include/wx/stream.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/stream.h
   3 // Purpose:     stream classes
   4 // Author:      Guilhem Lavaux, Guillermo Rodriguez Garcia, Vadim Zeitlin
   5 // Modified by:
   6 // Created:     11/07/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Guilhem Lavaux
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_WXSTREAM_H__
  13 #define _WX_WXSTREAM_H__
  14
  15 #include "wx/defs.h"
  16
  17 #if wxUSE_STREAMS
  18
  19 #include <stdio.h>
  20 #include "wx/object.h"
  21 #include "wx/string.h"
  22 #include "wx/filefn.h"  // for wxFileOffset, wxInvalidOffset and wxSeekMode
  23
  24 class WXDLLIMPEXP_FWD_BASE wxStreamBase;
  25 class WXDLLIMPEXP_FWD_BASE wxInputStream;
  26 class WXDLLIMPEXP_FWD_BASE wxOutputStream;
  27
  28 typedef wxInputStream& (*__wxInputManip)(wxInputStream&);
  29 typedef wxOutputStream& (*__wxOutputManip)(wxOutputStream&);
  30
  31 WXDLLIMPEXP_BASE wxOutputStream& wxEndL(wxOutputStream& o_stream);
  32
  33 // ----------------------------------------------------------------------------
  34 // constants
  35 // ----------------------------------------------------------------------------
  36
  37 enum wxStreamError
  38 {
  39     wxSTREAM_NO_ERROR = 0,      // stream is in good state
  40     wxSTREAM_EOF,               // EOF reached in Read() or similar
  41     wxSTREAM_WRITE_ERROR,       // generic write error
  42     wxSTREAM_READ_ERROR         // generic read error
  43 };
  44
  45 const int wxEOF = -1;
  46
  47 // ============================================================================
  48 // base stream classes: wxInputStream and wxOutputStream
  49 // ============================================================================
  50
  51 // ---------------------------------------------------------------------------
  52 // wxStreamBase: common (but non virtual!) base for all stream classes
  53 // ---------------------------------------------------------------------------
  54
  55 class WXDLLIMPEXP_BASE wxStreamBase : public wxObject
  56 {
  57 public:
  58     wxStreamBase();
  59     virtual ~wxStreamBase();
  60
  61     // error testing
  62     wxStreamError GetLastError() const { return m_lasterror; }
  63     virtual bool IsOk() const { return GetLastError() == wxSTREAM_NO_ERROR; }
  64     bool operator!() const { return !IsOk(); }
  65
  66     // reset the stream state
  67     void Reset(wxStreamError error = wxSTREAM_NO_ERROR) { m_lasterror = error; }
  68
  69     // this doesn't make sense for all streams, always test its return value
  70     virtual size_t GetSize() const;
  71     virtual wxFileOffset GetLength() const { return wxInvalidOffset; }
  72
  73     // returns true if the streams supports seeking to arbitrary offsets
  74     virtual bool IsSeekable() const { return false; }
  75
  76 protected:
  77     virtual wxFileOffset OnSysSeek(wxFileOffset seek, wxSeekMode mode);
  78     virtual wxFileOffset OnSysTell() const;
  79
  80     size_t m_lastcount;
  81     wxStreamError m_lasterror;
  82
  83     friend class wxStreamBuffer;
  84
  85     DECLARE_ABSTRACT_CLASS(wxStreamBase)
  86     wxDECLARE_NO_COPY_CLASS(wxStreamBase);
  87 };
  88
  89 // ----------------------------------------------------------------------------
  90 // wxInputStream: base class for the input streams
  91 // ----------------------------------------------------------------------------
  92
  93 class WXDLLIMPEXP_BASE wxInputStream : public wxStreamBase
  94 {
  95 public:
  96     // ctor and dtor, nothing exciting
  97     wxInputStream();
  98     virtual ~wxInputStream();
  99
 100
 101     // IO functions
 102     // ------------
 103
 104     // return a character from the stream without removing it, i.e. it will
 105     // still be returned by the next call to GetC()
 106     //
 107     // blocks until something appears in the stream if necessary, if nothing
 108     // ever does (i.e. EOF) LastRead() will return 0 (and the return value is
 109     // undefined), otherwise 1
 110     virtual char Peek();
 111
 112     // return one byte from the stream, blocking until it appears if
 113     // necessary
 114     //
 115     // on success returns a value between 0 - 255, or wxEOF on EOF or error.
