HTTPStream.h

00001 
00002 /*
00003 Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
00004  
00005 Permission is hereby granted, free of charge, to any person obtaining a copy
00006 of this software and associated documentation files (the "Software"), to deal
00007 in the Software without restriction, including without limitation the rights
00008 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00009 copies of the Software, and to permit persons to whom the Software is
00010 furnished to do so, subject to the following conditions:
00011  
00012 The above copyright notice and this permission notice shall be included in
00013 all copies or substantial portions of the Software.
00014  
00015 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00016 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00017 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00018 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00019 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00020 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00021 THE SOFTWARE.
00022 */
00023 
00024 #ifndef HTTP_STREAM_H
00025 #define HTTP_STREAM_H
00026 
00027 #include "../HTTPData.h"
00028 #include "mbed.h"
00029 
00030 /** \file
00031 HTTP Stream data source/sink header file
00032 */
00033 
00034 typedef uint8_t byte;
00035 
00036 ///HTTP Client Streaming tool
00037 /**
00038 This class allows you to stream data from the web using a persisting HTTP connection.
00039 To use it properly you must use a non-blocking HTTPClient method.
00040 */
00041 class HTTPStream : public HTTPData //Streaming buf
00042 {
00043 public:
00044   ///Instantiates the object
00045   HTTPStream();
00046   virtual ~HTTPStream();
00047   
00048   ///Starts to read into buffer
00049   /**
00050   Passes a buffer of address @a buf and size @a size to the instance.
00051   When it receives data it will be stored in this buffer.
00052   When the buffer is full it throttles the client until this function is called again.
00053   */
00054   void readNext(byte* buf, int size);
00055   
00056   ///Returns whether there is data available to read
00057   bool readable();
00058   
00059   ///Returns the actual length of the payload written in the buffer
00060   int readLen();
00061   
00062   virtual void clear();
00063       
00064 protected:
00065   virtual int read(char* buf, int len);
00066   virtual int write(const char* buf, int len);
00067   
00068   virtual string getDataType(); //Internet media type for Content-Type header
00069   virtual void setDataType(const string& type); //Internet media type from Content-Type header
00070 
00071   virtual bool getIsChunked(); //For Transfer-Encoding header
00072   virtual void setIsChunked(bool chunked); //From Transfer-Encoding header
00073   
00074   virtual int getDataLen(); //For Content-Length header
00075   virtual void setDataLen(int len); //From Content-Length header, or if the transfer is chunked, next chunk length
00076   
00077 private:
00078   byte* m_buf;
00079   int m_size; //Capacity
00080   int m_len; //Length
00081 };
00082 
00083 #endif