]> git.saurik.com Git - wxWidgets.git/blobdiff - src/common/stream.cpp
First set of changes toward wxBase compliance :-)
[wxWidgets.git] / src / common / stream.cpp
index b438c2b386b4e525bdd756c200d50a0ab6e6f76a..310f1ee7e09eb77b4353f57a6611348a9baa51e5 100644 (file)
 #pragma implementation "stream.h"
 #endif
 
-#include "wx/object.h"
-#include "wx/stream.h"
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+  #pragma hdrstop
+#endif
 
-#if !USE_SHARED_LIBRARY
-IMPLEMENT_ABSTRACT_CLASS(wxInputStream, wxObject)
-IMPLEMENT_ABSTRACT_CLASS(wxOutputStream, wxObject)
-IMPLEMENT_ABSTRACT_CLASS2(wxStream, wxInputStream, wxOutputStream)
-IMPLEMENT_CLASS(wxFilterInputStream, wxInputStream)
+#ifndef WX_PRECOMP
+  #include "wx/defs.h"
 #endif
 
+#if wxUSE_STREAMS
+
+#include <ctype.h>
+#include "wx/stream.h"
+#include "wx/datstrm.h"
+#include "wx/objstrm.h"
+
+#define BUF_TEMP_SIZE 10000
+
+// ----------------------------------------------------------------------------
+// wxStreamBuffer
+// ----------------------------------------------------------------------------
+
+#define CHECK_ERROR(err) \
+   if (m_stream->m_lasterror == wxStream_NOERROR) \
+     m_stream->m_lasterror = err
+
+wxStreamBuffer::wxStreamBuffer(wxStreamBase& stream, BufMode mode)
+  : m_buffer_start(NULL), m_buffer_end(NULL), m_buffer_pos(NULL),
+    m_buffer_size(0), m_fixed(TRUE), m_flushable(TRUE), m_stream(&stream),
+    m_mode(mode), m_destroybuf(FALSE), m_destroystream(FALSE)
+{
+}
+
+wxStreamBuffer::wxStreamBuffer(BufMode mode)
+  : m_buffer_start(NULL), m_buffer_end(NULL), m_buffer_pos(NULL),
+    m_buffer_size(0), m_fixed(TRUE), m_flushable(FALSE), m_stream(NULL),
+    m_mode(mode), m_destroybuf(FALSE), m_destroystream(TRUE)
+{
+  m_stream = new wxStreamBase();
+}
+
+wxStreamBuffer::wxStreamBuffer(const wxStreamBuffer& buffer)
+{
+  m_buffer_start = buffer.m_buffer_start;
+  m_buffer_end = buffer.m_buffer_end;
+  m_buffer_pos = buffer.m_buffer_pos;
+  m_buffer_size = buffer.m_buffer_size;
+  m_fixed = buffer.m_fixed;
+  m_flushable = buffer.m_flushable;
+  m_stream = buffer.m_stream;
+  m_mode = buffer.m_mode;
+  m_destroybuf = FALSE;
+  m_destroystream = FALSE;
+}
+
+wxStreamBuffer::~wxStreamBuffer()
+{
+  if (m_destroybuf)
+    wxDELETEA(m_buffer_start);
+  if (m_destroystream)
+    delete m_stream;
+}
+
+void wxStreamBuffer::SetBufferIO(char *buffer_start, char *buffer_end)
+{
+  if (m_destroybuf)
+    wxDELETEA(m_buffer_start);
+  m_buffer_start = buffer_start;
+  m_buffer_end   = buffer_end;
+
+  m_buffer_size = m_buffer_end-m_buffer_start;
+  m_destroybuf = FALSE;
+  ResetBuffer();
+}
+
+void wxStreamBuffer::SetBufferIO(size_t bufsize)
+{
+  char *b_start;
+
+  if (m_destroybuf)
+    wxDELETEA(m_buffer_start);
+
+  if (!bufsize) {
+    m_buffer_start = (char*)NULL;
+    m_buffer_end = (char*)NULL;
+    m_buffer_pos = (char*)NULL;
+    m_buffer_size = 0;
+    return;
+  }
+
+  b_start = new char[bufsize];