 116     int GetC();
 117
 118     // read at most the given number of bytes from the stream
 119     //
 120     // there are 2 possible situations here: either there is nothing at all in
 121     // the stream right now in which case Read() blocks until something appears
 122     // (use CanRead() to avoid this) or there is already some data available in
 123     // the stream and then Read() doesn't block but returns just the data it
 124     // can read without waiting for more
 125     //
 126     // in any case, if there are not enough bytes in the stream right now,
 127     // LastRead() value will be less than size but greater than 0. If it is 0,
 128     // it means that EOF has been reached.
 129     virtual wxInputStream& Read(void *buffer, size_t size);
 130
 131     // Read exactly the given number of bytes, unlike Read(), which may read
 132     // less than the requested amount of data without returning an error, this
 133     // method either reads all the data or returns false.
 134     bool ReadAll(void *buffer, size_t size);
 135
 136     // copy the entire contents of this stream into streamOut, stopping only
 137     // when EOF is reached or an error occurs
 138     wxInputStream& Read(wxOutputStream& streamOut);
 139
 140
 141     // status functions
 142     // ----------------
 143
 144     // returns the number of bytes read by the last call to Read(), GetC() or
 145     // Peek()
 146     //
 147     // this should be used to discover whether that call succeeded in reading
 148     // all the requested data or not
 149     virtual size_t LastRead() const { return wxStreamBase::m_lastcount; }
 150
 151     // returns true if some data is available in the stream right now, so that
 152     // calling Read() wouldn't block
 153     virtual bool CanRead() const;
 154
 155     // is the stream at EOF?
 156     //
 157     // note that this cannot be really implemented for all streams and
 158     // CanRead() is more reliable than Eof()
 159     virtual bool Eof() const;
 160
 161
 162     // write back buffer
 163     // -----------------
 164
 165     // put back the specified number of bytes into the stream, they will be
 166     // fetched by the next call to the read functions
 167     //
 168     // returns the number of bytes really stuffed back
 169     size_t Ungetch(const void *buffer, size_t size);
 170
 171     // put back the specified character in the stream
 172     //
 173     // returns true if ok, false on error
 174     bool Ungetch(char c);
 175
 176
 177     // position functions
 178     // ------------------
 179
 180     // move the stream pointer to the given position (if the stream supports
 181     // it)
 182     //
 183     // returns wxInvalidOffset on error
 184     virtual wxFileOffset SeekI(wxFileOffset pos, wxSeekMode mode = wxFromStart);
 185
 186     // return the current position of the stream pointer or wxInvalidOffset
 187     virtual wxFileOffset TellI() const;
 188
 189
 190     // stream-like operators
 191     // ---------------------
 192
 193     wxInputStream& operator>>(wxOutputStream& out) { return Read(out); }
 194     wxInputStream& operator>>(__wxInputManip func) { return func(*this); }
 195
 196 protected:
 197     // do read up to size bytes of data into the provided buffer
 198     //
 199     // this method should return 0 if EOF has been reached or an error occurred
 200     // (m_lasterror should be set accordingly as well) or the number of bytes
 201     // read
 202     virtual size_t OnSysRead(void *buffer, size_t size) = 0;
 203
 204     // write-back buffer support
 205     // -------------------------
 206
 207     // return the pointer to a buffer big enough to hold sizeNeeded bytes
 208     char *AllocSpaceWBack(size_t sizeNeeded);
 209
 210     // read up to size data from the write back buffer, return the number of
 211     // bytes read
 212     size_t GetWBack(void *buf, size_t size);
 213
 214     // write back buffer or NULL if none
 215     char *m_wback;
 216
 217     // the size of the buffer
 218     size_t m_wbacksize;
 219
 220     // the current position in the buffer
 221     size_t m_wbackcur;
 222
 223     friend class wxStreamBuffer;
 224
 225     DECLARE_ABSTRACT_CLASS(wxInputStream)
 226     wxDECLARE_NO_COPY_CLASS(wxInputStream);
 227 };
 228
 229 // ----------------------------------------------------------------------------
 230 // wxOutputStream: base for the output streams
 231 // ----------------------------------------------------------------------------
 232
 233 class WXDLLIMPEXP_BASE wxOutputStream : public wxStreamBase
 234 {
 235 public:
 236     wxOutputStream();
 237     virtual ~wxOutputStream();
 238
 239     void PutC(char c);
 240     virtual wxOutputStream& Write(const void *buffer, size_t size);
 241
 242     // This is ReadAll() equivalent for Write(): it either writes exactly the
 243     // given number of bytes or returns false, unlike Write() which can write
 244     // less data than requested but still return without error.
