]> git.saurik.com Git - wxWidgets.git/blobdiff - include/wx/stream.h
Make wxChoice and wxComboBox behaviour same as in native controls in wxMSW.
[wxWidgets.git] / include / wx / stream.h
index c2574995f40d840bc08e4fead49a7591daa873f9..80c81bcbdc0a8f32bd6aeb1de583dee4cb36fd29 100644 (file)
@@ -1,21 +1,17 @@
 /////////////////////////////////////////////////////////////////////////////
 // Name:        wx/stream.h
-// Purpose:     "wxWindows stream" base classes
-// Author:      Guilhem Lavaux
+// Purpose:     stream classes
+// Author:      Guilhem Lavaux, Guillermo Rodriguez Garcia, Vadim Zeitlin
 // Modified by:
 // Created:     11/07/98
 // RCS-ID:      $Id$
 // Copyright:   (c) Guilhem Lavaux
-// Licence:     wxWindows license
+// Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 #ifndef _WX_WXSTREAM_H__
 #define _WX_WXSTREAM_H__
 
-#ifdef __GNUG__
-#pragma interface
-#endif
-
 #include "wx/defs.h"
 
 #if wxUSE_STREAMS
 #include <stdio.h>
 #include "wx/object.h"
 #include "wx/string.h"
-#include "wx/filefn.h"  // for off_t, wxInvalidOffset and wxSeekMode
+#include "wx/filefn.h"  // for wxFileOffset, wxInvalidOffset and wxSeekMode
 
-class WXDLLEXPORT wxStreamBase;
-class WXDLLEXPORT wxInputStream;
-class WXDLLEXPORT wxOutputStream;
+class WXDLLIMPEXP_FWD_BASE wxStreamBase;
+class WXDLLIMPEXP_FWD_BASE wxInputStream;
+class WXDLLIMPEXP_FWD_BASE wxOutputStream;
 
 typedef wxInputStream& (*__wxInputManip)(wxInputStream&);
 typedef wxOutputStream& (*__wxOutputManip)(wxOutputStream&);
 
-WXDLLEXPORT wxOutputStream& wxEndL(wxOutputStream& o_stream);
+WXDLLIMPEXP_BASE wxOutputStream& wxEndL(wxOutputStream& o_stream);
 
-// ---------------------------------------------------------------------------
-// wxStream: base classes
-// ---------------------------------------------------------------------------
+// ----------------------------------------------------------------------------
+// constants
+// ----------------------------------------------------------------------------
 
 enum wxStreamError
 {
-  wxSTREAM_NO_ERROR = 0,
-  wxSTREAM_NO_ERR = wxSTREAM_NO_ERROR,
-  wxSTREAM_NOERROR = wxSTREAM_NO_ERROR,
+    wxSTREAM_NO_ERROR = 0,      // stream is in good state
+    wxSTREAM_EOF,               // EOF reached in Read() or similar
+    wxSTREAM_WRITE_ERROR,       // generic write error
+    wxSTREAM_READ_ERROR         // generic read error
+};
 
-  wxSTREAM_EOF,
+const int wxEOF = -1;
 
-  wxSTREAM_WRITE_ERROR,
-  wxSTREAM_WRITE_ERR = wxSTREAM_WRITE_ERROR,
+// ============================================================================
+// base stream classes: wxInputStream and wxOutputStream
+// ============================================================================
 
-  wxSTREAM_READ_ERROR,
-  wxSTREAM_READ_ERR = wxSTREAM_READ_ERROR
-};
-
-// compatibility
-#define wxStream_NOERROR    wxSTREAM_NOERROR
-#define wxStream_EOF        wxSTREAM_EOF
-#define wxStream_WRITE_ERR  wxSTREAM_WRITE_ERROR
-#define wxStream_READ_ERR   wxSTREAM_READ_ERROR
+// ---------------------------------------------------------------------------
+// wxStreamBase: common (but non virtual!) base for all stream classes
+// ---------------------------------------------------------------------------
 