+  SetBufferIO(b_start, b_start + bufsize);
+  m_destroybuf = TRUE;
+}
+
+void wxStreamBuffer::ResetBuffer()
+{
+  m_stream->m_lasterror = wxStream_NOERROR;
+  m_stream->m_lastcount = 0;
+  if (m_mode == read && m_flushable)
+    m_buffer_pos = m_buffer_end;
+  else
+    m_buffer_pos = m_buffer_start;
+}
+
+bool wxStreamBuffer::FillBuffer()
+{
+  size_t count;
+
+  count = m_stream->OnSysRead(m_buffer_start, m_buffer_size);
+  m_buffer_end = m_buffer_start+count;
+  m_buffer_pos = m_buffer_start;
+
+  if (count == 0)
+    return FALSE;
+  return TRUE;
+}
+
+bool wxStreamBuffer::FlushBuffer()
+{
+  size_t count, current;
+
+  if (m_buffer_pos == m_buffer_start || !m_flushable)
+    return FALSE;
+
+  current = m_buffer_pos-m_buffer_start;
+  count = m_stream->OnSysWrite(m_buffer_start, current);
+  if (count != current)
+    return FALSE;
+  m_buffer_pos = m_buffer_start;
+
+  return TRUE;
+}
+
+void wxStreamBuffer::GetFromBuffer(void *buffer, size_t size)
+{
+  size_t s_toget = m_buffer_end-m_buffer_pos;
+
+  if (size < s_toget)
+    s_toget = size;
+
+  memcpy(buffer, m_buffer_pos, s_toget);
+  m_buffer_pos += s_toget;
+}
+
+void wxStreamBuffer::PutToBuffer(const void *buffer, size_t size)
+{
+  size_t s_toput = m_buffer_end-m_buffer_pos;
+
+  if (s_toput < size && !m_fixed) {
+    if (!m_buffer_start)
+      SetBufferIO(size);
+    else {
+      size_t delta = m_buffer_pos-m_buffer_start;
+
+      m_buffer_start = (char *)realloc(m_buffer_start, m_buffer_size+size);
+      m_buffer_pos   = m_buffer_start + delta;
+      // I round a bit
+      m_buffer_size += size;
+      m_buffer_end   = m_buffer_start+m_buffer_size;
+    }
+    s_toput = size;
+  }
+  if (s_toput > size)
+    s_toput = size;
+  memcpy(m_buffer_pos, buffer, s_toput);
+  m_buffer_pos += s_toput;
+}
+
+void wxStreamBuffer::PutChar(char c)
+{
+  wxASSERT(m_stream != NULL);
+
+  if (!m_buffer_size) {
+    m_stream->OnSysWrite(&c, 1);
+    return;
+  }
+
+  if (GetDataLeft() == 0 && !FlushBuffer()) {
+    CHECK_ERROR(wxStream_WRITE_ERR);
+    return;
+  }
+
+  PutToBuffer(&c, 1);
+  m_stream->m_lastcount = 1;
+}
+
+char wxStreamBuffer::Peek()
+{
+  char c;
+
+  wxASSERT(m_stream != NULL && m_buffer_size != 0);
+
+  if (!GetDataLeft()) {
+    CHECK_ERROR(wxStream_READ_ERR);
+    return 0;
+  }
+
+  GetFromBuffer(&c, 1);
+  m_buffer_pos--;
+
+  return c;
+}
+
+char wxStreamBuffer::GetChar()
+{
+  char c;
+
+  wxASSERT(m_stream != NULL);
+
+  if (!m_buffer_size) {
+    m_stream->OnSysRead(&c, 1);
+    return c;
+  }
+
+  if (!GetDataLeft()) {
+    CHECK_ERROR(wxStream_READ_ERR);
+    return 0;
+  }
+
+  GetFromBuffer(&c, 1);
+
+  m_stream->m_lastcount = 1;
+  return c;
+}
+
+size_t wxStreamBuffer::Read(void *buffer, size_t size)
+{
+  wxASSERT(m_stream != NULL);
+
+  if (m_mode == write)
+    return 0;
+
+  // ------------------
+  // Buffering disabled
+  // ------------------
+
+  m_stream->m_lasterror = wxStream_NOERROR;
+  if (!m_buffer_size)
