src/common/stream.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        stream.cpp
   3 // Purpose:     wxStream base classes
   4 // Author:      Guilhem Lavaux
   5 // Modified by:
   6 // Created:     11/07/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Guilhem Lavaux
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "stream.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18 #include <ctype.h>
  19 #include <wx/stream.h>
  20 #include <wx/datstrm.h>
  21 #include <wx/objstrm.h>
  22
  23 #ifdef __BORLANDC__
  24 #pragma hdrstop
  25 #endif
  26
  27 // ----------------------------------------------------------------------------
  28 // wxStreamBuffer
  29 // ----------------------------------------------------------------------------
  30
  31 wxStreamBuffer::wxStreamBuffer(wxInputStream& i_stream)
  32   : m_buffer_start(NULL), m_buffer_end(NULL), m_buffer_pos(NULL),
  33     m_buffer_size(0), m_istream(&i_stream), m_ostream(NULL)
  34 {
  35 }
  36
  37 wxStreamBuffer::wxStreamBuffer(wxOutputStream& o_stream)
  38   : m_buffer_start(NULL), m_buffer_end(NULL), m_buffer_pos(NULL),
  39     m_buffer_size(0), m_istream(NULL), m_ostream(&o_stream)
  40 {
  41 }
  42
  43 wxStreamBuffer::~wxStreamBuffer()
  44 {
  45   wxDELETEA(m_buffer_start);
  46 }
  47
  48 void wxStreamBuffer::WriteBack(char c)
  49 {
  50   if (m_ostream)
  51     return;
  52
  53   // Assume that if we write "back" we have read a few bytes: so we have some
  54   // space.
  55   if (m_buffer_pos == m_buffer_start)
  56     return;
  57
  58   m_buffer_pos--;
  59   *m_buffer_pos = c;
  60 }
  61
  62 void wxStreamBuffer::SetBufferIO(char *buffer_start, char *buffer_end)
  63 {
  64   size_t ret;
  65
  66   m_buffer_start = buffer_start;
  67   m_buffer_end   = buffer_end;
  68
  69   m_buffer_size = m_buffer_end-m_buffer_start;
  70
  71   if (m_istream) {
  72     ret = m_istream->DoRead(m_buffer_start, m_buffer_size);
  73     m_buffer_end = m_buffer_start + ret;
  74   }
  75   m_buffer_pos = m_buffer_start;
  76 }
  77
  78 void wxStreamBuffer::SetBufferIO(size_t bufsize)
  79 {
  80   char *b_start;
  81
  82   wxDELETE(m_buffer_start);
  83
  84   if (!bufsize) {
  85     m_buffer_start = NULL;
  86     m_buffer_end = NULL;
  87     m_buffer_pos = NULL;
  88     m_buffer_size = 0;
  89     return;
  90   }
  91
  92   b_start = new char[bufsize];
  93
  94   SetBufferIO(b_start, b_start + bufsize);
  95 }
  96
  97 void wxStreamBuffer::ResetBuffer()
  98 {
  99   if (m_istream)
 100     m_buffer_pos = m_buffer_end;
 101   else
 102     m_buffer_pos = m_buffer_start;
 103 }
 104
 105 void wxStreamBuffer::Read(void *buffer, size_t size)
 106 {
 107   wxASSERT(m_istream != NULL);
 108
 109   // ------------------
 110   // Buffering disabled
 111   // ------------------
 112
 113   if (!m_buffer_size) {
 114     m_istream->m_lastread = m_istream->DoRead(buffer, size);
 115     return;
 116   }
 117
 118   // -----------------
 119   // Buffering enabled
 120   // -----------------
 121   size_t buf_left, orig_size = size;
 122   size_t read_ret;
 123
 124   while (size > 0) {
 125     buf_left = m_buffer_end - m_buffer_pos;
 126
 127     // First case: the requested buffer is larger than the stream buffer,
 128     //             we split
 129     if (size > buf_left) {
 130       memcpy(buffer, m_buffer_pos, buf_left);
 131       size -= buf_left;
 132       buffer = (char *)buffer + buf_left; // ANSI C++ violation.