 245     bool WriteAll(const void *buffer, size_t size);
 246
 247     wxOutputStream& Write(wxInputStream& stream_in);
 248
 249     virtual wxFileOffset SeekO(wxFileOffset pos, wxSeekMode mode = wxFromStart);
 250     virtual wxFileOffset TellO() const;
 251
 252     virtual size_t LastWrite() const { return wxStreamBase::m_lastcount; }
 253
 254     virtual void Sync();
 255     virtual bool Close() { return true; }
 256
 257     wxOutputStream& operator<<(wxInputStream& out) { return Write(out); }
 258     wxOutputStream& operator<<( __wxOutputManip func) { return func(*this); }
 259
 260 protected:
 261     // to be implemented in the derived classes (it should have been pure
 262     // virtual)
 263     virtual size_t OnSysWrite(const void *buffer, size_t bufsize);
 264
 265     friend class wxStreamBuffer;
 266
 267     DECLARE_ABSTRACT_CLASS(wxOutputStream)
 268     wxDECLARE_NO_COPY_CLASS(wxOutputStream);
 269 };
 270
 271 // ============================================================================
 272 // helper stream classes
 273 // ============================================================================
 274
 275 // ---------------------------------------------------------------------------
 276 // A stream for measuring streamed output
 277 // ---------------------------------------------------------------------------
 278
 279 class WXDLLIMPEXP_BASE wxCountingOutputStream : public wxOutputStream
 280 {
 281 public:
 282     wxCountingOutputStream();
 283
 284     wxFileOffset GetLength() const;
 285     bool Ok() const { return IsOk(); }
 286     bool IsOk() const { return true; }
 287
 288 protected:
 289     virtual size_t OnSysWrite(const void *buffer, size_t size);
 290     virtual wxFileOffset OnSysSeek(wxFileOffset pos, wxSeekMode mode);
 291     virtual wxFileOffset OnSysTell() const;
 292
 293     size_t m_currentPos;
 294
 295     DECLARE_DYNAMIC_CLASS(wxCountingOutputStream)
 296     wxDECLARE_NO_COPY_CLASS(wxCountingOutputStream);
 297 };
 298
 299 // ---------------------------------------------------------------------------
 300 // "Filter" streams
 301 // ---------------------------------------------------------------------------
 302
 303 class WXDLLIMPEXP_BASE wxFilterInputStream : public wxInputStream
 304 {
 305 public:
 306     wxFilterInputStream();
 307     wxFilterInputStream(wxInputStream& stream);
 308     wxFilterInputStream(wxInputStream *stream);
 309     virtual ~wxFilterInputStream();
 310
 311     char Peek() { return m_parent_i_stream->Peek(); }
 312
 313     wxFileOffset GetLength() const { return m_parent_i_stream->GetLength(); }
 314
 315     wxInputStream *GetFilterInputStream() const { return m_parent_i_stream; }
 316
 317 protected:
 318     wxInputStream *m_parent_i_stream;
 319     bool m_owns;
 320
 321     DECLARE_ABSTRACT_CLASS(wxFilterInputStream)
 322     wxDECLARE_NO_COPY_CLASS(wxFilterInputStream);
 323 };
 324
 325 class WXDLLIMPEXP_BASE wxFilterOutputStream : public wxOutputStream
 326 {
 327 public:
 328     wxFilterOutputStream();
 329     wxFilterOutputStream(wxOutputStream& stream);
 330     wxFilterOutputStream(wxOutputStream *stream);
 331     virtual ~wxFilterOutputStream();
 332
 333     wxFileOffset GetLength() const { return m_parent_o_stream->GetLength(); }