+    return (m_stream->m_lastcount += m_stream->OnSysRead(buffer, size));
+
+  // -----------------
+  // Buffering enabled
+  // -----------------
+  size_t buf_left, orig_size = size;
+
+  while (size > 0) {
+    buf_left = GetDataLeft();
+
+    // First case: the requested buffer is larger than the stream buffer,
+    //             we split it.
+    if (size > buf_left) {
+      GetFromBuffer(buffer, buf_left);
+      size  -= buf_left;
+      buffer = (char *)buffer + buf_left; // ANSI C++ violation.
+
+      if (!FillBuffer()) {
+        CHECK_ERROR(wxStream_EOF);
+        return (m_stream->m_lastcount = orig_size-size);
+      }
+    } else {
+
+      // Second case: we just copy from the stream buffer.
+      GetFromBuffer(buffer, size);
+      break;
+    }
+  }
+  return (m_stream->m_lastcount += orig_size);
+}
+
+size_t wxStreamBuffer::Read(wxStreamBuffer *s_buf)
+{
+  char buf[BUF_TEMP_SIZE];
+  size_t s = 0, bytes_read = BUF_TEMP_SIZE;
+
+  if (m_mode == write)
+    return 0;
+
+  while (bytes_read != 0) {
+    bytes_read = Read(buf, bytes_read);
+    bytes_read = s_buf->Write(buf, bytes_read);
+    s += bytes_read;
+  }
+  return s;
+}
+
+size_t wxStreamBuffer::Write(const void *buffer, size_t size)
+{
+  wxASSERT(m_stream != NULL);
+
+  if (m_mode == read)
+    return 0;
+
+  // ------------------
+  // Buffering disabled
+  // ------------------
+
+  m_stream->m_lasterror = wxStream_NOERROR;
+  if (!m_buffer_size && m_fixed)
+    return (m_stream->m_lastcount = m_stream->OnSysWrite(buffer, size));
+
+  // ------------------
+  // Buffering enabled
+  // ------------------
+
+  size_t buf_left, orig_size = size;
+
+  while (size > 0) {
+    buf_left = m_buffer_end - m_buffer_pos;
+
+    // First case: the buffer to write is larger than the stream buffer,
+    //             we split it
+    // NB: If stream buffer isn't fixed (as for wxMemoryOutputStream),
+    // we always go to the second case.
+    if (size > buf_left && m_fixed) {
+      PutToBuffer(buffer, buf_left);
+      size -= buf_left;
+      buffer = (char *)buffer + buf_left; // ANSI C++ violation.
+
+      if (!FlushBuffer()) {
+       CHECK_ERROR(wxStream_WRITE_ERR);
+        return (m_stream->m_lastcount = orig_size-size);
+      }
+
+      m_buffer_pos = m_buffer_start;
+
+    } else {
+
+      // Second case: just copy it in the stream buffer.
+      PutToBuffer(buffer, size);
+      break;
+    }
+  }
+  return (m_stream->m_lastcount = orig_size);
+}
+
+size_t wxStreamBuffer::Write(wxStreamBuffer *sbuf)
+{
+  char buf[BUF_TEMP_SIZE];
+  size_t s = 0, bytes_count = BUF_TEMP_SIZE, b_count2;
+  wxInputStream *in_stream;
+
+  if (m_mode == read)
+    return 0;
+
+  in_stream = (wxInputStream *)sbuf->Stream();
+
+  while (bytes_count == BUF_TEMP_SIZE) {
+    b_count2 = sbuf->Read(buf, bytes_count);
+    bytes_count = Write(buf, b_count2);
+    if (b_count2 > bytes_count)
