X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/e2acb9ae1c69c1e37cbe0e46933929f5b1b021ba..748a3af8e74ce74fe143650af0b2da2534c70d45:/src/common/stream.cpp

diff --git a/src/common/stream.cpp b/src/common/stream.cpp
index fdfc912333..310f1ee7e0 100644
--- a/src/common/stream.cpp
+++ b/src/common/stream.cpp
@@ -27,9 +27,9 @@
 #if wxUSE_STREAMS
 
 #include <ctype.h>
-#include <wx/stream.h>
-#include <wx/datstrm.h>
-#include <wx/objstrm.h>
+#include "wx/stream.h"
+#include "wx/datstrm.h"
+#include "wx/objstrm.h"
 
 #define BUF_TEMP_SIZE 10000
 
@@ -98,9 +98,9 @@ void wxStreamBuffer::SetBufferIO(size_t bufsize)
     wxDELETEA(m_buffer_start);
 
   if (!bufsize) {
-    m_buffer_start = NULL;
-    m_buffer_end = NULL;
-    m_buffer_pos = NULL;
+    m_buffer_start = (char*)NULL;
+    m_buffer_end = (char*)NULL;
+    m_buffer_pos = (char*)NULL;
     m_buffer_size = 0;
     return;
   }
@@ -114,7 +114,7 @@ void wxStreamBuffer::ResetBuffer()
 {
   m_stream->m_lasterror = wxStream_NOERROR;
   m_stream->m_lastcount = 0;
-  if (m_mode == read)
+  if (m_mode == read && m_flushable)
     m_buffer_pos = m_buffer_end;
   else
     m_buffer_pos = m_buffer_start;
@@ -165,10 +165,17 @@ 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) {
-    m_buffer_start = (char *)realloc(m_buffer_start, m_buffer_size+size);
-    // I round a bit
-    m_buffer_size += size;
-    m_buffer_end = m_buffer_start+m_buffer_size;
+    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)
@@ -195,6 +202,23 @@ void wxStreamBuffer::PutChar(char c)
   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;
@@ -212,7 +236,7 @@ char wxStreamBuffer::GetChar()
   }
 
   GetFromBuffer(&c, 1);
-  
+
   m_stream->m_lastcount = 1;
   return c;
 }
@@ -238,7 +262,7 @@ size_t wxStreamBuffer::Read(void *buffer, size_t size)
   size_t buf_left, orig_size = size;
 
   while (size > 0) {
-    buf_left = GetDataLeft(); 
+    buf_left = GetDataLeft();
 
     // First case: the requested buffer is larger than the stream buffer,
     //             we split it.
@@ -248,7 +272,7 @@ size_t wxStreamBuffer::Read(void *buffer, size_t size)
       buffer = (char *)buffer + buf_left; // ANSI C++ violation.
 
       if (!FillBuffer()) {
-        CHECK_ERROR(wxStream_READ_ERR);
+        CHECK_ERROR(wxStream_EOF);
         return (m_stream->m_lastcount = orig_size-size);
       }
     } else {
@@ -289,7 +313,7 @@ size_t wxStreamBuffer::Write(const void *buffer, size_t size)
   // ------------------
 
   m_stream->m_lasterror = wxStream_NOERROR;
-  if (!m_buffer_size)
+  if (!m_buffer_size && m_fixed)
     return (m_stream->m_lastcount = m_stream->OnSysWrite(buffer, size));
 
   // ------------------
@@ -303,7 +327,9 @@ size_t wxStreamBuffer::Write(const void *buffer, size_t size)
 
