1 // Copyright (c) 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 NET_SPDY_SPDY_BUFFER_H_ 6 #define NET_SPDY_SPDY_BUFFER_H_ 7 8 #include <cstddef> 9 #include <vector> 10 11 #include "base/basictypes.h" 12 #include "base/callback_forward.h" 13 #include "base/memory/ref_counted.h" 14 #include "base/memory/scoped_ptr.h" 15 #include "net/base/net_export.h" 16 17 namespace net { 18 19 class IOBuffer; 20 class SpdyFrame; 21 22 // SpdyBuffer is a class to hold data read from or to be written to a 23 // SPDY connection. It is similar to a DrainableIOBuffer but is not 24 // ref-counted and will include a way to get notified when Consume() 25 // is called. 26 // 27 // NOTE(akalin): This explicitly does not inherit from IOBuffer to 28 // avoid the needless ref-counting and to avoid working around the 29 // fact that IOBuffer member functions are not virtual. 30 class NET_EXPORT_PRIVATE SpdyBuffer { 31 public: 32 // The source of a call to a ConsumeCallback. 33 enum ConsumeSource { 34 // Called via a call to Consume(). 35 CONSUME, 36 // Called via the SpdyBuffer being destroyed. 37 DISCARD 38 }; 39 40 // A Callback that gets called when bytes are consumed with the 41 // (non-zero) number of bytes consumed and the source of the 42 // consume. May be called any number of times with CONSUME as the 43 // source followed by at most one call with DISCARD as the 44 // source. The sum of the number of bytes consumed equals the total 45 // size of the buffer. 46 typedef base::Callback<void(size_t, ConsumeSource)> ConsumeCallback; 47 48 // Construct with the data in the given frame. Assumes that data is 49 // owned by |frame| or outlives it. 50 explicit SpdyBuffer(scoped_ptr<SpdyFrame> frame); 51 52 // Construct with a copy of the given raw data. |data| must be 53 // non-NULL and |size| must be non-zero. 54 SpdyBuffer(const char* data, size_t size); 55 56 // If there are bytes remaining in the buffer, triggers a call to 57 // any consume callbacks with a DISCARD source. 58 ~SpdyBuffer(); 59 60 // Returns the remaining (unconsumed) data. 61 const char* GetRemainingData() const; 62 63 // Returns the number of remaining (unconsumed) bytes. 64 size_t GetRemainingSize() const; 65 66 // Add a callback to be called when bytes are consumed. The 67 // ConsumeCallback should not do anything complicated; ideally it 68 // should only update a counter. In particular, it must *not* cause 69 // the SpdyBuffer itself to be destroyed. 70 void AddConsumeCallback(const ConsumeCallback& consume_callback); 71 72 // Consume the given number of bytes, which must be positive but not 73 // greater than GetRemainingSize(). 74 void Consume(size_t consume_size); 75 76 // Returns an IOBuffer pointing to the data starting at 77 // GetRemainingData(). Use with care; the returned IOBuffer is not 78 // updated when Consume() is called. However, it may still be used 79 // past the lifetime of this object. 80 // 81 // This is used with Socket::Write(), which takes an IOBuffer* that 82 // may be written to even after the socket itself is destroyed. (See 83 // http://crbug.com/249725 .) 84 IOBuffer* GetIOBufferForRemainingData(); 85 86 private: 87 void ConsumeHelper(size_t consume_size, ConsumeSource consume_source); 88 89 // Ref-count the passed-in SpdyFrame to support the semantics of 90 // |GetIOBufferForRemainingData()|. 91 typedef base::RefCountedData<scoped_ptr<SpdyFrame> > SharedFrame; 92 93 class SharedFrameIOBuffer; 94 95 const scoped_refptr<SharedFrame> shared_frame_; 96 std::vector<ConsumeCallback> consume_callbacks_; 97 size_t offset_; 98 99 DISALLOW_COPY_AND_ASSIGN(SpdyBuffer); 100 }; 101 102 } // namespace net 103 104 #endif // NET_SPDY_SPDY_BUFFER_H_ 105