+      in_stream->Ungetch(buf+bytes_count, b_count2-bytes_count);
+    s += bytes_count;
+  }
+  return s;
+}
+
+off_t wxStreamBuffer::Seek(off_t pos, wxSeekMode mode)
+{
+  off_t ret_off, diff, last_access;
+
+  last_access = GetLastAccess();
+
+  if (!m_flushable) {
+    switch (mode) {
+      case wxFromStart:   diff = pos;                     break;
+      case wxFromCurrent: diff = pos + GetIntPosition();  break;
+      case wxFromEnd:     diff = pos + last_access;       break;
+      default: return wxInvalidOffset;
+    }
+    if (diff < 0 || diff > last_access)
+      return wxInvalidOffset;
+    SetIntPosition(diff);
+    return diff;
+  }
+
+  switch (mode) {
+  case wxFromStart: {
+    // We'll try to compute an internal position later ...
+    ret_off = m_stream->OnSysSeek(pos, wxFromStart);
+    ResetBuffer();
+    return ret_off;
+  }
+  case wxFromCurrent: {
+    diff = pos + GetIntPosition();
+
+    if ( (diff > last_access) || (diff < 0) ) {
+      // We must take into account the fact that we have read something
+      // previously.
+      ret_off = m_stream->OnSysSeek(diff-last_access, wxFromCurrent);
+      ResetBuffer();
+      return ret_off;
+    } else {
+      SetIntPosition(diff);
+      return pos;
+    }
+  }
+  case wxFromEnd:
+    // Hard to compute: always seek to the requested position.
+    ret_off = m_stream->OnSysSeek(pos, wxFromEnd);
+    ResetBuffer();
+    return ret_off;
+  }
+  return wxInvalidOffset;
+}
+
+off_t wxStreamBuffer::Tell() const
+{
+    off_t pos = m_stream->OnSysTell();
+    if (pos == wxInvalidOffset)
+        return wxInvalidOffset;
+
+    pos += GetIntPosition();
+
+    if (m_mode == read && m_flushable)
+        pos -= GetLastAccess();
+
+    return pos;
+}
+
+size_t wxStreamBuffer::GetDataLeft()
+{
+    /* Why is this done? RR. */
+    if (m_buffer_end == m_buffer_pos && m_flushable)
+        FillBuffer();
+
+    return m_buffer_end-m_buffer_pos;
+}
+
+// ----------------------------------------------------------------------------
+// wxStreamBase
+// ----------------------------------------------------------------------------
+
+wxStreamBase::wxStreamBase()
+{
+    m_lasterror = wxStream_NOERROR;
+    m_lastcount = 0;
+}
+
+wxStreamBase::~wxStreamBase()
+{
+}
+
+size_t wxStreamBase::OnSysRead(void *WXUNUSED(buffer), size_t WXUNUSED(size))
+{
+    return 0;
+}
+
+size_t wxStreamBase::OnSysWrite(const void *WXUNUSED(buffer), size_t WXUNUSED(bufsize))
+{
+    return 0;
+}
+
+off_t wxStreamBase::OnSysSeek(off_t WXUNUSED(seek), wxSeekMode WXUNUSED(mode))
+{
+    return wxInvalidOffset;
+}
+
+off_t wxStreamBase::OnSysTell() const
+{
+    return wxInvalidOffset;
+}
+
+// ----------------------------------------------------------------------------
+// wxInputStream
+// ----------------------------------------------------------------------------
+
 wxInputStream::wxInputStream()
-  : wxObject()
+  : wxStreamBase(),
+    m_wback(NULL), m_wbacksize(0), m_wbackcur(0)
 {
 }
 
