 32 // |DataPipe| implementation: 33 virtual void ProducerCloseImplNoLock() OVERRIDE; 34 virtual MojoResult ProducerWriteDataImplNoLock(const void* elements, 35 uint32_t* num_bytes, 36 bool all_or_none) OVERRIDE; 37 virtual MojoResult ProducerBeginWriteDataImplNoLock( 38 void** buffer, 39 uint32_t* buffer_num_bytes, 40 bool all_or_none) OVERRIDE; 41 virtual MojoResult ProducerEndWriteDataImplNoLock( 42 uint32_t num_bytes_written) OVERRIDE; 43 virtual HandleSignalsState 44 ProducerGetHandleSignalsStateNoLock() const OVERRIDE; 45 virtual void ConsumerCloseImplNoLock() OVERRIDE; 46 virtual MojoResult ConsumerReadDataImplNoLock(void* elements, 47 uint32_t* num_bytes, 48 bool all_or_none) OVERRIDE; 49 virtual MojoResult ConsumerDiscardDataImplNoLock(uint32_t* num_bytes, 50 bool all_or_none) OVERRIDE; 51 virtual MojoResult ConsumerQueryDataImplNoLock(uint32_t* num_bytes) OVERRIDE; 52 virtual MojoResult ConsumerBeginReadDataImplNoLock(const void** buffer, 53 uint32_t* buffer_num_bytes, 54 bool all_or_none) OVERRIDE; 55 virtual MojoResult ConsumerEndReadDataImplNoLock( 56 uint32_t num_bytes_read) OVERRIDE; 57 virtual HandleSignalsState 58 ConsumerGetHandleSignalsStateNoLock() const OVERRIDE; 59 60 void EnsureBufferNoLock(); 61 void DestroyBufferNoLock(); 62 63 // Get the maximum (single) write/read size right now (in number of elements); 64 // result fits in a |uint32_t|. 65 size_t GetMaxNumBytesToWriteNoLock(); 66 size_t GetMaxNumBytesToReadNoLock(); 67 68 // Marks the given number of bytes as consumed/discarded. |num_bytes| must be 69 // greater than |current_num_bytes_|. 70 void MarkDataAsConsumedNoLock(size_t num_bytes); 71 72 // The members below are protected by |DataPipe|'s |lock_|: 73 scoped_ptr<char, base::AlignedFreeDeleter> buffer_; 74 // Circular buffer. 75 size_t start_index_; 76 size_t current_num_bytes_; 77 78 DISALLOW_COPY_AND_ASSIGN(LocalDataPipe); 79 }; 80 81 } // namespace system 82 } // namespace mojo 83 84 #endif // MOJO_SYSTEM_LOCAL_DATA_PIPE_H_ 85