-class WXDLLEXPORT wxStreamBase
+class WXDLLIMPEXP_BASE wxStreamBase : public wxObject
 {
 public:
     wxStreamBase();
     virtual ~wxStreamBase();
 
     // error testing
-    wxStreamError LastError() const { return m_lasterror; }
     wxStreamError GetLastError() const { return m_lasterror; }
-    bool IsOk() const { return LastError() == wxSTREAM_NOERROR; }
-    bool operator!() const { return LastError() != wxSTREAM_NOERROR; }
+    virtual bool IsOk() const { return GetLastError() == wxSTREAM_NO_ERROR; }
+    bool operator!() const { return !IsOk(); }
 
-    virtual size_t GetSize() const { return ~((size_t)0); }
-    size_t StreamSize() const { return GetSize(); }
+    // reset the stream state
+    void Reset(wxStreamError error = wxSTREAM_NO_ERROR) { m_lasterror = error; }
 
-protected:
-    virtual size_t OnSysRead(void *buffer, size_t bufsize);
-    virtual size_t OnSysWrite(const void *buffer, size_t bufsize);
-    virtual off_t OnSysSeek(off_t seek, wxSeekMode mode);
-    virtual off_t OnSysTell() const;
+    // this doesn't make sense for all streams, always test its return value
+    virtual size_t GetSize() const;
+    virtual wxFileOffset GetLength() const { return wxInvalidOffset; }
 
-    friend class wxStreamBuffer;
+    // returns true if the streams supports seeking to arbitrary offsets
+    virtual bool IsSeekable() const { return false; }
+
+protected:
+    virtual wxFileOffset OnSysSeek(wxFileOffset seek, wxSeekMode mode);
+    virtual wxFileOffset OnSysTell() const;
 
     size_t m_lastcount;
     wxStreamError m_lasterror;
+
+    friend class wxStreamBuffer;
+
+    DECLARE_ABSTRACT_CLASS(wxStreamBase)
+    wxDECLARE_NO_COPY_CLASS(wxStreamBase);
 };
 
-class WXDLLEXPORT wxInputStream: public wxStreamBase
+// ----------------------------------------------------------------------------
+// wxInputStream: base class for the input streams
+// ----------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxInputStream : public wxStreamBase
 {
 public:
+    // ctor and dtor, nothing exciting
     wxInputStream();
     virtual ~wxInputStream();
 
-    // is the stream at EOF?
-    virtual bool Eof() const;
 
     // IO functions
+    // ------------
+
+    // return a character from the stream without removing it, i.e. it will
+    // still be returned by the next call to GetC()
+    //
+    // blocks until something appears in the stream if necessary, if nothing
+    // ever does (i.e. EOF) LastRead() will return 0 (and the return value is
+    // undefined), otherwise 1
     virtual char Peek();
-    char GetC();
+
+    // return one byte from the stream, blocking until it appears if
+    // necessary
+    //
+    // on success returns a value between 0 - 255, or wxEOF on EOF or error.
+    int GetC();
+
+    // read at most the given number of bytes from the stream
+    //
+    // there are 2 possible situations here: either there is nothing at all in
+    // the stream right now in which case Read() blocks until something appears
+    // (use CanRead() to avoid this) or there is already some data available in
+    // the stream and then Read() doesn't block but returns just the data it
+    // can read without waiting for more
+    //
+    // in any case, if there are not enough bytes in the stream right now,
+    // LastRead() value will be less than size but greater than 0. If it is 0,
+    // it means that EOF has been reached.
     virtual wxInputStream& Read(void *buffer, size_t size);
-    wxInputStream& Read(wxOutputStream& stream_out);
 
-    // Position functions
-    virtual off_t SeekI(off_t pos, wxSeekMode mode = wxFromStart);
-    virtual off_t TellI() const;
+    // copy the entire contents of this stream into streamOut, stopping only
+    // when EOF is reached or an error occurs
+    wxInputStream& Read(wxOutputStream& streamOut);
+
+
+    // status functions
+    // ----------------
+
+    // returns the number of bytes read by the last call to Read(), GetC() or
+    // Peek()
+    //
+    // this should be used to discover whether that call succeeded in reading
+    // all the requested data or not
+    virtual size_t LastRead() const { return wxStreamBase::m_lastcount; }
 