 334
 335     wxOutputStream *GetFilterOutputStream() const { return m_parent_o_stream; }
 336
 337     bool Close();
 338
 339 protected:
 340     wxOutputStream *m_parent_o_stream;
 341     bool m_owns;
 342
 343     DECLARE_ABSTRACT_CLASS(wxFilterOutputStream)
 344     wxDECLARE_NO_COPY_CLASS(wxFilterOutputStream);
 345 };
 346
 347 enum wxStreamProtocolType
 348 {
 349     wxSTREAM_PROTOCOL,  // wxFileSystem protocol (should be only one)
 350     wxSTREAM_MIMETYPE,  // MIME types the stream handles
 351     wxSTREAM_ENCODING,  // The HTTP Content-Encodings the stream handles
 352     wxSTREAM_FILEEXT    // File extensions the stream handles
 353 };
 354
 355 void WXDLLIMPEXP_BASE wxUseFilterClasses();
 356
 357 class WXDLLIMPEXP_BASE wxFilterClassFactoryBase : public wxObject
 358 {
 359 public:
 360     virtual ~wxFilterClassFactoryBase() { }
 361
 362     wxString GetProtocol() const { return wxString(*GetProtocols()); }
 363     wxString PopExtension(const wxString& location) const;
 364
 365     virtual const wxChar * const *GetProtocols(wxStreamProtocolType type
 366                                                = wxSTREAM_PROTOCOL) const = 0;
 367
 368     bool CanHandle(const wxString& protocol,
 369                    wxStreamProtocolType type
 370                    = wxSTREAM_PROTOCOL) const;
 371
 372 protected:
 373     wxString::size_type FindExtension(const wxString& location) const;
 374
 375     DECLARE_ABSTRACT_CLASS(wxFilterClassFactoryBase)
 376 };
 377
 378 class WXDLLIMPEXP_BASE wxFilterClassFactory : public wxFilterClassFactoryBase
 379 {
 380 public:
 381     virtual ~wxFilterClassFactory() { }
 382
 383     virtual wxFilterInputStream  *NewStream(wxInputStream& stream)  const = 0;
 384     virtual wxFilterOutputStream *NewStream(wxOutputStream& stream) const = 0;
 385     virtual wxFilterInputStream  *NewStream(wxInputStream *stream)  const = 0;
 386     virtual wxFilterOutputStream *NewStream(wxOutputStream *stream) const = 0;
 387
 388     static const wxFilterClassFactory *Find(const wxString& protocol,
 389                                             wxStreamProtocolType type
 390                                             = wxSTREAM_PROTOCOL);
 391
 392     static const wxFilterClassFactory *GetFirst();
 393     const wxFilterClassFactory *GetNext() const { return m_next; }
 394
 395     void PushFront() { Remove(); m_next = sm_first; sm_first = this; }
 396     void Remove();
 397
 398 protected:
 399     wxFilterClassFactory() : m_next(this) { }
 400
 401     wxFilterClassFactory& operator=(const wxFilterClassFactory&)
 402         { return *this; }
 403
 404 private:
 405     static wxFilterClassFactory *sm_first;
 406     wxFilterClassFactory *m_next;
 407
 408     DECLARE_ABSTRACT_CLASS(wxFilterClassFactory)
 409 };
 410
 411 // ============================================================================
 412 // buffered streams
 413 // ============================================================================
 414
 415 // ---------------------------------------------------------------------------
 416 // Stream buffer: this class can be derived from and passed to
 417 // wxBufferedStreams to implement custom buffering
