/////////////////////////////////////////////////////////////////////////////
// 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
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
+#pragma interface "stream.h"
#endif
#include "wx/defs.h"
#include "wx/string.h"
#include "wx/filefn.h" // for off_t, wxInvalidOffset and wxSeekMode
-class WXDLLEXPORT wxStreamBase;
-class WXDLLEXPORT wxInputStream;
-class WXDLLEXPORT wxOutputStream;
+class WXDLLIMPEXP_BASE wxStreamBase;
+class WXDLLIMPEXP_BASE wxInputStream;
+class WXDLLIMPEXP_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_EOF,
-
- wxSTREAM_WRITE_ERROR,
- wxSTREAM_WRITE_ERR = wxSTREAM_WRITE_ERROR,
-
- wxSTREAM_READ_ERROR,
- wxSTREAM_READ_ERR = wxSTREAM_READ_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
};
// 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
+#if WXWIN_COMPATIBILITY_2_2
+ #define wxStream_NOERROR wxSTREAM_NOERROR
+ #define wxStream_EOF wxSTREAM_EOF
+ #define wxStream_WRITE_ERR wxSTREAM_WRITE_ERROR
+ #define wxStream_READ_ERR wxSTREAM_READ_ERROR
+
+ #define wxSTREAM_NO_ERR wxSTREAM_NO_ERROR
+ #define wxSTREAM_NOERROR wxSTREAM_NO_ERROR
+ #define wxSTREAM_WRITE_ERR wxSTREAM_WRITE_ERROR
+ #define wxSTREAM_READ_ERR wxSTREAM_READ_ERROR
+#endif // WXWIN_COMPATIBILITY_2_2
+
+// ============================================================================
+// base stream classes: wxInputStream and wxOutputStream
+// ============================================================================
-class WXDLLEXPORT wxStreamBase
+// ---------------------------------------------------------------------------
+// wxStreamBase: common (but non virtual!) base for all stream classes
+// ---------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxStreamBase
{
public:
wxStreamBase();
// error testing
wxStreamError GetLastError() const { return m_lasterror; }
- bool IsOk() const { return LastError() == wxSTREAM_NOERROR; }
- bool operator!() const { return LastError() != wxSTREAM_NOERROR; }
+ bool IsOk() const { return GetLastError() == wxSTREAM_NO_ERROR; }
+ bool operator!() const { return !IsOk(); }
+
+ // reset the stream state
+ void Reset() { m_lasterror = wxSTREAM_NO_ERROR; }
+ // this doesn't make sense for all streams, always test its return value
virtual size_t GetSize() const { return 0; }
+#if WXWIN_COMPATIBILITY_2_2
// deprecated, for compatibility only
wxStreamError LastError() const { return m_lasterror; }
size_t StreamSize() const { return GetSize(); }
+#endif // WXWIN_COMPATIBILITY_2_2
protected:
- // VZ: these functions are really pure virtual and shouldn't be declared
- // in the base class because it creates ambiguties in stream classes
- // deriving from both wxInputStream and wxOutputStream
-#if 0
- virtual size_t OnSysRead(void *buffer, size_t bufsize);
- virtual size_t OnSysWrite(const void *buffer, size_t bufsize);
-#endif
-
virtual off_t OnSysSeek(off_t seek, wxSeekMode mode);
virtual off_t OnSysTell() const;
- friend class wxStreamBuffer;
-
size_t m_lastcount;
wxStreamError m_lasterror;
+
+ friend class wxStreamBuffer;
+
+ DECLARE_NO_COPY_CLASS(wxStreamBase)
};
-class WXDLLEXPORT wxInputStream : /* virtual */ 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();
+
+ // return one character from the stream, blocking until it appears if
+ // necessary
+ //
+ // if EOF, return value is undefined and LastRead() will return 0 and not 1
char 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; }
+
+ // returns TRUE if some data is available in the stream right now, so that
+ // calling Read() wouldn't block
+ virtual bool CanRead() const;
+
+ // 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;
+
- // State functions
- virtual size_t LastRead() { return wxStreamBase::m_lastcount; }
+ // write back buffer
+ // -----------------
- // Ungetch
+ // 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 off_t SeekI(off_t pos, wxSeekMode mode = wxFromStart);
+
+ // return the current position of the stream pointer or wxInvalidOffset
+ virtual off_t TellI() const;
+
+
+ // stream-like operators
+ // ---------------------
+
wxInputStream& operator>>(wxOutputStream& out) { return Read(out); }
- wxInputStream& operator>>( __wxInputManip func) { return func(*this); }