 133
 134       read_ret = m_istream->DoRead(m_buffer_start, m_buffer_size);
 135
 136       // Read failed: EOF
 137       if (read_ret == 0) {
 138         m_istream->m_lastread = orig_size-size;
 139         m_istream->m_eof = TRUE;
 140         m_buffer_pos = m_buffer_end = m_buffer_start;
 141         return;
 142       } else {
 143         m_buffer_end = m_buffer_start+read_ret;
 144         m_buffer_pos = m_buffer_start;
 145       }
 146     } else {
 147
 148       // Second case: we just copy from the stream buffer.
 149       memcpy(buffer, m_buffer_pos, size);
 150       m_buffer_pos += size;
 151       break;
 152     }
 153   }
 154   m_istream->m_lastread = orig_size;
 155 }
 156
 157 void wxStreamBuffer::Write(const void *buffer, size_t size)
 158 {
 159   wxASSERT(m_ostream != NULL);
 160
 161   // ------------------
 162   // Buffering disabled
 163   // ------------------
 164
 165   if (!m_buffer_size) {
 166     m_ostream->m_lastwrite = m_ostream->DoWrite(buffer, size);
 167     return;
 168   }
 169
 170   // ------------------
 171   // Buffering enabled
 172   // ------------------
 173
 174   size_t buf_left, orig_size = size;
 175   size_t write_ret;
 176
 177   while (size > 0) {
 178     buf_left = m_buffer_end - m_buffer_pos;
 179
 180     // First case: the buffer to write is larger than the stream buffer,
 181     //             we split it
 182     if (size > buf_left) {
 183       memcpy(m_buffer_pos, buffer, buf_left);
 184       size -= buf_left;
 185       buffer = (char *)buffer + buf_left; // ANSI C++ violation.
 186
 187       write_ret = m_ostream->DoWrite(m_buffer_start, m_buffer_size);
 188       if (write_ret != m_buffer_size) {
 189         m_ostream->m_bad = TRUE;
 190         m_ostream->m_lastwrite = orig_size-size;
 191         m_buffer_pos = m_buffer_end = m_buffer_start;
 192         return;
 193       }
 194       m_buffer_pos = m_buffer_start;
 195
 196     } else {
 197
 198       // Second case: just copy it in the stream buffer.
 199
 200       memcpy(m_buffer_pos, buffer, size);
 201       m_buffer_pos += size;
 202       break;
 203     }
 204   }
 205   m_ostream->m_lastwrite = orig_size;
 206 }
 207
 208 // ----------------------------------------------------------------------------
 209 // wxInputStream
 210 // ----------------------------------------------------------------------------
 211
 212 wxInputStream::wxInputStream()
 213 {
 214   m_i_destroybuf = TRUE;
 215   m_i_streambuf = new wxStreamBuffer(*this);
 216   m_eof = FALSE;
 217   m_lastread = 0;
 218 }
 219
 220 wxInputStream::wxInputStream(wxStreamBuffer *buffer)
 221 {
 222   m_i_destroybuf = FALSE;
 223   m_i_streambuf = buffer;
 224   m_eof = FALSE;
 225   m_lastread = 0;
 226 }
 227
 228 wxInputStream::~wxInputStream()
 229 {
 230   if (m_i_destroybuf)
 231     delete m_i_streambuf;
 232 }
 233
 234 char wxInputStream::GetC()
 235 {
 236   char c;
 237   m_i_streambuf->Read(&c, 1);
 238   return c;
 239 }
 240
 241 wxInputStream& wxInputStream::Read(void *buffer, size_t size)
 242 {
 243   m_i_streambuf->Read(buffer, size);
 244   // wxStreamBuffer sets all variables for us
 245   return *this;
 246 }
 247
 248 #define BUF_TEMP_SIZE 10000
 249
 250 wxInputStream& wxInputStream::Read(wxOutputStream& stream_out)
 251 {
 252   char buf[BUF_TEMP_SIZE];
 253   size_t bytes_read = BUF_TEMP_SIZE;
 254
