]> git.saurik.com Git - wxWidgets.git/blobdiff - src/common/stream.cpp
Don't use "Cancel" button in the about dialog of the listctrl sample.
[wxWidgets.git] / src / common / stream.cpp
index 73dde47896f15a1c358f7d203881d98ec6d6ffe2..f7cd2ea2c58db63aa52248adc2857100f501c1e5 100644 (file)
 #include "wx/wxprec.h"
 
 #ifdef __BORLANDC__
 #include "wx/wxprec.h"
 
 #ifdef __BORLANDC__
-  #pragma hdrstop
+    #pragma hdrstop
 #endif
 
 #endif
 
+#if wxUSE_STREAMS
+
+#include "wx/stream.h"
+
 #ifndef WX_PRECOMP
 #ifndef WX_PRECOMP
-  #include "wx/defs.h"
+    #include "wx/log.h"
 #endif
 
 #endif
 
-#if wxUSE_STREAMS
-
 #include <ctype.h>
 #include <ctype.h>
-#include "wx/stream.h"
 #include "wx/datstrm.h"
 #include "wx/textfile.h"
 #include "wx/datstrm.h"
 #include "wx/textfile.h"
-#include "wx/log.h"
+#include "wx/scopeguard.h"
 
 // ----------------------------------------------------------------------------
 // constants
 
 // ----------------------------------------------------------------------------
 // constants
@@ -63,7 +64,6 @@ void wxStreamBuffer::InitBuffer()
     m_buffer_start =
     m_buffer_end =
     m_buffer_pos = NULL;
     m_buffer_start =
     m_buffer_end =
     m_buffer_pos = NULL;
-    m_buffer_size = 0;
 
     // if we are going to allocate the buffer, we should free it later as well
     m_destroybuf = true;
 
     // if we are going to allocate the buffer, we should free it later as well
     m_destroybuf = true;
@@ -76,24 +76,24 @@ void wxStreamBuffer::Init()
     m_fixed = true;
 }
 
     m_fixed = true;
 }
 
-wxStreamBuffer::wxStreamBuffer(BufMode mode)
+void wxStreamBuffer::InitWithStream(wxStreamBase& stream, BufMode mode)
 {
     Init();
 
 {
     Init();
 
-    m_stream = NULL;
+    m_stream = &stream;
     m_mode = mode;
 
     m_mode = mode;
 
-    m_flushable = false;
+    m_flushable = true;
 }
 
 }
 
-wxStreamBuffer::wxStreamBuffer(wxStreamBase& stream, BufMode mode)
+wxStreamBuffer::wxStreamBuffer(BufMode mode)
 {
     Init();
 
 {
     Init();
 
-    m_stream = &stream;
+    m_stream = NULL;
     m_mode = mode;
 
     m_mode = mode;
 
-    m_flushable = true;
+    m_flushable = false;
 }
 
 wxStreamBuffer::wxStreamBuffer(const wxStreamBuffer& buffer)
 }
 
 wxStreamBuffer::wxStreamBuffer(const wxStreamBuffer& buffer)
@@ -101,12 +101,11 @@ wxStreamBuffer::wxStreamBuffer(const wxStreamBuffer& buffer)
     // doing this has big chances to lead to a crash when the source buffer is
     // destroyed (otherwise assume the caller knows what he does)
     wxASSERT_MSG( !buffer.m_destroybuf,
     // doing this has big chances to lead to a crash when the source buffer is
     // destroyed (otherwise assume the caller knows what he does)
     wxASSERT_MSG( !buffer.m_destroybuf,
-                  _T("it's a bad idea to copy this buffer") );
+                  wxT("it's a bad idea to copy this buffer") );
 
     m_buffer_start = buffer.m_buffer_start;
     m_buffer_end = buffer.m_buffer_end;
     m_buffer_pos = buffer.m_buffer_pos;
 
     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_fixed = buffer.m_fixed;
     m_flushable = buffer.m_flushable;
     m_stream = buffer.m_stream;
@@ -156,8 +155,6 @@ void wxStreamBuffer::SetBufferIO(void *start,
     m_buffer_start = (char *)start;
     m_buffer_end   = m_buffer_start + len;
 
     m_buffer_start = (char *)start;
     m_buffer_end   = m_buffer_start + len;
 
-    m_buffer_size = len;
-
     // if we own it, we free it
     m_destroybuf = takeOwnership;
 
     // if we own it, we free it
     m_destroybuf = takeOwnership;
 
@@ -192,6 +189,27 @@ void wxStreamBuffer::ResetBuffer()
                         : m_buffer_start;
 }
 