     // First case: the buffer to write is larger than the stream buffer,
     //             we split it
-    if (size > buf_left) {
+    // 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.
@@ -353,7 +379,12 @@ off_t wxStreamBuffer::Seek(off_t pos, wxSeekMode mode)
   last_access = GetLastAccess();
 
   if (!m_flushable) {
-    diff = pos + GetIntPosition();
+    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);
@@ -392,22 +423,25 @@ off_t wxStreamBuffer::Seek(off_t pos, wxSeekMode mode)
 
 off_t wxStreamBuffer::Tell() const
 {
-  off_t pos;
-
-  if (m_flushable) {
-    pos = m_stream->OnSysTell();
+    off_t pos = m_stream->OnSysTell();
     if (pos == wxInvalidOffset)
-      return wxInvalidOffset;
-    return pos - GetLastAccess() + GetIntPosition();
-  } else
-    return GetIntPosition();
+        return wxInvalidOffset;
+
+    pos += GetIntPosition();
+
+    if (m_mode == read && m_flushable)
+        pos -= GetLastAccess();
+
+    return pos;
 }
 
 size_t wxStreamBuffer::GetDataLeft()
 {
-  if (m_buffer_end == m_buffer_pos && m_flushable)
-    FillBuffer();
-  return m_buffer_end-m_buffer_pos;
+    /* Why is this done? RR. */
+    if (m_buffer_end == m_buffer_pos && m_flushable)
+        FillBuffer();
+
+    return m_buffer_end-m_buffer_pos;
 }
 
 // ----------------------------------------------------------------------------
@@ -416,8 +450,8 @@ size_t wxStreamBuffer::GetDataLeft()
 
 wxStreamBase::wxStreamBase()
 {
-  m_lasterror = wxStream_NOERROR;
-  m_lastcount = 0;
+    m_lasterror = wxStream_NOERROR;
+    m_lastcount = 0;
 }
 
 wxStreamBase::~wxStreamBase()
@@ -426,22 +460,22 @@ wxStreamBase::~wxStreamBase()
 
 size_t wxStreamBase::OnSysRead(void *WXUNUSED(buffer), size_t WXUNUSED(size))
 {
-  return 0;
+    return 0;
 }
 
 size_t wxStreamBase::OnSysWrite(const void *WXUNUSED(buffer), size_t WXUNUSED(bufsize))
 {
-  return 0;
+    return 0;
 }
 
 off_t wxStreamBase::OnSysSeek(off_t WXUNUSED(seek), wxSeekMode WXUNUSED(mode))
 {
-  return wxInvalidOffset;
+    return wxInvalidOffset;
 }
 
 off_t wxStreamBase::OnSysTell() const
 {
-  return wxInvalidOffset;
+    return wxInvalidOffset;
 }
 
 // ----------------------------------------------------------------------------
@@ -460,128 +494,180 @@ wxInputStream::~wxInputStream()
     free(m_wback);
 }
 
+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)
 {
-  char *temp_b;
+    /* get number of bytes left from previous wback buffer */
+    size_t toget = m_wbacksize - m_wbackcur;
 
-  m_wbacksize += needed_size;
+    /* allocate a buffer large enough to hold prev + new data */
+    char *temp_b = (char *) malloc(needed_size + toget);
 
-  if (!m_wback)
-    temp_b = (char *)malloc(m_wbacksize);
-  else
-    temp_b = (char *)realloc(m_wback, m_wbacksize);
+    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);
+    }
 
-  if (!temp_b)
-    return NULL;
-  m_wback = temp_b;
-  
-  return (char *)(m_wback+(m_wbacksize-needed_size));
+    /* 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;
+    size_t s_toget = m_wbacksize-m_wbackcur;
 
-  if (!m_wback)
-    return 0;
+    if (!m_wback)
+        return 0;
 
-  if (bsize < s_toget)
-    s_toget = bsize;
+    if (bsize < s_toget)
+       s_toget = bsize;
 
-  memcpy(buf, (m_wback+m_wbackcur), s_toget);
+    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;
+    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;
-
-  ptrback = AllocSpaceWBack(bufsize);
-  if (!ptrback)
-    return 0;
+    char *ptrback = AllocSpaceWBack(bufsize);
+    if (!ptrback)
+        return 0;
 
-  memcpy(ptrback, buf, bufsize);
-  return bufsize;
+    memcpy(ptrback, buf, bufsize);
+    return bufsize;
 }
 
 bool wxInputStream::Ungetch(char c)
 {
-  char *ptrback;
-
-  ptrback = AllocSpaceWBack(1);
-  if (!ptrback)
-    return FALSE;
+    char * ptrback = AllocSpaceWBack(1);
+    if (!ptrback)
+        return FALSE;
 