-    // State functions
-    virtual size_t LastRead() { return wxStreamBase::m_lastcount; }
+    // returns true if some data is available in the stream right now, so that
+    // calling Read() wouldn't block
+    virtual bool CanRead() const;
 
-    // Ungetch
+    // is the stream at EOF?
+    //
+    // note that this cannot be really implemented for all streams and
+    // CanRead() is more reliable than Eof()
+    virtual bool Eof() const;
+
+
+    // write back buffer
+    // -----------------
+
+    // put back the specified number of bytes into the stream, they will be
+    // fetched by the next call to the read functions
+    //
+    // returns the number of bytes really stuffed back
     size_t Ungetch(const void *buffer, size_t size);
+
+    // put back the specified character in the stream
+    //
+    // returns true if ok, false on error
     bool Ungetch(char c);
 
-    // Operators
+
+    // position functions
+    // ------------------
+
+    // move the stream pointer to the given position (if the stream supports
+    // it)
+    //
+    // returns wxInvalidOffset on error
+    virtual wxFileOffset SeekI(wxFileOffset pos, wxSeekMode mode = wxFromStart);
+
+    // return the current position of the stream pointer or wxInvalidOffset
+    virtual wxFileOffset TellI() const;
+
+
+    // stream-like operators
+    // ---------------------
+
     wxInputStream& operator>>(wxOutputStream& out) { return Read(out); }
-#if wxUSE_SERIAL
-    wxInputStream& operator>>(wxObject *& obj);
-#endif
-    wxInputStream& operator>>( __wxInputManip func) { return func(*this); }
+    wxInputStream& operator>>(__wxInputManip func) { return func(*this); }
 
 protected:
-    // Ungetch managers
+    // do read up to size bytes of data into the provided buffer
+    //
+    // this method should return 0 if EOF has been reached or an error occurred
+    // (m_lasterror should be set accordingly as well) or the number of bytes
+    // read
+    virtual size_t OnSysRead(void *buffer, size_t size) = 0;
+
+    // write-back buffer support
+    // -------------------------
+
+    // return the pointer to a buffer big enough to hold sizeNeeded bytes
+    char *AllocSpaceWBack(size_t sizeNeeded);
+
+    // read up to size data from the write back buffer, return the number of
+    // bytes read
+    size_t GetWBack(void *buf, size_t size);
+
+    // write back buffer or NULL if none
     char *m_wback;
+
+    // the size of the buffer
     size_t m_wbacksize;
+
+    // the current position in the buffer
     size_t m_wbackcur;
 
-    char *AllocSpaceWBack(size_t needed_size);
-    size_t GetWBack(void *buf, size_t bsize);
+    friend class wxStreamBuffer;
+
+    DECLARE_ABSTRACT_CLASS(wxInputStream)
+    wxDECLARE_NO_COPY_CLASS(wxInputStream);
 };
 
-class WXDLLEXPORT wxOutputStream: public wxStreamBase
+// ----------------------------------------------------------------------------
+// wxOutputStream: base for the output streams
+// ----------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxOutputStream : public wxStreamBase
 {
 public:
     wxOutputStream();
@@ -139,77 +235,178 @@ public:
     virtual wxOutputStream& Write(const void *buffer, size_t size);
     wxOutputStream& Write(wxInputStream& stream_in);
 