                         : m_buffer_start;
 }
 
+void wxStreamBuffer::Truncate()
+{
+    size_t new_size = m_buffer_pos - m_buffer_start;
+    if ( m_buffer_pos == m_buffer_end )
+        return;
+
+    if ( !new_size )
+    {
+        FreeBuffer();
+        InitBuffer();
+        return;
+    }
+
+    char *new_start = (char *)realloc(m_buffer_start, new_size);
+    wxCHECK_RET( new_size, wxT("shrinking buffer shouldn't fail") );
+
+    m_buffer_start = new_start;
+    m_buffer_end = m_buffer_start + new_size;
+    m_buffer_pos = m_buffer_end;
+}
+
 // fill the buffer with as much data as possible (only for read buffers)
 bool wxStreamBuffer::FillBuffer()
 {
 // fill the buffer with as much data as possible (only for read buffers)
 bool wxStreamBuffer::FillBuffer()
 {
@@ -201,7 +219,7 @@ bool wxStreamBuffer::FillBuffer()
     if ( !inStream )
         return false;
 
     if ( !inStream )
         return false;
 
-    size_t count = inStream->OnSysRead(m_buffer_start, m_buffer_size);
+    size_t count = inStream->OnSysRead(GetBufferStart(), GetBufferSize());
     if ( !count )
         return false;
 
     if ( !count )
         return false;
 
@@ -214,7 +232,7 @@ bool wxStreamBuffer::FillBuffer()
 // write the buffer contents to the stream (only for write buffers)
 bool wxStreamBuffer::FlushBuffer()
 {
 // write the buffer contents to the stream (only for write buffers)
 bool wxStreamBuffer::FlushBuffer()
 {
-    wxCHECK_MSG( m_flushable, false, _T("can't flush this buffer") );
+    wxCHECK_MSG( m_flushable, false, wxT("can't flush this buffer") );
 
     // FIXME: what is this check for? (VZ)
     if ( m_buffer_pos == m_buffer_start )
 
     // FIXME: what is this check for? (VZ)
     if ( m_buffer_pos == m_buffer_start )
@@ -222,7 +240,7 @@ bool wxStreamBuffer::FlushBuffer()
 
     wxOutputStream *outStream = GetOutputStream();
 
 
     wxOutputStream *outStream = GetOutputStream();
 
-    wxCHECK_MSG( outStream, false, _T("should have a stream in wxStreamBuffer") );
+    wxCHECK_MSG( outStream, false, wxT("should have a stream in wxStreamBuffer") );
 
     size_t current = m_buffer_pos - m_buffer_start;
     size_t count = outStream->OnSysWrite(m_buffer_start, current);
 
     size_t current = m_buffer_pos - m_buffer_start;
     size_t count = outStream->OnSysWrite(m_buffer_start, current);
@@ -271,24 +289,26 @@ void wxStreamBuffer::PutToBuffer(const void *buffer, size_t size)
         else // !m_fixed
         {
             // realloc the buffer to have enough space for the data
         else // !m_fixed
         {
             // realloc the buffer to have enough space for the data
-            size_t delta = m_buffer_pos - m_buffer_start;
-
-            char *startOld = m_buffer_start;
-            m_buffer_size += size;
-            m_buffer_start = (char *)realloc(m_buffer_start, m_buffer_size);
-            if ( !m_buffer_start )
+            if ( m_buffer_pos + size > m_buffer_end )
             {
             {
-                // don't leak memory if realloc() failed
-                m_buffer_start = startOld;
-                m_buffer_size -= size;
+                size_t delta = m_buffer_pos - m_buffer_start;
+                size_t new_size = delta + size;
 
 
-                // what else can we do?
-                return;
-            }
+                char *startOld = m_buffer_start;
+                m_buffer_start = (char *)realloc(m_buffer_start, new_size);
+                if ( !m_buffer_start )
+                {
+                    // don't leak memory if realloc() failed
+                    m_buffer_start = startOld;
 
 
-            // adjust the pointers invalidated by realloc()
-            m_buffer_pos = m_buffer_start + delta;
-            m_buffer_end = m_buffer_start + m_buffer_size;
+                    // what else can we do?
+                    return;
+                }
+
+                // adjust the pointers invalidated by realloc()
+                m_buffer_pos = m_buffer_start + delta;
+                m_buffer_end = m_buffer_start + new_size;
+            } // else: the buffer is big enough
         }
     }
 
         }
     }
 
@@ -300,7 +320,7 @@ void wxStreamBuffer::PutChar(char c)
 {
     wxOutputStream *outStream = GetOutputStream();
 
 {
     wxOutputStream *outStream = GetOutputStream();
 
-    wxCHECK_RET( outStream, _T("should have a stream in wxStreamBuffer") );
+    wxCHECK_RET( outStream, wxT("should have a stream in wxStreamBuffer") );
 
     // if we don't have buffer at all, just forward this call to the stream,
     if ( !HasBuffer() )
 