 418 // ---------------------------------------------------------------------------
 419
 420 class WXDLLIMPEXP_BASE wxStreamBuffer
 421 {
 422 public:
 423     enum BufMode
 424     {
 425         read,
 426         write,
 427         read_write
 428     };
 429
 430     wxStreamBuffer(wxStreamBase& stream, BufMode mode)
 431     {
 432         InitWithStream(stream, mode);
 433     }
 434
 435     wxStreamBuffer(size_t bufsize, wxInputStream& stream)
 436     {
 437         InitWithStream(stream, read);
 438         SetBufferIO(bufsize);
 439     }
 440
 441     wxStreamBuffer(size_t bufsize, wxOutputStream& stream)
 442     {
 443         InitWithStream(stream, write);
 444         SetBufferIO(bufsize);
 445     }
 446
 447     wxStreamBuffer(const wxStreamBuffer& buf);
 448     virtual ~wxStreamBuffer();
 449
 450     // Filtered IO
 451     virtual size_t Read(void *buffer, size_t size);
 452     size_t Read(wxStreamBuffer *buf);
 453     virtual size_t Write(const void *buffer, size_t size);
 454     size_t Write(wxStreamBuffer *buf);
 455
 456     virtual char Peek();
 457     virtual char GetChar();
 458     virtual void PutChar(char c);
 459     virtual wxFileOffset Tell() const;
 460     virtual wxFileOffset Seek(wxFileOffset pos, wxSeekMode mode);
 461
 462     // Buffer control
 463     void ResetBuffer();
 464     void Truncate();
 465
 466     // NB: the buffer must always be allocated with malloc() if takeOwn is
 467     //     true as it will be deallocated by free()
 468     void SetBufferIO(void *start, void *end, bool takeOwnership = false);
 469     void SetBufferIO(void *start, size_t len, bool takeOwnership = false);
 470     void SetBufferIO(size_t bufsize);
 471     void *GetBufferStart() const { return m_buffer_start; }
 472     void *GetBufferEnd() const { return m_buffer_end; }
 473     void *GetBufferPos() const { return m_buffer_pos; }
 474     size_t GetBufferSize() const { return m_buffer_end - m_buffer_start; }
 475     size_t GetIntPosition() const { return m_buffer_pos - m_buffer_start; }
 476     void SetIntPosition(size_t pos) { m_buffer_pos = m_buffer_start + pos; }
 477     size_t GetLastAccess() const { return m_buffer_end - m_buffer_start; }
 478     size_t GetBytesLeft() const { return m_buffer_end - m_buffer_pos; }
 479
 480     void Fixed(bool fixed) { m_fixed = fixed; }
 481     void Flushable(bool f) { m_flushable = f; }
 482
 483     bool FlushBuffer();
 484     bool FillBuffer();
 485     size_t GetDataLeft();
 486
 487     // misc accessors
 488     wxStreamBase *GetStream() const { return m_stream; }
 489     bool HasBuffer() const { return m_buffer_start != m_buffer_end; }
 490
 491     bool IsFixed() const { return m_fixed; }
 492     bool IsFlushable() const { return m_flushable; }
 493
 494     // only for input/output buffers respectively, returns NULL otherwise
 495     wxInputStream *GetInputStream() const;
 496     wxOutputStream *GetOutputStream() const;
 497
 498 #if WXWIN_COMPATIBILITY_2_6
 499     // deprecated, for compatibility only
 500     wxDEPRECATED( wxStreamBase *Stream() );
 501 #endif // WXWIN_COMPATIBILITY_2_6
 502
 503     // this constructs a dummy wxStreamBuffer, used by (and exists for)
 504     // wxMemoryStreams only, don't use!
