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 CONTENT_BROWSER_STREAMS_STREAM_H_ 6 #define CONTENT_BROWSER_STREAMS_STREAM_H_ 7 8 #include "base/basictypes.h" 9 #include "base/memory/ref_counted.h" 10 #include "base/memory/weak_ptr.h" 11 #include "content/browser/byte_stream.h" 12 #include "content/common/content_export.h" 13 #include "url/gurl.h" 14 15 namespace net { 16 class IOBuffer; 17 } 18 19 namespace content { 20 21 class StreamHandle; 22 class StreamHandleImpl; 23 class StreamReadObserver; 24 class StreamRegistry; 25 class StreamWriteObserver; 26 27 // A stream that sends data from an arbitrary source to an internal URL 28 // that can be read by an internal consumer. It will continue to pull from the 29 // original URL as long as there is data available. It can be read from 30 // multiple clients, but only one can be reading at a time. This allows a 31 // reader to consume part of the stream, then pass it along to another client 32 // to continue processing the stream. 33 class CONTENT_EXPORT Stream : public base::RefCountedThreadSafe<Stream> { 34 public: 35 enum StreamState { 36 STREAM_HAS_DATA, 37 STREAM_COMPLETE, 38 STREAM_EMPTY, 39 }; 40 41 // Creates a stream. 42 // 43 // Security origin of Streams is checked in Blink (See BlobRegistry, 44 // BlobURL and SecurityOrigin to understand how it works). There's no security 45 // origin check in Chromium side for now. 46 Stream(StreamRegistry* registry, 47 StreamWriteObserver* write_observer, 48 const GURL& url); 49 50 // Sets the reader of this stream. Returns true on success, or false if there 51 // is already a reader. 52 bool SetReadObserver(StreamReadObserver* observer); 53 54 // Removes the read observer. |observer| must be the current observer. 55 void RemoveReadObserver(StreamReadObserver* observer); 56 57 // Removes the write observer. |observer| must be the current observer. 58 void RemoveWriteObserver(StreamWriteObserver* observer); 59 60 // Adds the data in |buffer| to the stream. Takes ownership of |buffer|. 61 void AddData(scoped_refptr<net::IOBuffer> buffer, size_t size); 62 // Adds data of |size| at |data| to the stream. This method creates a copy 63 // of the data, and then passes it to |writer_|. 64 void AddData(const char* data, size_t size); 65 66 // Notifies this stream that it will not be receiving any more data. 67 void Finalize(); 68 69 // Reads a maximum of |buf_size| from the stream into |buf|. Sets 70 // |*bytes_read| to the number of bytes actually read. 71 // Returns STREAM_HAS_DATA if data was read, STREAM_EMPTY if no data was read, 72 // and STREAM_COMPLETE if the stream is finalized and all data has been read. 73 StreamState ReadRawData(net::IOBuffer* buf, int buf_size, int* bytes_read); 74 75 scoped_ptr<StreamHandle> CreateHandle(const GURL& original_url, 76 const std::string& mime_type); 77 void CloseHandle(); 78 79 // Indicates whether there is space in the buffer to add more data. 80 bool can_add_data() const { return can_add_data_; } 81 82 const GURL& url() const { return url_; } 83 84 private: 85 friend class base::RefCountedThreadSafe<Stream>; 86 87 virtual ~Stream(); 88 89 void OnSpaceAvailable(); 90 void OnDataAvailable(); 91 92 size_t data_bytes_read_; 93 bool can_add_data_; 94 95 GURL url_; 96 97 scoped_refptr<net::IOBuffer> data_; 98 size_t data_length_; 99 100 scoped_ptr<ByteStreamWriter> writer_; 101 scoped_ptr<ByteStreamReader> reader_; 102 103 StreamRegistry* registry_; 104 StreamReadObserver* read_observer_; 105 StreamWriteObserver* write_observer_; 106 107 StreamHandleImpl* stream_handle_; 108 109 base::WeakPtrFactory<Stream> weak_ptr_factory_; 110 DISALLOW_COPY_AND_ASSIGN(Stream); 111 }; 112 113 } // namespace content 114 115 #endif // CONTENT_BROWSER_STREAMS_STREAM_H_ 116