     // if we don't have buffer at all, just forward this call to the stream,
     if ( !HasBuffer() )
@@ -326,7 +346,7 @@ void wxStreamBuffer::PutChar(char c)
 char wxStreamBuffer::Peek()
 {
     wxCHECK_MSG( m_stream && HasBuffer(), 0,
 char wxStreamBuffer::Peek()
 {
     wxCHECK_MSG( m_stream && HasBuffer(), 0,
-                 _T("should have the stream and the buffer in wxStreamBuffer") );
+                 wxT("should have the stream and the buffer in wxStreamBuffer") );
 
     if ( !GetDataLeft() )
     {
 
     if ( !GetDataLeft() )
     {
@@ -345,7 +365,7 @@ char wxStreamBuffer::GetChar()
 {
     wxInputStream *inStream = GetInputStream();
 
 {
     wxInputStream *inStream = GetInputStream();
 
-    wxCHECK_MSG( inStream, 0, _T("should have a stream in wxStreamBuffer") );
+    wxCHECK_MSG( inStream, 0, wxT("should have a stream in wxStreamBuffer") );
 
     char c;
     if ( !HasBuffer() )
 
     char c;
     if ( !HasBuffer() )
@@ -371,6 +391,11 @@ char wxStreamBuffer::GetChar()
 
 size_t wxStreamBuffer::Read(void *buffer, size_t size)
 {
 
 size_t wxStreamBuffer::Read(void *buffer, size_t size)
 {
+    wxASSERT_MSG( buffer, wxT("Warning: Null pointer is about to be used") );
+
+    /* Clear buffer first */
+    memset(buffer, 0x00, size);
+
     // lasterror is reset before all new IO calls
     if ( m_stream )
         m_stream->Reset();
     // lasterror is reset before all new IO calls
     if ( m_stream )
         m_stream->Reset();
@@ -380,7 +405,7 @@ size_t wxStreamBuffer::Read(void *buffer, size_t size)
     {
         wxInputStream *inStream = GetInputStream();
 
     {
         wxInputStream *inStream = GetInputStream();
 
-        wxCHECK_MSG( inStream, 0, _T("should have a stream in wxStreamBuffer") );
+        wxCHECK_MSG( inStream, 0, wxT("should have a stream in wxStreamBuffer") );
 
         readBytes = inStream->OnSysRead(buffer, size);
     }
 
         readBytes = inStream->OnSysRead(buffer, size);
     }
@@ -425,7 +450,7 @@ size_t wxStreamBuffer::Read(void *buffer, size_t size)
 // this should really be called "Copy()"
 size_t wxStreamBuffer::Read(wxStreamBuffer *dbuf)
 {
 // this should really be called "Copy()"
 size_t wxStreamBuffer::Read(wxStreamBuffer *dbuf)
 {
-    wxCHECK_MSG( m_mode != write, 0, _T("can't read from this buffer") );
+    wxCHECK_MSG( m_mode != write, 0, wxT("can't read from this buffer") );
 
     char buf[BUF_TEMP_SIZE];
     size_t nRead,
 
     char buf[BUF_TEMP_SIZE];
     size_t nRead,
@@ -447,6 +472,8 @@ size_t wxStreamBuffer::Read(wxStreamBuffer *dbuf)
 
 size_t wxStreamBuffer::Write(const void *buffer, size_t size)
 {
 
 size_t wxStreamBuffer::Write(const void *buffer, size_t size)
 {
+    wxASSERT_MSG( buffer, wxT("Warning: Null pointer is about to be send") );
+
     if (m_stream)
     {
         // lasterror is reset before all new IO calls
     if (m_stream)
     {
         // lasterror is reset before all new IO calls
@@ -459,7 +486,7 @@ size_t wxStreamBuffer::Write(const void *buffer, size_t size)
     {
         wxOutputStream *outStream = GetOutputStream();
 
     {
         wxOutputStream *outStream = GetOutputStream();
 
-        wxCHECK_MSG( outStream, 0, _T("should have a stream in wxStreamBuffer") );
+        wxCHECK_MSG( outStream, 0, wxT("should have a stream in wxStreamBuffer") );
 
         // no buffer, just forward the call to the stream
         ret = outStream->OnSysWrite(buffer, size);
 
         // no buffer, just forward the call to the stream
         ret = outStream->OnSysWrite(buffer, size);
@@ -517,8 +544,8 @@ size_t wxStreamBuffer::Write(const void *buffer, size_t size)
 
 size_t wxStreamBuffer::Write(wxStreamBuffer *sbuf)
 {
 
 size_t wxStreamBuffer::Write(wxStreamBuffer *sbuf)
 {
-    wxCHECK_MSG( m_mode != read, 0, _T("can't write to this buffer") );
-    wxCHECK_MSG( sbuf->m_mode != write, 0, _T("can't read from that buffer") );
+    wxCHECK_MSG( m_mode != read, 0, wxT("can't write to this buffer") );
+    wxCHECK_MSG( sbuf->m_mode != write, 0, wxT("can't read from that buffer") );
 