-  *ptrback = c;
-  return TRUE;
+    *ptrback = c;
+    return TRUE;
 }
 
 char wxInputStream::GetC()
 {
-  char c;
-  Read(&c, 1);
-  return c;
+    char c;
+    Read(&c, 1);
+    return c;
 }
 
 wxInputStream& wxInputStream::Read(void *buffer, size_t size)
 {
-  size_t retsize;
-  char *buf = (char *)buffer;
+    char *buf = (char *)buffer;
 
-  retsize = GetWBack(buf, size);
-  if (retsize == size) {
-    m_lastcount = size;
-    m_lasterror = wxStream_NOERROR;
-    return *this;
-  }
-  size     -= retsize;
-  buf      += retsize;
+    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);
-  return *this;
+    m_lastcount = OnSysRead(buf, size) + retsize;
+    return *this;
 }
 
 char wxInputStream::Peek()
 {
-  char c;
+    char c;
+    Read(&c, 1);
+    if (m_lasterror == wxStream_NOERROR)
+    {
+        Ungetch(c);
+        return c;
+    }
 
-  Read(&c, 1);
-  if (m_lasterror == wxStream_NOERROR) {
-    Ungetch(c);
-    return c;
-  }
-  return 0;
+    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) {
-    bytes_read = Read(buf, bytes_read).LastRead();
-    bytes_read = stream_out.Write(buf, bytes_read).LastWrite();
-  }
-  return *this;
+    while (bytes_read == BUF_TEMP_SIZE)
+    {
+        bytes_read = Read(buf, bytes_read).LastRead();
+        bytes_read = stream_out.Write(buf, bytes_read).LastWrite();
+    }
+    return *this;
 }
 
 off_t wxInputStream::SeekI(off_t pos, wxSeekMode mode)
 {
-  return OnSysSeek(pos, 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
 {
-  return OnSysTell();
+    /* GRG: Changed to make it compatible with the wback buffer */
+    off_t pos = OnSysTell();
+
+    if (pos != wxInvalidOffset)
+        pos -= (m_wbacksize - m_wbackcur);
+
+    return pos;
 }
 
 // --------------------
@@ -591,9 +677,9 @@ off_t wxInputStream::TellI() const
 #if wxUSE_SERIAL
 wxInputStream& wxInputStream::operator>>(wxObject *& obj)
 {
-  wxObjectInputStream obj_s(*this);
-  obj = obj_s.LoadObject();
-  return *this;
+    wxObjectInputStream obj_s(*this);
+    obj = obj_s.LoadObject();
+    return *this;
 }
 #endif
 
@@ -610,26 +696,31 @@ 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;
+    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();
+    return OnSysTell();
 }
 
 off_t wxOutputStream::SeekO(off_t pos, wxSeekMode mode)
 {
-  return OnSysSeek(pos, mode);
+    return OnSysSeek(pos, mode);
 }
 
 void wxOutputStream::Sync()
@@ -639,9 +730,9 @@ void wxOutputStream::Sync()
 #if wxUSE_SERIAL
 wxOutputStream& wxOutputStream::operator<<(wxObject& obj)
 {
-  wxObjectOutputStream obj_s(*this);
-  obj_s.SaveObject(obj);
-  return *this;
+    wxObjectOutputStream obj_s(*this);
+    obj_s.SaveObject(obj);
+    return *this;
 }
 #endif
 
@@ -652,45 +743,40 @@ wxOutputStream& wxOutputStream::operator<<(wxObject& obj)
 wxCountingOutputStream::wxCountingOutputStream ()
   : wxOutputStream()
 {
-   m_currentPos = 0;
+     m_currentPos = 0;
 }
 
 size_t wxCountingOutputStream::GetSize() const
 {
-  return m_lastcount;
+    return m_lastcount;
 }
 