 wxInputStream::~wxInputStream()
 {
+  if (m_wback)
+    free(m_wback);
 }
 
-#define BUF_TEMP_SIZE 10000
+bool wxInputStream::Eof() const
+{
+    wxInputStream *self = (wxInputStream *)this;    // const_cast
+
+    char c;
+    self->Read(&c, 1);
+    if ( GetLastError() == wxSTREAM_EOF )
+    {
+        return TRUE;
+    }
+
+    self->Ungetch(c);
+
+    return FALSE;
+}
+
+char *wxInputStream::AllocSpaceWBack(size_t needed_size)
+{
+    /* get number of bytes left from previous wback buffer */
+    size_t toget = m_wbacksize - m_wbackcur;
+
+    /* allocate a buffer large enough to hold prev + new data */
+    char *temp_b = (char *) malloc(needed_size + toget);
+
+    if (!temp_b)
+        return NULL;
+
+    /* copy previous data (and free old buffer) if needed */
+    if (m_wback)
+    {
+        memmove(temp_b + needed_size, m_wback + m_wbackcur, toget);
+        free(m_wback);
+    }
+
+    /* done */
+    m_wback = temp_b;
+    m_wbackcur = 0;
+    m_wbacksize = needed_size + toget;
+
+    return (char *) m_wback;
+}
+
+size_t wxInputStream::GetWBack(char *buf, size_t bsize)
+{
+    size_t s_toget = m_wbacksize-m_wbackcur;
+
+    if (!m_wback)
+        return 0;
+
+    if (bsize < s_toget)
+       s_toget = bsize;
+
+    memcpy(buf, (m_wback+m_wbackcur), s_toget);
+
+    m_wbackcur += s_toget;
+    if (m_wbackcur == m_wbacksize)
+    {
+        free(m_wback);
+        m_wback = (char *)NULL;
+        m_wbacksize = 0;
+        m_wbackcur = 0;
+    }
+
+    return s_toget;
+}
+
+size_t wxInputStream::Ungetch(const void *buf, size_t bufsize)
+{
+    char *ptrback = AllocSpaceWBack(bufsize);
+    if (!ptrback)
+        return 0;
+
+    memcpy(ptrback, buf, bufsize);
+    return bufsize;
+}
+
+bool wxInputStream::Ungetch(char c)
+{
+    char * ptrback = AllocSpaceWBack(1);
+    if (!ptrback)
+        return FALSE;
+
+    *ptrback = c;
+    return TRUE;
+}
+
+char wxInputStream::GetC()
+{
+    char c;
+    Read(&c, 1);
+    return c;
+}
+
+wxInputStream& wxInputStream::Read(void *buffer, size_t size)
+{
+    char *buf = (char *)buffer;
+
+    size_t retsize = GetWBack(buf, size);
+    if (retsize == size)
+    {
+        m_lastcount = size;
+        m_lasterror = wxStream_NOERROR;
+        return *this;
+    }
+    size -= retsize;
+    buf  += retsize;
+
+    m_lastcount = OnSysRead(buf, size) + retsize;
+    return *this;
+}
+
+char wxInputStream::Peek()
+{
+    char c;
+    Read(&c, 1);
+    if (m_lasterror == wxStream_NOERROR)
+    {
+        Ungetch(c);
+        return c;
+    }
+
+    return 0;
+}
 
 wxInputStream& wxInputStream::Read(wxOutputStream& stream_out)
 {
-  char buf[BUF_TEMP_SIZE]; 
-  size_t bytes_read = BUF_TEMP_SIZE;
+    char buf[BUF_TEMP_SIZE];
+    size_t bytes_read = BUF_TEMP_SIZE;
 
-  while (bytes_read == BUF_TEMP_SIZE && !stream_out.Bad()) {
-    bytes_read = Read(buf, bytes_read).LastRead();
+    while (bytes_read == BUF_TEMP_SIZE)
+    {
+        bytes_read = Read(buf, bytes_read).LastRead();
+        bytes_read = stream_out.Write(buf, bytes_read).LastWrite();
+    }
+    return *this;
+}
 
-    stream_out.Write(buf, bytes_read);
-  }
-  return *this;
+off_t wxInputStream::SeekI(off_t pos, wxSeekMode mode)
+{
+    /* Should be check and improve, just to remove a slight bug !
+       I don't know whether it should be put as well in wxFileInputStream::OnSysSeek ? */
+    if (m_lasterror==wxSTREAM_EOF)
+        m_lasterror=wxSTREAM_NOERROR;
+
+    /* A call to SeekI() will automatically invalidate any previous call
+       to Ungetch(), otherwise it would be possible to SeekI() to one
+       one position, unread some bytes there, SeekI() to another position
+       and the data would be corrupted.
+
+       GRG: Could add code here to try to navigate within the wback
+       buffer if possible, but is it really needed? It would only work
+       when seeking in wxFromCurrent mode, else it would invalidate
+       anyway...
+     */
+    if (m_wback)
+    {
+        free(m_wback);
+        m_wback = (char*) NULL;
+        m_wbacksize = 0;
+        m_wbackcur = 0;
+    }
+
+    return OnSysSeek(pos, mode);
+}
+
+off_t wxInputStream::TellI() const
+{
+    /* GRG: Changed to make it compatible with the wback buffer */
+    off_t pos = OnSysTell();
+
+    if (pos != wxInvalidOffset)
+        pos -= (m_wbacksize - m_wbackcur);
+
+    return pos;
 }
 