 505     wxStreamBuffer(BufMode mode);
 506
 507 protected:
 508     void GetFromBuffer(void *buffer, size_t size);
 509     void PutToBuffer(const void *buffer, size_t size);
 510
 511     // set the last error to the specified value if we didn't have it before
 512     void SetError(wxStreamError err);
 513
 514     // common part of several ctors
 515     void Init();
 516
 517     // common part of ctors taking wxStreamBase parameter
 518     void InitWithStream(wxStreamBase& stream, BufMode mode);
 519
 520     // init buffer variables to be empty
 521     void InitBuffer();
 522
 523     // free the buffer (always safe to call)
 524     void FreeBuffer();
 525
 526     // the buffer itself: the pointers to its start and end and the current
 527     // position in the buffer
 528     char *m_buffer_start,
 529          *m_buffer_end,
 530          *m_buffer_pos;
 531
 532     // the stream we're associated with
 533     wxStreamBase *m_stream;
 534
 535     // its mode
 536     BufMode m_mode;
 537
 538     // flags
 539     bool m_destroybuf,      // deallocate buffer?
 540          m_fixed,
 541          m_flushable;
 542
 543
 544     wxDECLARE_NO_ASSIGN_CLASS(wxStreamBuffer);
 545 };
 546
 547 // ---------------------------------------------------------------------------
 548 // wxBufferedInputStream
 549 // ---------------------------------------------------------------------------
 550
 551 class WXDLLIMPEXP_BASE wxBufferedInputStream : public wxFilterInputStream
 552 {
 553 public:
 554     // create a buffered stream on top of the specified low-level stream
 555     //
 556     // if a non NULL buffer is given to the stream, it will be deleted by it,
 557     // otherwise a default 1KB buffer will be used
 558     wxBufferedInputStream(wxInputStream& stream,
 559                           wxStreamBuffer *buffer = NULL);
 560
 561     // ctor allowing to specify the buffer size, it's just a more convenient
 562     // alternative to creating wxStreamBuffer, calling its SetBufferIO(bufsize)
 563     // and using the ctor above
 564     wxBufferedInputStream(wxInputStream& stream, size_t bufsize);
 565
 566
 567     virtual ~wxBufferedInputStream();
 568
 569     char Peek();
 570     wxInputStream& Read(void *buffer, size_t size);
 571
 572     // Position functions
 573     wxFileOffset SeekI(wxFileOffset pos, wxSeekMode mode = wxFromStart);
 574     wxFileOffset TellI() const;
 575     bool IsSeekable() const { return m_parent_i_stream->IsSeekable(); }
 576
 577     // the buffer given to the stream will be deleted by it
 578     void SetInputStreamBuffer(wxStreamBuffer *buffer);
 579     wxStreamBuffer *GetInputStreamBuffer() const { return m_i_streambuf; }
 580
 581 #if WXWIN_COMPATIBILITY_2_6
 582     // deprecated, for compatibility only
 583     wxDEPRECATED( wxStreamBuffer *InputStreamBuffer() const );
 584 #endif // WXWIN_COMPATIBILITY_2_6
 585
 586 protected:
 587     virtual size_t OnSysRead(void *buffer, size_t bufsize);
 588     virtual wxFileOffset OnSysSeek(wxFileOffset seek, wxSeekMode mode);
 589     virtual wxFileOffset OnSysTell() const;
 590
 591     wxStreamBuffer *m_i_streambuf;
 592
 593     wxDECLARE_NO_COPY_CLASS(wxBufferedInputStream);
 594 };
 595
 596 // ----------------------------------------------------------------------------
 597 // wxBufferedOutputStream
 598 // ----------------------------------------------------------------------------
 599
 600 class WXDLLIMPEXP_BASE wxBufferedOutputStream : public wxFilterOutputStream
 601 {
 602 public:
 603     // create a buffered stream on top of the specified low-level stream
 604     //
 605     // if a non NULL buffer is given to the stream, it will be deleted by it,
 606     // otherwise a default 1KB buffer will be used
 607     wxBufferedOutputStream(wxOutputStream& stream,
 608                            wxStreamBuffer *buffer = NULL);
 609
 610     // ctor allowing to specify the buffer size, it's just a more convenient