-    virtual off_t SeekO(off_t pos, wxSeekMode mode = wxFromStart);
-    virtual off_t TellO() const;
+    virtual wxFileOffset SeekO(wxFileOffset pos, wxSeekMode mode = wxFromStart);
+    virtual wxFileOffset TellO() const;
 
     virtual size_t LastWrite() const { return wxStreamBase::m_lastcount; }
 
     virtual void Sync();
+    virtual bool Close() { return true; }
 
     wxOutputStream& operator<<(wxInputStream& out) { return Write(out); }
-#if wxUSE_SERIAL
-    wxOutputStream& operator<<(wxObject& obj);
-#endif
     wxOutputStream& operator<<( __wxOutputManip func) { return func(*this); }
+
+protected:
+    // to be implemented in the derived classes (it should have been pure
+    // virtual)
+    virtual size_t OnSysWrite(const void *buffer, size_t bufsize);
+
+    friend class wxStreamBuffer;
+
+    DECLARE_ABSTRACT_CLASS(wxOutputStream)
+    wxDECLARE_NO_COPY_CLASS(wxOutputStream);
 };
 
+// ============================================================================
+// helper stream classes
+// ============================================================================
+
 // ---------------------------------------------------------------------------
 // A stream for measuring streamed output
 // ---------------------------------------------------------------------------
 
-class WXDLLEXPORT wxCountingOutputStream: public wxOutputStream
+class WXDLLIMPEXP_BASE wxCountingOutputStream : public wxOutputStream
 {
 public:
     wxCountingOutputStream();
 
-    size_t GetSize() const;
-    bool Ok() const { return TRUE; }
+    wxFileOffset GetLength() const;
+    bool Ok() const { return IsOk(); }
+    bool IsOk() const { return true; }
 
 protected:
-    size_t OnSysWrite(const void *buffer, size_t size);
-    off_t OnSysSeek(off_t pos, wxSeekMode mode);
-    off_t OnSysTell() const;
+    virtual size_t OnSysWrite(const void *buffer, size_t size);
+    virtual wxFileOffset OnSysSeek(wxFileOffset pos, wxSeekMode mode);
+    virtual wxFileOffset OnSysTell() const;
 
     size_t m_currentPos;
+
+    DECLARE_DYNAMIC_CLASS(wxCountingOutputStream)
+    wxDECLARE_NO_COPY_CLASS(wxCountingOutputStream);
 };
 
 // ---------------------------------------------------------------------------
 // "Filter" streams
 // ---------------------------------------------------------------------------
 
-class WXDLLEXPORT wxFilterInputStream: public wxInputStream
+class WXDLLIMPEXP_BASE wxFilterInputStream : public wxInputStream
 {
 public:
     wxFilterInputStream();
     wxFilterInputStream(wxInputStream& stream);
-    ~wxFilterInputStream();
+    wxFilterInputStream(wxInputStream *stream);
+    virtual ~wxFilterInputStream();
 
     char Peek() { return m_parent_i_stream->Peek(); }
 
-    size_t GetSize() const { return m_parent_i_stream->GetSize(); }
+    wxFileOffset GetLength() const { return m_parent_i_stream->GetLength(); }
+
+    wxInputStream *GetFilterInputStream() const { return m_parent_i_stream; }
 
 protected:
     wxInputStream *m_parent_i_stream;
+    bool m_owns;
+
+    DECLARE_ABSTRACT_CLASS(wxFilterInputStream)
+    wxDECLARE_NO_COPY_CLASS(wxFilterInputStream);
 };
 
-class WXDLLEXPORT wxFilterOutputStream: public wxOutputStream
+class WXDLLIMPEXP_BASE wxFilterOutputStream : public wxOutputStream
 {
 public:
     wxFilterOutputStream();
     wxFilterOutputStream(wxOutputStream& stream);
-    ~wxFilterOutputStream();
+    wxFilterOutputStream(wxOutputStream *stream);
+    virtual ~wxFilterOutputStream();
+
+    wxFileOffset GetLength() const { return m_parent_o_stream->GetLength(); }
+
+    wxOutputStream *GetFilterOutputStream() const { return m_parent_o_stream; }
 