     char buf[BUF_TEMP_SIZE];
     size_t nWrite,
 
     char buf[BUF_TEMP_SIZE];
     size_t nWrite,
@@ -573,7 +600,7 @@ wxFileOffset wxStreamBuffer::Seek(wxFileOffset pos, wxSeekMode mode)
                 break;
 
             default:
                 break;
 
             default:
-                wxFAIL_MSG( _T("invalid seek mode") );
+                wxFAIL_MSG( wxT("invalid seek mode") );
 
                 return wxInvalidOffset;
         }
 
                 return wxInvalidOffset;
         }
@@ -609,7 +636,7 @@ wxFileOffset wxStreamBuffer::Seek(wxFileOffset pos, wxSeekMode mode)
                 size_t int_diff = wx_truncate_cast(size_t, diff);
                 wxCHECK_MSG( (wxFileOffset)int_diff == diff, wxInvalidOffset, wxT("huge file not supported") );
                 SetIntPosition(int_diff);
                 size_t int_diff = wx_truncate_cast(size_t, diff);
                 wxCHECK_MSG( (wxFileOffset)int_diff == diff, wxInvalidOffset, wxT("huge file not supported") );
                 SetIntPosition(int_diff);
-                return pos;
+                return diff;
             }
 
         case wxFromEnd:
             }
 
         case wxFromEnd:
@@ -650,6 +677,8 @@ wxFileOffset wxStreamBuffer::Tell() const
 // wxStreamBase
 // ----------------------------------------------------------------------------
 
 // wxStreamBase
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_ABSTRACT_CLASS(wxStreamBase, wxObject)
+
 wxStreamBase::wxStreamBase()
 {
     m_lasterror = wxSTREAM_NO_ERROR;
 wxStreamBase::wxStreamBase()
 {
     m_lasterror = wxSTREAM_NO_ERROR;
@@ -663,11 +692,11 @@ wxStreamBase::~wxStreamBase()
 size_t wxStreamBase::GetSize() const
 {
     wxFileOffset length = GetLength();
 size_t wxStreamBase::GetSize() const
 {
     wxFileOffset length = GetLength();
-    if ( length == wxInvalidOffset )
+    if ( length == (wxFileOffset)wxInvalidOffset )
         return 0;
 
     const size_t len = wx_truncate_cast(size_t, length);
         return 0;
 
     const size_t len = wx_truncate_cast(size_t, length);
-    wxASSERT_MSG( len == length + size_t(0), _T("large files not supported") );
+    wxASSERT_MSG( len == length + size_t(0), wxT("large files not supported") );
 
     return len;
 }
 
     return len;
 }
@@ -686,6 +715,8 @@ wxFileOffset wxStreamBase::OnSysTell() const
 // wxInputStream
 // ----------------------------------------------------------------------------
 
 // wxInputStream
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_ABSTRACT_CLASS(wxInputStream, wxStreamBase)
+
 wxInputStream::wxInputStream()
 {
     m_wback = NULL;
 wxInputStream::wxInputStream()
 {
     m_wback = NULL;
@@ -741,6 +772,11 @@ char *wxInputStream::AllocSpaceWBack(size_t needed_size)
 
 size_t wxInputStream::GetWBack(void *buf, size_t size)
 {
 
 size_t wxInputStream::GetWBack(void *buf, size_t size)
 {
+    wxASSERT_MSG( buf, wxT("Warning: Null pointer is about to be used") );
+
+    /* Clear buffer first */
+    memset(buf, 0x00, size);
+
     if (!m_wback)
         return 0;
 
     if (!m_wback)
         return 0;
 
@@ -772,6 +808,8 @@ size_t wxInputStream::GetWBack(void *buf, size_t size)
 
 size_t wxInputStream::Ungetch(const void *buf, size_t bufsize)
 {
 
 size_t wxInputStream::Ungetch(const void *buf, size_t bufsize)
 {
+    wxASSERT_MSG( buf, wxT("Warning: Null pointer is about to be used in Ungetch()") );
+
     if ( m_lasterror != wxSTREAM_NO_ERROR && m_lasterror != wxSTREAM_EOF )
     {
         // can't operate on this stream until the error is cleared
     if ( m_lasterror != wxSTREAM_NO_ERROR && m_lasterror != wxSTREAM_EOF )
     {
         // can't operate on this stream until the error is cleared
@@ -795,15 +833,17 @@ bool wxInputStream::Ungetch(char c)
     return Ungetch(&c, sizeof(c)) != 0;
 }
 
     return Ungetch(&c, sizeof(c)) != 0;
 }
 
-char wxInputStream::GetC()
+int wxInputStream::GetC()
 {
 {
-    char c;
+    unsigned char c;
     Read(&c, sizeof(c));
     Read(&c, sizeof(c));
-    return c;
+    return LastRead() ? c : wxEOF;
 }
 
 wxInputStream& wxInputStream::Read(void *buf, size_t size)
 {
 }
 
 wxInputStream& wxInputStream::Read(void *buf, size_t size)
 {
+    wxASSERT_MSG( buf, wxT("Warning: Null pointer is about to be read") );
+
     char *p = (char *)buf;
     m_lastcount = 0;
 
     char *p = (char *)buf;
     m_lastcount = 0;
 