+ wxInputStream& operator>>(__wxInputManip func) { return func(*this); }
protected:
- // to be implemented in the derived classes (it should have been pure
- // virtual)
- virtual size_t OnSysRead(void *buffer, size_t bufsize);
+ // 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 occured
+ // (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
+ // -------------------------
- // Ungetch managers
+ // 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;
- size_t m_wbackcur;
- char *AllocSpaceWBack(size_t needed_size);
- size_t GetWBack(void *buf, size_t bsize);
+ // the current position in the buffer
+ size_t m_wbackcur;
friend class wxStreamBuffer;
+
+ DECLARE_NO_COPY_CLASS(wxInputStream)
};
-class WXDLLEXPORT wxOutputStream : /* virtual */ public wxStreamBase
+// ----------------------------------------------------------------------------
+// wxOutputStream: base for the output streams
+// ----------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxOutputStream : public wxStreamBase
{
public:
wxOutputStream();
virtual size_t OnSysWrite(const void *buffer, size_t bufsize);
friend class wxStreamBuffer;
+
+ DECLARE_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();
virtual off_t OnSysTell() const;
size_t m_currentPos;
+
+ DECLARE_NO_COPY_CLASS(wxCountingOutputStream)
};
// ---------------------------------------------------------------------------
// "Filter" streams
// ---------------------------------------------------------------------------
-class WXDLLEXPORT wxFilterInputStream : public wxInputStream
+class WXDLLIMPEXP_BASE wxFilterInputStream : public wxInputStream
{
public:
wxFilterInputStream();
protected:
wxInputStream *m_parent_i_stream;
+
+ DECLARE_NO_COPY_CLASS(wxFilterInputStream)
};
-class WXDLLEXPORT wxFilterOutputStream : public wxOutputStream
+class WXDLLIMPEXP_BASE wxFilterOutputStream : public wxOutputStream
{
public:
wxFilterOutputStream();
protected:
wxOutputStream *m_parent_o_stream;
+
+ DECLARE_NO_COPY_CLASS(wxFilterOutputStream)
};
+// ============================================================================
+// buffered streams
+// ============================================================================
+
// ---------------------------------------------------------------------------
// 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
};
wxStreamBuffer(wxStreamBase& stream, BufMode mode);
- wxStreamBuffer(BufMode mode);
wxStreamBuffer(const wxStreamBuffer& buf);
virtual ~wxStreamBuffer();
// deprecated, for compatibility only
wxStreamBase *Stream() { return m_stream; }
+ // 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);
void PutToBuffer(const void *buffer, size_t size);
// flags
bool m_destroybuf, // deallocate buffer?
- m_destroystream, // delete associated stream?
m_fixed,
m_flushable;
+
+private:
+// Cannot use
+// DECLARE_NO_COPY_CLASS(wxStreamBuffer)
+// because copy constructor is explicitly declared above;
+// but no copy assignment operator is defined, so declare
+// it private to prevent the compiler from defining it:
+ wxStreamBuffer& operator=(const wxStreamBuffer&);
};
// ---------------------------------------------------------------------------
-// wxBufferedStreams
+// wxBufferedInputStream
// ---------------------------------------------------------------------------
-class WXDLLEXPORT wxBufferedInputStream : public wxFilterInputStream
+class WXDLLIMPEXP_BASE wxBufferedInputStream : public wxFilterInputStream
{
public:
// if a non NULL buffer is given to the stream, it will be deleted by it
virtual off_t OnSysTell() const;
wxStreamBuffer *m_i_streambuf;
+
+ DECLARE_NO_COPY_CLASS(wxBufferedInputStream)
};
-class WXDLLEXPORT wxBufferedOutputStream : public wxFilterOutputStream
+// ----------------------------------------------------------------------------
+// wxBufferedOutputStream
+// ----------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxBufferedOutputStream : public wxFilterOutputStream
{
public:
// if a non NULL buffer is given to the stream, it will be deleted by it
virtual off_t OnSysTell() const;
wxStreamBuffer *m_o_streambuf;
+
+ DECLARE_NO_COPY_CLASS(wxBufferedOutputStream)
};
#endif // wxUSE_STREAMS
projects / wxWidgets.git / blobdiff