-    size_t GetSize() const { return m_parent_o_stream->GetSize(); }
+    bool Close();
 
 protected:
     wxOutputStream *m_parent_o_stream;
+    bool m_owns;
+
+    DECLARE_ABSTRACT_CLASS(wxFilterOutputStream)
+    wxDECLARE_NO_COPY_CLASS(wxFilterOutputStream);
+};
+
+enum wxStreamProtocolType
+{
+    wxSTREAM_PROTOCOL,  // wxFileSystem protocol (should be only one)
+    wxSTREAM_MIMETYPE,  // MIME types the stream handles
+    wxSTREAM_ENCODING,  // The HTTP Content-Encodings the stream handles
+    wxSTREAM_FILEEXT    // File extensions the stream handles
+};
+
+void WXDLLIMPEXP_BASE wxUseFilterClasses();
+
+class WXDLLIMPEXP_BASE wxFilterClassFactoryBase : public wxObject
+{
+public:
+    virtual ~wxFilterClassFactoryBase() { }
+
+    wxString GetProtocol() const { return wxString(*GetProtocols()); }
+    wxString PopExtension(const wxString& location) const;
+
+    virtual const wxChar * const *GetProtocols(wxStreamProtocolType type
+                                               = wxSTREAM_PROTOCOL) const = 0;
+
+    bool CanHandle(const wxString& protocol,
+                   wxStreamProtocolType type
+                   = wxSTREAM_PROTOCOL) const;
+
+protected:
+    wxString::size_type FindExtension(const wxString& location) const;
+
+    DECLARE_ABSTRACT_CLASS(wxFilterClassFactoryBase)
 };
 
+class WXDLLIMPEXP_BASE wxFilterClassFactory : public wxFilterClassFactoryBase
+{
+public:
+    virtual ~wxFilterClassFactory() { }
+
+    virtual wxFilterInputStream  *NewStream(wxInputStream& stream)  const = 0;
+    virtual wxFilterOutputStream *NewStream(wxOutputStream& stream) const = 0;
+    virtual wxFilterInputStream  *NewStream(wxInputStream *stream)  const = 0;
+    virtual wxFilterOutputStream *NewStream(wxOutputStream *stream) const = 0;
+
+    static const wxFilterClassFactory *Find(const wxString& protocol,
+                                            wxStreamProtocolType type
+                                            = wxSTREAM_PROTOCOL);
+
+    static const wxFilterClassFactory *GetFirst();
+    const wxFilterClassFactory *GetNext() const { return m_next; }
+
+    void PushFront() { Remove(); m_next = sm_first; sm_first = this; }
+    void Remove();
+
+protected:
+    wxFilterClassFactory() : m_next(this) { }
+
+    wxFilterClassFactory& operator=(const wxFilterClassFactory&)
+        { return *this; }
+
+private:
+    static wxFilterClassFactory *sm_first;
+    wxFilterClassFactory *m_next;
+
+    DECLARE_ABSTRACT_CLASS(wxFilterClassFactory)
+};
+
+// ============================================================================
+// buffered streams
+// ============================================================================
+
 // ---------------------------------------------------------------------------
-// Stream buffer
+// Stream buffer: this class can be derived from and passed to
+// wxBufferedStreams to implement custom buffering
 // ---------------------------------------------------------------------------
 
-class WXDLLEXPORT wxStreamBuffer
+class WXDLLIMPEXP_BASE wxStreamBuffer
 {
 public:
     enum BufMode
@@ -219,35 +416,51 @@ public:
         read_write
     };
 
-    wxStreamBuffer(wxStreamBase& stream, BufMode mode);
-    wxStreamBuffer(BufMode mode);
+    wxStreamBuffer(wxStreamBase& stream, BufMode mode)
+    {
+        InitWithStream(stream, mode);
+    }
+
+    wxStreamBuffer(size_t bufsize, wxInputStream& stream)
+    {
+        InitWithStream(stream, read);
+        SetBufferIO(bufsize);
+    }
+
+    wxStreamBuffer(size_t bufsize, wxOutputStream& stream)
+    {
+        InitWithStream(stream, write);
+        SetBufferIO(bufsize);
+    }
+
     wxStreamBuffer(const wxStreamBuffer& buf);
-    ~wxStreamBuffer();
+    virtual ~wxStreamBuffer();
 