+// --------------------
+// Overloaded operators
+// --------------------
+
+#if wxUSE_SERIAL
+wxInputStream& wxInputStream::operator>>(wxObject *& obj)
+{
+    wxObjectInputStream obj_s(*this);
+    obj = obj_s.LoadObject();
+    return *this;
+}
+#endif
+
+
+// ----------------------------------------------------------------------------
+// wxOutputStream
+// ----------------------------------------------------------------------------
 wxOutputStream::wxOutputStream()
-  : wxObject()
+  : wxStreamBase()
 {
 }
 
@@ -56,28 +696,270 @@ wxOutputStream::~wxOutputStream()
 {
 }
 
+void wxOutputStream::PutC(char c)
+{
+    Write((void *) &c, 1);
+}
+
+wxOutputStream& wxOutputStream::Write(const void *buffer, size_t size)
+{
+    m_lastcount = OnSysWrite(buffer, size);
+    return *this;
+}
+
 wxOutputStream& wxOutputStream::Write(wxInputStream& stream_in)
 {
-   stream_in.Read(*this);
-   return *this;
+    stream_in.Read(*this);
+    return *this;
+}
+
+off_t wxOutputStream::TellO() const
+{
+    return OnSysTell();
+}
+
+off_t wxOutputStream::SeekO(off_t pos, wxSeekMode mode)
+{
+    return OnSysSeek(pos, mode);
+}
+
+void wxOutputStream::Sync()
+{
+}
+
+#if wxUSE_SERIAL
+wxOutputStream& wxOutputStream::operator<<(wxObject& obj)
+{
+    wxObjectOutputStream obj_s(*this);
+    obj_s.SaveObject(obj);
+    return *this;
+}
+#endif
+
+// ----------------------------------------------------------------------------
+// wxCountingOutputStream
+// ----------------------------------------------------------------------------
+
+wxCountingOutputStream::wxCountingOutputStream ()
+  : wxOutputStream()
+{
+     m_currentPos = 0;
+}
+
+size_t wxCountingOutputStream::GetSize() const
+{
+    return m_lastcount;
+}
+
+size_t wxCountingOutputStream::OnSysWrite(const void *WXUNUSED(buffer), size_t size)
+{
+    m_currentPos += size;
+    if (m_currentPos > m_lastcount) m_lastcount = m_currentPos;
+    return m_currentPos;
+}
+
+off_t wxCountingOutputStream::OnSysSeek(off_t pos, wxSeekMode mode)
+{
+    if (mode == wxFromStart)
+        m_currentPos = pos;
+    if (mode == wxFromEnd)
+        m_currentPos = m_lastcount + pos;
+    else
+        m_currentPos += pos;
+
+    if (m_currentPos > m_lastcount) m_lastcount = m_currentPos;
+
+    return m_currentPos;
+}
+
+off_t wxCountingOutputStream::OnSysTell() const
+{
+    return m_currentPos;
+}
+
+// ----------------------------------------------------------------------------
+// wxFilterInputStream
+// ----------------------------------------------------------------------------
+
+wxFilterInputStream::wxFilterInputStream()
+  : wxInputStream()
+{
 }
 
 wxFilterInputStream::wxFilterInputStream(wxInputStream& stream)
   : wxInputStream()
 {
-  m_parent_i_stream = &stream;
+    m_parent_i_stream = &stream;
 }
 
 wxFilterInputStream::~wxFilterInputStream()
 {
 }
 
+// ----------------------------------------------------------------------------
+// wxFilterOutputStream
+// ----------------------------------------------------------------------------
+wxFilterOutputStream::wxFilterOutputStream()
+  : wxOutputStream()
+{
+}
+
 wxFilterOutputStream::wxFilterOutputStream(wxOutputStream& stream)
   : wxOutputStream()
 {
-  m_parent_o_stream = &stream;
+    m_parent_o_stream = &stream;
 }
 