@@ -853,6 +893,7 @@ char wxInputStream::Peek()
 
 wxInputStream& wxInputStream::Read(wxOutputStream& stream_out)
 {
 
 wxInputStream& wxInputStream::Read(wxOutputStream& stream_out)
 {
+    size_t lastcount = 0;
     char buf[BUF_TEMP_SIZE];
 
     for ( ;; )
     char buf[BUF_TEMP_SIZE];
 
     for ( ;; )
@@ -863,8 +904,12 @@ wxInputStream& wxInputStream::Read(wxOutputStream& stream_out)
 
         if ( stream_out.Write(buf, bytes_read).LastWrite() != bytes_read )
             break;
 
         if ( stream_out.Write(buf, bytes_read).LastWrite() != bytes_read )
             break;
+
+        lastcount += bytes_read;
     }
 
     }
 
+    m_lastcount = lastcount;
+
     return *this;
 }
 
     return *this;
 }
 
@@ -872,13 +917,48 @@ wxFileOffset wxInputStream::SeekI(wxFileOffset pos, wxSeekMode mode)
 {
     // RR: This code is duplicated in wxBufferedInputStream. This is
     // not really a good design, but buffered stream are different
 {
     // RR: This code is duplicated in wxBufferedInputStream. This is
     // not really a good design, but buffered stream are different
-    // from all other in that they handle two stream-related objects,
+    // from all others in that they handle two stream-related objects:
     // the stream buffer and parent stream.
 
     // I don't know whether it should be put as well in wxFileInputStream::OnSysSeek
     if (m_lasterror==wxSTREAM_EOF)
         m_lasterror=wxSTREAM_NO_ERROR;
 
     // the stream buffer and parent stream.
 
     // I don't know whether it should be put as well in wxFileInputStream::OnSysSeek
     if (m_lasterror==wxSTREAM_EOF)
         m_lasterror=wxSTREAM_NO_ERROR;
 
+    // avoid unnecessary seek operations (optimization)
+    wxFileOffset currentPos = TellI(), size = GetLength();
+    if ((mode == wxFromStart && currentPos == pos) ||
+        (mode == wxFromCurrent && pos == 0) ||
+        (mode == wxFromEnd && size != wxInvalidOffset && currentPos == size-pos))
+        return currentPos;
+
+    if (!IsSeekable() && mode == wxFromCurrent && pos > 0)
+    {
+        // rather than seeking, we can just read data and discard it;
+        // this allows to forward-seek also non-seekable streams!
+        char buf[BUF_TEMP_SIZE];
+        size_t bytes_read;
+
+        // read chunks of BUF_TEMP_SIZE bytes until we reach the new position
+        for ( ; pos >= BUF_TEMP_SIZE; pos -= bytes_read)
+        {
+            bytes_read = Read(buf, WXSIZEOF(buf)).LastRead();
+            if ( m_lasterror != wxSTREAM_NO_ERROR )
+                return wxInvalidOffset;
+
+            wxASSERT(bytes_read == WXSIZEOF(buf));
+        }
+
+        // read the last 'pos' bytes
+        bytes_read = Read(buf, (size_t)pos).LastRead();
+        if ( m_lasterror != wxSTREAM_NO_ERROR )
+            return wxInvalidOffset;
+
+        wxASSERT(bytes_read == (size_t)pos);
+
+        // we should now have sought to the right position...
+        return TellI();
+    }
+
     /* RR: A call to SeekI() will automatically invalidate any previous
        call to Ungetch(), otherwise it would be possible to SeekI() to
        one position, unread some bytes there, SeekI() to another position
     /* RR: A call to SeekI() will automatically invalidate any previous
        call to Ungetch(), otherwise it would be possible to SeekI() to
        one position, unread some bytes there, SeekI() to another position
@@ -917,6 +997,8 @@ wxFileOffset wxInputStream::TellI() const
 // wxOutputStream
 // ----------------------------------------------------------------------------
 
 // wxOutputStream
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_ABSTRACT_CLASS(wxOutputStream, wxStreamBase)
+
 wxOutputStream::wxOutputStream()
 {
 }
 wxOutputStream::wxOutputStream()
 {
 }
@@ -967,6 +1049,8 @@ void wxOutputStream::Sync()
 // wxCountingOutputStream
 // ----------------------------------------------------------------------------
 
