src/add-ons/translators/shared/StreamBuffer.h

   1 /*
   2  * Copyright 2003-2008, Haiku, Inc. All rights reserved.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Authors :
   6  *              Michael Wilber
   7  *              Jérôme Duval
   8  */
   9
  10 #ifndef STREAM_BUFFER_H
  11 #define STREAM_BUFFER_H
  12
  13 #include <DataIO.h>
  14
  15 #define MIN_BUFFER_SIZE 512
  16
  17 class StreamBuffer {
  18 public:
  19         StreamBuffer(BPositionIO *stream, size_t bufferSize, bool toRead = true);
  20         ~StreamBuffer();
  21
  22         status_t InitCheck();
  23                 // Determines whether the constructor failed or not
  24
  25         ssize_t Read(void *buffer, size_t size);
  26                 // copy nbytes from the stream into pinto
  27
  28         void Write(void *buffer, size_t size);
  29                 // copy nbytes from the stream into pinto
  30
  31         off_t Seek(off_t position, uint32 seekMode);
  32                 // seek the stream to the given position
  33
  34         off_t Position();
  35                 // return the actual position
  36 private:
  37         ssize_t _ReadStream();
  38                 // Load the stream buffer from the stream
  39
  40         BPositionIO *fStream;
  41                 // stream object this object is buffering
  42         uint8 *fBuffer;
  43                 // buffered data from fpStream
  44         size_t fBufferSize;
  45                 // number of bytes of memory allocated for fpBuffer
  46         size_t fLen;
  47                 // number of bytes of actual data in fpBuffer
  48         size_t fPos;
  49                 // current position in the buffer
  50         bool fToRead;
  51                 // whether the stream is to be read.
  52 };
  53
  54 #endif