 wxFilterOutputStream::~wxFilterOutputStream()
 {
 }
+
+// ----------------------------------------------------------------------------
+// wxBufferedInputStream
+// ----------------------------------------------------------------------------
+wxBufferedInputStream::wxBufferedInputStream(wxInputStream& s)
+  : wxFilterInputStream(s)
+{
+    m_i_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::read);
+    m_i_streambuf->SetBufferIO(1024);
+}
+
+wxBufferedInputStream::~wxBufferedInputStream()
+{
+    off_t unused_bytes=m_i_streambuf->GetBufferPos()-m_i_streambuf->GetBufferEnd();
+    m_parent_i_stream->SeekI(unused_bytes,wxFromCurrent);
+
+    delete m_i_streambuf;
+}
+
+char wxBufferedInputStream::Peek()
+{
+    return m_i_streambuf->Peek();
+}
+
+wxInputStream& wxBufferedInputStream::Read(void *buffer, size_t size)
+{
+    size_t retsize;
+    char *buf = (char *)buffer;
+
+    retsize = GetWBack(buf, size);
+    m_lastcount = retsize;
+    if (retsize == size)
+    {
+        m_lasterror = wxStream_NOERROR;
+        return *this;
+    }
+    size -= retsize;
+    buf  += retsize;
+
+    m_i_streambuf->Read(buf, size);
+
+    return *this;
+}
+
+off_t wxBufferedInputStream::SeekI(off_t pos, wxSeekMode mode)
+{
+    return m_i_streambuf->Seek(pos, mode);
+}
+
+off_t wxBufferedInputStream::TellI() const
+{
+    return m_i_streambuf->Tell();
+}
+
+size_t wxBufferedInputStream::OnSysRead(void *buffer, size_t bufsize)
+{
+    return m_parent_i_stream->Read(buffer, bufsize).LastRead();
+}
+
+off_t wxBufferedInputStream::OnSysSeek(off_t seek, wxSeekMode mode)
+{
+    return m_parent_i_stream->SeekI(seek, mode);
+}
+
+off_t wxBufferedInputStream::OnSysTell() const
+{
+    return m_parent_i_stream->TellI();
+}
+
+
+// ----------------------------------------------------------------------------
+// wxBufferedOutputStream
+// ----------------------------------------------------------------------------
+
+wxBufferedOutputStream::wxBufferedOutputStream(wxOutputStream& s)
+  : wxFilterOutputStream(s)
+{
+    m_o_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::write);
+    m_o_streambuf->SetBufferIO(1024);
+}
+
+wxBufferedOutputStream::~wxBufferedOutputStream()
+{
+    Sync();
+    delete m_o_streambuf;
+}
+
+wxOutputStream& wxBufferedOutputStream::Write(const void *buffer, size_t size)
+{
+    m_lastcount = 0;
+    m_o_streambuf->Write(buffer, size);
+    return *this;
+}
+
+off_t wxBufferedOutputStream::SeekO(off_t pos, wxSeekMode mode)
+{
+    Sync();
+    return m_o_streambuf->Seek(pos, mode);
+}
+
+off_t wxBufferedOutputStream::TellO() const
+{
+    return m_o_streambuf->Tell();
+}
+
+void wxBufferedOutputStream::Sync()
+{
+    m_o_streambuf->FlushBuffer();
+    m_parent_o_stream->Sync();
+}
+
+size_t wxBufferedOutputStream::OnSysWrite(const void *buffer, size_t bufsize)
+{
+    return m_parent_o_stream->Write(buffer, bufsize).LastWrite();
+}
+
+off_t wxBufferedOutputStream::OnSysSeek(off_t seek, wxSeekMode mode)
+{
+    return m_parent_o_stream->SeekO(seek, mode);
+}
+
+off_t wxBufferedOutputStream::OnSysTell() const
+{
+    return m_parent_o_stream->TellO();
+}
+
+size_t wxBufferedOutputStream::GetSize() const
+{
+   return m_parent_o_stream->GetSize() + m_o_streambuf->GetIntPosition();
+}
+
+// ----------------------------------------------------------------------------
+// Some IOManip function
+// ----------------------------------------------------------------------------
+
+wxOutputStream& wxEndL(wxOutputStream& stream)
+{
+#ifdef __MSW__
+  return stream.Write("\r\n", 2);
+#else
+#ifdef __WXMAC__
+  return stream.Write("\r", 1);
+#else
+  return stream.Write("\n", 1);
+#endif
+#endif
+}
+
+#endif
+  // wxUSE_STREAMS