-size_t wxCountingOutputStream::OnSysWrite(const void *buffer, size_t size)
+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;
+    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;  // ?
+    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;  // ?
+    return m_currentPos;
 }
-  
+
 // ----------------------------------------------------------------------------
 // wxFilterInputStream
 // ----------------------------------------------------------------------------
@@ -703,7 +789,7 @@ wxFilterInputStream::wxFilterInputStream()
 wxFilterInputStream::wxFilterInputStream(wxInputStream& stream)
   : wxInputStream()
 {
-  m_parent_i_stream = &stream;
+    m_parent_i_stream = &stream;
 }
 
 wxFilterInputStream::~wxFilterInputStream()
@@ -721,7 +807,7 @@ wxFilterOutputStream::wxFilterOutputStream()
 wxFilterOutputStream::wxFilterOutputStream(wxOutputStream& stream)
   : wxOutputStream()
 {
-  m_parent_o_stream = &stream;
+    m_parent_o_stream = &stream;
 }
 
 wxFilterOutputStream::~wxFilterOutputStream()
@@ -734,59 +820,69 @@ wxFilterOutputStream::~wxFilterOutputStream()
 wxBufferedInputStream::wxBufferedInputStream(wxInputStream& s)
   : wxFilterInputStream(s)
 {
-  m_i_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::read);
-  m_i_streambuf->SetBufferIO(1024);
+    m_i_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::read);
+    m_i_streambuf->SetBufferIO(1024);
 }
 
 wxBufferedInputStream::~wxBufferedInputStream()
 {
-  delete m_i_streambuf;
+    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;
+    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;
+    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);
+    m_i_streambuf->Read(buf, size);
 
-  return *this;
+    return *this;
 }
 
 off_t wxBufferedInputStream::SeekI(off_t pos, wxSeekMode mode)
 {
-  return m_i_streambuf->Seek(pos, mode);
+    return m_i_streambuf->Seek(pos, mode);
 }
 
 off_t wxBufferedInputStream::TellI() const
 {
-  return m_i_streambuf->Tell();
+    return m_i_streambuf->Tell();
 }
 
 size_t wxBufferedInputStream::OnSysRead(void *buffer, size_t bufsize)
 {
-  return m_parent_i_stream->Read(buffer, bufsize).LastRead();
+    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);
+    return m_parent_i_stream->SeekI(seek, mode);
 }
 
 off_t wxBufferedInputStream::OnSysTell() const
 {
-  return m_parent_i_stream->TellI();
+    return m_parent_i_stream->TellI();
 }
 
+
 // ----------------------------------------------------------------------------
 // wxBufferedOutputStream
 // ----------------------------------------------------------------------------
@@ -794,51 +890,58 @@ off_t wxBufferedInputStream::OnSysTell() const
 wxBufferedOutputStream::wxBufferedOutputStream(wxOutputStream& s)
   : wxFilterOutputStream(s)
 {
-  m_o_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::write);
-  m_o_streambuf->SetBufferIO(1024);
+    m_o_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::write);
+    m_o_streambuf->SetBufferIO(1024);
 }
 
 wxBufferedOutputStream::~wxBufferedOutputStream()
 {
-  delete m_o_streambuf;
+    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;
+    m_lastcount = 0;
+    m_o_streambuf->Write(buffer, size);
+    return *this;
 }
 
 off_t wxBufferedOutputStream::SeekO(off_t pos, wxSeekMode mode)
 {
-  return m_o_streambuf->Seek(pos, mode);
+    Sync();
+    return m_o_streambuf->Seek(pos, mode);
 }
 
 off_t wxBufferedOutputStream::TellO() const
 {
-  return m_o_streambuf->Tell();
+    return m_o_streambuf->Tell();
 }
 
 void wxBufferedOutputStream::Sync()
 {
-  m_o_streambuf->FlushBuffer();
-  m_parent_o_stream->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();
+    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);
+    return m_parent_o_stream->SeekO(seek, mode);
 }
 
 off_t wxBufferedOutputStream::OnSysTell() const
 {
-  return m_parent_o_stream->TellO();
+    return m_parent_o_stream->TellO();
+}
+
+size_t wxBufferedOutputStream::GetSize() const
+{
+   return m_parent_o_stream->GetSize() + m_o_streambuf->GetIntPosition();
 }
 
 // ----------------------------------------------------------------------------