 // wxCountingOutputStream
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_DYNAMIC_CLASS(wxCountingOutputStream, wxOutputStream)
+
 wxCountingOutputStream::wxCountingOutputStream ()
 {
      m_currentPos = 0;
 wxCountingOutputStream::wxCountingOutputStream ()
 {
      m_currentPos = 0;
@@ -1008,7 +1092,7 @@ wxFileOffset wxCountingOutputStream::OnSysSeek(wxFileOffset pos, wxSeekMode mode
             break;
 
         default:
             break;
 
         default:
-            wxFAIL_MSG( _T("invalid seek mode") );
+            wxFAIL_MSG( wxT("invalid seek mode") );
             return wxInvalidOffset;
     }
 
             return wxInvalidOffset;
     }
 
@@ -1029,59 +1113,162 @@ wxFileOffset wxCountingOutputStream::OnSysTell() const
 // wxFilterInputStream
 // ----------------------------------------------------------------------------
 
 // wxFilterInputStream
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_ABSTRACT_CLASS(wxFilterInputStream, wxInputStream)
+
 wxFilterInputStream::wxFilterInputStream()
 wxFilterInputStream::wxFilterInputStream()
+ :  m_parent_i_stream(NULL),
+    m_owns(false)
 {
 {
-    m_parent_i_stream = NULL;
 }
 
 wxFilterInputStream::wxFilterInputStream(wxInputStream& stream)
 }
 
 wxFilterInputStream::wxFilterInputStream(wxInputStream& stream)
+ :  m_parent_i_stream(&stream),
+    m_owns(false)
+{
+}
+
+wxFilterInputStream::wxFilterInputStream(wxInputStream *stream)
+ :  m_parent_i_stream(stream),
+    m_owns(true)
 {
 {
-    m_parent_i_stream = &stream;
 }
 
 wxFilterInputStream::~wxFilterInputStream()
 {
 }
 
 wxFilterInputStream::~wxFilterInputStream()
 {
+    if (m_owns)
+        delete m_parent_i_stream;
 }
 
 // ----------------------------------------------------------------------------
 // wxFilterOutputStream
 // ----------------------------------------------------------------------------
 
 }
 
 // ----------------------------------------------------------------------------
 // wxFilterOutputStream
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_ABSTRACT_CLASS(wxFilterOutputStream, wxOutputStream)
+
 wxFilterOutputStream::wxFilterOutputStream()
 wxFilterOutputStream::wxFilterOutputStream()
+ :  m_parent_o_stream(NULL),
+    m_owns(false)
 {
 {
-    m_parent_o_stream = NULL;
 }
 
 wxFilterOutputStream::wxFilterOutputStream(wxOutputStream& stream)
 }
 
 wxFilterOutputStream::wxFilterOutputStream(wxOutputStream& stream)
+ :  m_parent_o_stream(&stream),
+    m_owns(false)
+{
+}
+
+wxFilterOutputStream::wxFilterOutputStream(wxOutputStream *stream)
+ :  m_parent_o_stream(stream),
+    m_owns(true)
+{
+}
+
+bool wxFilterOutputStream::Close()
 {
 {
-    m_parent_o_stream = &stream;
+    if (m_parent_o_stream && m_owns)
+        return m_parent_o_stream->Close();
+    else
+        return true;
 }
 
 wxFilterOutputStream::~wxFilterOutputStream()
 {
 }
 
 wxFilterOutputStream::~wxFilterOutputStream()
 {
+    if (m_owns)
+        delete m_parent_o_stream;
 }
 
 // ----------------------------------------------------------------------------
 }
 
 // ----------------------------------------------------------------------------
-// wxBufferedInputStream
+// wxFilterClassFactoryBase
 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 
-wxBufferedInputStream::wxBufferedInputStream(wxInputStream& s,
-                                             wxStreamBuffer *buffer)
-                     : wxFilterInputStream(s)
+IMPLEMENT_ABSTRACT_CLASS(wxFilterClassFactoryBase, wxObject)
+
+wxString wxFilterClassFactoryBase::PopExtension(const wxString& location) const
+{
+    return location.substr(0, FindExtension(location));
+}
+
+wxString::size_type wxFilterClassFactoryBase::FindExtension(
+        const wxString& location) const
 {
 {
-    if ( buffer )
+    for (const wxChar *const *p = GetProtocols(wxSTREAM_FILEEXT); *p; p++)
     {
     {
-        // use the buffer provided by the user
-        m_i_streambuf = buffer;
+        if ( location.EndsWith(*p) )
+            return location.length() - wxStrlen(*p);
     }
     }
-    else // create a default buffer
+
+    return wxString::npos;
+}
+
+bool wxFilterClassFactoryBase::CanHandle(const wxString& protocol,
+                                         wxStreamProtocolType type) const
+{
+    if (type == wxSTREAM_FILEEXT)
+        return FindExtension(protocol) != wxString::npos;
+    else
+        for (const wxChar *const *p = GetProtocols(type); *p; p++)
+            if (protocol == *p)
+                return true;
+
+    return false;
+}
+
+// ----------------------------------------------------------------------------
+// wxFilterClassFactory
+// ----------------------------------------------------------------------------
+
+IMPLEMENT_ABSTRACT_CLASS(wxFilterClassFactory, wxFilterClassFactoryBase)
+
+wxFilterClassFactory *wxFilterClassFactory::sm_first = NULL;
+
+void wxFilterClassFactory::Remove()
+{
+    if (m_next != this)
     {
     {
-        m_i_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::read);
+        wxFilterClassFactory **pp = &sm_first;
 