     // Filtered IO
-    size_t Read(void *buffer, size_t size);
+    virtual size_t Read(void *buffer, size_t size);
     size_t Read(wxStreamBuffer *buf);
-    size_t Write(const void *buffer, size_t size);
+    virtual size_t Write(const void *buffer, size_t size);
     size_t Write(wxStreamBuffer *buf);
 
-    char Peek();
-    char GetChar();
-    void PutChar(char c);
-    off_t Tell() const;
-    off_t Seek(off_t pos, wxSeekMode mode);
+    virtual char Peek();
+    virtual char GetChar();
+    virtual void PutChar(char c);
+    virtual wxFileOffset Tell() const;
+    virtual wxFileOffset Seek(wxFileOffset pos, wxSeekMode mode);
 
     // Buffer control
     void ResetBuffer();
+    void Truncate();
 
     // NB: the buffer must always be allocated with malloc() if takeOwn is
-    //     TRUE as it will be deallocated by free()
-    void SetBufferIO(void *start, void *end, bool takeOwnership = FALSE);
-    void SetBufferIO(void *start, size_t len, bool takeOwnership = FALSE);
+    //     true as it will be deallocated by free()
+    void SetBufferIO(void *start, void *end, bool takeOwnership = false);
+    void SetBufferIO(void *start, size_t len, bool takeOwnership = false);
     void SetBufferIO(size_t bufsize);
     void *GetBufferStart() const { return m_buffer_start; }
     void *GetBufferEnd() const { return m_buffer_end; }
     void *GetBufferPos() const { return m_buffer_pos; }
-    size_t GetBufferSize() const { return m_buffer_size; }
+    size_t GetBufferSize() const { return m_buffer_end - m_buffer_start; }
     size_t GetIntPosition() const { return m_buffer_pos - m_buffer_start; }
     void SetIntPosition(size_t pos) { m_buffer_pos = m_buffer_start + pos; }
     size_t GetLastAccess() const { return m_buffer_end - m_buffer_start; }
@@ -262,13 +475,23 @@ public:
 
     // misc accessors
     wxStreamBase *GetStream() const { return m_stream; }
-    bool HasBuffer() const { return m_buffer_size != 0; }
+    bool HasBuffer() const { return m_buffer_start != m_buffer_end; }
 
     bool IsFixed() const { return m_fixed; }
     bool IsFlushable() const { return m_flushable; }
 
+    // only for input/output buffers respectively, returns NULL otherwise
+    wxInputStream *GetInputStream() const;
+    wxOutputStream *GetOutputStream() const;
+
+#if WXWIN_COMPATIBILITY_2_6
     // deprecated, for compatibility only
-    wxStreamBase *Stream() { return m_stream; }
+    wxDEPRECATED( wxStreamBase *Stream() );
+#endif // WXWIN_COMPATIBILITY_2_6
+
+    // this constructs a dummy wxStreamBuffer, used by (and exists for)
+    // wxMemoryStreams only, don't use!
+    wxStreamBuffer(BufMode mode);
 
 protected:
     void GetFromBuffer(void *buffer, size_t size);
@@ -280,6 +503,9 @@ protected:
     // common part of several ctors
     void Init();
 
+    // common part of ctors taking wxStreamBase parameter
+    void InitWithStream(wxStreamBase& stream, BufMode mode);
+
     // init buffer variables to be empty
     void InitBuffer();
 
@@ -292,10 +518,6 @@ protected:
          *m_buffer_end,
          *m_buffer_pos;
 
-    // the buffer size
-    // FIXME: isn't it the same as m_buffer_end - m_buffer_start? (VZ)
-    size_t m_buffer_size;
-
     // the stream we're associated with
     wxStreamBase *m_stream;
 
@@ -304,66 +526,168 @@ protected:
 
     // flags
     bool m_destroybuf,      // deallocate buffer?
-         m_destroystream,   // delete associated stream?
          m_fixed,
          m_flushable;
+
+
+    wxDECLARE_NO_ASSIGN_CLASS(wxStreamBuffer);
 };
 