 255   while (bytes_read == BUF_TEMP_SIZE && !stream_out.Bad()) {
 256     bytes_read = Read(buf, bytes_read).LastRead();
 257
 258     stream_out.Write(buf, bytes_read);
 259   }
 260   return *this;
 261 }
 262
 263 wxInputStream& wxInputStream::operator>>(wxString& line)
 264 {
 265   wxDataInputStream s(*this);
 266
 267   line = s.ReadLine();
 268   return *this;
 269 }
 270
 271 wxInputStream& wxInputStream::operator>>(char& c)
 272 {
 273   c = GetC();
 274   return *this;
 275 }
 276
 277 wxInputStream& wxInputStream::operator>>(short& i)
 278 {
 279   long l;
 280
 281   *this >> l;
 282   i = (short)l;
 283   return *this;
 284 }
 285
 286 wxInputStream& wxInputStream::operator>>(int& i)
 287 {
 288   long l;
 289
 290   *this >> l;
 291   i = (short)l;
 292   return *this;
 293 }
 294
 295 wxInputStream& wxInputStream::operator>>(long& i)
 296 {
 297   /* I only implemented a simple integer parser */
 298   int c, sign;
 299
 300   while (isspace( c = GetC() ) )
 301      /* Do nothing */ ;
 302
 303   i = 0;
 304   if (! (c == '-' || isdigit(c)) ) {
 305     InputStreamBuffer()->WriteBack(c);
 306     return *this;
 307   }
 308
 309   if (c == '-') {
 310     sign = -1;
 311     c = GetC();
 312   } else
 313     sign = 1;
 314
 315   while (isdigit(c)) {
 316     i = i*10 + c;
 317     c = GetC();
 318   }
 319
 320   i *= sign;
 321
 322   return *this;
 323 }
 324
 325 wxInputStream& wxInputStream::operator>>(float& f)
 326 {
 327   /* I only implemented a simple float parser */
 328   int c, sign;
 329
 330   while (isspace( c = GetC() ) )
 331      /* Do nothing */ ;
 332
 333   f = 0.0;
 334   if (! (c == '-' || isdigit(c)) ) {
 335     InputStreamBuffer()->WriteBack(c);
 336     return *this;
 337   }
 338
 339   if (c == '-') {
 340     sign = -1;
 341     c = GetC();
 342   } else
 343     sign = 1;
 344
 345   while (isdigit(c)) {
 346     f = f*10 + c;
 347     c = GetC();
 348   }
 349
 350   if (c == '.') {
 351     float f_multiplicator = (float) 0.1;
 352     c = GetC();
 353
 354     while (isdigit(c)) {
 355       f += c*f_multiplicator;
 356       f_multiplicator /= 10;
 357       c = GetC();
 358     }
 359   }
 360
 361   f *= sign;
 362
 363   return *this;
 364 }
 365
 366 #if USE_SERIAL
 367 wxInputStream& wxInputStream::operator>>(wxObject *& obj)
 368 {
 369   wxObjectInputStream obj_s(*this);
 370   obj = obj_s.LoadObject();
 371   return *this;
 372 }
 373 #endif
 374
 375 off_t wxInputStream::SeekI(off_t pos, wxSeekMode mode)
 376 {
 377   off_t ret_off, diff, last_access;
 378
 379   last_access = m_i_streambuf->GetLastAccess();
 380
 381   switch (mode) {
 382   case wxFromStart:
 383     diff = DoTellInput() - pos;
 384     if ( diff < 0 || diff > last_access  ) {
 385       ret_off = DoSeekInput(pos, wxFromStart);
 386       m_i_streambuf->ResetBuffer();
 387       return ret_off;
 388     } else {
 389       m_i_streambuf->SetIntPosition(last_access - diff);
 390       return pos;
 391     }
 392   case wxFromCurrent:
 393     diff = pos + m_i_streambuf->GetIntPosition();
 394
 395     if ( (diff > last_access) || (diff < 0) ) {
 396       ret_off = DoSeekInput(pos, wxFromCurrent);
 397       m_i_streambuf->ResetBuffer();
 398       return ret_off;
 399     } else {
 400       m_i_streambuf->SetIntPosition(diff);
 401       return pos;
 402     }
 403   case wxFromEnd:
 404     // Hard to compute: always seek to the requested position.