 
-        m_i_streambuf->SetBufferIO(1024);
+        while (*pp != this)
+            pp = &(*pp)->m_next;
+
+        *pp = m_next;
+
+        m_next = this;
     }
 }
 
     }
 }
 
+// ----------------------------------------------------------------------------
+// wxBufferedInputStream
+// ----------------------------------------------------------------------------
+
+namespace
+{
+
+// helper function used for initializing the buffer used by
+// wxBufferedInput/OutputStream: it simply returns the provided buffer if it's
+// not NULL or creates a buffer of the given size otherwise
+template <typename T>
+wxStreamBuffer *
+CreateBufferIfNeeded(T& stream, wxStreamBuffer *buffer, size_t bufsize = 1024)
+{
+    return buffer ? buffer : new wxStreamBuffer(bufsize, stream);
+}
+
+} // anonymous namespace
+
+wxBufferedInputStream::wxBufferedInputStream(wxInputStream& stream,
+                                             wxStreamBuffer *buffer)
+                     : wxFilterInputStream(stream)
+{
+    m_i_streambuf = CreateBufferIfNeeded(*this, buffer);
+}
+
+wxBufferedInputStream::wxBufferedInputStream(wxInputStream& stream,
+                                             size_t bufsize)
+                     : wxFilterInputStream(stream)
+{
+    m_i_streambuf = CreateBufferIfNeeded(*this, NULL, bufsize);
+}
+
 wxBufferedInputStream::~wxBufferedInputStream()
 {
     m_parent_i_stream->SeekI(-(wxFileOffset)m_i_streambuf->GetBytesLeft(),
 wxBufferedInputStream::~wxBufferedInputStream()
 {
     m_parent_i_stream->SeekI(-(wxFileOffset)m_i_streambuf->GetBytesLeft(),
@@ -1109,12 +1296,15 @@ wxInputStream& wxBufferedInputStream::Read(void *buf, size_t size)
         size -= m_lastcount;
         buf = (char *)buf + m_lastcount;
 
         size -= m_lastcount;
         buf = (char *)buf + m_lastcount;
 
-        // the call to wxStreamBuffer::Read() below will reset our m_lastcount,
-        // so save it
+        // the call to wxStreamBuffer::Read() below may reset our m_lastcount
+        // (but it also may not do it if the buffer is associated to another
+        // existing stream and wasn't created by us), so save it
         size_t countOld = m_lastcount;
 
         size_t countOld = m_lastcount;
 
-        m_i_streambuf->Read(buf, size);
+        // the new count of the bytes read is the count of bytes read this time
+        m_lastcount = m_i_streambuf->Read(buf, size);
 
 
+        // plus those we had read before
         m_lastcount += countOld;
     }
 
         m_lastcount += countOld;
     }
 
@@ -1168,7 +1358,7 @@ wxFileOffset wxBufferedInputStream::OnSysTell() const
 
 void wxBufferedInputStream::SetInputStreamBuffer(wxStreamBuffer *buffer)
 {
 
 void wxBufferedInputStream::SetInputStreamBuffer(wxStreamBuffer *buffer)
 {
-    wxCHECK_RET( buffer, _T("wxBufferedInputStream needs buffer") );
+    wxCHECK_RET( buffer, wxT("wxBufferedInputStream needs buffer") );
 
     delete m_i_streambuf;
     m_i_streambuf = buffer;
 
     delete m_i_streambuf;
     m_i_streambuf = buffer;
@@ -1178,20 +1368,18 @@ void wxBufferedInputStream::SetInputStreamBuffer(wxStreamBuffer *buffer)
 // wxBufferedOutputStream
 // ----------------------------------------------------------------------------
 
 // wxBufferedOutputStream
 // ----------------------------------------------------------------------------
 