 // ---------------------------------------------------------------------------
-// wxBufferedStreams
+// wxBufferedInputStream
 // ---------------------------------------------------------------------------
 
-class WXDLLEXPORT wxBufferedInputStream: public wxFilterInputStream
+class WXDLLIMPEXP_BASE wxBufferedInputStream : public wxFilterInputStream
 {
 public:
-    wxBufferedInputStream(wxInputStream& stream);
-    ~wxBufferedInputStream();
+    // create a buffered stream on top of the specified low-level stream
+    //
+    // if a non NULL buffer is given to the stream, it will be deleted by it,
+    // otherwise a default 1KB buffer will be used
+    wxBufferedInputStream(wxInputStream& stream,
+                          wxStreamBuffer *buffer = NULL);
+
+    // ctor allowing to specify the buffer size, it's just a more convenient
+    // alternative to creating wxStreamBuffer, calling its SetBufferIO(bufsize)
+    // and using the ctor above
+    wxBufferedInputStream(wxInputStream& stream, size_t bufsize);
+
+
+    virtual ~wxBufferedInputStream();
 
     char Peek();
     wxInputStream& Read(void *buffer, size_t size);
 
     // Position functions
-    off_t SeekI(off_t pos, wxSeekMode mode = wxFromStart);
-    off_t TellI() const;
+    wxFileOffset SeekI(wxFileOffset pos, wxSeekMode mode = wxFromStart);
+    wxFileOffset TellI() const;
+    bool IsSeekable() const { return m_parent_i_stream->IsSeekable(); }
 
-    wxStreamBuffer *InputStreamBuffer() const { return m_i_streambuf; }
+    // the buffer given to the stream will be deleted by it
+    void SetInputStreamBuffer(wxStreamBuffer *buffer);
+    wxStreamBuffer *GetInputStreamBuffer() const { return m_i_streambuf; }
+
+#if WXWIN_COMPATIBILITY_2_6
+    // deprecated, for compatibility only
+    wxDEPRECATED( wxStreamBuffer *InputStreamBuffer() const );
+#endif // WXWIN_COMPATIBILITY_2_6
 
 protected:
-    size_t OnSysRead(void *buffer, size_t bufsize);
-    off_t OnSysSeek(off_t seek, wxSeekMode mode);
-    off_t OnSysTell() const;
+    virtual size_t OnSysRead(void *buffer, size_t bufsize);
+    virtual wxFileOffset OnSysSeek(wxFileOffset seek, wxSeekMode mode);
+    virtual wxFileOffset OnSysTell() const;
 
     wxStreamBuffer *m_i_streambuf;
+
+    wxDECLARE_NO_COPY_CLASS(wxBufferedInputStream);
 };
 
-class WXDLLEXPORT wxBufferedOutputStream: public wxFilterOutputStream
+// ----------------------------------------------------------------------------
+// wxBufferedOutputStream
+// ----------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxBufferedOutputStream : public wxFilterOutputStream
 {
 public:
-    wxBufferedOutputStream(wxOutputStream& stream);
-    ~wxBufferedOutputStream();
+    // create a buffered stream on top of the specified low-level stream
+    //
+    // if a non NULL buffer is given to the stream, it will be deleted by it,
+    // otherwise a default 1KB buffer will be used
+    wxBufferedOutputStream(wxOutputStream& stream,
+                           wxStreamBuffer *buffer = NULL);
+
+    // ctor allowing to specify the buffer size, it's just a more convenient
+    // alternative to creating wxStreamBuffer, calling its SetBufferIO(bufsize)
+    // and using the ctor above
+    wxBufferedOutputStream(wxOutputStream& stream, size_t bufsize);
+
+    virtual ~wxBufferedOutputStream();
 
     wxOutputStream& Write(const void *buffer, size_t size);
 
