android_webview/browser/net/input_stream_reader.h

   1 // Copyright (c) 2012 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 ANDROID_WEBVIEW_NATIVE_INPUT_STREAM_READER_H_
   6 #define ANDROID_WEBVIEW_NATIVE_INPUT_STREAM_READER_H_
   7
   8 #include "base/memory/ref_counted.h"
   9
  10 namespace net {
  11 class HttpByteRange;
  12 class IOBuffer;
  13 }
  14
  15 namespace android_webview {
  16
  17 class InputStream;
  18
  19 // Class responsible for reading the InputStream.
  20 class InputStreamReader {
  21  public:
  22   // The constructor is called on the IO thread, not on the worker thread.
  23   InputStreamReader(android_webview::InputStream* stream);
  24   virtual ~InputStreamReader();
  25
  26   // Perform a seek operation on the InputStream associated with this job.
  27   // On successful completion the InputStream would have skipped reading the
  28   // number of bytes equal to the lower range of |byte_range|.
  29   // This method should be called on the |g_worker_thread| thread.
  30   //
  31   // |byte_range| is the range of bytes to be read from |stream|
  32   //
  33   // A negative return value will indicate an error code, a positive value
  34   // will indicate the expected size of the content.
  35   virtual int Seek(const net::HttpByteRange& byte_range);
  36
  37   // Read data from |stream_|.  This method should be called on the
  38   // |g_worker_thread| thread.
  39   //
  40   // A negative return value will indicate an error code, a positive value
  41   // will indicate the expected size of the content.
  42   virtual int ReadRawData(net::IOBuffer* buffer, int buffer_size);
  43
  44  private:
  45   // Verify the requested range against the stream size.
  46   // net::OK is returned on success, the error code otherwise.
  47   int VerifyRequestedRange(net::HttpByteRange* byte_range,
  48                            int* content_size);
  49
  50   // Skip to the first byte of the requested read range.
  51   // net::OK is returned on success, the error code otherwise.
  52   int SkipToRequestedRange(const net::HttpByteRange& byte_range);
  53
  54   android_webview::InputStream* stream_;
  55
  56   DISALLOW_COPY_AND_ASSIGN(InputStreamReader);
  57 };
  58
  59 } // namespace android_webview
  60
  61 #endif //  ANDROID_WEBVIEW_NATIVE_INPUT_STREAM_READER_H_