 405     ret_off = DoSeekInput(pos, wxFromEnd);
 406     m_i_streambuf->ResetBuffer();
 407     return ret_off;
 408   }
 409   return wxInvalidOffset;
 410 }
 411
 412 off_t wxInputStream::TellI() const
 413 {
 414   return DoTellInput() - m_i_streambuf->GetLastAccess() +
 415                          m_i_streambuf->GetIntPosition();
 416 }
 417
 418 // ----------------------------------------------------------------------------
 419 // wxOutputStream
 420 // ----------------------------------------------------------------------------
 421 wxOutputStream::wxOutputStream()
 422 {
 423   m_o_destroybuf = TRUE;
 424   m_o_streambuf = new wxStreamBuffer(*this);
 425   m_bad = FALSE;
 426   m_lastwrite = 0;
 427 }
 428
 429 wxOutputStream::wxOutputStream(wxStreamBuffer *buffer)
 430 {
 431   m_o_destroybuf = FALSE;
 432   m_o_streambuf = buffer;
 433   m_bad = FALSE;
 434   m_lastwrite = 0;
 435 }
 436
 437 wxOutputStream::~wxOutputStream()
 438 {
 439   if (m_o_destroybuf)
 440     delete m_o_streambuf;
 441 }
 442
 443 wxOutputStream& wxOutputStream::Write(const void *buffer, size_t size)
 444 {
 445   m_o_streambuf->Write(buffer, size);
 446   return *this;
 447 }
 448
 449 wxOutputStream& wxOutputStream::Write(wxInputStream& stream_in)
 450 {
 451   stream_in.Read(*this);
 452   return *this;
 453 }
 454
 455 off_t wxOutputStream::SeekO(off_t pos, wxSeekMode mode)
 456 {
 457   off_t ret_off;
 458
 459   switch (mode) {
 460   case wxFromStart:
 461     if ( (unsigned)abs (DoTellOutput()-pos) > m_o_streambuf->GetLastAccess()  ) {
 462       ret_off = DoSeekOutput(pos, wxFromStart);
 463       m_o_streambuf->ResetBuffer();
 464       return ret_off;
 465     } else {
 466       m_o_streambuf->SetIntPosition( DoTellOutput() - pos);
 467       return pos;
 468     }
 469   case wxFromCurrent:
 470     if ( ((unsigned)pos > m_o_streambuf->GetLastAccess()) || (pos < 0) ) {
 471       ret_off = DoSeekOutput(pos, wxFromCurrent);
 472       m_o_streambuf->ResetBuffer();
 473       return ret_off;
 474     } else {
 475       m_o_streambuf->SetIntPosition(pos);
 476       return pos;
 477     }
 478   case wxFromEnd:
 479     // Hard to compute: always seek to the requested position.
 480     ret_off = DoSeekOutput(pos, wxFromEnd);
 481     m_o_streambuf->ResetBuffer();
 482     return ret_off;
 483   }
 484   return wxInvalidOffset;
 485 }
 486
 487 off_t wxOutputStream::TellO() const
 488 {
 489   return DoTellOutput() - m_o_streambuf->GetLastAccess()
 490                         + m_o_streambuf->GetIntPosition();
 491 }
 492
 493 void wxOutputStream::Sync()
 494 {
 495   DoWrite(m_o_streambuf->GetBufferStart(), m_o_streambuf->GetIntPosition());
 496
 497   m_o_streambuf->ResetBuffer();
 498 }
 499
 500 wxOutputStream& wxOutputStream::operator<<(const char *string)
 501 {
 502   return Write(string, strlen(string));
 503 }
 504
 505 wxOutputStream& wxOutputStream::operator<<(wxString& string)
 506 {
 507   return Write(string, string.Len());
 508 }
 509
 510 wxOutputStream& wxOutputStream::operator<<(char c)
 511 {
 512   return Write(&c, 1);
 513 }
 514
 515 wxOutputStream& wxOutputStream::operator<<(short i)
 516 {
 517   wxString strint;
 518
 519   strint.Printf("%i", i);
 520   return Write(strint, strint.Len());
 521 }
 522
 523 wxOutputStream& wxOutputStream::operator<<(int i)
 524 {
 525   wxString strint;
 526
 527   strint.Printf("%i", i);
 528   return Write(strint, strint.Len());
 529 }
 530
 531 wxOutputStream& wxOutputStream::operator<<(long i)
 532 {
 533   wxString strlong;
 534
 535   strlong.Printf("%i", i);
 536   return Write((const char *)strlong, strlong.Len());
 537 }
