X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/af49c4b8a2d3553e733e71c7dd3911881f4c1a2a..85b657c79d32e5876ce5b8ae1e7b9519fee18247:/include/wx/stream.h diff --git a/include/wx/stream.h b/include/wx/stream.h index 488d1905dc..264db502b0 100644 --- a/include/wx/stream.h +++ b/include/wx/stream.h @@ -1,12 +1,12 @@ ///////////////////////////////////////////////////////////////////////////// // 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__ @@ -25,41 +25,49 @@ #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(); @@ -67,80 +75,172 @@ public: // 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(); @@ -166,13 +266,19 @@ protected: 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(); @@ -186,13 +292,15 @@ protected: 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(); @@ -207,9 +315,11 @@ public: protected: wxInputStream *m_parent_i_stream; + + DECLARE_NO_COPY_CLASS(wxFilterInputStream) }; -class WXDLLEXPORT wxFilterOutputStream : public wxOutputStream +class WXDLLIMPEXP_BASE wxFilterOutputStream : public wxOutputStream { public: wxFilterOutputStream(); @@ -222,14 +332,20 @@ public: 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 @@ -240,7 +356,6 @@ public: }; wxStreamBuffer(wxStreamBase& stream, BufMode mode); - wxStreamBuffer(BufMode mode); wxStreamBuffer(const wxStreamBuffer& buf); virtual ~wxStreamBuffer(); @@ -294,6 +409,10 @@ public: // 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); @@ -328,16 +447,23 @@ protected: // 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 @@ -365,9 +491,15 @@ protected: 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 @@ -398,6 +530,8 @@ protected: virtual off_t OnSysTell() const; wxStreamBuffer *m_o_streambuf; + + DECLARE_NO_COPY_CLASS(wxBufferedOutputStream) }; #endif // wxUSE_STREAMS