-wxBufferedOutputStream::wxBufferedOutputStream(wxOutputStream& s,
+wxBufferedOutputStream::wxBufferedOutputStream(wxOutputStream& stream,
                                                wxStreamBuffer *buffer)
                                                wxStreamBuffer *buffer)
-                      : wxFilterOutputStream(s)
+                      : wxFilterOutputStream(stream)
 {
 {
-    if ( buffer )
-    {
-        m_o_streambuf = buffer;
-    }
-    else // create a default one
-    {
-        m_o_streambuf = new wxStreamBuffer(*this, wxStreamBuffer::write);
+    m_o_streambuf = CreateBufferIfNeeded(*this, buffer);
+}
 
 
-        m_o_streambuf->SetBufferIO(1024);
-    }
+wxBufferedOutputStream::wxBufferedOutputStream(wxOutputStream& stream,
+                                               size_t bufsize)
+                      : wxFilterOutputStream(stream)
+{
+    m_o_streambuf = CreateBufferIfNeeded(*this, NULL, bufsize);
 }
 
 wxBufferedOutputStream::~wxBufferedOutputStream()
 }
 
 wxBufferedOutputStream::~wxBufferedOutputStream()
@@ -1253,12 +1441,99 @@ wxFileOffset wxBufferedOutputStream::GetLength() const
 
 void wxBufferedOutputStream::SetOutputStreamBuffer(wxStreamBuffer *buffer)
 {
 
 void wxBufferedOutputStream::SetOutputStreamBuffer(wxStreamBuffer *buffer)
 {
-    wxCHECK_RET( buffer, _T("wxBufferedOutputStream needs buffer") );
+    wxCHECK_RET( buffer, wxT("wxBufferedOutputStream needs buffer") );
 
     delete m_o_streambuf;
     m_o_streambuf = buffer;
 }
 
 
     delete m_o_streambuf;
     m_o_streambuf = buffer;
 }
 
+// ---------------------------------------------------------------------------
+// wxWrapperInputStream implementation
+// ---------------------------------------------------------------------------
+
+wxWrapperInputStream::wxWrapperInputStream()
+{
+    m_lasterror = wxSTREAM_READ_ERROR;
+}
+
+wxWrapperInputStream::wxWrapperInputStream(wxInputStream& stream)
+    : wxFilterInputStream(stream)
+{
+    SynchronizeLastError();
+}
+
+wxWrapperInputStream::wxWrapperInputStream(wxInputStream *stream)
+    : wxFilterInputStream(stream)
+{
+    if ( m_parent_i_stream )
+        SynchronizeLastError();
+    else
+        m_lasterror = wxSTREAM_READ_ERROR;
+}
+
+void wxWrapperInputStream::InitParentStream(wxInputStream& stream)
+{
+    wxCHECK_RET( !m_parent_i_stream, "Can't init parent stream twice" );
+
+    m_parent_i_stream = &stream;
+
+    SynchronizeLastError();
+}
+
+void wxWrapperInputStream::InitParentStream(wxInputStream* stream)
+{
+    wxCHECK_RET( !m_parent_i_stream, "Can't init parent stream twice" );
+
+    m_parent_i_stream = stream;
+
+    if ( m_parent_i_stream )
+    {
+        m_owns = true;
+
+        SynchronizeLastError();
+    }
+}
+
+wxFileOffset wxWrapperInputStream::GetLength() const
+{
+    wxCHECK_MSG(m_parent_i_stream, wxInvalidOffset, "Stream not valid");
+
+    wxON_BLOCK_EXIT_THIS0(wxWrapperInputStream::SynchronizeLastError);
+    return m_parent_i_stream->GetLength();
+}
+
+bool wxWrapperInputStream::IsSeekable() const
+{
+    wxCHECK_MSG(m_parent_i_stream, false, "Stream not valid");
+    return m_parent_i_stream->IsSeekable();
+}
+
+size_t wxWrapperInputStream::OnSysRead(void *buffer, size_t size)
+{
+    wxCHECK_MSG(m_parent_i_stream, false, "Stream not valid");
+
+    wxON_BLOCK_EXIT_THIS0(wxWrapperInputStream::SynchronizeLastError);
+
+    m_parent_i_stream->Read(buffer, size);
+    return m_parent_i_stream->LastRead();
+}
+
+wxFileOffset wxWrapperInputStream::OnSysSeek(wxFileOffset pos, wxSeekMode mode)
+{
+    wxCHECK_MSG(IsSeekable(), false, "Stream not seekable");
+
+    wxON_BLOCK_EXIT_THIS0(wxWrapperInputStream::SynchronizeLastError);
+    return m_parent_i_stream->SeekI (pos, mode);
+}
+
+wxFileOffset wxWrapperInputStream::OnSysTell() const
+{
+    wxCHECK_MSG(m_parent_i_stream, false, "Stream not valid");
+
+    wxON_BLOCK_EXIT_THIS0(wxWrapperInputStream::SynchronizeLastError);
+    return m_parent_i_stream->TellI();
+}
+
 // ----------------------------------------------------------------------------
 // Some IOManip function
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // Some IOManip function
 // ----------------------------------------------------------------------------