 611     // alternative to creating wxStreamBuffer, calling its SetBufferIO(bufsize)
 612     // and using the ctor above
 613     wxBufferedOutputStream(wxOutputStream& stream, size_t bufsize);
 614
 615     virtual ~wxBufferedOutputStream();
 616
 617     wxOutputStream& Write(const void *buffer, size_t size);
 618
 619     // Position functions
 620     wxFileOffset SeekO(wxFileOffset pos, wxSeekMode mode = wxFromStart);
 621     wxFileOffset TellO() const;
 622     bool IsSeekable() const { return m_parent_o_stream->IsSeekable(); }
 623
 624     void Sync();
 625     bool Close();
 626
 627     wxFileOffset GetLength() const;
 628
 629     // the buffer given to the stream will be deleted by it
 630     void SetOutputStreamBuffer(wxStreamBuffer *buffer);
 631     wxStreamBuffer *GetOutputStreamBuffer() const { return m_o_streambuf; }
 632
 633 #if WXWIN_COMPATIBILITY_2_6
 634     // deprecated, for compatibility only
 635     wxDEPRECATED( wxStreamBuffer *OutputStreamBuffer() const );
 636 #endif // WXWIN_COMPATIBILITY_2_6
 637
 638 protected:
 639     virtual size_t OnSysWrite(const void *buffer, size_t bufsize);
 640     virtual wxFileOffset OnSysSeek(wxFileOffset seek, wxSeekMode mode);
 641     virtual wxFileOffset OnSysTell() const;
 642
 643     wxStreamBuffer *m_o_streambuf;
 644
 645     wxDECLARE_NO_COPY_CLASS(wxBufferedOutputStream);
 646 };
 647
 648 #if WXWIN_COMPATIBILITY_2_6
 649     inline wxStreamBase *wxStreamBuffer::Stream() { return m_stream; }
 650     inline wxStreamBuffer *wxBufferedInputStream::InputStreamBuffer() const { return m_i_streambuf; }
 651     inline wxStreamBuffer *wxBufferedOutputStream::OutputStreamBuffer() const { return m_o_streambuf; }
 652 #endif // WXWIN_COMPATIBILITY_2_6
 653
 654 // ---------------------------------------------------------------------------
 655 // wxWrapperInputStream: forwards all IO to another stream.
 656 // ---------------------------------------------------------------------------
 657
 658 class WXDLLIMPEXP_BASE wxWrapperInputStream : public wxFilterInputStream
 659 {
 660 public:
 661     // Constructor fully initializing the stream. The overload taking pointer
 662     // takes ownership of the parent stream, the one taking reference does not.
 663     //
 664     // Notice that this class also has a default ctor but it's protected as the
 665     // derived class is supposed to take care of calling InitParentStream() if
 666     // it's used.
 667     wxWrapperInputStream(wxInputStream& stream);
 668     wxWrapperInputStream(wxInputStream* stream);
 669
 670     // Override the base class methods to forward to the wrapped stream.
 671     virtual wxFileOffset GetLength() const;
 672     virtual bool IsSeekable() const;
 673
 674 protected:
 675     virtual size_t OnSysRead(void *buffer, size_t size);
 676     virtual wxFileOffset OnSysSeek(wxFileOffset pos, wxSeekMode mode);
 677     virtual wxFileOffset OnSysTell() const;
 678
 679     // Ensure that our own last error is the same as that of the real stream.
 680     //
 681     // This method is const because the error must be updated even from const
 682     // methods (in other words, it really should have been mutable in the first
 683     // place).
 684     void SynchronizeLastError() const
 685     {
 686         const_cast<wxWrapperInputStream*>(this)->
 687             Reset(m_parent_i_stream->GetLastError());
 688     }
 689
 690     // Default constructor, use InitParentStream() later.
 691     wxWrapperInputStream();
 692
 693     // Set up the wrapped stream for an object initialized using the default
 694     // constructor. The ownership logic is the same as above.
 695     void InitParentStream(wxInputStream& stream);
 696     void InitParentStream(wxInputStream* stream);
 697
 698     wxDECLARE_NO_COPY_CLASS(wxWrapperInputStream);
 699 };
 700
 701
 702 #endif // wxUSE_STREAMS
 703
 704 #endif // _WX_WXSTREAM_H__