     // Position functions
-    off_t SeekO(off_t pos, wxSeekMode mode = wxFromStart);
-    off_t TellO() const;
+    wxFileOffset SeekO(wxFileOffset pos, wxSeekMode mode = wxFromStart);
+    wxFileOffset TellO() const;
+    bool IsSeekable() const { return m_parent_o_stream->IsSeekable(); }
 
     void Sync();
+    bool Close();
+
+    wxFileOffset GetLength() const;
 
-    size_t GetSize() const;
+    // the buffer given to the stream will be deleted by it
+    void SetOutputStreamBuffer(wxStreamBuffer *buffer);
+    wxStreamBuffer *GetOutputStreamBuffer() const { return m_o_streambuf; }
 
-    wxStreamBuffer *OutputStreamBuffer() const { return m_o_streambuf; }
+#if WXWIN_COMPATIBILITY_2_6
+    // deprecated, for compatibility only
+    wxDEPRECATED( wxStreamBuffer *OutputStreamBuffer() const );
+#endif // WXWIN_COMPATIBILITY_2_6
 
 protected:
-    size_t OnSysWrite(const void *buffer, size_t bufsize);
-    off_t OnSysSeek(off_t seek, wxSeekMode mode);
-    off_t OnSysTell() const;
+    virtual size_t OnSysWrite(const void *buffer, size_t bufsize);
+    virtual wxFileOffset OnSysSeek(wxFileOffset seek, wxSeekMode mode);
+    virtual wxFileOffset OnSysTell() const;
 
     wxStreamBuffer *m_o_streambuf;
+
+    wxDECLARE_NO_COPY_CLASS(wxBufferedOutputStream);
+};
+
+#if WXWIN_COMPATIBILITY_2_6
+    inline wxStreamBase *wxStreamBuffer::Stream() { return m_stream; }
+    inline wxStreamBuffer *wxBufferedInputStream::InputStreamBuffer() const { return m_i_streambuf; }
+    inline wxStreamBuffer *wxBufferedOutputStream::OutputStreamBuffer() const { return m_o_streambuf; }
+#endif // WXWIN_COMPATIBILITY_2_6
+
+// ---------------------------------------------------------------------------
+// wxWrapperInputStream: forwards all IO to another stream.
+// ---------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxWrapperInputStream : public wxFilterInputStream
+{
+public:
+    // Constructor fully initializing the stream. The overload taking pointer
+    // takes ownership of the parent stream, the one taking reference does not.
+    //
+    // Notice that this class also has a default ctor but it's protected as the
+    // derived class is supposed to take care of calling InitParentStream() if
+    // it's used.
+    wxWrapperInputStream(wxInputStream& stream);
+    wxWrapperInputStream(wxInputStream* stream);
+
+    // Override the base class methods to forward to the wrapped stream.
+    virtual wxFileOffset GetLength() const;
+    virtual bool IsSeekable() const;
+
+protected:
+    virtual size_t OnSysRead(void *buffer, size_t size);
+    virtual wxFileOffset OnSysSeek(wxFileOffset pos, wxSeekMode mode);
+    virtual wxFileOffset OnSysTell() const;
+
+    // Ensure that our own last error is the same as that of the real stream.
+    //
+    // This method is const because the error must be updated even from const
+    // methods (in other words, it really should have been mutable in the first
+    // place).
+    void SynchronizeLastError() const
+    {
+        const_cast<wxWrapperInputStream*>(this)->
+            Reset(m_parent_i_stream->GetLastError());
+    }
+
+    // Default constructor, use InitParentStream() later.
+    wxWrapperInputStream();
+
+    // Set up the wrapped stream for an object initialized using the default
+    // constructor. The ownership logic is the same as above.
+    void InitParentStream(wxInputStream& stream);
+    void InitParentStream(wxInputStream* stream);
+
+    wxDECLARE_NO_COPY_CLASS(wxWrapperInputStream);
 };
 
-#endif
-  // wxUSE_STREAMS
 
-#endif
-  // _WX_WXSTREAM_H__
+#endif // wxUSE_STREAMS
+
+#endif // _WX_WXSTREAM_H__