 538
 539 wxOutputStream& wxOutputStream::operator<<(double f)
 540 {
 541   wxString strfloat;
 542
 543   strfloat.Printf("%f", f);
 544   return Write(strfloat, strfloat.Len());
 545 }
 546
 547 #if USE_SERIAL
 548 wxOutputStream& wxOutputStream::operator<<(wxObject& obj)
 549 {
 550   wxObjectOutputStream obj_s(*this);
 551   obj_s.SaveObject(obj);
 552   return *this;
 553 }
 554 #endif
 555
 556 // ----------------------------------------------------------------------------
 557 // wxStream
 558 // ----------------------------------------------------------------------------
 559
 560 wxStream::wxStream()
 561   : wxInputStream(), wxOutputStream()
 562 {
 563 }
 564
 565 // ----------------------------------------------------------------------------
 566 // wxFilterInputStream
 567 // ----------------------------------------------------------------------------
 568 wxFilterInputStream::wxFilterInputStream()
 569   : wxInputStream(NULL)
 570 {
 571 }
 572
 573 wxFilterInputStream::wxFilterInputStream(wxInputStream& stream)
 574   : wxInputStream(NULL)
 575 {
 576   m_parent_i_stream = &stream;
 577   wxDELETE(m_i_streambuf); // In case m_i_streambuf has been initialized.
 578   m_i_destroybuf = FALSE;
 579   m_i_streambuf = stream.InputStreamBuffer();
 580 }
 581
 582 wxFilterInputStream::~wxFilterInputStream()
 583 {
 584 }
 585
 586 size_t wxFilterInputStream::DoRead(void *buffer, size_t size)
 587 {
 588   return m_parent_i_stream->Read(buffer, size).LastRead();
 589 }
 590
 591 off_t wxFilterInputStream::DoSeekInput(off_t pos, wxSeekMode mode)
 592 {
 593   return m_parent_i_stream->SeekI(pos, mode);
 594 }
 595
 596 off_t wxFilterInputStream::DoTellInput() const
 597 {
 598   return m_parent_i_stream->TellI();
 599 }
 600
 601 // ----------------------------------------------------------------------------
 602 // wxFilterOutputStream
 603 // ----------------------------------------------------------------------------
 604 wxFilterOutputStream::wxFilterOutputStream()
 605   : wxOutputStream(NULL)
 606 {
 607 }
 608
 609 wxFilterOutputStream::wxFilterOutputStream(wxOutputStream& stream)
 610   : wxOutputStream(NULL)
 611 {
 612   m_parent_o_stream = &stream;
 613   wxDELETE(m_o_streambuf); // In case m_o_streambuf has been initialized.
 614   m_o_destroybuf = FALSE;
 615   m_o_streambuf = stream.OutputStreamBuffer();
 616 }
 617
 618 wxFilterOutputStream::~wxFilterOutputStream()
 619 {
 620 }
 621
 622 size_t wxFilterOutputStream::DoWrite(const void *buffer, size_t size)
 623 {
 624   return m_parent_o_stream->Write(buffer, size).LastWrite();
 625 }
 626
 627 off_t wxFilterOutputStream::DoSeekOutput(off_t pos, wxSeekMode mode)
 628 {
 629   return m_parent_o_stream->SeekO(pos, mode);
 630 }
 631
 632 off_t wxFilterOutputStream::DoTellOutput() const
 633 {
 634   return m_parent_o_stream->TellO();
 635 }
 636
 637 // ----------------------------------------------------------------------------
 638 // wxFilterStream
 639 // ----------------------------------------------------------------------------
 640
 641 wxFilterStream::wxFilterStream()
 642 {
 643 }
 644
 645 wxFilterStream::wxFilterStream(wxStream& stream)
 646   : wxFilterInputStream(stream), wxFilterOutputStream(stream)
 647 {
 648 }
 649
 650 // ----------------------------------------------------------------------------
 651 // Some IOManip function
 652 // ----------------------------------------------------------------------------
 653
 654 wxOutputStream& wxEndL(wxOutputStream& stream)
 655 {
 656 #ifdef __MSW__
 657   return stream.Write("\r\n", 2);
 658 #else
 659   return stream.Write("\n", 1);
 660 #endif
 661 }